JP6529211B2 - Bearing device, manufacturing method of bearing device, and information recording and reproducing apparatus - Google Patents

Description

  The present invention relates to a bearing device, a method of manufacturing the bearing device, and an information recording and reproducing device.

  2. Description of the Related Art Conventionally, there has been known an information recording and reproducing apparatus such as a hard disk which records and reproduces various information on a disk (corresponding to "magnetic recording medium" in the claims). Generally, an information recording / reproducing apparatus includes a head gimbal assembly provided with a slider for recording / reproducing a signal on a disk, and an arm (corresponding to a "pivoting member" in the claims) having a head gimbal assembly mounted on the tip side. Is equipped. The arm is pivotable by a bearing device provided on the proximal side. By rotating the arm, the slider can be moved to a predetermined position on the disc to record and reproduce signals.

  In general, a bearing device includes a shaft and a pair of rolling bearings inserted in the shaft and arranged in the axial direction of the shaft. Further, the pair of rolling bearing portions includes an inner ring fixed to the shaft, an outer ring surrounding the inner ring, and a plurality of rolling elements disposed between the inner ring and the outer ring. Grease is filled in the gap between the inner ring and the outer ring in order to assist the smooth rotation of the rolling bearing portion.

  In the manufacturing process of the above-mentioned bearing device, the operation which arranges a plurality of rolling elements equally between an inner ring and an outer ring is performed (for example, refer to patent documents 1). Generally, in order to arrange a plurality of rolling elements evenly between the inner ring and the outer ring, the central axes of the inner ring and the outer ring are relatively shifted in the radial direction, and the outer diameter of the rolling elements is set between the inner ring and the outer ring A plurality of rolling elements are individually inserted between the inner ring and the outer ring while providing a large clearance. Then, after arranging a plurality of rolling elements equally in the circumferential direction, a retainer that can be held is mounted in a state in which the rolling elements are evenly arranged in a freely rolling manner.

JP, 2008-202606, A

  However, in the conventional bearing device, since the plurality of rolling elements are inserted between the inner ring and the outer ring while shifting the inner ring and the outer ring, the operation is complicated and requires a large number of operation steps. In addition, in order to arrange a plurality of rolling elements evenly, for example, a dedicated manufacturing device such as an air injection device described in the prior art is required, which requires a large amount of equipment cost. Therefore, the manufacturing cost of the rolling bearing may be high.

  Moreover, in the conventional bearing device, when the rolling bearing portion rotates, there is a possibility that the grease may be scattered to the outside from the gap between the inner ring and the outer ring. In addition, a large amount of outgas generated from the grease may be discharged to the outside from the gap between the inner ring and the outer ring. In particular, in the case where a bearing device is employed in an information recording and reproducing apparatus such as a hard disk, grease and outgassing adhere to the disk or the like, which causes the recording failure and reproduction failure of the disk and deterioration of parts. There is a fear. Therefore, there remains a problem in terms of suppressing the scattering of grease and the release of outgassing.

  Therefore, the present invention has an object of providing a bearing device which can be manufactured at low cost by a simple operation and can suppress grease scattering and outgassing, a method of manufacturing the bearing device, and an information recording and reproducing device provided with the bearing device. I assume.

In order to solve the above-mentioned subject, a bearing device of the present invention is provided with a shaft and a pair of rolling bearing parts arranged side by side in the axial direction of the shaft, and the pair of rolling bearing parts are respectively An inner ring disposed coaxially with the central axis of the shaft, an outer ring surrounding the inner ring from the outer side in the radial direction of the shaft, and a plurality of rolling elements rotatably held between the inner ring and the outer ring And the separation distance between the innermost portion of the rolling element in the radial direction and the central axis is a first separation distance, and the separation distance between the outermost part of the rolling element in the radial direction and the central axis is The outer radius of the inner end portion in the axial direction of the inner ring is smaller than the first separation distance, and the inner ring is directed outward in the axial direction from the inner side in the axial direction. Said first separation distance Comprising a wheel rotation plane inner Rimosoto radius is formed to be larger, the outer ring, together with the inner radius of the outer end portion in the axial direction is larger than the second distance, wherein The outer ring rolling surface is formed such that the inner radius is smaller than the second separation distance from the inner side to the outer side in the axial direction, and the outer radius of the inner ring is the inner ring rolling surface and the outer ring. The contact portion with the moving body gradually decreases toward the inner end, and the inner radius of the outer ring gradually increases from the contact portion between the outer ring rolling surface and the rolling element toward the outer end. There is provided a seal member which is attached to one of the members of the inner ring and the outer ring at the axially outer end of the pair of rolling bearing portions to enlarge the gap between the inner ring and the outer ring. On the tip side of the seal member It is characterized in that the bent portion is provided to bend toward the inside of the axial direction.

According to the present invention, the inner ring is formed such that the outer radius of the end portion on one side in the axial direction is smaller than the first separation distance, and the first separation distance from the one side to the other side in the axial direction The inner ring rolling surface is formed such that the outer radius is large, and the outer ring is formed such that the inner radius of the other end in the axial direction is larger than the second distance, and from the other side in the axial direction Since the outer ring rolling surface is formed such that the inner radius is smaller than the second separation distance toward one side, the rolling elements arranged in an annularly uniform arrangement are placed on the inner ring rolling surface in the axial direction By inserting the outer ring from the inner ring or placing the rolling elements uniformly arranged in an annular shape on the outer ring rolling surface and then inserting the inner ring from the axial direction, the rolling elements are provided between the inner ring rolling surface and the outer ring rolling surface Can be easily placed. As a result, the rolling elements are inserted between the inner ring and the outer ring while shifting the inner ring and the outer ring, and the conventional complicated work of evenly arranging the plurality of rolling elements in the circumferential direction is unnecessary, and a dedicated manufacturing device is not necessary. The rolling bearing can be manufactured with a simple operation. Therefore, the cost of the bearing device can be reduced.
Further, since the inner ring and the outer ring can be formed by moving the mold along the axial direction, for example, the cost can be reduced by forging or the like.
When the rolling element is inserted between the inner ring and the outer ring while shifting the inner ring and the outer ring as in the prior art, the number and size of the insertable rolling elements are determined by the size of the gap between the inner ring and the outer ring. It will be limited. On the other hand, according to the present invention, the outer ring is inserted from the axial direction after placing the rolling element on the inner ring rolling surface, or the inner ring is placed from the axial direction after placing the rolling element on the outer ring rolling surface By inserting, since a plurality of rolling elements are arranged between the inner ring rolling surface and the outer ring rolling surface, as in the prior art, the rolling is performed without being limited by the number and size of the gap between the inner ring and the outer ring. It is possible to place a moving body. Therefore, the rigidity of the bearing device can be set as desired.
Further, the seal member is attached to any one of the inner ring and the outer ring at the axially outer end of the pair of rolling bearing portions to close the gap between the inner ring and the outer ring. Since the bent portion which is bent inward in the axial direction is provided, the gap between the bent portion of the seal member and any other member of the inner ring and the outer ring can be made labyrinth-like. Therefore, it is possible to suppress the scattering of grease to the outside of the bearing device and the release of outgassing.

Further, the bent portion of the seal member is disposed along the peripheral surface of the outer ring .

According to the present invention, since the bent portion of the seal member is disposed along the circumferential surface of the outer ring, it functions as a barrier against the scattering of grease and the release of outgassing. Therefore, it is possible to suppress the scattering of grease to the outside of the bearing device and the release of outgassing. In addition, since the bent portion of the seal member is disposed so as to overlap the peripheral surface of either the inner ring or the outer ring when viewed in the radial direction, thinning of the bearing device (shortening of the axial direction) it can.

Further, a tip end of the bent portion is located inside the axial direction with respect to an outer top in the axial direction of the rolling element and is located in the axial direction compared with a position where the seal member is attached to the inner ring. It is characterized by being disposed inside .

According to the present invention, the tip end of the bending portion is disposed axially inward of the outer crest in the axial direction of the rolling element and axially inward of the position where the seal member is attached to the inner ring. As a result, the bent portion can be elongated in the axial direction, and can function as a barrier against grease splashing and outgassing. Therefore, it is possible to effectively suppress the scattering of the grease to the outside of the bearing device and the release of the outgas. Further, since the bent portion of the seal member is disposed so as to overlap with the rolling element when viewed from the radial direction, the bearing device can be further thinned (shortened in the axial direction).

  In addition, a retainer is disposed between the inner ring and the outer ring, and can hold the plurality of rolling elements so that the rolling elements can be rolled so as to be evenly arranged annularly, and the tip of the bent portion is in the axial direction of the retainer It is characterized in that it is arranged on the inner side in the axial direction with respect to the outer end portion in.

  According to the present invention, since the tip end of the bent portion is disposed axially inward of the outer end portion in the axial direction of the retainer, the bent portion can be elongated in the axial direction, and scattering of grease and release of outgassing can be achieved. Can act as a barrier to Therefore, it is possible to effectively suppress the scattering of the grease to the outside of the bearing device and the release of the outgas. Further, since the bent portion of the seal member is disposed so as to overlap with the retainer when viewed from the radial direction, the bearing device can be thinned (shortening in the axial direction).

  Further, the retainer includes a main body portion, and a plurality of pairs of claw portions which are erected from the main body portion along the axial direction and hold the rolling element so as to roll freely, and the main body portion is rotated It is characterized in that it is disposed closer to the seal member than the moving body.

  According to the present invention, by disposing the main body of the retainer on the sealing member side, the bent portion can be made longer in the axial direction, and it can function as a barrier against the scattering of grease and the release of outgassing, and the rolling element The body portion of the retainer can be disposed in the space between the and the seal member. Therefore, the thickness of the bearing device can be reduced while reliably suppressing the scattering of the grease to the outside of the bearing device and the release of the outgas.

  Further, in the method of manufacturing a bearing device according to the present invention, a first disposing step of disposing any one member of the inner ring and the outer ring of the first rolling bearing portion among the pair of rolling bearing portions; A retainer holding step of holding the plurality of rolling elements in a rollable manner on each of the holdable first and second retainers and arranging them in an annular arrangement; and with respect to one member of the first rolling bearing portion, A first rolling element arranging step of inserting and arranging the plurality of rolling elements together with the first retainer in the axial direction; and the first rolling bearing with respect to the plurality of rolling elements held by the first retainer And a second disposing step of inserting and arranging any other member of the inner ring and the outer ring in the axial direction of the inner ring, and the inner ring and the outer ring of the second rolling bearing portion of the pair of rolling bearing portions. The And a third disposing step of arranging the other member in the axial direction with respect to the other member of the first rolling bearing portion, and the plurality of the plurality from the axial direction with respect to the other member of the second rolling bearing portion. A second rolling element arranging step of inserting and arranging rolling elements together with the second retainer, and the inner ring and the outer ring of the second rolling bearing portion with respect to the plurality of rolling elements held by the second retainer And a fourth arranging step of inserting and arranging any one of the members from the axial direction.

According to the present invention, after arranging the plurality of rolling elements in an annular arrangement in advance in the retainer holding process, the plurality of rolling elements for the first and second retainers are arranged in the first rolling element arranging process and the second rolling element arranging process. Can be placed on the outer ring rolling surface and the inner ring rolling surface. Thus, as in the prior art, the rolling element is inserted between the inner ring and the outer ring while shifting the inner ring and the outer ring, and the conventional complicated work of evenly arranging the plurality of rolling elements in the circumferential direction is not necessary. The rolling bearing can be easily formed.
Therefore, according to the manufacturing method of the bearing device of the present invention, the manufacturing cost of the bearing device capable of suppressing the scattering of the grease and the release of the outgas as described above can be reduced and the cost can be reduced.
When the rolling element is inserted between the inner ring and the outer ring while shifting the inner ring and the outer ring as in the prior art, the number and size of the insertable rolling elements are determined by the size of the gap between the inner ring and the outer ring. It will be limited. On the other hand, according to the present invention, since the first arrangement step to the fourth arrangement step are provided, the outer ring is inserted from the axial direction after the rolling element is placed on the inner ring rolling surface, or the rolling element Since a plurality of rolling elements are disposed between the inner ring rolling surface and the outer ring rolling surface by inserting the inner ring from the axial direction after placing the ring on the outer ring rolling surface, the inner ring and the outer ring as in the prior art The rolling elements can be arranged without being limited by the number and size due to the gap between Therefore, the rigidity of the bearing device can be set as desired.

  Further, according to the information recording and reproducing apparatus of the present invention, the above-described bearing device, a housing for supporting an end portion of the bearing device, and a rotating member externally fitted to the outer ring and rotating around a central axis of the shaft And a slider mounted on the rotating member for recording and reproducing information with the magnetic recording medium.

  According to the present invention, since the bearing device that can be manufactured by a simple operation and can be reduced in cost is provided, the cost of the information recording and reproducing apparatus can be reduced. Further, since the bearing device capable of suppressing the scattering of the grease and the release of the outgas is provided, the reliability of the information recording and reproducing device can be improved.

According to the present invention, the inner ring is formed such that the outer radius of one end portion in the axial direction is smaller than the first separation distance, and the outer ring is outer than the first separation distance from one side to the other side in the axial direction The inner ring rolling surface is formed to have a large radius, and the outer ring is formed such that the inner radius of the other side end in the axial direction is larger than the second separation distance, and one side from the other side in the axial direction Since the outer ring rolling surface is formed such that the inner radius is smaller than the second separation distance toward the inner ring, the outer ring from the axial direction after the rolling elements arranged in an annularly uniform arrangement are placed on the inner ring rolling surface The rolling element can be easily inserted between the inner ring rolling surface and the outer ring rolling surface by inserting the inner ring on the outer ring rolling surface after inserting the rolling elements evenly arranged in the ring shape. Can be placed on As a result, the rolling elements are inserted between the inner ring and the outer ring while shifting the inner ring and the outer ring, and the conventional complicated work of evenly arranging the plurality of rolling elements in the circumferential direction is unnecessary, and a dedicated manufacturing device is not necessary. The rolling bearing can be manufactured with a simple operation. Therefore, the cost of the bearing device can be reduced.
Further, since the inner ring rolling surface and the outer ring rolling surface can be formed by moving the mold along the axial direction, the inner ring and the outer ring can be formed at low cost by, for example, forging.
When the rolling element is inserted between the inner ring and the outer ring while shifting the inner ring and the outer ring as in the prior art, the number and size of the insertable rolling elements are determined by the size of the gap between the inner ring and the outer ring. It will be limited. On the other hand, according to the present invention, the outer ring is inserted from the axial direction after placing the rolling element on the inner ring rolling surface, or the inner ring is placed from the axial direction after placing the rolling element on the outer ring rolling surface By inserting, since a plurality of rolling elements are arranged between the inner ring rolling surface and the outer ring rolling surface, as in the prior art, the rolling is performed without being limited by the number and size of the gap between the inner ring and the outer ring. It is possible to place a moving body. Therefore, the rigidity of the bearing device can be set as desired.
Further, the seal member is attached to any one of the inner ring and the outer ring at the axially outer end of the pair of rolling bearing portions to close the gap between the inner ring and the outer ring, and the tip is either the inner ring or the outer ring Since it is provided to overlap with the other, the gap between the inner ring and the outer ring can be reliably closed from the outside in the axial direction. Therefore, it is possible to suppress the scattering of grease to the outside of the bearing device and the release of outgassing.

It is a perspective view of the information recording and reproducing apparatus which concerns on embodiment. It is a side sectional view of a bearing device concerning a first embodiment. It is a perspective view of the 1st retainer and the 2nd retainer. It is a flowchart of the manufacturing process of a bearing apparatus. It is explanatory drawing of a sealing member assembly process. It is explanatory drawing of a 1st inner ring arrangement | positioning process. It is explanatory drawing of a retainer holding process. It is explanatory drawing of an outer ring assembly formation process. It is explanatory drawing of a 1st rolling element arrangement | positioning process. It is explanatory drawing of an outer ring assembly arrangement | positioning process. It is explanatory drawing of a 2nd rolling element arrangement | positioning process. It is explanatory drawing of a 2nd inner ring arrangement | positioning process and a precompression addition process. It is side surface sectional drawing of the bearing apparatus which concerns on the modification of 1st embodiment. It is side surface sectional drawing of the bearing apparatus which concerns on 2nd embodiment. It is a side sectional view of a bearing device concerning a third embodiment.

  Hereinafter, a bearing device, a method of manufacturing the bearing device, and an information recording and reproducing apparatus according to the first embodiment will be described. In addition, below, after demonstrating the information recording and reproducing apparatus which concerns on embodiment, the manufacturing method of a bearing apparatus and a bearing apparatus is demonstrated.

(Information recording and reproducing device)
FIG. 1 is a perspective view of an information recording and reproducing apparatus 1 according to the embodiment.
As shown in FIG. 1, the information recording and reproducing apparatus 1 is an apparatus that performs writing and reading on a disk (magnetic recording medium) D having a recording layer. The information recording / reproducing apparatus 1 includes an arm (turning member) 8, a head gimbal assembly 4 supported on the tip side of the arm 8, a slider 2 mounted on the tip of the head gimbal assembly 4, and a head gimbal assembly 4. An actuator (VCM: voice coil motor) 6 for scan movement, a spindle motor 7 for rotating the disk D, a control unit 5 for supplying a current modulated according to information to the slider 2, and these components are housed inside And a housing 9 for

  The housing 9 is made of a metal material such as aluminum, iron, stainless steel, etc., and has a box-like shape having an opening at the top, and stands vertically from the bottom 9a of a square in plan view and the peripheral edge of the bottom 9a. It is comprised by the surrounding wall (not shown) provided. Inside the housing 9 surrounded by the peripheral wall, an accommodation recess for accommodating the above-described components is formed. A spindle motor 7 is attached substantially at the center of the bottom 9a, and the disc D is detachably fixed by fitting a center hole into the spindle motor 7.

A bearing device 10 is disposed on the side of the disk D. The end of the bearing device 10 is supported by the bottom 9 a of the housing 9. An arm 8 is externally fitted and fixed to the outer peripheral surface of the bearing device 10. The proximal end of the arm 8 is connected to the actuator 6 described above.
The arm 8 extends parallel to the surface of the disk D from the proximal end toward the distal end.
The head gimbal assembly 4 is connected to the tip of the arm 8. The head gimbal assembly 4 includes a suspension 3 and a slider 2 mounted on the tip of the suspension 3 and disposed opposite to the surface of the disk D. The slider 2 includes a recording element for writing (recording) information on the disc D and a reproducing element for reading (reproducing) information from the disc D.

  In the information recording and reproducing apparatus 1 configured as described above, in order to record or reproduce information, the spindle motor 7 is first driven to rotate the disc D around the central axis L2 of the disc D. Further, the actuator 6 is driven to rotate the arm 8 about the bearing device 10 as a rotation center. Thereby, the slider 2 disposed at the tip of the head gimbal assembly 4 can be scanned and moved to each part of the surface of the disk D. Then, by driving the recording element or reproducing element of the slider 2, it is possible to record or reproduce information on the disc D.

(Bearing device of the first embodiment)
FIG. 2 is a side sectional view of the bearing device 10 according to the first embodiment. In FIG. 2, the housing 9 and the bottom 9 a of the housing 9 are illustrated by a two-dot chain line. Hereinafter, the direction along the axis of the bearing device 10 (that is, the axis of the shaft 20; hereinafter, referred to as "central axis L1") will be referred to as "axial direction". Further, in the axial direction, the inner side in the axial direction of the pair of rolling bearing portions 30 and 40 is referred to as "the inner side in the axial direction", and the outer side in the axial direction of the pair of rolling bearing portions 30 and 40 is the "outside of the axial direction" Call it Further, a direction orthogonal to the central axis L1 is referred to as "radial direction", and a direction circling around the central axis L1 is referred to as "circumferential direction".
As shown in FIG. 2, the bearing device 10 according to the first embodiment includes a shaft 20 erected on the bottom 9 a of the housing 9 and a pair of rolling bearing portions 30 disposed in line in the axial direction of the shaft 20, And 40.

The shaft 20 is a substantially cylindrical member extending along the central axis L1, and is formed of, for example, a metal material such as aluminum, iron, or stainless steel. As for the shaft 20, the bottom 9a side of the housing 9 is a base end, and the opposite side along the axial direction is a tip.
At the proximal end of the shaft 20, a flange portion 20a having a diameter larger than the diameter of the shaft 20 and a reduced diameter portion 20b having a diameter smaller than the diameter of the shaft 20 Are arranged in this order toward the. The reduced diameter portion 20 b is formed with a male screw (not shown) screwed to a female screw (not shown) formed on the bottom 9 a of the housing 9. The shaft 20 is erected on the bottom 9 a of the housing 9 by the above-mentioned screwing. At this time, the flange portion 20 a is in contact with the bottom portion 9 a of the housing 9 to position the shaft 20 in the height direction.

(Rolling bearing)
On the shaft 20, a pair of rolling bearing portions 30, 40 are arranged in line in the axial direction. The first rolling bearing portion 30 of the pair of rolling bearing portions 30 and 40 is disposed on the base end side of the shaft 20, and the second rolling portion of the pair of rolling bearing portions 30 and 40 is disposed on the distal end side of the shaft 20. The bearing portion 40 is disposed.

(First rolling bearing)
The first rolling bearing portion 30 includes a first inner ring 36 coaxially arranged with the central axis L1 of the shaft 20, a first outer ring 31 surrounding the first inner ring 36 from the outer side in the radial direction of the shaft 20, and A plurality of rolling elements 35 rotatably held between the inner ring 36 and the first outer ring 31, and a plurality of rolling elements 35 are rotatably held so as to be evenly arranged in an annular manner (a first retainer 60) And the seal member 25 attached to the first inner ring 36.
In the following, the distance between the innermost of the plurality of rolling elements 35 in the radial direction and the distance between the central axis L1 is defined as a first distance K1, and the outermost of the plurality of rolling elements 35 in the radial direction and the central axis The separation distance from L1 is defined as a second separation distance K2.

(First inner ring)
The first inner ring 36 is, for example, a substantially cylindrical member made of a metal material such as stainless steel, and is formed by, for example, forging or machining.
In the first inner ring 36, the outer radius of the axially inner end portion 36b is smaller than the first distance K1.
An inner ring rolling surface 39 is formed at an axial intermediate portion of the outer peripheral surface 37 of the first inner ring 36. The inner ring rolling surface 39 is formed to have an arc-shaped side cross-section so that the outer radius gradually becomes larger than the first separation distance K1 from the inner side to the outer side in the axial direction. The inner ring rolling surface 39 is formed over the entire circumference of the outer peripheral surface 37 of the first inner ring 36, and the outer surfaces of the plurality of annularly arranged rolling elements 35 can come into contact with each other.
Further, the radially outer edge of the outer end 36 a of the first inner ring 36 is notched over the entire circumference to form a stepped portion 38 that is recessed inward in the axial direction by one step. A seal member 25 described later is fitted in the stepped portion 38.

  The inner diameter of the first inner ring 36 is sized to be insertable into the shaft 20. In the present embodiment, the inner diameter of the first inner ring 36 is formed to be slightly larger than the outer diameter of the shaft 20. The first inner ring 36 is inserted into the shaft 20 and fixed to the flange portion 20 a of the shaft 20 by, for example, an adhesive. The inner diameter of the first inner ring 36 may be formed to be the same as or slightly smaller than the outer diameter of the shaft 20. In this case, the first inner ring 36 is inserted into the shaft 20 and fixed by press fitting.

The inner diameter of the first inner ring 36 is uniform while the outer diameter of the inner ring rolling surface 39 increases from the inner side to the outer side in the axial direction. Therefore, since the mold can be slid along the axial direction to form the first inner ring 36, forging is preferable when the outer shape of the first inner ring 36 is formed. Then, after forming the outer shape of the first inner ring 36 by forging, the first inner ring 36 can be formed by cutting only the inner ring rolling surface 39. As described above, since the number of steps for machining can be significantly reduced as compared with the case where the first inner ring 36 is formed only by cutting, the manufacturing cost can be reduced.
The axially inner end portion 36b of the first inner ring 36 is axially outer than the inner end portion 31b of the first outer ring 31 described later, and the contact between the inner ring rolling surface 39 and the rolling elements 35 described later It is disposed inside the axial direction of the part. Thereby, since the axial length of the first inner ring 36 can be shortened, the bearing device 10 can be further reduced in size, weight and cost.

(First outer ring)
Similar to the first inner ring 36, the first outer ring 31 is a substantially cylindrical member made of, for example, a metal material such as stainless steel, and is formed by, for example, forging or machining.
In the first outer ring 31, the inner radius of the axially outer end portion 31a is formed larger than the second separation distance K2.
An outer ring rolling surface 34 is formed at an axial intermediate portion of the inner circumferential surface 33 of the first outer ring 31. The outer ring rolling surface 34 is formed to have an arc-shaped side cross-section so that the inner radius gradually becomes smaller than the second separation distance K2 from the outer side to the inner side in the axial direction. The outer ring rolling surface 34 is formed over the entire circumference of the inner circumferential surface 33 of the first outer ring 31, and the outer surfaces of the plurality of annularly arranged rolling elements 35 can come into contact with each other. The outer peripheral surface of the first outer ring 31 is formed so that the outer diameter is uniform in the axial direction. The axially outer end portion 31 a of the first outer ring 31 is disposed at the same position as the outer end portion 36 a of the first inner ring 36 in the axial direction.

(Rolling element)
The rolling element 35 is formed in a spherical shape by a metal material. The rolling elements 35 are disposed between the outer ring rolling surface 34 of the first outer ring 31 and the inner ring rolling surface 39 of the first inner ring 36, and roll along the rolling surfaces 34 and 39. ing. The radius of curvature of each rolling surface 34, 39 is formed to be slightly larger than the radius of curvature of the outer surface of the rolling element 35. The plurality of rolling elements 35 are uniformly arranged in an annular manner along the circumferential direction in a freely rolling manner by the first retainer 60.

(First retainer)
FIG. 3 is a perspective view of the first retainer 60 and the second retainer 70.
The first retainer 60 is a member made of, for example, resin or the like that holds each rolling element 35 in a rollable manner while rotating around the central axis L1 by the guidance by the first outer ring 31, the first inner ring 36 and the rolling elements 35. A main body portion 61 and a plurality of pairs of claw portions 63 integrally formed on the main body portion 61 are provided.
As shown in FIG. 3, the main body portion 61 is formed in an annular shape surrounding the first inner ring 36 from the outer side in the radial direction. For example, seven spherical ball pockets P into which the rolling elements 35 can be inserted at equal intervals in the circumferential direction are formed on the end face in the axial direction of the main body portion 61 by, for example, seven depressions.

  The main body portion 61 is provided with a plurality of pairs (seven pairs in the present embodiment) of claw portions 63 corresponding to the respective ball pockets P. Each pair of claws 63 can hold rolling elements 35 inserted in the ball pockets P in a freely rolling manner. The claws 63 of each pair are erected from the main body 61 along the central axis L1 (axial direction), face each other in the circumferential direction with the ball pockets P interposed therebetween, and from the base end toward the tip It is raised in the state curved in the shape of a circular arc so that distance of each other approaches.

As shown in FIG. 2, a plurality of (seven in the present embodiment) rolling elements 35 are held by ball pockets P (see FIG. 3) of the first retainer 60 in a state of being equally spaced in the circumferential direction Thus, it is disposed between the first inner ring 36 and the first outer ring 31. Grease (not shown) is filled in the gap between the first inner ring 36 and the first outer ring 31 in order to assist the smooth rolling of the rolling element 35, and the smooth rotation of the first rolling bearing portion 30 is ensured. It is done.
The main body portion 61 of the first retainer 60 is disposed on the opposite side to the below-described seal member 25 attached to the first inner ring 36 and is located inside in the axial direction.
Further, the inner radius of the first retainer 60 is larger than the maximum outer radius of the first inner ring 36, and the outer radius of the first retainer 60 is smaller than the minimum inner radius of the first outer ring 31. There is. By forming the first retainer 60 in this manner, the plurality of rolling elements 35 can be used as the inner ring rolling surface 39 of the first inner ring 36 without interference between the first retainer 60 and the first inner ring 36 and the first outer ring 31. And the outer ring rolling surface 34 of the first outer ring 31.

(Sealing member)
The seal member 25 is an annular plate-shaped member made of a metal material such as iron or aluminum, for example.
An inner portion in the radial direction of the seal member 25 is an elastically deformable portion 26 having a U-shaped cross-sectional view formed to be convex inward in the axial direction. The inner diameter of the seal member 25 is smaller than the outer diameter of the step portion 38 of the first inner ring 36. Thereby, the seal member 25 is fitted and fixed to the step portion 38 of the first inner ring 36 in a state where the elastically deformable portion 26 is elastically deformed.
The outer diameter of the seal member 25 is smaller than the inner diameter of the outer end 31 a of the first outer ring 31. Thereby, the seal member 25 can close the gap between the first inner ring 36 and the first outer ring 31 from the outside in the axial direction on the inner side in the radial direction than the first outer ring 31.

Further, on the tip end side of the seal member 25, a bending portion 27 which bends inward in the axial direction is provided. The bending portion 27 is formed to be bent inward in the axial direction, and the tip end 28 points inward in the axial direction.
The bent portion 27 is spaced apart from the first outer ring 31 by a predetermined distance inward in the radial direction, and is disposed along the inner circumferential surface 33 of the first outer ring 31. The tip end 28 of the bending portion 27 is spaced apart from the rolling element 35 and is axially inside of the top T of the rolling element 35 located on the outermost side in the axial direction, and the tip end of the claw portion 63 of the first retainer 60 And at substantially the same position in the axial direction. Further, the bent portion 27 of the seal member 25 is disposed so as to overlap the rolling element 35 when viewed from the outer side in the radial direction. Thus, the gap formed by the bent portion 27 of the seal member 25, the rolling element 35, and the first outer ring 31 has a labyrinth shape.

(Second rolling bearing)
The second rolling bearing portion 40 includes a second inner ring 46 coaxially arranged with the central axis L1 of the shaft 20, a second outer ring 41 surrounding the second inner ring 46 from the outer side in the radial direction of the shaft 20, and a second outer ring A plurality of rolling elements 35 rotatably held between the inner ring 46 and the second outer ring 41, a second retainer 70 for evenly arranging the plurality of rolling elements 35 in a ring shape, and a second inner ring 46 And a seal member 25 attached to the In the present embodiment, the second inner ring 46, the second outer ring 41, the plurality of rolling elements 35, the second retainer 70 and the seal member 25 of the second rolling bearing portion 40 are respectively the first inner ring 36 of the first rolling bearing portion 30. The first outer ring 31, the plurality of rolling elements 35, the first retainer 60, and the seal member 25 have the same shape. A stepped portion 48 is provided at the outer end 46 a of the second inner ring 46, and the seal member 25 is fitted in the same manner as the first inner ring 36. The second rolling bearing portion 40 is disposed to be plane-symmetrical to the first rolling bearing portion 30. The detailed description of the second rolling bearing portion 40 is omitted.

(sleeve)
In the present embodiment, the first outer ring 31 and the second outer ring 41 are respectively fixed by the sleeve 51 so as not to move relative to each other. The sleeve 51 is a substantially cylindrical member made of a metal material such as aluminum, iron or stainless steel, and is formed by forging, machining or the like. The sleeve 51 includes a cylindrical main body cylindrical portion 52 and a spacer portion 53 projecting radially inward at an axial intermediate portion of the main body cylindrical portion 52.
The inner diameter of the sleeve 51 is larger than the outer diameters of the first outer ring 31 and the second outer ring 41 so that the first outer ring 31 and the second outer ring 41 can be inserted and arranged inside the main cylindrical portion 52 except for the spacer portion 53. It is formed to be large. Both outer end portions 51a and 51b of the sleeve 51 are substantially flush with the outer end portion 31a of the first outer ring 31 and the outer end portion 41a of the second outer ring 41, respectively.

The spacer portion 53 has a predetermined thickness in the axial direction, and is formed so that the inner diameter thereof is substantially the same as the inner diameter of the first outer ring 31 and the second outer ring 41, for example.
By interposing the spacer portion 53 between the first inner ring 36 and the second inner ring 46, the first outer ring 31 and the second outer ring 41 can be disposed in a state of being separated by a predetermined distance in the axial direction. Furthermore, while the separation distance between the first outer ring 31 and the second outer ring 41 is held by the spacer portion 53, the first inner ring 36 and the second inner ring 46 are fixed to the shaft 20 in a state of relatively pressing along the axial direction. As a result, preload can be applied to the first inner ring 36 and the second inner ring 46.

  The first outer ring 31 and the second outer ring 41 are inserted into the sleeve 51 and fixed to the spacer portion 53 by, for example, an adhesive or the like in a state in which the first outer ring 31 and the second outer ring 41 abut. Thus, the sleeve 51, the first outer ring 31 and the second outer ring 41 are integrally formed to constitute the outer ring assembly 50. By providing the sleeve 51, the outer diameter of the bearing device 10 can be made uniform. Further, even when the arm 8 (see FIG. 1) is externally fitted to the sleeve 51, relative displacement does not occur on the central axes of the first outer ring 31 and the second outer ring 41. Therefore, the arm 8 (see FIG. 1) can be attached to the bearing device 10 with high accuracy, so that a high-performance information recording and reproducing apparatus 1 (see FIG. 1) can be formed.

The first rolling bearing portion 30 and the second rolling bearing portion 40 formed as described above are configured such that the inner end 36 b of the first inner ring 36 and the inner end 46 b of the second inner ring 46 do not interfere with each other. They are arranged side by side along the axial direction of the shaft 20. In addition, the first inner ring 36 of the first rolling bearing portion 30 and the second inner ring 46 of the second rolling bearing portion 40 are fixed to the sleeve 51 by, for example, an adhesive in a state where a preload is applied.
The fixing method of the first inner ring 36 and the second inner ring 46 with the shaft 20 and the fixing method of the first outer ring 31 and the second outer ring 41 with the sleeve 51 are not limited to the adhesive. Therefore, for example, the first inner ring 36 and the second inner ring 46 may be fixed to the shaft 20 and the first outer ring 31 and the second outer ring 41 may be fixed to the sleeve 51 by press fitting, laser welding or the like. Thereby, the first inner ring 36 and the second inner ring 46 can be fixed to the shaft 20 without using an adhesive, and the first outer ring 31 and the second outer ring 41 can be fixed to the sleeve 51. Therefore, the generation of outgassing from the adhesive can be prevented, and defects in the information recording and reproducing apparatus 1 (see FIG. 1) caused by the outgassing can be prevented.

(Method of manufacturing bearing device)
Subsequently, a method of manufacturing the bearing device 10 of the first embodiment will be described.
FIG. 4 is a flowchart of the manufacturing process (manufacturing method) of the bearing device 10 of the first embodiment.
As shown in FIG. 4, the manufacturing process of the bearing device 10 includes a seal member assembling step S9, a first inner ring arranging step S11 (corresponding to “first arranging step” in the claims), and a retainer holding step S13. An outer ring assembly forming step S15, a first rolling element arranging step S17, an outer ring assembly arranging step S19 (corresponding to "second arranging step" and "third arranging step" in the claims), and a second rotation A moving body disposing step S21, a second inner ring disposing step S23 (corresponding to “fourth disposing step” in the claims), and a preload applying step S25 are provided. Below, each process is demonstrated.

(Sealing member assembling step S9)
FIG. 5 is an explanatory view of the seal member assembling step S9.
First, as shown in FIG. 5, a seal member assembling step S9 of assembling the seal member 25 to the first inner ring 36 and the second inner ring 46 is performed.
In the seal member assembling step S9, the elastically deformable portion 26 of the seal member 25 is inserted into the stepped portion 38 of the first inner ring 36 and the stepped portion 48 of the second inner ring 46, respectively. As a result, the seal member 25 is elastically deformed by the elastically deformable portion 26, and is externally fitted and fixed to the outer end portions 36a and 46a of the first inner ring 36 and the second inner ring 46, respectively.

(First inner ring placement process S11)
FIG. 6 is an explanatory view of the first inner ring arranging step S11.
Next, as shown in FIG. 6, of the first inner ring 36 and the second inner ring 46 (see FIG. 2) to which the seal member 25 is assembled, the first inner ring 36 is inserted into the shaft 20 together with the seal member 25. A first inner ring arranging step S11 of arranging the first inner ring 36 on the outer side in the axial direction is performed.
In the first inner ring disposing step S11, the shaft 20 is disposed upright on a jig (not shown), and an adhesive is applied to the outer peripheral surface of the shaft 20. Next, with the outer end portion 36 a of the first inner ring 36 disposed on the side of the flange portion 20 a of the shaft 20, the first inner ring 36 is inserted into the shaft 20 along the axial direction. Then, the first inner ring 36 is pushed in, and the outer end 36 a is placed in contact with the flange portion 20 a of the shaft 20. Thereafter, the adhesive is solidified and the first inner ring 36 is fixed to the shaft 20. Above, 1st inner ring arrangement | positioning process S11 is complete | finished.

(Retainer holding step S13)
FIG. 7 is an explanatory view of the retainer holding step S13.
Subsequently, as shown in FIG. 7, a retainer holding step S13 is performed in which the plurality of rolling elements 35 are rotatably held by the first retainer 60 and the second retainer 70 and uniformly arranged in an annular shape.
In the retainer holding step S13, the rolling element 35 is pushed in between the pair of claws 63 of the first retainer 60, and the rolling element 35 is incorporated into the ball pocket P of the main body 61 of the first retainer 60. The pair of claws 63 elastically deform outward by the pressing force when the rolling element 35 is pushed. Thereby, the rolling element 35 can be inserted between the pair of claws 63 and can be incorporated into the ball pocket P. In addition, when the rolling element 35 is inserted into the ball pocket P, the pair of claws 63 is elastically restored and deformed to the original state and the opening diameter is narrowed. It can hold | maintain rolling freely by a pair of claw part 63. Similarly, by incorporating a plurality of (seven in the present embodiment) rolling elements 35 into the first retainer 60, the plurality of rolling elements 35 can roll freely in a state where they are equally arranged in the circumferential direction by the first retainer 60. It is held. Furthermore, similarly, when a plurality of (seven in the present embodiment) rolling elements 35 are incorporated into the second retainer 70, the retainer holding step S13 ends.

  The retainer holding step S13 may be performed before the sealing member assembling step S9 or the first inner ring arranging step S11. Further, in the present embodiment, the incorporation of the rolling element 35 into the first retainer 60 and the second retainer 70 is performed in one step (retainer holding step S13), but may be performed in another step. Specifically, it is divided into a first retainer holding step of incorporating the rolling element 35 into the first retainer 60 and a second retainer holding step of incorporating the rolling element 35 into the second retainer 70, and each retainer holding step is performed at different timings. You may go.

(Outer ring assembly forming step S15)
FIG. 8 is an explanatory view of the outer ring assembly forming step S15.
Subsequently, as shown in FIG. 8, the first outer ring 31 and the second outer ring 41 are fixed to the sleeve 51 so as not to move relative to each other, and an outer ring assembly forming step S15 of forming the outer ring assembly 50 is performed.
In the outer ring assembly forming step S <b> 15, first, an adhesive is applied to the inner peripheral surface of the main body cylindrical portion 52 of the sleeve 51. As an adhesive agent apply | coated to the internal peripheral surface of the main body cylinder part 52 of the sleeve 51, an anaerobic adhesive agent is suitable, for example. Next, the first outer ring 31 and the second outer ring 41 are inserted into the sleeve 51 inward from the outer side in the axial direction. Then, the first outer ring 31 and the second outer ring 41 are pushed in until the inner end 31 b of the first outer ring 31 and the inner end 41 b of the second outer ring 41 abut against the spacer portion 53. When the adhesive is cured, the sleeve 51, the first outer ring 31 and the second outer ring 41 are integrally formed to constitute the outer ring assembly 50. Above, outer ring assembly formation process S15 is completed.
The outer ring assembly forming step S15 may be performed at least before the outer ring assembly arranging step S19. Further, in the present embodiment, the first outer ring 31 and the second outer ring 41 are incorporated into the sleeve 51 in one step (the outer ring assembly forming step S15), but may be divided into separate steps.

(First rolling element placement step S17)
FIG. 9 is an explanatory view of the first rolling element arranging step S17.
Subsequently, as shown in FIG. 9, the plurality of rolling elements 35 are inserted into the first inner ring 36 together with the first retainer 60 from the inside in the axial direction, and the plurality of rolling elements are formed on the inner ring rolling surface 39 of the first inner ring 36. A first rolling element placement step S17 for placing 35 is performed.
At this time, while the tip end of the claw portion 63 of the first retainer 60 is disposed on the flange portion 20a side of the shaft 20 and the main body portion 61 of the first retainer 60 is disposed on the tip end side of the shaft 20, a plurality of rolling elements The first retainer 60 and the first retainer 60 are inserted into the first inner ring 36. Thereby, the main body 61 of the first retainer 60 is disposed inside in the axial direction.
Here, since the inner radius of the first retainer 60 is formed larger than the maximum outer radius of the first inner ring 36, the rolling elements 35 are held by the first retainer 60 and arranged in an annular uniform arrangement. The rolling element 35 can be inserted from the inside in the axial direction together with the first retainer 60 and mounted on the inner ring rolling surface 39 without interference between the first retainer 60 and the first inner ring 36. Further, the outer radius of the inner end portion 36b of the first inner ring 36 is formed smaller than the first distance K1. Therefore, in the first rolling element disposing step S17, the plurality of rolling elements 35 can be easily inserted from the inside in the axial direction without interference with the first retainer 60 and the inner end portion 36b of the first inner ring 36. Further, the inner ring rolling surface 39 of the first inner ring 36 is formed such that the outer radius thereof becomes gradually larger than the first separation distance K1 from the inner side to the outer side in the axial direction. Therefore, in the first rolling element arranging step S17, by inserting the plurality of rolling elements 35 together with the first retainer 60 into the first inner ring 36, the plurality of rolling elements 35 can be easily mounted on the inner ring rolling surface 39. Moreover, since the plurality of rolling elements 35 are evenly arranged and held in a relatively immovable manner by the first retainer 60, the plurality of rolling elements 35 are placed on the inner ring rolling surface 39 without using a jig or the like. Can be held in Thus, according to the first rolling element disposing step S17 of the present embodiment, the plurality of rolling elements 35 can be easily disposed on the outer side in the radial direction of the first inner ring 36. Above, 1st rolling element arrangement | positioning process S17 is complete | finished.

(Outer ring assembly placement step S19)
FIG. 10 is an explanatory view of the outer ring assembly disposing step S19.
Subsequently, as shown in FIG. 10, an outer ring assembly disposing step S19 of inserting the outer ring assembly 50 into the first inner ring 36 from the inner side in the axial direction is performed.
Here, since the outer radius of the first retainer 60 is formed to be smaller than the minimum inner radius of the first outer ring 31, the first outer ring 31 is inserted in a state where the rolling elements 35 are uniformly arranged in an annular shape. By doing so, the rolling element 35 can be easily brought into contact with the outer ring rolling surface 34 without the first retainer 60 and the first outer ring 31 interfering with each other.
Further, the outer radius of the outer end portion 31 a of the first outer ring 31 is formed larger than the second separation distance K2. Therefore, in the outer ring assembly arranging step S19, the first outer ring 31 can be easily inserted into the first inner ring 36 from the inner side in the axial direction without interfering with the plurality of rolling elements 35. Further, the outer ring rolling surface 34 of the first outer ring 31 is formed such that the inner radius becomes gradually smaller than the second separation distance K2 from the outer side in the axial direction toward the inner side. Therefore, in the outer ring assembly arranging step S19, when the outer ring assembly 50 is inserted into the first inner ring 36 from the inner side in the axial direction, the outer ring rolling surface 34 of the first outer ring 31 can contact the plurality of rolling elements 35 . As a result, the outer ring assembly 50 is positioned at a predetermined position in the axial direction, so the outer ring assembly 50 is held in a state in which the outer ring rolling surface 34 is in contact with the plurality of rolling elements 35 without using a jig or the like. It can hold.
In the present embodiment, since the sleeve 51, the first outer ring 31 and the second outer ring 41 are fixed to each other to form the outer ring assembly 50, the first inner ring 36 is axially fixed to the outer ring assembly 50. By inserting from the inner side, the outer ring rolling surface 34 of the first outer ring 31 can be brought into contact with the rolling elements 35 and the second outer ring 41 can be arranged on the outer side in the axial direction. That is, in the outer ring assembly disposing step S19, the first outer ring is disposed such that the first outer ring 31 is disposed on the outer side in the radial direction of the first inner ring 36 and the outer ring rolling surface 34 of the first outer ring 31 abuts on the rolling elements 35. Step S19A (corresponding to the “second arrangement step” in the claims) and a second outer ring arrangement step S19B in which the second outer ring 41 is axially connected to the first outer ring 31 and arranged on the outer side in the axial direction And the third placement step) are performed simultaneously.
As described above, according to the outer ring assembly disposing step S19 of the present embodiment, the outer ring assembly 50 configured of the sleeve 51, the first outer ring 31, and the second outer ring 41 can be easily made outside of the first inner ring 36 in the radial direction. Can be placed on Above, outer ring assembly placement process S19 is completed.

(Second rolling element placement step S21)
FIG. 11 is an explanatory view of the second rolling element placement step S21. Subsequently, as shown in FIG. 11, the plurality of rolling elements 35 are inserted together with the second retainer 70 from the outside in the axial direction into the second outer ring 41 of the outer ring assembly 50. The 2nd rolling element arrangement process S21 which mounts a plurality of rolling elements 35 is performed.
At this time, with the main body portion 61 of the second retainer 70 disposed on the flange portion 20 a side of the shaft 20 and the tip end of the claw portion 63 of the second retainer 70 disposed on the tip end side of the shaft 20, a plurality of rolling elements The second retainer 70 is inserted into the second outer ring 41 together with the second retainer 70. Thereby, the main body 61 of the second retainer 70 is disposed inside in the axial direction.
Here, since the outer radius of the second retainer 70 is formed to be smaller than the minimum inner radius of the second outer ring 41, the rolling elements 35 are inserted into the second outer ring 41 in a state where they are uniformly arranged in an annular shape. Thus, the rolling element 35 can be easily mounted on the outer ring rolling surface 44 without interference between the second retainer 70 and the first outer ring 31.
Further, the inner radius of the outer end portion 41a of the second outer ring 41 disposed outside in the axial direction is formed larger than the second separation distance K2. Therefore, in the second rolling element arranging step S21, the plurality of rolling elements 35 can be easily inserted together with the second retainer 70 without interference with the outer end 41a of the second outer ring 41. Further, the outer ring rolling surface 44 of the second outer ring 41 is formed so that the inner radius becomes smaller gradually than the second separation distance K2 from the outer side in the axial direction toward the inner side. Therefore, in the second rolling element arranging step S21, the plurality of rolling elements 35 can be easily formed on the outer ring rolling surface 44 by inserting the plurality of rolling elements 35 together with the second retainer 70 into the second outer ring 41 from the outside in the axial direction. Can be placed on Moreover, since the plurality of rolling elements 35 are evenly arranged and held in a relatively non-movable manner by the second retainer 70, the plurality of rolling elements 35 can be used as the outer ring of the second outer ring 41 without using a jig or the like. It can be held in the state of being placed on the surface 44. Thus, according to the second rolling element disposition step S21 of the present embodiment, the plurality of rolling elements 35 can be easily disposed on the inner side in the radial direction of the second outer ring 41. Above, 2nd rolling element arrangement | positioning process S21 is complete | finished.

(Second inner ring placement step S23)
FIG. 12 is an explanatory view of a second inner ring placement step S23 and a preload application step S25. Subsequently, as shown in FIG. 12, the second inner ring arranging step of inserting the second inner ring 46 with the seal member 25 together with the seal member 25 into the shaft 20 and arranging the second inner ring 46 on the axially outer side. Perform S23. In the second inner ring disposing step S23, the inner end 46b of the second inner ring 46 is disposed on the flange 20a side of the shaft 20, and the outer end 46a of the second inner ring 46 is disposed on the distal end of the shaft 20. , And the second inner race 46 is inserted along the axial direction of the shaft 20.
Here, since the inner radius of the second retainer 70 is formed to be larger than the minimum outer radius of the second inner ring 46, the second inner ring 46 is inserted in a state where the rolling elements 35 are uniformly arranged in an annular manner. By doing this, the rolling element 35 can be easily brought into contact with the inner ring rolling surface 49 without the second retainer 70 and the second inner ring 46 interfering with each other.
In addition, the outer radius of the inner end 46b of the second inner ring 46 disposed axially outside is smaller than the first distance K1. Therefore, in the second inner ring arranging step S23, the inner end 46b of the second inner ring 46 can be easily inserted without interfering with the plurality of rolling elements 35. In addition, the inner ring rolling surface 49 of the second inner ring 46 is formed such that the outer radius thereof becomes gradually larger than the first separation distance K1 from the inner side to the outer side in the axial direction. Therefore, in the second inner ring disposing step S23, when the second inner ring 46 is inserted into the shaft 20 from the outside in the axial direction, the inner ring rolling surface 49 of the second inner ring 46 can abut on the plurality of rolling elements 35. Thereby, since the second inner ring 46 is positioned at a predetermined position in the axial direction, the second inner ring 46 is held in a state where the inner ring rolling surface 49 abuts against the plurality of rolling elements 35 without using a jig or the like. It can hold. As described above, according to the second inner ring arranging step S23 of the present embodiment, the second inner ring 46 can be easily arranged on the outer side in the radial direction of the shaft 20. Above, 2nd inner ring arrangement | positioning process S23 is complete | finished.

(Preload addition process S25)
Then, while pressing the first inner ring 36 and the second inner ring 46 relatively along the axial direction, a preload application step S25 of fixing to the shaft 20 is performed. Here, the first inner ring 36 and the second inner ring 46 are relatively pressed by pressing the second inner ring 46 toward the first inner ring 36 while the first inner ring 36 is fixed. The pressing of the second inner ring 46 is performed using a jig (not shown).
By pressing the second inner ring 46 of the second rolling bearing portion 40, the separation distance between the first inner ring 36 of the first rolling bearing portion 30 and the second inner ring 46 of the second rolling bearing portion 40 is shortened. Here, the first outer ring 31 of the first rolling bearing portion 30 and the second outer ring 41 of the second rolling bearing portion 40 are fixed to the sleeve 51 and integrally formed. Therefore, by pressing the second inner ring 46 inward in the axial direction, the rolling elements 35 of the second rolling bearing portion 40 press the outer ring rolling surface 44 of the second outer ring 41 and the first outer ring 31 It is pushed outward in the axial direction. Further, when the first outer ring 31 is pressed outward in the axial direction, the rolling elements 35 of the first rolling bearing portion 30 are pressed against the outer ring rolling surface 34 of the first outer ring 31, and the first inner ring 36 The inner ring rolling surface 39 of the

  Thus, by pressing the second inner ring 46 of the second rolling bearing portion 40 in the axial direction, the first inner ring 36 of the first rolling bearing portion 30 and the second inner ring 46 of the second rolling bearing portion 40 can be Preload is applied. Then, the second inner ring 46 of the second rolling bearing portion 40 is pressed until the adhesive hardens. When the adhesive is cured, the preload application step S25 is completed, and the bearing device 10 according to the first embodiment is completed.

  In the present embodiment, the seal member assembling step S9 is performed before the first inner ring arranging step S11. However, the seal member 25 may be assembled to the first inner ring 36 and the second inner ring 46. For example, the order of the seal member assembling step S9 is not particularly limited. Further, in the sealing member assembling step S9, the assembling of the sealing member 25 to the first inner ring 36 and the assembling of the sealing member 25 to the second inner ring 46 are performed in the same step. May be Specifically, the seal is divided into a first seal member assembling step of assembling the seal member 25 to the first inner ring 36 and a second seal member assembling step of assembling the seal member 25 to the second inner ring 46 The member assembly process may be performed at different timings. Therefore, for example, the first seal member assembling step of assembling the seal member 25 to the first inner ring 36 is performed before the first inner ring arranging step S11, and the second inner ring 46 is assembled with the seal member 25 after the second inner ring arranging step S23. The second seal member assembling step may be performed.

  In the first inner ring arranging step S11, the outer ring assembly forming step S15 and the second inner ring arranging step S23, the first inner ring 36 and the second inner ring 46 are fixed to the shaft 20 by using an adhesive. The outer ring 31 and the second outer ring 41 are fixed to the sleeve 51. On the other hand, the first inner ring 36 and the second inner ring 46 may be fixed to the shaft 20 and the first outer ring 31 and the second outer ring 41 may be fixed to the sleeve 51 by, for example, press fitting or laser welding. Thereby, the first inner ring 36 and the second inner ring 46 can be fixed to the shaft 20 without using an adhesive, and the first outer ring 31 and the second outer ring 41 can be fixed to the sleeve 51. Therefore, the generation of outgassing from the adhesive can be prevented, and defects in the information recording / reproducing apparatus 1 caused by the outgassing can be prevented.

(Effect of the first embodiment)
The first inner race 36 and the second inner race 46 are formed such that the outer radii of the axially inner end portions 36b and 46b are smaller than the first separation distance K1, and the first separation distance from the inside to the outside in the axial direction The first outer ring 31 and the second outer ring 41 are provided with inner ring rolling surfaces 39, 49 formed so that the outer radius gradually becomes larger than K1, and the first outer ring 31 and the second outer ring 41 have the inner radius of the axially outer end portions 31a, 41a The outer ring rolling surfaces 34 and 44 are formed to be larger than the second separation distance K2 and formed so that the inner radius is gradually smaller than the second separation distance K2 from the outer side to the inner side in the axial direction. Therefore, after the rolling elements 35 which are held in the first retainer 60 and annularly uniformly arranged are placed on the inner ring rolling surface 39 of the first inner ring 36, the first outer ring 31 is inserted from the axial direction. Hold and evenly arrange in a circle By placing the rolling elements 35 on the outer ring rolling surface 44 of the second outer ring 41 and inserting the second inner ring 46 from the axial direction, the inner ring rolling surfaces 39, 49 and the outer ring rolling surfaces 34, 44 The rolling elements 35 can be easily arranged between them. As a result, after inserting the rolling elements between the inner ring and the outer ring while shifting the inner ring and the outer ring, there is no need for the conventional complicated operation of uniformly arranging a plurality of rolling elements in the circumferential direction, and the first rolling can be easily performed. Since the bearing portion 30 and the second rolling bearing portion 40 can be formed, the cost of the bearing device 10 can be reduced.
Further, since the first inner ring 36, the second inner ring 46, the first outer ring 31 and the second outer ring 41 can be formed by moving the mold along the axial direction, for example, the cost can be reduced by forging.
When the rolling element is inserted between the inner ring and the outer ring while shifting the inner ring and the outer ring as in the prior art, the number and size of the insertable rolling elements are determined by the size of the gap between the inner ring and the outer ring. It will be limited. On the other hand, according to the present embodiment, after the rolling element 35 is placed on the inner ring rolling surface 39 of the first inner ring 36, the first outer ring 31 is inserted from the axial direction, or the rolling element 35 is After being placed on the outer ring rolling surface 44 of the outer ring 41, the second inner ring 46 is inserted from the axial direction, whereby a plurality of rolling elements 35 are formed between the inner ring rolling surfaces 39, 49 and the outer ring rolling surfaces 34, 44. Because the clearances between the inner ring and the outer ring are arranged as in the prior art, the rolling elements 35 can be arranged without being limited in number or size. Therefore, the rigidity of the bearing device 10 can be set as desired.
In addition, the seal member 25 is attached to the first inner ring 36 and the second inner ring 46 at the axially outer end of the pair of rolling bearing portions 30 and 40, and the gap between the first inner ring 36 and the first outer ring 31 The gap between the second inner ring 46 and the second outer ring 41 is closed, and a bent portion 27 bent inward in the axial direction is provided on the tip end side of the seal member 25. The gap between the bent portion 27 and the first outer ring 31 and the second outer ring 41 can be shaped like a labyrinth. Therefore, it is possible to suppress the scattering of grease to the outside of the bearing device 10 and the release of outgassing.

  Further, since the bent portions 27 of the seal member 25 provided at both axial ends of the bearing device 10 are disposed along the inner peripheral surfaces 33 and 43 of the first outer ring 31 and the second outer ring 41, respectively. It acts as a barrier to grease splashing and outgassing. Therefore, it is possible to suppress the scattering of grease to the outside of the bearing device 10 and the release of outgassing. Further, since the bent portion 27 of the seal member 25 is disposed so as to overlap with the inner peripheral surfaces 33 and 43 of the first outer ring 31 and the second outer ring 41 when viewed from the radial direction, thinning of the bearing device 10 is achieved. (Shortening of the axial direction) can be performed.

  Further, since the tip end 28 of the bending portion 27 is disposed axially inside the outer top T in the axial direction of the rolling element 35, the bending portion 27 can be elongated in the axial direction, so that the grease is scattered or outgassed. It can act as a barrier to release. Therefore, the scattering of grease to the outside of the bearing device 10 and the release of the outgas can be effectively suppressed. Further, since the bent portion 27 of the seal member 25 is disposed so as to overlap the rolling element 35 when viewed from the radial direction, the bearing device 10 can be further thinned (shortened in the axial direction).

  Further, by providing the sleeve 51, the rigidity of the pair of rolling bearing portions 30, 40 can be increased. In addition, since the first inner ring 36 and the second inner ring 46 are fixed to the shaft 20 in a state in which the preload is applied, the bearing device 10 can be formed by so-called inner ring preload. Thus, the resonance frequency (resonance point) of the bearing device 10 can be increased, so that the bearing device 10 capable of coping with high-speed rotation can be obtained in addition to the above-described effects.

Moreover, according to the method of manufacturing the bearing device 10 of the present embodiment, after the plurality of rolling elements 35 are held in advance by the first retainer 60 and the second retainer 70 in the retainer holding step S13, In the rolling element disposing step S17 and the second rolling element disposing step S21, the plurality of rolling elements 35 can be placed on the inner ring rolling surface 39 and the outer ring rolling surface 44 for the first retainer 60 and the second retainer 70. Thus, the plurality of rolling elements 35 can be evenly arranged at one time. Therefore, after inserting the rolling elements between the inner ring and the outer ring while shifting the inner ring and the outer ring as in the prior art, the plurality of rolling elements in the circumferential direction Since a complicated operation of uniform alignment is not necessary, the pair of rolling bearing portions 30 and 40 can be easily formed.
Therefore, according to the manufacturing method of the bearing device 10 of the present embodiment, the manufacturing cost of the above-described bearing device 10 capable of suppressing the scattering of grease and the release of the outgas can be reduced, and the cost can be reduced.
When the rolling element is inserted between the inner ring and the outer ring while shifting the inner ring and the outer ring as in the prior art, the number and size of the insertable rolling elements are determined by the size of the gap between the inner ring and the outer ring. It will be limited. On the other hand, according to the manufacturing method of the bearing device 10 of the present embodiment, the first inner ring arranging step S11, the first outer ring arranging step S19A, the second outer ring arranging step S19B, and the second inner ring arranging step S23 Since the rolling element 35 is placed on the inner ring rolling surface 39 of the first inner ring 36, the first outer ring 31 is inserted from the axial direction, or the rolling element 35 is placed on the outer ring rolling surface 44 of the second outer ring 41. Since the plurality of rolling elements 35 are disposed between the inner ring rolling surfaces 39, 49 and the outer ring rolling surfaces 34, 44 by inserting the second inner ring 46 from the axial direction after mounting, as in the prior art The rolling elements 35 can be disposed without being limited in number or size due to the gap between the inner ring and the outer ring. Therefore, the rigidity of the bearing device 10 can be set as desired.

  Further, according to the information recording and reproducing apparatus 1 of the present embodiment, since the bearing device 10 which can be manufactured by a simple operation and can be reduced in cost is provided, the cost of the information recording and reproducing apparatus 1 can be reduced. Further, since the bearing device 10 capable of suppressing the scattering of the grease and the release of the outgas is provided, the reliability of the information recording and reproducing device 1 can be improved.

(Modification of the first embodiment)
FIG. 13 is a side sectional view of a bearing device 10 according to a modification of the first embodiment.
Subsequently, a bearing device 10 according to a modification of the first embodiment will be described. In the following, description of the same components as in the first embodiment will be omitted, and only different components will be described.
In the first embodiment, the first outer ring 31 and the second outer ring 41 are inserted in and fixed to the sleeve 51, and the sleeve 51, the first outer ring 31 and the second outer ring 41 are integrally formed to constitute the outer ring assembly 50. (See Figure 2).
On the other hand, the first outer ring 31 and the second outer ring 41 may be integrally formed without providing a sleeve as in the modification of the first embodiment shown in FIG. In FIG. 13, the boundary between the first outer ring 31 and the second outer ring 41 is illustrated by a two-dot chain line.
According to the modification of the first embodiment, since the first outer ring 31 and the second outer ring 41 are integrally formed, cost reduction can be achieved by reducing the number of parts, and the pair of rolling bearing portions 30, 40 The rigidity can be increased, and the resonance frequency (resonance point) of the bearing device 10 can be increased. Therefore, in addition to the operation and effect of the first embodiment, the bearing device 10 capable of coping with low cost and high speed rotation can be obtained.

Second Embodiment
FIG. 14 is a side cross-sectional view of a bearing device 210 according to a second embodiment.
Subsequently, a bearing device 210 according to a second embodiment will be described.
In the bearing device 10 according to the first embodiment, the main body 61 of the first retainer 60 and the second retainer 70 is disposed on the inner side in the axial direction with respect to the rolling element 35, and the tip 28 of the bending portion 27 is a rolling element It was disposed axially inside the outer top T in the axial direction of 35 (see FIG. 2).
On the other hand, as shown in FIG. 14, in the bearing device 210 according to the second embodiment, the main body 61 of the first retainer 60 and the main body 61 of the second retainer 70 is disposed axially outside the rolling elements 35. And the bearing 28 according to the first embodiment in that the tip end 28 of the bending portion 27 is disposed axially inside the outer end of the main body 61 of the first retainer 60 and the second retainer 70. It is different from the device 10. In the following, description of the same components as in the first embodiment will be omitted, and only different components will be described. Moreover, since the 1st rolling bearing part 30 and the 2nd rolling bearing part 40 are the same structures except being arrange | positioned so that it may become surface-symmetrical mutually, detailed description is abbreviate | omitted.

The bent portion 27 of the seal member 25 in the first rolling bearing portion 30 is disposed along the inner circumferential surface 33 of the first outer ring 31 between the first outer ring 31 and the main body portion 61 of the first retainer 60 There is. The tip end 28 of the bent portion 27 is spaced apart from the rolling element 35 and disposed axially inside the outer end of the main body portion 61 of the first retainer 60.
Further, the bent portion 27 of the seal member 25 is disposed so as to overlap the first retainer 60 when viewed from the outer side in the radial direction. Thus, the gap formed by the bent portion 27 of the seal member 25, the main body portion 61 of the first retainer 60, and the first outer ring 31 has a labyrinth shape.

Since the main body portion 61 of the first retainer 60 and the second retainer 70 is disposed on the outer side in the axial direction of the rolling elements 35, the rolling elements 35 of the first rolling bearing portion 30 and the second rolling bearing portion 40 are There is no other member between the rolling elements 35. Therefore, the first rolling bearing portion 30 and the second rolling bearing portion 40 can be arranged close to each other in the axial direction.
According to the second embodiment, since the tip end 28 of the bending portion 27 is disposed axially inside the outer end in the axial direction of the first retainer 60 and the second retainer 70, the bending portion 27 is axially It can be elongated in direction and can act as a barrier to grease splashing and outgassing. Therefore, it is possible to effectively suppress the scattering of the grease to the outside of the bearing device 210 and the release of the outgas. Further, since the bent portion 27 of the seal member 25 is disposed so as to overlap the first retainer 60 and the second retainer 70 when viewed from the radial direction, thinning of the bearing device 210 (shortening in the axial direction) Can.
Furthermore, the main body 61 of the retainer 60 and the second retainer 70 are disposed in the space between the rolling element 35 and the seal member 25 by arranging the main body 61 of the first retainer 60 and the second retainer 70 on the seal member 25 side. Can be arranged. Therefore, the thickness of the bearing device 210 can be reduced while reliably suppressing the scattering of the grease to the outside of the bearing device 210 and the release of the outgas.

Third Embodiment
FIG. 15 is a side cross-sectional view of a bearing device 310 according to a third embodiment.
Subsequently, a bearing device 310 according to a third embodiment will be described.
In the bearing device 10 according to the first embodiment, the seal member 25 is provided to the first inner ring 36 and the second inner ring 46, and a preload is applied to the first inner ring 36 and the second inner ring 46 by so-called inner ring preload. (See Figure 2).
On the other hand, as shown in FIG. 15, in the bearing device 310 according to the third embodiment, the seal member 25 is provided on the first outer ring 31 and the second outer ring 41, and the first outer ring is made by so-called outer ring preload. It differs from the bearing device 10 according to the first embodiment in that a preload is applied to the third outer ring 41 and the second outer ring 41. In the following, description of the same components as in the first embodiment will be omitted, and only different components will be described.

In the first inner ring 36, the outer radius of the axially outer end portion 36a is smaller than the first distance K1. The inner ring rolling surface 39 is formed to have an arc-shaped side cross-section so that the outer radius gradually becomes larger than the first separation distance K1 from the outer side to the inner side in the axial direction.
In the first outer ring 31, the inner radius of the axially inner end portion 31b is formed larger than the second separation distance K2. The outer ring rolling surface 34 of the first outer ring 31 is formed to have an arc-shaped side surface cross section so that the inner radius gradually becomes smaller than the second separation distance K2 from the inner side to the outer side in the axial direction. The outer ring rolling surface 34 is formed over the entire circumference of the inner circumferential surface 33 of the first outer ring 31, and the outer surfaces of the plurality of annularly arranged rolling elements 35 can come into contact with each other.

The radially outer portion of the seal member 25 is an elastically deformable portion 26 having a U-shaped cross-sectional view that is formed to be convex inward in the axial direction. The outer diameter of the seal member 25 is smaller than the inner diameter of the step portion 38 of the first outer ring 31. Thus, the seal member 25 is fitted and fixed to the step portion 38 of the first outer ring 31 in a state in which the elastically deformable portion 26 is elastically deformed.
The inner diameter of the seal member 25 is larger than the outer diameter of the outer end 36 a of the first inner ring 36. Thereby, the seal member 25 can close the gap between the first inner ring 36 and the first outer ring 31 from the outer side in the axial direction on the outer side in the radial direction than the first inner ring 36.

The bent portion 27 of the seal member 25 is spaced apart from the first inner ring 36 by a predetermined distance in the radial direction and is disposed along the outer peripheral surface 37 of the first inner ring 36. The tip end 28 of the bending portion 27 is spaced apart from the rolling element 35 and is axially inside of the top T of the rolling element 35 located on the outermost side in the axial direction, and the tip end of the claw portion 63 of the first retainer 60 And at substantially the same position in the axial direction. Further, the bent portion 27 of the seal member 25 is disposed so as to overlap the rolling element 35 when viewed from the outer side in the radial direction. Thus, the gap formed by the bent portion 27 of the seal member 25, the rolling element 35 and the first inner ring 36 has a labyrinth shape.
A stepped portion 48 is provided at the outer end 41 a of the second outer ring 41, and the seal member 25 is fitted in the same manner as the first outer ring 31. The bent portion 27 of the seal member 25 is disposed along the outer peripheral surface 47 of the second inner ring 46. The second rolling bearing portion 40 is disposed to be plane-symmetrical to the first rolling bearing portion 30. The detailed description of the second rolling bearing portion 40 is omitted.

A spacer 55 is disposed between the first inner ring 36 of the first rolling bearing portion 30 and the second inner ring 46 of the second rolling bearing portion 40. The spacer 55 is, for example, a ring-shaped member made of a metal material such as aluminum, iron, stainless steel, etc., and is formed by forging, machining or the like.
The outer diameter of the spacer 55 is substantially the same as the outer diameter of the inner end portion 36b of the first inner ring 36 of the first rolling bearing portion 30 and the outer diameter of the inner end portion 46b of the second inner ring 46 of the second rolling bearing portion 40. It is formed to be Further, the inner diameter of the spacer 55 is formed to be substantially the same as the inner diameter of the first inner ring 36 and the inner diameter of the second inner ring 46 so as to be insertable into the shaft 20 together with the first inner ring 36 and the second inner ring 46 There is.
By interposing the spacer 55 between the first inner ring 36 and the second inner ring 46, the first rolling bearing portion 30 and the second rolling bearing portion 40 can be disposed in a state of being separated by a predetermined distance in the axial direction. Therefore, while keeping the separation distance between the first inner ring 36 and the second inner ring 46 by the spacer 55, the separation distance between the first outer ring 31 and the second outer ring 41 is shortened, and the first outer ring 31 and the second outer ring 41 Can be preloaded.

Similar to the spacer 55, the sleeve 51 is a substantially cylindrical member made of a metal material such as aluminum, iron, stainless steel, etc., and is formed by forging, machining or the like. The sleeve 51 and the first outer ring 31 and the second outer ring 41 are fixed, for example, by an adhesive or the like. By providing the sleeve 51, the outer diameter of the bearing device 310 can be made uniform. Therefore, since the arm 8 (see FIG. 1) can be attached to the bearing device 310 with high accuracy, the high-performance information recording and reproducing apparatus 1 (see FIG. 1) can be formed.
Thus, the seal member 25 can also be applied to the bearing device 310 in which the first outer ring 31 and the second outer ring 41 are preloaded by so-called outer ring preload. Therefore, scattering of grease to the outside of the bearing device 310 and release of outgas can be effectively suppressed, and the bearing device 310 can be thinned (shortening in the axial direction).

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the present invention.

The shape of the shaft 20 is not limited to each embodiment. Further, the shapes of the first retainer 60 and the second retainer 70, the number of the rolling elements 35 arranged, and the like are not limited to those of the embodiments. For example, in the first retainer 60 and the second retainer 70 of each embodiment, the claws 63 are erected from the main body 61 along the axial direction. On the other hand, the claws 63 may be erected outward in the radial direction or inward in the radial direction so as to be inclined from the main body 61 in the axial direction.
In each embodiment, the first retainer 60 and the second retainer 70 are provided, but without using the first retainer 60 and the second retainer 70, the inner ring rolling surfaces 39, 49 and the outer ring rolling surface 34 , 44, and a plurality of rolling elements 35 may be disposed.
Also, each member may be integrally formed as appropriate. Therefore, for example, in the third embodiment, the first inner ring 36 and the second inner ring 46 may be integrally formed without providing the spacer 55.

  Further, in the first embodiment, the modified example of the first embodiment, and the third embodiment, the tip end 28 of the bent portion 27 is axially inside the top portion T of the rolling element 35 and the first retainer 60 With respect to the tip end of the claw portion 63 of the second retainer 70, it is arranged at substantially the same position in the axial direction. On the other hand, the tip end 28 of the bent portion 27 may be disposed axially inside the claws 63 of the first retainer 60 and the second retainer 70.

  In each embodiment, the seal members 25 are provided at both outer end portions in the axial direction of the bearing devices 10, 210 and 310, but only at one outer end portion in the axial direction of the bearing devices 10, 210 and 310. The sealing member 25 may be provided.

  In the first embodiment, the modification of the first embodiment, and the third embodiment, the main body portion 61 of the first retainer 60 and the main body portion 61 of the second retainer 70 are disposed axially inward of the rolling elements 35, respectively. In the second embodiment, the main body portion 61 of the first retainer 60 and the main body portion 61 of the second retainer 70 are disposed axially outside of the rolling element 35, respectively, but the first retainer 60 and the second retainer The arrangement direction of 70 is not limited to each embodiment. Therefore, for example, the main body portion 61 of the first retainer 60 may be disposed axially outside of the rolling elements 35, and the body portion 61 of the second retainer 70 may be disposed axially inside of the rolling elements 35. .

  In addition, although the bearing device 10 is applied as the pivot shaft of the arm 8 of the information recording and reproducing device 1, the application of the bearing device 10 is not limited to the pivot shaft of the arm 8 of the information recording and reproducing device 1. For example, the bearing device 10 may be applied as a rotating shaft of the spindle motor 7 for rotating the disk D of the information recording / reproducing apparatus 1, or the bearing device 10 is applied as a rotating shaft of a polygon mirror for scanning a laser light source. You may

  In the first embodiment, the modification of the first embodiment, and the second embodiment, the first inner ring 36 and the second inner ring 46 are relatively pressed in the axial direction. The second inner ring 46 is fixed to the shaft 20 to apply a preload, and in the third embodiment, with the first outer ring 31 and the second outer ring 41 relatively pressed along the axial direction, the first outer ring 31 and the A so-called home position preload is adopted, which applies a preload by fixing the second outer ring 41 to the sleeve 51. On the other hand, for example, a biasing member is provided to hold the first inner ring 36 and the second inner ring 46 or the first outer ring 31 and the second outer ring 41 in a state of being relatively pressed along the axial direction. So-called constant pressure preload may be adopted.

  Also, each embodiment may be combined as appropriate. For example, while combining 2nd embodiment and 3rd embodiment, while applying pre-load to the 1st outer ring 31 and the 2nd outer ring 41, the main-body part 61 of the 1st retainer 60 and the main-body part 61 of the 2nd retainer 70 are It may be arranged outside the rolling element 35 in the axial direction.

  Further, in the first embodiment and the second embodiment, the first outer ring 31 and the second outer ring 41 are respectively provided via the spacer portion 53 of the sleeve 51, and the inner end portion 31 b of the first outer ring 31 and the The inner end 41 b of the second outer ring 41 was separated. On the other hand, for example, without providing the spacer portion 53 of the sleeve 51, the first outer ring 31 and the first outer ring 31 in a state where the inner end 31b of the first outer ring 31 and the inner end 41b of the second outer ring 41 are in contact. A second outer ring 41 may be provided. Also, for example, the sleeve 51 may be eliminated, and the first outer ring 31 and the second outer ring 41 may be provided via an annular spacer.

  In the third embodiment, the first inner ring 36 and the second inner ring 46 are provided via the spacers 55 respectively, and the inner end 36 b of the first inner ring 36 and the inner end 46 b of the second inner ring 46 are provided. Were separated. On the other hand, for example, without providing the spacer 55, the first inner ring 36 and the second inner ring 46 with the inner end 36b of the first inner ring 36 and the inner end 46b of the second inner ring 46 abutted. May be provided.

  In the first embodiment, the first outer ring 31 and the second outer ring 41 are fixed to the sleeve 51, and the arm 8 is fixed to the sleeve 51. However, without providing the sleeve 51, the first outer ring 31 and the second outer ring 41 are fixed. The arm 8 may be fixed directly to the second outer ring 41.

  Further, the inner ring rolling surfaces 39 and 49 and the outer ring rolling surfaces 34 and 44 in each embodiment and the modification of the first embodiment are formed in a curved surface shape in which the outer radius and the inner radius gradually change. On the other hand, for example, the inner ring rolling surfaces 39 and 49 and the outer ring rolling surfaces 34 and 44 may partially include a flat portion.

  In addition, without departing from the spirit of the present invention, it is possible to replace components in the above-described embodiment with known components as appropriate.

DESCRIPTION OF SYMBOLS 1 ... Information recording and reproducing apparatus 2 ... Slider 8 ... Arm (rotation member) 9 ... Housing 10, 210, 310 ... Bearing apparatus 20 ... Shaft 25 ... Seal member 27 ... bent portion 28 ... tip 30 ... first roller bearing (roller bearing) 31 ... first outer (outer ring) 31a ... outer end 31b ... inner end 33, · · Inner circumferential surface (peripheral surface) 34 · · · outer ring rolling surface 35 · · · rolling elements 36 · · · first inner ring (inner ring) 36a · · · outer end portion 36b · · · inner end portion 37 · · · · Outer peripheral surface (peripheral surface) 39 · · · inner ring rolling surface 40 · · · second rolling bearing portion (rolling bearing portion) 41 · · · second outer ring (outer ring) 41a · · · outer end portion 41b · · · Inner end 43: Inner circumferential surface (peripheral surface) 44: Outer ring rolling surface 46: Second Ring (inner ring) 46a ··· Outer end 46b ··· Inner end 47 · · · Outer peripheral surface (peripheral surface) 49 ··· Inner ring rolling surface 51 · · · Sleeve 51a, 51b · · · · (End) 60 ··· First retainer (retainer) 61 · · · Main body portion 63 · · · Claw portion 70 · · · Second retainer (retainer) D · · · · · · · (discs (magnetic recording medium) K1 · · · First separation distance K2 ... Second separation distance S11 ... First inner ring placement process (first placement process) S13 ... Retainer holding process S17 ... First rolling element placement process S19 ... Outer ring assembly Three-dimensional arrangement process (second arrangement process, third arrangement process) S19A ... first outer ring arrangement process (second arrangement process) S19B ... second outer ring arrangement process (third arrangement process) S21 ... second Rolling element placement step S23 ... second inner ring placement step ( Four placement step) T · · · top

Claims (5)

With the shaft,
A pair of rolling bearings disposed in the axial direction of the shaft;
Equipped with
The pair of rolling bearing portions are respectively disposed between the inner ring coaxially arranged with the central axis of the shaft, the outer ring surrounding the inner ring from the outer side in the radial direction of the shaft, and the rolling between the inner ring and the outer ring. And a plurality of rotatably held rolling elements;
A separation distance between the innermost portion of the rolling element and the central axis in the radial direction is taken as a first separation distance, and a separation distance between the outermost part of the rolling element in the radial direction and the central axis is taken as a second separation distance When
The inner ring is formed such that the outer radius of the inner end in the axial direction is smaller than the first distance, and the first distance from the inner side in the axial direction toward the outer side in the axial direction Also has an inner ring rolling surface formed to increase the outer radius,
The outer ring is formed such that the inner radius of the outer end in the axial direction is larger than the second distance, and the inner distance from the inner side to the outer side in the axial direction is more than the second distance An outer ring rolling surface formed to have a small radius,
The outer radius of the inner ring gradually decreases from the contact portion between the inner ring rolling surface and the rolling element toward the inner end.
The inner radius of the outer ring is gradually increased from the contact portion between the outer ring rolling surface and the rolling element toward the outer end,
A sealing member attached to the inner ring and closing a gap between the inner ring and the outer ring is provided at the axial outer end of the pair of rolling bearing portions.
A bending portion which is bent inward in the axial direction is provided on the tip side of the seal member,
The bent portion of the seal member is disposed along the circumferential surface of the outer ring,
The tip end of the bent portion is inside the axial direction with respect to the outer crest in the axial direction of the rolling element and inside the axial direction from a position where the seal member is attached to the inner ring . Bearing arrangement characterized in that it is arranged. The bearing device according to claim 1, wherein
A retainer disposed between the inner ring and the outer ring and capable of holding the plurality of rolling elements so as to be able to roll and uniformly arranged in an annular manner;
The tip end of the bent portion is disposed inward of the axial direction with respect to the axially outer end of the retainer. The bearing device according to claim 2, wherein
The retainer is
Body part,
A plurality of pairs of claws which are erected from the main body along the axial direction and hold the rolling element so as to roll freely;
Equipped with
A bearing device characterized in that the main body portion is disposed closer to the seal member than the rolling element. A method of manufacturing a bearing device according to claim 1, wherein
A first arranging step of arranging any one member of the inner ring and the outer ring of the first rolling bearing portion among the pair of rolling bearing portions;
A retainer holding step of rollingly holding the plurality of rolling elements on each of the first and second retainers capable of holding the rolling elements so as to arrange them in an annular pattern;
A first rolling element arranging step of inserting and arranging the plurality of rolling elements together with the first retainer in the axial direction with respect to one member of the first rolling bearing portion;
A second arranging step of inserting and arranging any one of the inner ring and the outer ring of the first rolling bearing portion from the axial direction with respect to the plurality of rolling elements held by the first retainer;
A third arrangement step of arranging any one of the inner ring and the outer ring of the second rolling bearing portion of the pair of rolling bearing portions in an axial direction with respect to the other member of the first rolling bearing portion When,
A second rolling element disposing step of inserting and arranging the plurality of rolling elements together with the second retainer in the axial direction with respect to the other member of the second rolling bearing portion;
A fourth arranging step of inserting and arranging any one member of the inner ring and the outer ring of the second rolling bearing portion from the axial direction with respect to the plurality of rolling elements held by the second retainer;
A method of manufacturing a bearing device, comprising: A bearing device according to claim 1;
A housing supporting an end of the bearing device;
A rotating member externally fitted to the outer ring and rotating around a central axis of the shaft;
A slider mounted on the rotating member for recording and reproducing information with a magnetic recording medium;
An information recording and reproducing apparatus comprising:

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