JP2009156421A - Sealed roll neck bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealed roll neck bearing high in mounting stiffness, excellent in assembly property with respect to a roll neck part, and high in sealing performance. <P>SOLUTION: The sealed roll neck bearing 40 has a sealing device 51 installed to outer peripheral faces 43d, 44d of abutment parts of a pair of inner rings 43, 44. The sealing device 51 has an elastic seal member 53 having a fitting part 54 and a radial lip part 55, and a core metal 52 disposed to cover at least the radially outside of the fitting part 54. The fitting part 54 is fitted to an outer peripheral face 43d of one inner ring to give the high mounting stiffness the sealing device 51, and the radial lip part 55 is brought into slide-contact with an outer peripheral face of the other inner ring to follow eccentricity of inner rings 43, 44 and secure high sealing performance. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a hermetic roll neck bearing, and more particularly to a hermetic roll neck bearing having excellent sealing performance, for example, used in a rolling mill for steel equipment.

  As shown in FIG. 9, a sealed roll neck bearing (four-row tapered roller bearing) 1 used in a hot rolling mill and a cold rolling mill of a steel facility is composed of an outer ring 2 and a double-row outer ring 3, and a pair of A row inner ring 4, an outer ring 2, a double row inner ring 4, and a plurality of tapered rollers 5 rotatably disposed between the double row outer ring 3 and the double row inner ring 4. The roll neck 7 is used after being loosely fitted (loose fit). At one end of the pair of double-row inner rings 4 on the shaft end side, a fillet ring 8 that is an inner ring pressing member is disposed to position the double-row inner rings 4 in the axial direction. A seal 9 such as an O-ring is disposed on the inner peripheral surface of the fillet ring 8 to seal between the outer peripheral surface of the roll neck portion 7.

  Chock seals 11 and 12 are disposed between the shaft side end of the chock (housing) 10 and the fillet ring 8, and between the roll side end of the chock 10 and the roll neck 7, respectively. Further, a seal holder 14 sealed with an O-ring 13 between the inner peripheral surface of the chock 10 is provided on the outer side portion of each outer ring 2, and an oil seal 15 fixed to the seal holder 14 is provided. However, the sealed roll neck bearing 1 is sealed in sliding contact with the outer peripheral surface of the double row inner ring 4.

  Such a sealed-type roll neck bearing 1 is used in a very severe usage environment in which a large load acts and the periphery is covered with scale-rolled water. Therefore, if the O-ring 9 or the chock seals 11 and 12 are damaged, water, foreign matter, etc. may enter the sealed roll neck bearing 1 from the inner peripheral surface side of the double-row inner ring 4 and the bearing life is shortened. There is a risk of becoming. Therefore, the durability of the seal members (O-ring 9 and chock seals 11 and 12) provided at both ends is cited as an issue. By improving the heat resistance of the rubber material and improving the lip shape design, water in the bearing, foreign matter, etc. Improvements have been made to the penetration of

  On the other hand, the double-row inner ring 4 of the sealed roll neck bearing 1 loosely fits with the roll neck portion 7 and is axially positioned by the fillet ring 8, but the seal 9 provided on the inner peripheral surface of the fillet ring 8. May be damaged by repeated attachment and detachment from the roll neck portion 7 for maintenance or the like. When the seal 9 is damaged, water, foreign matter and the like enter through the fitting surface loosely fitted from the shaft end side, and also enter the sealed roll neck bearing 1 from the abutting surfaces of the pair of double-row inner rings 4. There is a risk that. Therefore, the sealed roll neck bearing 1 generally employs a structure in which a sealing device (intermediate seal) 16 is provided at the abutting portion at the end of the double row inner ring 4 to prevent intrusion of water or the like.

  Further, as a design structure around the bearing in recent years, easy attachment / detachment of the fillet ring 8 is required, and a structure in which the seal 9 is not provided on the fillet ring 8 is increasing. Therefore, the amount of rolling water that passes through the inner peripheral surface of the fillet ring 8 and enters the inner peripheral surface of the double-row inner ring 4 (the fitting surface with the roll neck portion 7) also tends to increase. High sealing performance is required.

  Various structures have been proposed as sealing devices for such sealed roll neck bearings (see, for example, Patent Documents 1 to 3).

  As shown in FIG. 10, a sealing device 20 for a roll neck bearing of a rolling mill described in Patent Document 1 includes a cored bar 21 and an elastic sealing member 22, and is attached to annular stepped portions of inner rings 23 and 24. Yes. The elastic seal member 22 has two radial projections (radial lip portions) 26 and 27 provided on the inner peripheral surface thereof, and two axial projections 28 and 29 provided on both side surfaces. The radial protrusions 26 and 27 are in sliding contact with the small-diameter end outer peripheral surfaces 23a and 24a of the inner rings 23 and 24, and the axial protrusions 28 and 29 are in sliding contact with the large-diameter end surfaces 23b and 24b of the inner rings 23 and 24, Water and foreign matter entering from the butted surfaces 25 of the inner rings 23 and 24 are sealed.

As shown in FIG. 11, the sealing device 30 of the sealed four-row tapered roller bearing described in Patent Document 2 is disposed around the butted portion of a pair of inner rings 31 and 32 that face each other in the axial direction. In the sealing device 30, a cored bar 35 is integrally provided on the outer peripheral side of an annular sealing member 33 made of synthetic resin, and a pair of annular ribs (radial lip portions) 34 are formed on the inner peripheral side. The annular rib 34 is in sliding contact with the outer peripheral surfaces 31 a and 32 a of the extension portions of the inner rings 31 and 32 to seal the joint portion of the inner rings 31 and 32.
JP 2002-178013 A JP-A-6-17824 JP 55-47017 A

  By the way, the sealing devices 20 and 30 shown in FIG. 10 and FIG. 11 include radial lip portions 26, 27, and 34 of an elastic seal member integrally molded with metal cores 21 and 35, and inner rings 23, 24, 31, 32 has a structure that is slidably brought into contact with the outer peripheral surface of the seal 32, and even when a slight misalignment occurs during the work of inserting the inner rings 23, 24, 31, 32 into the seal devices 20, 30, the inner diameter of the seal Since the inner rings 23, 24, 31, and 32 are inserted along the lip, the assemblability is relatively good. On the other hand, since only the radial lip portions 26, 27, 34 are attached to the outer peripheral surface of the abutting portion of the inner ring end portion, there is a problem that the mounting rigidity of the seal devices 20, 30 is low. For this reason, particularly when the rolling mill is rolled at a high speed exceeding 1800 mpm, the sealing devices 20 and 30 that rotate together with the inner rings 23, 24, 31, and 32 (the seal fitting surfaces hardly slide). If centrifugal force or vibration acts on the lip, the behavior of the radial lip portions 26, 27, 34 occurs, the contact state between the radial lip portions 26, 27, 34 and the outer peripheral surface of the inner ring becomes unstable, and the sealing performance decreases. There's a problem.

  The present invention has been made in view of the above-mentioned problems, and an object thereof is to provide a hermetic roll neck bearing having high mounting rigidity, excellent assemblability to a roll neck portion, and high sealing performance. It is in.

The above object of the present invention is achieved by the following configurations.
(1) a plurality of outer rings;
Multiple inner rings,
A plurality of rollers disposed between the outer ring and the inner ring;
A sealing device disposed around both ends of the inner ring disposed so as to face each other, and having a metal core and an elastic seal member;
A sealed roll neck bearing comprising:
The inner peripheral surface of the elastic seal member has a fitting portion that fits with one outer peripheral surface of the both end portions, and a radial lip portion that makes sliding contact with the other outer peripheral surface of the both end portions,
The cored bar covers at least the outer side in the radial direction of the fitting portion on the outer peripheral side of the elastic seal member.
(2) The sealed roll neck bearing according to (1), wherein an inner diameter of the radial lip portion is smaller than an inner diameter of the fitting portion.
(3) The fitting portion is formed in a flat shape having a substantially uniform inner diameter,
One end of the metal core is located between the butted surfaces of the both end portions and the radial lip portion in the axial direction, and the sealed roll neck bearing according to (1) or (2).
(4) The fitting portion is formed in a substantially symmetrical curved surface shape in the axial direction,
One end of the metal core is located between the butted surfaces of the both end portions and the radial lip portion in the axial direction, and the sealed roll neck bearing according to (1) or (2).
(5) The fitting portion is formed in a tapered shape whose diameter is expanded on the opposite side to the radial lip portion,
One end of the cored bar extends in the axial direction beyond the radial lip, and the sealed roll neck bearing according to (1) or (2).

  According to the sealed roll neck bearing of the present invention, the sealing device disposed at both ends of the inner ring to be butt-arranged includes an elastic seal member having a fitting portion and a radial lip portion on the inner peripheral surface, and an elastic seal member On the outer peripheral side, it has a metal core that covers at least the radially outer side of the fitting portion. Then, by fitting the fitting portion to the outer peripheral surface of one of the inner rings, the seal device has high attachment rigidity and improves durability. In addition, by sliding the radial lip part on the outer peripheral surface of the other inner ring, it can follow the eccentricity of both inner rings and maintain high sealing performance even if centrifugal force or vibration acts on the sealing device during high-speed rotation. Can do.

  Embodiments of a sealed roll neck bearing according to the present invention will be described below in detail with reference to the drawings.

(First embodiment)
1 is a longitudinal sectional view of a main part of a sealed roll neck bearing according to a first embodiment of the present invention, FIG. 2A is an enlarged view of a portion surrounded by a circle II in FIG. 1, and FIG. FIG. 3 is a cross-sectional view of a main part of a single seal device, and FIG. 3 is a cross-sectional view of the seal device shown in FIG.

  As shown in FIG. 1, the sealed roll neck bearing (sealed four-row tapered roller bearing) 40 of the first embodiment includes a pair of outer rings 41 and a double-row outer ring 42, a pair of double-row inner rings 43 and 44, An outer ring 41 and double row inner rings 43 and 44, and a plurality of tapered rollers 45 disposed in four rows between the double row outer ring 42 and double row inner rings 43 and 44 and rotatably held by a cage 46 are provided. .

  Between the double row outer ring 42 arranged in the center in the axial direction and the outer ring 41 arranged on both sides in the axial direction, outer ring spacers 47 are arranged respectively, and the axial direction of the pair of outer rings 41 and the double row outer ring 42 Is positioned. Further, an annular seal holder 48 containing an oil seal 49 is disposed outside the outer ring 41 in the axial direction, and the outer circumferences of the small-diameter portions 43a and 44a extending axially outward from the double-row inner rings 43 and 44. A gap between the surfaces is sealed by an oil seal 49. Further, an O-ring 50 is attached to the outer peripheral surface of the seal holder 48 to seal a gap with a chock (not shown) (see FIG. 9).

  Referring also to FIG. 2, shoulder portions that are both ends of the pair of double-row inner rings 43 and 44 disposed so as to face each other are formed in a stepped shape and extend inward in the axial direction. Further, the abutting surfaces 43c and 44c of the small diameter end portions 43b and 44b are arranged so as to abut each other. A sealing device 51 is disposed on the outer peripheral surface side of the small diameter end portions 43b and 44b. The sealing device 51 includes, for example, a metal core 52 formed in a ring shape with metal and bent to have a substantially L-shaped cross section, and an annular elastic seal member 53 formed integrally with the metal core 52. . The material of the elastic seal member 53 is not particularly limited, but a rubber material having high elasticity, for example, nitrile rubber, acrylic rubber, fluorine rubber, or the like is used.

  On the inner peripheral surface of the elastic seal member 53, a fitting portion 54 formed in a flat shape having a substantially uniform inner diameter, and a radial lip portion 55 formed so as to protrude radially inward are provided in the axial direction. Are formed side by side. The inner diameter D2 of the radial lip portion 55 is slightly smaller than the inner diameter D1 of the fitting portion 54 (D2 <D1).

  In the sealing device 51, the fitting portion 54 is fitted to the outer peripheral surface 43d of the small diameter end portion 43b of one double row inner ring 43 (the left side double row inner ring in FIG. 2), and the radial lip portion 55 is the other double row. The inner ring 44 (the double row inner ring on the right side in FIG. 2) is fitted to the outer peripheral surface 44d of the small-diameter end portion 44b with a tightening margin. The radial lip portion 55 is in sliding contact with the outer peripheral surface 44d of the small diameter end portion 44b of the other double-row inner ring 44 with a certain tightening allowance.

  The core metal 52 is provided on the outer peripheral side of the elastic seal member 53, extends in the axial direction from the outer peripheral side of the radially inward flange portion 52a, and one end (right end portion in the figure) 52b has a small diameter end portion 43b in the axial direction. , 44b and the radial lip portion 55 are located between the butted surfaces 43c, 44c. That is, the cored bar 52 is formed so as to cover the outer side in the radial direction of the fitting part 54, and is not provided on the outer side in the radial direction of the radial lip part 55.

  The assembly of the seal device 51 to the bearing is performed by first hitting the fitting portion 54 of the seal device 51 with a soft hammer or the like using a mounting jig (for example, a batten, a ring or the like). One double-row inner ring 43 is press-fitted into the outer peripheral surface 43d of the small-diameter end portion 43b. By fitting the fitting portion 54 having a substantially uniform inner diameter into a flat shape into the outer peripheral surface 43d, the sealing device 51 is attached with high attachment rigidity. Next, the outer peripheral surface 44 d of the small diameter end portion 44 b of the other double-row inner ring 44 is fitted to the radial lip portion 55. The force required for this fitting can be fitted with a weak force about the weight of the double row inner ring 44.

  Further, since the radial lip portion 55 is fitted to the outer peripheral surface 44d of the small-diameter end portion 44b with an appropriate tightening margin, the outer peripheral surfaces 43d and 44d of the double-row inner rings 43 and 44 are slightly eccentric. This can be followed easily, and the sealing performance is maintained well. At this time, since the radial lip portion 55 is fitted with a tightening margin, the elastic radial lip portion 55 is elastically deformed.

  Therefore, as shown in FIG. 3B, when the cored bar 52 is formed so as to cover the radially outer side over the entire length of the fitting part 54 and the radial lip part 55, the cored bar 52 and the elastic seal are formed. Depending on the structure of the member 53, the size of the fastening margin of the radial lip portion 55, etc., the entire sealing device 51 is deformed as shown by the broken line in FIG. There is a possibility that the mounting rigidity of the lens slightly decreases. On the other hand, in the sealing device 51 of the present embodiment, since the cored bar 52 is not provided radially outward of the radial lip portion 55, only the vicinity of the radial lip portion 55 is shown as indicated by a broken line in FIG. Is locally elastically deformed (swells), and the mounting rigidity at the fitting portion 54 is prevented from being affected.

  As described above, according to the sealed-type roll neck bearing 40 of the present embodiment, the sealing device 51 is attached by fitting the fitting portion 54 into the outer peripheral surface 43d of the one double-row inner ring 43. 51 has a high mounting rigidity. Further, since the radial lip portion 55 having a tightening margin is fitted to the outer peripheral surface 44d of the other double-row inner ring 44, even if both the outer peripheral surfaces 43d and 44d are slightly eccentric, they can follow this. And high sealing performance is ensured. Furthermore, workability when inserting the sealing device 51 into the double-row inner ring 44 is also improved.

  Further, since the inner diameter D2 of the radial lip portion 55 is smaller than the inner diameter D1 of the fitting portion 54, the radial lip portion 55 is fitted to the outer peripheral surface 44d of the double row inner ring 44 with a large tightening margin, and both double row inner rings are fitted. By causing the radial lip portion 55 to follow the eccentricity of 43 and 44, higher sealing performance can be obtained.

  Further, the fitting portion 54 is formed in a flat shape having a substantially uniform inner diameter, and one end 52b of the cored bar 52 is in the axial direction with the butted surfaces 43c and 44c of the small diameter end portions 43b and 44b and a radial lip. The elastic deformation of the radial lip portion 55 caused by the fitting between the outer peripheral surface 44d of the double-row inner ring 44 and the radial lip portion 55 affects the mounting rigidity of the fitting portion 54. The sealing device 51 can ensure high mounting rigidity by the reliable fitting with the double row inner ring 43 at the fitting portion 54.

(Second Embodiment)
Next, a sealing device mounted on the sealed roll neck bearing of the second embodiment will be described with reference to FIG. FIG. 4 is an enlarged cross-sectional view of a main part of a hermetic roll neck bearing equipped with a sealing device according to a second embodiment of the present invention. In this embodiment, only the shape of the fitting portion of the sealing device is different from that of the first embodiment, and other configurations are the same as those of the first embodiment. The description will be simplified or omitted with corresponding reference numerals.

  The elastic sealing member 53 of the sealing device 51 according to the second embodiment includes a fitting portion 54 that protrudes inward and is formed in a curved surface that is substantially symmetrical in the axial direction, and a radial that protrudes inward in the radial direction. The lip portion 55 is formed side by side in the axial direction, the fitting portion 54 is fitted to the outer peripheral surface 43d of the small diameter end portion 43b of one double row inner ring 43, and the radial lip portion 55 is the other double row. The inner ring 44 is in sliding contact with the outer peripheral surface 44d of the small-diameter end 44b with a certain margin.

  One end 52b of the cored bar 52 is located between the butting surfaces 43c and 44c of the small diameter end portions 43b and 44b and the radial lip portion 55 in the axial direction. That is, the cored bar 52 is formed so as to cover only the radially outer side of the fitting part 54, and is not provided on the radially outer side of the radial lip part 55. Thus, by making the cross-sectional shape of the fitting portion 54 a gentle R shape, the fitting area with the outer peripheral surface 43d is increased to ensure high attachment rigidity and the insertion of the outer peripheral surface 43d is facilitated. The assembly is improved.

Accordingly, in the sealed roll neck bearing 40 of the present embodiment, the fitting portion 54 is formed in a curved surface that is substantially symmetrical in the axial direction, and one end of the cored bar 52 is formed by the small diameter end portions 43b and 44b in the axial direction. Since it is located between the abutting surfaces 43c, 44c and the radial lip portion 55, the elastic deformation of the radial lip portion 55 caused by the fitting between the outer peripheral surface 44d of the double row inner ring 44 and the radial lip portion 55 is as follows. The influence on the mounting rigidity of the fitting portion 54 can be suppressed, and the high fitting rigidity of the sealing device can be ensured by the reliable fitting with the double-row inner ring 43 at the fitting portion 54.
Other configurations and effects are the same as those of the sealed roll neck bearing 40 according to the first embodiment, and a description thereof will be omitted.

(Third embodiment)
Next, a sealing device mounted on the hermetic roll neck bearing of the third embodiment will be described with reference to FIG. FIG. 5 is an enlarged cross-sectional view of a main part of a hermetic roll neck bearing equipped with a sealing device according to a third embodiment of the present invention. In this embodiment, only the shape of the fitting portion of the sealing device is different from that of the first embodiment, and other configurations are the same as those of the first embodiment. The description will be simplified or omitted with corresponding reference numerals.

  As shown in FIG. 5, the elastic sealing member 53 of the sealing device 51 of the third embodiment has a tapered fitting portion 54 on its inner peripheral surface and a radial lip portion 55 that protrudes radially inward. With. The fitting portion 54 has an enlarged diameter on the opposite side to the radial lip portion 55 and is formed in a tapered shape having an angle θ. Further, the cored bar 52 extends in the axial direction from the radially inward flange portion 52a, and one end 52b is formed to extend beyond the radial lip portion 55 in the axial direction. That is, the cored bar 52 is formed so as to cover the outer side in the radial direction across the fitting part 54 and the radial lip part 55.

  In such a sealing device 51, the tapered fitting portion 54 is fitted to the outer peripheral surface 43d of one double row inner ring 43, and the radial lip portion 55 is tightened to the outer peripheral surface 44d of the other double row inner ring 44. To be inserted. At this time, due to the elastic deformation of the radial lip portion 55 fitted to the outer peripheral surface 44d of the other double-row inner ring 44, the mounting state of the seal device 51 changes as shown by the broken line in FIG. The substantially entire surface of the fitting portion 54 having a shape comes into contact with the outer peripheral surface 43d of one double row inner ring 43A. Thereby, since the fitting part 54 fits with the outer peripheral surface 43d in a wide area, the sealing device 51 is attached in a state where the attachment rigidity is increased. Moreover, since the fitting part 54 is formed in the taper shape, it can be easily fitted with the double-row inner ring 43, and the assembling performance is excellent.

Accordingly, in the sealed roll neck bearing 40 of the present embodiment, the fitting portion 54 is formed in a tapered shape that expands in the opposite direction to the radial lip portion 55, and one end 52b of the cored bar 52 is radially in the axial direction. Since the lip portion 55 is extended beyond the lip portion 55, the sealing device 51 is attached by the elastic deformation force of the radial lip portion 55 when the radial lip portion 55 is fitted to the outer peripheral surface 44d of the double row inner ring 44. By changing the state, the substantially entire surface of the tapered fitting portion 54 is brought into contact with the outer peripheral surface 43d of the inner ring, whereby high attachment rigidity can be imparted to the seal device 51. Moreover, since the fitting part 54 can be easily fitted to the double-row inner ring 43, the assembling performance is further improved.
Since other operations and effects are the same as those of the sealed roll neck bearing 40 of the first embodiment, description thereof is omitted.

In addition, this invention is not limited to each embodiment and Example mentioned above, A deformation | transformation, improvement, etc. are possible suitably.
For example, the sealing device of the present invention may be arranged around both ends of a plurality of inner rings that are abutted against each other, and may have a configuration in which both shoulder portions that are both ends do not have a stepped shape. The present invention may also be a sealed roll neck bearing provided with cylindrical rollers as rollers.

  In order to confirm the effect of the present invention, two tests were conducted on the sealing performance using the sealing device of the present invention shown in FIGS. 8 (a) and 8 (b) and the conventional sealing device shown in FIG. 8 (c). went.

  6 is a schematic configuration diagram of a sealing performance test apparatus for testing the sealing performance of the sealing apparatus, FIG. 7 is a schematic configuration diagram of a radial runout test apparatus of the sealing apparatus during rotation, and FIGS. 8A to 8C. These are sectional views of each sealing device used in the present sealing performance test. The sealing device of Example 1 shown in FIG. 8A has the same configuration as that described in the first embodiment, and the sealing device of Example 2 shown in FIG. 8B is the second embodiment. It has the same configuration as that described in the form.

  In both the example and the comparative example, the outer peripheral surfaces 43d and 44d of the double-row inner rings 43 and 44 into which the fitting portion 54 and the radial lip portion 55 are fitted have a diameter of 310 mm. In Example 1 shown in FIG. 8A and Example 2 shown in FIG. 8B, the fastening margin of the fitting portion 54 is 0.4 mm, and the fastening margin of the radial lip portion 55 is 0.8 mm. Moreover, the fastening allowance of the fitting part 54 and the radial lip part 55 of the comparative example shown in FIG.8 (c) is both 0.8 mm.

  First, the seal performance test by the seal performance test apparatus 60 shown in FIG. 6 will be described. In the sealing performance test apparatus 60, a first ring 64 and a second ring 65 imitating a pair of inner rings of a hermetic roll neck bearing are provided on the outer peripheral surface of a rotating shaft 63 supported by a support bearing 61 and driven to rotate by a motor 62. However, the end faces are butted together. A seal device 51, which is a test object, is mounted on the outer peripheral surfaces of both end portions 64a and 65a of the first ring 64 and the second ring 65 that face each other. A pair of oil seals 67 are disposed on both sides of the seal device 51 between the first ring 64 and the second ring 65 and the housing 66. A predetermined amount of water supplied from a supply source (pump) 68 passes through a water supply passage 69 provided inside the rotary shaft 62 via a rotary joint, and is directed to the abutting surfaces of both end portions 64a and 65a. To be replenished. Of the replenished water, water that has escaped from the inner peripheral surfaces of the first ring 63 and the second ring 64 is collected by the container 70, and the water that has passed through the sealing device 51 is provided below the housing 66. Collected by the container 71.

  In this seal performance test, in both the example and the comparative example, while the first ring 64 and the second ring 65 are rotated together with the rotating shaft 63 at a predetermined rotation speed (four conditions of 750 rpm, 1000 rpm, 1300 rpm, and 1600 rpm), the supply source After the tap water is intermittently replenished at a rate of 50 cc / min from 68 to both ends 64a and 65a and the test is performed for 5 hours, the amount of water leaked from the sealing device 51 and accumulated in the container 71 is measured to evaluate the sealing performance. Went. Each test was conducted twice, and the test results are shown in Table 1.

  As can be seen from Table 1, in the sealing device of the comparative example, an inflection point is observed in the vicinity of approximately 1300 rpm, and the amount of leakage increases at a higher speed range than that. On the other hand, it can be seen that the sealing device (Examples 1 and 2) 51 of the present invention has an excellent sealing performance with a small amount of water leakage over the entire region from the low speed region to the high speed region.

  Next, in order to verify the above results, a correlation between the rotational speed of the sealing device and radial runout was measured using a radial runout test device 80 shown in FIG. The radial run-out test device 80 has a diameter of 5 m on the outer peripheral side of the cored bar 52 of the sealing device 51 mounted on the outer peripheral surfaces of both ends 64a and 65a of the first ring 64 and the second ring 65 rotating at a predetermined rotational speed. The eddy current sensor 81 was attached, and the radial deflection of the cored bar 52 during rotation was measured. The test results are shown in Table 2.

  As can be seen from Table 2, the run-out in the low speed range is caused by the roundness (accuracy) of the cored bar 52 in both the example and the comparative example, and the change in run-out due to the rotation is in the high speed range of 1300 rpm or more. Seen in In particular, the vibration of the sealing device of the comparative example tends to increase at a rotation speed of 1300 rpm or more, while the increase of the vibration of the sealing device 51 of the first and second embodiments is small, and the sealing by the sealing performance test device 60 It was confirmed that the results agree well with the performance test results.

  The reason for the difference between the test results of the comparative example and the example is that the sealing device of the comparative example is supported by the first ring 64 and the second ring 65 with only two radial lip portions, so that the mounting rigidity is insufficient. However, it is considered that the sealing performance is lowered due to the swinging of the sealing device due to the centrifugal force in the high speed range.

  From the above test results, the sealed-type roll neck bearing of the present invention has a high sealing performance with improved rigidity to be attached to the inner ring even at high speed rotation, following the eccentricity generated between the inner rings abutted against each other. It was confirmed that it could be secured. In addition, this makes it possible to maintain stable performance over a long period of time as a roll neck bearing of a rolling device used under severe conditions.

It is a principal part longitudinal cross-sectional view of the sealed roll neck bearing of 1st Embodiment of this invention. It is the enlarged view (a) of the part enclosed by the circle A in FIG. 1, and the principal part sectional drawing (b) of a sealing device. It is sectional drawing of the state in which the sealing apparatus shown in FIG. 2 was attached. It is a principal part expanded sectional view of the sealing-type roll neck bearing with which the sealing device which is 2nd Embodiment of this invention was mounted | worn. It is a principal part expanded sectional view of the seal-type roll neck bearing with which the sealing device which is 3rd Embodiment of this invention was mounted | worn. It is a schematic block diagram of the sealing performance test apparatus which tests the sealing performance of a sealing apparatus. It is a schematic block diagram of the radial shake amount testing apparatus of the sealing device at the time of rotation. (A)-(c) is sectional drawing of the sealing device used for the comparative test. It is a longitudinal cross-sectional view of the conventional sealed roll neck bearing attached to the roll neck. It is a longitudinal cross-sectional view of the conventional sealing device attached to a pair of inner rings. It is a longitudinal cross-sectional view of the other conventional sealing device attached to a pair of inner ring.

Explanation of symbols

40 Sealed roll neck bearing 41 Outer ring 42 Double row outer ring (outer ring)
43,44 Double-row inner ring (inner ring)
43c, 44c Abutting surfaces 43d, 44d Outer peripheral surface 45 Tapered rollers (rollers)
51 Sealing Device 52 Core Bar 53 Elastic Seal Member 54 Fitting Portion 55 Radial Lip D1 Fitting Port Diameter D2 Radial Lip Port Diameter

Claims (5)

A plurality of outer rings,
Multiple inner rings,
A plurality of rollers disposed between the outer ring and the inner ring;
A sealing device disposed around both ends of the inner ring disposed so as to face each other, and having a metal core and an elastic seal member;
A sealed roll neck bearing comprising:
The inner peripheral surface of the elastic seal member has a fitting portion that fits with one outer peripheral surface of the both end portions, and a radial lip portion that makes sliding contact with the other outer peripheral surface of the both end portions,
The cored bar covers at least the outer side in the radial direction of the fitting portion on the outer peripheral side of the elastic seal member.   The sealed roll neck bearing according to claim 1, wherein an inner diameter of the radial lip portion is smaller than an inner diameter of the fitting portion. The fitting portion is formed in a flat shape having a substantially uniform inner diameter,
3. The sealed roll neck bearing according to claim 1, wherein one end of the cored bar is positioned between the butted surfaces of the both end portions and the radial lip portion in the axial direction. The fitting portion is formed in a curved surface that is substantially symmetrical in the axial direction,
3. The sealed roll neck bearing according to claim 1, wherein one end of the cored bar is positioned between the butted surfaces of the both end portions and the radial lip portion in the axial direction. The fitting portion is formed in a taper shape that expands to the opposite side to the radial lip portion,
The sealed roll neck bearing according to claim 1 or 2, wherein one end of the core bar extends beyond the radial lip portion in the axial direction.

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