JP2007211850A - Constant velocity universal joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To check tilting of ring bodies, even when a load in the opposed direction is applied to the ring body engaging with guide grooves, when an input shaft and an output shaft become eccentric. <P>SOLUTION: This constant velocity universal joint has a torque transmission member 20 displaceably held along a holding window 18 of a retainer 16 interposed between an input shaft side member 12 and an output shaft side member 14 and rollingly contacting with the first guide grooves 32a to 32f and/or the second guide grooves 38a to 38f. The torque transmission member 20 has an annular disk part 21 having an outer peripheral part engaging with the holding window 18, the first ring body 27a and the second ring body 27b rotatably journaled to a first shaft body 23a and a second shaft body 23b via a needle bearing 25. An outer diameter A with the axis of the annular disk part 21 as the center, is set larger than an outer diameter B with the axis of the first ring body 27a and the second ring body 27b as the center (A > B). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to, for example, a constant velocity joint that connects one transmission shaft and the other transmission shaft in a driving force transmission unit of an automobile.

  In a vehicle driven by a motor such as an electric vehicle, an in-wheel motor system in which the motor is built in a wheel is known. In the in-wheel motor system according to this prior art, for example, as shown in Patent Documents 1 to 3, a spindle shaft (a motor unit is connected to a part such as an upright or a knuckle that constitutes an undercarriage part of a vehicle) A motor rotor and a wheel are rotatably provided.

  In general, in a vehicle having a suspension mechanism such as a spring as a suspension structure, when the mass of parts arranged under the spring, such as a wheel, a knuckle, and a suspension arm, so-called unsprung mass increases, In addition, the tire ground contact force greatly fluctuates and so-called road holding performance is deteriorated.

  On the other hand, in a vehicle driven by a motor such as an electric vehicle, when the in-wheel motor system is adopted from the viewpoint of space efficiency and driving force transmission efficiency, the motor stator portion is connected to an upright or a knuckle that is a suspension part. Since the unsprung mass is increased by the weight of the in-wheel motor, the tire contact force fluctuation is increased, and the load holding property is deteriorated.

  In order to solve the above problem, for example, in Patent Document 4, a non-rotating side case of a hollow motor is coupled to a knuckle via a buffer mechanism, and the rotating side case and the wheel of the motor are connected to a flexible cup. An in-wheel motor system configured by coupling with a ring is disclosed.

  As shown in FIG. 22, the flexible coupling 1 in the in-wheel motor system disclosed in Patent Document 4 includes a hollow disk-shaped first to third plates 2 a to 2 c and a central hollow disk-shaped second. On the front and back of the plate 2b, there are linear motion guides 3A and 3B arranged so that their operation directions are orthogonal to each other.

  Specifically, a pair of guide members 4a, 4a attached to the surface of the first plate 2a located on the wheel side opposite to the wheel at an interval of 180 degrees, and the second plate 2b in the middle A hollow disk-shaped first plate 2a and a second plate are attached by a linear motion guide 3A, which is attached to a surface facing the one plate 2a and includes a pair of guide rails 4b and 4b engaged with the pair of guide members 4a and 4a, respectively. The plate 2b is coupled.

  Further, on the back side of the second plate 2b, another pair of guide rails 5b and 5b attached at intervals of 180 degrees in the direction in which the pair of guide rails 4b and 4b are rotated 90 degrees, and the motor side The third plate 2c is attached to the surface facing the second plate 2b, and is formed in a hollow disk shape by a linear motion guide 3B comprising a pair of guide members 5a and 5a engaged with the other pair of guide rails 5b and 5b. The second plate 2b and the third plate 2c are coupled.

  By connecting the first to third plates 2a, 2b, and 2c with the linear motion guides 3A and 3B in this manner, the motor shaft and the wheel shaft are coupled eccentrically in any direction. The torque can be transmitted efficiently.

  However, in the structure in which the rotational driving force of the motor is transmitted toward the wheel side by the flexible coupling disclosed in Patent Document 4, between the first plate 2a and the second plate 2b and between the second plate 2b and the third plate When the motor shaft and the wheel shaft are decentered (displaced) between the plate 2c, torque is transmitted by relative sliding motion (sliding motion) between the pair of guide members and the pair of guide rails. Therefore, there is a problem that the friction loss generated by the slide resistance increases and the surface pressure of the torque transmission surface increases.

  Therefore, the present applicant has proposed a constant velocity joint that can reduce friction loss when the input shaft and the output shaft are decentered and can suppress the surface pressure of the torque transmission surface (Japanese Patent Application 2004). -379609).

Japanese Patent No. 2676025 Japanese National Patent Publication No. 9-506236 Japanese Patent Laid-Open No. 10-305735 Japanese Patent Laid-Open No. 2004-90696

  The present invention has been made in connection with the above proposal, and is a case where a load in the opposite direction is applied to the ring body engaged with the guide groove when the input shaft and the output shaft are eccentric. However, an object of the present invention is to provide a constant velocity joint that can prevent the ring body from tilting and reduce friction loss more suitably.

In order to achieve the above-described object, the present invention provides an input shaft-side member having a plurality of first guide grooves formed on a side surface having a long axis that is equiangularly spaced along the circumferential direction and intersects the diameter;
The side surface opposite to the side surface of the input shaft side member in which the first guide groove is formed has a long axis that is spaced at an equal angle along the circumferential direction and intersects the long axis of the first guide groove at a predetermined crossing angle. An output shaft side member in which a plurality of second guide grooves are formed;
A retainer interposed between a side surface of the input shaft side member in which the first guide groove is formed and a side surface of the output shaft side member in which the second guide groove is formed, and a plurality of holding windows formed;
A torque transmitting member that is held displaceably along the retaining window of the retainer and that is arranged displaceably along the first guide groove and / or the second guide groove to transmit torque;
With
The torque transmission member includes a disc portion in which a first shaft body and a second shaft body are provided coaxially in the center and an outer peripheral portion engages with a holding window of the retainer, and the first shaft body and the second shaft body. A plurality of bearings that respectively surround the peripheral walls of the first and second shaft bodies, which are disposed on both sides of the disk portion, and have the first shaft body and the second shaft body as centers of rotation under the action of the bearings. A first ring body and a second ring body having the same outer diameter that are rotatably mounted on the shaft body and the second shaft body;
The outer diameter of the disc part and the outer diameters of the first ring body and the second ring body are set to be different from each other.

  In this case, the outer peripheral surfaces of the first ring body and the second ring body may be provided with an R surface having a circular arc cross section or a tapered surface that gradually decreases in diameter toward the end side.

  According to the present invention, when the axial centers of the input shaft and the output shaft are displaced from each other and do not coincide with each other, the first ring body and / or in the state in which the engagement state of the disk portion with the holding window of the retainer is maintained. While the second ring is in rolling contact with the side wall of the first guide groove and / or the side wall of the second guide groove, the torque transmitting member is displaced along the first guide groove and / or the second guide groove intersecting each other. Thus, deviation (axial deviation) of the shaft center is allowed.

  In the present invention, when the torque transmission member held by the holding window of the retainer is displaced along the first guide groove and / or the second guide groove, the side wall of the first guide groove and / or the side wall of the second guide groove is provided. On the other hand, the rotational driving force is transmitted from the input shaft side member to the output shaft side member in a state where the first ring body and / or the second ring body is in rolling contact. Therefore, in this invention, compared with the prior art which is a sliding contact, a frictional resistance can reduce and a friction loss can be reduced. As a result, in the present invention, the surface pressure of the torque transmission surface is suppressed as compared with the prior art, and the rotational torque can be transmitted smoothly by reducing the load on the torque transmission member.

  Furthermore, when the shaft centers of the input shaft and the output shaft are each eccentric, loads in opposite directions are applied to one end portion and the other end portion along the axial direction of the torque transmission member, respectively. There is a case where a force to tilt is generated.

  However, in the present invention, the outer diameter A of the annular disk portion constituting the torque transmission member is set larger than the outer diameter B of the first ring body and the second ring body (A> B), or By setting smaller than the outer diameter B of the first ring body and the second ring body (A <B), loads in opposite directions are applied to one end and the other end along the axial direction of the torque transmitting member. Even in this case, the annular disk portion engages with the holding window of the retainer and the torque transmission member is held by the inner wall of the holding window, thereby attempting to tilt the torque transmission member. It is possible to suitably prevent the torque transmission member from overcoming the force and tilting.

  According to the present invention, the following effects can be obtained.

  That is, when the input shaft and the output shaft are eccentric, it is preferable that the ring body is tilted even when a load in the opposite direction is applied to the ring body engaged with the guide groove. Can be blocked.

  Therefore, it is possible to further reduce the friction loss when the input shaft and the output shaft are eccentric, and to suppress the surface pressure of the torque transmission surface. As a result, the heat generation at the sliding portion can be suppressed and the durability can be improved.

  Preferred embodiments of the constant velocity joint according to the present invention will be described below and described in detail with reference to the accompanying drawings.

  1, reference numeral 10 indicates a constant velocity joint according to an embodiment of the present invention. The constant velocity joint 10 includes an input shaft side member 12 connected to one end portion of an input side first shaft (not shown). , An output shaft side member 14 connected to one end of the output-side second shaft (not shown), and a thin disk retainer interposed between the input shaft side member 12 and the output shaft side member 14 16 and a plurality (six in the present embodiment) of torque transmitting members 20 that are movably held along the plurality of holding windows 18 of the retainer 16.

  In this case, the input shaft side member 12 and the output shaft side member 14 are relative, and the output shaft side member 14 is connected to the first shaft on the input side (not shown), while the output side member 14 is not shown. The input shaft side member 12 may be connected to the second shaft. Alternatively, the retainer 16 may be disposed between the input shaft side members 12 and 12, and the retainer 16 may be disposed between the output shaft side members 14 and 14.

  As shown in FIGS. 1 and 2, the input shaft side member 12 includes a shaft portion 22 that is integrally connected to a first shaft on the input side (not shown), and a radius that is continuous with an end portion of the shaft portion 22. It is comprised from the disk part 24 expanded in an outward direction. In addition, you may form in common with the 1st axis | shaft which is not shown in figure by extending the said axial part 22 only predetermined length along an axial direction.

  At the center of a circular flat side surface (a surface orthogonal to the first axis (not shown)) 24 a of the disk portion 24 opposite to the shaft portion 22, the shaft portion 22 is coaxial with the shaft portion 22. A projection 26 having a smaller diameter is bulged, and a male screw 28 is engraved on a part of the outer peripheral surface of the projection 26. The outer diameter of the protrusion 26 is set to be equal to or less than half of the inner diameter of the hole 30 of the output shaft side member 14 through which the protrusion 26 passes (see FIG. 7).

  Further, as shown in FIG. 3, the side surface 24a of the disk portion 24 is formed of a long groove that continues to the outer peripheral edge portion, and has a predetermined angle toward the center in the counterclockwise direction around the point O1 that is the axis. A plurality of (six corresponding to the number of torque transmitting members 20) first guide grooves 32a to 32f are formed to be inclined.

  That is, each of the first guide grooves 32a (32b to 32f) has, on the circular side surface 24a, a portion near the projection 26 between the center O1 and the outer peripheral edge as one end, and the other end is the outer peripheral edge. The six first guide grooves 32a to 32f are each arranged at an interval of 60 degrees around the axis center. In this case, as shown in FIGS. 1 and 2, the plurality of first guide grooves 32a to 32f are cross sections in which the side walls 35a and 35b facing each other with respect to the bottom wall 33 formed of a flat surface are substantially orthogonal to each other. It is formed in a rectangular shape.

  As will be described later, the inclination angle θ1 of the first guide grooves 32a to 32f is set by the intersection angle between the diameter D of the disk portion 24 and the major axis L1 of the first guide grooves 32a to 32f having a substantially elliptical shape. (See FIG. 6). In this case, the tilt angle θ1 may be set in a range of 0 <θ1 <90 degrees, and more preferably, the tilt angle θ1 may be set in a range of 35 <θ1 <45 degrees.

  As shown in FIGS. 1 and 2, the output shaft side member 14 has a hole 30 through which the projection 26 of the input shaft side member 12 penetrates at the center, and the axial direction (input shaft side) on the outer peripheral side. It is comprised by the bottomed cylindrical body in which the recessed part 36 was formed by the annular flange 34 which protrudes only predetermined length along the member 12 direction.

  As shown in FIG. 4, an outer peripheral edge is formed on a circular flat side surface (a surface orthogonal to the second axis not shown) 34a of the output shaft side member 14 facing the side surface 24a of the input shaft side member 12. A plurality of grooves (torque transmission) arranged at a predetermined angle in the clockwise direction opposite to the first guide grooves 32a to 32f with the point O2 being the rotation center as a center. Six second guide grooves 38a to 38f are formed corresponding to the number of members 20.

  Each of the second guide grooves 38a (38b to 38f) has a substantially elliptical shape in which an intermediate portion between the center O2 and the outer peripheral edge portion of the circular side surface 34a is one end portion and the other end portion continues to the outer peripheral edge portion. The six second guide grooves 38a to 38f are arranged around the shaft center at an interval of 60 degrees. In this case, the plurality of second guide grooves 38a to 38f are substantially orthogonal to the side walls 41a and 41b facing each other with respect to the bottom wall 39 formed of a flat surface, as shown in FIGS. The cross section is formed in a rectangular shape.

  The inclination angle θ2 of the second guide grooves 38a to 38f is, as will be described later, the diameter (outer diameter) D of the bottomed cylindrical body and the major axis L2 of the second guide grooves 38a to 38f having a substantially elliptic shape. It is set by the intersection angle (see FIG. 6). In this case, the inclination angle θ2 may be set in a range of 0 <θ2 <90 degrees, and more preferably, the inclination angle θ2 may be set in a range of 35 <θ2 <45 degrees.

  The first guide grooves 32a to 32f formed in the input shaft side member 12 and the second guide grooves 38a to 38f formed in the output shaft side member 14 are arranged line-symmetrically with the diameter (D) as the symmetry axis. The major axes (L1, L2) may be provided so as to be inclined by the same angle (θ1 = θ2) in opposite directions with respect to the diameter (D) (Comparison with FIGS. 3 and 4).

  In this case, the first guide grooves 32a to 32f and the second guide grooves 38a to 38f are opposed to each other with the holding window 18 of the retainer 16 therebetween, and their long axes (L1, L2). And the long axis (L1) of the first guide grooves 32a to 32f and the long axis (L2) of the second guide grooves 38a to 38f do not need to be orthogonal to each other. In other words, the present invention is not limited to providing each guide groove at a position corresponding to each other between the input shaft side member 12 and the output shaft side member 14 which is the counterpart, but the length of each guide groove. What is necessary is just to provide so that an axis | shaft (L1, L2) may cross | intersect.

  In the present embodiment, the radially outer ends of the first guide grooves 32a to 32f and the second guide grooves 38a to 38f are in contact with the outer peripheral edge portions of the input shaft side member 12 and the output shaft side member 14, respectively. However, the present invention is not limited to this, and the terminal ends of the first guide grooves 32a to 32f and the second guide grooves 38a to 38f in the radially outward direction are the input shaft side member 12 and / or It may be provided so as to be separated from the outer peripheral edge of the output shaft side member 14 by a predetermined distance via a clearance. However, in this case, the outer diameters of the input shaft side member 12 and the output shaft side member 14 are increased.

  As shown in FIG. 2, a projection 26 of the input shaft side member 12 that passes through the output shaft side member 14 and protrudes by a predetermined length in a recess 36 of the output shaft side member 14 is screwed into a male screw 28. A slightly thick washer 42 is attached via the nut 40. Between the washer 42 and the output shaft side member 14, a plurality of ball bearings 46 that are rotatably held in the holes of the circular plate 44 are interposed. The plurality of ball bearings 46 are provided for smooth rotation of the output shaft side member 14 and can be omitted.

  As shown in FIG. 5, a ring plate-like retainer 16 is provided between the input shaft side member 12 and the output shaft side member 14, and the retainer 16 has an ellipse corresponding to the number of torque transmission members 20. Six holding windows 18 having a shape are formed. The six holding windows 18 are arranged at intervals of 60 degrees around the axis, and virtual circles connecting the intersections of the major axis and the minor axis of the holding windows 18 are on the same circumference. It is arranged to become.

  The major axis of the holding window 18 formed in an elliptical shape is set so as to intersect with the major axes of the first guide grooves 32a to 32f and the second guide grooves 38a to 38f, respectively.

  Here, the relationship between the intersection angle θ and the inclination angles θ1 and θ2 of the first guide grooves 32a to 32f and the second guide grooves 38a to 38f will be described. FIG. 6 shows a state where the rotation center O1 of the input shaft side member 12, the rotation center O2 of the output shaft side member 14, and the rotation center O3 of the retainer 16 coincide with each other at the point O. Thus, when the rotation center O1 of the input shaft side member 12, the rotation center O2 of the output shaft side member 14, and the rotation center O3 of the retainer 16 coincide with each other at the point O, the first guide of the input shaft side member 12 is obtained. The major axis L1 of the groove 32a (32b to 32f) and the major axis L2 of the second guide groove 38a (38b to 38f) of the output shaft side member 14 intersect with each other at an intersecting angle θ. At that time, by connecting the intersection point of the long axis L1 of the first guide groove 32a (32b to 32f) and the long axis L2 of the second guide groove 38a (38b to 38f) and the diameter D, the crossing angle θ is equal to two. The divided inclination angle θ1 of the first guide groove 32a (32b to 32f) and the inclination angle θ2 of the second guide groove 38a (38b to 38f) are obtained (θ = θ1 + θ2).

  In this case, the crossing angle θ is preferably 0 <θ <180, and more preferably 70 <θ <90 degrees. Also, the inclination angle θ1 of the first guide groove 32a (32b to 32f) and the inclination angle θ2 of the second guide groove 38a (38b to 38f) may be the same (θ1 = θ2), and the inclination angle θ1 is set to be the same. , 0 <θ1 <90 degrees, and more preferably, the inclination angle θ1 is set in a range of 35 <θ1 <45 degrees. Further, the inclination angle θ2 may be set in a range of 0 <θ2 <90 degrees, and more preferably, the inclination angle θ2 may be set in a range of 35 <θ2 <45 degrees.

  If the crossing angle θ between the major axis L1 of the first guide grooves 32a to 32f and the major axis L2 of the second guide grooves 38a to 38f is set too large, the longitudinal direction of the holding window 18 of the retainer 16 is increased. As the outer diameter of the retainer 16 increases, the outer diameter of the input shaft side member 12 and the output shaft side member 14 increases, and the outer diameter of the entire constant velocity joint 10 increases.

  As shown in FIGS. 1, 2, and 10, a plurality (six in this embodiment) of torque transmitting members 20 each have an annular circle whose outer peripheral portion engages with the holding window 18 of the retainer 16. The plate part 21, the cylindrical first shaft body 23a and the second shaft body 23b provided coaxially in the center of the front and back of the annular disk part 21, and the first shaft body 23a and the second shaft body 23b. A plurality of needle bearings (bearings) 25 each surrounding a peripheral wall of the first shaft body, and the first shaft body 23a and the second shaft body 23b with the shaft centers of the first shaft body 23a and the second shaft body 23b as rotation centers. A first ring body 27a and a second ring body 27b which are rotatably attached to the second shaft body 23b and have the same outer diameter.

  As shown in FIG. 10, the outer diameter A centered on the axis of the annular disc portion 21 is the outer diameter (maximum outer diameter) centered on the axes of the first ring body 27a and the second ring body 27b. ) When B is set larger than B (A> B), the input shaft side member 12 and the output shaft side member 14 are deviated (eccentric) and loads in opposite directions are respectively applied. However, it is possible to suitably prevent the torque transmission member 20 from tilting.

  In addition, rolling operation of the plurality of needle bearings 25 is performed between the outer peripheral surfaces of the first shaft body 23a and the second shaft body 23b and the inner peripheral surfaces of the first ring body 27a and the second ring body 27b. Lubricating oil (not shown) for smooth holding may be provided. The needle bearing 25 is provided in a non-contact state with respect to the retainer 16.

  In this case, the first ring body 27a and / or the second ring body 27b of the torque transmission member 20 are the side walls 35a and 35b of the first guide grooves 32a to 32f and / or the side walls 41a of the second guide grooves 38a to 38f, While being in rolling contact with 41b, the first ring body 27a and the second ring body 27b are provided so as to be rotatable in the same direction or in opposite directions under the rolling operation of the needle bearing 25, respectively. In addition, the ridgeline site | part which is a boundary of the end surface of the said 1st ring body 27a and the 2nd ring body 27b and its side surrounding wall is chamfered, and is formed in cross section R shape (refer FIG. 2).

  In other words, the annular disk portion 21 of the torque transmission member 20 is held so as to be displaceable along the holding window 18 of the retainer 16, and to the first shaft body 23 a and the second shaft body 23 b of the torque transmission member 20. The first ring body 27a and / or the second ring body 27b mounted via the needle bearing 25 is provided on the side walls 35a, 35b and / or the output shaft side member 14 of the first guide grooves 32a to 32f of the input shaft side member 12. The side walls 41a and 41b of the second guide grooves 38a to 38f are in rolling contact with the side walls 41a and 41b, respectively, so that they can be displaced. The plurality of torque transmission members 20 are made of, for example, a metal material and perform a rotational torque transmission function.

  The torque transmission member 20 transmits rotational torque from the first shaft (not shown) and the input shaft side member 12 to the second shaft (not shown) via the output shaft side member 14, and the first guide grooves 32a to 32f and / or Alternatively, by displacing along the second guide grooves 38a to 38f, a relative displacement in the radial direction (direction orthogonal to the axial direction) between the input shaft side member 12 and the output shaft side member 14 (first not shown). (Axis misalignment between the axis of the shaft and the axis of the second axis) is enabled.

  Further, the number of the torque transmission members 20 is not limited to six, and there may be a minimum of three torque transmission members 20 as shown in the constant velocity joint 10a according to the modified example of FIG. That's fine. In the constant velocity joint 10a, the number of the first guide grooves 32a to 32c, the second guide grooves 38a to 38c, and the holding window 18 of the retainer 16 corresponds to the number of the three torque transmission members 20. It is formed corresponding to the number of members 20.

  The constant velocity joint 10 according to the present embodiment is basically configured as described above. Next, the operation, action, and effect will be described.

  When a first shaft (not shown) rotates, the rotational torque is transmitted from the input shaft side member 12 to the output shaft side member 14 via each torque transmission member 20, and the second shaft (not shown) is isokinetic with the first shaft. Rotate in a predetermined direction while holding

  FIG. 6 shows a state in which the axis of the first axis coincides with the axis of the second axis, and the deviation amount between the axis of the first axis and the axis of the second axis is zero. That is, in FIG. 6, the rotation center O <b> 1 of the input shaft side member 12, the rotation center O <b> 2 of the output shaft side member 14, and the rotation center O <b> 3 of the retainer 16 are in agreement with each other at point O.

  On the other hand, FIG. 7 shows a state in which the axis of the first axis and the axis of the second axis are displaced in the opposite directions along the horizontal direction. ) A separation distance R along the horizontal direction between the rotation center O1 of 12 and the rotation center O2 of the output shaft side member (second shaft) 14 is a deviation amount (axial deviation amount) of the first shaft and the second shaft. . 6 and 7 are views of the retainer 16 and the output shaft side member 14 as viewed from the front in the direction of arrow Z in FIG. 1, and the first guide grooves 32a to 32f of the input shaft side member 12 are indicated by two-dot chain lines. It is drawn as a virtual line.

  When the axial centers of the first shaft and the second shaft are displaced and do not coincide with each other, the plurality of torques are maintained while maintaining the state where the plurality of torque transmission members 20 are held by the holding windows 18 of the retainer 16. When the transmission member 20 is displaced along the first guide grooves 32a to 32f and the second guide grooves 38a to 38f intersecting with each other, a deviation (axial deviation) of the shaft center is allowed.

  Therefore, in the present embodiment, while being held by the holding window 18 of the retainer 16, the torque transmission member 20 is rotationally driven while being displaced between the first guide grooves 32a to 32f and the second guide grooves 38a to 38f. Force is transmitted from the input shaft side member 12 to the output shaft side member 14, but against the side walls 35a and 35b of the first guide grooves 32a to 32f and / or the side walls 41a and 41b of the second guide grooves 38a to 38f. The torque transmission member 20 is displaced along the first guide grooves 32a to 32f and / or the second guide grooves 38a to 38f in a state where the first ring body 27a and / or the second ring body 27b are in rolling contact. Therefore, frictional resistance can be reduced and friction loss can be reduced.

  In other words, in the prior art, the sliding resistance is large due to the sliding contact between the guide member constituting the flexible coupling (linear guide) and the guide rail, whereas in the present embodiment, the first shaft body 23a of the torque transmission member 20 is used. In addition, since the rolling friction is caused by the rolling contact between the first ring body 27a and the second ring body 27b that are pivotally supported by the second shaft body 23b via the needle bearing 25, the friction resistance is reduced as compared with the prior art. Can do. As a result, in the present embodiment, the constant pressure joint 10 that smoothly transmits the rotational torque is obtained by reducing the load on the torque transmission member 20 by reducing the surface pressure of the torque transmission surface as compared with the prior art. be able to.

  Here, the torque transmission member 20 when the input shaft side member 12, the output shaft side member 14, and the retainer 16 are integrally rotated in the direction of the arrow A in a state where the first shaft and the second shaft (not shown) are misaligned. The positional relationship among the first guide groove 32a, the second guide groove 38a, and the holding window 18 will be described in detail with reference to FIGS.

  8 and 9, the other five torque transmission members 20 are omitted, and a single holding window 18 that engages with one torque transmission member 20 and a single sliding window on which the one torque transmission member 20 slides. This is shown for convenience, focusing on the positional relationship between the first guide groove 32a and the second guide groove 38a. That is, the state in which the input shaft side member 12 and the output shaft side member 14 rotate once in the direction of the arrow A is divided into the order of (1) to (12), and only the odd numbered state is circular as a whole in FIG. 9 are arranged in parallel (parallel), and only the even-numbered states are arranged cyclically (in parallel) in FIG. 9 as a whole.

  8 and 9, the input shaft side member 12 and the first guide groove 32a are each indicated by a two-dot chain line, the output shaft side member 14 and the second guide groove 38a are respectively indicated by a broken line, the retainer 16 and the torque transmission. The member 20 and the holding window 18 are indicated by solid lines.

  In this case, the input shaft side member 12 rotates about the displaced rotation center O1, the output shaft side member 14 rotates about the displaced rotation center O2, and the retainer 16 rotates the displaced rotation center O2. Rotate around O3. A triangle is formed by connecting the rotation center O1, the rotation center O2, and the rotation center O3.

  In the following description, the inner sides of the first guide groove 32a and the second guide groove 38a formed in a substantially oval shape that are close to the rotation centers O1 and O2, respectively, are referred to as “one end along the major axis direction”. The outer peripheral edge side in the opposite direction is defined as “the other end along the long axis direction”. Further, in the elliptical shape of the holding window 18 formed in the retainer 16, the end on the rotation direction side is defined as “one end along the long axis direction”, and the end opposite to the rotation direction is defined as “long axis direction”. The other end along. "

  First, in the state of (1) of FIG. 8, the torque transmission member 20 is located in the center part of the elliptical holding window 18 of the retainer 16, and when rotated by a predetermined angle from the state of (1) of FIG. In the state (2), the torque transmission member 20 is held at the other end portion (outer peripheral edge side) along the long axis direction of the first guide groove 32a, and the long guide direction of the second guide groove 38a. Is slightly displaced along one end portion side (opposite to the outer peripheral edge portion), and slightly displaced from the central portion of the elliptical holding window 18 toward one end portion in the major axis direction.

  When rotating by a predetermined angle from the state of (2) of FIG. 9, the state of (3) of FIG. The second guide groove 38a is further displaced toward one end portion along the long axis direction and reaches the one end portion on the long axis side of the elliptical holding window 18.

  When a predetermined angle is rotated from the state of (3) of FIG. 8, the state of FIG. 9 (4) is obtained, and the torque transmitting member 20 is held at one end in the major axis direction of the elliptical holding window 18. The first guide groove 32a is slightly displaced toward one end portion along the major axis direction, and further displaced toward one end portion along the major axis direction of the second guide groove 38a.

  When rotating by a predetermined angle from the state of (4) in FIG. 9, the state of FIG. 8 (5) is obtained, and the torque transmission member 20 is held at one end in the major axis direction of the elliptical holding window 18. The first guide groove 32a is further displaced toward one end portion along the long axis direction and reaches the one end portion along the long axis direction of the second guide groove 38a.

  When a predetermined angle is rotated from the state of (5) of FIG. 8, the state of (6) of FIG. 9 is obtained, and the torque transmitting member 20 is held at one end in the major axis direction of the second guide groove 38a. The first guide groove 32a is slightly displaced toward one end portion along the major axis direction, and is slightly displaced from one end portion in the major axis direction of the holding window 18 in the opposite direction (direction away from the one end portion). .

  When a predetermined angle is rotated from the state of (6) of FIG. 9, the state of (7) of FIG. 8 is obtained, and the torque transmission member 20 is held at one end in the major axis direction of the second guide groove 38a. The first guide groove 32a is displaced to one end portion in the major axis direction and is also displaced to the center portion of the holding window 18 formed in an elliptical shape.

  When rotating by a predetermined angle from the state of (7) of FIG. 8, the state of (8) of FIG. 9 is obtained, and the torque transmission member 20 is held at one end in the major axis direction of the first guide groove 32a. 2 A slight displacement toward the outer peripheral edge side along the guide groove 38a and a displacement from the central portion of the holding window 18 formed in an elliptical shape toward the other end portion in the major axis direction.

  When a predetermined angle is rotated from the state of FIG. 9 (8), the state of FIG. 8 (9) is obtained, and the torque transmission member 20 is held at one end in the major axis direction of the first guide groove 32a. 2 Further displacement is made toward the outer peripheral edge side along the guide groove 38a, and the other end portion in the major axis direction of the holding window 18 formed in an elliptical shape is reached.

  When a predetermined angle is rotated from the state of (9) of FIG. 8, the state of (10) of FIG. 9 is obtained, and the torque transmission member 20 is held at the other end in the major axis direction of the holding window 18 formed in an elliptical shape. As it is, the first guide groove 32a is slightly displaced in the opposite direction away from one end portion in the major axis direction, and further displaced toward the outer peripheral edge side along the second guide groove 38a.

  When rotating by a predetermined angle from the state of (10) of FIG. 9, the state of (11) of FIG. 8 is obtained, and the torque transmission member 20 is held at the other end in the major axis direction of the holding window 18 formed in an elliptical shape. As it is, the first guide groove 32a is slightly displaced from the one end of the first guide groove 32a toward the outer peripheral edge, and the other end along the major axis of the second guide groove 38a (outer peripheral edge). To reach.

  When rotating by a predetermined angle from the state of (11) of FIG. 8, the state of (12) of FIG. 9 is obtained, and the torque transmitting member 20 is connected to the other end portion (outer peripheral edge portion) along the major axis direction of the second guide groove 38a. The other end of the holding window 18 formed in an elliptical shape while being slightly displaced toward the outer peripheral edge, which is the other end along the longitudinal direction of the first guide groove 32a. It is slightly displaced in the direction away from the part.

  9 is rotated by a predetermined angle from the state shown in FIG. 9 (12), the original state shown in FIG. 8 (1) is restored, and the torque transmitting member 20 is connected to the other end of the second guide groove 38a along the long axis direction. While being held at the (outer peripheral edge side), it reaches the other end (outer peripheral edge side) along the major axis direction of the first guide groove 32a, and the central portion of the holding window 18 formed in an elliptical shape Displace to the position of. Hereinafter, the states (1) to (12) are infinitely circulated.

  Therefore, as shown in the states (1) to (12) of FIGS. 8 and 9, the torque transmission member 20 held by the elliptical holding window 18 of the retainer 16, and the first torque transmission member 20 The input shaft side in a state in which the axial displacement of the first shaft and the second shaft is allowed based on the cooperative action of the first guide groove 32a and the second guide groove 38a with which the ring body 27a and the second ring body 27b are in rolling contact. The member 12 and the output shaft side member 14 rotate integrally, and the rotational torque is smoothly transmitted from the input side to the output side.

  As described above, the first shaft and the second shaft are maintained while maintaining the constant velocity between the first shaft (not shown) connected to the input shaft side member 12 and the second shaft connected to the output shaft side member 14. A misalignment is preferably tolerated.

  When the axis (rotation center O1) of the input shaft side member 12 and the axis (rotation center O2) of the output shaft side member 14 are eccentric, the axis of the torque transmission member 20 is shown in FIG. Loads in directions opposite to each other at one end and the other end along the direction, for example, loads in the directions of the arrows X1 and X2 are applied to the torque transmission member 20, as indicated by a one-dot chain line in FIG. In some cases, a force for tilting the torque transmission member 20 is generated.

  However, in the present embodiment, the outer diameter A of the annular disk portion 21 constituting the torque transmission member 20 is set larger than the outer diameter B of the first ring body 27a and the second ring body 27b (A > B) Even when a load in a direction opposite to each other is applied to one end and the other end of the torque transmission member 20 along the axial direction, the annular disk portion 21 is held by the holding window 18 of the retainer 16. And the torque transmission member 20 is held by the inner wall of the holding window 18 so that the torque transmission member 20 can be tilted overcoming the force to tilt the torque transmission member 20. Can be prevented.

  In the present embodiment, when the outer diameter A of the annular disk portion 21 constituting the torque transmission member 20 is set larger than the outer diameter B of the first ring body 27a and the second ring body 27b (A > B) is described as an example, but is not limited thereto.

  For example, as shown in FIG. 12, in the torque transmission member 20a according to the first modification, the outer diameter A of the annular disc portion 21a is the outer diameter (maximum outer diameter) of the first ring body 27a and the second ring body 27b. Diameter) is set smaller than B (A <B). The shape of the holding window 18 of the retainer 16 with which the annular disc portion 21a engages is also set corresponding to the outer diameter of the annular disc portion 21a.

  In this case, similarly to the above, even when the loads (X1, X2) in opposite directions are applied to the one end and the other end along the axial direction of the torque transmission member 20a, the annular disk The portion 21a engages with the holding window 18 of the retainer 16, and the torque transmission member 20 is held by the inner wall of the holding window 18, thereby overcoming the force to tilt the torque transmission member 20a. It is possible to suitably prevent the member 20a from tilting.

  Further, as shown in FIG. 13, in the torque transmission member 20b according to the second modification, the outer diameter A of the annular disc portion 21 is made larger than the maximum outer diameter B of the first ring body 27a and the second ring body 27b. Is set larger (A> B), and the outer circumferential surfaces substantially parallel to the axes of the first ring body 27a and the second ring body 27b are formed of a predetermined radius of curvature and extend in a cross-section arc shape along the axial direction. It may be set as the R plane 50.

  The outer peripheral surfaces of the first ring body 27a and the second ring body 27b are R surfaces 50 each having an arcuate cross section, thereby engaging the first guide grooves 32a to 32f and the second guide grooves 38a to 38f, respectively. The load (edge load) applied to the edge portion can be reduced by suppressing the surface pressure on the edge portion of the first ring body 27a and the second ring body 27b.

  Furthermore, as shown in FIG. 14, in the torque transmission member 20c according to the third modification, the outer diameter A of the annular disk portion 21 is made larger than the maximum outer diameter B of the first ring body 27a and the second ring body 27b. Is set larger (A> B), and the outer peripheral surfaces of the first ring body 27a and the second ring body 27b are preferably set to a tapered surface 52 that gradually decreases in diameter toward the end side along the axial direction.

  The tapered surface 52 formed on the outer peripheral surface of the first ring body 27a or the second ring body 27b and the wall surfaces of the first guide grooves 32a to 32f or the second guide grooves 38a to 38f are engaged with each other, so that the first The first ring body 27a or the second ring body 27b is applied with a force that rolls in an arc instead of a straight line, and the surface pressure against the edge portions of the first ring body 27a and the second ring body 27b is suppressed, and the edge The load (edge load) applied to the portion can be reduced.

  Furthermore, as shown in FIG. 15, in the torque transmission member 20d according to the fourth modification, the outer diameter A of the annular disc portion 21a is larger than the maximum outer diameter B of the first ring body 27a and the second ring body 27b. May be set smaller (A <B), and the outer peripheral surfaces of the first ring body 27a and the second ring body 27b may be set as the R-surface 50 having a circular arc shape having a predetermined radius of curvature. The operational effect of the R surface 50 is the same as described above.

  Furthermore, as shown in FIG. 16, in the torque transmission member 20e according to the fifth modification, the outer diameter A of the annular disc portion 21a is larger than the maximum outer diameter B of the first ring body 27a and the second ring body 27b. May be set to be small (A <B), and the outer peripheral surfaces of the first ring body 27a and the second ring body 27b may be set to a tapered surface 52 that gradually decreases in diameter toward the end side along the axial direction. The operational effect of the tapered surface 52 is the same as described above.

  Next, the constant velocity property of the constant velocity joint 10 according to the present embodiment will be described based on FIG.

  In FIG. 17, a distance between the center point O4 of the torque transmission member 20 and the rotation center O3 of the retainer 16 is a, and the center point O4 of the torque transmission member 20 and the rotation center O1 of the input shaft side member 12 are connected. The distance is Cin, and the distance connecting the center point O4 of the torque transmission member 20 and the rotation center O2 of the output shaft side member 14 is Cout. The center point O4 of the torque transmission member 20 indicates the center of gravity of the torque transmission member 20 formed of a cylindrical body.

  Also, Vin is the linear velocity (tangential velocity vector) of the input shaft side member 12 at the center point O4 of the torque transmission member 20, and linear velocity (tangential velocity vector) of the output shaft side member 14 at the center point O4 of the torque transmission member 20 is. Is Vout, and the linear velocity (tangential velocity vector) of the retainer 16 at the center point O4 of the torque transmitting member 20 is Vret.

  Further, the angular velocity of the input shaft side member 12 is ω1 (input shaft angular velocity), and the angular velocity of the output shaft side member 14 is ω2 (output shaft angular velocity).

In this case, when the angular velocity ω1 of the input shaft side member 12 is separated into the radius (Cin) and the linear velocity (Vin),
ω1 = Vin / Cin (1)
It is expressed.

Next, the following equations are derived from the respective linear speed ratios (tangential speed ratios) at the center point O4 of the torque transmitting member 20.
Vin / Vret = Cin / a (2)
Vout / Vret = Cout / a (3)
Therefore, Vin / Vout = Cin / Cout is established from the equations (2) and (3). If this equation is transformed,
Vin = (Cin / Cout) · Vout (4)
It becomes. Substituting the above equation (4) into the above equation (1),
ω1 = (1 / Cin) · (Cin / Cout) · Vout
= Vout / Cout
= Ω2
Thus, the relationship between the input shaft angular velocity ω1 and the output side angular velocity ω2 is ω1 = ω2, and constant velocity between the input shaft and the output shaft is ensured.

  By the way, in the flexible coupling which concerns on the comparative example disclosed by patent document 1, as FIG.20 and FIG.21 shows, the shaft center (rotation center) E of the input shaft side plate and the shaft center F of the output shaft side plate are shown. And the center K of a circle H connecting the intersections of the four linear motion guides (intersections G1 to G4 between the guide member and the guide rail), the locus of the center K becomes a circle L. The circle L is a circle whose diameter is the axis E and the axis F.

  In the flexible coupling according to this comparative example, when the shaft center E of the input shaft side plate and the shaft center F of the output shaft side plate are deviated (off-axis misalignment) and rotated in the arrow direction by an angle α, The center K of the circle H connecting the intersections of the four linear motion guides and the circle L that is the locus of the center K rotate (revolution) at an angular velocity of 2α in the direction opposite to the rotation direction of the input shaft side plate and the output shaft side plate. ) To ensure constant velocity.

  Therefore, in the comparative example, when the input shaft side plate and the output shaft side plate make one rotation (360 degrees) with the shaft center E and the shaft center F as the center of rotation, the one arranged at the intersection of the linear guides makes two rotations. (720 degrees), there is a problem that vibration is generated from the one arranged at the intersection of the linear motion guides.

  On the other hand, in this embodiment, since the occurrence of vibration as in the comparative example is prevented, there is an advantage that the rotational torque can be transmitted smoothly.

  Next, a constant velocity joint 100 according to another embodiment of the present invention is shown in FIG.

  In the constant velocity joint 100 according to another embodiment, an annular crimping portion 102 bent in an L-shaped cross section is formed on the input shaft side member 12a, and the input shaft side member 12a is connected to the output shaft side by the crimping portion 102. This is different from the above embodiment in that it is connected to the member 14a.

  The output shaft side member 14a is provided with a plurality of ball bearings 104 in which an annular groove is formed at a portion engaging with the caulking portion 102, and is rotatably accommodated in the annular groove.

  Since other configurations and operational effects are the same as those of the above-described embodiment, detailed description thereof is omitted.

It is a principal part disassembled perspective view of the constant velocity joint which concerns on embodiment of this invention. It is a longitudinal cross-sectional view along the axial direction of the constant velocity joint shown in FIG. It is the side view seen from the arrow Z direction of the input-shaft side member which comprises the constant velocity joint shown in FIG. It is the side view seen from the arrow Z direction of the output-shaft side member which comprises the constant velocity joint shown in FIG. It is the side view seen from the arrow Z direction of the retainer and torque transmission member which comprise the constant velocity joint shown in FIG. FIG. 3 is a side view showing a state in which the axis of the first shaft on the input side and the axis of the second shaft on the output side coincide with each other in the constant velocity joint shown in FIG. 1. FIG. 6 is a side view showing a state in which the axis of the first axis and the axis of the second axis are displaced by a separation distance R along the horizontal direction from the state shown in FIG. 5. It is operation | movement explanatory drawing which shows the relative relationship between the torque transmission member hold | maintained at the holding | maintenance window, and the 1st guide groove and the 2nd guide groove for convenience. It is operation | movement explanatory drawing which shows the relative relationship between the torque transmission member hold | maintained at the holding | maintenance window, and the 1st guide groove and the 2nd guide groove for convenience. It is a longitudinal cross-sectional view along the axial direction of the said torque transmission member. It is operation | movement explanatory drawing which shows the state to which the load of the direction opposite to the said torque transmission member was provided. It is a longitudinal cross-sectional view along the axial direction of the torque transmission member which concerns on a 1st modification. It is a longitudinal cross-sectional view along the axial direction of the torque transmission member which concerns on a 2nd modification. It is a longitudinal cross-sectional view along the axial direction of the torque transmission member which concerns on a 3rd modification. It is a longitudinal cross-sectional view along the axial direction of the torque transmission member which concerns on a 4th modification. It is a longitudinal cross-sectional view along the axial direction of the torque transmission member which concerns on a 5th modification. It is a figure with which it uses for description of the constant velocity of the constant velocity joint shown in FIG. It is a principal part disassembled perspective view which shows the modification of the constant velocity joint shown in FIG. It is a longitudinal cross-sectional view along the axial direction of the constant velocity joint which concerns on other embodiment of this invention. It is a figure used for operation | movement of the flexible coupling which concerns on a comparative example. It is the elements on larger scale of FIG. It is a disassembled perspective view of the flexible coupling which concerns on a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 10a, 100 ... Constant velocity joint 12, 12a ... Input shaft side member 14, 14a ... Output shaft side member 16 ... Retainer 18 ... Holding window 20, 20a-20e ... Torque transmission member 21, 21a ... Annular disk part 22 ... Shaft portions 23a, 23b ... Shaft body 24 ... Disk portion 25 ... Needle bearings 27a, 27b ... Ring body 30 ... Hole portions 32a-32f ... First guide groove 34 ... Annular flange 36 ... Recesses 38a-38f ... Second guide groove 40 ... Nut 42 ... Washer 44 ... Plate 46, 104 ... Ball bearing 50 ... R surface 52 ... Taper surface 102 ... Caulking portion

Claims (3)

An input shaft side member having a plurality of first guide grooves formed on a side surface having a long axis that is equiangularly spaced along the circumferential direction and intersects the diameter;
The side surface opposite to the side surface of the input shaft side member in which the first guide groove is formed has a long axis that is spaced at an equal angle along the circumferential direction and intersects the long axis of the first guide groove at a predetermined crossing angle. An output shaft side member in which a plurality of second guide grooves are formed;
A retainer interposed between a side surface of the input shaft side member in which the first guide groove is formed and a side surface of the output shaft side member in which the second guide groove is formed, and a plurality of holding windows formed;
A torque transmitting member that is held displaceably along the retaining window of the retainer and that is arranged displaceably along the first guide groove and / or the second guide groove to transmit torque;
With
The torque transmission member includes a disc portion in which a first shaft body and a second shaft body are provided coaxially in the center and an outer peripheral portion engages with a holding window of the retainer, and the first shaft body and the second shaft body. A plurality of bearings that respectively surround the peripheral walls of the first and second shaft bodies, which are disposed on both sides of the disk portion, and have the first shaft body and the second shaft body as centers of rotation under the action of the bearings. A first ring body and a second ring body having the same outer diameter that are rotatably mounted on the shaft body and the second shaft body;
The constant velocity joint, wherein the outer diameter of the disc portion and the outer diameters of the first ring body and the second ring body are set to be different from each other. The constant velocity joint according to claim 1,
A constant velocity joint, wherein an outer peripheral surface of each of the first ring body and the second ring body is provided with an R surface having an arcuate cross section. The constant velocity joint according to claim 1,
The constant velocity joint according to claim 1, wherein a tapered surface that gradually decreases in diameter toward an end side is provided on outer peripheral surfaces of the first ring body and the second ring body.

Images