JP2009127637A - Constant velocity universal joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate reduction of the number of parts and improvement of assembling work efficiency, in a nonslip structure of a shaft from an inner ring. <P>SOLUTION: This constant velocity universal joint is equipped with an outer ring and an inner ring 20 for transmitting torque while allowing angular displacement between itself and the outer ring, and has a nonslip structure of the shaft 60 from the inner ring 20 by inserting and fitting the shaft 60 in a shaft hole 26 of the inner ring 20 and fitting a stopper ring 70 in a diametrical reduced state in an annular groove 62 formed on the outer peripheral face of the shaft 60. A bottom face 64 of the annular groove 62 of the shaft 60 is gradually reduced in diameter from a shaft axial end side to the inner ring side, and a shaft axial cross section is formed as a linear tapered face. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fixed or sliding constant velocity universal joint that is used in a power transmission system of an automobile or various industrial machines, and is incorporated in, for example, a drive shaft or a propeller shaft of an automobile. The present invention relates to a fitting structure between a joint member and a shaft.

  For example, a sliding type constant velocity universal joint (double offset type constant velocity universal joint: DOJ) used as a coupling joint for an automobile drive shaft or the like has a plurality of linear shapes parallel to the axis as shown in FIG. An outer ring 110 in which track grooves 112 are formed on the cylindrical inner peripheral surface 114 at equal intervals in the circumferential direction, and a plurality of linear track grooves 122 parallel to the axis corresponding to the track grooves 112 of the outer ring 110 are formed in a spherical outer periphery. A plurality of inner rings 120 formed on the surface 124 at equal intervals in the circumferential direction, a track groove 112 of the outer ring 110 and a track groove 122 of the inner ring 120 are arranged in cooperation to transmit torque. A ball 130 and a cage 140 that holds the ball 130 interposed between a cylindrical inner peripheral surface 114 of the outer ring 110 and a spherical outer peripheral surface 124 of the inner ring 120 are provided. Each ball 130 is accommodated in each of a plurality of pockets 142 formed in the cage 140 and arranged at equal intervals in the circumferential direction.

  When this constant velocity universal joint is used for a drive shaft, a shaft portion 116 that extends integrally from one end of the outer ring 110 in the axial direction is connected to the differential, and a shaft 160 that is spline-fitted into the shaft hole 126 of the inner ring 120 is provided. It is connected to a fixed constant velocity universal joint.

  If the outer ring 110 and the inner ring 120 are angularly displaced between the shaft portion 116 of the outer ring 110 and the shaft 160 on the inner ring 120 side, the ball 130 accommodated in the pocket 142 of the cage 140 is always at any operating angle. The operating angle is maintained in the bisection plane, and the constant velocity of the joint is ensured.

  A structure in which the shaft end of the shaft 160 is inserted into the shaft hole 126 of the inner ring 120 is adopted as a connection structure between the inner ring 120 and the shaft 160 of the sliding type constant velocity universal joint. A female spline 128 is formed on the inner peripheral surface of the shaft hole 126 of the inner ring 120 as irregularities along the axial direction, and a male spline 168 is also formed on the outer peripheral surface of the shaft end of the shaft 160. By inserting the shaft end of the shaft 160 into the shaft hole 126 of the inner ring 120 and engaging the male spline 168 and the female spline 128, the shaft 160 is fitted to the inner ring 120 so that torque can be transmitted between the two (for example, , See FIG. 1 of Patent Document 1).

  In general, in the fitting structure of the inner ring 120 of the constant velocity universal joint and the shaft 160, an annular groove is formed on the outer peripheral surface of the shaft 160, and a retaining ring is fitted into the annular groove so that the inner ring 120 has a rear end surface. By making contact, the shaft 160 is prevented from coming off from the inner ring 120.

  In this case, if a variation occurs in the axial width of the inner ring 120 and the position of the annular groove of the shaft 160 due to a manufacturing error or the like, an axial gap is generated between the retaining ring and the inner ring 120. As a result, the inner ring 120 is moved to the shaft 160. On the other hand, there is a problem that it moves in the axial direction and comes into contact with the retaining ring, causing vibration and noise.

  In order to solve this problem, the fitting structure of the inner ring 120 and the shaft 160 disclosed in Patent Document 1 includes an annular groove 162 formed on the outer peripheral surface of the shaft 160 and an annular groove 162 as shown in FIG. A first retaining ring 170 that is fitted and abuts on the back end surface 121 of the inner ring 120, and a second retaining ring 180 that is fitted in the annular groove 162 and abuts on the end surface 164 of the annular groove 162. The end faces 172 and 182 that are configured and the first retaining ring 170 and the second retaining ring 180 are opposed to each other are tapered.

  When the second retaining ring 180 is contracted in the radial direction, the end surface 174 of the first retaining ring 170 has a taper action at the end surfaces 172 and 182 where the first retaining ring 170 and the second retaining ring 180 are in contact. The second retaining ring 180 moves axially to a position where the end face 184 abuts against the end face 164 of the annular groove 162.

In this way, the inner ring 120 is restrained with no gap in the axial direction with respect to the shaft 160. Accordingly, vibration and noise generated by the inner ring 120 moving in the axial direction with respect to the shaft 160 and coming into contact with the retaining rings 170 and 180 are prevented in advance (for example, second in Patent Document 1). (See figure).
JP-A-3-89026

  By the way, in the fitting structure of the inner ring 120 and the shaft 160 disclosed in Patent Document 1 described above, the taper action at the end faces 172 and 182 where the first retaining ring 170 and the second retaining ring 180 contact each other causes the first The retaining ring 170 moves axially to a position where its end surface 174 abuts on the back end surface 121 of the inner ring 120, and the second retaining ring 180 axially travels to a position where its end surface 184 contacts the end surface 164 of the annular groove 162. Moving.

  As a result, the inner ring 120 is restrained in the axial direction with respect to the shaft 160 without any gap, so that vibration and noise generated by the inner ring 120 moving in the axial direction with respect to the shaft 160 and abutting against the retaining rings 170 and 180 are generated. This is an effective means in that it can be prevented.

  However, since the retaining ring of the first retaining ring 170 and the second retaining ring 180 is combined with the retaining ring of the shaft 160 with respect to the inner ring 120, the number of parts as a retaining means for the shaft 160 increases. To do.

  In addition, since the number of parts is large and the end faces 172 and 182 where the first retaining ring 170 and the second retaining ring 180 face each other are in contact with each other, the first retaining ring 170 is tapered. The operation of combining the second retaining ring 180 and the shaft 160 is complicated and it is difficult to improve the assembly workability.

  Therefore, the present invention has been proposed in view of the above-mentioned problems, and the object of the present invention is to easily reduce the number of parts and improve the assembly workability in the shaft retaining structure for the inner ring. It is to provide a quick universal joint.

  As a technical means for achieving the above-described object, the present invention provides a constant velocity universal including an outer joint member and an inner joint member that transmits torque while allowing angular displacement between the outer joint member and the outer joint member. A joint is inserted into the shaft hole of the inner joint member and fitted, and a retaining ring is fitted in an annular groove formed on the outer peripheral surface of the shaft in a reduced diameter state, and the shaft is fitted to the inner joint member. The annular groove of the shaft has a reduced diameter surface that gradually decreases in diameter from the shaft shaft end side toward the inner joint member side.

  Assembly of the shaft to the inner joint member is performed in the following manner. First, the shaft is inserted and fitted from the inlet side opening end of the shaft hole of the inner joint member. The shaft is inserted to a position where an annular groove formed in the outer peripheral surface protrudes from the inner opening end of the inner joint member. In this state, the retaining ring is fitted into the annular groove of the shaft in a state where the diameter of the retaining ring is larger than that in the natural state. The retaining ring fitted in the annular groove is in a reduced diameter state in which the diameter is reduced radially inward by an elastic restoring force to a natural state.

  In the present invention, since the annular groove of the shaft has a bottom surface that is a diameter-reducing surface that gradually decreases from the shaft shaft end side toward the inner joint member side, the following effects (1) and (2) are obtained. Present.

  (1) When the retaining ring is fitted into the annular groove of the shaft, the retaining ring is subjected to a force that reduces the diameter inward in the radial direction with an elastic restoring force to a natural state. At this time, the inner diameter of the retaining ring is in contact with the bottom surface of the annular groove. In the present invention, the bottom surface of the annular groove of the shaft is a reduced diameter surface that gradually decreases from the shaft shaft end side toward the inner joint member side, so that the diameter reduction force of the retaining ring generates an axial component force. Then, the retaining ring moves to the inlet side of the inner joint member by this axial component force, and comes into contact with the inner end face of the inner joint member. As a result, the inner joint member is restrained without a gap in the axial direction with respect to the shaft. That is, the inner joint member is held between the shaft shoulder portion and the retaining ring without any difficulty.

  (2) When the retaining ring is fitted into the annular groove of the shaft, the retaining ring is subjected to a force that reduces its diameter radially inward with an elastic restoring force to a natural state. In the present invention, the bottom surface of the annular groove of the shaft is a reduced diameter surface that gradually decreases from the shaft shaft end side toward the inner joint member side, so that a part of the inner diameter of the retaining ring comes into contact with the bottom surface of the annular groove. The other part of the inner diameter of the retaining ring is not in contact with the bottom surface of the annular groove. The other part of the inner diameter of the retaining ring that is not in contact with the bottom surface of the annular groove is reduced in diameter so as to come into contact with the bottom surface of the annular groove with the above-mentioned reduction force. The outer diameter side end surface of the retaining ring is in contact with the inner side end surface of the inner joint member. As a result, the inner joint member is restrained without a gap in the axial direction with respect to the shaft. That is, the inner joint member is held between the shaft shoulder portion and the retaining ring without any difficulty.

  In the present invention, the inner joint member is restrained with respect to the shaft without any gap in the axial direction by the retaining ring by the action of at least one of (1) and (2). Which of these actions (1) and (2) exhibits depends on the material and shape of the retaining ring or the shape of the annular groove.

  The annular groove of the shaft in the present invention preferably has a structure including an end surface that is formed continuously from the bottom surface, which is a reduced diameter surface, toward the shaft shaft end side and rises in a direction orthogonal to the shaft axis direction. In this way, even when a large pulling force is applied to the shaft, the retaining ring is in contact with and locked to the inner end surface of the annular groove, so that the shaft is firmly prevented from coming off the inner joint member. It becomes. In addition, the back side end surface of the inner joint member means an end surface opposite to the inlet side end surface located on the side where the shaft is inserted with respect to the shaft hole of the inner joint member.

  In the present invention, the bottom surface of the annular groove of the shaft has a tapered surface that is linearly reduced in the cross section in the axial direction of the shaft, or a curved line in the cross section in the axial direction of the shaft. A curved surface is possible. The curved surface may be a convex curved surface or a concave curved surface.

  On the other hand, it is desirable that the inner diameter of the retaining ring in the present invention has a shape that is gradually expanded from the inner joint member side to the shaft shaft end side, that is, from the inlet side to the inner side of the inner joint member. In this way, the inner diameter of the retaining ring does not come into contact with the bottom surface of the annular groove at the edge. Therefore, in the above-described action (1), the retaining ring is smoothly moved to the inlet side of the inner joint member by the axial component force. It becomes easy to make. As a result, the inner joint member is more reliably restrained in the axial direction with respect to the shaft without a gap. That is, the inner joint member is held between the shaft shoulder portion and the retaining ring without any difficulty.

  On the contrary, the inner diameter of the retaining ring in the present invention can be a shape gradually reduced in diameter from the inner joint member side to the shaft shaft end side, that is, from the inlet side to the inner side of the inner joint member. . In this way, in the above-mentioned action (2), the other part of the inner diameter of the retaining ring that is not in contact with the bottom surface of the annular groove exerts a large force to reduce the diameter so as to contact the bottom surface of the annular groove. Therefore, the entire retaining ring is easily inclined toward the inlet side of the inner joint member. As a result, the inner joint member is more reliably restrained in the axial direction with respect to the shaft without a gap. That is, the inner joint member is held between the shaft shoulder portion and the retaining ring without any difficulty.

  In the present invention, the shaft is inserted and fitted into the shaft hole of the inner joint member, and the retaining ring is fitted in an annular groove formed on the outer peripheral surface of the shaft in a reduced diameter state, and the shaft is pulled out from the inner joint member. The bottom surface of the annular groove of the shaft is gradually enlarged from the inlet side to the inner side of the inner joint member.

  With such a structure, the diameter reduction force of the retaining ring generates a component force in the axial direction, and the retaining ring moves to the inlet side of the inner joint member by this axial component force, and the inner joint member Abuts on the back end face. Alternatively, the other part of the inner diameter of the retaining ring that is not in contact with the bottom surface of the annular groove is reduced in diameter so as to come into contact with the bottom surface of the annular groove with the above-described reduction force, so that the entire retaining ring is made of the inner joint member. The outer diameter side end surface of the retaining ring is in contact with the inner side end surface of the inner joint member by tilting toward the inlet side.

  As a result, since the inner joint member is restrained in the axial direction with respect to the shaft without any gap, there is no axial backlash between the inner joint member and the shaft, and vibration and noise can be prevented from occurring in advance. High constant velocity universal joints can be provided.

  Embodiments of the present invention are described in detail below. In addition, although the following embodiment illustrates the case where it applies to the double offset type constant velocity universal joint (DOJ) which is one of the sliding type constant velocity universal joints, a cross groove type constant velocity universal joint (LJ) or The present invention can also be applied to other sliding type constant velocity universal joints such as a tripod type constant velocity universal joint (TJ). Furthermore, the present invention is also applicable to fixed type constant velocity universal joints such as a Barfield type constant velocity universal joint (BJ) and an undercut free type constant velocity universal joint (UJ).

  The constant velocity universal joint of the embodiment shown in FIG. 2 includes an outer ring 10 as an outer joint member in which a plurality of linear track grooves 12 parallel to the axis are formed on the cylindrical inner peripheral surface 14 at equal intervals in the circumferential direction, A plurality of linear track grooves 22 parallel to the axis corresponding to the track grooves 12 of the outer ring 10 are formed on the spherical outer peripheral surface 24 at equal intervals in the circumferential direction. The track grooves 12 and the track grooves 22 of the inner ring 20 are arranged on a ball track formed in cooperation to transmit a plurality of balls 30 for transmitting torque, the cylindrical inner peripheral surface 14 of the outer ring 10 and the spherical shape of the inner ring 20. A cage 40 interposed between the outer peripheral surface 24 and holding the ball 30.

  Each ball 30 is accommodated in each of a plurality of pockets 42 formed in the cage 40 and arranged at equal intervals in the circumferential direction. The number of balls 30 is six or eight, but other numbers may be used.

  When this constant velocity universal joint is used for a drive shaft, a shaft portion 16 that extends integrally from one end of the outer ring 10 in the axial direction is connected to the differential, and a shaft 60 that is spline-fitted into the shaft hole 26 of the inner ring 20 is provided. It is connected to a fixed constant velocity universal joint.

  When the outer ring 10 and the inner ring 20 are angularly displaced between the shaft portion 16 of the outer ring 10 and the shaft 60 on the inner ring 20 side, the ball 30 accommodated in the pocket 42 of the cage 40 is always at any operating angle. The operating angle is maintained in the bisection plane, and the constant velocity of the joint is ensured.

  A structure in which the shaft end of the shaft 60 is inserted into the shaft hole 26 of the inner ring 20 is adopted as a connection structure between the inner ring 20 and the shaft 60 of the sliding type constant velocity universal joint. A female spline 28 is formed on the inner diameter of the shaft hole 26 of the inner ring 20 as irregularities along the axial direction, and a male spline 68 is also formed on the outer diameter of the shaft end of the shaft 60.

  By inserting the shaft end of the shaft 60 into the shaft hole 26 of the inner ring 20 and engaging the male spline 68 and the female spline 28, the shaft 60 is fitted to the inner ring 20 so that torque can be transmitted between them. In addition, the connection structure of the inner ring 20 and the shaft 60 is not limited to the above-described spline fitting, and may be other uneven fitting that can transmit torque.

  As shown in FIG. 3, the shaft 60 fitted to the inner ring 20 of the constant velocity universal joint forms an annular groove 62 on the outer peripheral surface of the shaft end, and the bottom surface 64 of the annular groove 62 serves as the axis of the inner ring 20. The diameter is gradually increased from the entrance side to the back side of the inner ring 20 into which the shaft 60 is inserted into the hole 26. The bottom surface 64 of the annular groove 62 in this embodiment is a tapered surface that is linear in the cross section in the shaft axial direction. In addition, the annular groove 62 has a back end surface 66 standing in a direction orthogonal to the shaft axial direction and continuously formed from the bottom surface 64 toward the shaft axial end.

  In the fitting structure of the inner ring 20 and the shaft 60 in the embodiment shown in FIG. 1, the retaining ring 70 is fitted into the annular groove 62 of the shaft 60 inserted into the shaft hole 26 of the inner ring 20, and the shaft 60 is fitted to the inner ring 20. It has a structure that prevents it from coming off.

As shown in FIGS. 4A and 4B, the retaining ring 70 is made of a C-shaped elastic member so that the diameter can be increased. The retaining ring 70 is set so that the inner diameter D ₁ when free is smaller than the inner diameter D ₂ when it is mounted in the annular groove 62 of the shaft 60. Thereby, in a state where the retaining ring 70 is mounted on the shaft 60, a diameter reducing force acts inward in the radial direction.

  The procedure for assembling the shaft 60 to the inner ring 20 is as follows. First, the shaft 60 is inserted from the inlet side opening end 21 of the shaft hole 26 of the inner ring 20. The shaft 60 is inserted to a position where an annular groove 62 formed on the outer peripheral surface of the shaft end protrudes from the rear opening end 23 of the inner ring 20. By inserting the shaft 60, the female spline 28 of the shaft hole 26 of the inner ring 20 and the male spline 68 on the outer peripheral surface of the shaft 60 are engaged with each other and are spline-fitted, so that torque can be transmitted between them.

  In this state, as shown in FIG. 5, the retaining ring 70 is fitted into the annular groove 62 of the shaft 60 in a state where the diameter of the retaining ring 70 is larger than that in the natural state (see the broken line in the figure). The retaining ring 70 fitted in the annular groove 62 is reduced in diameter radially inward by an elastic restoring force to a natural state.

  At this time, the retaining ring 70 applies a force to the annular groove 62 of the shaft 60 to reduce the diameter inward in the radial direction with an elastic restoring force to a natural state. Here, the bottom surface 64 of the annular groove 62 with which the inner diameter 72 of the retaining ring 70 abuts is tapered so that the diameter gradually increases from the inlet side to the inner side of the inner ring 20. Radial force generates axial component force. Due to this axial component force, the retaining ring 70 moves to the inlet side of the inner ring 20 and comes into contact with the inner end surface 25 of the inner ring 20 (see the solid line in the figure). As a result, the inner ring 20 is restrained with respect to the shaft 60 without any gap in the axial direction. That is, the inner ring 20 is sandwiched between the shoulder portion of the shaft 60 and the retaining ring 70 without any play.

  The annular groove 62 has a structure in which a rear side end surface 66 continuously formed from the bottom surface 64 toward the shaft shaft end side stands up in a direction orthogonal to the shaft axis direction. As a result, even when a large pulling force is applied to the shaft 60, the retaining ring 70 comes into contact with and engages with the rear end surface 66 of the annular groove 62, thereby preventing the shaft 60 from coming off from the inner ring 20. Become strong.

  The retaining rings 70a and 70b can also have a shape in which the inner diameters 72a and 72b are gradually expanded from the inlet side to the inner side of the inner ring 20 as shown in FIGS. 6 (a) and 6 (b). is there. FIG. 5A illustrates a tapered surface in which the inner diameter shape of the retaining ring 70a is linear in the cross section in the shaft axial direction, and FIG. 5B illustrates the inner diameter shape of the retaining ring 70b in a curved shape in the cross section in the shaft axial direction. An example of the convex curved surface is shown.

  When the inner diameters 72a and 72b of the retaining rings 70a and 70b are formed as shown in FIGS. 6A and 6B, the inner diameters 72a and 72b of the retaining rings 70a and 70b are in contact with the bottom surface 64 of the annular groove 62 at the edge. Therefore, when the retaining rings 70a, 70b are fitted into the annular groove 62, the retaining rings 70a, 70b are smoothly moved to the inlet side of the inner ring 20 by the axial component force generated by the diameter reducing force of the retaining rings 70a, 70b. It becomes easy to move to. As a result, the inner ring 20 is more reliably restrained in the axial direction with respect to the shaft 60 without a gap. In other words, the inner ring 20 is sandwiched between the shoulder portion of the shaft 60 and the retaining rings 70a and 70b without play.

  In the above-described embodiment, the retaining ring 70 acts on the annular groove 62 of the shaft 60 by applying a force that shrinks radially inward with an elastic restoring force to a natural state. The case where the retaining ring 70 moves to the inlet side of the inner ring 20 by the generated axial component force and contacts the inner end surface 25 of the inner ring 20 has been described. However, the material and shape of the retaining ring 70 or the shape of the annular groove Depending on the situation, the inner ring 20 may be restrained in the axial direction with no gap in the axial direction as follows.

  That is, as shown in FIG. 7, when the retaining ring 70 is fitted in the annular groove 62 of the shaft 60 in a state where the diameter of the retaining ring 70 is larger than the diameter in the natural state (see the broken line in the figure), the retaining ring 70 is in the natural state. The diameter is reduced radially inward by an elastic restoring force.

  At this time, the bottom surface 64 of the annular groove 62 with which the inner diameter 72 of the retaining ring 70 abuts is tapered so that the diameter gradually increases from the inlet side to the inner side of the inner ring 20. The inner ring back side edge portion of 72 is in contact with the bottom surface 64 of the annular groove 62, and the inner ring inlet side edge portion of the inner diameter 72 of the retaining ring 70 is not in contact with the bottom surface 64 of the annular groove 62.

  The inner ring inlet side edge portion of the inner diameter 72 of the retaining ring 70 that is not in contact with the bottom surface 64 of the annular groove 62 is reduced in diameter so as to come into contact with the bottom surface 64 of the annular groove 62 with a diameter reducing force. Is inclined toward the inlet side of the inner ring 20, and the outer diameter side end surface 74 of the retaining ring 70 comes into contact with the inner side end surface 25 of the inner ring 20 (see the solid line in the figure). As a result, the inner ring 20 is restrained with respect to the shaft 60 without any gap in the axial direction. That is, the inner ring 20 is sandwiched between the shoulder portion of the shaft 60 and the retaining ring 70 without any play.

  The retaining rings 70c and 70d can also have a shape in which the inner diameters 72c and 72d are gradually reduced from the inlet side to the inner side of the inner ring 20 as shown in FIGS. 8 (a) and 8 (b). is there. FIG. 5A illustrates a tapered surface in which the inner diameter shape of the retaining ring 70c is linear in the cross section in the shaft axial direction, and FIG. 5B illustrates the inner diameter shape of the retaining ring 70d in a curved shape in the cross section in the shaft axial direction. An example of the convex curved surface is shown.

  When the inner diameters 72c and 72d of the retaining rings 70c and 70d are shaped as shown in FIGS. 8A and 8B, when the retaining rings 70c and 70d are fitted into the annular groove 62, the bottom surface 64 of the annular groove 62 and Since the inlet-side edge portions of the inner diameters 72c and 72d of the retaining rings 70c and 70d that are not in contact with each other can exert a large force to reduce the diameter so as to come into contact with the bottom surface 64 of the annular groove 62, the retaining ring as a whole is the inner ring 20. Inclined easily to the entrance side of the. As a result, the inner ring 20 is more reliably restrained in the axial direction with respect to the shaft 60 without a gap. That is, the inner ring 20 is sandwiched between the shoulder portion of the shaft 60 and the retaining rings 70c and 70d without play.

  As a form in which the inner ring 20 is constrained in the axial direction with respect to the shaft 60, as shown in FIG. 5, the retaining ring 70 is brought into the inlet of the inner ring 20 by the axial component force generated by the diameter reducing force of the retaining ring 70. And the entire retaining ring is tilted toward the inlet side of the inner ring 20 due to the diameter reducing force of the retaining ring 70 as shown in FIG. The outer diameter side end surface 74 of the inner ring 20 may come into contact with the inner side ring 20 end surface 25. Which form is selected depends on the material and shape of the retaining ring 70 or the shape of the annular groove.

  For example, when the retaining ring 70 has a large bending rigidity, the retaining ring 70 moves to the inlet side of the inner ring 20 by the axial component force generated by the diameter reducing force of the retaining ring 70 as shown in FIG. When the retaining ring 70 is small in bending rigidity, the entire retaining ring is brought into contact with the inlet of the inner ring 20 by the diameter reducing force of the retaining ring 70 as shown in FIG. The main case is that the outer diameter side end surface 74 of the retaining ring 70 is in contact with the inner side end surface 25 of the inner ring 20 by tilting to the side.

  The bending rigidity of the retaining ring 70 in the configuration shown in FIG. 7 is smaller than the bending rigidity of the retaining ring 70 in the configuration shown in FIG. 5, but even in that case, it is added to the shaft 60. The bending rigidity is ensured to such an extent that the retaining ring 70 can exhibit a retaining function against the pulling force from the axial direction.

  In the above embodiment, the bottom surface 64 of the annular groove 62 is an annular shape that gradually increases in diameter from the inlet side of the inner ring 20 into which the shaft 60 is inserted into the shaft hole 26 of the inner ring 20 toward the back side. Although the case where the bottom surface 64 of the groove 62 is a tapered surface that is linear in the cross section in the axial direction of the shaft has been described, the present invention is not limited to this and a structure as shown in FIGS. 9 and 10 is also possible. .

  That is, as another form of gradually increasing the diameter of the bottom surface 64 of the annular groove 62 from the inlet side of the inner ring 20 into which the shaft 60 is inserted into the shaft hole 26 of the inner ring 20 toward the back side, the annular grooves 62a and 62b. Further, curved surfaces in which the bottom surfaces 64a and 64b are curved in the shaft axial section are also possible. FIG. 9 shows a convex curved surface, and FIG. 10 shows a concave curved surface.

  Even when the bottom surfaces 64a and 64b of the annular grooves 62a and 62b are convex curved surfaces as shown in FIG. 9 or concave curved surfaces as shown in FIG. 10, they are the same as the tapered surfaces shown in FIG. In order to achieve the effect, duplicate description is omitted. 9 and 10 can also be applied to the retaining rings 70a to 70d having the inner diameter shapes shown in FIGS. 6 (a), 6 (b) and 8 (a), 8 (b). There are similar effects.

Further, the annular groove 62 of the shaft 60 may have a shape shown in FIG. The annular groove 62c has a bottom surface 64c having a V-shaped cross section in the shaft axial direction. In other words, a linear taper in which the diameter is gradually increased from the inlet side of the inner ring 20 into which the shaft 60 is inserted into the shaft hole 26 of the inner ring 20 toward the inner side, which is the shaft shaft end side. A linear tapered surface having a surface 64c ₁ and gradually reducing the diameter from the inlet side to the inner side of the inner ring 20 where the shaft 60 is inserted into the shaft hole 26 of the inner ring 20 on the inlet side of the inner ring 20. with a 64c _2.

  In the case of the annular groove 62c having such a shape, when the retaining ring 70 is fitted into the annular groove 62c of the shaft 60, the diameter reducing force of the retaining ring 70 acting on the annular groove 62c of the shaft 60 is reduced as shown in FIG. Due to the generated axial force, the retaining ring 70 moves to the inlet side of the inner ring 20 and comes into contact with the inner end face 25 of the inner ring 20.

At this time, the inner ring inner edge 72 of the inner diameter 72 of the retaining ring 70 is linearly expanded gradually from the inlet side of the inner ring 20 into which the shaft 60 is inserted into the shaft hole 26 of the inner ring 20 toward the inner side. Although abuts the tapered surface 64c ₁ of the inner ring inlet-side edge portion of the inner diameter 72 of the retaining ring 70, toward the inlet side of the inner ring 20 of the shaft 60 to the shaft hole 26 of the inner ring 20 is inserted into the inner side It does not come into contact with the linear taper surface 64c ₂ that has been gradually reduced in diameter. As a result, the inner ring 20 is restrained with respect to the shaft 60 without any gap in the axial direction. In other words, the inner ring 20 is sandwiched between the shoulder portion of the shaft 60 and the retaining ring 70 without play.

  When manufacturing the annular grooves 62, 62a and 62b having the bottom surfaces 64, 64a and 64b having the shapes shown in FIGS. 3, 9 and 10, it is necessary to use a dedicated tool for the groove processing. On the other hand, when the annular groove 62c having the bottom surface 64c having the shape shown in FIG. 11 is manufactured, it is effective in that the groove can be formed with a general cutting tool.

  Further, in the annular grooves 62, 62a, and 62b shown in FIGS. 3, 9, and 10, there are back end surfaces 66, 66a, and 66b formed continuously from the bottom surfaces 64, 64a, and 64b toward the shaft shaft end side. The structure stands up in a direction perpendicular to the shaft axis direction. On the other hand, in the annular groove 62c shown in FIG. 11, there is no back side end surface that functions as a stopper when a large pulling force acts on the shaft 60.

Therefore, the diameter is gradually increased from the inlet side of the inner ring 20 into which the shaft 60 is inserted into the shaft hole 26 of the inner ring 20 toward the inner side so that the shaft 60 does not come out of the inner ring 20 below an arbitrary pulling force. The angle θ of the linear tapered surface 64c ₁ may be set appropriately.

  The present invention is not limited to the above-described embodiments, and can of course be implemented in various forms without departing from the gist of the present invention. It includes the equivalent meanings recited in the claims and the equivalents recited in the claims, and all modifications within the scope.

FIG. 3 is an enlarged cross-sectional view of a main part showing a fitting structure between an inner ring and a shaft in the embodiment of the present invention. It is a longitudinal section showing the whole sliding constant velocity universal joint composition in an embodiment of the present invention. In the embodiment of the present invention, as one form of gradually reducing the diameter of the bottom surface of the annular groove from the shaft shaft end side toward the inner ring side, the shaft having the bottom surface of the annular groove as a linear taper surface in the shaft axial section FIG. (A) is a side view which shows the retaining ring of FIG. 1, (b) is sectional drawing which shows the retaining ring of FIG. FIG. 5 is an enlarged cross-sectional view showing a main part of an embodiment in which the inner ring is restrained in the axial direction with respect to the shaft without a gap by the retaining ring of FIG. In another embodiment of the present invention, (a) is a cross-sectional view showing a retaining ring having a tapered surface in which the inner diameter gradually increases from the inlet side to the inner side of the inner ring and is linear in the axial section of the shaft, (B) is a cross-sectional view showing a retaining ring having a convexly curved surface whose inner diameter is gradually increased from the inlet side to the inner side of the inner ring and is curved in the shaft axial section. It is a principal part expanded sectional view which shows the other form with which an inner ring | wheel is restrained with a clearance gap between an axial direction with respect to a shaft by the retaining ring of FIG. In another embodiment of the present invention, (a) is a cross-sectional view showing a retaining ring having a tapered surface in which the inner diameter is gradually reduced from the inlet side to the inner side of the inner ring, and is linear in the shaft axial section, (B) is a cross-sectional view showing a retaining ring having a convex curved surface whose inner diameter is gradually reduced from the inlet side to the inner side of the inner ring and is curved in the shaft axial section. In another embodiment of the present invention, as another form of gradually reducing the diameter of the bottom surface of the annular groove from the shaft shaft end side toward the inner ring side, the bottom surface of the annular groove is formed in a curved convex curve in the shaft axial section. It is a front view which shows the shaft made into the surface. In another embodiment of the present invention, as another form of gradually reducing the diameter of the bottom surface of the annular groove from the shaft shaft end side toward the inner ring side, the bottom surface of the annular groove is formed into a curved concave curve in the axial section of the shaft. It is a front view which shows the shaft made into the surface. It is a front view which shows the shaft which formed the annular groove which has a V-shaped bottom face in the shaft axial direction cross section in other embodiment of this invention. As another form in which the inner ring is restrained in the axial direction with respect to the shaft without a gap by the retaining ring in FIG. 4, an enlarged cross-sectional view of a main part showing a state in which the retaining ring in FIG. 4 is mounted in the annular groove of the shaft in FIG. It is. It is sectional drawing which shows the whole structure of the conventional constant velocity universal joint. It is sectional drawing which shows the fitting structure of the inner ring | wheel and shaft in the conventional constant velocity universal joint.

Explanation of symbols

10 Outer joint member (outer ring)
20 Inner joint member (inner ring)
25 Inner side of inner joint member 26 Shaft hole 60 Shaft 62 Annular groove 64 Bottom surface of annular groove 66 Inner end surface of annular groove 70 Retaining ring 72 Inner diameter of retaining ring

Claims (6)

  A constant velocity universal joint comprising an outer joint member and an inner joint member that transmits torque while allowing angular displacement between the outer joint member, and a shaft is inserted into the shaft hole of the inner joint member And having a structure in which a retaining ring is fitted in an annular groove formed on the outer peripheral surface of the shaft in a reduced diameter state to prevent the shaft from coming off with respect to the inner joint member. A constant velocity universal joint having a reduced diameter surface that gradually decreases in diameter from the shaft shaft end side toward the inner joint member side.   2. The constant velocity universal joint according to claim 1, wherein the annular groove of the shaft includes an end surface that is continuously formed from the reduced diameter surface toward the shaft shaft end side and rises in a direction orthogonal to the shaft axis direction. .   The constant velocity universal joint according to claim 1, wherein the reduced diameter surface is linear in a cross section in the shaft axial direction.   The constant velocity universal joint according to claim 1, wherein the reduced diameter surface has a curved shape in a cross section in the shaft axial direction.   The constant velocity universal joint according to any one of claims 1 to 4, wherein an inner diameter of the retaining ring is gradually expanded from the inner joint member side toward the shaft shaft end side.   The constant velocity universal joint according to any one of claims 1 to 4, wherein an inner diameter of the retaining ring is gradually reduced in diameter from the inner joint member side toward the shaft shaft end side.

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