JP6459664B2 - Constant velocity joint - Google Patents

Description

  The present invention relates to a constant velocity joint.

  Patent Document 1 describes a constant velocity joint including a rolling element unit in which an axial rolling element circulates around an outer periphery. In the constant velocity joint, the axial rolling element rolls on the side surface of the raceway groove of the outer joint member. Furthermore, the rolling part of the axial rolling element is regulated in the groove depth direction of the raceway groove with respect to the concave rolling surface on the side surface of the raceway groove. As a result, the posture of the rolling element unit is restricted with respect to the raceway groove.

JP 2013-174362 A

  By the way, although the rolling element unit is basically restricted in posture with respect to the raceway groove, the rolling element unit is tilted with respect to the raceway groove to a small extent for ease of assembly. Furthermore, the axial rolling element circulates around the outer periphery of the rolling element unit. Therefore, when the rolling element unit is tilted with respect to the raceway groove, when the rolling element enters the rolling surface, the rolling element comes into contact with the shoulder of the concave rolling surface. End up. The contact force at this time becomes the resistance of circulation of the axial rolling element. As for the circulation resistance of the shaft-like rolling element, the constant velocity joint induces a thrust force.

  An object of the present invention is to provide a constant velocity joint capable of reducing the induced thrust force by suppressing contact force generated when the axial rolling element enters the rolling surface on the side surface of the raceway groove. To do.

  The constant velocity joint of the first invention is formed in a cylindrical shape, an outer joint member in which a plurality of raceway grooves are formed on an inner peripheral surface, an inner joint member provided with a plurality of leg shafts projecting radially outward, An inner member supported by the outer peripheral surface of the leg shaft, and a plurality of axial rolling elements that circulate along the outer periphery of the inner member and roll on the side surface of the raceway groove and the outer peripheral surface of the inner member. It is a constant velocity joint.

  The side surface of the raceway groove is a rolling surface having a width larger than the axial length of the rolling portion of the shaft-like rolling element, an opening side shoulder portion formed on the opening side of the raceway groove on the rolling surface, and A bottom side shoulder formed on the bottom side of the raceway groove of the rolling surface is provided. When the shaft-like rolling element enters the rolling surface after the opening-side end of the shaft-like rolling element contacts the first contact point of the opening-side shoulder, it is perpendicular to the axial direction of the outer joint member. A vector that is directed to the first contact point in a trajectory of the opening side end portion entering the first contact point on the plane to be defined as a first entry vector, and the first contact at a tangent to a side surface of the track groove A vector from the opening side of the point to the bottom side is defined as a first tangent vector. The opening-side shoulder is formed so that an angle formed by the first approach vector and the first tangent vector is an acute angle.

  The constant velocity joint of the second invention is formed in a cylindrical shape, an outer joint member formed with a plurality of raceway grooves on the inner peripheral surface, an inner joint member provided with a plurality of leg shafts projecting radially outward, An inner member supported by the outer peripheral surface of the leg shaft, and a plurality of axial rolling elements that circulate along the outer periphery of the inner member and roll on the side surface of the raceway groove and the outer peripheral surface of the inner member. It is a constant velocity joint.

  The side surface of the raceway groove is a rolling surface having a width larger than the axial length of the rolling portion of the shaft-like rolling element, an opening side shoulder portion formed on the opening side of the raceway groove on the rolling surface, and A bottom side shoulder formed on the bottom side of the raceway groove of the rolling surface is provided. In the case where the shaft-like rolling element enters the rolling surface after the opening-side end portion of the shaft-like rolling element contacts the first contact point of the opening-side shoulder, the opening-side shoulder portion is the rolling-side shoulder portion. A first regulating inclined surface that is located on the running surface side and regulates the attitude of the axial rolling element rolling on the rolling surface; and located on the opening side of the track groove from the first regulating inclined surface, A first introduction inclined surface having a first contact point and having a smaller inclination than the first regulating inclined surface.

  According to the constant velocity joint of the first invention, the opening-side shoulder is formed so that the angle formed by the first approach vector and the first tangent vector is an acute angle, so that the rolling element unit is in contact with the raceway groove. In the inclined state, when the axial rolling element enters the rolling surface, the axial rolling element is guided to the rolling surface side. That is, the contact force to the opening side shoulder by the axial rolling element is suppressed. Therefore, the induced thrust force due to the contact force is reduced.

  According to the constant velocity joint of the second invention, the opening-side shoulder portion has the first introduction inclined surface, so that the axial rolling element is in contact with the raceway groove in a state where the axial rolling element is inclined with respect to the raceway groove. When entering, the shaft-like rolling element comes into contact with the first introduction inclined surface having a small inclination. Therefore, the axial rolling element is guided to the rolling surface side. Therefore, the contact force to the opening shoulder by the shaft-like rolling element is reduced, and the induced thrust force due to the contact force is reduced. Moreover, when the opening-side shoulder portion has the first restriction inclined surface, the posture of the axial rolling element is restricted when the axial rolling element rolls on the rolling surface. That is, the posture of the rolling element unit is reliably regulated.

It is a perspective view which shows the axial direction cross section of the outer joint member of the constant velocity joint of this embodiment, and a partial cross section of a rolling element unit. It is a perspective view which shows an inner joint member and the rolling element unit from which the inner member was separated. It is the figure which looked at a part of constant velocity joint from the axial direction of the outer joint member. It is the figure seen from the normal line direction of the side surface of the raceway groove | channel of an outer joint member, and shows the state of the attitude | position which the rolling element unit inclined with respect to the raceway groove | channel of an outer joint member. The figure which shows the plane orthogonal to the axial direction of an outside joint member, shows the enlarged view of a raceway groove and a shaft-like rolling element, and shows the state just before a shaft-like rolling element enters into a rolling surface from the direction of an opening side shoulder. It is. It is a figure which shows a state when a shaft-shaped rolling element moves from the state shown in FIG. 5, and approached the rolling surface in the side surface of a track groove. FIG. 6 is an enlarged view of the vicinity of the opening-side shoulder on the side surface of the raceway groove in FIG. 5. The figure which shows the plane orthogonal to the axial direction of an outside joint member, shows an enlarged view of a raceway groove and a shaft-like rolling element, and shows a state just before a shaft-like rolling element enters a rolling surface from the bottom side shoulder It is. It is a figure which shows a state when a shaft-like rolling element moves from the state shown in FIG. 8, and entered the rolling surface in the side surface of a raceway groove. FIG. 9 is an enlarged view of the vicinity of a bottom shoulder on the side surface of the raceway groove in FIG. 8.

(1. Overall configuration of constant velocity joint 1)
The constant velocity joint 1 of this embodiment is demonstrated with reference to FIGS. 1-3. The constant velocity joint 1 is used, for example, for a power transmission shaft of a vehicle, and is used for a connection portion between a differential gear (not shown) and a wheel (not shown).

  The constant velocity joint 1 exemplifies a tripod type constant velocity joint as shown in FIG. The constant velocity joint 1 includes an outer joint member 10, an inner joint member 20, and three rolling element units 30. FIG. 1 shows a constant velocity joint 1 in which the angle formed by the rotation axis of the shaft 2 and the rotation axis of the outer joint member 10 (hereinafter also referred to as “joint angle”) is 0 °.

  The outer joint member 10 is formed in a cylindrical shape having an opening 11 on one side in the axial direction. The bottom outer side of the outer joint member 10 is connected to a differential. Three raceway grooves 12 extending in the axial direction of the outer joint member 10 from the opening 11 (left and right direction in FIG. 1) are formed at equal intervals in the circumferential direction on the inner peripheral surface of the cylindrical portion of the outer joint member 10. Is done.

  The cross-sectional shape orthogonal to the groove extending direction in the raceway groove 12 is a groove shape that opens toward the axis of the outer joint member 10. The raceway groove 12 is configured by a bottom surface 12a formed in a planar shape and a pair of side surfaces 12b located on both sides of the bottom surface 12a in the groove width direction and facing each other.

  As shown in FIG. 3, the side surface 12 b of the raceway groove 12 has a width W (which is larger than the axial length L (shown in FIGS. 4 and 5) of the rolling portion 61 of the shaft-like rolling body 60 constituting the rolling body unit 30. 4), the opening-side shoulder 17 formed on the opening side of the raceway groove 12 of the rolling surface 16, and the bottom surface 12 a side of the raceway groove 12 of the rolling surface 16. The bottom side shoulder 18 is provided.

  As shown in FIG. 1, the inner joint member 20 is a tripod in the present embodiment. The inner joint member 20 is disposed inside the outer joint member 10. The inner joint member 20 is movable and tiltable with respect to the outer joint member 10 in the axial direction of the outer joint member 10. As shown in FIG. 2, the inner joint member 20 includes a boss portion 21 formed in an annular shape, and three leg shafts 22 projecting radially outward from the boss portion 21. The boss portion 21 is integrally connected to the shaft 2 on the inner peripheral side. The outer peripheral surface of each leg shaft 22 is formed in a spherical convex shape, and is formed in a shape in which the central portion in the axial direction of the leg shaft 22 bulges most.

  As shown in FIG. 2, the rolling element unit 30 is formed in an annular shape. In the present embodiment, the outer shape of the rolling element unit 30 is formed in a shape that approximates a rectangular parallelepiped shape. The rolling element unit 30 is supported on the outer peripheral side of the leg shaft 22 and is supported to be tiltable with respect to the axis of the leg shaft 22. The rolling element unit 30 is movable along the side surface 12 b of the raceway groove 12 of the outer joint member 10. The rolling element unit 30 is interposed between the side surface 12b of the raceway groove 12 and the leg shaft 22, and is configured to be able to transmit torque between both members.

  As shown in FIG. 2, the rolling element unit 30 includes an inner member 40, a plurality of axial rolling elements 60, and a holding member 70, and the axial rolling element 60 circulates on the outer peripheral side of the rolling element unit 30. Type. The inner member 40 includes two divided members 41 and 42, and is formed in a shape that approximates an annular shape as a whole. The inner member 40 may be a member obtained by integrally molding the two divided members 41 and 42. The inner member 40 is provided so as to be tiltable with respect to each of the plurality of leg shafts 22, and enables the rolling element unit 30 to tilt with respect to the leg shafts 22. Further, the inner member 40 is provided so as to be able to transmit power to and from the leg shaft 22. Each of the split members 41 and 42 includes a pair of torque transmission surfaces 41a and 42a formed in a planar shape facing away from the outer peripheral surface. The torque transmission surfaces 41 a and 42 a face the side surface 12 b of the raceway groove 12.

  The axial rolling element 60 is provided between the side surface 12 b of the raceway groove 12 and the torque transmission surfaces 41 a and 42 a of the inner member 40 so as to roll along the rolling surface 16 on the side surface 12 b of the raceway groove 12. The axial rolling element 60 has a cylindrical outer peripheral surface and a rolling part 61 that rolls on the rolling surface 16, and a protruding part that protrudes from both ends of the rolling part 61 in the axial direction of the axial rolling element 60. 62.

  The holding member 70 holds the plurality of shaft-like rolling elements 60 so that the plurality of shaft-like rolling elements 60 can circulate around the outer periphery of the inner member 40. The holding member 70 is formed in an annular shape and surrounds the outer periphery of the inner member 40. The holding member 70 is configured by a pair of circulation path forming members that form a circulation path of the shaft-like rolling element 60 and latch the protrusion 62 of the shaft-like rolling element 60.

(2. Posture of rolling element unit 30)
Next, the posture when the rolling element unit 30 moves along the side surface 12b of the raceway groove 12 will be described with reference to FIG. The rolling part 61 of the shaft-like rolling element 60 rolls on the rolling surface 16 on the side surface 12 b of the raceway groove 12. That is, the rolling part 61 of the plurality of shaft-like rolling elements 60 rolling on the rolling surface 16 is locked to the opening-side shoulder 17 and the bottom-side shoulder 18, so that the rolling element unit 30 is connected to the outer joint. The posture of the member 10 is restricted.

  However, the width W of the rolling surface 16 is slightly larger than the axial length L (shown in FIGS. 4 and 5) of the rolling part 61 of the axial rolling element 60. Therefore, as shown in FIG. 4, the circulation plane of the axial rolling element 60 is slightly inclined with respect to the direction in which the rolling surface 16 extends. When the rolling element unit 30 moves from the back side (right side in FIG. 1) of the outer joint member 10 to the opening 11 side (left side in FIG. 1), along with the tilt of the leg shaft 22 of the inner joint member 20, The rolling element unit 30 is in the posture shown in FIG. On the other hand, when the rolling element unit 30 moves from the opening 11 side (left side in FIG. 1) to the back side (right side in FIG. 1) of the outer joint member 10, the leg shaft 22 of the inner joint member 20 is tilted. Thus, the rolling element unit 30 is inclined in the direction opposite to that in FIG. Further, when the shaft-like rolling element 60 enters the rolling surface 16, the shaft-like rolling element 60 comes into contact with the opening-side shoulder 17 of the side surface 12 b according to the circulation direction of the shaft-like rolling element 60, and the shaft In some cases, the rolling element 60 contacts the bottom shoulder 18 of the side surface 12b.

(3. Detailed shape of side surface 12b of raceway groove 12)
Next, the detailed shape of the side surface 12b of the raceway groove 12 will be described with reference to FIGS. The detailed shape of the side surface 12 b of the raceway groove 12 will be described with reference to the locus of the axial rolling element 60. Therefore, first, the case where the axial rolling element 60 enters the rolling surface 16 in a posture in which the rolling element unit 30 is inclined with respect to the rolling surface 16 as shown in FIG. 4 will be described.

  As shown in FIG. 4, when the rolling element unit 30 is inclined with respect to the rolling surface 16, there are the following two cases where the axial rolling element 60 enters the rolling surface 16. The first case is a case where the state shown in FIG. 5 is shifted to the state shown in FIG. 6, that is, the opening side end 61a of the rolling part 61 of the shaft-like rolling element 60 is the opening side shoulder 17 of the side face 12b. This is a case where the shaft-like rolling element 60 enters the rolling surface 16 after contacting with. In the second case, when the state shown in FIG. 8 shifts to the state shown in FIG. 9, that is, after the bottom surface side end portion 61b of the shaft-shaped rolling element 60 contacts the bottom surface side shoulder portion 18 of the side surface 12b, This is a case where the shaft-shaped rolling element 60 enters the rolling surface 16.

  In FIG. 7, the thin broken line, the middle thick broken line, and the thick broken line are all outlines of the rolling part 61 of the axial rolling element 60. The rolling part 61 indicated by the thin broken line is in a state where it does not contact the side surface 12b of the raceway groove 12, and the rolling part 61 indicated by the middle thick broken line is in contact with the opening side shoulder 17 of the side face 12b. The rolling part 61 indicated by a thick broken line is in a state of contacting the rolling surface 16.

  The shape of the opening-side shoulder 17 on the side surface 12b of the raceway groove 12 is as shown in FIG. As shown in FIG. 7, the opening-side shoulder 17 includes a first regulating inclined surface 17a and a first introduction inclined surface 17b. The first regulating inclined surface 17 a is a surface that regulates the posture of the axial rolling element 60 that rolls on the rolling surface 16. The first regulating inclined surface 17a regulates the skew of the axial rolling element 60. The first regulating inclined surface 17 a is not a surface orthogonal to the rolling surface 16 but is inclined so as to spread toward the opening side of the raceway groove 12. The first restriction inclined surface 17 a includes a first restriction point Pa <b> 1 with which the opening-side end 61 a of the rolling part 61 of the shaft-like rolling element 60 that rolls on the rolling surface 16 contacts. In addition, in this embodiment, although the 1st control inclination surface 17a is formed in planar shape, you may form in curved surface shape.

  The first introduction inclined surface 17b is located closer to the opening side of the raceway groove 12 than the first restricting inclined surface 17a, and is a surface having a lower inclination than the first restricting inclined surface 17a. The inclination here is an inclination based on the rolling surface 16. The first introduction inclined surface 17b is formed in the axial rolling element 60 after the opening side end 61a of the rolling part 61 of the axial rolling element 60 in the first case contacts the opening side shoulder 17 of the side surface 12b. Is provided with a first contact point Pb1 with the opening-side end 61a of the rolling part 61 of the shaft-like rolling element 60. Further, the first regulating inclined surface 17a and the first introduction inclined surface 17b are connected so that the contact surfaces are continuous. In the present embodiment, the first introduction inclined surface 17b is formed in a flat shape, but may be formed in a curved surface shape.

  FIG. 7 shows a plane orthogonal to the axial direction of the outer joint member 10, and the opening-side shoulder 17 exists when the axial rolling element 60 shifts from the state shown in FIG. 5 to the state shown in FIG. 6. The trajectory T1 of the opening-side end 61a of the rolling part 61 of the shaft-like rolling element 60 in the case of not being indicated is indicated by a two-dot chain line. That is, the trajectory T <b> 1 passes through the first contact point Pb <b> 1, passes through the site of the opening-side shoulder 17, and enters the rolling surface 16. The trajectory T1 is in the order of A1 → first contact point Pb1 → B1 → rolling surface 16.

  Here, as shown in FIG. 7, on the plane orthogonal to the axial direction of the outer joint member 10, the locus of the opening side end 61a of the rolling part 61 of the axial rolling element 60 entering the first contact point Pb1. A vector toward the first contact point Pb1 at T1 is defined as a first approach vector Vi1. Further, on the same plane, a vector from the opening side of the raceway groove 12 to the bottom surface 12a side of the first contact point Pb1 on the tangent line of the side surface 12b of the raceway groove 12 is defined as a first tangent vector Vs1.

  Then, the first introduction inclined surface 17b of the opening-side shoulder 17 is formed so that the angle θ1 formed by the first approach vector Vi1 and the first tangent vector Vs1 is an acute angle. The angle θ1 formed corresponds to an inferior angle formed by the half line indicated by the first approach vector Vi1 and the half line indicated by the first tangent vector Vs1. In particular, the rolling surface 16 is formed parallel to the axis of the leg shaft 22 so that the first tangent vector Vs1 is farther from the opening side of the raceway groove 12 to the bottom surface side than the axis of the leg shaft 22. The first introduction inclined surface 17b is formed to be inclined.

  In the case where the opening-side shoulder 17 is formed as described above, the opening-side end 61 a actually moves along the surface of the opening-side shoulder 17. That is, the actual trajectory of the opening side end 61a is in the order of A1 → C1 (including the first contact point Pb1) → D1 → the rolling surface 16. Therefore, the opening side end portion 61a smoothly enters the rolling surface 16 from the first contact point Pb1.

  The shape of the bottom-side shoulder 18 on the side surface 12b of the raceway groove 12 is as shown in FIG. As shown in FIG. 10, the bottom side shoulder 18 includes a second regulating inclined surface 18 a and a second introduction inclined surface 18 b. The 2nd control inclination surface 18a is a surface which controls the attitude | position of the axial rolling element 60 which rolls the rolling surface 16 with the 1st control inclination surface 17a. The second regulating inclined surface 18a regulates the skew of the axial rolling element 60. The second regulating inclined surface 18 a is not a surface orthogonal to the rolling surface 16 but is inclined so as to spread toward the bottom surface 12 a side of the raceway groove 12. The second restriction inclined surface 18 a includes a second restriction point Pa <b> 2 where the bottom surface side end 61 b of the rolling part 61 of the shaft-like rolling element 60 that rolls on the rolling surface 16 contacts. In addition, in this embodiment, although the 2nd control inclination surface 18a is formed in planar shape, you may form in curved surface shape.

  The second introduction inclined surface 18b is located on the bottom surface 12a side of the raceway groove 12 with respect to the second restricting inclined surface 18a, and has a smaller inclination than the second restricting inclined surface 18a. The second introduction inclined surface 18b is formed in the axial rolling element 60 after the bottom surface side end 61b of the rolling part 61 of the axial rolling element 60 in the second case is in contact with the bottom surface side shoulder 18 of the side surface 12b. , When entering the rolling surface 16, the second contact point Pb <b> 2 with the bottom surface side end portion 61 b of the rolling portion 61 of the axial rolling element 60 is provided. Further, the second regulating inclined surface 18a and the second introduction inclined surface 18b are connected so that the contact surfaces are continuous. In the present embodiment, the second introduction inclined surface 18b is formed in a planar shape, but may be formed in a curved surface shape.

  FIG. 10 shows a plane orthogonal to the axial direction of the outer joint member 10, and there is a bottom side shoulder 18 when the axial rolling element 60 transitions from the state shown in FIG. 8 to the state shown in FIG. 9. The trajectory T2 of the bottom surface side end portion 61b of the rolling portion 61 of the shaft-like rolling element 60 in the case of not being indicated is indicated by a two-dot chain line. That is, the trajectory T <b> 2 passes through the second contact point Pb <b> 2, passes through the bottom-side shoulder 18, and enters the rolling surface 16. The trajectory T2 is in the order of A2 → second contact point Pb2 → B2 → rolling surface 16.

  Here, as shown in FIG. 10, on the plane orthogonal to the axial direction of the outer joint member 10, the bottom surface side end portion 61b of the rolling portion 61 of the axial rolling element 60 enters the second contact point Pb2. A vector toward the second contact point Pb2 at T2 is defined as a second approach vector Vi2. In addition, on the same plane, a vector from the bottom surface 12a side of the raceway groove 12 to the opening side of the raceway groove 12 at the second contact point Pb2 on the tangent line of the side surface 12b of the raceway groove 12 is defined as a second tangent vector Vs2.

  Then, the second introduction inclined surface 18b of the bottom side shoulder 18 is formed so that the angle θ2 formed by the second approach vector Vi2 and the second tangent vector Vs2 is an acute angle. The angle θ2 formed corresponds to an inferior angle formed by the half line indicated by the second approach vector Vi2 and the half line indicated by the second tangent vector Vs2. In particular, the rolling surface 16 is formed parallel to the axis of the leg shaft 22 so that the second tangent vector Vs2 is farther from the bottom surface 12a side of the raceway groove 12 on the opening side than the axis of the leg shaft 22. In addition, the second introduction inclined surface 18b is formed to be inclined.

  When the bottom-side shoulder 18 is formed as described above, the bottom-side end 61 b actually moves along the surface of the bottom-side shoulder 18. That is, the actual trajectory of the bottom-side end 61b is in the order of A2 → C2 (including the second contact point Pb2) → D2 → the rolling surface 16. Therefore, the bottom surface side end 61b smoothly enters the rolling surface 16 from the second contact point Pb2.

(4. Effects of the embodiment)
The constant velocity joint 1 of the above embodiment is formed in a cylindrical shape, and includes an outer joint member 10 having a plurality of raceway grooves 12 formed on an inner peripheral surface, and an inner side provided with a plurality of leg shafts 22 projecting radially outward. The joint member 20, the inner member 40 supported by the outer peripheral surface of the leg shaft 22, and the plurality of members that circulate along the outer periphery of the inner member 40 and roll on the side surface 12 b of the raceway groove 12 and the outer peripheral surface of the inner member 40. A shaft-shaped rolling element 60 is provided.

  The side surface 12b of the raceway groove 12 has a rolling surface 16 having a width W greater than the axial length L of the rolling part 61 of the axial rolling element 60, and an opening side formed on the opening side of the raceway groove 12 on the rolling surface 16. The shoulder part 17 and the bottom face side shoulder part 18 formed in the bottom face 12a side of the raceway groove | channel 12 of the rolling surface 16 are provided.

  When the axial rolling element 60 enters the rolling surface 16 after the opening end 61a of the axial rolling element 60 contacts the first contact point Pb1 of the opening shoulder 17, the axial direction of the outer joint member 10 is reached. Is defined as a first approach vector Vi1 in a trajectory T1 where the opening-side end 61a enters the first contact point Pb1, and the tangent to the side surface 12b of the track groove 12 is defined as a first approach vector Vi1. , The vector from the opening side to the bottom surface 12a side of the first contact point Pb1 is defined as a first tangent vector Vs1, and the opening is set so that the angle θ1 formed by the first approach vector Vi1 and the first tangent vector Vs1 is an acute angle. A side shoulder 17 is formed.

  According to the constant velocity joint 1, the opening-side shoulder portion 17 is formed so that the angle θ1 formed by the first approach vector Vi1 and the first tangent vector Vs1 is an acute angle, whereby the rolling element unit 30 is formed in the raceway groove 12. When the shaft-like rolling element 60 enters the rolling surface 16 in a state of being inclined with respect to the shaft, the shaft-like rolling member 60 is guided to the rolling surface 16 side. That is, the contact force to the opening-side shoulder 17 by the axial rolling element 60 is suppressed. Therefore, the induced thrust force due to the contact force is reduced.

  In the constant velocity joint 1, when the axial rolling element 60 enters the rolling surface 16 after the bottom end 61 b of the axial rolling element 60 contacts the second contact point Pb 2 of the bottom shoulder 18. In addition, on the plane perpendicular to the axial direction of the outer joint member 10, a vector toward the second contact point Pb2 in the trajectory T2 where the bottom surface side end 61b enters the second contact point Pb2 is defined as a second entry vector Vi2. A vector from the bottom surface 12a side to the opening side of the second contact point Pb2 on the tangent to the side surface 12b of the raceway groove 12 is defined as a second tangent vector Vs2, and an angle θ2 formed by the second approach vector Vi2 and the second tangent vector Vs2 is defined. The bottom-side shoulder 18 is formed so that is an acute angle.

  According to the constant velocity joint 1, the bottom surface side shoulder portion 18 is formed so that the angle θ2 formed by the second approach vector Vi2 and the second tangent vector Vs2 is an acute angle, whereby the rolling element unit 30 is formed in the raceway groove 12. When the shaft-like rolling element 60 enters the rolling surface 16 in a state of being inclined with respect to the shaft, the shaft-like rolling member 60 is guided to the rolling surface 16 side. That is, the contact force to the bottom side shoulder 18 by the axial rolling element 60 is suppressed. Therefore, the induced thrust force due to the contact force is reduced.

  In the constant velocity joint 1, the rolling surface 16 is formed in parallel to the axis of the leg shaft 22, and the first tangent vector Vs 1 is closer to the bottom surface 12 a side than the opening side of the raceway groove 12. The opening-side shoulder 17 is formed so as to be further away. Thereby, when the axial rolling element 60 enters the rolling surface 16 from the opening side shoulder 17 side, the axial rolling element 60 is reliably guided to the rolling surface 16 side. Therefore, the contact force to the opening side shoulder 17 by the shaft-shaped rolling element 60 is reliably suppressed.

  In the constant velocity joint 1, the rolling surface 16 is formed parallel to the axis of the leg shaft 22, and the second tangent vector Vs2 is the axis of the leg shaft 22 on the opening side from the bottom surface 12 a side of the raceway groove 12. The bottom-side shoulder 18 is formed so as to be farther away. Thereby, when the axial rolling element 60 enters the rolling surface 16 from the bottom side shoulder 18 side, the axial rolling element 60 is reliably guided to the rolling surface 16 side. Therefore, the contact force to the bottom-side shoulder 18 by the shaft-like rolling element 60 is reliably suppressed.

  In the constant velocity joint 1, the opening-side shoulder 17 is positioned on the rolling surface 16 side, and the first regulating inclined surface 17 a that regulates the posture of the axial rolling element 60 that rolls on the rolling surface 16. The first regulating inclined surface 17b is located on the opening side of the raceway groove 12 with respect to the first regulating inclined surface 17a, has a first contact point Pb1, and has a first introduction inclined surface 17b having a smaller inclination than the first regulating inclined surface 17a.

  Since the opening-side shoulder 17 has the first introduction inclined surface 17b, the axial-shaped rolling element 60 rolls from the opening-side shoulder 17 side in a state where the axial-shaped rolling element 60 is inclined with respect to the raceway groove 12. When entering the surface 16, the shaft-shaped rolling element 60 contacts the first introduction inclined surface 17b having a small inclination. Therefore, the axial rolling element 60 is guided to the rolling surface 16 side. Therefore, the contact force to the opening-side shoulder 17 by the shaft-like rolling element 60 is reduced, and the induced thrust force due to the contact force is reduced. Moreover, when the opening-side shoulder portion 17 has the first restriction inclined surface 17a, the posture of the axial rolling element 60 is restricted when the axial rolling element 60 rolls on the rolling surface 16. That is, the posture of the rolling element unit 30 is reliably regulated.

  In the constant velocity joint 1, the bottom shoulder 18 is positioned on the rolling surface 16 side, and a second regulating inclined surface 18 a that regulates the posture of the axial rolling element 60 that rolls on the rolling surface 16. The second regulating inclined surface 18a is located on the bottom surface 12a side of the raceway groove 12, has a second contact point Pb2, and has a second introduction inclined surface 18b having a smaller inclination than the second regulating inclined surface 18a. .

  Since the bottom-side shoulder 18 has the second introduction inclined surface 18b, the axial-shaped rolling element 60 rolls from the bottom-side shoulder 18 side in a state where the axial-shaped rolling element 60 is inclined with respect to the raceway groove 12. When entering the surface 16, the shaft-like rolling element 60 contacts the second introduction inclined surface 18b having a small inclination. Therefore, the axial rolling element 60 is guided to the rolling surface 16 side. Accordingly, the contact force of the shaft-like rolling element 60 to the bottom side shoulder 18 is reduced, and the induced thrust force due to the contact force is reduced. Further, since the bottom shoulder 18 has the second regulating inclined surface 18a, the attitude of the axial rolling element 60 is regulated when the axial rolling element 60 rolls on the rolling surface 16. That is, the posture of the rolling element unit 30 is reliably regulated.

  Further, the first regulating inclined surface 17a and the first introduction inclined surface 17b are connected so that the contact surfaces are continuous. Here, when the shaft-like rolling element 60 passes from the first introduction inclined surface 17 b through the first regulating inclined surface 17 a and enters the rolling surface 16, the shaft-like rolling element 60 is in contact with the opening-side shoulder 17. It will be in a state of being pressed. However, as described above, the contact surface is a continuous connection, so that the axial rolling element 60 can enter the rolling surface 16 very smoothly.

  Moreover, the 2nd control inclination surface 18a and the 2nd introduction inclination surface 18b are connected so that a contact surface may become continuous. Here, when the axial rolling element 60 enters the rolling surface 16 from the second introduction inclined surface 18b through the second regulating inclined surface 18a, the axial rolling element 60 is in contact with the bottom shoulder 18. It will be in a state of being pressed. However, as described above, the contact surface is a continuous connection, so that the axial rolling element 60 can enter the rolling surface 16 very smoothly.

1: constant velocity joint, 10: outer joint member, 12: raceway groove, 12a: bottom surface, 12b: side surface, 16: rolling surface, 17: opening side shoulder, 17a: first regulating inclined surface, 17b: first Introducing inclined surface, 18: bottom side shoulder, 18a: second regulating inclined surface, 18b: second introducing inclined surface, 20: inner joint member, 22: leg shaft, 30: rolling element unit, 40: inner member, 60 : Axial rolling element 61: rolling part 61a: opening side end part 61b: bottom side end part Pa1: first regulation point Pa2: second regulation point Pb1: first contact point Pb2: first Two contact points, Vi1: first approach vector, Vi2: second approach vector, Vs1: first tangent vector, Vs2: second tangent vector, L: axial length of rolling part, W: width, θ1, θ2: eggplant Corner

Claims (10)

An outer joint member formed in a cylindrical shape and having a plurality of raceway grooves formed on the inner peripheral surface;
An inner joint member comprising a plurality of leg shafts projecting radially outward;
An inner member supported on the outer peripheral surface of the leg shaft;
A plurality of axial rolling elements that circulate along the outer periphery of the inner member and roll on the side surfaces of the raceway grooves and the outer peripheral surface of the inner member;
A constant velocity joint comprising:
The side surface of the raceway groove is a rolling surface having a width larger than the axial length of the rolling portion of the shaft-like rolling element, an opening side shoulder portion formed on the opening side of the raceway groove on the rolling surface, and A bottom surface side shoulder formed on the bottom surface side of the raceway groove of the rolling surface,
In the case where the shaft-shaped rolling element enters the rolling surface after the opening-side end of the shaft-shaped rolling element contacts the first contact point of the opening-side shoulder,
On the plane perpendicular to the axial direction of the outer joint member, a vector heading toward the first contact point in a path of the opening-side end entering the first contact point is defined as a first approach vector, and the track groove A vector from the opening side to the bottom side of the first contact point in the tangent of the side surface is defined as a first tangent vector,
The constant velocity joint in which the opening side shoulder is formed so that an angle formed by the first approach vector and the first tangent vector is an acute angle. In the case where the shaft-like rolling element enters the rolling surface after the bottom-side end of the shaft-like rolling element contacts the second contact point of the bottom-side shoulder,
On the plane perpendicular to the axial direction of the outer joint member, a vector toward the second contact point is defined as a second approach vector in a locus where the bottom surface side end part enters the second contact point, and the raceway groove A vector from the bottom surface side to the opening side of the second contact point in the tangent line of the side surface is defined as a second tangent vector,
The constant velocity joint according to claim 1, wherein the bottom shoulder is formed so that an angle formed by the second approach vector and the second tangent vector is an acute angle. The rolling surface is formed parallel to the axis of the leg shaft,
The opening-side shoulder portion is formed to be inclined so that the first tangent vector is farther from the opening side of the raceway groove toward the bottom surface than the axis of the leg shaft. Constant velocity joint. The rolling surface is formed parallel to the axis of the leg shaft,
3. The constant velocity according to claim 2, wherein the bottom-side shoulder is inclined so that the second tangent vector is farther from the bottom side of the raceway groove toward the opening side than the axis of the leg shaft. Joint. The opening side shoulder is
A first regulating inclined surface that is located on the rolling surface side and regulates the posture of the axial rolling element that rolls on the rolling surface;
A first introduction inclined surface located on the opening side of the raceway groove from the first regulating inclined surface, having the first contact point, and having a smaller inclination than the first regulating inclined surface;
The constant velocity joint as described in any one of Claims 1-4 provided with these. The bottom shoulder is
A second regulating inclined surface that is located on the rolling surface side and regulates the posture of the shaft-like rolling element rolling on the rolling surface;
A second introduction inclined surface located on the bottom surface side of the raceway groove from the second restricting inclined surface, having the second contact point, and having a smaller inclination than the second restricting inclined surface;
The constant velocity joint according to claim 2, comprising:   The constant velocity joint according to claim 5, wherein the first regulation inclined surface and the first introduction inclined surface are connected so that a contact surface is continuous.   The constant velocity joint according to claim 6, wherein the second regulating inclined surface and the second introduction inclined surface are connected so that a contact surface is continuous. An outer joint member formed in a cylindrical shape and having a plurality of raceway grooves formed on the inner peripheral surface;
An inner joint member comprising a plurality of leg shafts projecting radially outward;
An inner member supported on the outer peripheral surface of the leg shaft;
A plurality of axial rolling elements that circulate along the outer periphery of the inner member and roll on the side surfaces of the raceway grooves and the outer peripheral surface of the inner member;
A constant velocity joint comprising:
The side surface of the raceway groove is a rolling surface having a width larger than the axial length of the rolling portion of the shaft-like rolling element, an opening side shoulder portion formed on the opening side of the raceway groove on the rolling surface, and A bottom surface side shoulder formed on the bottom surface side of the raceway groove of the rolling surface,
In the case where the shaft-shaped rolling element enters the rolling surface after the opening-side end of the shaft-shaped rolling element contacts the first contact point of the opening-side shoulder,
The opening side shoulder is
A first regulating inclined surface that is located on the rolling surface side and regulates the posture of the axial rolling element that rolls on the rolling surface;
A first introduction inclined surface located on the opening side of the raceway groove from the first regulating inclined surface, having the first contact point, and having a smaller inclination than the first regulating inclined surface;
A constant velocity joint. In the case where the shaft-like rolling element enters the rolling surface after the bottom-side end of the shaft-like rolling element contacts the second contact point of the bottom-side shoulder,
The bottom shoulder is
A second regulating inclined surface that is located on the rolling surface side and regulates the posture of the shaft-like rolling element rolling on the rolling surface;
A second introduction inclined surface located on the bottom surface side of the raceway groove from the second restricting inclined surface, having the second contact point, and having a smaller inclination than the second restricting inclined surface;
The constant velocity joint according to claim 9, comprising:

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