JP6561564B2 - Constant velocity joint - Google Patents

Description

  The present invention relates to a slide type constant velocity joint that allows expansion and contraction in the direction of a rotation axis.

  As a slide type constant velocity joint, Patent Document 1 discloses a tripod type constant velocity joint. The constant velocity joint of Patent Document 1 is provided with a circulation type rolling element unit that is supported by three leg shafts provided on an inner joint member (tripod) and in which a plurality of rolling elements circulate around the outer periphery. In such a constant velocity joint, the rolling element unit is configured to be movable in the raceway groove of the outer joint member (outer ring), and as a whole, expansion and contraction in the rotational axis direction is allowed.

  Patent Document 2 discloses a constant velocity joint including a roller-type rolling element unit different from the circulation type. In the constant velocity joint of Patent Document 2, a protrusion (crimping) is provided near the opening of the outer joint member, and a roller-type rolling element unit (roller assembly) is prevented from coming off.

JP 2010-007701 A Japanese Patent Application Laid-Open No. 11-336782

  In a constant velocity joint including a circulation type rolling element unit, when restricting the axial movement of the rolling element unit for the purpose of preventing the rolling element unit from being detached, as in Patent Document 2, a protrusion is provided in the raceway groove. The structure to provide can be considered. However, when the circulation type rolling element unit comes into contact with the projection, the rolling element receives a load from the projection due to the contact, and the holding member that holds the rolling element in a circulatory manner may receive the load.

  This invention is made in view of such a situation, and provides the constant velocity joint which can reduce the load added to a holding member, restrict | limiting the movement beyond the movable range of a circulation type rolling element unit. With the goal.

(Claim 1) A constant velocity joint according to the present invention includes an outer joint member having an opening on one end side in the axial direction and including a plurality of raceway grooves extending in the axial direction, and a leg shaft inserted into the raceway groove. A plurality of inner joint members, and a plurality of rolling element units that are formed in an annular shape, are supported by each of the plurality of leg shafts so as to be tiltable, and roll on each of the plurality of raceway grooves. The rolling element unit includes an inner member having a power transmission surface facing the groove side surface of the raceway groove on an outer surface, and a groove side surface of the raceway groove between the groove side surface of the raceway groove and the power transmission surface. A plurality of rolling elements provided so as to be capable of rolling, and a holding member that holds the rolling elements so that the rolling elements can circulate around the outer periphery of the inner member.
The outer joint member is formed to project from the groove side surface of the raceway groove to the center side in the groove width direction of the raceway groove, and contacts the rolling element to push the rolling element into the inner peripheral side of the rolling element unit. Has a protrusion. The inner member includes an engaging portion that engages with the rolling element pushed in by the protruding portion and holds the rolling member in a state of being sandwiched between the protruding portion. The engaging portion is formed in a concave shape that is recessed toward the inner peripheral side of the rolling element unit, and is formed in an arc concave shape that is set to have a larger radius of curvature than the outer diameter of the rolling element.

  According to the first aspect of the present invention, when the rolling element unit moves in the axial direction to a position where the rolling element contacts the protrusion, the rolling element that contacts the protrusion engages with the engaging portion of the inner member. Therefore, movement along the circulation trajectory is restricted. As a result, the rolling element and the inner member are sandwiched between the protrusion and the leg shaft, and the axial movement of the rolling element unit relative to the outer joint member is restricted. Therefore, the movement beyond the movable range of the circulation type rolling element unit can be restricted. Moreover, since the rolling element and the inner member are interposed between the protrusion and the leg shaft, the load on the holding member that holds the rolling element can be reduced. Therefore, since increase in the required strength of the holding member can be suppressed, the holding member and the entire apparatus can be reduced in size.

It is a perspective view which shows the axial direction cross section of the outer joint member of the constant velocity joint in embodiment, and a partial cross section of a rolling element unit. It is a perspective view which shows a tripod and the rolling element unit from which the inner member was isolate | separated. It is a figure which shows the cross section of an outer joint member, and the upper surface of a rolling element unit. It is an enlarged view which shows the state which the rolling element contacted the projection part, seeing through a holding member. It is an enlarged view which shows the state in which the axial direction movement of a rolling element unit is controlled, seeing through a holding member.

<Embodiment>
(Overall configuration of constant velocity joint)
The constant velocity joint 1 of the present invention will be described with reference to FIGS. Here, the constant velocity joint 1 of this embodiment is used, for example, for a power transmission shaft of a vehicle. The power transmission shaft is used at a connection portion between a differential gear (not shown) and a wheel (not shown).

  As shown in FIG. 1, the constant velocity joint 1 includes an outer ring 10 (corresponding to the “outer joint member” of the present invention), a tripod 20 (corresponding to the “inner joint member” of the present invention), and three rolling joints. And a moving body unit 30. FIG. 1 shows the constant velocity joint 1 in which the angle formed by the rotation axis of the shaft 2 and the rotation axis of the outer ring 10 (joint angle of the constant velocity joint 1) is 0 °.

  The outer ring 10 is formed in a cylindrical shape (in the present embodiment, a bottomed cylindrical shape) having an opening 11 on one axial end side. The bottom outer side of the outer ring 10 is connected to a differential. A plurality of raceway grooves 12 extending in the axial direction (left-right direction in FIG. 1) from the opening 11 are formed at equal intervals in the circumferential direction on the inner peripheral surface of the cylindrical portion of the outer ring 10.

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

  Further, the outer ring 10 has a plurality of first protrusions 13 and a plurality of second protrusions 14. The first protrusion 13 and the second protrusion 14 constitute a restriction mechanism that restricts the movement of the rolling element unit 30 beyond the movable range. The first protrusion 13 and the second protrusion 14 are arranged at different axial positions (left and right positions in FIG. 3) from the groove side surface 12b of the track groove 12 in the groove width direction (vertical direction in FIG. 3). ) Projecting to the center side. The first protrusion 13 and the second protrusion 14 are portions of the outer ring 10 that come into contact with the rolling element 60 of the rolling element unit 30 described later and push the rolling element 60 into the inner peripheral side of the rolling element unit 30.

  The plurality of first protrusions 13 are formed in pairs so as to protrude from the groove side surfaces 12b on both sides of the raceway groove 12 at the axial position where the opening 11 of the outer ring 10 is formed. On the other hand, the plurality of second protrusions 14 are formed in pairs so as to protrude from the groove side surfaces 12b on both sides of the raceway groove 12 at the axial position where the bottom of the outer ring 10 is formed. In the present embodiment, the first projecting portion 13 and the second projecting portion 14 each have a slope portion inclined with respect to the groove extending direction of the raceway groove 12.

  The plurality of first protrusions 13 are formed by processing the caulking or the like on the opening 11 after the rolling element unit 30 is inserted into the raceway groove 12, and another member is fixed to the opening 11. Formed. In addition to being formed simultaneously with the formation of the outer ring 10, the plurality of second protrusions 14 are formed by fixing another member to the bottom of the outer ring 10. The operation of the first protrusion 13 and the second protrusion 14 will be described in the description of the movement restricting mechanism of the rolling element unit 30.

  The tripod 20 is disposed inside the outer ring 10. The tripod 20 can move with respect to the outer ring 10 in the axial direction of the outer ring 10 and can tilt. As shown in FIG. 2, the tripod 20 includes a boss 21 formed in an annular shape and three leg shafts 22 extending radially outward from the boss 21. The boss 21 is integrally connected to the shaft 2 on the inner peripheral side.

  Each of the leg shafts 22 includes a tip portion whose outer peripheral surface is formed in a spherical convex shape, and a root portion that connects the tip portion to the boss 21. The cross-sectional shape in the axial direction (extending direction of the leg shaft 22) at the distal end portion of the leg shaft 22 has a circular arc shape. Further, the distal end portion of the leg shaft 22 is inserted into the raceway groove 12 of the outer ring 10.

  The rolling element unit 30 is formed in an annular shape as a whole. In the present embodiment, the rolling element unit 30 is formed in a rectangular shape. The rolling element unit 30 is supported so as to be tiltable to the outer peripheral side of the tip end portion of the leg shaft 22 and tiltable with respect to the axis of the leg shaft 22. As shown in FIG. 3, the rolling element unit 30 is disposed in the raceway groove 12 so as to be movable along the raceway groove 12 of the outer ring 10. The rolling element unit 30 is interposed between the raceway groove 12 and the leg shaft 22 of the outer ring 10, and is configured to be able to transmit torque between both members.

(Detailed configuration of the rolling element unit 30)
As shown in FIGS. 2 and 3, the rolling element unit 30 includes an inner member 40, a plurality of rolling elements 60, and a holding member 70, and adopts a circulation type. The inner member 40 is formed in an annular shape as a whole. 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 between the leg shaft 22, and enables power transmission between the leg shaft 22 and the rolling element unit 30. The inner member 40 has a power transmission surface 54 facing the groove side surface 12b of the raceway groove 12 on the outer surface.

  The rolling element 60 is provided between the groove side surface 12 b of the raceway groove 12 and the power transmission surface 54 of the inner member 40 so as to roll along the groove side surface 12 b of the raceway groove 12. In this embodiment, the rolling element 60 is a needle formed in an axial shape. The rolling element 60 includes a main body portion 61 having a cylindrical outer peripheral surface and a small diameter portion 62 protruding in the axial direction from both ends of the main body portion (see FIG. 1).

  The holding member 70 holds the plurality of rolling elements 60 such that the plurality of rolling elements 60 can circulate around the outer periphery of the inner member 40. As shown in FIG. 3, the holding member 70 is formed in an annular shape as a whole and has a shape surrounding the outer periphery of the inner member 40. The holding member 70 includes a pair of circulation path forming members that form a circulation path of the rolling element 60. The pair of circulation path forming members are integrally connected by caulking the respective connecting portions 72 with the rail portions 71 facing each other in the axial direction (vertical direction in FIG. 2).

  A pair of rail parts 71 hold | maintain so that the small diameter part 62 located in the axial direction both ends of the rolling element 60 may be covered. As a result, the holding member 70 restricts the axial movement of the rolling element 60 and enables the rolling element 60 to circulate along the circulation path. In addition, the holding member 70 is formed with a pair of inner peripheral surfaces 73 that are opposed to each other in the axial direction of the outer ring 10 by two sets of connected connecting portions 72. In the present embodiment, each of the pair of inner peripheral surfaces 73 is formed in a planar shape that is parallel to the axial direction of the holding member 70 and orthogonal to the axial direction of the outer ring 10.

(Detailed configuration of the inner member 40)
In this embodiment, the inner member 40 includes a pair of first divided members 41 and second divided members 42 that are divided in the groove width direction of the raceway grooves 12 of the outer ring 10. The first divided member 41 and the second divided member 42 have shapes that are plane-symmetric with respect to a plane that includes the rotation axis of the tripod 20 and the central axis of the leg shaft 22.

  The first divided member 41 and the second divided member 42 are independent members, and are arranged so as to sandwich the leg shaft 22 from both sides in the groove width direction of the raceway groove 12 as shown in FIGS. The Since the 1st division member 41 and the 2nd division member 42 are comprised by the plane symmetrical shape as mentioned above, below, the detailed shape of one 1st division member 41 is demonstrated.

  The first divided member 41 is formed in a U-shaped block shape when viewed from the axial direction of the inner member 40 (front-rear direction in FIG. 3). The inner side surface 51 that faces the outer peripheral surface of the leg shaft 22 among the side peripheral surfaces of the first split member 41 is the tip of the leg shaft 22 in a state where the first split member 41 is disposed on the outer peripheral side of the leg shaft 22. Contact with the outer peripheral surface of the slab so that power can be transmitted.

  Further, the first split member 41 is engaged with the rolling elements 60 at both ends adjacent to the power transmission surface 54 on the outer surface of the inner member 40 formed in an annular shape (the side peripheral surface of the first split member 41). It has a joint part 55. These engaging portions 55 constitute a movement restricting mechanism for the rolling element unit 30. When the rolling element unit 30 moves in the axial direction of the outer ring 10 to the position where the rolling element 60 comes into contact with the first protruding part 13 (or the second protruding part 14), the engaging part 55 (the first protruding part 13 ( Or it engages with the rolling element 60 pushed into the inner peripheral side of the rolling element unit 30 by contact with the second protrusion 14) (see FIG. 5).

  In this embodiment, the engaging portion 55 is formed in a concave shape that is recessed toward the inner peripheral side of the rolling element unit 30. Further, the engaging portion 55 is formed in an arcuate concave shape set to have a larger curvature radius than the outer diameter of the rolling element 60 (the outer diameter of the main body portion 61 that transmits power). That is, the curvature radius R2 in the engagement portion 55 is set larger than the curvature radius R1 of the main body portion 61 of the rolling element 60 (R1 <R2). Thereby, when the rolling element 60 and the engaging part 55 are engaged in the axial direction, the concave curved surface of the engaging part 55 can come into line contact with the outer surface of the rolling element 60.

  The inner member 40 constituted by the first divided member 41 and the second divided member 42 as a whole is formed in a symmetrical shape in the groove width direction and the groove extending direction of the raceway groove 12. In other words, the inner member 40 is formed in the same shape as the one engaging portion 55 at a position symmetrical with respect to the one engaging portion 55 with the leg shaft 22 as the center. As a result, the inner member 40 is arranged such that the side ends located at both ends in the axial direction of the outer ring 10 have no directionality, and each side end is replaced with either the opening 11 side or the bottom side of the outer ring 10. Allow to be done.

  Further, the inner member 40 has a plurality of engaging portions 55 respectively corresponding to the pair of first protrusions 13 and the pair of second protrusions 14 provided at predetermined axial positions of the outer ring 10. As a result, when the rolling elements 60 come into contact with the pair of first protrusions 13 (or the pair of second protrusions 14), the rolling elements 60 are connected to the plurality of inner members 40 by the contact. It is comprised so that it may each engage with the engaging part 55 of this.

(Movement restriction mechanism of rolling element unit 30)
As described above, the constant velocity joint 1 includes the pair of first protrusions 13, the pair of second protrusions 14, and the plurality of engagement portions 55 formed on the inner member 40. Is configured. The movement restricting mechanism of the rolling element unit 30 prevents the rolling element unit 30 inserted into the raceway groove 12 of the outer ring 10 from coming out of the opening 11 of the outer ring 10 or coming into contact with the bottom of the outer ring 10. It is provided as a purpose.

  The movement restricting mechanism of the rolling element unit 30 acts to restrict the movement when the rolling element unit 30 attempts to move in the groove extending direction beyond the movable range. Specifically, when the rolling element unit 30 moves, for example, to one side (opening 11 side) in the groove extending direction of the outer ring 10, as shown in FIG. The nearest rolling element 60 contacts.

  Further, when the rolling element unit 30 moves to one side in the groove extending direction, the rolling element 60 receives a reaction force from the first protrusion 13 due to the contact with the first protrusion 13 as shown in FIG. It is pushed into the inner peripheral side of the moving body unit 30. At this time, the direction in which the rolling element 60 is pushed and moves relative to the inner member 40 does not coincide with the circulation locus Tc of the rolling element 60. However, relative movement of the rolling element 60 is allowed due to the dimensional relationship between the small diameter part 62 of the rolling element 60 and the rail part 71 of the holding member 70 or the elastic deformation of the rail part 71.

  The engaging portion 55 of the inner member 40 engages with the rolling element 60 pushed into the inner peripheral side of the rolling element unit 30. More specifically, the rolling element 60 makes line contact with the curved surface of the engaging portion 55 formed of a circular arc concave shape set to have a radius of curvature R2 larger than the outer diameter of the rolling element 60. Thereby, the rolling element 60 is hold | maintained in the state inserted | pinched between the 1st projection part 13 and the inner side member 40, and the movement along the circulation locus | trajectory Tc is controlled.

  Here, the first divided member 41 side of the inner member 40 has been described, but the same applies to the second divided member 42 side (lower side in FIG. 3). That is, the rolling element 60 in contact with the first protrusion 13 is held in a state of being sandwiched between the engagement portion 55 formed on the second split member 42 and the first protrusion 13. At this time, of the plurality of rolling elements 60, the rolling elements 60 positioned on the bottom side of the outer ring 10 with respect to the two rolling elements 60 sandwiched between the pair of first protrusions 13 and the inner member 40 are the 2 Without being loaded from the two rolling elements 60, the state of being held on the circulation locus Tc by the rail portion 71 is maintained.

  When the rolling element unit 30 receives a load from the leg shaft 22 of the tripod 20 and is moved in the groove extending direction, the rolling element 60 and the inner member 40 are interposed between the first protrusion 13 and the leg shaft 22. It will be in the state where it was pinched. Thereby, the axial movement beyond the movable range of the rolling element unit 30 with respect to the outer ring 10 is restricted, and the rolling element unit 30 assembled to the outer ring 10 is prevented from coming off.

  The same applies when the rolling element unit 30 moves to the other side (bottom side) of the outer ring 10 in the groove extending direction. That is, the two rolling elements 60 that are in contact with the pair of second projecting portions 14 are held in a state of being sandwiched between the engaging portion 55 of the inner member 40 and the second projecting portion 14. Thereby, the axial movement exceeding the movable range of the rolling element unit 30 with respect to the outer ring 10 is restricted, and the contact of the rolling element unit 30 with the bottom of the outer ring 10 is prevented.

<Effects of Configuration of Embodiment>
In the embodiment, the inner member 40 has the first protrusion 13 when the rolling element unit 30 moves in the axial direction of the outer ring 10 to a position where the rolling element 60 contacts the first protrusion 13 or the second protrusion 14. Or it engages with the rolling element 60 pushed into the inner peripheral side of the rolling element unit 30 by the second protrusion 14 and sandwiches the rolling element 60 between the first protrusion 13 or the second protrusion 14. It has the engaging part 55 hold | maintained in a state.

  According to such a configuration, when the rolling element unit 30 moves in the axial direction to a position where the rolling element 60 contacts the first protruding part 13 (second protruding part 14), the first protruding part 13 (second protruding part) 14) is brought into contact with the engaging portion 55 by being pushed into the inner peripheral side of the rolling element unit 30. Thereby, the said rolling element 60 is hold | maintained in the state pinched | interposed between the 1st projection part 13 (2nd projection part 14) and the engaging part 55, and the movement of the rolling element 60 along the circulation locus | trajectory Tc is controlled. Is done. As a result, the rolling element 60 and the inner member 40 are sandwiched between the first protrusion 13 (second protrusion 14) and the leg shaft 22, and the axial movement of the rolling element unit 30 with respect to the outer ring 10 is restricted. Is done.

  Therefore, by appropriately arranging the first protrusion 13 (second protrusion 14) on the outer ring 10 at a position corresponding to the movable range of the rolling element unit 30, the movement exceeding the movable range of the circulating rolling element unit 30 can be achieved. Can be regulated. Moreover, between the 1st projection part 13 (2nd projection part 14) and the leg axis | shaft 22, the rolling element 60 and the inner side member 40 intervene, and a load is transmitted. Thereby, the load applied to the holding member 70 holding the plurality of rolling elements 60 can be reduced. Therefore, since the increase in strength required for the holding member 70 can be suppressed, the size of the holding member 70 and the entire apparatus can be reduced.

Further, the engaging portion 55 is formed in a concave shape that is recessed toward the inner peripheral side of the rolling element unit 30.
According to such a configuration, the rolling element 60 in contact with the first protrusion 13 (second protrusion 14) is reliably engaged in the axial direction by the concave engaging portion 55 and follows the circulation locus. Movement is restricted. Therefore, the movement beyond the movable range of the circulation type rolling element unit 30 can be controlled.

Further, the engaging portion 55 is formed in an arcuate concave shape set to a radius of curvature R2 larger than the outer diameter of the rolling element 60.
According to such a configuration, when the rolling element 60 and the engaging portion 55 of the inner member 40 are engaged in the axial direction, the curved surface having the concave shape of the engaging portion 55 contacts the outer surface of the rolling element 60. Thereby, in the state where movement of rolling element unit 30 is controlled, it is prevented that a local load is applied to rolling element 60. Further, the rolling element 60 is recessed to the engagement position after the rolling element 60 comes into contact with the first protrusion 13 (second protrusion 14) and moves relative to the position where it engages with the engagement part 55. Guided to a curved surface of shape.

In addition, the inner member 40 is formed in the same shape as the engaging portion 55 at a position symmetrical to the engaging portion 55 with the leg shaft 22 as the center.
According to such a configuration, the inner member 40 has a symmetrical shape with the center portion into which the leg shaft 22 is inserted as the center. Thereby, the incorrect assembly | attachment at the time of arrange | positioning the inner member 40 to the inner peripheral side of the holding member 70 is prevented. Further, the rolling element unit 30 as a whole has a symmetrical shape with the leg shaft 22 as the center, thereby preventing erroneous assembly when the rolling element unit 30 is inserted into the raceway groove 12 of the outer ring 10. As described above, the above-described configuration can improve the assembling property of the constant velocity joint 1.

Further, the outer ring 10 has a plurality of first protrusions 13 and a plurality of second protrusions 14 that protrude from the groove side surfaces on both sides of the raceway groove 12 at a predetermined axial position. The inner member 40 has a plurality of engaging portions 55 corresponding to the plurality of first protruding portions 13 and the plurality of second protruding portions 14.
According to such a configuration, in the rolling element unit 30, the rolling elements 60 come into contact with the plurality of first protrusions 13 (second protrusions 14), respectively, and each rolling element 60 is engaged with the inner member 40 by the contact. Engage with the mating portion 55. Thereby, compared with the structure by which the 1st projection part 13 (2nd projection part 14) is provided only in the one side of the track groove 12, the movement beyond the movable range of the rolling element unit 30 can be controlled more reliably. Moreover, since the load applied to the rolling element unit 30 is distributed, the load of each member is reduced.

The outer ring 10 has a plurality of first protrusions 13 and a plurality of second protrusions 14 that protrude from the groove side surfaces of the raceway grooves 12 at different axial positions. The inner member 40 has a plurality of engaging portions 55 corresponding to the plurality of first protruding portions 13 and the plurality of second protruding portions 14.
According to such a configuration, the rolling element unit 30 is prevented from coming off by the first protrusion 13 on the opening 11 side of the outer ring 10. The rolling element unit 30 is prevented from colliding with the bottom by the second protrusion 14 on the bottom side of the outer ring 10.

<Modification of Embodiment>
(About the engaging portion 55)
In the embodiment, the engaging portion 55 is formed in a circular arc concave shape set to a radius of curvature larger than the outer diameter of the rolling element 60. On the other hand, the circular arc concave shape of the engaging portion 55 may be set to a radius of curvature equal to or less than the outer diameter of the rolling element 60 (R1 ≧ R2). In such a configuration, the rolling element 60 contacts and engages with the arc-shaped concave edge portion of the engaging portion 55. For example, according to the shape of the protrusions (first protrusion 13 and second protrusion 14), the radius of curvature of the arc-shaped concave shape of the engaging portion 55 may be appropriately set as described above. However, from the viewpoint of preventing a local load from being applied to the rolling element 60, the embodiment exemplified in the embodiment is preferable.

  Further, the concave shape of the engaging portion 55 may be configured to be stepped when viewed from the axial direction of the leg shaft 22 in addition to the circular arc concave shape. For example, the engaging portion 55 is formed in a step shape having a plurality of steps corresponding to various positions of the rolling element 60 on the circulation locus Tc. Thereby, the moving amount | distance of the rolling element 60 pushed into the inner peripheral side of the rolling element unit 30 can be made small. Therefore, when the axial movement of the rolling element unit 30 is restricted, the influence on the rolling element 60 adjacent to the rolling element 60 that contacts the protrusion can be reduced.

(About the first protrusion 13 and the second protrusion 14)
In the embodiment, the outer ring 10 has a pair of first protrusions 13 and a pair of second protrusions 14. On the other hand, the constant velocity joint 1 is either the first protrusion 13 or the second protrusion 14 depending on the use for preventing the rolling element unit 30 from coming off or preventing the outer ring 10 from colliding with the bottom. It is good also as a structure provided only with one side.

  In such a configuration, for example, when a protrusion is provided only on the opening 11 side of the outer ring 10, the engaging portion 55 formed on the bottom side of the outer ring 10 in the inner member 40 moves the rolling element unit 30. It does not function as a regulatory mechanism. However, since the inner member 40 is formed in a symmetrical shape around the leg shaft 22 by the engaging portion 55 on the bottom side, an increase in the number of component types can be prevented.

  Further, when the rolling element unit 30 is inverted and inserted into the raceway groove 12 of the outer ring 10, the engaging portion 55 is located on the opening 11 side of the outer ring 10 and can be engaged with the rolling element 60. It functions as a movement restricting mechanism for the rolling element unit 30. In addition, since the rolling element unit 30 is configured in a shape that does not have directionality including the inner member 40, erroneous assembly of the rolling element unit 30 to the outer ring 10 can be prevented.

  In the embodiment, the first protrusion 13 and the second protrusion 14 are formed in a pair so as to protrude from the groove side surfaces 12b on both sides of the raceway groove 12, respectively. On the other hand, the outer ring 10 may be configured to have one first protrusion 13 or one second protrusion 14 only on one side of the groove side surfaces 12b on both sides of the raceway groove 12. According to such a configuration, for example, in a state where the rolling element 60 comes into contact with the first protrusion 13 and is sandwiched and held between the first protrusion 13 and the engaging portion 55, the rolling element unit 30 is It is pressed against the groove side surface 12b opposite to the first protrusion 13 in the groove width direction of the raceway groove 12, and the axial movement is restricted.

  Further, the first protrusion 13 and the second protrusion 14 each have an inclined surface inclined with respect to the groove extending direction of the raceway groove 12. On the other hand, the shape of the site | part which contacts the rolling element 60 is suitably set for the 1st projection part 13 and the 2nd projection part 14. FIG. For example, in consideration of the shape of the rolling element 60 in the rolling element unit 30, the circulation trajectory Tc, the contact position with respect to the circulation trajectory Tc, and the like, the contact portion may be an angle or a shape of the slope (arc, step, convex, Concave). Thereby, the rolling element 60 which contacted the 1st projection part 13 and the 2nd projection part 14 is suitably pushed in to the inner peripheral side of the rolling element unit 30, and is engaged with the engaging part 55. FIG.

(Type of rolling element unit 30)
In the embodiment, the inner member 40 of the rolling element unit 30 is configured by a first divided member 41 and a second divided member 42 that are made of different members. On the other hand, the inner member 40 may be configured by a single member in which these divided members are integrally formed. Even in such a type of rolling element unit 30, the same effect can be obtained by applying the same configuration as the embodiment.

  In the embodiment, the rolling element 60 of the rolling element unit 30 is a needle formed in an axial shape. On the other hand, in the rolling element 60, the shape of the main body portion 61 may be a barrel shape in addition to the cylindrical shape, or may be a sphere other than the needle. Even in such a type of rolling element unit 30, the same effect can be obtained by applying the same configuration as the embodiment.

(Constant velocity joint type)
In the embodiment, the number of the raceway grooves 12 of the outer joint member (outer ring 10), the leg shaft 22 of the inner joint member (tripod 20), and the rolling element unit 30 are all three. On the other hand, the inner joint member may include a plurality of (for example, two) leg shafts arranged at equal intervals in the circumferential direction. Along with this, a plurality of raceway grooves 12 into which the leg shafts are inserted are formed in the outer joint member, and a plurality of rolling element units 30 are arranged between the leg shafts and the raceway grooves 12. Even with this type of constant velocity joint, the same effect can be obtained by applying the present invention.

  1: constant velocity joint, 10: outer ring (outer joint member), 11: opening, 12: raceway groove, 12b: groove side surface, 13: first projection (projection), 14: second projection (projection) ), 20: tripod (inner joint member), 22: leg shaft, 30: rolling element unit, 40: inner member, 54: power transmission surface, 55: engagement portion, 60: rolling element, 70: holding member, R1 : Radius of curvature (of rolling element), R2: radius of curvature (of engaging part)

Claims (4)

An outer joint member having an opening on one end side in the axial direction and including a plurality of track grooves extending in the axial direction;
An inner joint member comprising a plurality of leg shafts inserted into the raceway grooves;
A constant velocity joint comprising a plurality of rolling element units formed in an annular shape, supported to be tiltable on each of the plurality of leg shafts, and rolling on each of the plurality of raceway grooves,
The rolling element unit is
An inner member having a power transmission surface facing the groove side surface of the raceway groove on the outer surface;
A plurality of rolling elements provided between the groove side surface of the raceway groove and the power transmission surface so as to be rollable along the groove side surface of the raceway groove;
A holding member that holds the rolling element such that the rolling element can circulate around the outer periphery of the inner member;
The outer joint member is formed to project from the groove side surface of the raceway groove to the center side in the groove width direction of the raceway groove, and contacts the rolling element to push the rolling element into the inner peripheral side of the rolling element unit. Having a protrusion,
Said inner member, said engaging and said rolling elements is pushed by the protrusion, it has a engaging portion for holding the rolling elements in a state sandwiched between the protrusion,
The engagement portion is formed in a concave shape that is recessed toward the inner peripheral side of the rolling element unit, and is formed in a circular arc concave shape that is set to have a larger radius of curvature than the outer diameter of the rolling element . 2. The constant velocity joint according to claim 1, wherein the inner member is formed in a portion having a symmetrical position with respect to the engaging portion about the leg axis in the same shape as the engaging portion. The outer joint member has a plurality of protrusions that protrude from the groove side surfaces on both sides of the raceway groove at a predetermined axial position, respectively.
The inner member has a plurality of the engagement portions corresponding to the plurality of the protrusions, constant velocity joint according to claim 1 or 2. The outer joint member has a plurality of the protruding portions that respectively protrude from the groove side surfaces of the raceway groove at different axial positions,
The constant velocity joint according to any one of claims 1 to 3 , wherein the inner member includes a plurality of the engaging portions corresponding to the plurality of projecting portions.

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