JP5083067B2 - Sliding tripod type constant velocity joint - Google Patents

Description

  The present invention relates to a sliding tripod type constant velocity joint.

Conventionally, as a sliding tripod type constant velocity joint, for example, there are those described in Japanese Patent No. 2766624 (Patent Document 1) and Japanese Patent No. 336196 (Patent Document 2). The roller unit constituting the sliding tripod type constant velocity joint described in Patent Literatures 1 and 2 includes an intermediate member on the outer periphery of the tripod shaft portion and a needle provided to be able to circulate the outer peripheral surface of the intermediate member. Yes. The needle is configured to roll along the intermediate member and the side surface of the raceway groove of the outer ring.
Japanese Patent No. 2763624 Japanese Patent No. 3361096

  By the way, when transporting the sliding tripod type constant velocity joint for mounting on a vehicle, the joint angle becomes larger than the joint angle when mounting on the vehicle. Therefore, at the time of conveyance, the shaft and the roller unit may come into contact with each other and the roller unit may be damaged. Therefore, it is necessary to regulate the joint angle so that the shaft and the roller unit do not come into contact with each other during conveyance of the constant velocity joint.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a sliding tripod type constant velocity joint capable of regulating the joint angle.

  Hereinafter, each means suitable for solving the above-described problems will be described with additional effects and the like as necessary.

(Means 1) The sliding tripod type constant velocity joint according to means 1 is
An outer ring having a cylindrical shape and formed with three raceway grooves extending in the outer ring rotation axis direction on the inner peripheral surface;
A boss portion coupled to the shaft, and three tripod shaft portions that are erected so as to extend radially outward of the boss portion from the outer peripheral surface of the boss portion and are inserted into the raceway grooves, respectively. Tripod,
Side opposite to the axial direction cross-sectional shape of the raceway grooves have a power transmission surface formed of circularly arcuate concave outer surface, arranged from both sides of the track groove so as to sandwich the tripod shaft part, and the tripod shaft A pair of intermediate members provided to be swingable with respect to the portion ;
A plurality of rolling elements which are spherical or barrel-shaped rollers provided so as to be able to roll along the side surface of the raceway groove between the side surface of the raceway groove and the power transmission surface;
A cage that supports the rolling elements such that the rolling elements can circulate around the outer periphery of the pair of intermediate members;
A sliding tripod type constant velocity joint comprising:
The outer peripheral surface of the tripod shaft portion is spherically convex.
The inner surfaces of the pair of intermediate members are spherical concave shapes fitted to the outer peripheral surface of the tripod shaft part,
The pair of intermediate members move with the reciprocating motion of the tripod shaft portion with respect to the raceway groove when the tripod shaft portion reciprocates with respect to the raceway groove in the radial direction of the outer ring,
A posture in which the outer ring rotation axis and the rotation axis of the shaft coincide with each other is defined as a reference posture,
In the reference posture, the pair of intermediate members is set so as not to contact the base portion of the boss portion and the tripod shaft portion,
When the shaft is tilted with respect to the outer ring rotation shaft so as to add a joint angle from the state of the reference posture, at least one of the intermediate members is located at the root portion of the boss portion or the tripod shaft portion. The joint angle is regulated by contact.

Here, when the sliding tripod constant velocity joint is configured as described above, the cage is positioned on the outer peripheral side of the roller unit. The “roller unit” includes a member that transmits power between the tripod shaft and the raceway groove of the outer ring, and includes a pair of intermediate members, rolling elements, and a cage. The pair of intermediate members and rolling elements are members that perform power transmission. However, the cage is not necessarily an essential member for power transmission, and only needs to support the rolling elements. Such a cage is not a member that requires a very high strength. In particular, in order to satisfy demands for weight reduction and cost reduction, a structure or material that does not have high strength may be used by minimizing the strength of the cage. In such a case, if the shaft contacts the cage, the cage may be damaged. However, according to the means 1, when the tripod shaft part reciprocates in the radial direction of the outer ring with respect to the raceway groove, the intermediate member moves with the reciprocation of the tripod shaft part with respect to the raceway groove. Thereby, a pair of intermediate members are contacting the boss | hub part or the base part of a tripod shaft part, and are restricting a joint angle. Thereby, breakage of the cage can be prevented during conveyance.

(Means 2) In the sliding tripod type constant velocity joint of means 1,
When the shaft is tilted, the shaft and all the cages are not in contact with at least one of the intermediate members in contact with the boss portion or the base portion of the tripod shaft portion. Good.

  According to the means 2, since the shaft is not in contact with the cage when the joint angle is regulated, the cage can be reliably prevented from being damaged.

(Means 3) In the sliding tripod type constant velocity joint of means 2,
When the shaft is tilted to the phase in the central axis direction of any of the tripod shafts in the state of the reference posture, at least one of the intermediate members is the root of the boss part or the tripod shaft part Touch the part,
In a state where the intermediate member and the base portion of the boss portion or the tripod shaft portion are in contact with each other, the shaft and all the cages may not be in contact with each other.

  Here, the phase in the central axis direction of any tripod shaft portion in the state of the reference posture will be described below. First, the phase refers to the direction in which the shaft is tilted. That is, it indicates the direction of tilting of the shaft relative to the outer ring when the shaft is tilted with respect to the outer ring from the reference posture state. In the reference posture state, the center axis direction of the tripod shaft portion is centered on the shaft rotation axis of the reference posture, and the center axes of the three tripod shaft portions are spaced 120 degrees apart from each other in the circumferential direction of the outer ring. positioned. That is, the phase in the central axis direction of the tripod shaft portion in the reference posture is a phase in which the central axis of the tripod shaft portion extends when viewed from the outer ring rotation axis direction. That is, the phase has three locations.

  When the shaft is tilted to the phase in the central axis direction of the tripod shaft portion, the tripod shaft portion positioned in the phase moves most inward in the radial direction of the outer ring. Since the intermediate member moves with the reciprocating motion of the tripod shaft portion with respect to the raceway groove, the intermediate member also moves the largest inward in the radial direction of the outer ring, similarly to the tripod shaft portion. Further, the tripod swings with respect to the intermediate member and the outer ring. Therefore, the intermediate member is in a state of being closest to the boss portion or the root portion of the tripod shaft portion. In the present invention, at least in the phase, the intermediate member and the boss portion or the base portion of the tripod shaft portion are set in contact with each other. Thereby, in the said phase, the restriction | limiting effect of the joint angle by this invention can be exhibited reliably.

(Means 4) In the sliding tripod type constant velocity joint of any one of means 1 to 3,
The side surface of the raceway groove may have a concave groove that follows the spherical convex outer peripheral surface of the rolling element .

According to such a configuration, the concave groove on the side surface of the raceway groove has an arc shape in the radial cross section of the outer ring. Thereby, the rolling element which is a spherical shape or a barrel-shaped roller can be positioned with respect to the radial direction of the outer ring.

( Means 5 ) In the sliding tripod type constant velocity joint of any one of means 1 to 4 ,
The regulated joint angle may be set to be larger than the joint angle when the sliding tripod constant velocity joint is mounted on a vehicle.

According to the means 5 , it is possible to prevent the intermediate member from contacting the boss portion or the base portion of the tripod shaft portion when the vehicle is mounted. Accordingly, it is possible to prevent an adverse effect when the vehicle travels.

  Hereinafter, an embodiment in which a sliding tripod type constant velocity joint of the present invention (hereinafter simply referred to as “constant velocity joint”) is embodied will be described with reference to the drawings. Here, the case where the constant velocity joint of this embodiment is used for connection of a power transmission shaft of a vehicle will be described as an example. For example, it is a case where it uses for the connection part of the axial part connected with the differential gear, and the intermediate shaft of a drive shaft.

  The constant velocity joint 1 of this embodiment is demonstrated with reference to FIGS. FIG. 1 is a view seen from the opening side of the outer ring 10 in a partly assembled state of the constant velocity joint 1 of the present embodiment. FIG. 2 is a radial sectional view of a part of the constant velocity joint 1. FIG. 3 is a perspective view of the roller unit 30. 4A is a plan view of the roller unit 30, FIG. 4B is a view of the roller unit 30 in the direction A, and FIG. 4C is a view of the roller unit 30 in the direction B. FIG. FIG. 5 is a perspective view of one of the pair of intermediate members 40. 6 (a) is a front view of the intermediate member 40, and FIG. 6 (b) is a cross-sectional view of the intermediate member 40 taken along the line CC (including a partial cross section on the long diameter side). These are the D direction arrow views of the intermediate member 40. FIG. FIG. 7 is a perspective view of the cage 60. 8A is a plan view of the cage 60, FIG. 8B is a view taken in the direction of the arrow E of the cage 60, and FIG. It is a figure (figure including the partial cross section by the side of a long diameter).

  As shown in FIGS. 1 and 2, the constant velocity joint 1 includes an outer ring 10, a tripod 20, and a roller unit 30.

  The outer ring 10 is formed in a cylindrical shape (for example, a bottomed cylindrical shape), and one end side is connected to a differential gear (not shown). Three track grooves 11 extending in the outer ring axial direction (front-rear direction in FIG. 1) are formed on the inner peripheral surface of the cylindrical portion of the outer ring 10 at equal intervals in the circumferential direction of the outer ring shaft. The cross-sectional shape orthogonal to the groove extending direction in each raceway groove 11 is substantially U-shaped. In other words, each track groove 11 includes a groove bottom surface formed in a curved surface whose radial cross-sectional shape is an arc, and a side surface formed in a planar shape intersecting the groove bottom surface and facing each other in parallel. The side surface is provided with a concave groove that follows the spherical surface of the rolling element 50 so that the rolling element 50 made of a spherical body is positioned with respect to the radial direction of the outer ring 10. That is, in the concave groove on the side surface of the raceway groove 11, the radial cross-sectional shape of the outer ring 10 is an arc shape.

  Further, locking projections 12 for narrowing the opening width of the track groove 11 are formed on both opening edges of the track groove 11. The locking protrusion 12 is for restricting the position of a retainer 60 constituting a roller unit 30 described later. That is, the retainer 60 is always positioned inside the raceway groove 11 by the locking projection 12.

  The tripod 20 is disposed inside the cylindrical portion of the outer ring 10. The tripod 20 includes a boss portion 21 and three tripod shaft portions 22. The boss portion 21 has a cylindrical shape, and an inner peripheral spline 21a is formed on the inner peripheral side. The inner peripheral spline 21a is fitted and connected to the outer peripheral spline at the end of the intermediate shaft (not shown). Moreover, the outer peripheral surface of the boss | hub part 21 is formed in the substantially spherical convex shape.

  Here, in the case of a reference posture having a joint angle of 0 deg, the boss portion 21 set to have a spherical convex shape is separated from an intermediate member 40 described later. That is, it is set so that none of the boss portions 21 contacts the intermediate member 40 in the reference posture.

  Each tripod shaft portion 22 is erected so as to extend from the outer peripheral surface of the boss portion 21 outward in the radial direction of the boss portion 21. These tripod shaft portions 22 are formed at equal intervals (120 deg intervals) in the circumferential direction of the boss portion 21. At least the tip of each tripod shaft portion 22 is inserted into each raceway groove 11 of the outer ring 10. These tripod shaft portions 22 include a columnar root portion 22a that is a portion coupled to the boss portion 21, a tip portion 22b whose outer peripheral surface is formed in a spherical convex shape, a root portion 22a, and a tip portion 22b. Are provided with a base portion 22a and a constricted portion 22c having an outer diameter smaller than the outer diameter of the tip portion 22b. Here, a straight line passing through the spherical convex center of curvature of the tip 22b and orthogonal to the rotation axis of the tripod 20 (rotation axis of the intermediate shaft) is the central axis of the tripod shaft 22 (hereinafter also referred to as “tripod axis”). It is.

  Here, in the case of the reference posture having a joint angle of 0 deg, the root portion 22a of the tripod shaft portion 22 is separated from the intermediate member 40 described later. That is, in the case of the reference posture, the root portion 22a of any tripod shaft portion 22 is set so as not to contact the intermediate member 40.

  As shown in FIGS. 3 and 4, the roller unit 30 has an annular shape as a whole, and is disposed on the outer peripheral side of the tripod shaft portion 22. Further, the roller unit 30 is fitted in the raceway groove 11 so as to be movable in the direction in which the raceway groove 11 extends. The roller unit 30 includes an intermediate member 40, a plurality of rolling elements 50, and a cage 60.

  The outer shape of the intermediate member 40 as a whole is formed in a substantially rectangular shape. Furthermore, when the intermediate member 40 is viewed as a whole, a portion corresponding to a circular hole is formed at the center of the intermediate member 40. The intermediate member 40 includes a pair of members 40a and 40b. The pair of intermediate members 40a and 40b are separately configured so as to have a symmetrical shape with respect to a plane passing through the tripod shaft and the rotation shaft of the intermediate shaft, and are independent of each other. Then, as shown in FIG. 2, the pair of intermediate members 40 a and 40 b are arranged so as to sandwich the tripod shaft portion 22 from both sides of the side surface of the raceway groove 11. That is, both the intermediate members 40a and 40b are arranged so as to sandwich the tripod shaft portion 22 from both sides in the power transmission direction (the direction around the outer ring rotation axis or the intermediate shaft rotation axis). The pair of intermediate members 40 a and 40 b are provided so as to be capable of swinging in the rotational axis direction of the outer ring 10 with respect to the tripod shaft portion 22 and swingable in the circumferential direction of the outer ring 10.

  The detailed shape of each intermediate member 40a, 40b will be described with reference to FIG. 5 and FIGS. 6 (a) to 6 (c). The surface of each intermediate member 40a, 40b has a tripod contact surface 41, a power transmission surface 42, and axial end surfaces 44, 45. Here, when the pair of intermediate members 40a and 40b are viewed as one body, the tripod contact surface 41 forms the inner surface, and the power transmission surface 42 and the axial end surfaces 44 and 45 form the outer surface.

  The tripod contact surface 41 is formed in a partially spherical concave shape so as to oscillately contact with the tripod shaft portion 22 in the axial direction of the outer ring 10 and the circumferential direction of the outer ring 10. The center of the spherical surface of the tripod contact surface 41 is the center of the lateral width (the thickness of the intermediate member 40) in FIG. 6A of the tripod contact surface 41 and the vertical width (intermediate member) of the tripod contact surface 41 in FIG. 40 and the center of the outer ring 10 in the axial direction).

  The power transmission surface 42 is provided on the back side of the tripod contact surface 41, that is, on the right side of FIG. The power transmission surface 42 is formed with a concave groove so as to follow the spherical surface of the rolling element 50. And each intermediate member 40a, 40b is arrange | positioned so that the power transmission surface 42 may oppose the side surface of the track groove 11. FIG.

  The power transmission surface 42 is located at the center of the vertical direction in FIG. 6B, and has a width of about 90% of the vertical width in FIG. 6B. That is, the power transmission surface 42 is located on the back surface side of the deepest portion of the tripod contact surface 41. And the power transmission surface 42 has the range which can contact the multiple (in this embodiment, 5-6 pieces) rolling element 50. FIG.

  The axial end faces 44 and 45 are parts located at both upper and lower ends in FIG. Both axial end surfaces 44 and 45 are flat surfaces orthogonal to the power transmission surface 42. That is, the axial end surfaces 44 and 45 are formed of a plane orthogonal to the side surface of the raceway groove 11.

  As shown in FIGS. 2 and 4, the rolling element 50 is a sphere. And the some rolling element 50 is provided so that it may circulate in the outer periphery at the time of seeing a pair of intermediate member 40a, 40b as integral. A part of the plurality of rolling elements 50 (5 to 6 in the present embodiment) is formed between the side surface of the raceway groove 11 and the power transmission surface 42 of the pair of intermediate members 40a and 40b. Rollers are provided along the side surfaces and the power transmission surface 42. That is, power is transmitted between the power transmission surface 42 and the side surface of the raceway groove 11 via the rolling elements 50.

  As shown in FIGS. 7 and 8A, the cage 60 has an annular shape as a whole. The cage 60 includes a pair of circulation path forming members 61 and 62 that form a circulation path of the rolling element 50, and a pair of connecting portions 63 and 64. The pair of circulation path forming members 61 and 62 are positioned on the periphery of the cage 60 and have a rectangular shape with rounded corners. The pair of circulation path forming members 61 and 62 has a shape surrounding the pair of intermediate members 40a and 40b.

  Specifically, the circulation path forming member 61 connects the opposing straight portions 61a and 61b and the straight portions 61a and 61b, and is curved portions 61c and 61d that are curved in a convex shape outward in the radial direction of the outer ring 10. It consists of. The other circulation path forming member 62 is composed of a straight portion and a curved portion, like the circulation path forming member 61. Further, the pair of circulation path forming members 61 and 62 are arranged so as to oppose each other in the vertical direction of FIG. 2, and an arc concave groove is formed so as to support the spherical rolling element 50.

  Further, the maximum width in the facing direction of the pair of circulation path forming members 61 and 62 is set slightly smaller than the width of the side surface of the raceway groove 11. That is, the cage 60 is configured such that its inclination with respect to the track groove 11 is regulated by the groove bottom surface and the locking projection 12 of the track groove 11 and can be inserted into the track groove 11.

  The pair of connecting portions 63 and 64 connect the central portion in the circumferential direction (upper and lower end portions in FIG. 8A) of the curved portions 61c and 61d of the pair of circulation path forming members 61 and 62, respectively. That is, between the pair of circulation path forming members 61 and 62, as shown in FIG. 8 (c), an opening is formed only by a straight part and a part of a curved part connected thereto.

  The connecting portions 63 and 64 are formed in a U-shape that opens to the outside of the cage 60. The U-shaped bottom opening opposite side of the connecting portions 63 and 64 (inside the retainer 60) is formed in a planar shape. And the U-shaped bottom opening opposite side of a pair of connection parts 63 and 64 is provided so that it may oppose in parallel. Further, the distance between the pair of connecting portions 63 and 64 on the opposite side of the bottom surface of the U-shape is substantially the same as the distance between the axial end surfaces 44 and 45 of the intermediate members 40a and 40b. Further, the U-shaped bottom opening side (outside of the retainer 60) of the connecting portions 63 and 64 is formed in a planar shape parallel to the U-shaped bottom opening opposite side.

  In addition, one of the end portions of the connection portions 63 and 64 on the opening side of the U-shape is connected to the central portion in the circumferential direction of each of the curved portion 61c and the curved portion 61d of the circulation path forming member 61, and the other end portion is connected. The curved portion 62c and the curved portion 62d of the circulation path forming member 62 are connected to the respective circumferential center portions.

  Then, the rolling element 50 is inserted into the circular arc concave grooves of the pair of circulation path forming members 61 and 62. In this way, the rolling element 50 is supported by the pair of circulation path forming members 61 and 62. That is, the pair of circulation path forming members 61 and 62 supports the rolling elements 50 such that the plurality of rolling elements 50 can circulate around the outer circumferences of the pair of intermediate members 40a and 40b. Here, the arc-shaped concave grooves of the pair of circulation path forming members 61 and 62 have a shape having a slight gap with respect to the spherical surface of the rolling element 50. Further, in a state where the rolling element 50 is inserted into the circulation path forming members 61 and 62, the rolling element 50 protrudes inward from the inner peripheral edge of the circulation path forming members 61 and 62, and the circulation path forming members 61 and 62 Projects outward from the outer periphery.

  Here, in a state where the pair of intermediate members 40a and 40b are arranged on the outer peripheral side of the tripod shaft portion 22 and the pair of intermediate members 40a and 40b are arranged inside the cage 60, the respective circulation path forming members 61, The straight portions 61a and 61b of 62 (left and right straight portions in FIG. 8A) are substantially parallel to the power transmission surface 42 of the intermediate members 40a and 40b and the side surface of the raceway groove 11 (following state). ). That is, the circulation path formed by the straight portions 61 a and 61 b is a circulation path when the rolling element 50 moves on the power transmission surface 42. Further, a gap is formed in at least one of the straight portions 61 a and 61 b and the side surfaces of the power transmission surface 42 and the raceway groove 11.

  Furthermore, the curved portions 61c and 62c of the pair of circulation path forming members 61 and 62 and both end portions of the curved portions 61d and 62d follow the introduction surfaces formed at both ends of the power transmission surface 42 of the intermediate members 40a and 40b. Placed in. That is, the circulation path formed by the curved portions 61c and 62c and both end portions of the curvature portions 61d and 62d is a circulation path when the rolling element 50 moves on the introduction surface. The circulation path is connected so as to be smoothly continuous with the circulation path formed by the straight portions 61a and 62a and the straight portions 61b and 62d. Further, gaps are formed between the curved portions 61c and 62c and the both ends of the curved portions 61d and 62d forming the circulation path and the introduction surface. In addition, naturally the clearance gap is formed between the both ends of the curved parts 61c and 62c and the curved parts 61d and 62d which form the said circulation path, and the side surface of the track groove 11. FIG.

  Then, depending on the relationship between the shape and the separation distance of the axial end surfaces 44 and 45 of each intermediate member 40a and 40b and the shape and the separation distance of the U-shaped bottom surface of the connection portions 63 and 64 and the separation distance, The intermediate members 40a and 40b are provided between the connecting portions 63 and 64 so that 64 restricts the relative movement of the intermediate members 40a and 40b in the axial direction of the outer ring 10 (vertical direction in FIG. 8A). However, since the intermediate members 40 a and 40 b are not restricted in the radial direction of the outer ring 10 (the vertical direction in FIG. 8B) with respect to the cage 60, the intermediate members 40 a and 40 b are separated from the cage 60. Can be moved in the radial direction (vertical direction in FIG. 8B). That is, the cage 60 does not contact the side surfaces of the pair of intermediate members 40 and the raceway grooves 11 in the power transmission direction.

  The operation of the constant velocity joint 1 described above will be described with reference to FIGS. FIG. 9 is a view seen from the opening side of the outer ring 10 in a state where a joint angle is added to the constant velocity joint 1. 10 is a cross-sectional view taken along the line GG in FIG.

  When the outer ring 10 whose one end is connected to the differential gear receives power and rotates, each tripod shaft portion 22 transmits power through each roller unit 30 fitted in the raceway groove 11, and the tripod 20. The intermediate shaft connecting the two parts rotates at a constant speed. At this time, if the joint angle is not 0 deg, the tripod 20 rotates around the intermediate shaft while being inclined by the joint angle with respect to the rotation axis orthogonal cross section of the outer ring 10. Therefore, when viewed from the side surface of the raceway groove 11, the tripod shaft portion 22 reciprocates in the extending direction of the raceway groove 11 and swings with respect to the raceway groove 11 as the outer ring 10 and the tripod 20 rotate. To do.

  Further, as described above, the tripod 20 is inclined by the joint angle with respect to the rotation axis orthogonal cross section of the outer ring 10, so the angle formed by the tripod shaft parts 22 when viewed from the rotation axis direction of the outer ring 10 is Varies depending on the phase of the intermediate shaft. Therefore, since the three tripod shaft portions 22 are respectively accommodated in the raceway grooves 11, the rotation shaft of the shaft connecting the tripod 20 rotates eccentrically relative to the rotation shaft of the outer ring 10. Therefore, the end of the tripod shaft 22 reciprocates in the radial direction of the outer ring 10 as the outer ring 10 and the tripod 20 rotate.

  Here, the tripod contact surfaces 41 of the pair of intermediate members 40 a and 40 b constituting the roller unit 30 are fitted to the tripod shaft portion 22 so as to be swingable. Further, the pair of intermediate members 40 a and 40 b are regulated in the axial direction of the outer ring 10 by the cage 60 constituting the roller unit 30. Furthermore, the cage 60 is fitted in the raceway groove 11. Therefore, the cage 60 can move in the extending direction of the track groove 11 with respect to the track groove 11, but the inclination with respect to the track groove 11 is substantially constant. And the rolling element 50 has circulated through the outer periphery of a pair of intermediate member 40a, 40b.

  Accordingly, the rolling element 50 has the raceway groove 11 with respect to the raceway groove 11 and the power transmission surface 42 between the power transmission surface 42 of the member on the power transmission side of the intermediate members 40 a and 40 b and the side surface of the raceway groove 11. Rolls without sliding in the stretching direction.

  By the way, the outer ring 10 or the intermediate shaft is not connected to the vehicle when transporting the sliding tripod type constant velocity joint for mounting on the vehicle. Due to these, external force may be applied so that the joint angle is larger than the joint angle when the vehicle is mounted. For this reason, the roller unit 30 may be damaged due to the contact between the intermediate shaft and the roller unit 30 during transportation or assembly to the vehicle. Therefore, it is necessary to regulate the joint angle so that the intermediate shaft and the roller unit 30 do not come into contact with each other during conveyance of the constant velocity joint.

  Here, the tripod contact surfaces 41 of the pair of members 40a and 40b constituting the intermediate member 40 are formed in a spherical concave shape. On the other hand, the outer peripheral surface of the tip portion 22b of the tripod shaft portion 22 is formed in a spherical convex shape. That is, the tip 22b of the tripod shaft 22 and the intermediate member 40 are spherically fitted.

  Therefore, when the tripod shaft 22 reciprocates in the radial direction of the outer ring 10 with respect to the raceway groove 11, the intermediate member 40 moves with the reciprocation of the tripod shaft 22 with respect to the raceway groove 11. That is, when the tripod shaft portion 22 moves inward in the radial direction of the outer ring 10, the intermediate member 40 also moves inward in the radial direction of the outer ring 10.

  As described above, the base portion 22a of the boss portion 21 and the three tripod shaft portions 22 is set so as not to contact the intermediate member 40 in the reference posture where the joint angle is 0 deg. From this reference posture state, the intermediate shaft is tilted with respect to the rotation axis of the outer ring 10 so as to add a joint angle. Specifically, a joint angle is added by tilting the intermediate shaft with respect to the outer ring 10 toward the phase in the central axis direction of the upper tripod shaft portion 22 in FIG.

  Then, since the intermediate shaft rotates eccentrically with respect to the outer ring 10 as described above, the rotation center of the tripod 20 moves downward in FIG. Further, the tripod shaft portion 22 located in the upper part of FIG. 9 swings around the axis perpendicular to the paper surface of FIG. Therefore, as shown in FIGS. 9 and 10, the tripod shaft portion 22 located in the upper part of the figure moves downward in FIGS. 9 and 10, that is, in a direction away from the groove bottom surface of the raceway groove 11. With the operation of the tripod shaft portion 22, the intermediate member 40 located above in FIGS. 9 and 10 moves downward from FIGS. 9 and 10, that is, away from the groove bottom surface of the raceway groove 11 (the center direction of the outer ring 10). Move to).

  As described above, the intermediate member 40 moves toward the center of the outer ring 10 and tilts the tripod 20 with respect to the outer ring 10, so that the intermediate member 40 has the spherical convex surface of the boss portion 21 of the tripod 20 or the tripod shaft portion 22. It approaches the root portion 22a. Further, when the joint angle is added, the intermediate member 40 contacts the spherical convex surface of the boss portion 21 of the tripod 20 or the root portion 22a of the tripod shaft portion 22. Therefore, the contact between the intermediate member 40 and the boss portion 21 or the root portion 22a of the tripod shaft portion 22 can be regulated so that no further joint angle is added.

  As described above, when the joint angle is added, the intermediate member 40 is set so as to come into contact with the boss portion 21 or the root portion 22a of the tripod shaft portion 22, so that no further joint angle is added. Yes. That is, even if an external force that adds a joint angle to the intermediate shaft is applied from the state in which the intermediate member 40 and the boss portion 21 or the root portion 22a of the tripod shaft portion 22 are in contact, the intermediate shaft does not tilt.

  And in the state in which the joint angle is regulated by the contact between the intermediate member 40 and the base portion 22a of the boss portion 21 or the tripod shaft portion 22, the intermediate shaft is not in contact with the cage 60 as shown in FIG. . Therefore, breakage of the cage 60 due to contact between the intermediate shaft and the cage 60 can be prevented.

  The shape of the intermediate member 40 and the base portion 22a of the boss portion 21 or the tripod shaft portion 22 may be appropriately set so as to be regulated by the joint angle immediately before the intermediate shaft and the cage 60 come into contact with each other. In this way, it is possible to prevent the roller unit 30 from being damaged while securing the joint angle required when the vehicle is mounted.

  Further, since the pair of intermediate members are independent from each other, even if the load position by the tripod shaft portion 22 generated on the power transmission side is changed, the operation of the intermediate member 40a (40b) on the power transmission side The operation of the intermediate member 40b (40a) on the side is not affected. Therefore, since the back side of the roller unit 30 can be prevented from applying a large force to the raceway groove, the generation of the induced thrust force can be greatly reduced.

<Others>
As another aspect, in the present embodiment, the intermediate member 40 is composed of a pair of members, but may be integrally formed. In this case, it is excellent in terms of productivity and ease of assembly. However, when the intermediate member 40 is constituted by a pair of independent members, it contributes to a reduction in generation of induced thrust force.

  The rolling element 50 is a sphere, but may be a needle or a barrel-shaped roller. When the rolling element 50 is a cylindrical needle, the needle unit abuts against the side surface of the raceway groove 11 of the outer ring 10 in the cylindrical axis direction to transmit power, so that the roller unit 30 has a small rotational play as a whole. Stable power transmission is possible.

  However, in the present embodiment, when the rolling element 50 is a sphere or barrel-shaped roller, a configuration that can slide between the intermediate member 140 and the rolling element is not suitable. It is preferable to employ a member. With such a configuration, when the intermediate shaft tilts and the tripod shaft portion 122 moves close to the bottom surface of the raceway groove 11, the pair of intermediate members 140 are separated from each other in conjunction with this. Therefore, the power transmission surface 142 of the intermediate members 140a and 140b presses the rolling element against the concave groove on the side surface of the raceway groove 11, whereby the joint angle can be regulated.

FIG. 3 is a view seen from the opening side of the outer ring 10 in a partly assembled state of the constant velocity joint 1. FIG. 3 is a radial sectional view of a part of the constant velocity joint 1. 3 is a perspective view of a roller unit 30. FIG. (A) It is a top view of roller unit 30, (b) A direction arrow view of roller unit 30, (c) B direction arrow view of roller unit 30 3 is a perspective view of one pair of intermediate members 40. FIG. (A) It is a front view of the intermediate member 40, (b) It is CC sectional drawing (a figure containing the partial cross section by the side of a long diameter) of the intermediate member 40, (c) In the D direction arrow view of the intermediate member 40 is there. 3 is a perspective view of a cage 60. FIG. (A) It is a top view of cage 60, (b) It is an E direction arrow view of cage 60, (c) FF sectional view (Drawing including a partial section by the side of a major axis) of cage 60 is there. It is the figure seen from the opening side of the outer ring | wheel 10 in the state which added the joint angle to the constant velocity joint 1. FIG. It is GG sectional drawing of FIG.

Explanation of symbols

1: constant velocity joint 10: outer ring, 11: raceway groove 20: tripod, 21: boss part, 21a: inner peripheral spline 22: tripod shaft part, 22a: root part, 22b: tip part, 22c: constriction part 30: roller Unit 40: intermediate member, 40a, 40b: each intermediate member 41: tripod contact surface, 42: power transmission surface, 44, 45: axial end surface 50: rolling element 60: retainer 61, 62: circulation path forming member 61a, 61b: straight portion, 61c, 61d: curved portion, 63, 64: connecting portion

Claims (5)

An outer ring having a cylindrical shape and formed with three raceway grooves extending in the outer ring rotation axis direction on the inner peripheral surface;
A boss portion coupled to the shaft, and three tripod shaft portions that are erected so as to extend radially outward of the boss portion from the outer peripheral surface of the boss portion and are inserted into the raceway grooves, respectively. Tripod,
Side opposite to the axial direction cross-sectional shape of the raceway grooves have a power transmission surface formed of circularly arcuate concave outer surface, arranged from both sides of the track groove so as to sandwich the tripod shaft part, and the tripod shaft A pair of intermediate members provided to be swingable with respect to the portion ;
A plurality of rolling elements which are spherical or barrel-shaped rollers provided so as to be able to roll along the side surface of the raceway groove between the side surface of the raceway groove and the power transmission surface;
A cage that supports the rolling elements such that the rolling elements can circulate around the outer periphery of the pair of intermediate members;
A sliding tripod type constant velocity joint comprising:
The outer peripheral surface of the tripod shaft portion is a spherical convex shape,
The inner surfaces of the pair of intermediate members are spherical concave shapes fitted to the outer peripheral surface of the tripod shaft part,
The pair of intermediate members move with the reciprocating motion of the tripod shaft portion with respect to the raceway groove when the tripod shaft portion reciprocates with respect to the raceway groove in the radial direction of the outer ring,
A posture in which the outer ring rotation axis and the rotation axis of the shaft coincide with each other is defined as a reference posture,
In the reference posture, the pair of intermediate members is set so as not to contact the base portion of the boss portion and the tripod shaft portion,
When the shaft is tilted with respect to the outer ring rotation shaft so as to add a joint angle from the state of the reference posture, at least one of the intermediate members is located at the root portion of the boss portion or the tripod shaft portion. A sliding tripod constant velocity joint characterized in that the joint angle is regulated by contact.   When the shaft is tilted, the shaft and all the cages are not in contact with at least one of the intermediate members in contact with the boss portion or the base portion of the tripod shaft portion. The sliding tripod type constant velocity joint according to claim 1. When the shaft is tilted to the phase in the central axis direction of any of the tripod shafts in the state of the reference posture, at least one of the intermediate members is the root of the boss part or the tripod shaft part Touch the part,
3. The sliding type according to claim 2, wherein the shaft and all the cages are not in contact with each other in a state where the intermediate member and the base portion of the boss portion or the tripod shaft portion are in contact with each other. Tripod type constant velocity joint. The sliding tripod type constant velocity joint according to any one of claims 1 to 3, wherein a side surface of the raceway groove has a concave groove that follows the spherical convex outer peripheral surface of the rolling element. The joint angle is restricted is in any one of claims 1 to 4, characterized in that than the joint angle when mounting the sliding tripod type constant velocity joint to the vehicle is set to a large angle The sliding tripod type constant velocity joint as described.

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