JP2014031821A - Double offset type constant velocity joint - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid an increase in edge stress of an inner ring ball groove and to avoid reduction in life of a constant velocity joint by preventing a contact ellipse of a ball rolled near to an end part of the shallow side of the inner ring ball groove from being protruded when taking a large joint operation angle.SOLUTION: A double offset type constant velocity joint 10 includes an outer ring 20, an inner ring 30, a ball 40, and a holder 50. A convex spherical surface-like outer peripheral surface 31 of the inner ring 30 includes a first outer spherical surface 31a and a second outer spherical surface 31b having the same spherical surface center (point P1) and respectively different radii. The first outer spherical surface 31a is arranged on the outer ring aperture side of the inner ring 30 and the second outer spherical surface 31b has a radius R2 larger than a radius R1 of the first outer spherical surface 31a and is arranged on the outer ring depth side of the inner ring 30. A recess 55 is formed on a concave spherical surface-like inner peripheral surface 52 of the holder 50, which is opposed to the second outer spherical surface 31b (outer bulge part 34), so as to avoid interference with the second outer spherical surface 31b.

Description

  The present invention relates to a double offset type constant velocity joint used for a driving force transmission shaft portion such as a propeller shaft of a vehicle, for example.

  As a conventional double offset type constant velocity joint, for example, one described in Patent Document 1 is known. The double offset type constant velocity joint is formed in a bottomed cylindrical shape having an opening on one end side in the axial direction, and has an outer ring having a plurality of outer ring ball grooves extending in the axial direction on the inner peripheral surface, and is disposed inside the outer ring. An inner ring having a plurality of inner ring ball grooves extending in the axial direction on the outer peripheral surface of the convex spherical surface, and a plurality of balls that roll on the outer ring ball groove and the inner ring ball groove and transmit torque between the outer ring and the inner ring And a cage having a plurality of windows disposed between the outer ring and the inner ring, each of which accommodates the ball, and a spherical center and a concave spherical inner circumference of the convex spherical outer circumferential surface of the cage The spherical centers of the surfaces are offset equidistant from the joint center to opposite sides in the axial direction.

JP 2003-176833 A

  By the way, in the double offset type constant velocity joint described above, the center of the inner ring is offset in the axial direction from the center of the joint. Yes. In addition, when a joint operating angle is given to the outer ring and the inner ring while the vehicle is running, the ball groove depth is further reduced by rolling the ball toward the inner ring end.

  Therefore, when an excessive torque is applied due to a sudden start of the vehicle or the like, the contact ellipse between the ball and the ball groove protrudes to increase the edge stress of the inner ring ball groove. This will reduce the life of the joint. For this reason, by increasing the size of the constant velocity joint, the stress on the edge of the inner ring ball groove has to be suppressed, causing an increase in the joint weight.

  The present invention has been made in view of the above circumstances, and when the outer ring and the inner ring take a joint operating angle, the contact ellipse of the ball that rolls near the end of the inner ring ball groove on the shallow side (outer ring rear side). Providing a double offset constant velocity joint that prevents the protrusion of the inner ring and avoids an increase in the edge stress of the inner ring ball groove and prevents the joint life from decreasing without increasing the size of the joint This is a problem to be solved.

  (Claim 1) A double offset constant velocity joint according to the present invention includes an outer ring having a plurality of outer ring ball grooves formed in a bottomed cylindrical shape having an opening on one end side in the axial direction and extending in the axial direction on an inner peripheral surface. An inner ring having a plurality of inner ring ball grooves disposed axially on a convex spherical outer peripheral surface disposed inside the outer ring, rolling between the outer ring ball groove and the inner ring ball groove, and between the outer ring and the inner ring A plurality of balls that transmit torque and a cage that is disposed between the outer ring and the inner ring and that has a plurality of windows that respectively accommodate the balls, and the convex spherical outer circumferential surface of the cage In the double offset constant velocity joint in which the spherical center of the spherical center and the concave spherical inner peripheral surface are offset from each other by an equal distance from the joint center in the axial direction, the convex spherical outer peripheral surface of the inner ring has a spherical center A first outer spherical surface and a second outer spherical surface having different radii, wherein the first outer spherical surface is disposed on the outer ring opening side of the inner ring, and the second outer spherical surface is a radius of the first outer spherical surface. The concave spherical inner peripheral surface of the cage has a first spherical inner surface and a second inner spherical surface having the same spherical center and different radii. The first inner spherical surface is disposed on the outer ring opening side of the cage, and the second inner spherical surface has a radius larger than the radius of the first inner spherical surface, and is located on the outer ring inner side of the cage. Is arranged.

  (Claim 2) The first outer spherical surface may be a maximum outer diameter portion of the inner ring in a direction perpendicular to the inner ring rotation axis.

  (Claim 3) Further, a cylindrical first connection surface for connecting the two outer spherical surfaces may be provided between the first outer spherical surface and the second outer spherical surface.

  (Claim 4) Moreover, you may make it provide the conical 2nd connection surface which connects both these internal spherical surfaces between the said 1st internal spherical surface and the said 2nd internal spherical surface.

  (Claim 5) Further, in the axial cross section of the constant velocity joint, an intersection Ia where the first outer spherical surface and the first connecting surface intersect with each other in a state where no joint operating angle is given to the outer ring and the inner ring. An angle formed by a straight line L3 passing through the spherical center P1 of the first outer spherical surface, an intersection point Ca where the first inner spherical surface and the second connecting surface intersect, and a straight line L4 passing through the spherical center P1 of the first inner spherical surface. Is θ1, and the maximum joint operating angle between the outer ring and the inner ring is θjm, the relationship θ1> θjm / 2 may be satisfied.

  (Claim 6) Further, in the axial section of the constant velocity joint, an intersection Ib where the second outer spherical surface and the first connection surface intersect with each other in a state where no joint operating angle is given to the outer ring and the inner ring. An angle formed by a straight line L5 passing through the spherical center P1 of the second outer spherical surface, an intersection Cb where the second inner spherical surface and the second connection surface intersect, and a straight line L6 passing through the spherical center P1 of the second inner spherical surface. Where θ2 is θ2 and the maximum joint operating angle between the outer ring and the inner ring is θjm, the relationship θ2> θjm / 2 may be satisfied.

  (Claim 1) According to the present invention, the convex spherical outer peripheral surface of the inner ring has the first outer spherical surface and the second outer spherical surface having the same spherical center and different radii, respectively. Arranged on the outer ring opening side, the second outer spherical surface has a radius larger than the radius of the first outer spherical surface and is arranged on the outer ring inner side of the inner ring, and the concave spherical inner circumferential surface of the cage has a spherical center at the center. The first inner spherical surface and the second inner spherical surface are the same and have different radii, and the first inner spherical surface is disposed on the outer ring opening side of the cage, and the second inner spherical surface is larger than the radius of the first inner spherical surface. It has a radius and is arranged on the outer ring inner side of the cage. Therefore, when the joint operating angle is given to the outer ring and the inner ring, the contact ellipse of the ball on the inner ring ball groove on the inner ring inner side can be prevented from protruding. As a result, an increase in the edge stress of the inner ring ball groove can be avoided, so that a decrease in the life of the joint can be avoided without increasing the size of the joint.

  (Claim 2) Since the first outer spherical surface is the maximum outer diameter portion of the inner ring in the direction perpendicular to the inner ring rotating shaft, the inner ring can be securely inserted into the cage when the cage and the inner ring are assembled. Can be inserted.

  (Claim 3) In addition, a cylindrical first connection surface for connecting both the outer spherical surfaces is provided between the first outer spherical surface and the second outer spherical surface, so that the joint operating angle is provided between the outer ring and the inner ring. When is provided, the interference between the inner ring and the cage can be more reliably prevented.

  (Claim 4) In addition, a conical second connecting surface for connecting the inner spherical surfaces is provided between the first inner spherical surface and the second inner spherical surface, so that the joint operating angle is provided between the outer ring and the inner ring. When is provided, the interference between the inner ring and the cage can be more reliably prevented.

  (Claim 5) Further, in the axial cross section of the constant velocity joint, the intersection of the first outer spherical surface and the first outer spherical surface intersects with the first outer spherical surface and the first connecting surface in a state where no joint operating angle is given to the outer ring and the inner ring. An angle formed by a straight line L3 passing through the spherical center P1, an intersection Ca where the first inner spherical surface and the second connecting surface intersect, and a straight line L4 passing through the spherical center P1 of the first inner spherical surface is θ1, and the maximum of the outer ring and the inner ring is obtained. By satisfying the relationship of θ1> θjm / 2 when the joint operating angle is θjm, when the joint operating angle is given to the outer ring and the inner ring, interference between the inner ring and the cage is more reliably prevented. can do.

  (Claim 6) Further, in the axial cross section of the constant velocity joint, the intersection point Ib where the second outer spherical surface and the first connection surface intersect with the second outer spherical surface when the joint operating angle is not given to the outer ring and the inner ring. An angle formed by a straight line L5 passing through the spherical center P1, an intersection Cb where the second inner spherical surface and the second connecting surface intersect, and a straight line L6 passing through the spherical center P1 of the second inner spherical surface is θ2, and the maximum of the outer ring and the inner ring is obtained. By satisfying the relationship of θ2> θjm / 2 when the joint operating angle is θjm, when the joint operating angle is given to the outer ring and the inner ring, the interference between the inner ring and the cage is more reliably prevented. can do.

It is sectional drawing which follows the axial direction of the double offset type constant velocity joint which concerns on embodiment. It is a fragmentary sectional view showing composition of an inner ring and a cage of a double offset type constant velocity joint concerning an embodiment. It is a fragmentary sectional view showing composition of an inner ring and a cage in the state where a double offset type constant velocity joint concerning an embodiment took joint operating angle thetaj. It is an enlarged view which expands and shows the A section of FIG. FIG. 4 is a cross-sectional view taken along line B-B in FIG. 3.

  Hereinafter, an embodiment in which a double offset constant velocity joint of the present invention is embodied will be described with reference to the drawings.

  A double offset constant velocity joint 10 (hereinafter, simply referred to as “constant velocity joint”) of the present embodiment will be described with reference to FIGS. In the following description, the opening side of the outer ring 20 (outer ring opening side) means the right side of FIG. 1, and the inner side of the outer ring 20 (outer ring inner side or opposite opening side) is the left side of FIG. means.

  As shown in FIG. 1, the constant velocity joint 10 of the present embodiment is a joint center moving ball type constant velocity joint used for a propeller shaft for transmitting power from an engine to a differential device in a vehicle. For this reason, the maximum joint operating angle θjm of the constant velocity joint 10 is about 5 ° when the vehicle is traveling, which is far more than that of a joint center fixed ball type constant velocity joint used for a drive shaft or the like of 40 ° or more. Small. The constant velocity joint 10 includes an outer ring 20 having a plurality of outer ring ball grooves 23, an inner ring 30 having a plurality of inner ring ball grooves 32, a plurality of balls 40, and a cage 50. Hereinafter, each component will be described in detail.

  The outer ring 20 is formed in a bottomed cylindrical shape having an opening on the right side of FIG. A connecting shaft 21 is integrally formed on the outer side of the outer ring 20 (on the left side in FIG. 1) so as to extend in the direction of the outer ring axis. The connecting shaft 21 is connected to another power transmission shaft. The inner peripheral surface 22 of the outer ring 20 is formed in a straight shape in the axial direction. On the inner peripheral surface 22 of the outer ring 20, a plurality of outer ring ball grooves 23 whose outer ring axis orthogonal cross section is substantially arc-shaped are formed in a straight shape so as to extend substantially parallel to the outer ring axis L1. These outer ring ball grooves 23 (six in this embodiment) are formed at equal intervals in the circumferential direction (60 ° intervals in this embodiment) when viewed in a cross section cut in the radial direction.

  The inner ring 30 is formed in an annular shape and is disposed inside the outer ring 20. The outer peripheral surface 31 of the inner ring 30 is formed in a convex spherical shape. Specifically, the outer peripheral surface 31 of the inner ring 30 has a first outer spherical surface 31a and a second outer spherical surface 31b having the same spherical center and different radii. That is, the first outer spherical surface 31a and the second outer spherical surface 31b have a curvature center at a point P1 offset by a predetermined distance from the intersection (joint center) O between the outer ring axis L1 and the inner ring axis L2 to one side in the axial direction (outer ring opening side). Is formed by a part of a spherical surface drawn as, and is formed in a convex partial spherical shape when viewed in a section cut in the inner ring axial direction. Note that FIG. 1 shows a state where the joint operating angle θj is not applied to the outer ring 20 and the inner ring 30 (a state where θj = 0 °), and therefore the outer ring axis L1 and the inner ring axis L2 are the same.

  In this case, as shown in FIGS. 1 and 2, the first outer spherical surface 31a is formed by a spherical surface having a radius R1 with the point P1 as the center, and the outer ring opening side of the inner ring 30 (point P1 side with respect to the joint center O as a reference). Or on the side from which the power transmission shaft 36 protrudes. On the other hand, the second outer spherical surface 31b is formed by a spherical surface having a radius R2 larger than the radius R1 of the first outer spherical surface 31a, and is located on the outer ring inner side of the inner ring 30 (point P2 side with respect to the joint center O or the power transmission shaft 36). Is located on the non-protruding side). Thus, an outer raised portion 34 that is raised radially outward from the first outer spherical surface 31a with respect to the point P1 is provided at a portion where the second outer spherical surface 31b is provided.

  By providing the second outer spherical surface 31b (outer raised portion 34) in this way, the groove depth on the side where the inner ring ball groove 32 is shallower (outer ring rear side) is smaller than that of the outer raised portion 34. It is deepened by the thickness. As a result, the elliptical contact surface (contact ellipse M1) between the ball 40 and the inner ring ball groove 32 that rolls near the end of the inner ring ball groove 32 on the back side of the outer ring is prevented from protruding from the inner ring ball groove 32. (See FIG. 3). The contact ellipse M1 moves on the inner ring ball groove 32 in a direction parallel to the inner ring axis L2.

  A cylindrical first connection surface 31c that connects the first outer spherical surface 31a and the second outer spherical surface 31b is provided between the first outer spherical surface 31a and the second outer spherical surface 31b. Since the contact ellipse M1 moves in a direction parallel to the inner ring axis L2, the first connecting surface 31c has substantially the same diameter at both axial ends. The first outer spherical surface 31a and the second outer spherical surface 31b are slidably contacted with the inner peripheral surface of the cage 50, and are therefore usually subjected to a polishing process, but the first connection surface 31c is the inner circumferential surface of the cage 50. Therefore, the polishing process can be omitted.

  A plurality of inner ring ball grooves 32 extending in the direction of the inner ring axis L2 are formed on the outer peripheral surface 31 of the inner ring 30. The plurality of (six in this embodiment) inner ring ball grooves 32 are equally spaced in the circumferential direction (60 degree intervals in the present embodiment) and viewed from the outer ring 20 when viewed in a cross section cut in the radial direction. The same number of outer ring ball grooves 23 are formed. That is, each inner ring ball groove 32 is positioned so as to face each outer ring ball groove 23 of the outer ring 20.

  The groove bottom 32a of the inner ring ball groove 32 is formed in a state substantially parallel to the inner ring axis L2. Further, between the two inner ring ball grooves 32, 32 adjacent to each other in the circumferential direction, the radially outer side is equivalent to the depth of the inner ring ball groove 32 from the groove bottom 32 a of the inner ring ball groove 32 to the outer peripheral surface 31. Projections 33 projecting from each other are formed.

  An inner peripheral spline 35 extending in the inner ring axial direction is formed on the inner peripheral surface of the inner ring 30. The inner peripheral spline 35 is fitted (engaged) with an outer peripheral spline formed on the outer periphery of the distal end portion of the power transmission shaft 36 (see FIG. 1). Here, the inner ring axial direction means a direction passing through the central axis of the inner ring 30, that is, a rotation axis direction of the inner ring 30.

  Each of the plurality of balls 40 is disposed so as to be sandwiched between the outer ring ball groove 23 of the outer ring 20 and the inner ring ball groove 32 of the inner ring 30 facing the outer ring ball groove 23. Each ball 40 is rotatable with respect to each outer ring ball groove 23 and each inner ring ball groove 32 and is engaged in a circumferential direction (around the outer ring axis or around the inner ring axis). Therefore, the ball 40 transmits torque between the outer ring 20 and the inner ring 30.

  The cage 50 is formed in an annular shape and is disposed between the inner peripheral surface 22 of the outer ring 20 and the outer peripheral surface 31 of the inner ring 30. The cage 50 has a convex spherical outer peripheral surface 51 that is in sliding contact with the inner peripheral surface 22 of the outer ring 20. The outer peripheral surface 51 is formed by a part of a spherical surface drawn with a point P2 offset by a predetermined distance from the joint center O to the other side in the axial direction (back side of the outer ring) as the center of curvature. On the other hand, the inner peripheral surface 52 of the cage 50 is formed by a part of a spherical surface drawn with the point P1 offset by a predetermined distance from the joint center O to one side in the axial direction (outer ring opening side) as the center of curvature. The inner peripheral surface 52 is formed in a partial spherical shape substantially corresponding to the convex spherical outer peripheral surface 31 of the inner ring 30, that is, a concave spherical shape.

  The offset distance from the joint center O of the point P1 is the same as the offset distance from the joint center O of the point P2. That is, the spherical center (point P2) of the convex spherical outer peripheral surface 51 and the spherical center (point P1) of the concave spherical inner peripheral surface 52 are offset from the joint center O by the same distance on the opposite side in the axial direction. .

  The inner peripheral surface 52 of the cage 50 has a first inner spherical surface 52a and a second inner spherical surface 52b having the same spherical center (point P1) and different radii. That is, the first inner spherical surface 52a and the second inner spherical surface 52b are formed by a part of the spherical surface drawn with the point P1 offset by a predetermined distance from the joint center O to one side in the axial direction (outer ring opening side) as the center of curvature. When viewed in a cross section cut in the inner ring axial direction, it is formed in a concave partial spherical shape.

  In this case, the first inner spherical surface 52a is formed by a spherical surface having a radius R1 with the point P1 as the center, and is disposed on the outer ring opening side of the cage 50. On the other hand, the second inner spherical surface 52b is formed by a spherical surface having a radius R2 larger than the radius R1 of the first inner spherical surface 52a, and is disposed on the inner side of the outer ring of the cage 50. Thereby, a concave portion 55 that is recessed radially outward from the first inner spherical surface 52a with respect to the point P1 is provided at a portion where the second inner spherical surface 52b is provided. The recess 55 is provided so as to avoid interference with the outer raised portion 34 including the second outer spherical surface 31 b provided on the outer peripheral surface 31 of the inner ring 30.

  A conical second connection surface 52c that connects the first inner spherical surface 52a and the second inner spherical surface 52b is provided between the first inner spherical surface 52a and the second inner spherical surface 52b. The second connection surface 52c is formed of a tapered surface having a diameter on the second inner spherical surface 52b side larger than a diameter on the first inner spherical surface 52a side. A predetermined space is formed between the second connection surface 52c and the first connection surface 31c and the first outer spherical surface 31a facing each other.

  The cage 50 has a plurality of window portions 53 arranged at equal intervals in the circumferential direction. The window portions 53 are substantially rectangular through holes penetrating in the thickness direction of the cage 50, and are formed in the same number as the balls 40 (six in this embodiment). Each of the window portions 53 accommodates one ball 40 disposed in each of the outer ring ball groove 23 and the inner ring ball groove 32. Arc concave portions R are provided at the four corners of each window portion 53. Thereby, the strength improvement of each pillar part 54 located between the adjacent window parts 53 is achieved. In this cage 50, the vicinity of the base of the pillar portion 54 on the outer ring opening side is the weakest portion due to stress concentration.

  The cage 50 and the inner ring 30 formed as described above have the following relationship. That is, as shown in FIG. 2, in the axial section of the constant velocity joint 10, the intersection point between the first outer spherical surface 31 a and the first connection surface 31 c in a state where no joint operating angle is given to the outer ring 20 and the inner ring 30. A straight line L3 passing through Ia and the spherical center (point P1) of the first outer spherical surface 31a, an intersection point Ca where the first inner spherical surface 52a and the second connection surface 52c intersect, and a spherical center (point P1) of the first inner spherical surface 52a. When the angle formed by the straight line L4 passing through is θ1 and the maximum joint operating angle of the constant velocity joint 10 is θjm, the relationship θ1> θjm / 2 is satisfied. Specifically, in the present embodiment, since the maximum joint operating angle θjm is about 15 °, the angle θ1 is set to a value larger than 7.5 °.

  Further, as shown in FIG. 2, the spherical center of the intersection point Ib and the second outer spherical surface 31b where the second outer spherical surface 31b and the first connection surface 31c intersect in a state where no joint operating angle is given to the outer ring 20 and the inner ring 30. An angle formed by a straight line L5 passing through (point P1), an intersection Cb where the second inner spherical surface 52b and the second connection surface 52c intersect, and a straight line L6 passing through the spherical center (point P1) of the second inner spherical surface 52b is θ2. When the maximum joint operating angle of the constant velocity joint 10 is θjm, the relationship θ2> θjm / 2 is satisfied. Specifically, since the maximum joint operating angle θjm is 15 °, the angle θ2 is set to a value larger than 7.5 °.

  By satisfying the above two relations, even when the constant velocity joint 10 takes the maximum joint operating angle θjm, the Ia and Ib portions of the inner ring 30 and the Ca and Cb portions of the cage 50 interfere with each other. Not to be.

  Next, the operation of the constant velocity joint 10 of this embodiment will be described with reference to FIGS. FIG. 3 is a partial cross-sectional view showing the configuration of the inner ring and the cage in a state where the constant velocity joint has a joint operating angle θj. FIG. 4 is an enlarged view showing a portion A of FIG. 5 is a cross-sectional view taken along line BB in FIG. In FIG. 3, L7 is the axis of the cage 50.

  In the constant velocity joint 10 of the present embodiment, when a joint operating angle θj is given to the outer ring 20 and the inner ring 30, the balls 40 disposed in the outer ring ball grooves 23 and the inner ring ball grooves 32 pass through the ball grooves 23 and 32. Roll. As shown in FIGS. 3 to 5, when the ball 40 rolls to the side where the inner ring ball groove 32 has a shallow groove depth (outer ring back side), the second outer spherical surface is formed on the outer circumferential surface 31 of the inner ring 30. Since the groove depth of the inner ring ball groove 32 is increased by the provision of 31b and the outer raised portion 34, the protrusion of the contact ellipse M1 of the ball 40 from the inner ring ball groove 32 is reliably prevented. As a result, an increase in the edge stress of the inner ring ball groove 32 is avoided, so that it is possible to avoid a decrease in the life of the constant velocity joint 10 without increasing the size of the joint.

  As described above, according to the constant velocity joint 10 of the present embodiment, the outer peripheral surface 31 of the inner ring 30 has the first outer spherical surface 31a and the second outer spherical surface 31b having the same spherical center (point P1) and different radii. The first outer spherical surface 31a is disposed on the outer ring opening side of the inner ring 30, and the second outer spherical surface 31b has a radius R2 larger than the radius R1 of the first outer spherical surface 31a and The concave spherical inner peripheral surface 52 of the cage 50 has a first inner spherical surface 52a and a second inner spherical surface 52b having the same spherical center (point P1) and different radii, and the first inner spherical surface 52a. Is arranged on the outer ring opening side of the cage 50, and the second inner spherical surface 52b has a radius larger than the radius of the first inner spherical surface 52a and is arranged on the inner side of the outer ring of the cage 50. Therefore, even when the joint operating angle θj is given to the outer ring 20 and the inner ring 30, the contact ellipse M1 of the ball 50 on the inner ring ball groove 32 on the back side of the outer ring can be prevented. As a result, an increase in edge stress of the inner ring ball groove 32 can be avoided, so that a decrease in the life of the constant velocity joint 10 can be avoided without increasing the size of the joint.

  In the present embodiment, a cylindrical first connection surface 31c that connects both the outer spherical surfaces 31a and 31b is provided between the first outer spherical surface 31a and the second outer spherical surface 31b. Therefore, when the joint operating angle θj is given to the outer ring 20 and the inner ring 30, the interference between the inner ring 30 and the cage 50 can be prevented more reliably. In addition, a cylindrical second connection surface 52c is provided between the first inner spherical surface 52a and the second inner spherical surface 52b so as to connect both the inner spherical surfaces 52a and 52b. The interference of the device 50 can be prevented more reliably.

  Furthermore, since the first connection surface 31c of the present embodiment is formed by a tapered surface having a diameter on the first outer spherical surface 31a side larger than a diameter on the second outer spherical surface 31b side, the inner ring ball of the contact ellipse M1 The protrusion from the groove 32 can be prevented more reliably.

  Further, in the present embodiment, since the relationship of θ1> θjm / 2 and the relationship of θ2> θjm / 2 are satisfied, even when the maximum joint operation angle θjm is given to the outer ring 20 and the inner ring 30, the inner ring Interference between 302 and the cage 50 can be prevented more reliably.

  In the present embodiment, the first outer spherical surface 31a is the maximum outer diameter portion of the inner ring 30 in the direction perpendicular to the inner ring rotation axis. Therefore, when the cage 50 and the inner ring 30 are assembled, The inner ring 30 can be reliably inserted.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the outer ring 20 of the above embodiment is formed in a bottomed cylindrical shape having an opening at one end in the axial direction, whereas the outer ring 20 is formed in a cylindrical shape having openings at both axial ends. Also, a bottomed cylindrical outer ring according to the present invention includes a partition member that is a bottom portion such as a plate, which is assembled later in one opening.

    10: Ball type constant velocity joint, 20: Outer ring, 21: Connection shaft, 22: Inner peripheral surface, 23: Outer ring ball groove, 30: Inner ring, 31: Outer peripheral surface, 31a: First outer spherical surface, 31b: Second outer Spherical surface, 31c: first connecting surface, 32: inner ring ball groove, 34: outer raised portion, 40: ball, 50: cage, 51: outer peripheral surface, 52: inner peripheral surface, 52a: first inner spherical surface, 52b : Second inner spherical surface, 52c: second connecting surface, 53: window portion, 54: column portion, 55: recessed portion, L1: outer ring axis, L2: inner ring axis, L3 to L6: straight line, L7: cage axis, O : Joint center, P1: spherical center of concave spherical inner peripheral surface of cage, P2: spherical center of convex spherical outer circumferential surface of cage, θ1: angle formed by straight line L3 and straight line L4, θ2: straight line L5 Angle formed by the straight line L6, θjm: maximum Yointo operating angle.

Claims (6)

An outer ring having a plurality of outer ring ball grooves formed in a bottomed cylindrical shape having an opening on one end side in the axial direction and extending in the axial direction on the inner peripheral surface;
An inner ring disposed inside the outer ring and having a plurality of inner ring ball grooves extending axially on a convex spherical outer peripheral surface;
A plurality of balls that roll on the outer ring ball groove and the inner ring ball groove and transmit torque between the outer ring and the inner ring;
A cage having a plurality of windows disposed between the outer ring and the inner ring and respectively accommodating the balls;
In the double offset type constant velocity joint in which the spherical center of the convex spherical outer peripheral surface of the cage and the spherical center of the concave spherical inner peripheral surface are offset equidistant from each other in the axial direction from the joint center,
The convex spherical outer peripheral surface of the inner ring has a first outer spherical surface and a second outer spherical surface having the same spherical center and different radii,
The first outer spherical surface is disposed on the outer ring opening side of the inner ring,
The second outer spherical surface has a radius larger than the radius of the first outer spherical surface and is disposed on the outer ring inner side of the inner ring,
The concave spherical inner peripheral surface of the cage has a first inner spherical surface and a second inner spherical surface having the same spherical center and different radii,
The first inner spherical surface is disposed on the outer ring opening side of the cage,
The double offset constant velocity joint, wherein the second inner spherical surface has a radius larger than the radius of the first inner spherical surface and is disposed on the outer ring inner side of the cage.   2. The double offset constant velocity joint according to claim 1, wherein the first outer spherical surface is a maximum outer diameter portion of the inner ring in a direction perpendicular to the inner ring rotation axis.   The double offset type constant velocity joint according to claim 1 or 2, wherein a cylindrical first connection surface that connects the two outer spherical surfaces is provided between the first outer spherical surface and the second outer spherical surface. .   The double according to any one of claims 1 to 3, wherein a conical second connection surface that connects both the inner spherical surfaces is provided between the first inner spherical surface and the second inner spherical surface. Offset type constant velocity joint.   In a cross section in the axial direction of the constant velocity joint, an intersection point Ia where the first outer spherical surface and the first connection surface intersect with the spherical surface of the first outer spherical surface in a state where no joint operating angle is given to the outer ring and the inner ring. An angle formed by a straight line L3 passing through the center P1, an intersection Ca where the first inner spherical surface and the second connecting surface intersect, and a straight line L4 passing through the spherical center P1 of the first inner spherical surface is θ1, and the outer ring 5. The double offset constant velocity joint according to claim 4, wherein a relation of θ1> θjm / 2 is satisfied when a maximum joint operating angle of the inner ring is θjm.   In a cross section in the axial direction of the constant velocity joint, an intersection Ib where the second outer spherical surface and the first connection surface intersect with the spherical surface of the second outer spherical surface in a state where no joint operating angle is given to the outer ring and the inner ring. An angle formed by a straight line L5 passing through the center P1, an intersection Cb where the second inner spherical surface and the second connecting surface intersect, and a straight line L6 passing through the spherical center P1 of the second inner spherical surface is defined as θ2, and the outer ring 5. The double offset constant velocity joint according to claim 4, wherein a relation of θ2> θjm / 2 is satisfied when a maximum joint operating angle of the inner ring is θjm.

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