JP2004257418A - Tripod uniform velocity universal joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the weight, to make compact/to reduce the cost, maintaining the strength of a neck bottom of a trunnion journal of a tripod uniform velocity universal joint. <P>SOLUTION: In the tripod uniform velocity universal joint of a high durable type in which a clearance between an inside roller 22 and the trunnion journal 16b is held narrowly, a root part of the tripod journal 16b is made a non-circular section in which the diameter of a joint circumferential direction is larger than the the diameter of the joint axial direction. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The tripod-type constant velocity universal joint according to the present invention is incorporated in, for example, a drive system of an automobile, and is used when torque is transmitted at a constant angular velocity between non-linear rotating shafts.
[0002]
[Prior art]
A tripod type constant velocity universal joint is widely used as a kind of constant velocity universal joint incorporated in a drive system of an automobile. For example, Japanese Unexamined Patent Publication No. 62-233522 discloses a tripod type constant velocity universal joint as shown in FIGS. The tripod type constant velocity universal joint 1 includes a hollow cylindrical housing 3 fixed to an end of a first rotary shaft 2 such as a drive shaft, and an end of a second rotary shaft 4 such as a wheel-side rotary shaft. And a tripod 5 fixed to the part.
[0003]
A concave groove 6 extending in the axial direction of the housing 3 is formed on the inner peripheral surface of the housing 3 at a position equally divided in the circumferential direction. On the other hand, the tripod 5 is composed of a boss 7 for fixing to the end of the second rotary shaft 4, and a cylindrical trunnion journal 8 protruding in the radial direction from a position at which the boss 7 is equally divided in the circumferential direction. You. Each trunnion journal 8 supports a roller 9 via a needle roller 10 so as to be rotatable and slightly displaceable in the axial direction. The tripod type constant velocity universal joint 1 is formed by fitting these rollers 9 into the concave grooves 6 of the housing 3. A pair of guide surfaces 6a constituting each groove 6 is an arc-shaped concave surface, and each roller 9 is supported between these pair of guide surfaces 6a so as to roll and swing freely.
[0004]
When the tripod-type constant velocity universal joint 1 configured as described above is used, for example, when the first rotating shaft 2 rotates, the rotational force is transmitted from the housing 3 via the roller 9, the needle roller 10, and the trunnion journal 8. 5 and the second rotating shaft 4 is rotated. Also, as shown in FIG. 18, when the central axis of the first rotary shaft 2 and the central axis of the second rotary shaft 4 do not match, that is, when the tripod type constant velocity universal joint 1 has an operating angle, As shown in FIGS. 17 and 18, each trunnion journal 8 is displaced with respect to the guide surface 6a of the corresponding groove 6 with the rotation of the rotating shafts 2 and 4 in the direction of swinging about the tripod 5, as shown in FIGS. I do. At this time, the rollers 9 supported by the trunnion journals 8 roll on the guide surfaces 6 a of the concave grooves 6 and are displaced in the axial direction of the trunnion journals 8. By these movements, as is well known, constant velocity between the first and second rotating shafts 2 and 4 is ensured.
[0005]
[Patent Document 1]
JP-A-62-233522
(Page 14, lower right column, line 14 to page 2, lower left column, line 17, FIGS. 7 and 8)
[Patent Document 2]
French Patent No. 2,752,890
(Page 3, line 29 to page 6, line 11, FIGS. 2 and 3B)
[0006]
[Problems to be solved by the invention]
In the case of the conventional tripod type constant velocity universal joint 1 described above, when the first and second rotating shafts 2 and 4 are rotated in a state where the operating angle is set, each roller 9 performs a complicated movement. That is, each roller 9 moves while changing its direction in the axial direction of the housing 3 along the guide surface 6a, and is displaced in the axial direction of the trunnion journal 8. When each roller 9 makes such a complicated movement, the relative displacement between the outer peripheral surface of each roller 9 and the guide surface 6a is not always smooth, and relatively large friction is generated between these two surfaces. As a result, in the case of a tripod-type constant velocity universal joint having a structure as shown in FIGS. 17 and 18, a tertiary axial force for one rotation is generated. It is known that vibrations called judder occur in a remarkable case such as when a large torque is transmitted in a state of being installed in an automobile and having a large operating angle.
[0007]
As means for solving the above problems, a structure shown in FIG. 19 is proposed in French Patent No. 2,752,890. The structure shown in FIG. 19 guides the rollers (9a, 9b) in parallel with the groove of the housing, and the centering and swinging are performed between the spherical inner peripheral surface of the inner roller 9a and the spherical outer peripheral surface of the trunnion journal 8. Possible spherical fitting structure. When the radius of curvature rT of the generatrix of the trunnion journal 8 is made smaller than the radius R of the trunnion journal 8 and the rollers (9a, 9b) are inclined in the joint circumferential direction with respect to the trunnion journal 8 as shown in FIG. <ΦB is satisfied, and the flat surface portion 8a is provided to enable spherical fitting.
[0008]
However, in this case, it is necessary to reduce the curvature rT of the trunnion journal 8 with respect to the curvature of the inner spherical surface of the inner rollers 9a which are spherically fitted to each other, and there is a problem that the surface pressure increases. Even if the curvature rT of the trunnion journal 8 is not reduced, it is possible to assemble it by setting the clearance between the spherical surfaces to be large, but in this case, there is a problem that play in the rotational direction of the joint becomes large. In addition, since it is necessary to avoid interference between the root portion of the trunnion journal and the roller in the circumferential direction of the joint receiving the torque load, there is a limit to increasing the diameter of the trunnion journal below the neck. In addition, when a limit design is performed for the purpose of reducing the size and weight, the root portion of the trunnion journal in the circumferential direction of the joint receiving the torque load is likely to be the weakest portion of the trunnion journal, and it is difficult to secure high strength.
[0009]
An object of the present invention is to eliminate the above-mentioned problems. That is, the present invention provides a highly durable tripod type in which the surface pressure is reduced by spherical fitting while reducing the clearance between the inner roller and the trunnion journal fitted with spherical surface and keeping the play in the rotational direction small. It is an object of the speed universal joint to achieve light weight, compactness and low cost while securing the strength under the trunnion journal neck.
[0010]
[Means for Solving the Problems]
The tripod type constant velocity universal joint according to the present invention is characterized in that an end of the first rotary shaft 12 having a concave groove 14a opened at one end in the axial direction and extending in the axial direction at three equally-divided positions on the inner peripheral surface in the circumferential direction. A hollow cylindrical housing 14 fixed to the part,
A boss 16a fixed to an end of the second rotating shaft 13, and a tripod 16 including a trunnion journal 16b whose end protruding in a radial direction from a circumferentially trisected position of the boss 16a,
An inner roller 22 whose inner peripheral surface is swung freely around the spherical outer peripheral surface of the trunnion journal 16b, and an outer roller 26 supported on the outer peripheral surface of the inner roller 22 via a needle roller 24 so as to be rotatable and axially movable. And a roller assembly 20 comprising
The outer roller 26 is accommodated in the concave groove 14a of the housing 14 so as to freely roll in the axial direction of the housing. The concave groove 14a contacts the outer peripheral surface of the outer roller 26 with the guide surface 14b receiving the load and the outer roller 26. It consists of a guide shoulder surface 14c that guides in the direction,
When assembling the roller assembly into the trunnion journal, in the tripod type constant velocity universal joint 11 in which the roller assembly is inclined and assembled in the joint axial direction,
The base of the tripod journal 16b has a non-circular cross section whose diameter in the joint circumferential direction is larger than the diameter in the joint axial direction.
[0011]
An example of the non-circular shape in which the diameter in the joint circumferential direction is larger than the diameter in the joint axial direction includes an elliptical shape whose short axis is directed in the joint axial direction (see FIG. 1B). By assembling the roller assembly with the trunnion journal by tilting it in a plane including the joint axial direction, interference relief for assembling the lower part of the journal neck and the roller only needs to be present on the joint axial direction side of the lower part of the journal neck. In addition, no interference relief for assembly is required on the circumferential side of the joint. In the case of such a specification, there is no interference escape at the position below the neck in the circumferential direction, which is likely to be the maximum stress position when receiving a torque load, so that the strength can be improved and a more compact joint can be obtained.
[0012]
The outer diameter of the boss 16a of the tripod 16 on the end side of the second rotating shaft 13 may be chamfered (16c) so that the roller assembly 20 is inclined when the roller assembly 20 is inclined and assembled to the trunnion journal 16b. Since the assembly 20 can be tilted more largely, and the torque transmission between the tripod 16 and the second rotating shaft 13 at the time of assembly is mostly performed on the boss 16a on the second rotating shaft non-end side, Even if the boss 16a is chamfered largely at the end of the second rotating shaft 13, the strength of the boss does not decrease.
[0013]
A relief 16e (FIGS. 6 and 8) may be provided partially along the forging parting line 16d of the trunnion journal 16b so that the projection height of the parting line is equal to or less than the spherical diameter of the trunnion journal 16b. By providing the relief 16e, the raised portion of the forged parting line 16d retreats inward from the spherical diameter of the trunnion journal 16b, so that the inner roller 22 and the trunnion journal can be removed without removing the raised portion of the forged parting line 16d. 16b can be spherically fitted to a small gap, and the surface pressure is reduced. Therefore, according to the present invention, it is possible to provide a tripod-type constant velocity universal joint that achieves both reduction of judder when assembled to a vehicle, high durability, and low cost.
[0014]
The cross-sectional shape of the trunnion journal 16b in the torque load region may be substantially a two-spherical shape (FIG. 9). In this case, since the parting line position of the trunnion journal 16b is retracted to the smaller diameter side than the inner spherical surface of the inner roller 22, the relief 16e is formed without taking any other means. In the torque load state, the contact portion between the trunnion journal 16b and the inner roller 22 is located at two symmetrical positions with the forged parting line 16d of the trunnion journal 16b interposed therebetween. Don't worry.
[0015]
As a specific mode of the above-described substantially spherical surface shape, assuming that the radius of curvature of the spherical inner peripheral surface of the inner roller 22 is r, the radius R of the spherical surface of the trunnion journal 16b is in the range of r / 2 <R <r. You can list what you have set.
[0016]
Assuming that the angle at which the roller assembly 20 starts to separate from the trunnion journal 16b is θ1, after attaching the rotating shaft (13, 13a) to the tripod kit (16, 20), the roller assembly 20 is moved to the angle θ2 (θ2 <θ1). It can be set so as to interfere with the rotation axis (13, 13a) when tilted (FIG. 12). Here, a unit including the tripod 16 and the roller assembly 20 is referred to as a tripod kit. Further, the rotating shaft includes not only the rotating shaft 13 itself but also another member attached to the rotating shaft 13 such as a retaining ring 13a. By adopting such a configuration, the tripod 16 is assembled to the second rotating shaft 13 in a unit composed of the tripod 16 and the roller assembly 20, that is, a tripod kit, and once the retaining ring 13a is mounted, the retaining ring 13a or The inner roller 22 cannot be tilted to the angle θ1 at which the inner roller 22 separates from the trunnion journal 16b due to interference with the rotating shaft 13, and the tripod kit (16, 20) and the rotating shaft 4 are in a unit handling state, so that handling is very easy. become.
[0017]
A needle retainer (26a or 26b) can be integrally provided on at least one end of the inner peripheral surface of the outer roller 26 (FIG. 13). By forming both the inner needle retainer 26a and the outer needle retainer 26b integrally with the outer roller 26, a roller assembly can be configured with only the three members of the inner roller 22, the needle roller 24, and the outer roller 26, and the number of parts can be reduced. Can be reduced.
[0018]
A needle retainer (22a or 22b) can be integrally provided on at least one end of the outer peripheral surface of the inner roller 22 (FIG. 14). By forming both the inner needle retainer 22a and the outer needle retainer 22b integrally with the inner roller 22, a roller assembly can be configured with only the three members of the inner roller 22, the needle roller 24, and the outer roller 26, and the number of parts can be reduced. Can be reduced.
[0019]
The inner diameter Di of the inner diameter side end of the cylindrical inner peripheral surface of the outer roller 26 can be smaller than the outer diameter do of the inner roller 22 (Di <do) (FIG. 15). By employing such a configuration, the outer roller 26 is less likely to be disassembled from the inner roller 22 in the state of the tripod kit (16, 20), so that handling is facilitated.
[0020]
The outer diameter do of the outer diameter side edge of the cylindrical outer peripheral surface of the inner roller 22 can be made larger than the inner diameter Di of the outer roller 26 (do> Di) (FIG. 16). By employing such a configuration, the outer roller 26 is less likely to be disassembled from the inner roller 22 in the state of the tripod kit (16, 20), so that handling is facilitated.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, the basic configuration will be described with reference to FIGS. 2 and 3. A tripod type constant velocity universal joint 11 includes a hollow cylindrical housing 14 fixed to an end of a first rotary shaft 12 such as a drive shaft, and a wheel. And a tripod 16 fixed to the end of the second rotating shaft 13 such as the rotating shaft on the side.
[0022]
The housing 14 is formed integrally with the first rotating shaft 12 and has a groove 14a extending in the axial direction at a position on the inner peripheral surface that is equally divided in the circumferential direction. Each concave groove 14a is recessed radially outward from the inner peripheral surface of the housing 14, and has a pair of guide surfaces 14b facing in the circumferential direction. And a bottom surface connecting the surfaces 14b. The pair of guide surfaces 14b provide an orbit for guiding and rolling an outer roller 26 described later in the axial direction of the housing, and transmit torque between the outer roller 26 and the outer roller 26. Further, a guide shoulder surface 14c for guiding the rolling of the outer roller 26 is formed on a part of the bottom surface of the concave groove 14a. The guide shoulder surface 14c serves to maintain a posture parallel to the axial direction of the housing and smoothly roll when the outer roller 26 moves in the concave groove 14a.
[0023]
The tripod 16 includes a boss 16a and a trunnion journal 16b. The boss 16a is fixed to an end of the second rotation shaft 13. For example, a spline shaft formed in the second rotating shaft 13 and a spline hole formed in the boss 16a are fitted and positioned by the retaining ring 13a. The trunnion journal 16b protrudes in the radial direction from a circumferentially equal position of the boss 16a. The end of each trunnion journal 16b has a spherical shape.
[0024]
Each trunnion journal 16b supports a roller assembly 20. The roller assembly 20 is of a double roller type including an inner roller 22 and an outer roller 26 which are relatively rotatable via a needle roller 24. The inner peripheral surface of the inner roller 22 has a spherical shape having substantially the same radius of curvature as the spherical outer peripheral surface of the trunnion journal 16b, and the inner roller 22 and the trunnion journal 16b are spherically fitted. Thus, the spherical inner peripheral surface of the inner roller 22 is swingably supported around the spherical outer peripheral surface of the trunnion journal 16b.
[0025]
A needle roller 24 is interposed between the cylindrical outer peripheral surface of the inner roller 22 and the cylindrical inner peripheral surface of the outer roller 26. Therefore, the inner roller 22 and the outer roller 26 can be relatively rotated and axially displaced. In order to prevent the needle roller 24 from coming off, annular needle retainers 25a are arranged at both ends of the needle roller 24, and retaining rings 25b are attached to retaining ring grooves formed on the inner peripheral surfaces of both ends of the outer roller 26, and the needle retainer is mounted. 25a is retained (see FIG. 4).
[0026]
The outer roller 26 is housed in the concave groove 14a of the housing 14. A pair of guide surfaces 14b constituting each concave groove 14a has a substantially arc shape that is substantially the same as the generatrix of the outer peripheral surface of the outer roller 26 in the cross section of the housing 14 (FIG. 2). Therefore, the outer roller 26 is rotatably supported between the pair of guide surfaces 14b.
[0027]
When the tripod type constant velocity universal joint configured as described above is used, for example, when the first rotating shaft 12 rotates, the rotational force is transmitted from the housing 14 via the roller assembly 20 and the trunnion journal 16b to the boss 16a of the tripod 16. And the second rotating shaft 13 is rotated. In addition, as shown in FIG. 3, when the center axis of the first rotating shaft 12 and the center axis of the second rotating shaft 13 do not coincide with each other, in other words, when the operating angle is set, the rotation of both the rotating shafts is caused. Each trunnion journal 16b is displaced in the direction of swinging about the tripod 16 with respect to the corresponding guide surface 14b of the concave groove 14a. At this time, the outer roller 26 supported by the trunnion journal 16b rolls on the guide surface 14b of the groove 14a and is displaced in the axial direction of the trunnion journal 16b. By these movements, as is well known, constant velocity between the first and second rotating shafts 12 and 13 is ensured.
[0028]
As shown in FIG. 1, the root portion of the tripod journal 16b has a non-circular cross section whose diameter in the joint circumferential direction is larger than the diameter in the joint axial direction. FIG. 1B shows an elliptical shape in which the short axis is directed in the joint axis direction as a typical non-circular example in which the diameter in the joint circumferential direction is larger than the diameter in the joint axial direction.
[0029]
FIG. 5 shows a procedure for assembling the roller assembly 20 to the tripod journal 16b. As shown by the reference numeral 16c in the figure, a large chamfer is provided only on the end portion of the boss 16a of the tripod 16 on the end side of the second rotating shaft 13 (the right side in FIG. 3, the left side in FIG. 5). This large chamfer serves as an interference escape between the trunnion journal 16b and the roller assembly 20, and when the roller assembly 20 is assembled to the trunnion journal 16b, the roller assembly 20 can be tilted greatly as shown by the imaginary line in FIG. I do. The roller assembly 20 (the inner roller 22 thereof) and the trunnion journal 16b interfere with each other only at two opposing positions in the direction in which the torque load acts (the direction perpendicular to the plane of FIG. 5). Can be assembled by pushing in while elastically deforming.
[0030]
The interference relief between the trunnion journal 16b and the roller assembly 20 only needs to exist at the lower part of the trunnion journal in the joint axial direction, and is unnecessary at the lower part of the trunnion journal in the joint circumferential direction. In the case of this specification, interference relief at the circumferential position under the neck, which tends to be the maximum stress position when receiving a torque load, is not necessary, so strength can be improved and a more compact tripod type constant velocity universal joint can be made. It becomes. Further, a plane may be provided at two positions (outside the load range) perpendicular to the position where the trunnion journal 16b receives the torque load and may escape.
[0031]
According to the above structure, in the high performance type tripod type constant velocity universal joint, the torque is transmitted between the spherical inner peripheral surface of the inner roller 22 and the spherical trunnion journal 16b, so that the contact surface pressure is suppressed low and the strength is reduced.・ Because it is advantageous for durability and also improves the strength under the neck of the trunnion journal 16b, it is possible to provide a tripod type constant velocity universal joint that satisfies all of high performance, high strength, high durability and compactness. Become.
[0032]
In the embodiment shown in FIG. 6, the outer peripheral surface of the trunnion journal 16b has a spherical shape that is spherically fitted to the spherical inner peripheral surface of the inner roller 22, but the raised portion of the forging parting line 16d is indicated by a broken line in FIG. A relief 16e is provided partially along the forging parting line 16d so as not to recede inward from the spherical surface diameter indicated by and to protrude therefrom. For this reason, it is possible to omit the step of removing the protruding portion of the forging parting line 16d, and it is possible to use the cold-formed surface as it is, thereby achieving cost reduction. In this case, the load area is small because the relief 16e cannot receive the load, but the load area is small because the trunnion journal 16b and the inner roller 22 are loaded in a wide range by spherical fitting. Even in this case, a sufficient load point can be maintained. Further, when the relief 16e is provided, an effect of reducing interference when the inner roller 22 is assembled to the trunnion journal 16b is obtained as compared with the case without the relief 16e, and the elastic deformation amount of the inner roller 22 is reduced, or Can be eliminated.
[0033]
Various embodiments of the escape 16e are conceivable. The simplest example is to cut out a part of the spherical surface to form a flat surface as shown in FIG. However, when the relief portion is provided by simply removing a part of the spherical surface, the width dimension A of the relief portion increases, and the load receiving area decreases. Therefore, for example, as shown in FIGS. 8A to 8C, a relief 16e having an arc shape in the longitudinal section of the trunnion journal 16b may be used. In the case of this embodiment, there is an advantage that the relief width B is small and the area receiving the load is large. However, in both embodiments, the contact state is as shown in FIG. 7B, and stress concentration occurs at the edge portion, causing early peeling. Even if the corner R is set at the edge, a sufficient effect may not be obtained.
[0034]
In the embodiment shown in FIG. 9, the outer shape of the torque load region of the trunnion journal 16b is substantially a two-spherical shape. Specifically, assuming that the radius of curvature of the spherical inner peripheral surface of the inner roller 22 is r, the radius R of the two spherical surfaces of the trunnion journal 16b is set in the range of r / 2 <R <r. In this case, since the parting line position is retracted to the smaller diameter side than the inner spherical surface of the inner roller, the relief 16e is formed without taking any other means. In the torque load state, the contact portions between the trunnion journal 16b and the inner rollers 22 are located at two symmetrical positions with respect to the forging parting line 16d of the trunnion journal 16b.
[0035]
The embodiment shown in FIG. 10 shows a trunnion journal including the outermost portion of the forging parting line 16d when the angle of inclination when assembling the roller assembly 20 (the inner roller 22 thereof) to the trunnion journal 16b is θ. The projection maximum diameter φD from the angle θ direction of 16 b is set smaller than the inner diameter φd of the inner roller 22 on the fitting / insertion side.
[0036]
In the embodiment shown in FIG. 11, a notch is partially provided in the inner diameter of the inner roller 22 on the insertion side, the inner diameter of the notch is φd2, and the angle θ direction of the trunnion journal 16b (including the forged parting line 16d). Is set such that φD2 <φd2, where φD2 is the maximum projected diameter of φD2. This makes it possible to assemble the roller assembly 20 without elastically deforming the inner roller 22 when assembling the roller assembly 20 to the trunnion journal 16b. Therefore, according to this embodiment, the forging parting line removing step and the press-fitting step when assembling the roller assembly 20 to the trunnion journal 16b can be omitted.
[0037]
In the embodiment shown in FIG. 12, when the roller assembly 20 is inclined with respect to the trunnion journal 16b and the angle at which the inner roller 22 comes off the trunnion journal 16b is θ1, the angle of the inner roller 22 is slightly smaller than θ1. Are set such that the outer roller 26 interferes with the second rotating shaft 13 or the retaining ring 13a when the angle θ2 becomes smaller. By adopting such a configuration, the tripod 16 is assembled to the second rotating shaft 13 in a unit composed of the tripod 16 and the roller assembly 20, that is, a tripod kit, and once the retaining ring 13a is mounted, the retaining ring 13a or A unit in which the inner roller 22 cannot be inclined to the angle θ1 at which the inner roller 22 is separated from the trunnion journal 16b due to interference with the second rotating shaft 13, and the tripod kit (16, 20) and the rotating shaft 13 are not disassembled. It becomes a handling state, and handling becomes easy.
[0038]
In the embodiment shown in FIG. 13, protrusions are provided circumferentially at both ends of the cylindrical inner peripheral surface of the outer roller 26 to integrally form the needle retainers 26a and 26b. As shown, both the needle retainers 26a and 26b may be integrated with the outer roller 26, or only one of the inner and outer rollers may be integrated with the outer roller 26, and the other may be separate.
[0039]
In the embodiment shown in FIG. 14, protrusions are provided on both ends of the cylindrical outer peripheral surface of the inner roller 22 over the entire circumference to integrally form the needle retainers 22a and 22b. As shown, both the needle retainers 22a and 22b may be integrated with the inner roller 22, or only one of the inner and outer rollers may be integrated with the outer roller 22, and the other may be separate.
[0040]
In the embodiment shown in FIG. 15, when the inner diameter of the inner needle retainer 26a of the outer roller 26 is φDi and the outer diameter of the inner roller 22 is φdo, the relationship φDi <φdo is set. In this embodiment, since the relationship φDi <φdo is set, the outer roller 26 is less likely to be disassembled from the inner roller 22 in the state of the tripod kit (16, 20). Further, even if the outer roller 26 is lowered in FIG. 15, the handling is further facilitated by setting so that the needle roller 24 does not disassemble due to interference with the boss 16a of the tripod 16.
[0041]
In the embodiment shown in FIG. 16, when the outer diameter of the outer needle retainer 22b of the inner roller 22 is φdo and the inner diameter of the outer roller 26 is φDi, the relationship φDi <φdo is set. In this embodiment, since the relationship φDi <φdo is set, the outer roller 26 is less likely to be separated from the inner roller 22 in the state of the tripod kit (16, 20), so that the handling is easy.
[0042]
【The invention's effect】
As described above, according to the present invention, it is possible to provide a tripod-type constant velocity universal joint that can reduce vibration of a vehicle, and that satisfies all of high strength, high durability, lightweight compactness, and low cost. .
[Brief description of the drawings]
FIG. 1a is a front view of a tripod,
b is a bb cross-sectional view of FIG. 1a.
FIG. 2 is a cross-sectional view of a tripod type constant velocity universal joint.
FIG. 3 is a longitudinal sectional view of a tripod type constant velocity universal joint.
FIG. 4 is a partially enlarged view of the tripod kit in FIG. 2;
FIG. 5 is a cross-sectional view for explaining how to assemble the tripod kit.
FIG. 6A is a side view of a trunnion journal,
b is a cross-sectional view of the trunnion journal of FIG.
FIG. 6C is a partially enlarged view of FIG. 6B.
FIG. 7a is a side view of a trunnion journal,
b is an enlarged cross-sectional view of a contact portion between the trunnion journal and the inner roller.
FIG. 8A is a front view of a trunnion journal,
b is a side view of the trunnion journal,
FIG. 8C is an enlarged view of a portion c in FIG.
FIG. 9 is a cross-sectional diagram of a contact portion between a trunnion journal and an inner roller.
FIG. 10 is a sectional view similar to FIG. 5;
FIG. 11A is a sectional view of an inner roller,
b is a bottom view of the inner roller shown in FIG. 11a.
FIG. 12 is a cross-sectional view of the tripod kit fixed to a rotating shaft.
FIG. 13 is a partial sectional view of the tripod kit.
FIG. 14 is a partial sectional view of a tripod kit.
FIG. 15 is a partial sectional view of a tripod kit.
FIG. 16 is a partial sectional view of a tripod kit.
FIG. 17 is a perspective view of a tripod type constant velocity universal joint showing a conventional technique.
18 is a longitudinal sectional view of the tripod type constant velocity universal joint shown in FIG. 17;
FIG. 19A is a sectional view showing another conventional technique,
b is a cross-sectional view of the trunnion journal in FIG. 19a.
[Explanation of symbols]
11 tripod type constant velocity universal joint
14 Housing
14a groove
14b Guide surface
14c Guide shoulder
16 tripods
16a boss
16c escape (chamfer)
16b trunnion journal
16d forging parting line
16e escape
20 Roller assembly
22 Inside roller
22a Inner needle retainer
22b Outer needle retainer
24 Needle roller
25a Inner needle retainer
25b Outer needle retainer
26 Outer roller
26a Inner needle retainer
26b Outer needle retainer

Claims (10)

A hollow cylindrical housing fixed to the end of the first rotating shaft, which is formed at one end in the axial direction and has a concave groove extending in the axial direction at a position equally divided in the circumferential direction of the inner peripheral surface,
A boss fixed to the end of the second rotating shaft, and a tripod consisting of a trunnion journal whose spherical end protrudes radially from a circumferentially equally-divided position of the boss,
A roller assembly including an inner roller whose inner peripheral surface is swingably fitted to the spherical outer peripheral surface of the trunnion journal, and an outer roller supported on the outer peripheral surface of the inner roller via a needle roller so as to be rotatable and axially movable. Has,
A guide surface for receiving the load by contacting the outer roller with the outer peripheral surface of the outer roller, and a guide shoulder surface for guiding the outer roller in the axial direction of the housing; Consisting of
When assembling the roller assembly into the trunnion journal, in the tripod type constant velocity universal joint in which the roller assembly is inclined and assembled in the joint axial direction,
A tripod-type constant velocity universal joint, wherein a root portion of the tripod journal has a non-circular cross section whose diameter in the joint circumferential direction is larger than diameter in the joint axial direction. The tripod type constant velocity universal joint according to claim 1, wherein the outer diameter of the tripod boss on the end side of the second rotating shaft is large. 3. A tripod-type constant velocity freely according to claim 1 or 2, wherein a relief is provided partially along a forging parting line of the trunnion journal so that a projection height of the parting line is equal to or less than a spherical diameter. Fittings. The tripod constant velocity universal joint according to any one of claims 1 to 3, wherein a cross-sectional shape of the trunnion journal in a torque load region has a substantially spherical shape. 5. The tripod type according to claim 4, wherein the radius R of the two spherical surfaces of the trunnion journal is set in the range of r / 2 <R <r, where r is the radius of curvature of the spherical inner peripheral surface of the inner roller. Constant velocity universal joint. Assuming that the angle at which the roller assembly starts to separate from the trunnion journal is θ1, after setting the rotation shaft to the tripod kit, if the roller assembly is tilted to an angle θ2 (θ2 <θ1), it is set so as to interfere with the rotation shaft. The tripod type constant velocity universal joint according to any one of claims 1 to 5, wherein 7. The tripod type constant velocity universal joint according to claim 1, wherein a needle retainer is integrally provided at at least one end of the inner peripheral surface of the outer roller. 7. The tripod type constant velocity universal joint according to claim 1, wherein a needle retainer is integrally provided at at least one end of the outer peripheral surface of the inner roller. 8. The tripod type constant velocity universal joint according to claim 7, wherein an inner diameter of a cylindrical inner peripheral surface of the outer roller at an inner diameter side end of the outer roller is smaller than an outer diameter of the inner roller. 9. The tripod type constant velocity universal joint according to claim 8, wherein an outer diameter of an end portion of the outer peripheral side of the cylindrical outer peripheral surface of the inner roller is larger than an inner diameter of the outer roller.

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