JP4350392B2 - Tripod type constant velocity universal joint - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The tripod type constant velocity universal joint according to the present invention is incorporated, for example, in a drive system of an automobile, and is used when a rotational force is transmitted at a constant angular velocity between rotating shafts existing on a non-linear line.
[0002]
[Prior art]
Tripod type constant velocity universal joints are widely used as a kind of constant velocity universal joints incorporated in the drive system of automobiles. For example, Japanese Laid-Open Patent Publication No. 62-233522 describes a tripod type constant velocity universal joint as shown in FIGS. This tripod type constant velocity universal joint 1 includes a hollow cylindrical housing 3 fixed to an end of a first rotating shaft 2 such as a drive shaft, and an end of a second rotating shaft 4 such as a wheel-side rotating shaft. It is comprised from the tripod 5 fixed to a 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 into three 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 rotating shaft 4 and a cylindrical trunnion journal 8 projecting in a radial direction from a circumferentially divided position of the boss 7. The 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 configured by fitting these rollers 9 into the concave grooves 6 of the housing 3. A pair of guide surfaces 6a constituting each concave groove 6 is an arcuate concave surface, and each roller 9 is supported between the pair of guide surfaces 6a so as to be able to roll and swing.
[0004]
When the tripod type constant velocity universal joint 1 configured as described above is used, for example, when the first rotary shaft 2 rotates, this rotational force is transferred from the housing 3 via the roller 9, the needle roller 10, and the trunnion journal 8 to the tripod. 5 is transmitted to the boss 7 and the second rotary shaft 4 is rotated. Further, when the center axis of the first rotating shaft 2 and the center axis of the second rotating shaft 4 do not coincide as shown in FIG. 18, that is, when the tripod constant velocity universal joint 1 takes an operating angle, As the rotary shafts 2 and 4 rotate, the trunnion journals 8 are displaced in the swinging direction about the tripod 5 as shown in FIGS. 17 and 18 with respect to the guide surface 6a of the corresponding concave groove 6. To do. At this time, the roller 9 supported by each trunnion journal 8 rolls on the guide surface 6 a of the concave groove 6 and is displaced in the axial direction of the trunnion journal 8. These movements ensure constant velocity between the first and second rotating shafts 2 and 4 as is well known.
[0005]
[Patent Document 1]
JP-A-62-233522 (first page, lower right column, line 14 to page 2, lower left column, line 17, FIG. 7, FIG. 8)
[Patent Document 2]
French Patent No. 2752890 (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 taken, each roller 9 performs a complicated motion. That is, each roller 9 moves along the guide surface 6 a while changing its direction in the axial direction of the housing 3, and is displaced in the axial direction of the trunnion journal 8. When each roller 9 performs such a complicated movement, the relative displacement between the outer peripheral surface of each roller 9 and the guide surface 6a is not necessarily performed smoothly, and a relatively large friction is generated between these two surfaces. As a result, in the case of the tripod type constant velocity universal joint having a structure as shown in FIGS. 17 and 18, an axial force of one rotation and tertiary is generated. Then, like the time of transmitting a large torque in a state of taking a large operating angle is built into the motor vehicle, it is known that vibration called Shi Yada occurs when significant.
[0007]
As a means for solving the above problems, French Patent No. 2752890 proposes a structure as shown in FIG. 19 has a structure in which the rollers (9a, 9b) are guided in parallel with the groove in the housing, and alignment 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 bus bar of the trunnion journal 8 is made smaller than the radius R of the trunnion journal 8, and the rollers (9a, 9b) are tilted in the circumferential direction of the joint with respect to the trunnion journal 8 as shown in FIG. By making the relationship of <φB hold and providing the flat surface portion 8a, spherical fitting is possible.
[0008]
However, in this case, it is necessary to make the radius of curvature rT of the trunnion journal 8 smaller than the radius of curvature of the inner spherical surface of the inner rollers 9a that are spherically fitted to each other, and there is a problem that the surface pressure increases. Even if the radius of curvature rT of the trunnion journal 8 is not reduced, it can be assembled by setting the spherical fitting clearance to be large. In this case, however, there is a problem that the rotation direction of the joint becomes large. In addition, since it is necessary to avoid interference between the root portion of the trunnion journal in the circumferential direction of the joint that receives torque load and the roller, there is a limit to increasing the neck diameter of the trunnion journal. Moreover, when a limit design is performed for the purpose of reducing the size and weight, the trunnion journal base portion in the joint circumferential direction that receives a torque load is likely to be the weakest strength portion of the trunnion journal, and it is difficult to ensure high strength.
[0009]
The object of the present invention is to eliminate the above-mentioned problems. That is, the present invention is a highly durable tripod type in which the surface pressure is reduced by spherical fitting while the clearance between the inner roller and the trunnion journal to be spherically fitted is reduced to keep the backlash in the rotational direction small. It is to achieve light weight, compactness and low cost while ensuring the strength under the trunnion journal in the fast universal joint.
[0010]
[Means for Solving the Problems]
The tripod type constant velocity universal joint of the present invention has an end of the first rotary shaft 12 which is open on one end side in the axial direction and has a groove 14a extending in the axial direction at a circumferential trisection position on the inner peripheral surface. A hollow cylindrical housing 14 fixed to the section;
A tripod 16 composed of a boss 16a fixed to the end of the second rotating shaft 13 and a trunnion journal 16b having a spherical end that protrudes in a radial direction from the circumferentially divided position of the boss 16a;
An inner roller 22 in which the spherical inner peripheral surface is swingably fitted to 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. A roller assembly 20 comprising:
The outer roller 26 is accommodated in the concave groove 14a of the housing 14 so that it can roll in the axial direction of the housing. The concave groove 14a is in contact with the outer peripheral surface of the outer roller 26, and the guide surface 14b and the outer roller 26 receiving the load And a guide shoulder surface 14c for guiding to
When the roller assembly is assembled into the trunnion journal, the tripod type constant velocity universal joint 11 assembled by tilting the roller assembly in the joint axial direction,
The root portion of the trunnion journal 16b has a noncircular cross section in which the diameter in the joint circumferential direction is larger than the diameter in the joint axial direction.
[0011]
Examples of the non-circular shape in which the diameter in the joint circumferential direction is larger than the diameter in the joint axial direction include an ellipse (see FIG. 1B) with the minor axis directed in the joint axial direction. By tilting the roller assembly in the plane including the joint axial direction and assembling to the trunnion journal, the interference relief for assembling the lower journal neck and the roller need only exist on the joint axial side of the lower journal neck. In addition, no interference escape for assembly is required on the joint circumferential direction side. In the case of such specifications, there is no interference escape at the position in the circumferential direction below the neck, 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 end of the second rotating shaft 13 of the boss 16a of the tripod 16 may be chamfered (16c), so that when the roller assembly 20 is inclined and assembled to the trunnion journal 16b, the roller The assembly 20 can be tilted more greatly, and torque transmission between the tripod 16 and the second rotary shaft 13 during assembly is mostly handled on the second rotary shaft non-end portion side in the boss 16a. Even if the end portion side of the second rotating shaft 13 of the boss 16a is greatly chamfered, the strength of the boss portion is not reduced.
[0013]
A relief 16e (FIGS. 6 and 8) may be provided partially along the forged parting line 16d of the trunnion journal 16b so that the convex height of the parting line is less than or equal to 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 clearance, 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 combines shea Yada reduction and high durability and low cost at the time of assembling the vehicle.
[0014]
The cross-sectional shape of the trunnion journal 16b in the torque load region may be a substantially dihedral shape (FIG. 9). In that 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 across the forging parting line 16d of the trunnion journal 16b. No worries.
[0015]
As a specific aspect of the substantially dihedral shape, when 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 in a range of r / 2 <R <r. You can list what you have set.
[0016]
When the angle at which the roller assembly 20 begins to separate from the trunnion journal 16b is θ1, the roller assembly 20 is mounted to the angle θ2 (θ2 <θ1) after the rotary shafts (13, 13a) are mounted on the tripod kit (16, 20). It can be set to interfere with the rotation axis (13, 13a) when tilted (FIG. 12). Here, a unit composed of 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, when the tripod 16 is assembled to the second rotating shaft 13 in the state of a unit comprising the tripod 16 and the roller assembly 20, that is, a tripod kit, and once the retaining ring 13a is attached, the retaining ring 13a or The tripod kit (16, 20) and the rotary shaft 4 are in a unit handling state and can be handled very easily because the inner roller 22 cannot interfere with the rotary shaft 13 and can not tilt to the angle θ1 at which the inner roller 22 is separated from the trunnion journal 16b. 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 constituted by only three bodies 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 constituted by only three bodies 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 joint inner diameter side end of the cylindrical inner peripheral surface of the outer roller 26 can be made smaller than the outer diameter do of the inner roller 22 (Di <do) (FIG. 15). By adopting such a configuration, the outer roller 26 is hardly disassembled from the inner roller 22 in the state of the tripod kit (16, 20), so that the handling becomes easy.
[0020]
The outer diameter do of the joint 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 adopting such a configuration, the outer roller 26 is hardly disassembled from the inner roller 22 in the state of the tripod kit (16, 20), so that the handling becomes easy.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. First, the basic configuration will be described with reference to FIGS. 2 and 3. The tripod type constant velocity universal joint 11 includes a hollow cylindrical housing 14 fixed to an end portion of a first rotating shaft 12 such as a drive shaft, a wheel, And a tripod 16 fixed to the end of the second rotary shaft 13 such as a side rotary shaft.
[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 equally divided into three in the circumferential direction on the inner peripheral surface. Each concave groove 14a is recessed radially outward from the inner peripheral surface of the housing 14, and a pair of guide surfaces 14b facing each other in the circumferential direction and both guides positioned on the outer side in the radial direction of the housing. It is comprised by the bottom face which connects the surface 14b. The pair of guide surfaces 14 b provide a track for rolling an outer roller 26 (described later) in the axial direction of the housing, and transmits torque to and from the outer roller 26. 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 plays a role of maintaining a posture parallel to the axial direction of the housing and smoothly rolling 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 16 a is fixed to the end of the second rotating shaft 13. For example, a spline shaft formed on the second rotating shaft 13 and a spline hole formed on the boss 16a are fitted and positioned by the retaining ring 13a. The trunnion journal 16b protrudes in the radial direction from the circumferentially divided position of the boss 16a. The end of each trunnion journal 16b has a spherical shape.
[0024]
Each trunnion journal 16 b supports a roller assembly 20. The roller assembly 20 is a double roller type including an inner roller 22 and an outer roller 26 that are relatively rotatable via a needle roller 24. The inner peripheral surface of the inner roller 22 has a spherical shape with 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. In this way, the spherical inner peripheral surface of the inner roller 22 is supported in a freely swingable manner 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 out, an annular needle retainer 25a is disposed on both ends of the needle roller 24, and a retaining ring 25b is mounted on a retaining ring groove formed on the inner peripheral surface of both ends of the outer roller 26, thereby the needle retainer. 25a is retained (see FIG. 4).
[0026]
The outer roller 26 is accommodated in the concave groove 14 a of the housing 14. The pair of guide surfaces 14b constituting each concave groove 14a has an arc shape 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 supported between the pair of guide surfaces 14b so as to roll freely.
[0027]
When the tripod type constant velocity universal joint configured as described above is used, for example, when the first rotary shaft 12 rotates, this rotational force is generated 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 rotary shaft 13 is rotated. Further, as shown in FIG. 3, when the central axis of the first rotary shaft 12 and the central axis of the second rotary shaft 13 do not coincide with each other, in other words, when the operating angle is taken, the rotation of both rotary shafts is accompanied. Each trunnion journal 16b is displaced in a swinging direction about the tripod 16 with respect to the guide surface 14b of the corresponding concave groove 14a. At that time, the outer roller 26 supported by the trunnion journal 16b rolls on the guide surface 14b of the concave groove 14a and is displaced in the axial direction of the trunnion journal 16b. As is well known, these movements ensure constant velocity between the first and second rotating shafts 12 and 13.
[0028]
As shown in FIG. 1, the base portion of the tripod journal 16b has a non-circular cross section in which the 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 minor axis is oriented in the joint axial 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 indicated by reference numeral 16c in the figure, a large chamfer is provided only on the end portion side (the right side in FIG. 3 and the left side in FIG. 5) of the boss 16a of the tripod 16 on the second rotating shaft 13. This large chamfer functions 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 greatly inclined as shown by an imaginary line in FIG. To do. The roller assembly 20 (the inner roller 22 thereof) and the trunnion journal 16b interfere with each other only in two opposing positions in the direction in which the torque load acts (direction perpendicular to the paper surface of FIG. 5). Assembling becomes possible by pushing in while elastically deforming.
[0030]
The interference relief between the trunnion journal 16b and the roller assembly 20 may be present in the lower portion of the trunnion journal neck in the joint axial direction, and is not required in the lower portion of the trunnion journal in the joint circumferential direction. This specification eliminates the need for interference relief at the position in the circumferential direction below the neck that tends to be the maximum stress position when receiving a torque load, so it is possible to improve the strength and make a more compact tripod constant velocity universal joint. It becomes. Furthermore, two planes (outside the load range) perpendicular to the position where the trunnion journal 16b receives the torque load may be provided to escape.
[0031]
According to the above structure, in the high performance type tripod type constant velocity universal joint, torque is transmitted between the spherical inner peripheral surface of the inner roller 22 and the spherical trunnion journal 16b.・ Because it is advantageous in terms of durability, the trunnion journal 16b has improved neck strength, so 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 with the spherical inner peripheral surface of the inner roller 22, but the raised portion of the forged parting line 16d is shown by a broken line in FIG. A relief 16e is partially provided along the forging parting line 16d so as not to retreat inward from the spherical diameter shown in FIG. For this reason, it becomes possible to omit the raised part removal process of the forging parting line 16d, and it can be used with the cold-formed surface, and the cost can be reduced. In this case, the relief area 16e cannot receive a load, so the load area is reduced. However, since the trunnion journal 16b and the inner roller 22 are subjected to a load in a wide range by spherical fitting, a part of the load range is reduced. Even so, a sufficient load capacity can be maintained. Further, when the relief 16e is provided, the effect of reducing interference when the inner roller 22 is assembled to the trunnion journal 16b is obtained compared to the case without the relief 16e, and the elastic deformation amount of the inner roller 22 is reduced. Can be eliminated.
[0033]
Various specific embodiments of the relief 16e are conceivable. As the simplest example, as shown in FIG. 7A, a part of a spherical surface is cut off to form a flat surface. However, when the relief portion is provided by simply deleting a part of the spherical surface, the width dimension A of the relief portion is increased and the area subjected to the load is reduced. Therefore, for example, as shown in FIGS. 8A to 8C, a relief 16e having an arc shape can be formed in the longitudinal section of the trunnion journal 16b. In the case of this embodiment, there is an advantage that the relief portion width dimension B is small and the area under load is increased. However, in both examples, a contact state as shown in FIG. 7B occurs, stress concentration occurs at the edge portion, and early peeling occurs. Even if the corner R is set in the edge portion, 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 dihedral. 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 a 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 portion between the trunnion journal 16b and the inner roller 22 is located at two symmetrical positions across the forged parting line 16d of the trunnion journal 16b.
[0035]
Embodiment shown in FIG. 10, when the angle of tilting when assembling the roller assembly 20 (the inner roller 22) to the trunnion journal 16b and the theta, trunnion journal including a raised outer diameter portion of the forged parting line 16d The maximum projected diameter φD from the angle θ direction of 16b is set to be smaller than the fitting insertion side inner diameter φd of the inner roller 22.
[0036]
In the embodiment shown in FIG. 11, a notch is partially provided on the inner diameter of the inner roller 22 on the insertion side, the inner diameter of the notch is φd2, and the trunnion journal 16b (including the forged parting line 16d) is in the angle θ direction. When the maximum projected diameter is φD2, φD2 <φd2. As a result, when the roller assembly 20 is assembled to the trunnion journal 16b, the inner roller 22 can be assembled without being elastically deformed. Therefore, according to this embodiment, it is possible to omit the forging parting line removing step and the press-fitting step when assembling the roller assembly 20 to the trunnion journal 16b.
[0037]
In the embodiment shown in FIG. 12, when the roller assembly 20 is tilted 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. The dimension is set so 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, when the tripod 16 is assembled to the second rotating shaft 13 in the state of a unit comprising the tripod 16 and the roller assembly 20, that is, a tripod kit, and once the retaining ring 13a is attached, the retaining ring 13a or A unit in which the tripod kit (16, 20) and the rotating shaft 13 are not disassembled because the inner roller 22 cannot be tilted to the angle θ1 at which the inner roller 22 is separated from the trunnion journal 16b by interfering with the second rotating shaft 13. It becomes a handling state and handling becomes easy.
[0038]
In the embodiment shown in FIG. 13, needle retainers 26 a and 26 b are integrally formed by providing protrusions at both ends of the cylindrical inner peripheral surface of the outer roller 26. Both needle retainers 26a and 26b can be integrated with the outer roller 26 as shown, or only one of the inner and outer rollers can be integrated with the outer roller 26, and the other can be separate.
[0039]
In the embodiment shown in FIG. 14, needle retainers 22 a and 22 b are integrally formed by providing protrusions on both ends of the cylindrical outer peripheral surface of the inner roller 22 over the entire circumference. Needle retainer 22a, 22b, in addition to an integral with both the inner roller 22 as illustrated, and inside or Either integral with the side roller 22 only of the outer and the other may be separate bodies.
[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, a relationship of φDi <φdo is set. In this embodiment, since the relationship of φDi <φdo is set, the outer roller 26 is difficult to be disassembled from the inner roller 22 in the tripod kit (16, 20). In addition, even when the outer roller 26 is lowered in FIG. 15, handling is further facilitated by setting so that the needle roller 24 does not disassemble due to interference with the boss 16 a portion 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, a relationship of φDi <φdo is set. In this embodiment, since the set relationship φDi <φdo, in the state of the tripod kit (16, 20), Ri outer roller 26 is hardly separated from the inner roller 22, it becomes easy to handle.
[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 vehicle vibration and satisfy all of high strength, high durability, light weight, compactness, and low cost. .
[Brief description of the drawings]
1A is a front view of a tripod, and FIG. 1B is a cross-sectional view taken along line bb 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.
4 is a partially enlarged view of the tripod kit in FIG. 2. FIG.
FIG. 5 is a cross-sectional view for explaining the assembly procedure of the tripod kit.
6A is a side view of a trunnion journal, FIG. 6B is a cross-sectional view of the trunnion journal of FIG. 6A, and FIG. 6C is a partially enlarged view of FIG.
7A is a side view of the trunnion journal, and FIG. 7B is an enlarged cross-sectional view of a contact portion between the trunnion journal and the inner roller.
8A is a front view of a trunnion journal, b is a side view of the trunnion journal, and c is an enlarged view of a portion c in FIG. 8A.
FIG. 9 is a cross-sectional diagram of a contact portion between a trunnion journal and an inner roller.
10 is a cross-sectional view similar to FIG.
11A is a cross-sectional view of the inner roller, and b is a bottom view of the inner roller shown in FIG. 11A.
FIG. 12 is a cross-sectional view of the tripod kit in a state of being fixed to a rotating shaft.
FIG. 13 is a partial cross-sectional view of a tripod kit.
FIG. 14 is a partial cross-sectional view of a tripod kit.
FIG. 15 is a partial cross-sectional view of a tripod kit.
FIG. 16 is a partial cross-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 of FIG.
19A is a cross-sectional view showing another conventional technique, and FIG. 19B 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 Concave groove 14b Guide surface 14c Guide shoulder surface 16 Tripod 16a Boss 16c Escape (chamfer)
16b trunnion journal 16d forged parting line 16e relief 20 roller assembly 22 inner 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 that is fixed at the end of the first rotating shaft and that is formed at one end side in the axial direction and has a concave groove extending in the axial direction at a circumferentially equally divided position on the inner peripheral surface;
A tripod composed of a boss fixed to the end of the second rotating shaft and a trunnion journal having a spherical end that protrudes in a radial direction from the circumferentially divided position of the boss;
A roller assembly comprising an inner roller in which a spherical inner peripheral surface is swung freely on a spherical outer peripheral surface of a trunnion journal, and an outer roller supported on the outer peripheral surface of the inner roller so as to be rotatable and axially movable via a needle roller And
The outer roller is accommodated in a groove in the housing so that it can roll in the axial direction of the housing, the groove contacts the outer peripheral surface of the outer roller and receives a load, and the guide shoulder surface guides the outer roller in the housing axial direction. Consists of
When installing the roller assembly in the trunnion journal, in the tripod type constant velocity universal joint that is assembled by tilting the roller assembly in the joint axial direction,
A tripod type constant velocity universal joint, characterized in that the root of the trunnion journal has a non-circular cross section whose diameter in the joint circumferential direction is larger than the diameter in the joint axial direction.   2. The tripod constant velocity universal joint according to claim 1, wherein an outer diameter of the tripod boss on the end portion side of the second rotating shaft is chamfered greatly.   The tripod type constant velocity free according to claim 1 or 2, characterized in that along the forged parting line of the trunnion journal, a relief is partly provided so that the convex height of the parting line is equal to or less than the spherical diameter. Fittings.   The tripod type constant velocity universal joint according to any one of claims 1 to 3, wherein the cross-sectional shape of the trunnion journal in the torque load region is a substantially bispherical 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 a 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.   When the angle at which the roller assembly begins to separate from the trunnion journal is θ1, the roller assembly is set to interfere with the rotation shaft when the roller assembly is tilted to an angle θ2 (θ2 <θ1) after the rotation shaft is mounted on the tripod kit. The tripod type constant velocity universal joint according to any one of claims 1 to 5.   The tripod type constant velocity universal joint according to any one of claims 1 to 6, wherein a needle retainer is integrally provided on at least one end of the inner peripheral surface of the outer roller.   The tripod type constant velocity universal joint according to any one of claims 1 to 6, wherein a needle retainer is integrally provided on 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 joint inner diameter side end portion of a cylindrical inner peripheral surface 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 a joint outer diameter side end portion of a cylindrical outer peripheral surface of the inner roller is larger than an inner diameter of the outer roller.

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