JPH11336783A - Universal uniform coupling - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve lubricating performance of a sliding surface of a shaft part and a torque transmission member. SOLUTION: A recessed part 16C to hold grease is formed on an outer peripheral surface 16 of a trunnion 15 in a universal uniform coupling having a cylindrical outer race 10 and a shaft 8 arranged inside of the outer race 10, furnished with a plural number of grooves 11 formed on an inner periphery of the outer race 10, a plural number of the trunnions 15 formed on an outer periphery of a tripod member 14 of the shaft 8 and a ring roller assembly body 17 respectively installed on an outer periphery of each of the trunnions 15 and free to move in the longitudinal direction of each of the grooves 11 and constituted so that a plural number of the trunnions 15 and each of the roller assembly bodies 17 are free to relatively move in a height direction of each of the trunnions 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a constant velocity universal joint arranged on a torque transmission path of a vehicle.

[0002]

2. Description of the Related Art Generally, when two members are arranged in a torque transmission path of a vehicle, and the two members are connected with a predetermined operating angle, the two members are connected by a constant velocity universal joint. Sometimes. This constant velocity universal joint includes a Zeppa type joint, a tripod type joint, a cross groove type joint, and a double offset type joint. A tripod joint is used at a portion where the amount of movement between two members in the axial direction is large, such as a differential side of a front drive shaft of a vehicle or a differential side of a rear drive shaft. Examples of such tripod type joints are disclosed in JP-A-7-103251, JP-A-9-310723 and JP-A-54-103723.
No. 69643.

The tripod type joint described in these publications has a cylindrical outer member rotatable about a first axis and a tubular outer member disposed inside the outer member and in a plane including the first axis. An inner member rotatable about a second axis that is arranged. In addition, three grooves extending in the first axis direction are formed at regular intervals on the inner periphery of the outer member in the circumferential direction. Further, three shaft portions are formed from the outer periphery of the inner member toward the three grooves. An annular torque transmitting member that is movable in the longitudinal direction along each groove is attached to the outer periphery of each shaft.

In the above-mentioned tripod type joint, for example, the torque of the outer member is transmitted to the inner member via the torque transmitting member. On the other hand, grease is sealed inside the outer member, and the sliding surface between the groove of the outer member and the torque transmitting member, and the sliding surface between each torque transmitting member and each shaft portion are lubricated with grease. .

[0005]

In the tripod joint described in the above publication, an arc-shaped portion is formed on the inner peripheral surface of the torque transmitting member in a plane perpendicular to the center line thereof. Further, an arc-shaped portion is formed on the outer peripheral surface of the shaft portion in a plane orthogonal to the center line of the shaft portion. The transmission of torque is performed via a contact point between the two arc-shaped portions.

Here, the radius of the arc-shaped portion of the torque transmitting member and the radius of the arc-shaped portion of the shaft are set to be the same. For this reason, the arc-shaped portion of the torque transmitting member and the arc-shaped portion of the shaft portion are in line contact with each other over the entire circumferential direction.
Therefore, it is difficult for grease to intervene between the sliding surfaces of the arc-shaped portion of the torque transmitting member and the arc-shaped portion of the shaft portion, and the frictional resistance of the sliding region between the two arc-shaped portions has increased. As a result, heat generation, wear, flaking, adhesion and the like of the torque transmitting member and the shaft portion may occur, and the durability of the tripod type joint may be reduced.

The present invention has been made in view of the above circumstances, and has as its object to provide a constant velocity universal joint capable of improving lubrication performance on a sliding surface between a shaft portion and a torque transmitting member.

[0008]

In order to achieve the above object, a first aspect of the present invention is to provide a tubular outer member rotatable about a first axis, and disposed inside the outer member. And an inner member rotatable about a second axis disposed in a plane including the first axis, and formed at predetermined intervals in a circumferential direction on an inner periphery of the outer member, and A plurality of grooves extending in the first axial direction;
A plurality of shaft portions protrudingly formed on the outer periphery of the inner member; and an annular torque transmitting member attached to the outer periphery of each shaft portion and abutting on each of the grooves and movable in the longitudinal direction of each of the grooves. A constant velocity universal joint in which the plurality of shafts and the torque transmitting members are configured to be relatively movable in the longitudinal direction of the shafts, and a lubricant is sealed inside the outer member. , A concave portion for holding the lubricant is formed on at least one of an outer peripheral surface of the shaft portion and an inner peripheral surface of the torque transmitting member.

A second aspect of the present invention is characterized in that, in addition to the configuration of the first aspect, a plurality of the concave portions are arranged at predetermined intervals in a circumferential direction.

A third aspect of the present invention is characterized in that, in addition to the configuration of the first aspect, the concave portion is formed in an arc shape along a circumferential direction.

According to a fourth aspect of the present invention, in addition to the configuration of the first aspect, the concave portion is formed in a spiral shape.

According to a fifth aspect of the present invention, in addition to the first or third aspect, a plurality of the shaft portions are arranged at predetermined intervals in a longitudinal direction of the shaft portion or in an axial direction of the torque transmitting member. Features.

According to the present invention, the outer peripheral surface of the shaft portion and the inner peripheral surface of the torque transmitting member are in contact with each other, and the torque is transmitted through each contacting portion, so that the torque is transmitted between the outer member and the inner member. Is transmitted. Since the concave portion is formed on at least one of the outer peripheral surface of the shaft portion and the inner peripheral surface of the torque transmitting member, the lubricant is retained in the concave portion, and the lubrication between the sliding surface of the shaft portion and the torque transmitting member is performed. Performance is improved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 2 is a conceptual plan view of a front wheel drive vehicle 1 to which the constant velocity universal joint of the present invention is applied. That is, the front of the front wheel drive vehicle 1 is provided with the engine 2
And a transmission 3 for converting torque output from the engine 2, and a differential 4 connected to an output side of the transmission 3. A pair of front drive shafts 5 are connected to the output side of the differential 4, and the pair of front drive shafts 5 are connected to the front wheels 6 respectively. That is,
The pair of front drive shafts 5 are arranged in the width direction of the front wheel drive vehicle 1.

The pair of front drive shafts 5 includes a tripod joint 7, which is a constant velocity universal joint, a shaft 8, and another constant velocity universal joint 9. That is, the tripod joint 7 is provided at one end of the shaft 8, and the constant velocity universal joint 9 is provided at the other end of the shaft 8. And one tripod joint 7
Are connected to the differential 4 side, and the other constant velocity universal joint 9 is connected to the front wheel 6 side. The constant velocity universal joint 9 is exemplified by a bar field type joint. (First embodiment)

The construction of the tripod joint 7 connected to the right wheel 6 of FIG. 2 is shown in FIG. FIG. 1 is a front cross-sectional view showing a tripod joint 7, in which a second axis B1 of a shaft 8 and an outer race 1 are shown.
A predetermined operating angle (connection angle) θ1 is set to the first axis A1 of 0. FIG. 3 is a partial side end view of the tripod joint 7. In FIG. 3, the first axis A1 of the outer race 10 and the second axis of the shaft 8 are positioned substantially linearly for convenience. A tripod joint 7 is shown corresponding to the state. In FIG. 3, the shaft 8 is omitted for convenience.

FIG. 4 shows a main part of the tripod type joint 7 corresponding to FIG. The tripod joint 7 connected to the left wheel 6 in FIG.
Since it is configured to be plane-symmetric with the tripod joint 7 shown in FIGS. 1 and 3, the description thereof is omitted.

The tripod type joint 7 has an outer race 10 having a bottomed cylindrical shape, and a shaft 8 having one end arranged inside the outer race 10. As shown in FIG. 1, the outer race 10 is configured to be rotatable about a first axis A1, and the shaft 8 is configured to be rotatable about a second axis B1. A spline shaft (not shown) centering on the first axis A1 is integrally formed on the bottom of the outer race 10. The differential 4 is a side gear (not shown).
And the spline shaft and the side gear are connected. Further, three grooves 11 extending in the first axial direction are formed on the inner periphery of the outer race 10. The grooves 11 are spaced at equal intervals in the circumferential direction,
They are arranged at intervals of 20 degrees.

Each groove 11 has a bottom surface 12 and an inner wall surface 13. The bottom surface 12 is configured substantially parallel to the first axis A1, and a pair of inner wall surfaces 13 are connected to both sides of the bottom surface 12 in the width direction. In a plane orthogonal to the first axis A <b> 1, the shape of the pair of inner wall surfaces 13 is curved so as to protrude outside the outer race 10. That is, the pair of inner wall surfaces 13 are configured to be mutually plane-symmetric.

Further, one end of the shaft 8 is disposed inside the outer race 10, and an annular tripod member 14 is spline-fitted to the outer periphery of the end of the shaft 8 on the outer race 10 side. Shaft 8
, Two snap rings 15A are attached, and the shaft 8 and the tripod member 14 are positioned in the second axial direction of the shaft 8 by the snap rings 15A.

Then, on the outer periphery of the tripod member 14,
Three trunnions 15 projecting outward are formed. The trunnions 15 are arranged at equal intervals in the circumferential direction of the tripod member 14, specifically, at 120 ° intervals. Each trunnion 15 is formed in a columnar shape. The protrusion amount of each trunnion 15 in the radial direction of the tripod member 14 is such that the outer peripheral surface of each trunnion 15 is
It is set to a value that reaches between the pair of inner wall surfaces 13.

Further, as shown in FIG.
Is formed as an arc surface on which the outer peripheral surface 16 projects outward in a plane including the first center line C1 of the trunnion 15. Specifically, the center of curvature (not shown) of the outer peripheral surface 16 is set on the first center line C1. Next, the shape of the outer peripheral surface 16 in a first plane orthogonal to the first center line C1 of the trunnion 15 will be described with reference to FIG.

On the outer periphery of the trunnion 15, two arc-shaped portions 16A and 16B are formed in the circumferential direction. The respective lengths of the arc-shaped portions 16A and 16B in the circumferential direction are as follows:
They are set to less than half of the entire circumference of the outer peripheral surface 16 and are set to be substantially the same as each other. This arc-shaped portion 16
A and 16B are configured based on the same center of curvature (not shown), and the radius of curvature of the arc-shaped portions 16A and 16B is set to be the same.

Further, a plane (not shown) passing through the center in the longitudinal direction of the arc-shaped portions 16A and 16B is set to be in a state orthogonal to the second center line B1. That is,
The center of the arc-shaped portions 16A and 16B in the length direction is the groove 11
Is formed at a position opposed to. In other words, when torque is transmitted between the outer race 10 and the shaft 8, the center of the arc-shaped portions 16A and 16B in the longitudinal direction is provided in a torque transmission surface set orthogonal to the first axis A1. Is configured to be located.

In the arc-shaped portions 16A and 16B, recesses (grooves or depressions) 16C are provided at predetermined intervals in the circumferential direction.
Are formed in a row. The recess 16C is configured to hold grease, which will be described later.
Has a substantially circular side shape. A flat surface 16 is provided between the arc-shaped portions 16A and 16B.
D are formed respectively. Each flat surface 16D is arranged in the longitudinal direction of the groove 12. The side surface shape of each flat surface 16D is substantially circular as shown in FIG.

According to the above configuration, the trunnion 1 is located in the first plane orthogonal to the first center line C1 of the trunnion 15.
The shape of the outer peripheral surface 16 of 5 is set to a substantially elliptical shape, in other words, a track shape. That is, the first center line C
1, and the shape of the outer peripheral surface 16 is configured to be plane symmetric with a plane passing through the center of the two flat surfaces 16D separated.

Further, an annular roller assembly 17 is attached to the outer periphery of each trunnion 15. The roller assembly 17 is formed annularly around the second center line C2. The roller assembly 17 includes an inner ring 18, a needle 19, and an outer roller 20.
And a snap ring 21. The inner ring 18 is fitted on the outer periphery of the trunnion 15.

The inner ring 18 is formed in a cylindrical shape, and as shown in FIG. 3, the length of the inner ring 18 in the second center line direction is set substantially equal to the amount of protrusion of the trunnion 15. Next, the shape of the inner ring 18 in a second plane orthogonal to the second center line C2 will be described with reference to FIG. FIG. 4 is a plan view corresponding to a state in which the first center line C1 of the trunnion 15 and the second center line C2 of the inner ring 18 are linearly located. The second plane is in the same state.

The shape of the inner peripheral surface 22 of the inner ring 18 is a perfect circle in the second plane. Further, the radius of the inner peripheral surface 22 is equal to the arc-shaped portions 16A, 16A
B is set slightly larger than each radius. That is,
The trunnion 15 and the inner ring 18 are relatively movable in the length direction of the trunnion 15 in a state of being in line contact with each other in the circumferential direction. A gap D1 is formed between each flat surface 16D and the inner peripheral surface 22.

The outer roller 20 is arranged outside the inner ring 18, and the outer roller 20 and the inner ring 18 are arranged concentrically. Furthermore, a plurality of needles 19 are arranged between the inner ring 18 and the outer roller 20. The inner ring 18 and the outer roller 20 are configured to be relatively rotatable via the plurality of needles 19.

Further, two annular grooves 23 are formed on the inner peripheral surface of the outer roller 20. The snap ring 21 is attached to each annular groove 23,
The inner diameter of the snap ring 21 is set to a value smaller than the outer diameter of the inner ring 18 and larger than the inner diameter of the inner ring 18. The inner ring 18 and the plurality of needles 19 are arranged between the two snap rings 21. Thus, the inner ring 18
And the outer roller 20 are two snap rings 2
1, the inner ring 18 and the outer roller 20 are positioned and fixed in the second center line direction.

The outer roller 20 is formed in an annular shape, and a curved surface 24 is formed on the outer periphery of the outer roller 20. The curved surface 24 has a center of curvature (not shown) set in a second plane including the second center line C1 of the outer roller 20. And outer roller 2
It is curved so as to protrude toward the outside of zero. Also, the curved surface 24 and the inner wall surface 13 of the groove 11 are in contact with each other at two points in the width direction of the inner wall surface 13, and the outer roller 20 is movable in the longitudinal direction of the groove 11. The shape and dimensions of the inner surface 24 and the inner surface 13 are set.

The trunnion 15 and the roller assembly 17
Is configured as described above, the roller assembly 1
7 is capable of pivoting and turning relative to the trunnion 15. Actually, since the roller assembly 17 is disposed in the groove 11, the roller assembly 17
5 can swing (swing) in a plane including the first center line C1. Further, the roller assembly 17 and the trunnion 15 are relatively movable in a first center line direction of the trunnion 15.

Further, one end of a bellows-shaped boot 25 is fixed to the outer periphery of the open end side of the outer race 10, and the other end of the boot 25 is fixed to the shaft 8. Thus, the inside of the outer race 10 is sealed in a liquid-tight manner by the boot 25, and grease (not shown) is sealed as a lubricant in the sealed space L1.

Next, the metal material forming the tripod joint 7 will be described. The outer race 10 is made of a material such as carbon steel or chrome steel, the shaft 8 is made of a material such as carbon steel or boron steel, and the tripod member 14 is made of a material such as chrome steel. The outer roller 20 and the inner ring 18 are made of a material such as bearing steel or chrome steel, and the needle 19 is made of a material such as bearing steel.

Here, the correspondence between the configuration of the embodiment and the configuration of the present invention will be described. The outer race 10 corresponds to the outer member of the present invention, and the tripod member 14 and the shaft 8 correspond to the inner member of the present invention. The trunnion 15 corresponds to the shaft of the present invention, and the roller assembly 17
Correspond to the torque transmitting member of the present invention.

Next, a part of the manufacturing process of the tripod member 14 will be described. First, a metal material is cold-forged by a mold to produce a rough material of the tripod member 14, and a tripod of the rough material is cut by a drill to form a recess 16C.

Further, the traveling operation of the front wheel drive vehicle 1 shown in FIG. 2 will be described. The torque output from the engine 2 is transmitted to each front drive shaft 5 via a transmission 3 and a differential 4. Specifically, the torque output from the differential 4 causes the outer race 10 to rotate in a predetermined direction. The torque of the outer race 10 is transmitted to the shaft 8 via the roller assembly 17 and the tripod member 14.
More specifically, the inner peripheral surface 22 of the inner roller 18
And the torque is transmitted via a contact area with one of the arc-shaped portions 16A and 16B of the trunnion 15. 2
The outer race 10 and the shaft 8 determine which of the two arc-shaped portions 16A and 16B transmits torque.
Is determined by the direction of rotation of.

As described above, the first axis A1 and the second axis B
1 and the predetermined operating angle θ1, the roller assembly 17 moves in the longitudinal direction of the groove 11 with the rotation of the outer race 10, and the roller assembly 17 and the trunnion 15 The roller assembly 17 swings relative to the trunnion 15 by moving relative to one center line. By these operations, the inner peripheral surface 22 of the inner roller 18 and the arc-shaped portion 16 of each tripod 15 are located within the torque transmission surface set orthogonal to the first axis A1.
A, 16B, the contact point is set, and the outer race 10
And the rotation of the shaft 8 is maintained at a constant speed. Thus, the torque of the shaft 8 is transmitted to the front wheels 6, and the front wheel drive vehicle 1 runs.

When torque is transmitted between the outer race 10 and the shaft 8, the trunnion 15
When the entire roller assembly 17 rolls in the groove 11 integrally based on conditions such as the frictional force between the outer roller 20 and the inner ring 1,
8 may move relative to each other via the rolling element 19, and only the outer roller 20 may roll in the groove 11. And
In this embodiment, any of the above cases is included in the rolling of the roller assembly 17. In addition, while the front wheel drive vehicle 1 is traveling, the operating angle θ1 fluctuates depending on conditions such as the vertical movement of the front wheels 6.

On the other hand, the sliding surface between the outer roller 20 and the groove 11 is lubricated by the grease sealed in the space L1. Further, as shown in FIG. 1, when the first center line C1 and the second center line C2 intersect at a predetermined angle, the arc-shaped portions 16A and 16B of the trunnion 15 and the inner peripheral surface of the inner roller 18 are formed. A gap is formed between the grease 22 and grease. Since the grease that has entered the gap is held by each recess 16C, the sliding surface between the trunnion 15 and the inner roller 18, specifically, the arc-shaped portions 16A and 16 that contribute to the transmission of torque.
The lubrication performance of the contact portion between B and the inner peripheral surface 22 is improved, and the frictional resistance is suppressed. Therefore, heat generation, abrasion, flaking, adhesion, and the like on the sliding surface between the trunnion 15 and the inner roller 18 are suppressed, and the durability of the tripod joint 7 is improved.

As a result, the outer peripheral surface 16 of the trunnion 15
Alternatively, the inner peripheral surface 22 of the inner roller 18 does not need to be subjected to low-friction coating such as application of a solid lubricant such as molybdenum disulfide, or surface treatment such as lubricite. Time can be reduced, and manufacturing costs can be reduced.

By the way, when the roller assembly 17 is moving in the longitudinal direction of the groove 11, the outer race 10 is in contact with the curved surface 24 of the outer roller 20 and the inner wall surface 13 of the groove 11. A frictional force acts in the first axis direction. In the tripod-type joint 7, the torque is transmitted by the three roller assemblies 17, so that the forcible force of three cycles, that is, three rotations, during one rotation of the shaft 8 and the outer race 10.
The next forcing force (in other words, the fluctuation component of the induced thrust force) acts on the outer race 10.

On the other hand, when the trunnion 15 and the inner roller 18 relatively move in the height direction of the trunnion 15, the outer peripheral surface 16 of the trunnion 15 and the inner roller 1 are moved.
The frictional force between the roller assembly 17 and the inner peripheral surface 22 of the roller assembly 17
Moment acts around the center of curvature of the curved surface 24 of
In FIG. 3, the force causes the roller assembly 17 to rotate clockwise or counterclockwise. The direction of the rotational force acting on the roller assembly 17 depends on which of the outer race 10 or the tripod member 14 is the driving member, the rotational direction of the outer race 10 and the tripod member 14, and the direction of the trunnion 15 and the inner roller 22. It is determined based on the relative movement direction.

Here, the case where the outer race 10 is a driving member, the tripod member 14 is a driven member, and the outer race 10 and the tripod member 14 rotate counterclockwise in FIG. 3 will be described as an example. in this case,
3, torque is transmitted through a contact portion between the arc-shaped portion 16B located on the right side and the inner peripheral surface 22, and a frictional force acts on the contact portion in the vertical direction in FIG.

First, when the inner roller 18 moves upward relative to the trunnion 15, a counterclockwise moment is generated around the center of curvature of the curved surface 24 shown on the right side of FIG. Works. Therefore,
A rotational force acts in a direction to rotate the roller assembly 17 counterclockwise in FIG. When the inner roller 18 moves downward relative to the trunnion 15, a clockwise moment acts around the center of curvature of the curved surface 24 shown on the right side of FIG. 3 due to the frictional force. Accordingly, a rotational force acts in a direction to rotate the roller assembly 17 clockwise in FIG. In this way, when a rotational force in a predetermined direction acts on the roller assembly 17, the outer roller 2
There is a possibility that the frictional resistance between the groove 0 and the groove 11 is increased, and the forcing force of the third rotation is increased.

However, in this embodiment, since the frictional resistance on the sliding surface between the trunnion 15 and the inner roller 18 is suppressed, the moment acting around the center of curvature of the curved surface 24 of the outer roller 20 is suppressed. Is done. Therefore, the sliding resistance between the groove 11 and the outer roller 20 is suppressed, and the forcing force of the third rotation is suppressed.

Therefore, the outer race 10 is less likely to vibrate in the first axial direction, and the outer race 10 is less likely to vibrate in the axial direction, and the forced force is reduced by the differential 4, the transmission 3, the engine 2, the engine 2, and the like.
Is prevented from being transmitted to the body via the mount part supporting the forcible force, noise due to vibration of components disposed on the transmission path of the forcing force can be prevented, and riding comfort is improved. That is, so-called NV (noise vibration) performance is improved.

Further, heat generation on the sliding surface between the inner roller 18 and the trunnion 15 is suppressed, and heat generation on the sliding surface between the outer roller 20 and the groove 11 is suppressed. The conversion of a part of the torque transmitted by the motor into frictional heat can be suppressed. Therefore, a reduction in the power transmission efficiency of the tripod joint 7 can be suppressed. Further, deterioration and seizure of the grease due to heat generation are suppressed. Also, when the torque of the shaft 8 is transmitted to the outer race 10 via the roller assembly 17, the third-order forcing force is suppressed by the same operation as described above.

In the first embodiment, a plurality of recesses 16C can be formed in the height direction of the trunnion 15. Further, a concave portion (not shown) for holding grease can be formed on the inner peripheral surface 22 of the inner roller 18, and in this case, the same operation and effect as described above can be obtained. (Second embodiment)

FIG. 5 is an enlarged front view showing another example of the structure of the tripod member 14. Outer peripheral surface 16 of trunnion 15
Are formed with two arc-shaped portions 16A and 16B in the circumferential direction. A single groove 26 is formed in the arc-shaped portions 16A and 16B along the circumferential direction.
The groove 26 is configured to hold grease, and its planar shape is an arc. The rest of the configuration of the tripod member 14 is the same as that of the first embodiment, and thus the description thereof is omitted. This groove 26 corresponds to the concave portion of the present invention.

Next, the tripod member 1 shown in FIG.
Part 4 of the manufacturing process will be described. This tripod member 1
As the manufacturing method of No. 4, two types are exemplified. First, the first
In the manufacturing method of (1), a metal material is cold forged with a mold to manufacture a rough material of the tripod member 14. Then
While rotating the tripod 15 of the crude material around the first center line C1, the outer peripheral surface 16
Is cut by a tool or ground by a grindstone to obtain a groove 26.
To form

In the second manufacturing method, a projection for forming the groove 26 is formed in an impression of a mold for cold forging a metal material, and the metal material is forged by the mold. Then, the tripod member 14 is formed, and a groove 26 is formed on the outer peripheral surface 16 of the trunnion 15. The second
In the case of adopting the processing method described above, since the grooves 26 are simultaneously formed in the cold forging step of the metal material, it is not necessary to provide a special processing step for forming the grooves 26, and the manufacturing cost can be suppressed.

In the tripod type joint 7 having the tripod member 14 having the above-described structure, the grease is held by the groove 26, so that the same operation and effect as in the first embodiment can be obtained. Further, since the groove 26 is formed continuously in the circumferential direction of the tripod 15, the sliding surface between the outer peripheral surface 16 of the trunnion 15 and the inner peripheral surface 22 of the inner roller 18 is substantially uniformly distributed in the circumferential direction. Can be lubricated.

The groove 26 of the second embodiment is inserted into the trunnion 1
It is also possible to form a plurality of strips on the outer peripheral surface 16 of 5. Further, it is also possible to form a groove in the inner peripheral surface 22 of the inner roller 18 along the circumferential direction, and even when this configuration is adopted, the same effect as in the first embodiment can be obtained. (Third embodiment)

FIG. 6 is an enlarged front view showing another example of the configuration of the tripod member 14. Outer peripheral surface 16 of trunnion 15
Are formed with two arc-shaped portions 16A and 16B in the circumferential direction. A plurality of spiral grooves 27 are formed in the arc-shaped portions 16A and 16B. This groove 2
Reference numeral 7 denotes a configuration for holding grease. The rest of the configuration of the tripod member 14 is the same as that of the first embodiment, and thus the description thereof is omitted. This groove 27 corresponds to the concave portion of the present invention. The tripod member 14 shown in FIG.
Can be manufactured by the first manufacturing method disclosed in the second embodiment.

In the tripod-type joint 7 having the tripod member 14 having the above structure, the grease is held by the groove 27, so that the same operation and effect as those of the first embodiment can be obtained. Further, since each groove 27 is formed in a spiral shape in the tripod 15, the sliding surface between the outer peripheral surface 16 of the trunnion 15 and the inner peripheral surface 22 of the inner roller 18 can be substantially uniformly lubricated in the circumferential direction. Can be. It is also possible to form a spiral groove on the inner peripheral surface 22 of the inner roller 18, and the same effect as in the first embodiment can be obtained even when this configuration is adopted. (Fourth embodiment)

FIG. 7 is an enlarged front view showing another example of the structure of the tripod member 14. As shown in FIG. Outer peripheral surface 16 of trunnion 15
Are formed with two arc-shaped portions 16A and 16B in the circumferential direction. A plurality of rows of grooves 28 having a predetermined length in the circumferential direction are formed in the arc-shaped portions 16A and 16B in the height direction of the trunnion 15. The groove 28 is configured to hold grease. The planar shape of the groove 28 may be an arc shape or a half-moon shape. The rest of the configuration of the tripod member 14 is the same as that of the first embodiment, and thus the description thereof is omitted. This groove 28
Corresponds to the recess of the present invention.

The tripod member 14 shown in FIG.
May be manufactured by either the first manufacturing method disclosed in the second embodiment or the second manufacturing method. Also in the tripod type joint 7 having the tripod member 14 having the above configuration, the grease is held by the groove 28, so that the same operation and effect as in the first embodiment can be obtained.

The present invention is also applicable to a tripod joint having a configuration in which the outer diameter of the trunnion is set uniformly in the height direction. In the tripod joint of this configuration, the roller assembly and the trunnion are
The roller assembly does not swing with respect to the trunnion, only moving relative to the height of the trunnion. Therefore, the first center line of the trunnion and the second center line of the roller assembly are always kept in a state of coincidence.

[0061]

As described above, according to the present invention, the outer peripheral surface of the shaft portion and the inner peripheral surface of the torque transmitting member come into contact with each other, and the torque is transmitted through each contact portion, and thus the outer member. Transmission of torque is performed between the motor and the inner member. Further, the torque transmitting member moves in the longitudinal direction of the groove with a change in the rotational phase of the outer member and the inner member.

Since the concave portion is formed on at least one of the outer peripheral surface of the shaft portion and the inner peripheral surface of the torque transmitting member, the lubricant is held in the concave portion and the gap between the contact portion between the shaft portion and the torque transmitting member is reduced. Lubrication performance is improved. Therefore, the frictional force generated on the sliding surface between the inner peripheral surface of the torque transmitting member and the outer peripheral surface of the shaft portion is reduced, and heat generation, wear, flaking, adhesion, etc. of the shaft portion or the torque transmitting member are suppressed, and The durability of the universal joint is improved.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a tripod joint according to an embodiment of the present invention.

FIG. 2 is a plan view showing a schematic configuration of a front wheel drive vehicle equipped with a tripod joint according to an embodiment of the present invention.

FIG. 3 is a side end view of the tripod joint according to the embodiment of the present invention.

FIG. 4 is a partial plan view of a tripod joint according to an embodiment of the present invention.

FIG. 5 is a partial front view showing another configuration example of the tripod member used in the tripod joint shown in FIGS. 1 and 3;

FIG. 6 is a partial front view showing another configuration example of the tripod member used in the tripod joint shown in FIGS. 1 and 3;

FIG. 7 is a partial front view showing another example of the configuration of the tripod member used in the tripod type joint shown in FIGS. 1 and 3;

[Explanation of symbols]

8 ... shaft, 10 ... outer race, 11 ... groove,
14: tripod member, 15: trunnion, 16
... outer peripheral surface, 16C ... recess, 17 ... roller assembly,
26, 27, 28 ... groove, A1 ... first axis line, B1 ...
Second axis.

Claims (5)

[Claims] A cylindrical outer member rotatable about a first axis; a cylindrical outer member disposed inside the outer member;
An inner member rotatable about a second axis disposed in a plane including the first axis, formed at predetermined intervals in a circumferential direction on an inner periphery of the outer member, and A plurality of grooves extending in one axial direction, a plurality of shafts formed to protrude from the outer periphery of the inner member, and a plurality of shafts attached to the outer periphery of each shaft, respectively, An annular torque transmitting member movable in a longitudinal direction, wherein the plurality of shaft portions and the torque transmitting members are configured to be relatively movable in a longitudinal direction of each shaft portion, and an inner portion of the outer member. A constant-velocity universal joint in which a lubricant is sealed, wherein at least one of an outer peripheral surface of the shaft portion and an inner peripheral surface of the torque transmitting member is formed with a concave portion for holding the lubricant. Constant velocity universal joint. 2. The constant velocity universal joint according to claim 1, wherein a plurality of the concave portions are arranged at predetermined intervals in a circumferential direction. 3. The constant velocity universal joint according to claim 1, wherein the recess is formed in an arc shape along a circumferential direction. 4. The constant velocity universal joint according to claim 1, wherein the recess is formed in a spiral shape. 5. The device according to claim 1, wherein a plurality of the concave portions are arranged at predetermined intervals in a longitudinal direction of the shaft portion or in an axial direction of the torque transmitting member. Speed universal joint.