JP2022049824A - Constant velocity joint and propeller shaft - Google Patents

Abstract

To provide a constant velocity joint and a propeller shaft, capable of suppressing leakage of grease filled in an outer ring member to the outside of the constant velocity joint while suppressing increase in manufacturing cost of the constant velocity joint.SOLUTION: In a constant velocity joint UJ1 according to the present invention and a propeller shaft PS1 using the constant velocity joint, with respect to a hole part 35 provided in a bottom part 34 of an outer ring member 3, an axial length L, which is an axial dimension, is formed larger than an inner diameter d, which is a radial dimension. This makes it possible to increase internal resistance when grease in a bearing accommodation space 30 passes through the hole part 35 and increase pressure loss in the hole part 35. As a result, it is possible to suppress leakage of grease from the bearing accommodation space 30 to an inner peripheral side space 10 of a cylindrical member 1 through the hole part 35.SELECTED DRAWING: Figure 1

Description

The present invention relates to constant velocity joints and propeller shafts.

As a conventional constant velocity joint and a propeller shaft using the same, for example, those described in Patent Document 1 below are known.

That is, this constant velocity joint is provided via a cage between the outer ring member connected to the tubular member, the inner ring member arranged inside the outer ring member and connected to the rotating shaft, and the outer ring member and the inner ring member. It comprises a plurality of ball members that are rotatably held. A cylindrical boot member that airtightly protects the bearing accommodating space formed inside the outer ring member is mounted between the outer ring member and the rotating shaft, and a constant velocity joint is provided in the bearing accommodating space. It is filled with grease for lubrication. Here, a ventilation hole is formed at the bottom of the outer ring member to communicate the inside and outside of the bearing accommodation space to adjust the internal pressure of the bearing accommodation space, and the ventilation hole is closed in the ventilation hole. A closing mechanism is provided to prevent the grease in the bearing accommodating space from leaking to the tubular member side.

Japanese Unexamined Patent Publication No. 2019-167996

However, in the conventional constant velocity joint, the closing mechanism is complicatedly configured. Therefore, there is a problem that the manufacturing cost of the constant velocity joint and the propeller shaft using the constant velocity joint increases.

Therefore, the present invention has been devised in view of the technical problems of the conventional constant velocity joint and the propeller shaft, and is filled inside the outer ring member while suppressing an increase in the manufacturing cost of the constant velocity joint. It is an object of the present invention to provide a constant velocity joint and a propeller shaft capable of suppressing leakage of grease to the outside of the constant velocity joint.

As one aspect of the present invention, a hole having a larger axial dimension than the radial dimension is formed through the bottom of the outer ring member.

According to the present invention, it is possible to suppress the leakage of grease filled inside the outer ring member to the outside of the constant velocity joint while suppressing an increase in the manufacturing cost of the constant velocity joint.

It is an enlarged sectional view of the main part of the propeller shaft which concerns on 1st Embodiment of this invention. It is an enlarged sectional view of the main part of the propeller shaft which concerns on the modification of 1st Embodiment of this invention. It is an enlarged sectional view of the main part of the propeller shaft which concerns on 2nd Embodiment of this invention. It is an enlarged sectional view of the main part of the propeller shaft which concerns on 3rd Embodiment of this invention.

Hereinafter, embodiments of the constant velocity joint and the propeller shaft according to the present invention will be described in detail with reference to the drawings. In each of the following embodiments, the constant velocity joint and the propeller shaft to which the constant velocity joint and the propeller shaft are applied to the propeller shaft for an automobile will be described as an example.

[First Embodiment]
FIG. 1 shows an enlarged cross-sectional view of a main part in which the vicinity of the constant velocity joint UJ1 of the propeller shaft PS1 according to the first embodiment of the present invention is enlarged and displayed. In the following description, for convenience, the left side of FIG. 1 is referred to as "front" and the right side is referred to as "rear", and the direction along the rotation axis (rotation center) Z of FIG. 1 is "axial direction" and the rotation axis Z. The direction orthogonal to the above will be described as "diametrical direction", and the direction around the rotation axis Z will be described as "circumferential direction".

(Structure of propeller shaft)
As shown in FIG. 1, the propeller shaft PS1 has a tubular member 1 as a first axis connected to a transmission mounted on a vehicle (not shown) and a differential (not shown) mounted on the vehicle. A rotary shaft 2 as a second axis connected to a device (differential) and a constant velocity joint UJ1 connecting the tubular member 1 and the rotary shaft 2 so as to be relatively movable in the axial direction and integrally rotatable. Be prepared.

(Constant velocity joint configuration)
As shown in FIG. 1, the constant velocity joint UJ1 includes a bottomed cylindrical outer ring member 3 whose front end is connected to a tubular member 1, an inner ring member 4 housed on the inner peripheral side of the outer ring member 3, and an inner ring member 4. A plurality of balls 6 rotatably held by an annular cage 5 arranged between the outer ring member 3 and the inner ring member 4 are provided. The bearing accommodating space 30 formed on the inner peripheral side of the outer ring member 3 is filled with grease for lubricating the constant velocity joint UJ1. Further, a substantially cylindrical boot member 7 is provided between the rotary shaft 2 and the outer ring member 3 so as to straddle the rotary shaft 2 and the outer ring member 3. That is, by covering the connecting portion between the tubular member 1 and the rotating shaft 2 with the boot member 7, the inside of the bearing accommodating space 30 is protected in an airtight state, and good lubrication of the constant velocity joint UJ1 is maintained. There is.

The outer ring member 3 is provided on the front end side of the bearing component 31 that accommodates the inner ring member 4 on the inner peripheral side to form a constant velocity joint UJ1 and is provided for connection with the tubular member 1. It has a base 32 and. The bearing component 31 and the connection base 32 are integrally formed, for example, by forging an iron-based material.

The bearing component 31 is formed in a bottomed cylindrical shape with the rear end side open and the front end side closed by the bottom 34. Further, on the inner peripheral side of the bearing component 31, a plurality of outer race grooves 33 extending linearly along the axial direction are formed at equal intervals in the circumferential direction. The outer race groove 33 cooperates with the inner race groove 43 described later to allow the ball 6 to move in the axial direction and regulate the movement of the ball 6 in the circumferential direction.

That is, in the bearing component 31, the ball 6 rolls in the axial direction along the race groove formed between the outer race groove 33 and the inner race groove 43 described later, so that the outer ring member 3 and the inner ring in the axial direction are rolled. Allows relative movement with the member 4. On the other hand, in the bearing component 31, the outer ring member 3 and the inner ring member in the circumferential direction are formed by engaging the ball 6 with the race groove formed between the outer race groove 33 and the inner race groove 43 described later in the circumferential direction. The relative movement of 4, that is, the relative rotation is restricted, and the outer ring member 3 and the inner ring member 4 rotate integrally based on the drive torque input from the outer ring member 3 side.

The connection base portion 32 is provided so as to project from the bottom portion 34 of the bearing component 31 toward the front end side along the axial direction, and is formed in a cylindrical shape in which the front end side opens. Specifically, the connection base portion 32 is formed in a step-reduced diameter shape with respect to the bearing component portion 31, and is set to have substantially the same inner diameter and outer diameter as the cylindrical member 1. The connection base 32 is connected to the tubular member 1 by so-called friction welding. Along with such friction welding, a curl portion 321 that bulges inward and outward in the radial direction is formed in an annular shape along the circumferential direction at the connection portion of the connection base portion 32 to the tubular member 1. .. Further, the curl portion 321 is configured to have an outer diameter smaller than the outer diameter of the bearing constituent portion 31.

The bottom portion 34 of the outer ring member 3 overlaps (overlaps) the rotation axis Z of the propeller shaft PS1 in the radial direction of the relatively thin bottom plate portion 341 forming the general portion, that is, the propeller shaft PS1. At the position of the center of rotation of the above, there is a protruding portion 342 that protrudes toward the tubular member 1 side along the axial direction, and the bottom plate portion 341 and the protruding portion 342 are integrally formed. In other words, the protruding portion 342 is a so-called built-up portion provided at the center position of the bottom plate portion 341 so as to project toward the tubular member 1 side. The protruding portion 342 is set to an axial length L larger than the thickness T of the bottom plate portion 341. Further, the protruding portion 342 is set to have an axial length L larger than that of the connecting base portion 32, and the tip portion of the protruding portion 342 faces the inner peripheral side space 10 of the tubular member 1.

Further, in the present embodiment, the protruding portion 342 is formed in a truncated cone shape whose outer diameter gradually decreases toward the tubular member 1 side. The protrusion 342 is formed, for example, by cutting a radial intermediate portion of the front end side surface (side surface on the tubular member 1 side) of the bottom portion 34 formed to have the same thickness as the protrusion 342 into a donut shape. In this case, since the protruding portion 342 is formed in a truncated cone shape, the base end side (bottom portion 34 side) is formed in a relatively large diameter shape to improve the material yield and the tip side. Can reduce the weight of the propeller shaft PS1 by forming the propeller shaft PS1 with a small diameter.

The form of the protruding portion 342 is not limited to the truncated cone-shaped form exemplified in this embodiment. That is, for the protruding portion 342, any form can be adopted according to the specifications of the propeller shaft PS1 and the function required for the protruding portion 342, such as a columnar shape having a constant outer diameter over the entire axial direction. .. Further, in the present invention, since it is sufficient to secure a long axial length L of the hole portion 35, the protruding direction of the protruding portion 342 is not limited to the direction of the tubular member 1 side exemplified in the present embodiment. However, it is also possible to have a configuration in which the bearing accommodating space 30 is projected to be opposite to the present embodiment.

Further, the bottom portion 34 and the protruding portion 342 integrally provided in the outer ring member 3 have a cross section in which the bearing accommodating space 30 of the outer ring member 3 (bearing component 31) and the inner peripheral side space 10 of the tubular member 1 communicate with each other. A substantially circular hole 35 is formed through the hole 35. That is, the hole 35 releases the internal pressure of the bearing accommodating space 30 increased due to the heat generated by the constant velocity joint UJ1 to the inner peripheral side space 10 of the tubular member 1, thereby accommodating the bearing sealed by the boot member 7. The internal pressure of the space 30 can be adjusted. This makes it possible to suppress the swelling of the boot member 7 and the damage of the boot member 7 due to the swelling.

The hole 35 is provided along the axial direction at a position that overlaps (overlaps) the rotation axis Z of the propeller shaft PS1 in the radial direction, that is, at the rotation center position of the propeller shaft PS1. Further, the hole portion 35 has a constant inner diameter d and has an axial length L larger than the inner diameter d. In other words, the axial length L of the bottom plate portion 341 and the protruding portion 342 on which the hole portion 35 is formed is set to be larger than the inner diameter d of the hole portion 35. Based on the peculiar configuration of the hole portion 35, in the present embodiment, the hole portion 35 is formed only in the relatively thin bottom plate portion 341 by providing the protrusion portion 342 in the axial direction of the hole portion 35. The pressure loss in the hole 35 is increased as compared with the case where the length L is set to be relatively short.

Here, the relationship between the inner diameter d of the hole 35 and the axial length L is based on the following formula, which is a well-known formula for obtaining the pressure loss ΔP in the hole 35.

In the above formula, λ is the coefficient of friction of the hole 35, L is the axial length of the hole 35, d is the inner diameter of the hole 35, ρ is the density of grease, and v is the flow velocity of grease. Therefore, in view of the configuration of the equation, since the inner diameter d and the axial length L are in an inversely proportional relationship, in order to increase the pressure loss ΔP in the hole 35, the inner diameter d is set as small as possible. It is desirable to secure the axial length L as long as possible.

The inner ring member 4 has a cylindrical shape, and a shaft insertion hole 40 into which the rotary shaft 2 is inserted is formed through the inner peripheral side, and the male of the rotary shaft 2 is formed on the inner peripheral side of the shaft insertion hole 40. A female spline portion 41 into which the spline portion 21 fits is formed. In the female spline portion 41, a female spline tooth portion that meshes with the male spline tooth portion of the rotation shaft 2 is formed along the axial direction. Further, on the outer peripheral side of the inner ring member 4, inner race grooves 43, which are axial grooves similar to the outer race groove 33 and extend linearly along the axial direction, are formed at equal intervals in the circumferential direction.

Further, in the female spline portion 41, the sir of the rotary shaft 2 is located at an axial position facing the circlip fitting groove 22 of the rotary shaft 2 with the rotary shaft 2 inserted in the shaft insertion hole 40 of the inner ring member 4. A circlip locking groove 42 that can be locked with the circlip 8 attached to the clip fitting groove 22 is formed in an annular shape along the circumferential direction. That is, when the male spline portion 21 of the rotating shaft 2 is fitted to the female spline portion 41 of the inner ring member 4, the circlip 8 attached to the circlip fitting groove 22 in a contracted state is elastically restored and the circlip. By locking in the locking groove 42, the rotating shaft 2 is prevented from coming off with respect to the inner ring member 4.

The boot member 7 has a cylindrical shape in which an intermediate portion in the axial direction is formed in a folded shape, is formed of a flexible elastic material such as a rubber material, and is inside the front end side attached to the outer ring member 3. An annular core metal 70 is embedded in the ring. The boot member 7 is mounted so as to straddle between the tubular member 1 and the rotary shaft 2, that is, between the rotary shaft 2 and the outer ring member 3, and the intermediate portion is formed in a folded shape. It is configured to expand and contract in the axial direction. Further, in the boot member 7, the front end portion is tightly fixed to the outer peripheral side of the rear end portion of the outer ring member 3 via a well-known boot band B1, and the rear end portion is a well-known boot on the outer peripheral side of the rotation shaft 2. It is tied up and fixed via the band B2.

(Action and effect of this embodiment)
As described above, the conventional propeller shaft is provided with a closing mechanism capable of closing the hole formed through the bottom of the outer ring member, and when the propeller shaft slides in the contraction direction by this closing mechanism. It was possible to suppress the leakage of the grease pushed away by the inner ring member from the hole. However, since the closing mechanism is complicatedly configured, there is a problem that the manufacturing cost of the constant velocity joint and the propeller shaft using the constant velocity joint increases.

On the other hand, the constant velocity joint UJ1 and the propeller shaft PS1 according to the present embodiment can solve the problems of the conventional propeller shaft by achieving the following effects.

The propeller shaft PS1 includes an inner ring member 4 connected to the rotary shaft 2, a plurality of balls 6 arranged outside the inner ring member 4 in the radial direction of the rotary shaft 2 and rotating integrally with the inner ring member 4, and a ball 6. Is formed into a tubular shape that is connected to the tubular member 1 and can accommodate the ball 6 and the inner ring member 4 that are connected to the inner ring member 4 and held in the cage 5, and the inner ring is formed via the ball 6. An outer ring member configured to rotate integrally with the member 4 and transmit the rotational force of the inner ring member 4 to the tubular member 1 so as to be relatively movable with the inner ring member 4 in the axial direction of the rotating shaft 2. An internal space (bearing accommodating space 30) and a tubular member 1 which are formed through the bottom portion 34 so as to face the inner ring member 4 in the direction and are formed between the inner ring member 4 and the bottom portion 34. It is provided with an outer ring member 3 having a hole portion 35 which communicates with the inside of the above and has a larger axial dimension than the radial dimension.

As described above, in the constant velocity joint UJ1 and the propeller shaft PS1 using the constant velocity joint UJ1 according to the present embodiment, the hole portion 35 provided in the bottom portion 34 of the outer ring member 3 is axially oriented with respect to the inner diameter d which is the radial dimension. The axial length L, which is the dimension of the above, is formed to be large. As a result, when the propeller shaft PS1 slides in the direction in which the rotary shaft 2 (inner ring member 4) approaches the bottom portion 34 (contraction direction), the grease pushed away toward the bottom portion 34 by the inner ring member 4 passes through the hole portion 35. It is possible to increase the internal resistance when doing so. As a result, the increase in the internal resistance of the hole 35 increases the pressure loss in the hole 35, and the grease leaks from the bearing accommodating space 30 to the inner peripheral side space 10 of the tubular member 1 through the hole 35. Can be suppressed.

Moreover, in the present embodiment, it is possible to suppress the leakage of grease through the hole 35 only by forming the hole 35 having a length L in the axial direction larger than the inner diameter d in the bottom 34 of the outer ring member 3. There is no possibility that the manufacturing cost of the constant velocity joint UJ1 and the propeller shaft PS1 using the constant velocity joint UJ1 will increase significantly.

Further, in the present embodiment, the bottom portion 34 of the outer ring member 3 has a bottom plate portion 341 and a protruding portion 342 formed so as to protrude from the bottom plate portion 341, and the hole portion 35 includes the bottom plate portion 341 and the protruding portion 342. In the axial direction, the axial length L of the hole portion 35 is larger than the thickness T of the bottom plate portion 341.

As described above, in the present embodiment, the axial length L of the hole portion 35 penetrating the bottom plate portion 341 and the protruding portion 342 is set to be larger than the thickness T of the bottom plate portion 341. Therefore, it is possible to provide a protruding portion 342 only in the central portion of the bottom plate portion 341, which is necessary for securing the axial length L of the hole portion 35, and to reduce the weight of the portion of the bottom plate portion 341 that does not require a large thickness. It will be possible. As a result, it is possible to suppress the leakage of grease due to the hole 35 while suppressing the weight increase of the propeller shaft PS1.

Further, in the present embodiment, the protruding portion 342 projects toward the tubular member 1 side in the axial direction.

As described above, in the present embodiment, the grease leaked from the hole 35 is relatively uniformly applied to the inner peripheral surface of the tubular member 1 by projecting the protruding portion 342 toward the tubular member 1 in the axial direction. It becomes possible to scatter. As a result, the influence of the imbalance of the propeller shaft PS1 caused by the leakage of grease through the hole 35 can be reduced.

Further, in the present embodiment, the hole portion 35 is provided at the center position of the bottom portion 34 in the radial direction.

As described above, in the present embodiment, since the hole 35 is provided at the radial center position of the bottom portion 34, the hole 35 leaks from the hole 35 as compared with the case where the hole 35 is provided at the eccentric position. It is possible to disperse the grease relatively uniformly on the inner peripheral surface of the tubular member 1. As a result, the influence of the imbalance of the propeller shaft PS1 caused by the leakage of grease through the hole 35 can be reduced.

Further, in the present embodiment, the outer ring member 3 has a plurality of outer race grooves 33 on the inner peripheral side facing the ball 6 in the radial direction so as to roll the ball 6 along the axial direction. ..

That is, in a so-called double offset joint, as illustrated in the present embodiment, in a so-called double offset joint in which the ball 6 rolls on the outer race groove 33 so that the inner ring member 4 can smoothly slide in the direction approaching the bottom portion 34. The effect of suppressing the leakage of grease by the portion 35 is more effectively exerted.

(Modification example)
FIG. 2 shows a modified example of the propeller shaft PS1 according to the first embodiment of the present invention, in which a damper 9 for vibration isolation is provided inside the tubular member 1 of the propeller shaft PS1 according to the first embodiment. be. Since the basic configurations other than the changes are the same as those of the first embodiment, the same configurations as those of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. ..

FIG. 2 shows an enlarged cross-sectional view of a main part in which the vicinity of the constant velocity joint UJ1 of the propeller shaft PS1 ′ according to the modified example of the first embodiment of the present invention is enlarged and displayed. In the following description, for convenience, the left side of FIG. 2 will be referred to as “front” and the right side will be referred to as “rear”, and the direction along the rotation axis (rotation center) Z of FIG. 2 will be referred to as “axial direction” and rotation axis Z. The orthogonal direction will be described as "diametrical direction", and the direction around the rotation axis Z will be described as "circumferential direction".

That is, in the propeller shaft PS1'according to the present embodiment, a paper damper 9 formed in a cylindrical shape is arranged inside the tubular member 1 so as to be in close contact with the inner peripheral side of the tubular member 1. There is.

As described above, in this modification, the damper 9 for suppressing vibration is arranged inside the tubular member 1. Then, the grease leaked from the bearing accommodating space 30 of the outer ring member 3 may adhere to the damper 9, and the function of the damper 9 may be deteriorated.

Therefore, as in this modification, in the propeller shaft PS1'in which the damper 9 is arranged inside the tubular member 1, the axial length L is formed larger than the inner diameter d to increase the pressure loss of the hole 35. By doing so, it is possible to prevent grease from leaking from the hole 35 and adhering to the damper 9. As a result, it is possible to suppress the functional deterioration of the damper 9 due to the adhesion of the grease leaked from the bearing accommodating space 30 of the outer ring member 3.

[Second Embodiment]
FIG. 3 shows a second embodiment of the constant velocity joint and the propeller shaft according to the present invention, and is a modification of the configuration of the outer ring member 3 according to the first embodiment. Since the basic configurations other than the changes are the same as those of the first embodiment, the same configurations as those of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. ..

FIG. 3 shows an enlarged cross-sectional view of a main part in which the vicinity of the constant velocity joint UJ2 of the propeller shaft PS2 according to the second embodiment of the present invention is enlarged and displayed. In the following description, for convenience, the left side of FIG. 3 will be referred to as “front” and the right side will be referred to as “rear”, and the direction along the rotation axis (rotation center) Z of FIG. 3 will be referred to as “axial direction” and rotation axis Z. The orthogonal direction will be described as "diametrical direction", and the direction around the rotation axis Z will be described as "circumferential direction".

That is, the propeller shaft PS2 according to the present embodiment is axially connected to the general portion 36 formed between the outer race grooves 33 and 33 adjacent in the circumferential direction on the inner peripheral side of the bearing component 31 of the outer ring member 3. An outer side axial groove 37 extending along the above side is formed.

The outer side axial groove 37 is formed over almost all the axial regions of the general portion 36 formed flat in the axial direction. Further, the outer side axial groove 37 is set to a constant groove depth sufficiently shallow with respect to the outer race groove 33. In other words, the outer side axial groove 37 is set to a shallow groove depth that does not affect the movement regulation of the ball 6 in the circumferential direction by the outer race groove 33.

As described above, the constant velocity joint UJ2 according to the present embodiment and the propeller shaft PS2 using the constant velocity joint UJ2 are located between the outer race grooves 33 on the inner peripheral side of the outer ring member 3 and adjacent to the outer ring member 3 in the circumferential direction. The outer side axial groove 37 extends along the axial direction.

As described above, in the present embodiment, the outer side axial groove 37 extending along the axial direction is provided between the outer race grooves 33 and 33 adjacent to the outer ring member 3. As a result, especially when the propeller shaft PS2 slides in the direction in which the inner ring member 4 approaches the bottom portion 34 (contraction direction), the fluidity of grease in the bearing accommodating space 30 is improved through the outer axial groove 37. It becomes possible. Specifically, the grease located on the bottom 34 side of the bearing accommodating space 30 can be flowed to the opening side (boot member 7 side) of the bearing accommodating space 30 through the outer side axial groove 37. .. As a result, leakage of grease accumulated on the bottom 34 side when sliding in the contraction direction of the propeller shaft PS2 can be more effectively suppressed.

[Third Embodiment]
FIG. 4 shows a third embodiment of the constant velocity joint and the propeller shaft according to the present invention, and is a modification of the configuration of the inner ring member 4 according to the first embodiment. Since the basic configurations other than the changes are the same as those of the first embodiment, the same configurations as those of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. ..

FIG. 4 is an enlarged cross-sectional view of a main part in which the vicinity of the constant velocity joint UJ3 of the propeller shaft PS3 according to the third embodiment of the present invention is enlarged and displayed. , The right side is described as "rear", the direction along the rotation axis (center of rotation) Z in FIG. 4 is the "axial direction", the direction orthogonal to the rotation axis Z is the "radial direction", and the direction around the rotation axis Z is. It will be described as "circumferential direction".

That is, the propeller shaft PS3 according to the present embodiment is the bottom portion of the inner race groove 43 of the inner ring member 4, which is the ball contact surface that comes into contact with the ball 6 when sliding in the axial direction (the deepest position of the inner race groove 43). In the inner side axial groove 44 extending along the axial direction is formed.

The inner side axial groove 44 is provided in all the axial regions along the inner race groove 43, and is set to a constant groove depth sufficiently shallow with respect to the inner race groove 43. In other words, the inner side axial groove 44 is set to a shallow groove depth that does not affect the smooth rolling of the ball 6 in the inner race groove 43.

As described above, in the constant velocity joint UJ3 according to the present embodiment and the propeller shaft PS3 using the constant velocity joint UJ3, the inner ring member 4 is in contact with the ball 6 on the ball contact surface (inner race groove 43) in the axial direction. It has an inner side axial groove 44 extending along the line.

As described above, in the present embodiment, the inner race groove 43, that is, the ball contact surface with which the ball 6 abuts in the inner ring member 4, is provided with the inner side axial groove 44 extending along the axial direction. This improves the fluidity of grease in the bearing accommodating space 30 through the inner side axial groove 44, particularly when the propeller shaft PS3 slides in the direction in which the inner ring member 4 approaches the bottom portion 34 (contraction direction). Is possible. Specifically, the grease located on the bottom 34 side of the bearing accommodating space 30 can be flowed to the opening side (boot member 7 side) of the bearing accommodating space 30 through the inner side axial groove 44. .. As a result, leakage of grease accumulated on the bottom 34 side when sliding in the contraction direction of the propeller shaft PS3 can be more effectively suppressed.

The present invention is not limited to the configurations and embodiments exemplified in each of the above-described embodiments, and can be freely changed according to the specifications and costs of the applicable objects as long as the above-described embodiments of the present invention can be exhibited. can do. Further, the configurations exemplified in the above embodiments are combined with each other (for example, the outer side axial groove 37 exemplified in the second embodiment and the inner side axial groove 44 exemplified in the third embodiment). It is also possible.

Further, in each of the above embodiments, the outer ring member 3 is arranged on the front end side which is the drive side, and the inner ring member 4 is arranged on the driven side which is the rear end side. good. That is, the present invention can be applied to a form in which the outer ring member 3 is arranged on the driven side, which is the rear end side, and the inner ring member 4 is arranged on the drive side, which is the front end side, as in the conventional propeller shaft.

As the constant velocity joint based on each of the above-described embodiments, for example, the one described below can be considered.

That is, in one embodiment of the constant velocity joint, a plurality of inner ring members connected to the rotation shaft and a plurality of inner ring members arranged outside the inner ring member in the radial direction of the rotation shaft and rotating integrally with the inner ring member. The ball, the cage that holds the ball in the inner ring member, and the cylindrical member that is connected to the tubular member and that can accommodate the ball and the inner ring member held in the cage inside are formed into a cylindrical shape. An outer ring member configured to rotate integrally with the inner ring member via the inner ring member and transmit the rotational force of the inner ring member to the tubular member so as to be movable relative to the inner ring member in the axial direction of the rotation axis. A bottom portion arranged so as to face the inner ring member in the axial direction, an internal space formed through the bottom portion and formed between the inner ring member and the bottom portion, and the inside of the tubular member. It is provided with an outer ring member having a hole portion formed so as to have a larger axial dimension than the radial dimension.

In a preferred embodiment of the constant velocity joint, the bottom portion has a bottom plate portion and a protrusion formed from the bottom plate portion, and the hole portion penetrates the bottom plate portion and the protrusion portion. The length of the hole is larger than the thickness of the bottom plate in the axial direction.

In another preferred embodiment, in any of the aspects of the constant velocity joint, the protrusions project towards the tubular member side in the axial direction.

In yet another preferred embodiment, in any of the aspects of the constant velocity joint, the hole is provided at the center of the bottom in the radial direction.

In yet another preferred embodiment, in any of the aspects of the constant velocity joint, the outer ring member is capable of rolling the ball along the axial direction on the inner peripheral side facing the ball in the radial direction. Has multiple outer race grooves to guide.

In yet another preferred embodiment, in any of the constant velocity joint aspects, along the axial direction between the outer race grooves on the inner peripheral side of the outer ring member adjacent to the circumferential direction of the outer ring member. It has an extending outer side axial groove.

In yet another preferred embodiment, in any of the aspects of the constant velocity joint, the inner ring member has an inner side axial groove extending along the axial direction on the ball contact surface in contact with the ball.

Further, as the propeller shaft based on each of the above-described embodiments, for example, the one described below can be considered.

A propeller shaft that transmits the driving force of a vehicle, a rotating shaft arranged on either the driving side or the driven side, and a cylinder arranged on the driving side or the other of the driven side and rotating integrally with the rotating shaft. A shaped member, an inner ring member connected to the rotating shaft, a plurality of balls arranged outside the inner ring member in the radial direction of the rotating shaft and rotating integrally with the inner ring member, and the ball being the inner ring member. It is formed in a tubular shape that is connected to the tubular member and can accommodate the ball and the inner ring member held in the cage inside, and is integrally integrated with the inner ring member via the ball. An outer ring member that rotates and transmits the rotational force of the inner ring member to the tubular member so as to be movable relative to the inner ring member in the axial direction of the rotation axis, and the inner ring member in the axial direction. The radial dimension of the bottom portion arranged so as to face each other, the internal space formed through the bottom portion and formed between the inner ring member and the bottom portion, and the inside of the tubular member. It is provided with an outer ring member having a hole portion having a large axial dimension.

In a preferred embodiment of the propeller shaft, a damper for suppressing vibration is arranged inside the tubular member.

1 ... Cylindrical member, 2 ... Rotating shaft, 3 ... Outer ring member, 30 ... Bearing accommodation space (internal space), 33 ... Outer race groove, 34 ... Bottom, 341 ... Bottom plate, 342 ... Projection, 35 ... Hole, 4 ... Inner ring member, 5 ... Cage, 6 ... Ball, 7 ... Boot member, PS1 to PS3 ... Propeller shaft, Z ... Rotation axis,

Claims (9)

The inner ring member connected to the rotating shaft and
A plurality of balls arranged outside the inner ring member in the radial direction of the rotation axis and rotating integrally with the inner ring member.
A cage that holds the ball in the inner ring member,
The ball connected to the tubular member and held in the cage is formed in a tubular shape capable of accommodating the inner ring member inside, and the inner ring member rotates integrally with the inner ring member via the ball to form the inner ring member. An outer ring member configured to be movable relative to the inner ring member in the axial direction of the rotation axis while transmitting a rotational force to the cylindrical member.
A bottom portion arranged so as to face the inner ring member in the axial direction,
The internal space formed through the bottom portion and formed between the inner ring member and the bottom portion communicates with the inside of the tubular member, and the axial dimension is formed larger than the radial dimension. With the hole that was made,
With an outer ring member,
A constant velocity joint characterized by being equipped with. In the constant velocity joint according to claim 1,
The bottom portion has a bottom plate portion and a protrusion formed from the bottom plate portion.
The hole portion is provided so as to penetrate the bottom plate portion and the protruding portion.
A constant velocity joint characterized in that the length of the hole portion in the axial direction is larger than the thickness of the bottom plate portion. In the constant velocity joint according to claim 2.
The projecting portion is a constant velocity joint characterized in that it projects toward the tubular member side in the axial direction. In the constant velocity joint according to claim 1,
The hole is a constant velocity joint provided at the center of the bottom in the radial direction. In the constant velocity joint according to claim 1,
The outer ring member is a constant velocity joint having a plurality of outer race grooves on the inner peripheral side facing the ball in the radial direction so as to roll the ball along the axial direction. In the constant velocity joint according to claim 5.
A constant velocity joint characterized by having an outer side axial groove extending along the axial direction between the outer race grooves adjacent to the outer ring member in the circumferential direction among the inner peripheral sides of the outer ring member. In the constant velocity joint according to claim 1,
The inner ring member is a constant velocity joint having an inner side axial groove extending along the axial direction on a ball contact surface that comes into contact with the ball. A propeller shaft that transmits the driving force of the vehicle.
A rotating shaft located on either the drive side or the driven side,
A cylindrical member arranged on the other side of the driving side or the driven side and rotating integrally with the rotating shaft.
The inner ring member connected to the rotating shaft and
A plurality of balls arranged outside the inner ring member in the radial direction of the rotation axis and rotating integrally with the inner ring member.
A cage that holds the ball in the inner ring member,
The ball connected to the tubular member and held in the cage is formed in a tubular shape capable of accommodating the inner ring member inside, and the inner ring member rotates integrally with the inner ring member via the ball. An outer ring member configured to be movable relative to the inner ring member in the axial direction of the rotation axis while transmitting the rotational force of the above to the cylindrical member.
A bottom portion arranged so as to face the inner ring member in the axial direction,
The internal space formed through the bottom portion and formed between the inner ring member and the bottom portion communicates with the inside of the tubular member, and the axial dimension is formed larger than the radial dimension. With the hole that was made,
With an outer ring member,
Propeller shaft characterized by being equipped with. In the propeller shaft according to claim 8,
A propeller shaft characterized in that a damper for suppressing vibration is arranged inside the tubular member.

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