WO2020066997A1 - Stationary constant velocity universal joint - Google Patents

Abstract

This stationary constant velocity universal joint is provided with a cup-shaped outer joint member (11), an inner joint member (12) which is housed in the outer joint member (11), and balls (13) which are arranged between the track groove (16) of the outer joint member (11) and the track groove (18) of the inner joint member (12) and transmitting rotational torque. A protrusion (23) capable of interfering with the balls (13) is integrally formed by plastic deformation at the open end of the track groove (16) of the outer joint member (11).

Description

Fixed type constant velocity universal joint

The present invention relates to a fixed type constant velocity universal joint used for a power transmission system of an automobile or various industrial machines, and particularly incorporated in a drive shaft for an automobile rear or a propeller shaft for an automobile.

等 There are two types of constant velocity universal joints used as means for transmitting a rotational force from an automobile engine to wheels at a constant speed: a fixed type constant velocity universal joint and a sliding type constant velocity universal joint. Both of the constant velocity universal joints have a structure in which two shafts on the driving side and the driven side are connected to each other and can transmit rotational torque at a constant speed even when the two shafts take an operating angle.

ド ラ イ ブ A drive shaft that transmits power from the engine of an automobile to the wheels must cope with angular displacement and axial displacement due to changes in the relative positional relationship between the engine and the wheels. Therefore, the drive shaft generally has a sliding constant velocity universal joint that allows both axial displacement and angular displacement on the engine side (inboard side), and a fixed constant velocity universal joint that allows only angular displacement. Is mounted on the wheel side (outboard side), and the constant velocity universal joints of both are connected by a shaft.

The fixed type constant velocity universal joint is mainly applied to the wheel side of a front drive shaft of an automobile in that it cannot tolerate axial displacement but can tolerate a large operating angle (maximum operating angle of 45 ° or more).

On the other hand, the fixed type constant velocity universal joint is sometimes applied to the wheel side of a drive shaft for an automobile rear or a propeller shaft for an automobile. In this case, the maximum operating angle does not need to be 45 ° or more as in the case of the front of the vehicle, and the maximum operating angle is 30 ° or less for the rear of the vehicle and 10 ° or less for the propeller shaft.

Since the maximum operating angle of a drive shaft for an automobile rear is as small as 30 ° or less, the track groove is made smaller than that of the outer joint member used for the drive shaft for the automobile front in order to reduce the weight and cost of the constant velocity universal joint. The outer joint member is shortened to reduce the axial dimension.

Here, when assembling the constant velocity universal joint, the ball is incorporated in an angle greater than the maximum operating angle. After the shaft is assembled, the shaft and the outer joint member interfere with each other at an angle lower than the ball installation angle, so that the ball is prevented from falling off the track groove of the outer joint member.

However, in a constant velocity universal joint used for an automobile rear drive shaft having an outer joint member having a small axial dimension, if the operating angle is increased, the angle at which the ball falls off before the shaft interferes with the outer joint member is increased. And the ball comes off the track groove of the outer joint member and falls off.

In view of this, various constant velocity universal joints have been proposed which are provided with means for preventing the ball from coming off from the track groove of the outer joint member and falling off when handling the constant velocity universal joint (for example, Patent Documents 1 to 4). 3).

JP-A-3-113124 JP 2001-280359 A JP 2008-215404 A

By the way, the constant velocity universal joints of Patent Literatures 1 to 3 provided with means for preventing the ball from coming off from the track groove of the outer joint member and falling off when handling the constant velocity universal joint have the following structure. And have challenges.

The constant velocity universal joint disclosed in Patent Document 1 has a stopper structure in which an end portion of a shaft fitted to an inner joint member is extended, and the extended portion of the shaft can be brought into contact with a bottom portion of the outer joint member. Is provided.

In this constant velocity universal joint, when the shaft has an operating angle larger than the maximum operating angle with respect to the outer joint member, the extending portion of the shaft interferes with the bottom of the outer joint member, so that the ball is formed on the outer joint member. It is prevented from falling off the track groove and falling off.

However, in the case of the constant velocity universal joint disclosed in Patent Document 1, the end of the shaft becomes unnecessarily long, and the weight of the shaft increases accordingly. This increase in weight of the shaft makes it difficult to reduce the weight of the constant velocity universal joint.

The constant velocity universal joint disclosed in Patent Literature 2 has a projection provided at a portion near an opening of an outer joint member of a shaft fitted to an inner joint member, and the projection can be brought into contact with an open end of the outer joint member. A stopper structure is provided.

In this constant velocity universal joint, when the shaft has an operating angle larger than the maximum operating angle with respect to the outer joint member, the projection of the shaft interferes with the open end of the outer joint member, so that the ball is formed on the outer joint member. It is prevented from falling off the track groove and falling off.

However, in the case of the constant velocity universal joint disclosed in Patent Literature 2, it is necessary to increase the diameter of the material before cutting the shaft in order to form a projection on the shaft. As described above, it is necessary to cut the shaft, and since the material of the shaft needs to be large in diameter, it is difficult to reduce the cost of the constant velocity universal joint in terms of cutting and material costs. Become.

等 The constant velocity universal joint disclosed in Patent Document 3 has a stopper structure in which a locking member is attached to an end of a retainer, and the locking member can contact an end of the inner joint member.

In this constant velocity universal joint, when the shaft takes an operating angle larger than the maximum operating angle with respect to the outer joint member, the locking member of the retainer interferes with the end of the inner joint member, so that the ball is connected to the outer joint member. It is prevented from falling off the track groove of the member.

However, in the case of the constant velocity universal joint disclosed in Patent Document 3, a separate locking member from the components of the constant velocity universal joint is required. As a result, the number of parts of the constant velocity universal joint increases, which leads to an increase in the cost of the constant velocity universal joint.

In view of the above, the present invention has been proposed in view of the above-described problems. An object of the present invention is to prevent balls from falling off from an outer joint member when handling a constant velocity universal joint, and to reduce the weight and cost. It is an object of the present invention to provide a fixed type constant velocity universal joint which can easily reduce the size.

The fixed type constant velocity universal joint according to the present invention has a cup-shaped outer joint member, an inner joint member housed in the outer joint member, and a track groove between the outer joint member and the inner joint member. And a ball for transmitting the rotational torque therethrough.

As a technical means for achieving the above-mentioned object, the present invention relates to a caulking structure for stopping a ball, that is, a projection capable of interfering with a ball is integrated with an open end of a track groove of an outer joint member or an inner joint member. It is characterized in that it is formed in a uniform manner.

According to the present invention, the protrusion capable of interfering with the ball is formed integrally with the open end of the track groove. Interfere with projections. Thereby, it is possible to prevent the ball from being detached from the outer joint member and falling off.

突起 Thus, the projection exerts a stopper function to interfere with the ball when handling the constant velocity universal joint. On the other hand, at an operating angle smaller than the maximum operating angle when the joint is used, the projection does not interfere with the ball. As a result, it is possible to take the operating angle required by the constant velocity universal joint assembled to the vehicle body or the like.

As described above, since the protrusion capable of interfering with the ball is formed integrally with the outer joint member or the inner joint member, it is not necessary to extend the end of the shaft as in the related art. The weight can be reduced. Further, since it is not necessary to provide a projection on the shaft, the material diameter of the shaft can be reduced, and the cost of the constant velocity universal joint can be reduced. Further, since a member other than the component parts of the constant velocity universal joint is not required, the number of parts can be reduced.

突起 The projection in the present invention preferably has a structure formed by plastically deforming the open end of the track groove of the outer joint member or the inner joint member.

れ ば By adopting such a structure, it is possible to easily manufacture the projection integrally with the outer joint member or the inner joint member.

The protrusion according to the present invention radially inflates the groove bottom corresponding portion of the open end of the track groove of the outer joint member, or the groove bottom corresponding portion of the open end of the track groove of the inner joint member in the radial direction. It is desirable to have a structure that can bulge outward and interfere with the ball.

By adopting such a structure, the ball that rolls in the track groove is locked by the projection, so that the stopper can easily exhibit the stopper function of interfering with the ball.

According to the present invention, at the time of handling a constant velocity universal joint, at a smaller angle than the angle at which the ball is incorporated, the ball interferes with the projection at the end of the track groove opening, so that the ball comes off from the outer joint member and falls off. Can be prevented beforehand.

ス ト ッ パ Thus, the weight of the constant velocity universal joint can be reduced, the cost can be reduced, and the number of parts can be reduced by the stopper structure formed by the interference between the ball rolling in the track groove and the projection at the open end of the track groove.

FIG. 1 is a cross-sectional view illustrating an entire configuration of a fixed type constant velocity universal joint having an operation angle of 0 ° in an embodiment of the present invention. FIG. 2 is a sectional view taken along the line PP of FIG. 1. FIG. 2 is an enlarged sectional view of a main part of FIG. 1. FIG. 4 is an arrow view of the fixed type constant velocity universal joint of FIG. 3 when viewed from an X direction. FIG. 2 is a cross-sectional view showing a state in which the fixed type constant velocity universal joint of FIG. 1 takes an operating angle and is angle-restricted by a stopper structure. FIG. 6 is an enlarged sectional view of a main part of FIG. 5. It is sectional drawing which shows the whole structure of the fixed type constant velocity universal joint in the state of 0 degree of operation angles in other embodiment of this invention. FIG. 8 is an enlarged sectional view of a main part of FIG. 7. FIG. 9 is a view of the fixed type constant velocity universal joint of FIG. 8 as viewed from an X direction. FIG. 8 is a cross-sectional view showing a state in which the fixed type constant velocity universal joint shown in FIG. 7 takes an operating angle and is restricted in angle by a stopper structure. It is a principal part expanded sectional view of FIG.

An embodiment of the fixed type constant velocity universal joint according to the present invention will be described below in detail with reference to the drawings.

ド ラ イ ブ A drive shaft that transmits power from the engine of an automobile to the wheels must cope with angular displacement and axial displacement due to changes in the relative positional relationship between the engine and the wheels.

Therefore, the drive shaft has a fixed constant velocity universal joint that allows only angular displacement on the wheel side (outboard side) and a sliding constant velocity universal joint that allows both axial displacement and angular displacement on the engine side ( On the inboard side) and a structure in which both constant velocity universal joints are connected by a shaft.

In the following embodiment, for example, a Zeppa type constant velocity universal joint (BJ), which is one of fixed type constant velocity universal joints incorporated in a drive shaft for an automobile rear, is exemplified. It is also applicable to undercut free type constant velocity universal joints (UJ).

As shown in FIGS. 1 and 2, a Zeppa type constant velocity universal joint (hereinafter, simply referred to as a constant velocity universal joint) of this embodiment includes a cup-shaped outer joint member 11, an inner joint member 12, and a plurality of inner joint members. A shaft 15 including a ball 13 and a cage 14 is connected to a shaft 15 extending from the inner joint member 12 and protruding from an opening of the outer joint member 11.

In the outer joint member 11, arcuate track grooves 16 extending in the axial direction are formed at a plurality of positions in the circumferential direction of the spherical inner peripheral surface 17 at equal intervals. In the inner joint member 12, arc-shaped track grooves 18 are formed at a plurality of positions in the circumferential direction of the spherical outer peripheral surface 19 at equal intervals in a pair with the track grooves 16 of the outer joint member 11.

The ball 13 is interposed between the track groove 16 of the outer joint member 11 and the track groove 18 of the inner joint member 12 to transmit the rotational torque. The number of the balls 13 may be 6, 8, or other, and the number is arbitrary. The cage 14 is disposed between the inner peripheral surface 17 of the outer joint member 11 and the outer peripheral surface 19 of the inner joint member 12 to hold the ball 13 in the pocket 20.

The shaft 15 is press-fitted into the shaft hole 21 of the inner joint member 12 and connected so that torque can be transmitted by spline fitting. The shaft 15 is retained by the retaining ring 22 with respect to the inner joint member 12.

In the constant velocity universal joint having the above configuration, when an operating angle is given between the outer joint member 11 and the inner joint member 12 by the shaft 15, the ball 13 held by the cage 14 is always in any operating angle. , Is maintained in the bisecting plane of its operating angle.

Thereby, constant velocity between the outer joint member 11 and the inner joint member 12 is ensured. Rotational torque is transmitted between the outer joint member 11 and the inner joint member 12 via the ball 13 in a state where constant velocity is secured.

Here, the constant velocity universal joint used in the front drive shaft of an automobile can have an operating angle up to 47 °, while the constant velocity universal joint used in the rear drive shaft of an automobile has a maximum operating angle of 30 °. Less than the following.

The constant velocity universal joint for the rear does not require a track groove having an operating angle of 30 ° to 47 °. Therefore, the track grooves 16 and 18 of the outer joint member 11 and the inner joint member 12 are made shorter than those for the front joint. The axial dimension of the member 11 and the inner joint member 12 can be reduced.

(4) When the axial dimension of the outer joint member 11 and the inner joint member 12 is reduced, the angle at which the ball 13 is incorporated can be reduced, and the pocket length of the cage 14 can be shortened, so that the load capacity of the cage 14 increases.

{Circle around (7)} When the maximum operating angle used is small, the fluctuation of the load value acting on each ball 13 is small, and the peak load is reduced. Therefore, the ball PCD can be reduced by the increased torque load capacity of the constant velocity universal joint, and compactness in the radial direction can be achieved.

If the number of balls 13 is eight (see FIG. 2), the load applied to one ball is smaller than that of six balls, so that the ball diameter can be reduced. The track grooves 16, 18 of the joint member 12 can be made shallow.

As described above, in the constant velocity universal joint used for the rear drive shaft, the axial dimension of the inner joint member 12 is reduced, and the number of the balls 13 is set to eight, so that both ends of the inner joint member 12 are formed. Since the thickness of the track groove bottom can be increased, the PCD of the spline can be increased, and the torque load capacity of the spline fitting portion can be increased.

On the other hand, at the time of assembling the constant velocity universal joint used for the rear drive shaft, the ball 13 is installed at a position where the pocket 20 of the cage 14 can be seen from the outer joint member 11 at an angle larger than the maximum operating angle. Done.

Here, after assembling the ball 13, the internal components including the inner joint member 12, the ball 13, and the cage 14 are in a free state during handling such as transporting the constant velocity universal joint or assembling to the vehicle body. In this state, even if the maximum operating angle when the joint is used is 30 ° or less, the constant velocity universal joint may exceed the maximum operating angle due to the weight of the internal components.

As described above, when the constant velocity universal joint is handled, a means for preventing the ball 13 from falling out of the track groove 16 of the outer joint member 11 when the constant velocity universal joint exceeds the maximum operating angle. In this embodiment, the following stopper structure is employed.

As shown in FIGS. 3 and 4, the rear constant velocity universal joint of this embodiment has a caulking structure for stopping the ball 13, and a projection 23 capable of interfering with the ball 13 is formed in the track groove 16 of the outer joint member 11. It has a structure integrally formed at the end. The protrusion 23 is formed by plastically deforming the open end of the track groove 16 of the outer joint member 11.

That is, the portion corresponding to the groove bottom at the open end of the track groove 16 of the outer joint member 11 is crushed. Due to this crushing, a depression 24 is formed at a position corresponding to the groove bottom, and the excess thickness of the depression 24 bulges inward in the radial direction. Due to such plastic deformation, the projection 23 is formed such that the groove bottom corresponding portion at the open end of the track groove 16 bulges inward in the radial direction.

The protrusion 23 may be formed only in a part of the opening end of the track groove 16 corresponding to the groove bottom as in this embodiment, but may be formed over the entire circumference of the opening end of the track groove 16. Good. Further, the projections 23 do not need to be formed in all the track grooves 16 of the outer joint member 11, and may be formed, for example, every other track groove 16 of the outer joint member 11.

In the constant velocity universal joint having the above-described stopper structure, at the time of handling such as transporting or assembling to a vehicle body, as shown in FIGS. 5 and 6, at an angle larger than the maximum operating angle when using the joint, and The ball 13 that rolls in the track groove 16 of the outer joint member 11 at an angle smaller than the mounting angle of the ball 13 interferes with the protrusion 23 at the open end of the track groove 16.

突起 Thus, the projection 23 exerts a stopper function of restricting the shaft 15 to an angle smaller than the angle at which the ball 13 falls due to interference with the ball 13. As a result, it is possible to prevent the ball 13 from falling off the track groove 16 of the outer joint member 11 when handling the constant velocity universal joint.

Further, since the angle at which the projection 23 interferes with the ball 13 is larger than the maximum operating angle when the joint is used, the constant velocity universal joint mounted on the vehicle body is required after handling the constant velocity universal joint. An operating angle can be taken.

As described above, since the protrusion 23 that can interfere with the ball 13 is formed integrally with the outer joint member 11, there is no need to extend the end of the shaft as in the related art. Can be achieved. Further, since it is not necessary to provide a projection on the shaft, the material diameter of the shaft can be reduced, and the cost of the constant velocity universal joint can be reduced. Further, since a member other than the component parts of the constant velocity universal joint is not required, the number of parts can be reduced.

In the above embodiment, the case where the projections 23 are provided on the outer joint member 11 as the crimping structure for stopping the ball 13 is exemplified. However, as another crimping structure, as shown in FIG. The structure provided with the projection 25 may be used.

The rear constant velocity universal joint of this embodiment has a structure in which a projection 25 capable of interfering with the ball 13 is formed integrally with the open end of the track groove 18 of the inner joint member 12, as shown in FIGS. Is provided. The protrusion 25 is formed by plastically deforming the open end of the track groove 18 of the inner joint member 12.

That is, the portion corresponding to the groove bottom at the open end of the track groove 18 of the inner joint member 12 is crushed. Due to this crushing, a depression 26 is formed at a portion corresponding to the groove bottom, and the excess thickness of the depression 26 bulges outward in the radial direction. Due to such plastic deformation, the projection 25 is formed such that a portion corresponding to the groove bottom at the opening end of the track groove 18 swells radially outward.

The protrusion 25 may be formed only on a part of the opening end of the track groove 18 corresponding to the groove bottom as in this embodiment, but is formed over the entire circumference of the opening end of the track groove 18. Is also good. Further, the projections 25 need not be formed in all the track grooves 18 of the inner joint member 12, and may be formed, for example, every other track groove 18 of the inner joint member 12.

In the constant velocity universal joint having the above-described stopper structure, at the time of handling such as transporting or assembling to a vehicle body, as shown in FIGS. 10 and 11, at an angle larger than the maximum operating angle when using the joint, and The ball 13 that rolls in the track groove 18 of the inner joint member 12 at an angle smaller than the mounting angle of the ball 13 interferes with the projection 25 at the open end of the track groove 18.

As shown in FIG. 10, for example, when the shaft 15 takes an operating angle downward in the figure, the protrusion 25 is smaller than the angle at which the ball 13 at the uppermost position falls due to interference with the ball 13 at the lowermost position. It exerts a stopper function of restricting the shaft 15 at an angle.

Due to this stopper function, when handling the constant velocity universal joint, the uppermost ball 13 (see FIG. 10) located in the opposite direction to the lowermost ball 13 that interferes with the projection 25 by 180 ° is the track groove 16 of the outer joint member 11. It can be prevented from falling off and falling off.

Further, since the angle at which the projection 25 interferes with the ball 13 is larger than the maximum operating angle when the joint is used, the constant velocity universal joint mounted on the vehicle body is required after handling the constant velocity universal joint. An operating angle can be taken.

As described above, since the projection 25 capable of interfering with the ball 13 is formed integrally with the inner joint member 12, it is not necessary to extend the end of the shaft unlike the conventional art. Can be achieved. Further, since it is not necessary to provide a projection on the shaft, the material diameter of the shaft can be reduced, and the cost of the constant velocity universal joint can be reduced. Further, since a member other than the component parts of the constant velocity universal joint is not required, the number of parts can be reduced.

The present invention is not limited to the above-described embodiment at all, and it is needless to say that the present invention can be embodied in various forms without departing from the gist of the present invention. And further includes the equivalent meanings described in the claims and all changes within the ranges.

Claims (7)

A cup-shaped outer joint member, an inner joint member housed in the outer joint member, and a ball interposed between a track groove of the outer joint member and a track groove of the inner joint member to transmit rotational torque; A fixed type constant velocity universal joint having
A fixed type constant velocity universal joint, wherein a caulking structure for stopping the ball is provided in the track groove. 2. The fixed type constant velocity universal joint according to claim 1, wherein the caulking structure has a projection capable of interfering with the ball integrally formed at an open end of the track groove of the outer joint member. The fixed type constant velocity universal joint according to claim 2, wherein the protrusion is formed by plastically deforming an open end of the track groove of the outer joint member. 4. The fixed constant velocity freely according to claim 2, wherein the protrusion is capable of interfering with the ball by bulging a portion corresponding to a groove bottom of an opening end of the track groove of the outer joint member radially inward. 5. Fittings. The fixed type constant velocity universal joint according to claim 1, wherein the caulking structure has a protrusion capable of interfering with the ball formed integrally with an opening end of the track groove of the inner joint member. The fixed type constant velocity universal joint according to claim 5, wherein the protrusion is formed by plastically deforming an open end of the track groove of the inner joint member. 7. The fixed type constant velocity freely according to claim 5, wherein the protrusion is capable of interfering with the ball by bulging a portion corresponding to a groove bottom of an opening end of the track groove of the inner joint member radially outward. Fittings.

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