JP3300663B2 - Barfield constant velocity universal joint - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Barfield constant velocity universal joint used as a component of a vehicle power transmission device.

[0002]

2. Description of the Related Art Generally, constant velocity universal joints arranged on a power transmission path of a vehicle include a barfield type, a tripod type, a double offset type, a cross groove type and a double cardan type. Among them, a barfield type constant velocity universal joint frequently used on the wheel side of a front drive shaft of a vehicle particularly includes an inner race and an outer race arranged outside the inner race. A plurality of inner grooves are formed on the outer peripheral surface of the inner race, and a plurality of outer grooves are formed on the inner peripheral surface of the outer race. And one inner groove and one
One set of the outer grooves is used to hold a ball for each set.

[0003] Further, a bisecting plane is set, which bisects the angle between the first axis of the inner race and the second axis of the outer race. The center of curvature of the inner groove in the plane including the first axis and the center of curvature of the outer groove in the plane including the second axis are offset on both sides of the bisector. Furthermore, an annular retainer is arranged between the inner race and the outer race. Each ball is held by the holder.

When the drive shaft is mounted on the vehicle, the inner race is connected to the shaft on the differential side, and the outer race is connected to the wheels. Here, the height of the connecting portion of the shaft on the differential side is different from the height of the connecting portion of the outer race on the wheel side. Therefore, the first axis of the inner race intersects with the second axis of the outer race, and a predetermined joint angle is set.

According to the barfield type constant velocity universal joint having the above structure, the torque output from the differential is:
The power is transmitted to the wheels via the inner race, the ball, and the outer race, and the vehicle runs by the driving force of the wheels. Here, during transmission of the torque by the Barfield constant velocity universal joint, each ball moves in a direction orthogonal to the bisector while being held by the retainer, and the center of each ball is divided into the bisector. The inner race and the outer race are held at the same speed to maintain constant rotation.

However, in the above-mentioned Barfield type constant velocity universal joint, the center of curvature of the plurality of inner grooves is
The centers of curvature of the plurality of outer grooves are offset on both sides of the bisector. Therefore, at the time of transmitting the torque, two loads toward the center of the ball are generated at the contact points between the inner groove and the outer groove and the ball.

[0007] Then, the ball is pressed in a direction orthogonal to the bisector by the resultant force of the two loads, and the pressing force presses the retainer against the outer peripheral surface of the inner race and the inner peripheral surface of the outer race. Therefore, the contact between the retainer and the inner race and the outer race, the contact between the retainer and the ball, or the contact between the ball and the inner groove and the outer groove, heat generated by friction, and fatigue due to repeated load, Peeling occurs. As a result, various problems such as a decrease in the durability of the Barfield constant velocity universal joint, a decrease in the torque transmission function, and an increase in vibration and muffled noise have occurred.

On the other hand, an example of the invention capable of suppressing the resultant force acting on the ball is described in Japanese Patent Application Laid-Open No. Hei 7-91458. This publication describes that an angle between a line segment connecting a contact point between the ball and the inner groove and the outer groove to the center of the ball and a bisecting surface, that is, a pinching angle is set to be small. When this configuration is adopted, the resultant force in the direction perpendicular to the bisector is reduced, and friction and repetition at the contact point between the retainer and the inner race and the outer race or between the contact point between the retainer and the ball are reduced. The load is reduced.

In the invention described in the above publication, the center of curvature corresponding to the axially proximal portion of the inner groove and the outer groove, which comes into contact with the ball when the ball enters the outer race, is provided. , Are set at positions different from the centers of curvature in other portions. Specifically, the included angle corresponding to the base end portion is set to be larger than the included angle corresponding to the other portions. For this reason, when the ball enters the inside of the outer race due to the constant speed rotation of the inner race and the outer race, the ball lock is suppressed, and the heat generation of the contact point is further suppressed.

[0010]

However, according to the invention described in the above publication, the resultant force in the direction perpendicular to the bisector can be suppressed. It is not possible to reduce the load acting on this contact point. For this reason, due to the load generated at the contact point between each ball and the inner groove and the outer groove,
For ball or inner race or outer race,
The problem of generation of heat, fatigue, or peeling could not be solved. Further, the problem that the vibration and the muffled sound are increased during the transmission of the torque cannot be solved.

The present invention has been made in view of the above circumstances, and provides a Barfield type constant velocity universal joint capable of minimizing a load generated at a contact point between a ball and an inner groove or an outer groove. It is intended to be. Another object of the present invention is to provide a barfield type constant velocity universal joint capable of maintaining the same torque function and durability even when the inner race and the outer race rotate in either forward or reverse directions. Is to provide.

[0012]

In order to achieve the above object, the invention according to claim 1 comprises an inner race having a plurality of inner grooves formed on an outer peripheral surface thereof, the inner race being disposed outside the inner race, and An outer race in which a plurality of outer grooves are formed on an inner peripheral surface; a plurality of balls arranged in each set with the one inner groove and the one outer groove as one set; an inner race and the outer race; An annular retainer arranged between the race and the center of the ball on a bisecting plane that bisects the angle between the first axis of the inner race and the second axis of the outer race; Wherein the center of curvature of the inner groove in a plane including the first axis and the center of curvature of the outer groove in a plane including the second axis are on both sides of the bisecting surface. In Barfield type constant velocity universal joint being offset, at least a portion of said plurality of inner grooves, wherein are formed in a spiral direction on the outer circumference of the inner race, at least a portion of said plurality of outer grooves,
At least one set of the adjacent inner grooves is formed in the inner periphery of the outer race in a spiral direction, and at least one set of the adjacent inner grooves passes through the middle between the inner grooves and is based on a plane including the first axis. Is configured as plane symmetric,
At least one set of adjacent outer grooves passes through the middle between the outer grooves and is configured to be plane-symmetric with respect to a plane including the second axis.

According to the first aspect of the invention, the transmission of torque by the ball is performed between the inner race and the outer race. Further, the center of each ball is held on a bisecting plane, and the inner race and the outer race rotate at a constant speed.

On the other hand, since the centers of curvature of the inner groove and the outer groove are offset on both sides of the bisector,
The number of contact points between each ball and the inner and outer grooves is 3
Displaced dimensionally. The maximum value of the load generated at the contact point between each ball and the inner groove and the outer groove is determined by the balance of the product (moment) between the load on each ball and the length of the orthogonal line. Here, the orthogonal line means a line segment set at a right angle to the line of action of the load from the intersection of the first axis and the second axis, that is, the arm of the moment.

According to the first aspect of the present invention, at least a part of the plurality of inner grooves is formed in a spiral direction on the outer periphery of the inner race, and at least a part of the plurality of outer grooves is formed on the inner periphery of the outer race. Since the ball is formed in the spiral direction, the length of the orthogonal line can be set as long as possible for the ball having the phase with the maximum load.
That is, since the moment is constant, the maximum load is suppressed by making the orthogonal line as long as possible.

According to the first aspect of the present invention, at least one pair of adjacent inner grooves passes through the middle between the inner grooves and is plane-symmetric with respect to a plane including the first axis. Is configured. Further, at least one set of adjacent outer grooves passes through the middle between the outer grooves and is configured to be plane-symmetric with respect to a plane including the second axis. Therefore, even when the inner race and the outer race rotate in either the forward or reverse direction, the maximum value of the load generated at the contact point between each ball, the inner groove and the outer groove,
It becomes possible to control almost the same.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, an inclination direction of a central portion in a length direction of the plurality of inner grooves with respect to the first axis, and the plurality of inners with respect to the first axis. The inclination directions of both ends in the longitudinal direction of the groove are different from each other, and the inclination directions of the central portions in the longitudinal direction of the plurality of outer grooves with respect to the second axis, and the inclination directions of the plurality of outer grooves with respect to the second axis. It is characterized in that the inclination directions of both ends in the length direction are different.

According to the second aspect of the present invention, in addition to the same operation as the first aspect, the inclination direction of the center portion in the length direction of the inner groove and the outer groove, and the inclination direction of the both end portions in the length direction are obtained. Are different. For this reason, when the ball held by the inner groove and the outer groove moves to both ends in the length direction of the inner groove and the outer groove, the length of the orthogonal line, that is, the arm of the moment becomes longer. . For this reason, it is possible to make the maximum value of the load acting on the contact point between the inner groove and the outer groove and the ball more uniform.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a barfield type constant velocity universal joint according to the present invention will be described in detail with reference to the accompanying drawings. In the technical field of constant velocity universal joints, a bar field type constant velocity universal joint may be called a Zeppa type constant velocity universal joint. FIG. 1 is a conceptual plan view of a vehicle 1 to which the present invention is applied. That is,
The vehicle 1 includes an engine 2, a transmission 3 for converting torque output from the engine 2, and a differential 4 connected to an output side of the transmission 3. On the output side of differential 4,
A pair of drive shafts 5 are connected, and the pair of drive shafts 5 are connected to a front wheel 6. The pair of drive shafts 5 includes a constant velocity universal joint 7 connected to the differential 4 side, a shaft 8 connected to the constant velocity universal joint 7, and a Barfield constant velocity universal connecting the shaft 8 and the front wheel 6. And a joint 9. As the constant velocity universal joint 7, a type other than the bar field type, for example, a tripod type or a double offset type is used.

FIG. 2 is a sectional view showing the configuration of the Barfield constant velocity universal joint 9 connected to the left wheel 6 of FIG. The Barfield constant velocity universal joint 9 connected to the right wheel 6 in FIG. 1 is configured symmetrically to the Barfield constant velocity universal joint 9 shown in FIG. . The bar field type constant velocity universal joint 9 shown in FIG. 2 includes an inner race 10 and an outer race 11, six balls 12, and an annular retainer 13. Hereinafter, the configuration of these components and the positional relationship between these components and other components will be specifically described.

The inner race 10 is spline-fitted to one end of the shaft 8 and has a snap ring (not shown).
Thereby, the inner race 10 is positioned with respect to the longitudinal direction of the shaft 8. With the above configuration, the inner race 10 is rotatable about the first axis A1.

The outer race 11 is formed in a cylindrical shape, and the outer race 11 is arranged outside the inner race 10. A boss 14 is formed integrally with the outer race 11 at an end of the outer race 11 opposite to the shaft 8, and a shaft 15 is provided at an outer end of the boss 14. This shaft 15 is connected to the wheel 6 side. With the above configuration, the outer race 11 is rotatable about the second axis B1.

As described above, when the drive shaft 5 is mounted on the vehicle 1, the height of the outer race 11 on the wheel 6 side is lower than the height of the connection portion of the shaft 8 on the differential 4 side. Has become. In FIG. 2, the first axis A1 is shown for convenience.
And the second axis B1 are shown as being set substantially linearly.

FIG. 3 shows a first state in which a barfield type constant velocity universal joint 9 is attached to the vehicle 1.
This is a coordinate system that three-dimensionally shows the positional relationship between the axis A1, the second axis B1, and the ball 12. FIG. 4 is a two-dimensional coordinate system when the coordinate system shown in FIG. 3 is viewed from the wheel 6 on the left side in FIG.

In a state where the Barfield constant velocity universal joint 9 is attached to the vehicle 1, as shown in FIG.
The axis A1 and the second axis B1 intersect and a predetermined joint angle θ1 is set. Then, an x-axis and ay-axis that are orthogonal to each other are set on a bisecting plane C1 that bisects the angle between the first axis A1 and the second axis B1, and z that is orthogonal to the bisecting plane C1 The axis is set. The first axis A1 and the second axis B1 are arranged in a plane including the x axis and the z axis.

FIG. 5 is a side view of the inner race 10 viewed from the differential 4 side. Inner race 10
On the outer periphery of are formed six inner grooves 16 at equal intervals in the circumferential direction. As shown in FIG. 2, the cross-sectional shape of each inner groove 16 in a plane including the first axis A <b> 1 is formed in an arc shape protruding toward the outer peripheral side of the inner race 10. Then, the center of curvature D1 of each inner groove 16 is set to 2 in a plane including the first axis A1.
It is offset to one of the intersections E1 between the equal plane C1 and the first axis A1. The shape of the side surface of each inner groove 16 is substantially semicircular.

FIGS. 6 and 7 are schematic plan views showing the structure of the inner race 10. FIG. FIG. 6 shows the shape of the inner grooves 16 arranged at every other position in the circumferential direction among the inner grooves 16 of FIG. The inner groove 16 in FIG. 7 is adjacent to the inner groove 16 in FIG.

The inner groove 16 shown in FIG. 6 has a front portion in the length direction formed in a spiral direction on the outer periphery of the inner race 10. Specifically, the center line F1 in the width direction of the inner groove 16 is formed linearly, and the center line F1 is inclined at an angle α1 with respect to the first axis A1. That is, the end of the inner groove 16 on the differential 4 side is located forward of the first axis A1 in the rotation direction J1 of the inner race 10, and the end of the inner groove 16 on the wheel 6 side is In the rotation direction J1,
It is located behind the first axis A1.

The center line F1 of the inner groove 16 shown in FIG. 7 is also inclined at an angle α1 with respect to the first axis A1. The inclination direction of the inner groove 16 in FIG.
Of the inner groove 16 is set in the opposite direction.
That is, all of the inner grooves 16 adjacent to each other are
It is configured symmetrically with respect to a plane (not shown) including the first axis A <b> 1, passing through the middle between the inner grooves 16.

On the other hand, on the inner periphery of the outer race 11, six outer grooves 17 are formed at equal intervals in the circumferential direction. Each outer groove 17 has a cross-sectional shape in a plane including the second axis B <b> 1 in an arc shape protruding toward the outer peripheral side of the outer race 11. And
In the plane including the second axis B1, each outer groove 17
Is offset to the other of the intersections E1 between the bisector C1 and the second axis B1. That is, the center of curvature D1 and the center of curvature G1 are arranged on both sides of the intersection E1 between the first axis A1 and the second axis B1. Further, the side surface shape of each outer groove 17 is configured to be substantially semicircular.

FIG. 8 is a schematic development view showing the outer peripheral surface shape of the outer race 11. Each outer groove 17 is formed in a spiral direction on the inner periphery of the outer race 11.
The adjacent outer grooves 17 are inclined in opposite directions. Specifically, the inner groove 1 shown in FIG.
An outer groove 17 for holding the ball 12 in cooperation with 6 is shown on the left side of FIG.

An outer groove 17 for holding the ball 12 in cooperation with the inner groove 16 shown in FIG. 7 is shown on the right side of FIG. That is, the center line H1 in the width direction of each outer groove 17 is inclined at an angle β1 with respect to the second axis B1. That is, all of the outer grooves 17 adjacent to each other pass through the middle between the outer grooves 17 and are symmetric with respect to a plane (not shown) including the second axis B1.

The retainer 13 is formed with six ball retaining holes 18 at equal intervals in the circumferential direction, penetrating the retainer 13 in the thickness direction. The shape of each ball holding hole 18 is substantially rectangular in a plane orthogonal to the bisector C1. In a state where each ball 12 is arranged in each ball holding hole 18, a part of each ball 12 is arranged in the inner groove 16 and the outer groove 17, respectively.

On the other hand, the shaft 8 is arranged inside a bellows-shaped boot (not shown). One end of the boot is fixed to the outer periphery of the opening of the outer race 11, and the other end of the boot is fixed to the shaft 8. These boots seal the internal space of the Barfield type constant velocity universal joint 9, and the sealed space is filled with grease (not shown) for lubricating heat generation and abrasion sites.

The inner race 10 and the outer race 11 are made of a material such as carbon steel or chrome steel. The retainer 13 is made of a material such as chrome steel, and the ball 12 is made of a material such as bearing steel. Further, the shaft 8 is made of a material such as carbon steel, carbon steel pipe, or boron steel. The shaft 8 and the inner race 1
The materials constituting the outer race 11, the outer race 11, the ball 12, and the cage 13 are all subjected to heat treatment. That is, induction hardening is applied to the medium carbon steel, and carburizing and quenching is applied to the low carbon steel. In this way, by hardening the surface of various materials, each component has the necessary strength for transmitting the torque.

Next, the traveling operation of the vehicle 1 shown in FIG. 1 will be described. The torque output from the engine 2 is transmitted to each drive shaft 5 via a transmission 3 and a differential 4. More specifically, the torque transmitted to shaft 8 is transmitted to outer race 11 via inner race 10 and ball 12. Here, when each drive shaft 5 rotates in the direction of arrow J1, the torque is transmitted to the wheels 6 and the vehicle 1
Moves forward in the direction of arrow K1.

The operation of the Barfield constant velocity universal joint 9 during the transmission of the torque will be described in detail by taking the Barfield constant velocity universal joint 9 arranged on the left side of FIG. 1 as an example. That is, when the shaft 8 rotates in the direction of the arrow J1, the inner race 10 rotates in the direction of the arrow J1, as shown in FIG. 4, FIG. 6, and FIG.

Then, a Barfield type constant velocity universal joint 9
In, the center of curvature D1 of the inner groove 16 and the center of curvature G1 of the outer groove 17 are offset with respect to the intersection E1, and each ball 12 is held by the holder 13. For this reason, the center M1 of each ball 12 is
And a circular locus N in the bisector C1 as shown in FIG.
1 around the intersection E1.

As a result, constant speed rotation of the shaft 8, the inner race 10, and the outer race 11 is achieved. Then, during rotation of the inner race 10 and the outer race 11, each ball 12 revolves around the intersection E1, and the ball 12 moves along the inner groove 16 and the outer groove 17.

When torque is transmitted from the inner race 10 to the outer race 11, a predetermined load is applied to the contact between each ball 12 and the inner groove 16 and the outer groove 17. Hereinafter, the inner groove 16 and the ball 1
The load acting on the contact point with the contact 2 will be described geometrically.

First, since the center of curvature D1 of the inner groove 16 and the center of curvature G1 of the outer groove 17 are offset on both sides of the intersection E1, the contact point between each ball 12 and the inner groove 16 is three-dimensionally displaced. I do. In other words, on the inner groove 16 side, the inner race 10 points to the arrow J1.
When rotated in the direction shown in FIG.
A contact point Q1 between the inner groove 16 and the inner groove 16 is set at a position other than the bisector C1. Therefore, the ball 12 moves along the trajectory N1.
, The load acting on the contact point Q1 between each ball 12 and the inner groove 16 constantly fluctuates in the x-axis, y-axis, and z-axis directions.

Next, the maximum value of the load generated at the contact point Q1 between each ball 12 and the inner groove 16 will be described.
The maximum value of this load is, as shown in FIG.
Is determined by the balance of the product (moment) of the load P1 and the length L1 of the orthogonal line L2. here,
The orthogonal line L2 represents a line segment set at a right angle from the intersection E1 to the line of action of the load P1, that is, the moment arm.

In this embodiment, as shown in FIG. 3, the first axis A1 and the second axis B1 are arranged in a plane including the x-axis and the z-axis. Therefore, the center M of the ball 12
When 1 is located at the longitudinal end (upper side in FIG. 6) of the inner groove 16, the component in the x-axis direction becomes maximum.

When the center M1 of the ball 12 moves to the longitudinal center of the inner groove 16 with the rotation of the inner race 10 and the outer race 11, the component 1 in the y-axis direction becomes maximum. Further, the center M1 of the ball 12
Moves to the longitudinal end (the lower side in FIG. 6) of the inner groove 16, the component in the x-axis direction becomes minimum.

Thereafter, as the inner race 10 and the outer race 11 rotate, the moving direction of the ball 12 is reversed. Then, when the center M1 of the ball 12 reaches the center in the length direction of the inner groove 16, the component in the y-axis direction becomes minimum. Further, the center M1 of the ball 12
However, when it returns to the longitudinal end (upper side in FIG. 6) of the inner groove 16, the component in the x-axis direction becomes maximum.

As described above, while the inner race 10 and the outer race 11 make one rotation, the ball 1
2 reaches the center of the inner groove 16 in the longitudinal direction,
That is, it is confirmed that the load P1 of the contact point Q1 between the ball 12 and the inner groove 16 becomes maximum when the component in the y-axis direction of the center M1 of the ball 12 becomes maximum as shown in FIG. I have.

According to this embodiment, each inner groove 16 is formed on the outer periphery of the inner race 10 in a spiral direction. Further, all of the adjacent inner grooves 16 pass through the middle between the inner grooves 16 and are symmetric with respect to a plane including the first axis A1.

For this reason, the inner groove 16 shown in FIG.
In the above, the ball 1 having the rotation phase at which the load P1 is maximized
For 2, the length L1 of the orthogonal line L2 is set as long as possible. Since the moment is constant, the absolute value of the component of the vector in the x-axis direction with respect to the bisector C1 is set as large as possible, and the load P1 at the contact point Q1 is suppressed as much as possible.

As shown in FIG. 8, on the outer race 11, the contact point between the ball 12 and the outer groove 17 is displaced along the center line H1. The maximum value of the load acting on the contact point between the outer groove 17 holding the ball 12 and the ball 12 in cooperation with the inner groove 16 shown in FIG. It is suppressed by the same action as the side.

As described above, at the contact point Q1 between each ball 12 and the inner groove 16 and at the contact point between each ball 12 and the outer groove 17, the occurrence of fatigue and peeling is reduced. Therefore, the Barfield constant velocity universal joint 9
The durability and the torque transmission function are improved. In addition, vibration of the barfield type constant velocity universal joint 9 and muffled noise during operation are suppressed.

When the left and right Barfield type constant velocity universal joints 9 are separately viewed from the differential 4 side,
The direction of rotation is reversed. For this reason, a barfield type constant velocity universal joint in which the inner groove and the outer groove are respectively inclined only in one direction is configured, and when the barfield type constant velocity universal joint is attached to each of the left and right drive shafts, In the Barfield type constant velocity universal joint described above, durability is improved by the same operation as described above.

However, in the other Barfield type constant velocity universal joint, since the rotation direction is reversed, the length of the above-described orthogonal line is as short as possible. As a result, the durability of the other Barfield constant velocity universal joint may be reduced. This problem can be avoided by setting the inclination directions of the inner groove and the outer groove of the Barfield constant velocity universal joint attached to the left and right drive shafts to be opposite to each other. However, when this configuration is employed, a barfield type constant velocity universal joint having a different configuration must be separately attached to the left and right drive shafts, and there is a new problem that the number of types of parts increases.

On the other hand, in this embodiment, the adjacent inner grooves 16 pass through the middle between the inner grooves 16 and are symmetric with respect to a plane including the first axis A1. ing. Further, all of the adjacent outer grooves 17 pass through the middle between the outer grooves 17 and are symmetric with respect to a plane including the second axis B1.

Therefore, in the Barfield constant velocity universal joint 9 arranged on the right side of FIG. 1, the inner groove 16 shown in FIG. 7, the outer groove 17 corresponding to the inner groove 16, and the inner groove With the ball 12 held by the groove 16 and the outer groove 17, the same operational effects as those of the bar-field type constant velocity universal joint 9 arranged on the left side in FIG. 1 can be obtained.

That is, according to this embodiment, even if one type (the same structure) of the Barfield constant velocity universal joint 9 is attached to either the left or right drive shaft 5, each of the Barfield constant velocity universal joints 9 can be used. The durability and transmission function of the torque are kept substantially the same. Therefore, there is no need to attach different types (different structures) of Barfield type constant velocity universal joints corresponding to the left and right drive shafts, and only one type of Barfield type constant velocity universal joint needs to be attached.

FIGS. 9 and 10 show the inner race 10.
FIG. 9 is a conceptual plan view showing another configuration example of FIG. 9 and 10, the upper side corresponds to the differential 4 side, and the lower side corresponds to the wheel 6 side. 6 and 7 in the inner race 10 of FIGS.
The same components as those of the inner race 10 are denoted by the same reference numerals, and description thereof will be omitted.

The inner groove 18 shown in FIG. 9 has a part in the length direction spirally formed with respect to the inner race 10. That is, the inclination of the center line R1 of the inner groove 18 with respect to the first axis A1 at the angle α1 is set at the center in the length direction. Further, at both ends in the length direction of the inner groove 18, the center line R1 and the first
The axis A1 is set substantially parallel. Further, the end of the inner groove 18 on the side of the differential 4 is aligned with the first axis A in the rotation direction J1 of the inner race 10.
1 and the wheel 6 in the inner groove 18.
The end on the side is located behind the first axis A <b> 1 in the rotation direction J <b> 1 of the inner race 10.

The inner groove 18 shown in FIG.
Are formed in a meandering shape like the inner groove 18 shown in FIG. Then, the inner groove 18 shown in FIG. 9 and the inner groove 18 shown in FIG.
0 are alternately arranged on the outer periphery. That is, all of the adjacent inner grooves 18 pass through the middle between the inner grooves 18 and are symmetric with respect to a plane including the first axis A1.

FIG. 11 is a developed view showing the structure of the outer race 11 corresponding to the inner race 10 of FIGS. 9 and 10. All of the outer grooves 19 formed on the outer periphery of the outer race 11 shown in FIG. 11 and adjacent to each other are inclined in the opposite direction. Specifically, an outer groove 19 for holding the ball 12 in cooperation with the inner groove 18 of FIG. 9 is shown on the right side of FIG.

An outer groove 19 for holding the ball 12 in cooperation with the inner groove 18 of FIG. 10 is shown on the left side of FIG. Then, in FIG. 11, the center line S1 in the width direction of the left outer groove 19 is inclined at an angle α1 with respect to the second axis B1 at the center in the length direction. FIG.
At the both ends in the length direction of the left outer groove 19, the center line S1 and the second axis B1 are set substantially parallel.

Further, in FIG. 11, the center line S1 in the width direction of the right outer groove 19 is inclined at an angle α1 with respect to the second axis B1 at the center in the length direction. In FIG. 11, at both ends in the length direction of the right outer groove 19, the center line S1 and the second axis B1 are set substantially parallel. In FIG. 11, the left outer groove 1 is shown.
9 and the inclination direction of the right outer groove 19 are set oppositely. That is, the adjacent outer groove 1
All of the members 9 pass through the middle between the outer grooves 19 and are symmetric with respect to a plane including the second axis B1.

When the inner race 9 and the outer race 11 shown in FIGS. 9 to 11 are used, the same operation and effect as those of the inner race 9 and the outer race 11 shown in FIGS. 5 to 8 can be obtained. In the inner race 10 of FIGS. 9 and 10, the center line R1 of the inner groove 18 is set substantially parallel to the first axis A1 at both ends in the length direction. Further, in the outer race 11 of FIG. 11, the center line S1 of the outer groove 19 is set substantially parallel to the second axis B1 at both ends in the length direction.

For this reason, the ball 1 held in the inner groove 18 in FIG. 9 and the outer groove 19 on the right side in FIG.
2 moves to the longitudinal ends of the inner groove 18 and the outer groove 19, the orthogonal line L2 shown in FIG.
Is set to be longer than in the case of FIG. For this reason, the load at the contact point is further suppressed.

FIGS. 12 and 13 show the inner race 1.
FIG. 11 is a conceptual plan view showing another example of the configuration of the No. 0. 12 and 13, the upper side corresponds to the differential 4 side, and the lower side corresponds to the wheel 6 side. FIG.
Also, in the inner race 10 of FIG. 13, the same components as those of the inner race 10 of FIGS. 6 and 7 are denoted by the same reference numerals, and description thereof will be omitted.

The entire length of the inner groove 20 shown in FIG. 12 is spirally formed with respect to the inner race 10. That is, the center line T1 of the inner groove 20 is aligned with the first axis A1 at the center in the length direction.
Is set at an angle α1. Also, at both ends in the length direction of the inner groove 20, the center line T1 is
It is inclined by an angle γ1 with respect to a line segment U1 parallel to the first axis A1. Here, the inner groove 20 with respect to the first axis A1
And the inclination directions of both ends of the inner groove 20 with respect to the first axis A1 are set opposite to each other.

Further, the end of the inner groove 20 on the differential 4 side is located forward of the first axis A1 in the rotation direction J1 of the inner race 10, and the end of the inner groove 20 on the wheel 6 side is In the rotation direction J1 of the race 10, it is located behind the first axis A1. That is, the inner groove 20 has a meandering shape as a whole.

The inner groove 20 shown in FIG.
The inner groove 20 has a meandering shape like the inner groove 20 shown in FIG. The inclination direction of the inner groove 20 shown in FIG. 13 is set opposite to the inclination direction of the inner groove 20 shown in FIG. Then, the inner groove 20 of FIG.
And the inner groove 20 of FIG.
Are arranged alternately on the outer circumference of the. That is, all of the adjacent inner grooves 20 pass between the inner grooves 20 and are symmetric with respect to a plane including the first axis A1.

FIG. 14 is a developed view showing the structure of the outer race 11 corresponding to the inner race 10 shown in FIGS. Outer grooves 21 formed on the outer periphery of the outer race 11 shown in FIG.
All of them are inclined in opposite directions. In particular,
An outer groove 21 for holding the ball 12 in cooperation with the inner groove 20 of FIG. 12 is shown on the right side of FIG.

An outer groove 21 for holding the ball 12 in cooperation with the inner groove 20 of FIG. 13 is shown on the left side of FIG. The center line V in the width direction of the outer groove 21
1 is inclined at an angle α1 with respect to the second axis B1 at the central portion in the longitudinal direction. Also, the center line V of each outer groove 21
1 are inclined at an angle γ1 with respect to the first axis A1 at both ends in the longitudinal direction. That is, the inclination direction of the outer groove 21 shown on the left side of FIG. 14 is set opposite to the inclination direction of the outer groove 21 shown on the right side of FIG.
In other words, all of the adjacent outer grooves 21 are
It passes through the middle between the outer grooves 21 and is symmetric with respect to a plane including the second axis B1.

When the inner race 9 and the outer race 11 shown in FIGS. 12 to 14 are used, the same operation and effect as those of the inner race 9 and the outer race 11 of FIGS. 5 to 8 can be obtained. FIG.
In the inner race 10 of FIG. 13, the center line T1 of the inner groove 21 is inclined at an angle γ1 with respect to the first axis A1 at both ends in the length direction. Further, FIG.
In the outer race 11, the center line V1 of the outer groove 21 is inclined at an angle γ1 with respect to the second axis B1 at both ends in the length direction.

Therefore, when the ball 12 held in the inner groove 21 of FIG. 12 and the outer groove 21 on the right side of FIG. 14 moves to the longitudinal ends of the inner groove 21 and the outer groove 21, The orthogonal line L shown in FIG.
The length L1 is set to be longer than in the case of FIG. For this reason, the load at the contact point is further suppressed.

Although not particularly shown, at least one pair of the adjacent inner grooves is configured to pass through the middle between the inner grooves, and at least one pair of the adjacent outer grooves is It is also possible to adopt a configuration passing through the middle between the outer grooves. Also,
The shape and inclination angle of the inner groove of the inner race,
The shape and the inclination angle of the outer groove of the outer race are set based on the dimensions of each part of the barfield type constant velocity universal joint 9 and the like. Further, the barfield type constant velocity universal joint of the present invention can be applied to a propeller shaft.

[0073]

As described above, according to the first aspect of the present invention,
During rotation of the inner race and the outer race, the load acting on the contact point between each ball and the inner groove and the contact point between each ball and the outer groove is suppressed.
Therefore, fatigue and peeling of the contact portion are reduced, and the durability and torque transmission function of the Barfield type constant velocity universal joint are improved. Further, vibration and muffled noise during rotation of the inner race and the outer race are suppressed.

At least one pair of adjacent inner grooves passes through the middle between the inner grooves, and
Further, it is configured to be plane-symmetric with respect to a plane including the first axis. Furthermore, at least one set of adjacent outer grooves passes through the middle between the mutual outer grooves,
Further, it is configured to be plane-symmetric with respect to a plane including the second axis. For this reason, one type (the same structure) of a barfield type constant velocity universal joint is used in a vehicle power transmission device.
Even when they are attached to locations that rotate in mutually opposite directions, the durability and torque function of each Barfield constant velocity universal joint are maintained substantially the same. Therefore, it is sufficient to attach one type of Barfield type constant velocity universal joint to each attachment site.

According to the second aspect of the invention, in addition to the same effect as the first aspect, the balls held in the inner groove and the outer groove move to both ends in the length direction of the inner groove and the outer groove. In this case, the length of the orthogonal line, that is, the arm of the moment becomes longer. For this reason,
The maximum value of the load acting on the contact point between the inner groove and the outer groove and the ball can be made more uniform.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a schematic configuration of a vehicle to which the present invention is applied.

FIG. 2 is a sectional view showing an embodiment of the present invention.

FIG. 3 is a coordinate system geometrically showing the Barfield constant velocity universal joint shown in FIG. 2;

FIG. 4 is a coordinate system geometrically showing the Barfield constant velocity universal joint shown in FIG. 2;

FIG. 5 is a side view of the inner race of the Barfield constant velocity universal joint shown in FIG. 2 as viewed from a differential side.

FIG. 6 is a conceptual plan view showing an inner race of the Barfield constant velocity universal joint shown in FIG. 2;

FIG. 7 is a conceptual plan view showing an inner race of the Barfield constant velocity universal joint shown in FIG. 2;

FIG. 8 is a development view showing an outer race of the barfield type constant velocity universal joint shown in FIG. 2;

FIG. 9 is a conceptual plan view showing another configuration example of the inner race in the present invention.

FIG. 10 is a conceptual plan view showing another configuration example of the inner race in the present invention.

FIG. 11 is a development view showing an outer race corresponding to the inner race of FIGS. 9 and 10;

FIG. 12 is a conceptual plan view showing still another configuration example of the inner race in the present invention.

FIG. 13 is a conceptual plan view showing still another configuration example of the inner race in the present invention.

FIG. 14 is a development view showing an outer race corresponding to the inner race of FIGS. 12 and 13.

[Explanation of symbols]

10 ... Inner race, 11 ... Outer race, 1
2 ... ball, 13 ... retainer, 16, 18, 20 ... inner groove, 17, 19, 21 ... outer groove, C1 ... 2
Equal surface, D1, G1 ... center of curvature.

Continued on the front page (72) Inventor Yukihiro Tanigawa 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Automobile Co., Ltd. (72) Inventor Gouge Sugiura 41 No. 41, Chukumi-ji, Oji, Nagakute-cho, Aichi-gun, Aichi Prefecture 1 Toyota Corporation Central Research Institute (56) References JP-A-6-50351 (JP, A) JP-A-7-91458 (JP, A) JP-A-9-317783 (JP, A) JP-B-52-20625 (JP, A) B1) (58) Field surveyed (Int. Cl. ⁷ , DB name) F16D 3/22-3/24

Claims (2)

(57) [Claims] 1. An inner race having a plurality of inner grooves formed on an outer peripheral surface, an outer race disposed outside the inner race and having a plurality of outer grooves formed on an inner peripheral surface; A plurality of balls arranged in each set with the inner groove and the one outer groove as one set, and a plurality of balls arranged between the inner race and the outer race, and a first axis of the inner race and the outer race; An annular retainer for retaining the center of the ball on a bisecting surface that bisects the angle formed by the second axis, and a center of curvature of the inner groove in a plane including the first axis; In a Barfield type constant velocity universal joint, a center of curvature of the outer groove in a plane including the second axis is offset on both sides of the bisector. At least a part of the inner groove is formed in a spiral direction on an outer periphery of the inner race, and at least a part of the plurality of outer grooves is formed in a spiral direction on an inner periphery of the outer race. At least one pair of the grooves is formed symmetrically with respect to a plane including the first axis, passing through the middle between the inner grooves, and at least one pair of the adjacent outer grooves is formed. A barfield type constant velocity universal joint which passes through a middle between the outer grooves and is symmetric with respect to a plane including the second axis. 2. An inclination direction of a central portion of the plurality of inner grooves in a length direction with respect to the first axis is different from an inclination direction of both ends of the plurality of inner grooves in a length direction with respect to the first axis. In addition, the inclination direction of the central portion in the length direction of the plurality of outer grooves with respect to the second axis is different from the inclination direction of both end portions in the length direction of the plurality of outer grooves with respect to the second axis. The Barfield type constant velocity universal joint according to claim 1, wherein: