KR20220099762A - Constant velocity joint - Google Patents

Abstract

Disclosed is a constant velocity joint. According to one embodiment of the present invention, different curved tracks are formed alternately, and thus torque transmission efficiency and a selective ball control force are generated. The constant velocity joint of the present invention comprises: an outer ring (100); an inner ring (200); a plurality of balls (300); and a cage (400).

Description

Constant velocity joint

The present invention relates to a constant velocity joint, and more particularly, to a constant velocity joint having improved torque transmission efficiency and cage strength.

In general, the joint is for transmitting rotational power (torque) to the rotational shafts having different angles of rotation. In the case of a propulsion shaft with a small power transmission angle, a hook joint or a flexible joint is used, and the drive shaft of a front-wheel drive vehicle with a large power transmission angle In this case, a constant velocity joint is used.

The constant velocity joint is mainly used for the axle shaft of an independent suspension front-wheel drive vehicle because it can smoothly transmit power at a constant speed even when the intersection angle between the drive shaft and the driven shaft is large, and the transmission side (inboard side) around the shaft is composed of a tripod type constant velocity joint or a slide type constant velocity joint, and the wheel side (outboard side) around the shaft is composed of a fixed ball type constant velocity joint.

A tripod-type constant velocity joint or slide-type constant velocity joint on the transmission side absorbs vehicle displacement through axial motion and angular motion, and a fixed ball-type constant velocity joint on the wheel side rotates as much as the steering angle of the wheel side to provide power at constant speed. to convey

The fixed ball type constant velocity joint described above is divided into a ball joint in which the track of the outer ring and the inner ring is composed only of curves and has a maximum cleavage angle of 47 degrees, and an undercut ball joint in which the track of the outer ring and the inner ring is composed of curves and straight lines and has a maximum cleavage angle of 50 degrees.

The conventional ball-type constant velocity joint for a vehicle has a structure in which a cage and an inner ring fix the ball, and the ball moves in a groove formed on the inner circumferential surface of the outer ring in the longitudinal direction according to steering.

For example, in the case of a constant velocity joint fastened to the hub side, it has a function of cutting according to the steering of the vehicle. Reduction of the turning radius of a vehicle in narrow road conditions was an important factor in vehicle development.

For example, in the case of a constant velocity joint fastened to the hub side, it has a function of cutting according to the steering of the vehicle. Reduction of the turning radius of a vehicle in narrow road conditions was an important factor in vehicle development.

The conventional constant velocity joint has a structure in which the groove radius of the outer ring and inner ring is offset from the center of rotation in the axial direction so that the ball can be provided with operability that can achieve constant velocity without jamming between the grooves. have.

In addition, in the conventional constant velocity joint, the size of the offset of the outer ring and the offset of the inner ring are the same and are symmetrical. It generates force to prevent jamming between the ball and the groove.

On the other hand, in this offset structure, the larger the joint angle, the greater the ball component in the axial direction, resulting in disadvantages in the strength of the cage and the torque transmission efficiency of the joint.

Republic of Korea Patent No. 10-1187529

Embodiments of the present invention are intended to provide a constant velocity joint with improved control force on the ball and improved torque transmission efficiency through a constant velocity joint composed of different curved tracks inside the constant velocity joint.

The constant velocity joint according to an embodiment of the present invention is coupled to the drive shaft receiving the rotational power of the engine and extends from the inner peripheral surface to the outer ring curved track (S1) along the outer side away from the drive shaft (100); an inner ring 200 installed inside the outer ring 100 and extending from the inside of the outer circumferential surface to the inner ring curved track S2 along the outside; A plurality of balls 300 in rolling contact between the outer ring 100 and the inner ring 200 in order to transmit the rotational power of the outer ring 100 to the inner ring 300; and a cage 400 supporting the ball 300, wherein the outer ring 100 and the inner ring 200 have the outer ring curved track S1 and the inner ring curved track S2 of the cage 400. Alternately formed differently along the circumferential direction.

The outer ring 100 and the inner ring 200 are at a first position P1, the radius center Ro of the outer ring curved track S1 and the radius center Ri of the inner ring curved track S2 are constant velocity joints is located at the center (CO) of the first position (P1) adjacent to the second position (P2) spaced apart from the clockwise direction in the X-axis direction with respect to the center (CO) of the constant velocity joint A first offset (f1) spaced apart by a distance and located at the center (C1) of the outer ring 100, and the first offset (f1) based on the center (CO) of the constant velocity joint in the opposite direction in the X-axis direction spaced apart from each other by the same distance, and under the condition that the second offset f2 at which the center C2 of the inner ring 200 is located is maintained, the radius center Ro of the outer ring curved track S1 is the outer ring 100 ), and the radial center Ri of the inner ring curved track S2 is located at the center C2 of the inner ring 200 .

The outer ring 100 and the inner ring 200 are not offset in the X-axis direction with respect to the center CO of the constant velocity joint at the first position P1.

In the outer ring 100 and the inner ring 200 , the first offset f1 and the second offset f2 are spaced apart from each other by the same distance at the second position P2 .

At the first position P1, the ball contact force Fo1 of the outer ring curved track S1 with respect to the ball 300 and the ball contact force Fi1 of the inner ring curved track S2 are applied to the ball 300. It is generated in the center direction perpendicular to the axial direction ball component force (Fc1) is characterized in that the movement is made without being caught in the ball 300 in a non-generated state.

In the first position (P1), the funnel angle of the ball 300 is characterized in that any one angle selected from a minimum of 0 degrees and a maximum of 3 degrees or less.

In the second position (P2), the funnel angle of the ball 300 is characterized in that any one angle selected from a minimum of 9 degrees and a maximum of 10 degrees or less.

The ball 300 is characterized in that in the second position (P2), the cage 400 is regulated to a half angle of the jeep angle.

The centers C1 and C2 of the outer ring 100 and the inner ring 200 are located below the center CO of the constant velocity joint at the second position P2 based on the center of the ball 300. do it with

The present embodiments form different curved tracks at the first position and the second position, so that the axial component force according to the movement of the ball is generated differently depending on the position, thereby improving the torque transmission efficiency.

The present embodiments can improve the strength of the cage even when the angle of cut is increased, and it is possible to prevent pinching of the ball while maintaining the constant velocity performance.

The present embodiments can be used to promote stable operation of the constant velocity joint by changing the ball's regulating force according to the position.

1 is an exploded perspective view of a constant velocity joint according to the present embodiment.
Figure 2 is a front view of the constant velocity joint according to the present embodiment.
Figure 3 is a cross-sectional view taken along line CC of Figure 2;
FIG. 4 is a cross-sectional view taken along line DD of FIG. 2 .
5 is a view showing the movement trajectory of the ball at the first position (P1) according to the present embodiment.
6 is a view showing an example of the contact force of the cage at the first position P1 according to the present embodiment.
7 is a view showing a jeep angle according to the movement of the ball in the second position (P1) according to the present embodiment.
8 is a view showing another embodiment of the second position.

A constant velocity joint according to an embodiment of the present invention will be described with reference to the drawings. 1 is an exploded perspective view of a constant velocity joint according to an embodiment of the present invention, FIG. 2 is a front view of the constant velocity joint according to this embodiment, and FIG. 3 is a cross-sectional view taken along line C-C of FIG. 2 is a cross-sectional view taken along the line D-D, and FIG. 5 is a view showing the movement trajectory of the ball at the first position P1 according to the present embodiment.

1 to 7, the constant velocity joint according to this embodiment improves the torque transmission efficiency through the constant velocity joint composed of different curved tracks alternately along the circumferential direction of the cage 400, and the axial direction of the ball Provides a constant velocity joint with reduced component forces and reduced unnecessary friction.

To this end, in this embodiment, the outer ring 100 is coupled to the drive shaft receiving rotational power of the engine and extends from the inner circumferential surface to the outer ring curved track S1 along the outer side away from the drive shaft, and the outer ring 100. The inner ring 200 is installed inside and extends from the inside of the outer circumferential surface to the inner ring curved track S2 along the outside, and the outer ring 100 and the outer ring 100 to transmit the rotational power of the outer ring 100 to the inner ring 300 A plurality of balls 300 in rolling contact between the inner ring 200 and a cage 400 supporting the balls 300 are included.

In addition, the outer ring 100 and the inner ring 200 are alternately formed such that the outer ring curved track S1 and the inner curved curved track S2 are alternately formed along the circumferential direction of the cage 400 .

For example, the first position P1 corresponds to a position in the 12 o'clock direction in FIG. 2 , the second position P2 corresponds to a position in the 2 o'clock direction, and the second position P2 located in the 2 o'clock direction is a reference. The new first position P1 corresponds to the 4 o'clock position. As described above, the first position P1 and the second position P2 are alternately arranged.

The outer ring curved track S1 and the inner curved curved track S2 may extend as shown in the drawings, and adjacent to the first position P1 and at a second position P2 spaced apart from each other in a clockwise direction. A first offset f1 spaced apart by a predetermined distance in the X-axis direction based on the center CO of the constant velocity joint and the center C1 of the outer ring 100 is located, and the center CO of the constant velocity joint In the condition that the first offset f1 and the second offset f2 at which the center C2 of the inner ring 200 is located are maintained, the first offset f1 and the second offset f2 are spaced apart from each other by the same distance in the opposite direction in the X-axis direction. The radius center Ro of the curved track S1 is located at the center C1 of the outer ring 100, and the radius center Ri of the inner ring curved track S2 is the center C2 of the inner ring 200. is located in

The reason for having the outer curved track S1 and the inner curved track S2 different from each other at the first position P1 and the second position P2 as described above is to improve torque transmission efficiency.

For example, while the outer ring curved track S1 and the inner ring curved track S2 are alternately arranged at the first and second positions P1 and P2, the friction with the ball 300 is reduced at the first position P1, The friction between the window and the ball 300 opened in the cage 400 and the torque loss due to the friction between the inner and outer diameters of the cage 400 can be reduced together, so that the overall torque transmission efficiency is improved.

In particular, in this embodiment, the torque loss caused by the friction between the window of the cage 400 and the ball 300 and the friction between the inner and outer diameters of the cage 400 is mainly generated by the axial ball component of the ball 300. By reducing the two, the torque transmission efficiency can be improved more efficiently.

The outer ring 100 and the inner ring 200 are not offset in the X-axis direction with respect to the center CO of the constant velocity joint at the first position P1.

The ball 300 has an outer curved track S1 and an inner curved track S2 as shown in the drawing, and the ball 300 is in rolling contact with the outer curved track S1 and the inner curved track S2. as it moves

In particular, in the constant velocity joint according to this embodiment, in the first position P1, the radius center Ro of the outer ring curved track S1 and the radius center Ri of the inner ring curved track S2 are the center of the constant velocity joint (CO) ) so that the ball 300 can be moved in a state where the funnel angle is not generated.

In this way, when the funnel angle is not generated, the axial component force of the ball 300 is not generated and is moved.

That is, the ball contact force Fo1 of the outer ring curved track S1 with respect to the ball 300 at the first position P1 and the ball contact force Fi1 of the inner ring curved track S2 are the ball 300 As shown by the arrow, it is generated in the vertical center direction, and the axial ball component Fc1 is not generated and moves without being caught by the ball 300 .

In this case, the ball 300 moves along the outer ring curved track S1 and the inner ring curved track S2 while drawing movement trajectories shown by dotted and solid lines and dotted lines.

At the first position P1 , any one angle selected from among the minimum angle of 0 degrees and the maximum of 3 degrees or less is maintained at the funnel angle of the ball 300 . The funnel angle is an angle at which the axial component force Fc1 is not generated in the ball 300 , and the torque transmission efficiency is improved, and the ball 300 is stably moved without being caught. For example, the axial component force Fc1 may be reduced by 50% or more compared to the conventional one.

In this case, the constant velocity joint does not have a regulating force on the ball 300 , but the contact force of the cage 400 is reduced and thus the friction is minimized.

Therefore, in the first position P1, the cage 400 can be used stably without a decrease in strength.

The outer ring 100 and the inner ring 200 have the first offset f1 and the second offset f2 spaced apart from each other by the same distance at the second position P2, and the outer ring curved track S1 ) is located at the center C1 of the outer ring 100, and the radius center Ri of the inner ring curved track S2 is located at the center C2 of the inner ring 200 As a result, the ball 300 moves along the outer ring curved track S1 and the inner ring curved track S2.

When the ball 300 moves along the outer and inner curved tracks S1 and S2 at the second position P2, the ball contact force Fo2 according to the contact with the outer curved track S1 and the inner curved track S2 ) of the ball contact force Fi2 is generated with respect to the ball 300 .

In addition, the ball 300 generates an axial component force Fc2 in the direction shown by the arrow and generates a regulating force for the ball 300, so that the design of the constant velocity joint desired by the designer can be more advantageously reflected.

In this case, the funnel angle of the ball 300 is maintained at any one angle selected from a minimum of 9 degrees and a maximum of 10 degrees or less. As an example, the angle at which the ball 300 is caught is at any one angle selected from at least 3 degrees to 9 degrees or less. It is possible to prevent jamming when moving along S1, S2).

As such, the present embodiment prevents damage through reduction of friction of the cage 400 by changing the regulatory force and torque transmission efficiency for the ball 300 at the first position P1 and the second position P2, and the cage ( 400), it is possible to reduce the shear stress by reducing the contact force.

The first and second offsets f1 and f2 are maintained around the PCD (Pitch Circle Diameter) of the ball 300 to generate a component force in the ball 300 to maintain the directionality, and to be caught due to tolerance between internal parts occurrence can be prevented.

In addition, since the center of the ball 300 is located on the constant velocity plane, it is possible to achieve stable operation of the ball joint.

Referring to the accompanying FIG. 7 , in the ball 300 according to the present embodiment, the cage 400 is regulated to a half angle of a cleavage angle at the second position P2 . In this case, the ball 300 generates an axial component force Fc2 so that the regulating force on the ball 300 is maintained, thereby compensating for the disadvantage in the first position P1 where there is no ball regulating force.

For reference, the notch refers to the degree of bending about the axis of the outer ring 100 on the ball joint side compared to the neutral state of the wheel, and the greater the cleavage, the lower the strength and durability.

Referring to FIG. 8, in this embodiment, the center (C1, C2) of the outer ring 100 and the inner ring 200 is different from the above-described embodiment at a second position ( In P2), it is located below the center (CO) of the constant velocity joint.

The centers C1 and C2 of the outer and inner rings 100 and 200 are spaced the same distance from each other by a third offset f3 and a fourth offset f4 based on the center CO of the constant velocity joint, and the constant velocity The center CO of the joint, the third offset angle f3α, and the fourth offset angle f4α are maintained.

And the radial center (Ro) of the outer ring collinear track and the radial center (Ri) of the inner ring curved track are maintained as shown in the drawings.

In the above, although an embodiment of the present invention has been described, those of ordinary skill in the art can add, change, delete or add components within the scope that does not depart from the spirit of the present invention described in the claims. The present invention may be variously modified and changed by such as, and it will be said that it is also included within the scope of the present invention.

100: outer ring
200: inner ring
300: ball
400 : cage
S1 : Outer ring curved track
S2 : Inner ring curved track

Claims (9)

an outer ring 100 coupled to a drive shaft receiving rotational power of the engine and extending from the inner circumferential surface to the outer ring curved track S1 along the outer side away from the drive shaft;
an inner ring 200 installed inside the outer ring 100 and extending from the inside of the outer circumferential surface to the inner ring curved track S2 along the outside;
A plurality of balls 300 in rolling contact between the outer ring 100 and the inner ring 200 in order to transmit the rotational power of the outer ring 100 to the inner ring 300; and
Including a cage 400 for supporting the ball 300,
The outer ring 100 and the inner ring 200 are constant velocity joints in which the outer ring curved track (S1) and the inner ring curved track (S2) are alternately formed differently along the circumferential direction of the cage (400). The method of claim 1,
The outer ring 100 and the inner ring 200 are at a first position P1, the radius center Ro of the outer ring curved track S1 and the radius center Ri of the inner ring curved track S2 are constant velocity joints is located at the center (CO) of
In the second position (P2), which is adjacent to the first position (P1) and spaced apart from each other in the clockwise direction, is spaced apart by a predetermined distance in the X-axis direction based on the center (CO) of the constant velocity joint and the outer ring (100) The first offset f1 at which the center C1 is located, and the first offset f1 and the first offset f1 based on the center CO of the constant velocity joint are spaced apart from each other by the same distance in the opposite direction in the X-axis direction, Under the condition that the second offset f2 at which the center C2 of the inner ring 200 is located is maintained, the radial center Ro of the outer ring curved track S1 is located at the center C1 of the outer ring 100 and , a constant velocity joint in which the radial center (Ri) of the inner ring curved track (S2) is located at the center (C2) of the inner ring (200). 3. The method of claim 2,
The outer ring 100 and the inner ring 200 are constant velocity joints in which an offset is not formed in the X-axis direction with respect to the center CO of the constant velocity joint at the first position P1. 3. The method of claim 2,
The outer ring 100 and the inner ring 200 are constant velocity joints in which the first offset f1 and the second offset f2 are spaced apart from each other by the same distance at the second position P2. The method of claim 1,
At the first position P1, the ball contact force Fo1 of the outer ring curved track S1 with respect to the ball 300 and the ball contact force Fi1 of the inner ring curved track S2 are applied to the ball 300. A constant velocity joint that is generated in the central direction perpendicular to the axial direction and moves without the ball 300 being caught in the state in which the axial ball component force (Fc1) is not generated. The method of claim 1,
In the first position (P1), the funnel angle of the ball 300 is a constant velocity joint, characterized in that any one angle selected from a minimum of 0 degrees and a maximum of 3 degrees or less. 6. The method of claim 5,
In the second position (P2), the constant velocity joint, characterized in that the funnel angle of the ball 300 is any one angle selected from a minimum of 9 degrees and a maximum of 10 degrees or less. 3. The method of claim 2,
The ball 300 is a constant velocity joint, characterized in that the cage 400 is regulated to a half angle of the angle in the second position (P2). 3. The method of claim 2,
The centers C1 and C2 of the outer ring 100 and the inner ring 200 are located below the center CO of the constant velocity joint at the second position P2 based on the center of the ball 300. constant velocity joint.

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