JP2574211Y2 - Zeppa type constant velocity joint - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION A Zeppa type constant velocity joint according to the present invention is, for example, a front-engine front-wheel drive vehicle (FF vehicle).
And used to transmit drive power from the transmission to the front wheels.

[0002]

2. Description of the Related Art A constant velocity joint is provided between a transmission and front wheels of a front-wheel drive vehicle so that the driving force of the engine can be transmitted to the front wheels, which are driving wheels, at the same angular velocity over the entire circumference regardless of the displacement of the wheels. And Conventionally, a Zeppa type constant velocity joint, which is a kind of constant velocity joint used for such a part, has been disclosed in, for example, Japanese Utility Model Laid-Open No. 57-145824.
No. 5, No. 59-185425, No. 62-12
No. 021 is known.

As shown in FIGS. 5 to 7, for example, such a conventionally known Zeppa constant velocity joint reduces the transmission of rotational force between an inner ring 2 and an outer ring 3 by an integral multiple of 3 (usually 6 times). Pieces)
Are configured to be performed through the balls 4 and 4. The inner ring 2 is fixed to the outer end of one shaft 5 driven to rotate by a transmission. Further, the outer wheel 3 fixes the front wheel, which is a driving wheel, to the outer end thereof, and fixes the front wheel to the inner end of the other shaft 6. On the outer peripheral surface of the inner ring 2, six inner engaging grooves 7 having an arc-shaped cross section are formed at regular intervals in the circumferential direction and at right angles to the circumferential direction. In addition, the outer ring 3
At a position facing the inner engaging grooves 7, 7 on the inner peripheral surface of
Six outer engagement grooves 8, also having an arc-shaped cross section, are formed in a direction perpendicular to the circumferential direction.

[0004] Between the outer peripheral surface 2a of the inner race 2 and the inner peripheral surface 3a of the outer race 3, a retainer 9 having an arc-shaped cross section and having an overall annular shape is displaceable with respect to the inner race 2 and the outer race 3. It is pinched. Pockets 10 and 10 are formed at positions corresponding to the inner and outer engagement grooves 7 and 8 at six positions in the circumferential direction of the retainer 9.
6 balls in total, 1 ball each inside 0, 10
4 is held. These balls 4, 4 are held in the pockets 10, 10, respectively.
It is free to roll along both outer engagement grooves 7 and 8. As shown in FIG. 7, each of the pockets 10 and 10 has an oval shape that is long in the circumferential direction, and the distance between the adjacent balls 4 and 4 changes with a change in the axis intersection angle θ described below. Even in such cases, this change can be absorbed.

Further, regardless of the displacement between the one shaft 5 and the other shaft 6, each of the balls 4, 4 is connected to the axis intersection angle θ between the two shafts 5, 6, ie, the center line of the one shaft 5. It is disposed in a bisecting plane c that bisects the angle θ between the two lines a and b at the intersection o between the center line b and the center line b of the other shaft 6. For this reason, the bottom surfaces 7a, 7a of the inner engagement grooves 7, 7 are located on the center line a,
Positioned on an arc centered on a point d separated by h from the intersection o, the bottom surfaces 8a, 8a of the outer engagement grooves 8, 8 are:
On the center line b, it is located on an arc centered on a point e, which is h from the intersection o. However, the inner ring 2
The outer peripheral surface 2a of the inner ring 2, the inner peripheral surface 3a of the outer ring 3, and the inner and outer peripheral surfaces of the cage 9 are respectively located on a spherical surface centered at the intersection point o, and the outer peripheral surface 2a of the inner ring 2 and the cage 9
And the inner peripheral surface 3a of the outer ring 3 and the outer peripheral surface of the retainer 9 can slide freely.

In the case of the Zepper type constant velocity joint 1 constructed as described above, when the inner ring 2 is rotated by the one shaft 5, this rotational motion is transmitted to the outer ring 3 via six balls 4, 4. , The other shaft 6 rotates. When the positional relationship between the two shafts 5 and 6 (the axis intersection angle θ) changes, the balls 4 and 4 roll along the inner and outer engagement grooves 7 and 8, respectively, and the one shaft 5 and the other shaft 6 are allowed to displace.

[0007]

In order to construct a Zepper type constant velocity joint which is constructed and operates as described above, the width dimension W of each pocket 10 provided in the retainer 9 is set as shown in FIG. When the outer diameter D of the ball 4 held in each pocket 10 is larger than the outer diameter D (W> D), at the time of starting and running of the automobile incorporating the Zeppa constant velocity joint 1,
The ball 4 collides with the inner surface of the pocket 10 and generates a hitting sound,
It may cause discomfort to passengers. For this reason, conventionally, the width W is equal to or slightly smaller than the outer diameter D (W ≦ D), and the ball 4 is slightly inserted into each pocket 10. He had a closing fee. However, in this case, the vibration is easily transmitted between the inner wheel 2 and the outer wheel 3, and the vehicle body vibrates at the time of idling of the engine, again giving the occupant a feeling of discomfort.

However, according to an experiment conducted by the inventor, even when a gap is provided between the pocket 10 and the ball 4 in order to avoid vibration, a tapping sound is always generated when the vehicle starts and runs. The gap is 25μm
When the joint angle (the positional relationship between the one shaft 5 and the other shaft 6 deviates from a linear state) of the Zeppa constant velocity joint 1 exceeds 25 degrees, the tapping sound is generated. It was understood that a problem occurred.

In order to prevent the occurrence of a tapping sound due to such a cause, the width W of the pocket 10 and the outer diameter D of the ball 4 must be equal (W = D), or the outside of the ball 4 must be equal. 25 for diameter
It is conceivable that the size is not more than the dimension obtained by adding μm (W ≦ D + 25 μm). However, in order to satisfy such conditions, high-precision finishing is required, which not only causes an increase in the manufacturing cost of the cage 9 but also causes vibration to be transmitted from the inner ring 2 to the outer ring 3. Vibration that occurs when the engine is idling is easily transmitted to the front wheels via the transmission, the one shaft 5, the inner ring 2, the balls 4, 4, the cage 9, the outer ring 3, and the other shaft 6. The vibration transmitted to the front wheels is further undesirably transmitted to the steering wheel via the steering device or transmitted to the vehicle body via the suspension device, causing uncomfortable feeling to the driver or the like. The Zeppa constant velocity joint of the present invention eliminates any of the disadvantages described above.

[0010]

A zepper type constant velocity joint according to the present invention has an inner ring fixed to one shaft end and an outer peripheral surface of the inner ring, similarly to the above-mentioned conventional zeppa type constant velocity joint. Are fixed at circumferentially equidistant positions and at integral multiples of 3, each having an inner engaging groove having an arc-shaped cross section formed in a direction perpendicular to the circumferential direction, and fixed to the end of the other shaft. An outer ring, an outer engaging groove having an arc-shaped cross section formed in a direction perpendicular to the circumferential direction at a position facing the inner engaging groove on an inner peripheral surface of the outer ring, and an outer peripheral surface of the inner ring. A retainer sandwiched between the inner peripheral surface of the outer ring and pockets formed at positions matching the inner and outer engagement grooves, and a pair of inner and outer engagement members held inside the respective pockets Consists of balls that are integral multiples of 3 and are allowed to roll freely along the groove.
Each ball is arranged in a bisecting plane of an axis intersection angle between the one axis and the other axis.

[0011] In particular, in the Zeppa constant velocity joint of the present invention, at least an intermediate portion of at least one of the inner surfaces of the pair of inner surfaces located on the opposite side in the axial direction of the cage.
By providing a stepped portion having a different inclination angle from the portion other than the intermediate portion, the width dimension of each pocket in the axial direction of the retainer is reduced by the outer diameter of the ball at a portion near the inner peripheral surface of the retainer. It is smaller than the size, and is larger than the outer diameter of the ball at least at the middle position in the inside and outside directions.

[0012]

The operation of the above-structured constant velocity joint of the present invention, which transmits rotational motion between the inner ring and the outer ring, is the same as that of the conventional constant velocity joint of the conventional type. The same is true. In particular, in the case of the zeppa type constant velocity joint of the present invention, when the joint angle is large and the tapping sound is easily generated, the ball at the position where the tapping sound is likely to be generated is located near the inner peripheral surface of the retainer. As it is displaced,
It is located in the narrow part of the pocket. As a result,
Even when the joint angle is large, the ball does not collide with the inner surface of the pocket, and no unpleasant hitting sound is generated. In addition, the remaining balls located at positions where it is difficult to make a hitting sound are located in a portion having a large width dimension in the pocket, as the ball is displaced from the middle portion in the outside direction of the retainer to a portion closer to the outer peripheral surface in the pocket. I do. Therefore, vibration is not easily transmitted between the inner ring and the outer ring. In particular, when no steering angle is applied to the front wheels, all the balls are located in the pocket in the middle portion in the inward and outward directions of the cage, so that the transmission of vibration between the inner wheel and the outer wheel is prevented. Effectively achieved.

[0013]

FIG. 1 shows a first embodiment of the present invention.
As in the case of the above-mentioned conventional Zeppa constant velocity joint, the Zeppa type constant velocity joint of the present invention is provided on the inner end of the other shaft 6 having the front wheel connected to the outer end as shown in FIGS. An outer ring 3 to be fixed, outer engagement grooves 8, 8 having an arc-shaped cross section formed at six equally spaced positions on an inner peripheral surface 3a of the outer ring 3 and each formed in a direction perpendicular to the circumferential direction; Inner ring 2 fixed to the outer end of one shaft 5 that rotates based on the driving force from the inner ring 2, and positions facing the outer engaging grooves 8 at six positions on the outer peripheral surface 2a of the inner ring 2 Inner engaging grooves 7, 7 formed in a direction perpendicular to the circumferential direction and having an arc-shaped cross section; an outer peripheral surface 2a of the inner ring 2;
Pockets 10, 10 are respectively held between the inner peripheral surface 3 a and the inner and outer engagement grooves 7, 8.
And six balls 4, 4, which are free to roll along the inner and outer engagement grooves 7, 8 while being held inside the pockets 10, 10. doing. Then, each of the balls 4, 4 is connected to the one shaft 5 and the other shaft 6.
Are arranged in the bisecting plane c of the axis intersection angle θ with the axis.

Further, in the zepper type constant velocity joint of the present invention, as shown in FIG.
A step portion 12 corresponding to the step-like portion described in the claims is formed at a portion slightly closer to the inner peripheral surface (lower portion in FIG. 1) than the middle position in the inward and outward directions (vertical direction in FIG. 1) with respect to the diametrical direction. ing. In the case of this example, the step 12 is provided only on one (left side in FIG. 1) of the pair of inner surfaces located on the opposite side of the pocket 10 in the axial direction. The inclination angle of the step portion 12 is different from the inclination angle of the portion other than the step portion 12, and the width of the pocket 10 in the axial direction (the left-right direction in FIG. 1) is determined based on the presence of the step portion 12. Is smaller at a portion closer to the inner peripheral surface of the retainer 9 and is larger at a portion closer to the outer peripheral surface. The width W _{1 of the} portion close to the inner peripheral surface is set to be equal to or slightly smaller than the outer diameter D of the ball 4 (W ₁ ≦
D), width dimension W _{2 of the} intermediate position in the inward and outward directions and the portion near the outer periphery
Is larger than the outer diameter D of the ball 4 (W ₂ > D).

The thus configured Zepper constant velocity joint of the present invention transmits rotational motion from the inner ring 2 rotating to the outer ring 3 based on the driving force transmitted from the transmission. The other shaft 6 fixed to the part
The effect of rotating the drive wheels by the above is the same as in the case of the conventional Zeppa constant velocity joint described above.

In particular, in the case of the Zeppa type constant velocity joint of the present invention, the ball 4 can be used even if the joint angle of the Zeppa type constant velocity joint is increased with the addition of the steering angle to the front wheel which is the driving wheel. 4 does not violently collide with the inner surfaces of the pockets 10 and 10 to generate a tapping sound. That is, according to the experiment performed by the present inventors, as shown in FIG.
When a large joint angle is given to the Zeppa constant velocity joint and the inner ring 2 is rotated by increasing the difference (WD) between the width dimension W of the pocket 10 and the outer diameter dimension D of the ball 4, Balls 4, 4 arranged at equal intervals in the circumferential direction
Among them, it was found that only the balls 4 and 4 existing within a certain angle range generate a hitting sound.

In the experiment, of the six pockets 10 and 10 formed in the retainer 9, only the width W of one pocket is larger than the outer diameter D of the ball 4 (W> D). , The width dimension W of the remaining five pockets 10 is the outer diameter dimension D of the balls 4, 4.
(W = D), and the inner ring 2 was rotated through one shaft 5 with the joint angle increased as shown in FIG. According to this experiment, as shown in FIG. 8, ± 30 degrees around the bending direction of the other axis 6 with respect to the one axis 5, and a total of 60 degrees
It has been found that a hitting sound is generated when the ball 4 held in the pocket 10 having the large width W is present.

By the way, in the Zeppa type constant velocity joint which is the object of the present invention, each ball 4, 4 is positioned within the bisecting plane c of the axis intersection angle between the one shaft 5 and the other shaft 6. As described above, the point d, which is the center of curvature of the bottom surfaces 7a, 7a of the inner engagement grooves 7, 7, and the bottom surfaces 8a,
The point e, which is the center of curvature of 8a, is shifted. Because of this,
The balls 4, 4 positioned in the bending direction of the one shaft 5 with respect to the other shaft 6 approach the intersection o between the center line a of the one shaft 5 and the center line b of the other shaft 6 and move away from the bending direction. The farther away from this intersection o. Therefore, in the Zeppa constant velocity joint of the present invention, the balls 4, which are likely to produce a hitting sound, are within the range of 60 degrees shown in FIG. It is displaced to a portion closer to the peripheral surface (a lower portion in FIG. 1), and is located in a portion of the pocket 10 having a small width. As a result, even when the joint angle is increased, the ball 4 does not collide with the inner side surface of the pocket 10, and unpleasant hitting sound is not generated.

The remaining balls 4, 4 at positions where it is difficult to produce a hitting sound are provided with the inner engaging grooves 7, 7 and the outer engaging grooves 8, 8, respectively.
In each of the pockets 10, 10, the cage 9
Are displaced from the inward / outward intermediate portion toward the outer peripheral surface (upper portion in FIG. 1), and are located in the wide portions in the pockets 10, 10. Therefore, vibration is not easily transmitted between the inner ring 2 and the outer ring 3. In particular, in a state where the steering angle is not applied to the front wheels, that is, in a state where the joint angle of the Zeppa constant velocity joint 1 is small, all the balls 4, 4
Is located in the middle portion of the cage 9 in the inside and outside directions in the pockets 10 and 10 where the width dimension is widened. Thus, transmission of vibration between the inner ring 2 and the outer ring 3 can be effectively prevented.

FIG. 2 shows a second embodiment of the present invention. Since the first embodiment changes the width dimension of the pocket 10 between the inner peripheral side and the outer peripheral side, one of the pair of inner side surfaces located on the opposite side in the axial direction of each pocket 10 has an intermediate portion on one inner side surface. In the present embodiment, the step portions 12 and 12 each having a step-like portion are formed in the middle portion of both inner side surfaces. Other configurations and operations are the same as those of the first embodiment.

FIG. 3 shows a third embodiment of the present invention. In each of the first and second embodiments, the pocket 1
In contrast to the case where the width of the inner peripheral side of the pocket 0 is narrow and the width of the intermediate part and the outer peripheral side is wide, in the case of this embodiment, the pocket 1
Of the pair of inner surfaces located on the opposite side in the axial direction of 0, a recess 13 is formed in the inner portion in the inward / outward direction of one of the inner surfaces, so that the width of the inward / outward intermediate portion of each pocket 10 is increased. . In the case of this example, of both edges of the concave portion 13, the edge on the inner side in the diameter direction of the retainer 9 (the lower side in FIG. 3) corresponds to a step portion described in claims. In the case of the present embodiment configured as described above, in a state where the steering angle is not given to the front wheels, the diameter of the plurality of balls 4 (FIG. 1) constituting the Zeppa constant velocity joint is the largest. The part that became
All of the pockets 10 are located at intermediate portions in the inward and outward directions, and face the recesses 13 respectively. Therefore, the vibration of the engine during idling is not easily transmitted from the inner wheel 2 to the outer wheel 3. Other configurations and operations are the same as those in the first and second embodiments.

FIG. 4 shows a fourth embodiment of the present invention. In contrast to the above-described third embodiment in which the recess 13 is formed only at the intermediate portion of one of the inner surfaces of the pair of inner surfaces located on the opposite side in the axial direction of the pocket 10, this embodiment In the case of the example, the recess 1
3 and 13 are formed. Other configurations and operations are the same as those of the third embodiment.

[0023]

[Effect of the invention] The Zeppa type constant velocity joint of the invention is
The structure and operation described above can prevent the transmission of engine vibration, prevent the occurrence of tapping noise when the joint angle is large, and effectively prevent the occupant from feeling uncomfortable. .

[Brief description of the drawings]

FIG. 1 is a view showing a first embodiment of the present invention and corresponding to a cross section taken along line AA of FIG. 7;

FIG. 2 is a sectional view similar to FIG. 1, showing the second embodiment;

FIG. 3 is a sectional view similar to FIG. 1, showing the third embodiment;

FIG. 4 is a sectional view similar to FIG. 1, showing the fourth embodiment;

FIG. 5 is a cross-sectional view showing a Zeppa type constant velocity joint to which the present invention is applied.

FIG. 6 is a view showing a state in which the joint angle is set to zero, and FIG.
Sectional drawing seen in the line direction.

FIG. 7 is a view as viewed from above in FIG. 6 with the outer ring omitted;

FIG. 8 is a view of the ball viewed from the direction of arrow C in FIG. 5 to show the relationship between the position of the ball and occurrence of a hitting sound.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Zeppa type constant velocity joint 2 Inner ring 2a Outer peripheral surface 3 Outer ring 3a Inner peripheral surface 4 Ball 5 One shaft 6 The other shaft 7 Inner engaging groove 7a Bottom surface 8 Outer engaging groove 8a Bottom surface 9 Cage 10 Pocket 12 Step 13 Recess

──────────────────────────────────────────────────続 き Continued on the front page (56) References JP-A-61-160628 (JP, A) JP-A-61-28919 (JP, U) JP-A-2-417 (JP, U) JP-A-62 6532 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) F16D 3/20-3/24

Claims (1)

(57) [Scope of request for utility model registration] 1. An inner ring fixed to an end of one shaft, and formed at equal circumferential positions on the outer peripheral surface of the inner ring at integer multiples of 3 and at right angles to the circumferential direction. an inner engagement grooves of circular arc cross sectional shape that is, an outer ring fixed to an end portion of the other shaft, the inner peripheral surface of the outer ring, in a position facing the inner engagement grooves, with respect to the circumferential direction An outer engaging groove formed in a right angle direction and having an arc-shaped cross section, and a pocket which is sandwiched between an outer peripheral surface of the inner ring and an inner peripheral surface of the outer ring and is positioned at a position matching the inner and outer engaging grooves. And a plurality of balls of an integral multiple of 3, which are rotatable along both the inner and outer engagement grooves while being held inside each pocket. In a Zeppa type constant velocity joint arranged in a bisecting plane of an axis intersection angle between one axis and the other axis,
A pair of inner surfaces facing axially opposite the cage;
That is, at least the middle part of one of the inner surfaces
By providing a step-shaped part with a different inclination angle from the outside part
The width dimension of each pocket in the axial direction of the retainer is
A cepper-type constant velocity joint, wherein the outer diameter of the ball is smaller than or equal to the outer diameter of the ball at a portion near the inner peripheral surface of the retainer, and is larger than the outer diameter of the ball at least at an intermediate position in the inner and outer directions.