JPH0118295B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention comprises a tulip-shaped yoke, which is attached to the inner end of the yoke so as to be movable and pivotable in the radial direction, and which is attached to the inner end by an elastic clip. The present invention relates to a tripod type constant velocity rotary joint that includes a tripod member that is maintained in a preloaded state. Said clip has a branch, the free end of which is fixed to the petal part of the yoke. These constant velocity rotary joints have conventionally been used in steering systems and driving the front wheels of front-wheel drive vehicles.

The alternating force generated by the drive unit,
In order to avoid axial movement of the yoke relative to the tripod member due to road conditions, various frictions, and the actuation of the angular joint under torque, etc., the clip eliminates the axial play of the components and Despite the tolerances due to the machining of the components and the wear and tear that occurs as a result of long-term use of the joints, and without creating axial flexibility between the tripod member and the yoke,
It is known that there is a need to provide a permanent preload of a constant value to bring the central portion of the tripod member into contact with the inner end of the yoke.

Furthermore, in order to obtain this preload, it must not create substantial resistance to correct actuation of the joint that would impair a smooth joint. The clip is further required to withstand abnormally high axial forces without loss of function.

In order to satisfy all of these requirements, it has been proposed to complete the clip with various play removal devices. However, conventional devices, such as the one disclosed in French Patent No. 7726873,
There are considerable drawbacks in terms of mass production. increased number of components incorporated into constant velocity rotary joints, need for special adjustment and inspection of each component, increased assembly and inspection time and cost and risk of error, reduced force and cost of tripod members. In order to install a play removal device, which leads to an increase in the number of joints, it is necessary to complicate and modify the structure of one of the main components of the joint, namely the tripod member.

The object of the invention is an axially retained joint in which the clip itself interposes an additional elastic damping member between the two main components of the joint in a simple and inexpensive manner. It is an object of the present invention to provide a joint which satisfactorily fulfills the function of a play removal device and ensures an axial preload on the inner end of the yoke of the central part of the tripod member, without causing any problems.

Accordingly, the present invention provides a constant velocity rotating joint of the type described above, in which, when the joint is in the open position, the branches of the clip are curved to move radially along the corresponding flange portion of the yoke. They are arranged with a play, which allows for high axial flexibility for axial forces weaker than a predetermined value, and lower axial flexibility for axial forces greater than a predetermined value. The present invention provides a joint in which a branch and a petal part are brought into contact with each other.

To make the assembly of the joint particularly convenient, it is preferable to arrange each fixing point in the inner end region of the run of the yoke. When assembling the fitting, it is very convenient to use the following tools: i.e. a tool with a lever, the distal end of which, on the one hand, has two projections for abutment with the tip of the run of the yoke, and on the other hand grips the free end of the branch of the clip. It is equipped with the means.

Other features and advantages of the invention will become apparent from the following description, given by way of example only and with reference to the accompanying drawings, in which: FIG.

The constant velocity rotary joint 1 shown in FIG.
is connected to a stub axle 3 of a front wheel of a front wheel drive vehicle. The joint comprises a tulip-shaped yoke 4 fixed to an axle 2 and a cup member 5 fixed to a stub axle 3. The tripod member 6 of the coupling is a spider with three radial trunnions 8;
A fixed ball 7 is formed at the tip of the trunnion 8, and the rear end of the trunnion is fixed to the inlet portion of the cup member 5. Each trunnion 8 has a spherical roller 9 rotatably and slidably mounted thereon. The roller 9 is housed in the tube yoke 4 in a running path 10 that has a circular shape in part and extends parallel to the axis of the yoke 4 in the other part. Each track 10 comprises two opposing tracks formed by machining on the edges of two of the three flange portions 11 of the yoke 4, the ferrule portions 11 of which It is approximately parallel to the axis XX and extends in a direction away from the transmission shaft 2.

This joint further includes an elastic clip 1 fixed to the yoke 4 to hold the tripod member 6 in the axial direction.
2, and on the other hand, around the inlet side of the cup member 5,
On the other hand, the shaft 2 is provided with boots 13 which are respectively fixed in a sealing manner.

The elastic clip 12 is made in a single piece from a flexible elastic metal plate, such as spring steel. When viewed from the joint as a whole, it is considered to have three-dimensional symmetry about the longitudinal axis XX of the joint and to be in a completely concentric state. It is a central concave part 1 that is embossed into a pot shape.
4, from the periphery of which extend three elastic and flexible very long branches 15.

The recess 14 has a flat inner end 1 that contacts the ball 7 and presses the ball against the flat inner end 17 of the yoke 4.
It has 6. Both inner ends 16, 17 are perpendicular to axis X--X. The lateral wall of this recess 14 comprises three branching sections 18 connecting the inner end 16 to the root of the branch 15 and, between the branching sections 18, three axial sections 19.

The outline of the branch 15 is swollen and vertically elongated. The base is regulated in the circumferential direction by a recess 20 formed on the outer surface of the free end of the petal 11, but does not contact the inner end of the recess 20. The branches 15 then extend into the cavity 21 along the outer surface of the floret 11 with a small radial recess and the large free end portion 2 of the branch 15
2 is telescopically arranged within the gap. This free end portion 22 constitutes the anchoring point of the branch.
The void 21 is located near the base of the floret 11, where the floret 11 becomes thinner and whose surface 23 is provided with an axial member facing the axis 2 (FIG. 3). and Figure 4).

The axial flexibility of the clip 12 is shown in FIG.
As the axial force F increases, the curvature of the branch 15 decreases until it contacts the outer surface of the floret 11. Above this point, the branch 15 is effectively only subjected to tensile stresses, said forces being transmitted to the branch 15 via the axial portion 19 of the recess 14, with the result that the clip 12 becomes very stiff and subject to considerable forces. become bearable.

Because of these characteristics, it is very easy to satisfy the following two conditions. That is, when the joints are in the open condition, radial play is maintained between the branch 15 and the flower flange 11 to account for preload changes from one joint to the other, regardless of manufacturing tolerances. and to withstand high axial forces without the clip 12 breaking or separating from the yoke 4.

This is done by reducing the overall dimensions of the clip 12 to a point small enough to allow the joint to be operated at the desired large angle, at no expense, easy to manufacture, and with a high degree of reliability. achieved. As a numerical example, for an average sized joint, the axial flexibility of the clip 12 is approximately 1.5 mm for a force of approximately 150 kg, while the axial preload is in the range of 60 to 150 kg. For forces above approximately 200 Kg, the branch 15 will be in contact with the outer surface of the yoke 4, and the clip will be able to withstand forces on the order of 1500 Kg without fear of breakage due to the expected abnormal axial forces. Can be done.

Assembly of the coupling becomes particularly easy. protective boots 13
, the end 22 of the branch 15 extends out of the cup member 5. In particular, the tools shown in FIGS. 3 and 4 can be used. This tool comprises a lever 25, the terminal end 26 of which is slightly upwardly curved and enlarged, and on its underside is mounted a cylindrical pin 27 arranged approximately in a transverse line.

To assemble the joint, the clip 12 is placed directly into the cup member 5 and the yoke 4 is inserted into the cup member 5. At this time, the branch 15 is guided by the recess 20 and reaches the vicinity of the gap 21. In order to obtain the desired preload, it is necessary to apply an axial force of 60/3=20Kg to 150/3=50Kg to each of them.

Therefore, the two end pins 27 of the tool 25 are in contact with the surface 23 of the flower tray 11, and the center pin 27
is locked in a through hole 28 provided in the enlarged portion 22 of the corresponding branch 15. Simply by rotating the lever 25 towards the axis 2, ie in the direction of the arrow f in FIG. 3, the free end part 22 is fitted into the cavity 21 formed for it. This operation, other 2
Repeat for each branch 15.

As a variant, it is also possible to install the three branches 15 more quickly and simultaneously using more sophisticated tools (not shown), such as hydraulic actuation, which is preferred for mass-produced automated assembly of joints.

Similar branches 15 can also be employed in other types of clips for the purpose of axially holding the tripod member 6 under preload, with the same effect. Some of these clips are shown in FIGS. 5-10.

The joints 1a to 1d shown in FIGS. 5 to 10 are meniscus type. The center of the tripod member 6a has two opposing planes perpendicular to the axis X--X, each of which is in contact with the plane of the meniscus dome 7a. One meniscus engages and pivots over an adjacent spherical surface 17a on the inner end of yoke 4, and the other meniscus pivots over spherical surface 16a of clip 12a. .

In the case of the joint 1a shown in FIG. 5, the surface 16a is
The clip 12a (FIGS. 6 and 7) is made of a very inexpensive steel plate pressed into one piece, and is formed entirely of the edges of three axial webs 29 having partially circular contours. Each web 29 has a clip 12a
2, passing through the edge of the triangular central part 30 on the flat surface of
Adjacent edges of the branches 15 are connected.
The outer edge of the web 29 is straight and the yoke 4
The clip 12a is centered in the center of the clip 12a with respect to the inner bore 4a of the clip 12a.

In the case of the joints 1b to 1d shown in FIGS. 8 to 10, the clip consists of two parts, namely three branches 15 and a central part, an elastically flexible part of bent sheet metal and a separate It has a concave spherical surface and is formed by its outer edge by a central bearing part which is self-centering in the peduncle 11, i.e. in the hole 4a.

In FIG. 8, the central portion 31b of the clip 32b is flat, and the central bearing portion 33b is a block of hardened steel or other material that smoothes the sliding of the adjacent meniscus 7a; It is in contact with a flat surface.

In FIG. 9, the central bearing portion 33c comprises a spherical web 34 and six axial webs 35, each axial web 35 extending from the central portion 32c of the clip 32c.
1c and its radially outer end only to obtain stability.

In the case of the joint shown in FIG. 10, each branch 15 of the clip 32d has an axial extension 36 extending into the corresponding floret 11, and the central portion 31d is hollow. The central bearing member 33d is a spherical web and is provided at its edge with an outer shoulder 37 that abuts the end of the extension 36 in the axial direction.

In each embodiment, the length of the clip branches can be shorter than shown.

[Brief explanation of drawings]

FIG. 1 is a partially longitudinal front view of the first embodiment of the present invention, FIG. 2 is a diagram showing changes in axial force due to axial deviation of the elastic clip, and FIGS. FIG. 5 is a partially longitudinal front view of the second embodiment of the present invention, and FIGS. 6 and 7 are front views of the clip assembled to the yoke of the present invention from different directions. Front and side views of the clip, No. 8
Figures 10 through 10 are partially vertical front views of third, fourth and fifth embodiments of the present invention. 1, 1a to 1d...Joint, 2...Transmission shaft, 3...
...Stub axle, 4...Tulip type yoke, 5
...Cup member, 6, 6a...Tripod member, 7...
Ball, 7a... Meniscus dome, 8... Trunnion, 9... Spherical roller, 10... Runway, 11
...Flower buds, 12, 12a, 32c, 32d...
...elastic clip, 14... recess, 15... branch, 16, 16a... inner end, 17, 17a...
Inner end, 18... Branch portion, 19... Axial portion, 20... Recess, 21... Gap, 22... Free end portion, 27... Pin, 28... Hole, 29... Web, 30, 31b, 31c...Central part, 33
c, 33d...Center swing bearing member, 34...Web, 35...Web, 36...Extension portion, 37...
Sjorda.

Claims (1)

[Scope of Claims] 1. A tube-shaped yoke, which abuts in a radially movable and pivotable manner against the inner end of the yoke, and is maintained in a preloaded state against the inner end by an elastic clip. a tripod-type constant velocity rotary joint, the elastic clip having a branch, the free end of the branch being fixed to the petal part of the yoke, the joint being open; When in this state, the branches of the clip are curved and extend along the corresponding petals of the yoke with a radial gap between them, which allows the branches to touch the petals. When abutting, high axial flexibility is provided in the case of an axial force that is weaker than a predetermined value, and low axial flexibility is provided in the case of an axial force that is stronger than the predetermined value. A constant velocity rotating joint featuring: 2 In the open state, the branch is in a swollen state, and the contact with the corresponding petal is as follows.
2. The constant velocity rotary joint according to claim 1, wherein the constant velocity rotary joint is adapted to be operated only at a point fixed to the flower petal. 3. The constant velocity rotary joint according to claim 1 or 2, wherein the clip includes an axial portion that transmits the axial force of the central portion of the tripod member to the branch. 4. Claim 1, wherein the clip is made in one piece and has a central, pot-shaped recess with an inner end abutting the central part of the tripod member.
Constant velocity rotary joint according to item 2 or 3. 5. Claims 1 and 2, wherein the clip is manufactured as a single piece and has an axial web in its central part that abuts the central part of the tripod member.
Constant velocity rotary joint according to item 3 or item 3. 6. Claim 1, wherein the clip is in contact with the central part of the tripod member by means of an attachment member.
3. Constant velocity rotary joint according to item 2, item 2, or item 3. 7. The constant velocity rotary joint according to any one of claims 1 to 6, wherein each fixing point is located in a region where the inner end of the travel path of the tripod member exists.