Tripode joint with roller bearing

Details Tripode joint with roller bearing Tripode joint with roller bearing

1999-03-24

2001-05-08

Browne, Lynne H. (Department: 3629)

Rotary shafts, gudgeons, housings, and flexible couplings for ro

Coupling accommodates drive between members having...

Tripod coupling

C464S905000, C464S132000, C464S128000

Reexamination Certificate

active

06227978

ABSTRACT:

BACKGROUND OF THE INVENTION
The invention relates to a constant velocity tripode joint having an outer joint part with an inner aperture and three uniformly circumferentially distributed recesses which widen the inner aperture. Each recess includes two opposed tracks. The tripode joint also has an inner joint part with a center piece having three uniformly circumferentially distributed tripode arms that are arranged radially relative to the center piece and that each extend into one of the recesses. The tripode joint further includes roller assemblies each of which is rotatably supported on one of the tripode arms and that are in rolling contact with the tracks of their respective recesses.
Tripode joints of this type serve to transmit torque between the inner joint part and the outer joint part and are used especially in the drivelines of motor vehicles. When the joint rotates and when the longitudinal axes of the inner joint part and of the outer joint part are articulated relative to one another, the roller assemblies, in their respective recess, periodically move longitudinally to and fro. In tripode joints wherein the roller assemblies are held coaxially on the tripode arms, the roller assemblies carry out periodic angular movements that are superimposed on the longitudinal movements and their angle is twice the size of the angle of articulation between the longitudinal axes. To the extent that the roller assemblies are held angularly movably on the tripode arms, the longitudinal to- and fro- movements take place with the roller axes of the roller assembly extending parallel relative to one another.
During the transmission of torque, the roller assemblies each rest against one of the tracks of the recesses in a coinciding circumferential direction, whereas there necessarily exists a gap between the roller assembly and the other one of the tracks of the respective recess. There exist some restrictive effects because the edges of the second track are alternately contacted by outer annular edges of the roller assemblies. When the tripode joint rotates in a torque-free way, such as is the case when a vehicle changes from operating under load to a pushing operation or when it is operated in a substantially load-free condition, the contact of the roller assemblies changes between the two tracks of each of the recesses. The change in contact is associated with noise generating pulses and the noise adversely affects driving comfort.
It is therefore the object of the present invention to develop a constant velocity tripode joint of the above-mentioned type in such a way that the noise generated by the change in contact of the roller assemblies between the tracks of the recesses during torque-free operation is reduced.
SUMMARY OF THE INVENTION
The objective is achieved by designing each roller assembly to comprise at least two rollers that are independently rotatable relative to their respective tripode arm and that are at least indirectly supported on the tripode arm in the radial direction relative to the axis of the arm. A roller assembly includes a first roller that rolls on the first of the two tracks of its recess and is rotatable with a gap between it and the second track. The roller assembly further includes a second roller that rolls on the second of the two tracks of its recess and is rotatable with a gap between it and the first track.
As a result of the geometric arrangement, a roller assembly can be designed so that it is inserted almost without play between the track contact with the first track and the track contact with the second track, and at the same time, because of the free rotatability of the two rollers relative to one another, rolling movements take place at both tracks, should any contact occur at the same time. Because of the very small amount of designed play, any noise pulse resulting from a change in contact from one track to the other track due to a change in torque is avoided almost completely. The independent rotatability of the two rollers of each roller assembly avoids an increase in the sliding friction percentage at the respective unloaded track because, when contact occurs, the respective roller is able to roll freely in the right sense.
According to a preferred embodiment in each roller assembly, a first roller is supported by a first needle bearing on its respective tripode arm and a second roller is supported by a second needle bearing on the first roller. In such an embodiment, the roller assemblies are held coaxially relative to their respective tripode arm, while they are movable on the first needle bearings in the direction of the arm axis. When the rotating tripode joint is at an angular position, the axial rolling movements of the roller assemblies are superimposed by pivot movements within the recesses, and care has to be taken to ensure that the width of a longitudinal groove in the first track is great enough to accommodate a pivot movement of the second roller within the longitudinal groove without there occurring any edge contacts.
According to a second embodiment in each roller assembly, a first roller is pivotably held on a spherical sleeve that is supported on the tripode arm by a first needle bearing and a second roller is supported on the first roller by a second needle bearing. In this embodiment, the roller assemblies of the tripode joint rotating in an angular position are guided in a form-fitting way within the recesses, with the axes of rotation being held so as to extend parallel relative to one another. The longitudinal groove within the first track can be adapted relatively closely to the width of the second rollers without functioning being adversely affected. The width of the running faces in the recess are increased accordingly.
According to a third embodiment in each roller assembly, a first roller is rotatably supported by a first needle bearing on a sleeve which, in turn, is pivotably guided on a spherical tripode arm and a second roller is supported on the first roller by a second needle bearing. The functioning of such a tripode joint substantially corresponds to the latter tripode joint functioning described above. Instead of a rotatably supported spherical sleeve which is pivotable relative to the first roller, there is provided an intermediate sleeve which is pivotable relative to the tripode arm and on which the first roller is rotatable.
According to a further preferred embodiment, the first roller is composed of two parts that form a central annular groove for a respective second needle bearing and a second roller. This design permits the second needle bearing and the second roller to be assembled without the need for a plurality of securing elements. When using spherical sleeves to achieve pivotability of the roller assemblies on the tripode arms, the spherical sleeves can also be assembled quite easily with the first rollers. According to a further advantageous embodiment the running face of the second roller projects beyond the running face of the first roller and in the respective first tracks there is provided a longitudinal groove to allow the respective second roller contact-free engagement relative to the running face. In each position of contact of the roller assemblies on one of the two tracks of each recess one of the rollers of the roller assembly is loaded substantially symmetrically and it may be advantageous for the size conditions to be such that in a preferred direction of torque transmission the contacting rollers are subjected to a reduced specific load.
Preferably, the running face of the first roller and the running face of the second roller, relative to one another, form concentric spherical surfaces of different diameters. This is a preferred embodiment especially when the roller assemblies are held so as to extend coaxially relative to the axes of the tripode arms. If the roller axes are pivotable relative to the tripode arm axes, different shapes of running faces, especially entirely cylindrical shapes of the first and second rollers can be used.
In a further embodiment each roll

Affiliated with

Also associated with

Rating

Tripode joint with roller bearing does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Tripode joint with roller bearing, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Tripode joint with roller bearing will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2566851