A universal joint includes a trunnion including an annular recess in an outer surface. A bearing cup is disposed on the trunnion and includes an inner diameter surface having a retention recess therein. A needle bearing assembly is disposed between an outer surface of the trunnion and the inner diameter surface of the bearing cup. A seal assembly is disposed at an open end of the bearing cup and includes a seal support insert including a radially outwardly protruding retention member engaged with the retention recess of the bearing cup. An elastomeric seal is molded to the seal support insert and includes a plurality of radially inwardly extending seal lips engaging the outer surface of the trunnion and a dust lip extending axially from the seal support insert and including a dust lip retention feature received in an annular recess of the trunnion.

FIELD

The present disclosure relates to a u-joint and more particularly to a seal for sealing between a trunnion and a bearing cap of a u-joint.

BACKGROUND AND SUMMARY

Universal joints are structures which are well known in the art. Such joints usually include a cross member having a central body portion with four trunnions extending outwardly therefrom. The trunnions extend at right angles relative to one another and lie in a single plane. A central bore is provided in each trunnion forming an opening in the end of the trunnion opposite the central body portion. A hollow cylindrical bearing cup, closed at one end, is disposed over the open end of each of the trunnions. Roller bearings are provided between each of the bearing cups and its associated trunnion such that the bearing cups are rotatably mounted thereon.

During assembly, lubricant can be placed in the central bore in each trunnion. During operation of the universal joint, centrifugal forces move the lubricant outwardly from the trunnion bore towards the closed ends of the bearing cups. The lubricant passes around the outer ends of the trunnions adjacent the closed ends of the bearing cups and radially inwardly back between the bearing cups and the trunnions where the roller bearings are disposed. In this manner, the roller bearings are lubricated for use.

It is known to provide the open ends of the bearing cups with elastomeric seals. The elastomeric seal is typically positioned between the trunnion and bearing cup to form a seal therebetween. To provide an effective seal, such seals must resist the entry of contaminants into the bearing cup and restrict the flow of lubricant out of the region of the bearing cup where the roller bearings are located. The assembly of the seal in proper alignment between bearing cup and the trunnion can be challenging.

Accordingly, the present disclosure provides a universal joint that includes a trunnion including an annular recess therein. A bearing cup is disposed on the trunnion and includes an inner diameter surface having a retention recess therein. A needle bearing assembly is disposed between an outer surface of the trunnion and the inner diameter surface of the bearing cup. A seal assembly is disposed at an open end of the bearing cup and includes a seal support insert including a radially outwardly protruding retention member engaged with the retention recess of the bearing cup. An elastomeric seal is engaged with the seal support insert and includes a plurality of radially inwardly extending seal lips engaging the outer surface of the trunnion and a dust lip extending axially from the seal support insert and including a dust lip retention feature received in an annular recess of the trunnion.

DETAILED DESCRIPTION

With reference toFIG. 1, a cross member10for a universal joint is shown in partial view including a trunnion12having a hollow central bore14. A roller bearing assembly16surrounds the trunnion12and is disposed inside of a bearing cup18. A universal joint seal20is provided between an open and22of the bearing cup18and the trunnion12.

With reference toFIG. 2, a detailed cross-sectional view of the interface region between the bearing cup18, trunnion12and universal joint seal20will now be described in detail. The interior surface of the bearing cup18includes an annular retention recess24therein. The seal20includes a seal support insert26and an elastomeric seal28molded thereto. The seal support insert26can include a cylindrical portion26a, an inwardly extending annular rim26band an outwardly extending annular rim26c. The cylindrical portion26aincludes one or more outwardly protruding retention members30that engage the annular retention recess24on the interior surface of the bearing cup18for securing the seal20in connection with the open end22of the bearing cup18. The elastomeric seal28can include a plurality of seal lips28a-28cthat extend radially inward therefrom. A dust lip34extends axially away from the seal support insert26and includes a dust lip retention feature36extending radially inward therefrom that is adapted to be in snap fit engagement with an annular recess38in an outer surface of the trunnion12.

During assembly of the cross member10, the seal20can be assembled to the bearing cup18prior to assembly on the trunnion12. Retention member30retains the seal member20within the open end22of the bearing cup18during handling of the bearing cup18and seal20. The seal20can also retain the roller bearing assembly16within the bearing cup18. Once the bearing cup18is inserted over top of the trunnion12, the dust lip retention feature36can be brought into snap fit engagement with the annular recess38in the outer surface of the trunnion12.