Joint assembly

Abstract

Oppositely facing surfaces have grooves in one of the surfaces and low coefficient of friction inserts in the grooves. The inserts have a thickness greater than the depth of the grooves so as to project from the grooves when seated therein for bearing against a facing surface and maintaining the two surfaces in spaced apart relation. Such inserts provide a reduced friction relation between the two surfaces whereby the two surfaces can be readily rotated between a working condition having a thrust load therebetween and a loosened non-working condition. Preferably, two or more of the grooves and inserts are provided, the inserts being held in the grooves by distorted portions in the walls of the grooves. The joint assembly of the invention is particularly applicable to rock crushers of the type having a threaded connecting joint between a bowl member and support therefor, whereby the low coefficient of friction inserts provide a liner or spacer which prevents galling of the threads under heavy load and provides for ready rotation of the two members when desired. The present joint assembly may also be used in association with the threads of a jam nut of a type which locks the bowl against rotation on the support, and furthermore may be used in unthreaded opposing surfaces between the jam nut and the support.