Bushing

Abstract

A bushing having particularly advantageous use with heavy duty truck suspensions and including: i) a first outer bushing member; ii) a second inner bushing member defining an annular space between the first and second bushing members; and iii), an elastomeric interface disposed within the annular space between the first and second bushing members in face-to-face contact with; first and second sets of grooves formed in one of the first and second bushing members with the first set of grooves being axially spaced from the second set of grooves by a greater axial distance on one side of the grooved member than the axial spacing on the diametrically opposite side of the grooved member. In the exemplary bushings, first and second sets of grooves are formed on the inner surface of the first bushing member. The first and second sets of grooves may comprise helical threads of different hand, helical threads of different pitch, or discrete axially spaced grooves which may, but need not, be discrete continuous endless grooves. The inner and outer bushing members may be metal, or they may be a composite material including filament wound glass fibers and an epoxy resin, or the outer bushing member may be a composite material including filament wound glass fibers and an epoxy resin while the inner bushing member is metal. The inner bushing member may also be a compression molded composite material including glass fibers embedded in an epoxy resin. The elastomeric interface material is preferably urethane.