Patent ID: 7111862
Filing Date: 2006-09-26
Classification: B60G,B62D

Abstract:
1. A modular suspension system adapted to a terminal tractor having a frame, comprises: lift arm assembly having a front segment and a rear segment pivotally attached to a fifth wheel plate; and a trailing arm assembly having a front segment and a rear segment attaching to a rear axle, said front segment of said trailing arm assembly pivotally connecting to said frame of said terminal tractor at two pivot bushing socket tubes housing elastomeric trailing arm pivot bushings which rotate on a common axis, said elastomeric trailing arm bushings holding an enforced longitudinal position of said trailing arm assembly while allowing limited vertical movement and side-to-side rotation of said trailing arm assembly relative to said frame, wherein said front segment of said lift arm assembly is joined to said trailing arm assembly by two large diameter composite bushings rotating on said outer surfaces of said pivot bushing socket tubes of said elastomeric trailing arm pivot bushings, said elastomeric trailing arm pivot bushings isolating said trailing arm assembly and said lift arm assembly from said frame, with at least one lift cylinder forcing said lift arm assembly from said trailing arm assembly to forcibly elevate and lower said lift arm assembly and said fifth wheel plate.