Patent ID: 6227340
Filing Date: 2001-05-08
Classification: F16D

Abstract:
A hydraulically operated device having coupling packs operatively connected with a single hydraulic piston for varying the torque transfer between two points in power transmission characterized by the coupling packs including first and second sets of friction components; a first spring interposed between the piston and the first set of friction components and a second spring interposed between the first set of friction components and said second set of friction components; said second spring having a greater spring force than said first spring and operative when said first set of friction components are engaged by said piston to overcome the force of said second spring whereby said first set of friction components are initially engaged and then said second set of friction components are engaged so as to provide a dual friction disc coupling gain and wherein the first friction disc coupling gain has a slope dependent upon the spring rate of the first spring and the second friction disc coupling gain has a slope dependent upon the spring rate of the second spring.