Hydromechanical system for limiting differential speed between differentially rotating members

摘要

A hydromechanical system for limiting differentiation between a first rotating member and a second rotating member in a drivetrain subassembly. The hydromechanical system comprises a clutch assembly for selectively coupling the first rotating member to rotate with the second rotating member and a hydraulically actuated piston assembly for applying force on the clutch assembly to actuate the clutch assembly in response to hydraulic pressure such that the first rotatable member is selectively coupled to rotate with the second rotatable member. A clutch actuating pump, including a reservoir, is provided for supplying hydraulic pressure to the piston assembly to actuate the piston assembly, wherein the clutch actuating pump communicates hydraulic fluid under pressure to the piston assembly in response to differential rotation between the first and second rotating members. A second pump is also provided in fluid communication with the reservoir of the clutch actuating pump for supplying hydraulic fluid to the reservoir of the clutch actuating pump. The hydromechanical system is well suited for use in a four-wheel drive transfer case to control differentiation between the front and rear output shafts thereof.