HYDRAULIC COUPLING FOR AUXILIARY DRIVE AXLE OF A VEHICLE DRIVETRAIN

摘要

A hydraulic coupling (38) for coupling a casing (46) and a pair of axle half shafts (40) of an auxiliary drive axle (36) of a vehicle drivetrain (22) includes a housing (44) for containing hydraulic fluid and the casing (44) rotatively mounted within the housing. A clutch (76) extends between the casing (46) and each of the axle half shafts (40) and is actuable to transfer torque therebetween by the operation of a pair of hydraulic pumps (90) that provide pumped hydraulic fluid to a pair of piston chambers (110) whose pistons (120) actuate the clutch. An outlet port (122) of each piston chamber (110) and an associated temperature compensated valve (124) and a pressure relief valve (126) of each piston chamber control the clutch actuation.