Hydraulikkreis zur Betätigung von Lastschaltkupplungen für Zugmaschinengetriebe

摘要

A hydraulic circuit for operating clutches which have respective hydraulic actuators (2) connected to supply and exhaust means through respective valve units (1a-3b) operated by electronically-controlled piloting means for engaging and disengaging the clutches in combination in order to change gear ratios without interrupting the transmission of torque. The supply and exhaust means include a single hydraulic pump (3) connected by a first delivery line (7) to electronically-controlled on-off valves (18) through an electronically-controlled proportional pressure-reduction valve (20) and respective one-way valves (21), the pump (3) being connected directly by a second delivery line (8) to sequence valves (15) piloted by the pressures in the respective actuators, and an exhaust line (19) connected directly to the electronically-controlled on-off valves (18).