Hydraulic device for operating a clutch in an industrial vehicle.

摘要

A hydraulic device for operating a clutch in an industrial vehicle having a transmission comprising shift changeable gears and manually operated shift levers. Gear actuating hydraulic boosters are provided for hydraulically actuating the shift changeable gears, and the clutch is actuated by a clutch cylinder. The hydraulic device comprises a clutch circuit extending between a hydraulic pump and the clutch cylinder, and a booster circuit extending between the hydraulic pump and the boosters. A gate valve is arranged in the clutch circuit and is movable in response to a pressure of a hydraulic oil in the booster circuit, so that the normally closed gate valve is opened when the manually operable shift levers are operated. Also, a pressure control circuit is branched from the clutch circuit and again branched into parallel third and fourth hydraulic circuits. A forward and reverse gate valve and a speed change gate valve are arranged in the third and fourth hydraulic circuits, respectively. A check valve and a first accumulator are arranged in the third hydraulic circuit and a second accumulator is arranged in the second hydraulic circuit upstream of the second gate valve for controlling a rise of a pressure applied to the clutch cylinder.