Control device for hydraulic winch; has variable capacity hydraulic motor supplied by hydraulic pump with control valve driven by winding up and down operation devices and unit to control free fall

摘要

The control device has a variable-capacity hydraulic motor (2) supplied by a hydraulic pump (6) to drive a winch drum (1). A control valve (5) controls the supply and drainage of oil to the hydraulic motor and is driven by winding up and down operation devices on winding up (4) and down (3) sides. A unit operates a hydraulic motor capacity control unit (12) in free fall, to adjust the motor to a small capacity and operate a lowering unit, to rotate the winch drum at high speed and effect free fall operation.