An electric powered pneumatic balancer is provided. In an embodiment it includes: a housing; an air balancer located in the housing; and a compressor located in the housing. The housing includes an opening to receive air to the compressor as it generates compressed air. The compressor is in fluid communication with the balancer which operates in response to receipt of the pressurized air from the compressor. An electrical power supply is in electrical communication with the compressor to power the compressor to generate the pressurized air.

An electric powered pneumatic balancer is provided. In an embodiment it includes: a housing; an air balancer located in the housing; and a compressor located in the housing. The housing includes an opening to receive air to the compressor as it generates compressed air. The compressor is in fluid communication with the balancer which operates in response to receipt of the pressurized air from the compressor. An electrical power supply is in electrical communication with the compressor to power the compressor to generate the pressurized air.

The present invention is provided with: a manipulation unit; a winch device that operates with an actuation mode of either a high speed mode or a low speed mode, and winds in or reels out a wire rope; a selection unit for an operator to select either the high speed mode or the low speed mode; a load calculation unit calculating a suspended load; a tension calculation unit calculating the tension of the wire rope; and a control unit controlling the actuation of the winch device. If the mode selected by the selection unit is the high speed mode, the manipulation unit is manipulated from a neutral state to a non-neutral state, and the suspended load is smaller than a load threshold and the tension is smaller than a tension threshold, the control unit controls the winch device so as to operate in the high speed mode.

A hydraulic system may include a reservoir of hydraulic fluid, a hydraulic pump, a directional control valve, a hydraulic work loop, a bypass valve, and a hydraulic motor, as well as a plurality of hydraulic conduits interconnecting such components. When excessive hydraulic backpressures are encountered, the system may employ one or more bypass valves and one or more bypass conduits to automatically, and in an on-demand manner, return some or all of the hydraulic fluid from the hydraulic motor to the hydraulic reservoir without the hydraulic fluid passing through flow constrictions causing the excessive hydraulic backpressures.

There is provided a crane winch device allowing a suspended load to freely fall due to a load thereof. The crane winch device includes a winch drum around which a rope for suspending the suspended load is wound, braking brake unit that brakes the winch drum, speed-increasing unit that performs speed-increasing assist of the winch drum in a direction of free fall acceleration when a braking force of the brake unit is smaller than a first threshold, and an adjustment unit that adjusts the first threshold.

There is provided a crane winch device allowing a suspended load to freely fall due to a load thereof. The crane winch device includes a winch drum around which a rope for suspending the suspended load is wound, braking brake unit that brakes the winch drum, speed-increasing unit that performs speed-increasing assist of the winch drum in a direction of free fall acceleration when a braking force of the brake unit is smaller than a first threshold, and an adjustment unit that adjusts the first threshold.

A control device of a hydraulic winch includes an engine, a hydraulic pump, a hydraulic motor driving a winch drum, a winch manipulating member, an engine control unit controlling a rotation speed of the engine, a winch load detector detecting a load applied to the winch drum, and a motor capacity control unit controlling a motor capacity of the hydraulic motor so as to decrease a motor capacity of the hydraulic motor in a fuel-saving operation mode to a motor capacity which is smaller than a motor capacity of the hydraulic motor in a normal operation mode. The engine control unit sets an upper limit value of the rotation speed of the engine in the fuel-saving operation mode to a value which is lower than a maximum rotation speed of the engine in the normal operation mode and corresponds to the load detected by the winch load detector.

A control device of a hydraulic winch includes an engine, a hydraulic pump, a hydraulic motor driving a winch drum, a winch manipulating member, an engine control unit controlling a rotation speed of the engine, a winch load detector detecting a load applied to the winch drum, and a motor capacity control unit controlling a motor capacity of the hydraulic motor so as to decrease a motor capacity of the hydraulic motor in a fuel-saving operation mode to a motor capacity which is smaller than a motor capacity of the hydraulic motor in a normal operation mode. The engine control unit sets an upper limit value of the rotation speed of the engine in the fuel-saving operation mode to a value which is lower than a maximum rotation speed of the engine in the normal operation mode and corresponds to the load detected by the winch load detector.

The present disclosure relates to a hydraulic system including a variable displacement hydraulic motor for lifting and lowering a load. The hydraulic motor has a high operating speed and a low operating speed. The system also includes an actuator for controlling whether the hydraulic motor is operating at the high or low speed, and a pressure sensor for sensing when a system pressure corresponding to the hydraulic motor exceeds a threshold pressure value. The system further includes a speed control system that controls the actuator such that the hydraulic motor is prevented from operating at the first operating speed when the system pressure exceeds the threshold pressure value.

The present disclosure relates to a hydraulic system including a variable displacement hydraulic motor for lifting and lowering a load. The hydraulic motor has a high operating speed and a low operating speed. The system also includes an actuator for controlling whether the hydraulic motor is operating at the high or low speed, and a pressure sensor for sensing when a system pressure corresponding to the hydraulic motor exceeds a threshold pressure value. The system further includes a speed control system that controls the actuator such that the hydraulic motor is prevented from operating at the first operating speed when the system pressure exceeds the threshold pressure value.