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 work vehicle includes: an operation tool that is operated by an operator; and a controller that determines a target flow rate for hydraulic oil fed to a hydraulic device on a basis of the amount of operation of the operation tool. The controller calculates a bleed-off target flow rate on a basis of the flow rate of hydraulic oil fed from a hydraulic oil pump and the target flow rate for hydraulic oil fed to the hydraulic device, calculates a bleed-off throttle differential pressure on a basis of a pressure of hydraulic oil fed from the hydraulic oil pump and a pressure of hydraulic oil in a hydraulic oil tank, calculates a bleed-off target opening area on a basis of the bleed-off target flow rate and the bleed-off throttle differential pressure, and controls a hydraulic oil control valve such that the bleed-off target opening area is achieved.

A work vehicle includes: an operation tool that is operated by an operator; and a controller that determines a target flow rate for hydraulic oil fed to a hydraulic device on a basis of the amount of operation of the operation tool. The controller calculates a bleed-off target flow rate on a basis of the flow rate of hydraulic oil fed from a hydraulic oil pump and the target flow rate for hydraulic oil fed to the hydraulic device, calculates a bleed-off throttle differential pressure on a basis of a pressure of hydraulic oil fed from the hydraulic oil pump and a pressure of hydraulic oil in a hydraulic oil tank, calculates a bleed-off target opening area on a basis of the bleed-off target flow rate and the bleed-off throttle differential pressure, and controls a hydraulic oil control valve such that the bleed-off target opening area is achieved.

A balanced lifting device comprises at least two lifting arms arranged opposite to each other, each lifting arm comprises a balance arm and an actuating arm driving the balance arm to move, the balance arm is rotatably connected to the actuating arm at a rotatably connected part, and a first drive device is arranged between the balance arm and the actuating arm to drive the balance arm to a horizontal state throughout the lifting process. A vehicle-mounted exchange box system and a multi-oil cylinder synchronization method are also provided in the present invention. A cargo box may be lifted stably to improve the operation safety, the vehicle utilization rate is improved by saving the waiting time for loading and unloading in the transfer process.

Provided is a crane (1) including: a boom (7); a wire rope (8); a winch (9); and a hook (10). The crane further includes: a spooling operation instrument (24) for enabling commanding an operation state of the winch (9); and switches (switch (41) or switch (42)) for enabling commanding a switch of a control mode with regard to the operation of the spooling operation instrument (24). When the boom (7) is in a flat travel orientation with the hook (10) loaded on a prescribed site (hook platform (12)), the switches ((41), (42)) being in an on state and the spooling operation instrument (24) being operated toward one side thereof cause the boom (7) to be raised to a work orientation while the wire rope (8) is unwound such that the hook (10) is not lifted.

A stabilised machine that comprises; a self-propelled base frame movably supported by a motorised ground support arrangement and provided with an upper support plane; a motorised turntable supported on top of the support plane of the base frame and rotatable with respect to an axis of rotation orthogonal to the support plane; an elevating arm, one first end of which is articulated to the turntable and one second opposed free end of which is adapted to be fixed to an operating arrangement; a plurality of stabilisers each of which is rotatably associated with the base frame about an axis of oscillation lying on a plane orthogonal to the axis of rotation of the turntable, alternatively between a working position, in which it is supported on the ground in addition to or as an alternative to the support arrangement, and a rest position, in which it is raised off the ground; a control system comprising a plurality of sensors, one for each of the stabilisers, wherein each sensor is configured to detect a first parameter indicative of an inclination of the respective stabiliser about its axis of rotation, and an electronic control unit operatively coupled to the plurality of sensors.

A stabilised machine that comprises; a self-propelled base frame movably supported by a motorised ground support arrangement and provided with an upper support plane; a motorised turntable supported on top of the support plane of the base frame and rotatable with respect to an axis of rotation orthogonal to the support plane; an elevating arm, one first end of which is articulated to the turntable and one second opposed free end of which is adapted to be fixed to an operating arrangement; a plurality of stabilisers each of which is rotatably associated with the base frame about an axis of oscillation lying on a plane orthogonal to the axis of rotation of the turntable, alternatively between a working position, in which it is supported on the ground in addition to or as an alternative to the support arrangement, and a rest position, in which it is raised off the ground; a control system comprising a plurality of sensors, one for each of the stabilisers, wherein each sensor is configured to detect a first parameter indicative of an inclination of the respective stabiliser about its axis of rotation, and an electronic control unit operatively coupled to the plurality of sensors.

A method for controlling a hydraulic actuator (2) of a system (1) by means of a valve having a valve element is described. A position of the valve element determines a pressure supplied to a hydraulic actuator (2). In such a method a variable dead band should be minimized. To this end a start position of the valve element is preadjusted as a function of at least one parameter outside the hydraulic actuator (2).

System and methods for a DC powered hydraulic system capable of providing control over pressurized hydraulic fluid delivered to directional valves without the need for a PTO and/or a proportional valve. The hydraulic system controls the output from a battery to a direct current hydraulic pump.

A clamp assembly comprising a pair of clamps may couple to an assembly body. The clamps may pivot to receive material beneath the assembly body. The clamps may include opposing surfaces that define a scoop space beneath the assembly body. Each of the clamps may include a cutting plate. The cutting plate may include a perforating edge configured to extend into the scoop space relative to a corresponding one of the opposing surfaces. The clamp may further include a retention plate. The retention plate may include an inner surface that faces the cutting plate. The cutting plate and the retention plate further define the scoop space between the clamps. The clamp assembly may couple to a lift assembly. The lift assembly may include a hydraulic actuator configured to raise and lower the clamp assembly.