A portable hydraulic power unit includes a frame, a fluid tank supported by the frame, and a manifold supported by the frame. The fluid tank is configured to store a supply of hydraulic fluid for powering a hydraulically-driven tool. A reciprocating pump is mounted on the exterior of the fluid tank and on the exterior of the manifold. The reciprocating pump is secured to the fluid tank and the manifold with fasteners extending through a cylinder body of the reciprocating pump.

A portable hydraulic power unit includes a frame, a fluid tank supported by the frame, and a manifold supported by the frame. The fluid tank is configured to store a supply of hydraulic fluid for powering a hydraulically-driven tool. A reciprocating pump is mounted on the exterior of the fluid tank and on the exterior of the manifold. The reciprocating pump is secured to the fluid tank and the manifold with fasteners extending through a cylinder body of the reciprocating pump.

A portable hydraulic power unit includes a fluid tank supported on a frame, a first pump configured to draw hydraulic fluid from the tank and a second pump configured to draw hydraulic fluid from the tank. The portable hydraulic power unit further includes a two-way valve disposed on a high-flow line extending from an output of the second pump, the two-way valve movable between an open state and a closed state. The two-way valve is electrically-actuated and configured to shift to the open state based on a hydraulic fluid pressure in a combined flow line downstream of the first pump and the second pump exceeding a threshold pressure level. The two-way valve directs the output of the second pump back to the fluid tank when the two-way valve is in the open state.

A trigger guard for a pendant for controlling a hydraulic power unit includes a first prong extending from a front side of a handle of the pendant; a second prong extending from the front side of the handle; a groove disposed between the first prong and the second prong, the groove defined by the first prong, the second prong, and the handle; a first gap disposed between the first prong and a head of the pendant; and a second gap disposed between the second prong and the head. The trigger is disposed between the first prong and the second prong such that the trigger is accessible through the groove, the first gap, and the second gap.

A hydraulic cylinder system and method for operating the hydraulic cylinder system for a hydraulic tool is provided. The hydraulic cylinder system comprises an inner hydraulic cylinder, an outer hydraulic cylinder, a hydraulic ram, a hydraulic pump, and a sequence valve embedded inside the hydraulic pump. The hydraulic pump provides flow into the inner hydraulic cylinder so that during operation of the hydraulic cylinder system, the hydraulic ram extends in a first phase, the sequence valve opens in a transition phase, and the hydraulic ram extends in a second phase.

A pneumatic chamber 20 is configured to include a first pneumatic chamber 21 pressurizing a first piston 11 and a second pneumatic chamber 22 pressurizing a second piston 12. The first pneumatic chamber 21 communicates with the second pneumatic chamber 22. The hydraulic pressure generating unit 55 is internally provided with a hydraulic chamber 30, and the hydraulic chamber 30 is configured to have a first hydraulic chamber 31 pressurized by the first pneumatic chamber 21 via the first piston 11 and a second hydraulic chamber 32 pressurized by the second pneumatic chamber 22 via the second piston 12. The hydraulic pressure generating unit 55 is movable in a thrust direction in a cylinder 2, and the second hydraulic chamber 32 has a function of fixing the moving hydraulic pressure generating unit 55 in the cylinder 2 by causing a thin portion 15 to be elastically deformed in a radial direction due to hydraulic pressure. The first hydraulic chamber 31 outputs hydraulic pressure of the first hydraulic chamber 31, which is increased by the fixing, to an output rod 7.

A cylinder acceleration mechanism includes a buffer tank that supplies and discharges oil to and from a bottom-side line that is connected to a bottom-side chamber of an actuating cylinder, and an inversion lever having an intermediate fulcrum as a rotation axis. The buffer tank includes a buffer chamber with a variable capacity achieved by a seal lid moving back and forth inside of a case, and extends and reduces a length of a coupling rod provided to the seal lid and projects from the case. A bottom-side branching line branched from the bottom-side line is connected to the buffer chamber. The actuating rod of the actuating cylinder and the coupling rod of the buffer tank are coupled to respective ends of the inversion lever. The actuating rod and the coupling rod extend and retract alternately with respect to each other as the inversion lever turns.

An object of the present invention is to provide a work machine that makes it possible to perform, with a simple configuration, speed control of respective actuators and thrust control of a particular actuator that regenerates the flow of a return fluid, at the time of combined operation to simultaneously drive the particular actuator and another actuator. For this purpose, a controller calculates a target thrust that is a target value of a thrust of the particular actuator on the basis of an input amount of an operation device and an output value of a posture sensor, calculates a target meter-out pressure that is a target value of a meter-out pressure of the particular actuator on the basis of the target thrust and a meter-in pressure of the particular actuator, and calculates a regeneration control valve target opening area that is a target value of an opening area of a regeneration control valve on the basis of the target meter-out pressure and the meter-out pressure of the particular actuator.

A first piston (4) which is coupled to an output rod (2) and which is inserted in a housing (3) is driven upward by a pressurized fluid. A second piston (6) which is arranged above the first piston (4) is driven downward. This causes a wedge-type force multiplier (M), arranged above the first piston (4), to carry out force multiplication driving with respect to the output rod (2).

A hydraulic machine unit that can be operated with various working forces, in which working medium is selectively delivered, via a pump-piston accumulator system, to a main cylinder and at least one driving cylinder, wherein at least for one working stroke a pump system of the pump-piston accumulator system is used to provide working medium to a piston accumulator of the pump-piston accumulator system, and then at least for the working stroke at least the main cylinder is charged with a working pressure from the piston accumulator, and wherein at least for a return stroke the at least one driving cylinder is charged with a return stroke pressure from the pump-piston accumulator system, can be of structurally simple configuration if, at reduced working forces, the working pressure is reduced with respect to the piston accumulator pressure prevailing in the piston accumulator.