An example robot includes movable members, a hydraulic system including at least (i) hydraulic actuators configured to operate the movable members, and (ii) a source of hydraulic fluid, and a controller. The controller may be configured to: determine a task to be performed by the robot, where the task includes a plurality of phases; cause hydraulic fluid having a first pressure level to flow from the source to the hydraulic actuators for the robot to perform a first phase of the plurality of phases of the task; based on a second phase of the task, determine a second pressure level for the hydraulic fluid; and adjust, based on the second pressure level, operation of the hydraulic system before the robot begins the second phase of the task.

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 multi-way poppet valve and methods for using the same are provided. In one embodiment, the poppet valve includes a manifold and a poppet assembly including an inner poppet and an outer poppet defining one or more lands. The poppet assembly can dimensioned for receipt within a bore of the manifold and configured to move longitudinally within the manifold. The inner poppet and the outer poppet can also be formed in two separate pieces that are capable of moving with respect to one another. This design can allow the lands of the poppet assembly to form fluid-tight seals (e.g., metal-metal, metal-gasket, etc.) with the manifold. In this manner, the poppet valve can move longitudinally between open and closed positions where the fluid-tight seals respectively allow or inhibit fluid flow between selected ports of the valve.

A double-loop control system with a single hydraulic motor relates to a technical field of hydraulic transmission control, including a hydraulic motor (1), a positive control loop (2), a negative control loop (3), a hydraulic pump (4), an accumulator (5), and an oil tank, wherein the hydraulic motor (1) adopts a unique thrust structure with four inlet/outlet ports; the positive control loop (2) and the negative control loop (3) independently control the hydraulic motor (1), wherein the positive control loop (2) and the negative control loop (3) drive together or only one drives; or braking kinetic energy and potential energy of loads are stored in the accumulator (5) for energy recovery. The present invention uses only one hydraulic motor for satisfying different work conditions and different load driving requirements with advantages such as simple structure, high system reliability and high energy efficiency.

A hydraulic apparatus for a hydraulic work vehicle capable of supplying pressure oil to any of a bucket cylinder (20), an arm cylinder (21), a boom cylinder (22), a swing cylinder (25), a blade cylinder (13), a turning hydraulic motor (62), a left traveling hydraulic motor (63), a right traveling hydraulic motor (64), and a PTO hydraulic motor (65) by a first hydraulic pump (P1), a second hydraulic pump (P2), or a third hydraulic pump (P3). The pressure oil can be branched off from a discharge oil passage (28) of the third hydraulic pump (P3) and supplied through an external pipe (71) to a downstream side of a load check valve (46) disposed on an oil passage communicating with a pump port (36p) of a PTO control valve (36) for switching supply of pressure oil from the second hydraulic pump (P2) to an external hydraulic work machine (16).

A shovel may be provided with a swing hydraulic motor, a relief valve provided on the swing hydraulic motor, and an accumulator part that supplies to the swing hydraulic motor a working oil having a pressure lower than a relief pressure of the relief valve. The accumulator part may accumulate the working oil on a braking side of the swing hydraulic motor. The accumulator part may discharge the working oil to an upstream of a main pump.

A control system of a hybrid construction machine includes a regeneration passage switching valve having a normal position where flow of working fluid is blocked, and a regeneration position allowing for the working fluid to flow from main passages to a regeneration motor when a working fluid pressure of the main passages reaches a set pressure during operation of the actuators, and an assist switching valve having a normal position proportionally dividing the working fluid of an assist passage into a regeneration passages, a first switching position supplying more working fluid of the assist passage to one of the main passages when that the one has a higher working fluid pressure, and a second switching position supplying more working fluid of the assist passage to the other one of the main passages when that the other one has a higher working fluid pressure.