Provided is hybrid construction machine that can charge/discharge an electrical storage device appropriately and can suppress stop of an engine accompanying sharp increase of a load. The present invention includes a hybrid controller 22 that controls power of a hydraulic pump 17 and electric power of an inverter 15 in response to storage battery characteristics of the electrical storage device 16, and an output command unit 22F of the hybrid controller 22 is configured to control at least either one of the power of the hydraulic pump 17 and the electric power of the inverter 15 on the basis of at least either one of electric current or voltage of the storage battery characteristics and at least either one of temperature or a state of charge of the storage battery characteristics.

A controller calculates the ratio between the sum of estimated demanded powers of a plurality of first actuators and the sum of estimated demanded powers of a plurality of second actuators, and calculates, on the basis of the ratio, first and second command values for adjusting allocation between a first allowable torque of a first pump and a second allowable torque of a second pump, and first and second regulators adjust the first and second allowable torques, on the basis of first and second output pressures of first and second torque control valves, such that the first and second allowable torques become values to which a predetermined allowable torque is allocated according to the ratio described above, and control the delivery flow rates of the first and second pumps such that the respective consumed torques of the first and second pumps do not become larger than the first and second allowable torques. Thus, the present invention efficiently performs torque allocation between the first and second pumps (a plurality of hydraulic pumps) to thereby enable effective utilization of the torque generated by the prime mover without wasting the torque.

The present disclosure relates to a hydraulic circuit, comprising: a hydraulic displacement unit for driving an implement; a hydraulic machine fluidly connected or selectively fluidly connected with the hydraulic displacement unit the hydraulic machine having a fixed hydraulic displacement; an electric machine drivingly engaged or selectively drivingly engaged with the hydraulic machine; a hydraulic pump fluidly connected or selectively fluidly connected with the hydraulic displacement unit, the hydraulic pump having a variable hydraulic displacement; and an electric motor drivingly engaged or selectively drivingly engaged with the hydraulic pump.

A controller calculates the ratio between the sum of estimated demanded powers of a plurality of first actuators and the sum of estimated demanded powers of a plurality of second actuators, and calculates, on the basis of the ratio, first and second command values for adjusting allocation between a first allowable torque of a first pump and a second allowable torque of a second pump, and first and second regulators adjust the first and second allowable torques, on the basis of first and second output pressures of first and second torque control valves, such that the first and second allowable torques become values to which a predetermined allowable torque is allocated according to the ratio described above, and control the delivery flow rates of the first and second pumps such that the respective consumed torques of the first and second pumps do not become larger than the first and second allowable torques. Thus, the present invention efficiently performs torque allocation between the first and second pumps (a plurality of hydraulic pumps) to thereby enable effective utilization of the torque generated by the prime mover without wasting the torque.

The present disclosure relates to a hydraulic circuit comprising: a hydraulic displacement unit for driving an implement; a hydraulic machine fluidly connected or selectively fluidly connected with the hydraulic displacement unit the hydraulic machine having a fixed hydraulic displacement; an electric machine drivingly engaged or selectively drivingly engaged with the hydraulic machine; a hydraulic pump fluidly connected or selectively fluidly connected with the hydraulic displacement unit, the hydraulic pump having a variable hydraulic displacement; and an electric motor drivingly engaged or selectively drivingly engaged with the hydraulic pump.

A movable-blade operation system for a hydraulic machine according to an embodiment includes an oil hydraulic cylinder installed within a rotational shaft, a bidirectional pump, a pump drive motor, a control unit, and an oil head installed in the hydraulic machine. The bidirectional pump selectively feeds pressurized hydraulic oil to one of a first cylinder chamber and a second cylinder chamber. The oil head couples the rotational shaft rotatably, and the hydraulic oil fed from the bidirectional pump to the first cylinder chamber and the second cylinder chamber flows through the oil head. The bidirectional pump, the pump drive motor, and the control unit are installed outside the hydraulic machine.

A pump device includes a variable capacity first pump, a tilt actuator that controls a tilt angle of a swash plate of the first pump in accordance with the control pressure, a regulator that regulates the control pressure in accordance with a front-rear differential pressure of a control valve, a fixed capacity second pump driven by the same drive source as the first pump, the control actuator that operates in accordance with the front-rear differential pressure a resistor so as to drive the regulator to reduce the control pressure in response to an increase in the front-rear differential pressure of the resistor, an auxiliary passage that leads an auxiliary pressure to the control actuator, the auxiliary pressure acting on the control actuator against a upstream pressure of the resistor, and a switch valve that switches between connecting and shutoff the auxiliary passage.

A pump device includes a variable capacity first pump, a tilt actuator that controls a tilt angle of a swash plate of the first pump in accordance with the control pressure, a regulator that regulates the control pressure in accordance with a front-rear differential pressure of a control valve, a fixed capacity second pump driven by the same drive source as the first pump, the control actuator that operates in accordance with the front-rear differential pressure a resistor so as to drive the regulator to reduce the control pressure in response to an increase in the front-rear differential pressure of the resistor, an auxiliary passage that leads an auxiliary pressure to the control actuator, the auxiliary pressure acting on the control actuator against a upstream pressure of the resistor, and a switch valve that switches between connecting and shutoff the auxiliary passage.

A pump device includes a tilting actuator for controlling a tilting angle of a swash plate in a variable capacity first pump, a regulator for adjusting a control pressure in accordance with a front-rear differential pressure of a control valve, and a control actuator for driving the regulator in accordance with a front-rear differential pressure of a resistor to which the working oil discharged from a fixed capacity second pump is led, and in the control actuator, a pressure receiving area of a control piston on which an auxiliary pressure against an upstream pressure of the resistor acts is set so that an auxiliary driving force corresponds to a lowered amount of a differential-pressure driving force with switching of a rotation speed of a drive source from a first rotation speed to a second rotation speed.

A hydraulic system, preferably for actuating and engaging a mobile slurry pump, includes a primary circuit, actuating a first hydraulic consumer, which circuit has a hydraulic drive assembly including at least one motor-driven hydraulic pump. The hydraulic system further includes a secondary circuit, actuating a second hydraulic consumer, which circuit has a second hydraulic drive assembly including at least one additional motor-driven hydraulic pump. In a first operating state, hydraulic oil from a common tank can be admitted to the hydraulic consumers arranged in the primary circuit and in the secondary circuit via the hydraulic drive assemblies thereof, independently of one another. In a second operating state, a portion of the hydraulic oil is supplied from the primary circuit to the secondary circuit to actuate the second consumer.