Abstract: An engine control device is provided including: detection units for detecting a driving state of a work machine using a generator, target engine speed setting units for causing, on the basis of the driving state, a target engine speed set for a case where electric power generation by the generator is OFF to be the same as a target engine speed set for a case where the electric power generation by the generator is ON, and engine target output calculation units for calculating an engine target output during electric power generation OFF that can be output at most when the electric power generation by the generator is OFF, and calculates an engine target output obtained by adding an output corresponding to an electric power generation amount by the generator to the engine target output when the electric power generation by the generator is ON.

Abstract: An engine control device is provided including a detection unit for detecting the operating state of a working machine; a no-load maximum speed computation unit for computing a no-load maximum speed being an engine speed to be increased to the maximum upon a load of the working machine being released, based on the operating state; a target matching speed computation unit for computing a target matching speed being an engine speed to be increased upon a load being applied to the working machine, separately from the no-load maximum speed, based on the operating state; a target engine output computation unit for computing target engine output EL that can be outputted to the maximum, based on the operating state; and an engine control unit for controlling the engine speed between the no-load maximum speed and the target matching speed under a restriction of the target engine output.

Abstract: It is determined that assisting is required when a deviation of a target matching engine speed and a current engine speed is equal to or more than a predetermined value, and for a predetermined period of time since the time point at which it is determined that assisting is required, a target assist engine speed is set at a high rotation target matching engine speed which is more than the target matching engine speed, and thereafter the target assist engine speed is set gradually closer to the target matching engine speed, and an assist torque command value is output to the generator assisting output of the engine, and the engine speed is controlled, so that the engine speed attains the target assist engine speed.

Abstract: An engine control apparatus includes a hydraulic pump driven by an engine, a hydraulic actuator to which pressure oil discharged form the hydraulic pump is supplied, an operation lever configured to operate the hydraulic actuators, a detection means detecting operation amounts of operation lever means, an target flow rate calculation unit (50) calculating an target flow rate of the hydraulic pump based on the operation amount of the operation lever, a first target speed calculation unit (61) calculating a first target speed of the engine according to the target flow rate, a pump output limit value calculation unit (500) limiting the maximum target speed of the engine in an relief operation according to a load pressure of the hydraulic pump, a fourth engine target speed calculation unit (63).

Abstract: A control device of an electric motor includes: an operating state setting unit configured to set an operating state; a maximum output acquiring unit configured to acquire maximum output of the electric motor that is preset according to the operating state set; a speed detecting unit configured to detect a speed of the electric motor; a torque limit value calculating unit configured to calculate a torque limit value based on the speed and the maximum output; and a torque limiting unit configured to limit torque of the electric motor by the torque limit value when accelerating the electric motor.

Abstract: An engine control device is provided including: detection units for detecting a driving state of a work machine using a generator, target engine speed setting units for causing, on the basis of the driving state, a target engine speed set for a case where electric power generation by the generator is OFF to be the same as a target engine speed set for a case where the electric power generation by the generator is ON, and engine target output calculation units for calculating an engine target output during electric power generation OFF that can be output at most when the electric power generation by the generator is OFF, and calculates an engine target output obtained by adding an output corresponding to an electric power generation amount by the generator to the engine target output when the electric power generation by the generator is ON.

Abstract: A work machine includes: hydraulic actuators 21, 22, 23, 31, and 32; a capacitor 61 for storing electric power when a generator motor 44 operates as a generator and for supplying electric power when the generator motor 44 operates as a motor; and a swing electric motor 10, the hydraulic actuators 21, 22, 23, 31, and 32 and the swing electric motor 10 are operated by operation of operating levers 50, 70. The work machine includes an idling stop control unit 110 for stopping the idling of an engine 40 and retains the swing electric motor 10 in an operation prohibited state at least on the condition that stored voltage of the capacitor 61 is predetermined voltage or higher when the neutral states of the operating levers 50, 70 continue for a predetermined stop time during operation of the engine 40.

Abstract: An engine control apparatus includes an engine target speed set unit 51 setting a first target speed through a throttle dial, a relief engine maximum speed calculation unit 52 calculating a second target speed limiting a maximum target speed in a relief operation according to a load pressure of a hydraulic pump, a speed control means controlling an engine speed such that the engine speed is equal to lower one of the first target speed and the second target speed, a determination means determining whether an engine torque assist action of a generator motor is performed, based on a deviation between an target speed and a real speed of the engine. When the determination means determines that the engine torque assist action is performed, the speed control means controls the engine speed to be equal to the target speed through the engine torque assist action of the generator motor.

Abstract: A rotation controller of an electric rotary excavator is provided with a gear drive controller that includes a backlash determination device and a torque limit setting device. With the arrangement, since an output torque of an electric motor is limited by a torque limit when a backlash is eliminated, an excessive torque is prevented from being output. After that, the output torque is gradually changed by an output control device of the gear drive controller. Accordingly, since acceleration and deceleration of a rotary body is performed without causing an operator to feel uncomfortableness, a shock generated when the backlash is eliminated can be suppressed. As a result, smooth rotation operation free from an influence of the backlash can be realized.

Abstract: A method of controlling a hybrid construction machine capable of preventing a system from being rendered inoperative without increasing a capacitance of a capacitor and of inhibiting delay of a swing operation relative to an operation command at the time of swing operation, and the hybrid construction machine are provided. For this purpose, at the time of discharge of the capacitor, actual torque command values are respectively generated by referring to an assist torque limit value corresponding to capacitor voltage of a generator motor and a swing power running torque limit value corresponding to the capacitor voltage of a swing motor, as well as, at the time of charge of the capacitor, an actual target output value of the generator motor is generated.

Abstract: A display device includes a display controller and displays a content based on display signals output from the display controller. The display controller includes: a gauge value converter that converts measurements of a plurality of devices displayed in a predetermined unit into gauge values with the same scale; and a maximum gauge value determiner that determines a maximum one of the gauge values converted by the gauge value converter, so as for the gauge value determined by the maximum gauge value determiner to be displayed.

Abstract: An object of the present invention is to operate the working machine etc. with satisfactory responsiveness as intended by the operator while enhancing engine efficiency, pump efficiency, and the like, where a first engine target revolution ncom1 adapted to a current pump target discharge flow rate Qsum is set, and when determined that the current pump target discharge flow rate Qsum is greater than a predetermined flow rate (10 (L/min)), a revolution nM (e.g., 1400 rpm) greater than an engine low idle revolution nL is set as a second engine target revolution ncom2 determining that operation levers 41 to 44 switched from a non-operation state to an operation state. The engine revolution is controlled so that the second engine target revolution ncom2 is obtained if the second engine target revolution ncom2 is equal to or greater than the first engine target revolution ncom1.

Abstract: A control device of an electric actuator adapted to perform a forward-reverse movement includes a control unit adapted to be operated in a forward direction or a reverse direction in accordance with the forward-reverse movement of the electric actuator. It also includes a pilot circuit, which is connected to the control unit and which generates a forward pilot pressure or a reverse pilot pressure in accordance with the forward operation or the reverse operation of the control unit. The control device has a differential pressure acquiring unit that acquires a differential pressure between a pilot pressure corresponding to an operation direction of the control unit and a pilot pressure, in a direction opposite to the operation direction, and it has a control command generator that generates a control command for controlling the electric actuator based on the differential pressure acquired by the differential pressure acquiring unit.

Abstract: The disclosed rotating parking brake control device obviates the need for an operator to operate an emergency-stop switch. A hybrid controller, to which a brake is connected, outputs a drive control signal to a rotating electric motor to control drive of an upper rotating body and also controls the brake by generating a brake release command signal and outputting the brake release command signal to the brake. A pump controller also generates a brake release command signal, and the brake release command signal generated by the pump controller is transmitted to the hybrid controller through an inter-controller signal line. The brake release command signal is outputted to the brake only when the brake release command signal is generated by the hybrid controller and the brake release command signal is transmitted from the pump controller through the inter-controller signal line.

Abstract: The present invention provides a construction machine where overheating of mounted electric devices can be prevented properly with a simple structure and a method of controlling the construction machine. For this purpose, a pump target discharge flow rate of a hydraulic pump is calculated based on an operated amount of an operating unit, a temperature of an electric device mounted on the construction machine is detected, an engine minimum speed, which is a minimum possible speed of an engine in carrying out low-speed matching for matching output of the engine and pump absorbing horsepower of the hydraulic pump to each other in a low-speed region where speed of the engine is lower than set speed, is calculated by using the detected temperature of the electric device, and a maximum value out of a corresponding speed of the pump target discharge flow rate and the engine minimum speed is generated as a candidate for an engine target speed.

Abstract: A power generation control method of a hybrid construction machine capable of maintaining voltage of a capacitor in an appropriate range while minimizing capacitance of the capacitor and of surely preventing a system from being rendered inoperative, and the hybrid construction machine are provided. For this purpose, swing power corresponding to electric power consumed by a swing motor for swinging a part of a body relative to other parts is sequentially calculated, a value of the calculated swing power is converted to a smaller value, a power generation command of a generator motor is sequentially generated using the converted value, and the generated power generation command is output to an inverter for driving the generator motor.

Abstract: A speed of a hydraulic actuator is matched with that of an electric actuator when the hydraulic actuator and the electric actuator are concurrently actuated. When determination units (71, 72) determine that a boom hydraulic cylinder (31) and a rotation generator motor (11) are concurrently actuated based on a controlled variable of a boom control lever (41) and a controlled variable of a rotation control lever (42), a torque of the rotation generator motor (11) is restricted based on a pump discharge pressure (Pp). Therefore, for example, a torque limit command is generated and output such that a torque limit value (TL2) of the rotation generator motor (11) is decreased with a decrease in discharge pressure (Pp) of a hydraulic pump (3).

Abstract: Example embodiments of the present invention provide the ability to control or set the electromotive force (emf) potential observed in an electronic component by adjusting the resistivity at conducting junctions within it. More specifically, at joints where emf potentials exist due to conducting materials of different types (e.g., two different metals), the resistivity of these conducting junctions is varied, which sets the overall polarity of the emf observed across the component itself. In other words, varying the resistivity at conducting junctions relative to one another, example embodiments control the polarity of the emf within the component itself. As such, the components may then be connected in series or other manner to reduce the overall emf potential induced into a system.

Abstract: In a swing control device installed in an electric rotary excavator (a construction machine), when a leading edge or a trailing edge of a lever signal is sharp due to a quick operation of a swing lever, a gradient as a rise time Ta1 or a fall time Tb1 is provided to the leading edge or the trailing edge of the torque output and the acceleration that are output based on the lever signal so as to somewhat ease the edge. With the arrangement, an impact in acceleration or deceleration of a rotary body can be suppressed. Specifically, a gradient in the acceleration operation is provided such that the rise time Ta1 becomes 0.15 seconds or more, while a gradient in the stop deceleration operation is provided such that the fall time Tb1 becomes 0.1 seconds or more.

Abstract: An engine control apparatus includes a hydraulic pump driven by an engine, a hydraulic actuator to which pressure oil discharged form the hydraulic pump is supplied, an operation lever configured to operate the hydraulic actuators, a detection means detecting operation amounts of operation lever means, an target flow rate calculation unit (50) calculating an target flow rate of the hydraulic pump based on the operation amount of the operation lever, a first target speed calculation unit (61) calculating a first target speed of the engine according to the target flow rate, a pump output limit value calculation unit (500) limiting the maximum target speed of the engine in an relief operation according to a load pressure of the hydraulic pump, a fourth engine target speed calculation unit (63).