Abstract: The hybrid construction machine includes an engine 11, an electric motor/generator 14, a hydraulic pump unit 17, an electricity storage device 16, an inverter 15, a temperature regulator (16D or 16E), and a hybrid control unit 22. The hybrid control unit 22 executes at least one of first control for controlling a warming-up battery temperature regulator 16D so that it increases a temperature of the electricity storage device 16, second control for controlling the inverter 15 so that it reduces the power output from the inverter 15, and third control for controlling a pump capacity control unit 21 so that it reduces the flow rate of a hydraulic fluid delivered from the hydraulic pump unit 17, according to a charge/discharge history of the electricity storage device 16.

Abstract: Provided is a construction machine comprising an energy recovery device for recovering hydraulic fluid energy from a hydraulic actuator and being capable of achieving excellent operability even when the power of the prime mover is changed. The construction machine comprises an engine 1, a hydraulic pump 2, a plurality of hydraulic actuators 31-34, a plurality of control valves 41-44, a plurality of operating devices 71-74, an energy recovery device 80, an operation mode selector switch 76, an engine revolution speed dial 77, a pressure sensor 75, and a controller 90 which controls the flow rate of hydraulic fluid recovered by the energy recovery device based on input signals from the operation mode selector switch, the engine revolution speed dial and the pressure sensor.

Abstract: A work machine is adapted for reduced fuel consumption in regions where swinging by a hydraulic motor is prone to deterioration in efficiency, such as when the operating stroke of the swinging is small. The work machine includes an engine, a hydraulic pump, a swing structure, an electric motor for driving the swing structure, and a hydraulic motor for driving the swing structure, the hydraulic motor being driven by the hydraulic pump, and includes a swing control lever device that commands the swing structure to be driven. A control device operates in either an electric swing mode in which the swing structure is driven mainly by torque of the electric motor or a hydraulic swing mode in which the swing structure is driven mainly by torque of the hydraulic motor, depending on an operating stroke of the control lever device and/or a swing speed of the swing structure.

Abstract: A construction machine, comprising a hydraulic pump, a swing hydraulic motor, a swing electric motor, a delivery capacity regulating device, and a control unit which controls the driving/braking of the swing structure, is configured to comprise an operation amount detection device for detecting the operation amount of the swing control lever and a speed detection device for detecting the speed of the swing electric motor. The control unit includes a hydraulic pump output reduction control unit which takes in an operation amount signal representing the operation amount of the swing control lever detected by the operation amount detection device and a speed signal representing the speed of the swing electric motor detected by the speed detection device and controls the delivery capacity regulating device by calculating a reduction rate of the output of the hydraulic pump based on the detection signals.

Abstract: A work machine prevents a fault in a swing electric motor if an uneven coil temperature increase occurs in the swing electric motor during swing press and related operations. An electricity storage device is connected to the electric motor. An inverter drives the electric motor and a swing control lever issues a command to drive the swing structure. A rotational speed detecting device detects swing speed of the swing structure and a controller controls torque of the electric motor. The controller reads the swing speed of the swing structure detected by the rotational speed detecting device to control such that, when the swing speed is zero, the torque of the electric motor is smaller than a maximum torque value and, when the swing speed is a first rotational speed higher than zero, the torque of the electric motor is the maximum torque value.

Abstract: This invention provides a hybrid construction machine including a swing structure, a hydraulic pump, a hydraulic swing motor driving the swing structure using hydraulic fluid from the hydraulic pump, an electric swing motor driving the swing structure in conjunction with the hydraulic swing motor, a boom cylinder operated simultaneously with the swing structure at times and driven by the hydraulic fluid from the hydraulic pump, a first directional control valve controlling flow of the hydraulic fluid supplied from the hydraulic pump to the hydraulic swing motor, a second directional control valve controlling the flow of the hydraulic fluid returning from the hydraulic swing motor, and a controller and solenoid pressure reducing valves which prevent operation of the second directional control valve when the boom cylinder is operated simultaneously with the swing structure.

Abstract: The hydraulic fluid energy recovery apparatus includes a fluid communication line for holding a bottom-side hydraulic fluid chamber and a rod-side hydraulic fluid chamber of a hydraulic cylinder in fluid communication with each other, a fluid communication valve connected to the fluid communication line for adjusting the pressure and/or flow rate of a hydraulic fluid passing through the fluid communication line in a manner that allows for adjustment of a degree of opening of the fluid communication valve, first pressure detecting means for detecting a signal indicative of pressure at the bottom-side hydraulic fluid chamber of the hydraulic cylinder, an amount-of-operation detecting means for detecting an amount of operation of the operating means, and a control device for capturing the signal of pressure at the bottom-side hydraulic fluid chamber of the hydraulic cylinder detected by the first pressure detecting means.

Abstract: Provided is a work machine including: a variable-displacement pump 2; an actuator 5 driven by a hydraulic fluid delivered from the pump 2; a flow control valve 4 of an open-center type that controls a flow rate of the hydraulic fluid supplied to the actuator 5; a bleed-off line 8a connecting the actuator flow control valve 4 to a tank 6; a bleed-off flow control valve 8 disposed in the bleed-off line 8a; an operating device 3 that specifies operation of the actuator 5; a bleed-off control device 14 that controls a degree of opening of the bleed-off flow control valve 8 in accordance with an amount of manipulation of the operating device 3; and a pump control device 15 that controls, in accordance with the degree of opening of the bleed-off flow control valve 8, a pump flow rate by correcting a reference pump flow rate that is based on the amount of manipulation of the operating device 3.

Abstract: Provided is construction machinery that is capable of greatly reducing the amount of fuel consumption by making effective use of recovered energy. The construction machinery has a first hydraulic pump 3 for discharging hydraulic oil for driving an actuator 6, a second hydraulic pump 9, a second prime mover 7 for driving the second hydraulic pump 9, energy storage device 8 for storing energy for driving the second prime mover 7, and a hydraulic oil supply circuit 10 including a hydraulic oil switching section 11c that accepts the hydraulic oil discharged from the first hydraulic pump and the hydraulic oil discharged from the second hydraulic pump and supplies either the mixture of the accepted hydraulic oils or a selected one of the accepted hydraulic oils to the actuator 6.

Abstract: A construction machine includes: a swing structure (50); a hydraulic pump (1); a hydraulic motor (3) for driving the swing structure (50) using hydraulic fluid from the hydraulic pump (1); an electric motor (14) for driving the swing structure (50) with or without the aid of the hydraulic motor (3); and a hydraulic actuator (16) driven by the hydraulic fluid from the hydraulic pump 1, the hydraulic actuator can be operated together with the swing structure (50). When the swing structure (50) is operated together with the hydraulic actuator (16), only the electric motor (14) is used to swing the swing structure (50).

Abstract: Provided is a construction machine comprising an energy recovery device for recovering hydraulic fluid energy from a hydraulic actuator and being capable of achieving excellent operability even when the power of the prime mover is changed. The construction machine comprises an engine 1, a hydraulic pump 2, a plurality of hydraulic actuators 31-34, a plurality of control valves 41-44, a plurality of operating devices 71-74, an energy recovery device 80, an operation mode selector switch 76, an engine revolution speed dial 77, a pressure sensor 75, and a controller 90 which controls the flow rate of hydraulic fluid recovered by the energy recovery device based on input signals from the operation mode selector switch, the engine revolution speed dial and the pressure sensor.

Abstract: In a hybrid construction machine, there is provided a drive control device which realizes in, as a simple a structure as possible, control means of a motor generator, which is capable of preventing rapid decreases in the state of charge. The control means, which calculates a motor torque command value to be output to the motor generator, is characterized by calculating the motor torque command value, based on a difference between an actual state-of-charge and a prescribed target state-of-charge and a torque margin obtained by a difference between a maximum torque of an engine determined based on an actual rotational speed of the engine and an actual torque of the engine.

Abstract: Disclosed is a hybrid-type construction machine equipped with a swing hydraulic motor 27 and a swing electric motor 25 in combination to save energy, the construction machine ensuring high operability of a swing body 20 and providing high energy efficiency. In accordance with the amount of manipulation of a swing control lever 72, the construction machine changes a rate of a torque of the swing electric motor 25 with respect to that of the swing hydraulic motor 27. The construction machine also controls a relief pressure and the torque of the swing electric motor 25 in accordance with the amount of manipulation of a swing control lever 72, a pressure of the swing hydraulic motor 27, and a rotating speed of the swing electric motor 25.

Abstract: In hybrid construction machine employing a hydraulic motor and an electric motor for the driving of the swing structure, satisfactory operability of a combined operation of the swing structure and other actuators is secured irrespective of the operating status of the electric motor. A control device of the hybrid construction machine executes control selected from: hydraulic/electric complex swing control for driving the swing structure by total torque of the electric motor and the hydraulic motor when a swing operating lever device is operated; and hydraulic solo swing control for driving the swing structure by the torque of the hydraulic motor alone when the swing operating lever device is operated.

Abstract: A hybrid construction machine is provided with a variable displacement hydraulic pump 1 which supplies hydraulic oil to a hydraulic actuator, an engine 2 which is provided to be able to drive and rotate the hydraulic pump 1, an electric motor 3 which is provided to be able to drive and rotate the hydraulic pump 1, an engine control dial 4, a controller 4 and an operating lever 5. The controller changes the rotation speed of the engine 2 to reduce fuel consumption according to power generated by the engine 2, and changes displacement of the hydraulic pump 1 based on the rotation speed of the engine 2, the dial position of the engine control dial 4 and the amount of operation on the operating lever 5.

Abstract: Target rotation speed setup section for setting a target engine rotation speed; load detection for detecting a hydraulic pump load; an assist output computation section for calculating an assist output to be generated by a motor generator in accordance with a rotation speed deviation ?N, which is the difference between an actual and target rotation speed, or in accordance with the hydraulic pump load; an absorption torque upper limit computation section for calculating an absorption torque upper limit value of the hydraulic pump; and an operation signal generation section for generating the operation signal to be output to a pump displacement adjustment device. When the rotation speed deviation ?N is equal to or more than a setting NC determined in accordance with the assist output value, the absorption torque upper limit computation section reduces the absorption torque upper limit value of the hydraulic pump from the calculated value.

Abstract: In hybrid construction machine employing a hydraulic motor and an electric motor for the driving of the swing structure, satisfactory operability of a combined operation of the swing structure and other actuators is secured irrespective of the operating status of the electric motor. A control device of the hybrid construction machine executes control selected from: hydraulic/electric complex swing control for driving the swing structure by total torque of the electric motor and the hydraulic motor when a swing operating lever device is operated; and hydraulic solo swing control for driving the swing structure by the torque of the hydraulic motor alone when the swing operating lever device is operated.

Abstract: Construction machinery that can achieve a great fuel reduction effect through an efficient use of recovered energy is provided. The Construction machinery includes at least two actuators 7 and 8, a main pump 3 that generates hydraulic energy for driving the actuators 7 and 8, flow control means 4 disposed between the main pump 3 and the actuators 7 and 8, an additional energy generating means 11 that generates energy to be added to the hydraulic energy, and a control means 20 that reduces hydraulic energy generated by the main pump 3 when the additional energy generating means 11 generates energy. The construction machinery further comprises changeover means 12d, 12e, and 12f that selectively change a location at which the energy from the additional energy generating means 11 is to be added according to the actuators 7 and 8. The control means 20 changes a reduction rate of the hydraulic energy generated by the main pump 3 depending on a specific actuator 7 or 8 to which the energy is to be added.

Abstract: The present invention includes a target rotation speed setup section (17) for setting a target rotation speed of an engine (1); load detection means (21) for detecting a load on a hydraulic pump (3); an assist output computation section (19) for calculating an assist output to be generated by a motor generator in accordance with a rotation speed deviation ?N, which is the difference between an actual rotation speed and the target rotation speed, or in accordance with the load on the hydraulic pump; an absorption torque upper limit computation section (23) for calculating an absorption torque upper limit value of the hydraulic pump (3); and an operation signal generation section (24) for generating the operation signal to be output to a pump displacement adjustment device (45).

Abstract: In a motion control system for a vehicle including control means for controlling a yaw moment of the vehicle; first detection means for detecting a longitudinal velocity (V) of the vehicle; second detection means for detecting a lateral jerk (Gy_dot) of the vehicle; and third detection means for detecting a yaw angular acceleration (r_dot) of the vehicle, the yaw moment of the vehicle is controlled by the control means so that a difference between the yaw angular acceleration (r_dot) detected by the third detection means and a value (Gy_dot/V) obtained by the lateral jerk (Gy_dot) of the vehicle detected by the second detection means by the longitudinal velocity (V) detected by the first detection means becomes small.