Abstract: A work machine is capable of detecting an abnormality in the amount of soot in exhaust gas in an exhaust pipe upstream of an exhaust gas aftertreatment device. The work machine includes: an exhaust gas sensor which detects the amount of soot contained in exhaust gas between an engine and an exhaust gas aftertreatment device and generates a soot amount detection signal; and a controller into which the detection signal is input. The controller includes an abnormality judgment section that makes an abnormality judgment on whether or not the detected soot amount is abnormal, and a threshold setting section that sets a soot amount threshold that is a threshold for making the abnormality judgment. The abnormality judgment section judges an abnormality when the value of the soot amount corresponding to the soot amount detection signal is larger than the soot amount threshold.

Abstract: A work machine is capable of detecting an abnormality in the amount of soot in exhaust gas in an exhaust pipe upstream of an exhaust gas aftertreatment device. The work machine includes: an exhaust gas sensor which detects the amount of soot contained in exhaust gas between an engine and an exhaust gas aftertreatment device and generates a soot amount detection signal; and a controller into which the detection signal is input. The controller includes an abnormality judgment section that makes an abnormality judgment on whether or not the detected soot amount is abnormal, and a threshold setting section that sets a soot amount threshold that is a threshold for making the abnormality judgment. The abnormality judgment section judges an abnormality when the value of the soot amount corresponding to the soot amount detection signal is larger than the soot amount threshold.

Abstract: Provided is a hybrid construction machine capable of appropriate control of engine speed based on a total load torque, reduction in energy loss due to the power for auxiliary devices and efficient operation of the engine and the generator motor, including a hydraulic pump, a generator motor, an engine, and a control device. The control device includes a total load torque determination section determining a total load torque, the sum of load torques for the hydraulic pump and the generator motor, and an engine speed control section controlling the engine speed based on the total load torque. The engine speed control section performs a regulation control of increasing the engine speed as the total load torque decreases under a high load torque condition and performs an isochronous control of maintaining the engine speed at a constant target speed N2 under a low load torque condition.

Abstract: Provided is a hydraulic driving apparatus including a calculation section calculating a temporary target engine rotation speed corresponding to an engine operation amount, a calculation section calculating a temporary target pump displacement volume based on first-control and second-control target pump displacement volumes corresponding to an actuator operation amount and a pump load pressure, and a command section calculating a final target engine rotation speed and a final target pump displacement volume to output commands. The command section calculates a target pump discharge amount from the temporary target engine rotation speed and the temporary target pump displacement volume, sets the final target pump displacement volume to one larger than the temporary target pump displacement volume, and sets the final target engine rotation speed to one being lower than the temporary target engine rotation speed and allowing a pump discharge amount equivalent to the target pump discharge amount to be obtained.

Abstract: A configuration is provided to directly utilize the power of an engine as the power of a hydraulic pump, and to efficiently perform power generation and engine assist. The configuration is provided with an engine; a generator which is configured to generate electric power by an operation of the generator using the power of the engine; a battery which is configured to store the electric power generated by the generator; a motor which is configured to be operated by the power of the engine and by the electric power of the battery; a hydraulic pump connected to the motor so as to be driven by operation of the motor; and a power divider connected to the engine, the generator, and the motor so that the power of the engine is distributed to the generator and to the motor.

Abstract: Provided is a hybrid construction machine capable of appropriate control of engine speed based on a total load torque, reduction in energy loss due to the power for auxiliary devices and efficient operation of the engine and the generator motor, including a hydraulic pump, a generator motor, an engine, and a control device. The control device includes a total load torque determination section determining a total load torque, the sum of load torques for the hydraulic pump and the generator motor, and an engine speed control section controlling the engine speed based on the total load torque. The engine speed control section performs a regulation control of increasing the engine speed as the total load torque decreases under a high load torque condition and performs an isochronous control of maintaining the engine speed at a constant target speed N2 under a low load torque condition.

Abstract: A control device is configured to sufficiently reduce the drive loss of a hydraulic pump. The control device is provided with a controller configured to control a regeneration valve to switch to a regeneration state, and to control the flow rate of a second hydraulic pump to reduce the ejection flow rate of the second hydraulic pump in accordance with regeneration of hydraulic oil through the regeneration valve when a combined operation of lowering a boom and pressing an arm is performed. The controller outputs a command for setting the number of rotations of an engine to be smaller than the rotation number designated by a rotation number designating unit when the ejection flow rate of the second hydraulic pump is not larger than a predetermined flow rate during the combined operation.

Abstract: A hybrid construction machine that enables to efficiently cool a generator motor, while suppressing an increase in the entire length of a power unit. A motor housing is provided with a bulging portion which is configured to axially bulge from the inner periphery of a motor side connection surface toward an engine over the entire circumference thereof around an axis, and to engage with the inside of an engine housing; and a coolant passage which is configured to flow a coolant for cooling a stator therethrough. The inner peripheral surface of the motor housing including the inner peripheral surface of the bulging portion is configured to come into plane contact with the outer peripheral surface of the stator. The coolant passage is disposed at a position axially displaced from the motor side connection surface.

Abstract: Provided is a hybrid construction machine preventing an electrical storage device from overcharge, including a hydraulic actuator, a hydraulic pump, a generator-motor which performs electric generator and motor actions, an engine, an electric actuator which generates regenerative electric power, an electrical storage device which performs a charge-and-discharge action with the generator-motor and the electric actuator, a charge-rate detector which detects a charge rate C1 of the electrical storage device, and a control section which controls an operation of the generator-motor and a charge-and-discharge action of the electrical storage device. The control section, when the charge rate C1 exceeds a set value Cs, performs overcharge-prevention control of making assist power by the electric motor action of the generator-motor be greater than that when C1?Cs, the set value Cs predetermined as a charge rate at which receiving the regenerative electric power can overcharge the electrical storage device.

Abstract: Provided is a hybrid construction machine capable of preventing overcharge, comprising: an engine; a generator-motor; a hydraulic pump; a hydraulic actuator to be operated by the hydraulic pump as a hydraulic pressure source; an actuator regeneration section to make a regenerative action of generating actuator regenerated-electric-power through return fluid from the hydraulic actuator; an electric storage device; a charging-rate detector; and a control section. The control section performs: causing the electric storage device to be charged with electric power generated by the generator-motor and the actuator regenerated-electric-power; causing the generator-motor to make a motor action through electric power stored in the electric storage device to assist the engine; and a regeneration control including stopping the generator action and restricting the actuator regenerated-electric-power, when a detected charging rate of the electric storage device is not smaller than a preset charging-rate limitation value.

Abstract: Provided is a hydraulic driving apparatus including a calculation section calculating a temporary target engine rotation speed corresponding to an engine operation amount, a calculation section calculating a temporary target pump displacement volume based on first-control and second-control target pump displacement volumes corresponding to an actuator operation amount and a pump load pressure, and a command section calculating a final target engine rotation speed and a final target pump displacement volume to output commands. The command section calculates a target pump discharge amount from the temporary target engine rotation speed and the temporary target pump displacement volume, sets the final target pump displacement volume to one larger than the temporary target pump displacement volume, and sets the final target engine rotation speed to one being lower than the temporary target engine rotation speed and allowing a pump discharge amount equivalent to the target pump discharge amount to be obtained.

Abstract: A slewing-type working machine includes: an electric storage device capable of being charged with regenerative electric power for regenerating slewing energy of an upper slewing body while functioning as an electric power source for an electric slewing motor; an electric storage device and electric storage device controller detecting whether the electric storage device is under a normal condition with sufficient capacity to regenerate the slewing energy or under an abnormal condition without sufficient capacity; and a controller controlling a velocity of the electric slewing motor based on a result of detection by the electric storage device and electric storage device controller, wherein the controller performs a velocity limiting control for limiting a maximum velocity of the electric slewing motor when the electric storage device is under the abnormal condition.

Abstract: The axial lengths of coupling portions of a flywheel, a rotor shaft, and a pump shaft are reduced to reduce the axial length of an entire power unit. A crankshaft 4 and a flywheel 8 are directly coupled to each other and the flywheel 8 and a rotor shaft 5 are directly coupled to each other. A coupling 20 is directly coupled to an end face of the rotor shaft 5 on the opposite side to the flywheel 8. A pump shaft 6 is connected to the coupling 20. Coupling surfaces of the flywheel 8 and the rotor shaft 5 and coupling surfaces the rotor shaft 5 and the coupling 20 are arranged within a width range of a coil 19.

Abstract: Provided is a construction machine capable of achieving an energy conservation effect while restraining overcharge of an electrical storage device, including an engine, a slewing electric motor, an electrical storage device, a generator-motor, and an assist controller which causes the generator-motor to assist the engine to consume an electric power equal to or more than an electric power equal to a difference between the regeneration power and the maximum allowable charge amount, when a regeneration power regenerated by the slewing electric motor is equal to or more than a maximum allowable charge amount which is a maximum amount of an electric power within which the electrical storage device can be charged.

Abstract: A configuration is provided to directly utilize the power of an engine as the power of a hydraulic pump, and to efficiently perform power generation and engine assist. The configuration is provided with an engine; a generator which is configured to generate electric power by an operation of the generator using the power of the engine; a battery which is configured to store the electric power generated by the generator; a motor which is configured to be operated by the power of the engine and by the electric power of the battery; a hydraulic pump connected to the motor so as to be driven by operation of the motor; and a power divider connected to the engine, the generator, and the motor so that the power of the engine is distributed to the generator and to the motor.

Abstract: Provided is a hybrid construction machine capable of preventing overcharge, comprising: an engine; a generator-motor; a hydraulic pump; a hydraulic actuator to be operated by the hydraulic pump as a hydraulic pressure source; an actuator regeneration section to make a regenerative action of generating actuator regenerated-electric-power through return fluid from the hydraulic actuator; an electric storage device; a charging-rate detector; and a control section. The control section performs: causing the electric storage device to be charged with electric power generated by the generator-motor and the actuator regenerated-electric-power; causing the generator-motor to make a motor action through electric power stored in the electric storage device to assist the engine; and a regeneration control including stopping the generator action and restricting the actuator regenerated-electric-power, when a detected charging rate of the electric storage device is not smaller than a preset charging-rate limitation value.

Abstract: A control device is configured to sufficiently reduce the drive loss of a hydraulic pump. The control device is provided with a controller configured to control a regeneration valve to switch to a regeneration state, and to control the flow rate of a second hydraulic pump to reduce the ejection flow rate of the second hydraulic pump in accordance with regeneration of hydraulic oil through the regeneration valve when a combined operation of lowering a boom and pressing an arm is performed. The controller outputs a command for setting the number of rotations of an engine to be smaller than the rotation number designated by a rotation number designating unit when the ejection flow rate of the second hydraulic pump is not larger than a predetermined flow rate during the combined operation.

Abstract: Provided is a hybrid construction machine preventing an electrical storage device from overcharge, including a hydraulic actuator, a hydraulic pump, a generator-motor which performs electric generator and motor actions, an engine, an electric actuator which generates regenerative electric power, an electrical storage device which performs a charge-and-discharge action with the generator-motor and the electric actuator, a charge-rate detector which detects a charge rate C1 of the electrical storage device, and a control section which controls an operation of the generator-motor and a charge-and-discharge action of the electrical storage device. The control section, when the charge rate C1 exceeds a set value Cs, performs overcharge-prevention control of making assist power by the electric motor action of the generator-motor be greater than that when C1?Cs, the set value Cs predetermined as a charge rate at which receiving the regenerative electric power can overcharge the electrical storage device.

Abstract: Provided is a construction machine capable of achieving an energy conservation effect while restraining overcharge of an electrical storage device, including an engine, a slewing electric motor, an electrical storage device, a generator-motor, and an assist controller which causes the generator-motor to assist the engine to consume an electric power equal to or more than an electric power equal to a difference between the regeneration power and the maximum allowable charge amount, when a regeneration power regenerated by the slewing electric motor is equal to or more than a maximum allowable charge amount which is a maximum amount of an electric power within which the electrical storage device can be charged.

Abstract: A controller includes a storage unit that stores a map in which an operation amount and an upper limit value of suction torque of a hydraulic pump are associated with each other, for each operation content identified by a cylinder that is an operation object out of the cylinders, and by a direction of operation performed on this cylinder; an operation torque determination unit that determines the upper limit value of suction torque for each cylinder by using the map stored in the storage unit when an actuation command relating to at least one cylinder is input by an operation lever; a high-level selection unit that selects the maximum upper limit value of suction torque out of the upper limit values of suction torque determined by the operation torque determination unit; and a regulator that regulates a displacement of the hydraulic pump so as to obtain torque equal to or lower than the suction torque selected by the high-level selection unit.