Abstract: An inverter/converter as a kind of hybrid unit is composed of a body and a casing covering the body and is disposed in an engine room. An air intake port and an air discharge port each provided with a fan are formed in the casing to configure an internal air cooling device for introducing air present outside the engine room into the casing, allowing the air to flow through the interior of the casing and then discharging it from the air discharge port. A power divider for distributing engine power to a hydraulic pump and a generator-motor is disposed on one of right and left sides of an engine in a rear portion of an upper rotating body. Further, an electric power storage device and the inverter/converter are disposed right and left in parallel behind a cabin and in front of the engine, and a partition wall which defines the engine room is configured by casings of the electric power storage device, the inverter/converter and the power divider.

Abstract: Maximum charging power of a battery (63) is set by a battery-charging power setting unit (75), while maximum discharging power of the battery (63) is set by a battery-discharging power setting unit (76). Lower and upper limit of generator output power is set by a generator output power setting unit (77). A generator/battery power distribution determining unit (81) distributes power between the battery (63) and the generator (62) using the set values above.

Abstract: An object of the invention is to maintain high vehicle driving performance and system efficiency by preventing reductions in the traction characteristic and the maximum driving speed of a vehicle. The invention relates to an electrical system for an electric automotive vehicle for driving the vehicle by supplying an electric power of a direct-current power supply to an electric motor for driving wheels via a semiconductor power converter for driving the wheels such as an inverter and speed-variably driving this electric motor or an electrical system for an electric automotive vehicle using an engine and a direct-current power supply as driving sources. A booster chopper 200 is connected between a battery device 1 or 4 as the direct-current power supply and an inverter 2 or a semiconductor power converter 100, and is controlled so that a direct-current input voltage of the inverter 2 or the like becomes substantially constant.

Abstract: An excavator in which a generator is driven by an engine as a power source. Electric motors are driven by electric power supplied from the generator, and a lower traveling body, an upper turning body, and operating parts of an excavation attachment are operated by the electric motors.

Abstract: Maximum charging power of a battery (63) is set by a battery-charging power setting unit (75), while maximum discharging power of the battery (63) is set by a battery-discharging power setting unit (76). Lower and upper limit of generator output power is set by a generator output power setting unit (77). A generator/battery power distribution determining unit (81) distributes power between the battery (63) and the generator (62) using the set values above.

Abstract: A power control apparatus has a generator power converting circuit (3) for converting power from a generator (2) to DC power to output the DC power to a direct-current line (8), a battery (4), chopper circuits (5, 7) for converting power from a capacitor (6) to DC power to output the DC power to the direct-current line (8), a motor-driving circuit (9) for driving an electric motor (10) based on the power supplied by way of the direct-current line (8), and a power control circuit (23) for controlling the generator power converting circuit (3) and the chopper circuits (5, 7) in such a manner that the voltage of the DC line (8) is maintained at a substantially constant level irrespective of variation of demanded power from a load (11), whereby power just enough for the demanded power from the load (11) is supplied.

Abstract: A working machine, such as an excavator, provided with a condenser, capable of satisfying condensing conditions required for various works, while minimizing the condensers and maintaining a light-weight. The working machine includes a generator and at a an electrically-operated actuator for generating power for operating a work member by electric power generated by the generator. Further, as for charging-discharging electric power, a plurality of kinds of condensers are provided, and the condensers used are selectively switched according to power required, work contents, or the like.

Abstract: There are provided an electric motor driven by (electric) power from a battery; a hydraulic pump driven by the electric motor; a hydraulic motor driven by operating oil discharged from the hydraulic pump; an operating member for performing a predetermined operation by the drive of the hydraulic motor; and operating levers for operating the operating member by switching a flow and a shut-off of the operating oil discharged from the hydraulic pump. The operating levers are operatable between a neutral position at which the hydraulic motor stops operation and an operating position at which the hydraulic motor operates. An accel-trimmer is provided to adjust the supply amount of power from the battery to the electric motor in the state where the operating levers are operated to the operating position.

Abstract: A control apparatus for a hydraulic excavator is capable of carrying out precise operations according to various kinds of classifications of works without requiring switching operations by an operator and management according to work records. The apparatus includes a classification of work discriminating section for recognizing a classification of work being carried out by the hydraulic excavator on the basis of data detected by sensors for detecting an operating amount of a lever for a boom and the like; sections for setting an operating mode of hydraulic pumps absorbing horse power and the like, according to the classification of work recognized; a hydraulic pump control section for controlling the hydraulic pumps according to the set operating mode; and an auto acceleration control section for making effective or invalid the auto acceleration control for controlling speed of an engine to a low speed when work stops.

Abstract: There are provided with an electric motor driven by a battery, a hydraulic pump driven by the electric motor, a proximal actuator for actuating a working member by working oil from the hydraulic pump, a hydraulic motor for moving a working machine body, and an operating lever which can be operated between a neutral position and an operating position. There are provided with a control valve capable of cutting off a supply of working oil to the proximal actuator in a state where operating lever is positioned at an operating position, and a battery capacity sensor for detecting the capacity of the battery. There is provided a controller for outputting a control signal for cutting off a supply of working oil to the proximal actuator to the switching control valve in a state where the battery capacity value detected by the battery capacity sensor is at a level lower than a preset battery capacity reference value. It is possible to positively prevent the machine from being immoved at the working site.

Abstract: The battery-driven hydraulic excavator comprises an electric motor driven by power from the battery, a hydraulic pump driven by the electric motor, and a plurality of hydraulic actuators driven by operating oil from the hydraulic pump. There are provided supply lines for feeding the operating oil in an oil tank from the hydraulic pump into the hydraulic actuators. A differential pressure gauge for detecting the flow rate of operating oil is provided in a main supply line for joining operating oil which were not fed into the hydraulic actuators to return it to the oil tank. Control is made so that power in inverse proportion to the flow rate detected by the differential pressure gauge is supplied to the electric motor. Thereby, the life of the battery can be extended.