Abstract: To stop, in an emergency, a revolving superstructure quickly from rotating while preventing damage of a mechanical brake. A revolving superstructure is driven swiveling using a permanent magnetic-type swiveling electric motor; in an emergency, such as a malfunction in a drive or control system for the swiveling electric motor, allowing electric power generated in the electric motor due to inertial rotation to be consumed in an external braking resistor so as to make an electric braking action; and a mechanical brake is activated to stop the rotation and hold the stopped revolving superstructure when a rotation speed of the revolving superstructure becomes equal to or lower than a preset value.

Abstract: A parking brake is released by a controller and a rotating electric motor is speed-feedback-controlled or position-feedback-controlled to stop and hold an upper rotating body if at least one of arm operation, bucket operation, and travel operation is carried out in a rotating stopped state and with respect to the arm operation and the bucket operation, cylinder thrust of an arm cylinder or a bucket cylinder is greater or equal to a set value. Thereby, a parking brake and a rotating driving part can be prevented from being damaged by rotating external force generated by excavation reaction force or the like and a rotating body can be stopped and held.

Abstract: A brake unit of a rotating drive apparatus includes a piston arranged around a vertically extending rotation shaft body in a non-contact state actionably in the vertical direction, a fixed plate arranged below the piston, and a frictional plate arranged between the piston and the fixed plate rotatably together with the rotation shaft body as well as slidably along the rotation shaft body. The brake unit generates a brake torque by downwardly actuating the piston so as to press the friction plate onto the fixed plate with the piston and the brake unit cancels the braking by upwardly actuating the piston. The brake unit also includes coil springs raising the frictional plate during canceling the braking, to a position between the piston and the faxed plate in a non-contact state with either of them.

Abstract: To stop, in an emergency, a revolving superstructure quickly from rotating while preventing damage of a mechanical brake. A revolving superstructure is driven swiveling using a permanent magnetic-type swiveling electric motor; in an emergency, such as a malfunction in a drive or control system for the swiveling electric motor, allowing electric power generated in the electric motor due to inertial rotation to be consumed in an external braking resistor so as to make an electric braking action; and a mechanical brake is activated to stop the rotation and hold the stopped revolving superstructure when a rotation speed of the revolving superstructure becomes equal to or lower than a preset value.

Abstract: A parking brake is released by a controller and a rotating electric motor is speed-feedback-controlled or position-feedback-controlled to stop and hold an upper rotating body if at least one of arm operation, bucket operation, and travel operation is carried out in a rotating stopped state and with respect to the arm operation and the bucket operation, cylinder thrust of an arm cylinder or a bucket cylinder is greater or equal to a set value. Thereby, a parking brake and a rotating driving part can be prevented from being damaged by rotating external force generated by excavation reaction force or the like and a rotating body can be stopped and held.

Abstract: In a neutral range preset, there are set a zone for stopping and holding a rotating body only by a mechanical brake, a zone for holding the body only by performing position holding control, and a zone for simultaneously exerting both effects, i.e., the effect of the mechanical brake and the effect of the holding control. On-the-spot holding torque generated when the position holding control is performed is stored. The higher of the on-the-spot holding torque stored and accelerating torque according to an operation amount of the body at a rotation starting time is set as electric motor torque for acceleration. When performing a pressing work including pressing a bucket against an object for work, torque control is carried out according to the operation amount.

Abstract: A device, mounted on a hydraulic excavator, for allowing each of first and second electric motors (13), (14) to generate power by using electric power supplied from a power supply having a predetermined capacity, and actuating a boom cylinder (6), an arm cylinder (7), etc. using the generated power. Electric motor controllers (24), (25), respectively control power that is generated by the electric motors (13), (14) so that, in machine-operation, powers generated by the electric motors (13), (14) may be equal to or less than predetermined rated outputs, and the total amount of powers generated simultaneously by the electric motors (13), (14) correspond to the maximum capacity of the power supply.

Abstract: A hybrid system working machine, during a normal working time, operated by a normal operation mode that the output of a power generator and the accumulated power of a capacitor are used while the engine is operated over a high-efficiency range at a low output. Switching of a selector switch to a high-speed running mode position and running operation enable long-distance and high-speed running of an increase in engine output by a high-output operation mode.

Abstract: In a neutral range preset, there are set a zone for stopping and holding a rotating body only by a mechanical brake, a zone for holding the body only by performing position holding control, and a zone for simultaneously exerting both effects, i.e., the effect of the mechanical brake and the effect of the holding control. On-the-spot holding torque generated when the position holding control is performed is stored. The higher of the on-the-spot holding torque stored and accelerating torque according to an operation amount of the body at a rotation starting time is set as electric motor torque for acceleration. When performing a pressing work including pressing a bucket against an object for work, torque control is carried out according to the operation amount.

Abstract: In a construction machine comprising an electric motor 6 for driving a rotational system, an operating member for instructing an operation of the electric motor 6, and a controller 9 for controlling the electric motor 6 according to an operation command from the operating member, the controller 9 has an emulation model 9a for simulating dynamic characteristics of a hydraulic rotation driving device in real time, and a target value for control is calculated from the emulation model 9a according to the operation command from the operating member to control the electric motor 6. Accordingly, the electric motor can mildly respond to the operation of a lever in an intermediate range and swiftly respond to a quick operation of the lever.

Abstract: First and second hydraulic pumps each adapted to operate plural actuators are activated by separate electric motors respectively. In accordance with signals provided from a controller on the basis of operations of levers, the number of revolutions of the electric motor and that of the electric motor are controlled each independently and simultaneously to control the discharge rates of both hydraulic pumps.

Abstract: A hybrid system working machine, during a normal working time, operated by a normal operation mode that the output of a power generator and the accumulated power of a capacitor are used while the engine is operated over a high-efficiency range at a low output. Switching of a selector switch to a high-speed running mode position and running operation enable long-distance and high-speed running of an increase in engine output by a high-output operation mode.

Abstract: A device, mounted on a hydraulic excavator, for allowing each of first and second electric motors (13), (14) to generate power by using electric power supplied from a power supply having a predetermined capacity, and actuating a boom cylinder (6), an arm cylinder (7), etc. using the generated power. The device is characterized by comprising electric motor controllers (24), (25), etc. for respectively controlling power that is generated by the electric motors (13), (14) so that, in machine-operation, powers generated by the electric motors (13), (14) may be equal to or less than predetermined rated outputs, and that the total amount of powers generated simultaneously by the electric motors (13), (14) may correspond to the maximum capacity of the power supply, so as to prolong the time of use with high thrust and high torque without increasing the capacitors of the electric motors (13), (14) and power supply.

Abstract: A drive apparatus comprises an engine, a hydraulic pump, an electric motor concurrently serving as a generator, a battery, a first control device that charges the battery with the electric power generated by the electric motor concurrently serving as a generator and drives the electric motor concurrently serving as a generator using the electric power of the battery, and a controller. When the input of the hydraulic pump is smaller than the output of the engine, the engine is operated the set number of revolutions and the number of high idle revolutions. And, when the input of the hydraulic pump is larger than the output of the engine, the input of the hydraulic pump is reduced and the electric motor is operated in the electric motor action, whereby the engine output can be supplemented and the engine can be operated in the set number of revolutions.

Abstract: A hybrid construction machine according to the present invention is constructed to drive electric motors (6, 7, 13, 15, 23, 25) by means of power of a power generator (11) to be given by an engine (10), power of an auxiliary battery (42) and power of a main battery (12) charged with power of the power generation (11). The hybrid construction machine has a switch (43) for switching to drive the electric motors (6, 7, 13, 15, 23, 25) by means of power of at least one of the generator (11) and the main battery (12) when operating normally and to drive the electric motors (6, 7, 13, 15, 23, 25) by means of power of the auxiliary battery (42) when operating emergently such that the electric motors (6, 7, 13, 15, 23, 25) can not be driven by means of the normal power.

Abstract: A method for setting a safe work area and a rated load in a swing type work machine, as well as a swing type work machine which utilizes the said method, are disclosed. An area where a strength-based safe work area which is established taking the strength of a swing member into account and a stability-based safe work area which is established taking the stability of the work machine into account overlap each other, is set as a safe work area to be used actually. Likewise, out of a strength-based rated load which is set taking the strength of the swing member into consideration and a stability-based rated load which is set taking the stability of the work machine into consideration, the lower one is set as a rated load to be used actually. Using the safe work area and rated load thus obtained, there are made a safety control and an appropriate display.

Abstract: A rolling mill in which an upper housing is guided upward and downward along columns, a fluid chamber is formed between the upper end section of each column and a column insertion hole of the upper housing; a fixed piston fixedly mounted on the column is fitted in the fluid chamber; a roll gap rapid widening piston is fixedly installed on the upper end of the column, and on this piston is vertically movably fitted a hydraulic cylinder; the hydraulic cylinder is fixedly mounted in the upper housing; pressure fluid is constantly supplied to an upper fluid chamber on the piston; a fluid chamber is provided in the column insertion hole of the upper housing, and a column clamping sleeve is fitted therein; and the pressure fluid is fed into, and discharged out of, the fluid chamber to move the upper housing upward and downward.

Abstract: For use where a hanging load 81 is vertically hung and released with a crane having either a jib or a boom which can be raised or lowered, or where a long hanging load 81 is raised from its lowered state to its vertical state so as to be hung-up and released a control device of the has a control section for performing automatically the raising of the jib 60 or boom 61 and the winding-up or -down of the winding-up rope 70, in cooperation with each other in response to their initial states. In case that the initial angle of the jib or boom is large or small, it is controlled in such a way as a rate of variation of the hanging load .DELTA.T applied to the winding-up rope 70 becomes constant. It positions the extreme end of the jib or boom on the vertical line passing through a center of gravity of the hanging load. With such a control device, the handing load is not oscillated and a smooth vertical releasing is carried out.

Abstract: Herein described is a method and apparatus for controlling braking and stopping of the slewing of an upper slewing body which is slewingably provided on a construction and hoists a load, represented by a rotary crane, wherein the braking torque for braking the upper slewing body and the braking torque for braking a hoisting load are separately obtained by the calculated slewing angular acceleration, and the whole braking torque is calculated on the basis of both the braking torques, thereby achieving a high accurate control of the slewing stop.

Abstract: A method and device is adapted for controlling rotation of an upper rotary body of a construction machine, the upper rotary body being rotatably mounted on a lower body of the construction machine for lifting a load from a predetermined position thereof. The control is executed by determining, based on the radius of rotation of the lifted load, the weight of the lifted load, the inertia moment of the upper rotary body and the permissible weight of the upper rotary body, a permissible condition not to generate a lateral bending force beyond the lateral bending strength of the upper rotary body, and braking the rotation of the upper rotary body at a rotational angular acceleration satisfying the permissible condition and assuring no-swing of the lifted load. A device is adapted for calculating an inclination angle of the upper rotary body.