Kabushiki Kaisha Kobe Seiko Sho

Kobelco Construction Machinery Co., Ltd.

Kobe Steel, Ltd.

Kabushiki Kaisha Kobe Seiko Sho (kobe Steel, Ltd.)

Kabushiki Kaisha Kobe Seiko Sho (kobe Steel, Ltd.) Steel

Hideaki Yoshimatsu

Naoki Sugano

Koji Inoue

Norihiko Hayashi

Koichi Fukushima

Kouichi Fukushima

Masayuki Komiyama

Hideki Kinugawa

Etsujiro Imanishi

Mamoru Uejima

Tetsuo Inoue

Tohru Yoshioka

Akira Nohara

Hiroshi Zui

Masami Hideura

Eiko Hirooka

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.

Rotation brake method and device for working machine

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.

Rotation-type working machine

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.

Rotation control device of working machine

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

Actuator driving device of working machine

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.

Working machine

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.

Construction machinery

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.

Drive device of working machine

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. According to this method, in a swing type work machine such as a crane, it is possible to establish a safe work area and a rated load both matching the actual hoisting capacity of the work machine.

Swing type machine and method for setting a safe work area and a rated load in same

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.

Rolling mill and method for operating rolling mill

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. An entire long hanging load 81 is vertically hung up and released from the ground after its vertical releasing without displacing the position of the other end from its lowered state.

Vertical releasing control device of crane hanging load

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.

Method and apparatus for controlling swing stop of upper swing body in

Method and device for controlling braking of an upper rotary body of a

A safety apparatus which can set an appropriate rated load curve which can be grasped readily by an operator and takes a difference between horizontal extension amounts of outrigger jacks into consideration and can facilitate calculation of a load factor. Entire circumference load calculating means calculates a first rated load regarding a forward and backward direction and calculates a second rated load based on extended conditions of the front and rear outrigger jacks, and then calculates inflection angles of a rated load curve based on the rated loads and the extended conditions of the outrigger jacks, whereafter it sets, from the inflection angles, a final rated load curve which continues over the entire circumference. Further, load factor calculating means calculates a load factor making use of the rated load calculated by the entire circumference load calculating means, and a safety operation is performed in accordance with the load factor.

Safety apparatus for construction equipment

A safety device for a crane which can make a safety operation precisely taking a relationship between a swinging condition of a boom and a limit working region into consideration. In the device, a working radius and a swinging angle of the boom and projection amounts of projectable support members of the crane are detected, and a limit working region of the boom is set in accordance with a weight of a suspended cargo and the projection amounts. A remaining angle over which the boom can be swung until the set limit working region is exceeded is calculated, and also a braking angular acceleration at which swinging movement of the boom is braked and stopped without leaving a shake of the suspended cargo is calculated. Further, a swinging angle of the boom required to brake and stop the swinging movement of the boom at the braking angular acceleration is calculated, and the thus calculated required angle and the remaining angle are compared with each other. Thus, a safety operation is performed before the remaining angle exceeds the required angle. Meanwhile, the set limit working region and a current working radius and swinging angle of the boom are indicated on the same screen of a display unit.

Safety device for crane

A slewing control device for a hydraulic slewing crane adapted to supply a discharge oil from a hydraulic pump through a slewing control valve to a slewing motor and control a rotational direction and a rotational speed of the slewing motor. The slewing control device includes a brake pressure control valve for variably controlling a discharge pressure of the slewing motor, an acceleration pressure control valve for variably controlling a suction pressure of the slewing motor, and a controller for outputting to both pressure control valves a pressure control signal to be determined according to an operational condition of the crane upon braking of a slewing body and controlling both the discharge pressure and the suction pressure of the slewing motor to control a pressure differential therebetween. Accordingly, even when a braking torque is small, the slewing body can be smoothly braked to be stopped at a target position accurately with no oscillation of a suspended load remaining.

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Kobe, Japan

Hideaki Yoshimatsu