Hitachi Construction Machinery Co., Ltd.

Hitachi, Ltd.

Kichio Nakajima

Kazuo Honma

Eiki Izumi

Hiroshi Watanabe

Yukio Aoyagi

Tomohiko Yasuda

Hiroshi Yamamoto

Akira Kikuchi

Shinjiro Saito

Taro Iwamoto

Toshikazu Minoshima

Tatsu Aoki

Hiroyuki Kobayashi

Taichiro Yamashita

Junichi Tamamoto

Takayuki Sato

Akira Tsuchihashi

Shinichi Takarada

Yukio Sumiya

Hiroaki Tokairin

Yasuo Tanaka

Motoo Futami

Takashi Ikimi

Takashi Yoshida

Kazushi Yoshida

Shunichi Oohara

Takashi Yagyu

Yutaka Watanabe

Takayuki Satou

Keizo Shimada

Toshihiko Tajiri

Takeshi Yamaguchi

Yuko Okada

Kiyoshi Nagasawa

Junji Fujita

Hiroshi Inamitsu

Eiji Minamiyama

Katsuro Abe

Takeshi Aritake

Masaaki Uno

A vehicle control device, a controller, an inverter control deviceand a steering control deviceconstitute a control device that executes control to give a yaw moment to a vehicleso as to make the vehicletravel while meandering around the center of trolley wiresR andL based on image information acquired by a camera. The control device converts an image acquired by the camerainto coordinate information, calculates at least one representative point of the vehicleand at least one target point situated on the trolley wireR/L based on the coordinate information, sets a fluctuating point which fluctuates with reference to the target point, and executes control to give a yaw moment to the vehicleso that the representative point approaches the fluctuating point. With this configuration, uneven wear of the sliders can be prevented and the operating load on the driver during the trolley traveling can be lightened considerably.

Electrically driven dump truck

A control device which executes the following control based on image information acquired by a camera: When the vehicle is traveling outside a trolley wire linkage section C, the control device executes control to give a yaw moment to the vehicle so that the vehicle travels while tracing a trolley wireR/L. When the vehicle is traveling in the trolley wire linkage section C, the control device performs control not to execute the control to give the yaw moment. Further, the control device converts the acquired image information into coordinate information. Based on the coordinate information, when the vehicle is traveling outside the trolley wire linkage section C, the control device calculates a representative point of the vehicle and a target point situated on the trolley wireR/L and gives a yaw moment to the vehicle so that the representative point approaches the target point.

Provided is an electrically driven vehicle that is capable of suppressing drive wheel slippage without increasing the pitching vibration of the vehicle. The electrically driven vehicle having electric motors (), drive wheels () driven by the electric motors respectively, and, when at least one of the drive wheels slips, an electric motor control device () for reducing the torque of at least one of the electric motors that drives the at least one wheel slipped, and for restoring the torque of the at least one electric motor when the slippage is stopped includes a pitching detection device () for detecting the amplitude of pitching vibration to which the vehicle is subjected. The amount of torque of the at least one electric motor to be restored by the electric motor control device over a predetermined period of time after the slippage is stopped varies depending on whether or not the amplitude A detected by the pitching detection device is greater than an assessment value A

Electrically driven vehicle

A vehicle control device, a controller, an inverter control deviceand a steering control deviceconstitute a control devicewhich controls elevation of slidersRa andLa of power collectorsR andL based on information detected by a trolley wire detecting device (camera). The control devicecalculates positional relationship between a slider and a trolley wireR/L based on the information detected by the trolley wire detecting device. When the slider has deviated from a prescribed range for being in contact with the trolley wire, the control device executes control to prohibit an operation for elevating the sliders or to lower the sliders when the sliders have been elevated. With this configuration, an electrically driven dump truck capable of lightening the operating load on the driver during the trolley traveling is provided.

A vehicle control device, a controller, an inverter control deviceand a steering control deviceconstitute a control devicewhich executes control to give a yaw moment to a vehicleto make the vehicletravel while tracing a trolley wireR,L based on image information detected by a camera. The control deviceconverts an image acquired by the camerainto coordinate information, calculates at least one representative point of the vehicleand at least one target point situated on the trolley wireR,L based on the coordinate information, and executes the control to give a yaw moment to the vehicleso that the representative point approaches the target point. With this configuration, an electrically driven dump truck capable of lightening the operating load on the driver during the trolley traveling is provided.

Wheel drive motors () constituted of electric motors for driving rear wheels () are provided on a vehicle body () of a dump truck (). Each wheel drive motor () is connected to a main power generator () through a bidirectional converter () and the like and driven by power supplied from the main power generator (). A resistor () that consumes regenerative power from each wheel drive motor () is connected to the bidirectional converter (). Cooling air is supplied to the resistor () from a blower (). Operations of a switch () of the resistor () and the blower () are controlled by a controller (). A mode selecting switch () for selecting a heating mode (A), a blowing mode (B), and a heating and blowing mode (C) is connected to the controller ().

Electric working vehicle

An electrically driven vehicle equipped with electric motors () for driving or braking drive wheels (), and an electric motor controller () for controlling the electric motors includes: wheel speed detectors (to) for detecting the wheel speed of the drive wheels and that of idler wheels (); computing means (toto) for computing the slip ratio of the drive wheels based on the wheel speed of the drive wheels and that of the idler wheels; and a determiner () for determining that the drive wheels are slipping if the slip ratio exceeds a slip ratio determination value. If the wheel speed of the idler wheels is lower than set speeds Va, Vb, then the determiner () changes the slip ratio determination value to a value having as the same sign as, and a larger absolute value than, the values &#x3bb;a, &#x3bb;bused when the wheel speed of the idler wheels is higher than the set speeds Va, Vb. This structure shortens acceleration time during acceleration traveling and reduces braking distance during deceleration traveling while inhibiting vibrations of the electrically driven vehicle.

A vehicle which evaluates tire wear properly even in a road condition that tires easily slip or lock up. The vehicle, which has a driven wheel and a driving wheel with tires attached thereto, includes: a revolution speed detector for detecting revolution speeds of the driven and driving wheels; a wheel speed detector for detecting wheel speeds of the driven and driving wheels based on the detected revolution speed data of the driven and driving wheels; a wheel speed ratio detector for detecting a wheel speed ratio between the driven and driving wheels based on the detected wheel speed data of the driven and driving wheels; and a tire condition evaluator for outputting an evaluation result indicating that the tire(s) attached to the driven wheel and/or driving wheel is(are) worn when the wheel speed ratio is higher than a preset threshold.

Vehicle having tire wear evaluation system

Engine driving characteristics are achieved for driving a hydraulic system during non-traveling and traveling in an electrically driven dump truck. When a shift leveris located at a neutral position, the target revolution speed Nrcorresponding to the operation amount (p) of an accelerator pedalis calculated on the basis of first target revolution speed characteristics (Nr()) which are suitable for driving of a hydraulic pump for working so that an electronic governoris controlled on the basis of this target revolution speed. When the shift leveris located at a forward position, the target revolution speed Nrcorresponding to the operation amount of the accelerator pedalis calculated on the basis of second target revolution speed characteristics (Nr()) which are suitable for driving of electric motorsR,L so that the electronic governoris controlled on the basis of this target revolution speed.

Drive system for electrically driven dump truck

An electric drive vehicle having a power generator coupled to an engine, a first power converter connected with the power generator for converting the AC power generated by the power generator to DC power, a second power converter connected with the first power converter, for converting the DC power to AC power, a power consuming device for consuming the DC power, connected to a DC circuit between the first and second power converters, an electric motor connected with the second power converter, and at least one wheel driven by the electric motor, wherein the vehicle has a first control mode for controlling the output of the electric motor and a second control mode for controlling the power consumed by the power consuming device, and the second control mode performs such control that the operations of the second power converter and the electric motor in the first control mode are simulated.

Electric drive vehicle

A paper sheet sorting apparatus comprising a device for reading the information recorded in paper sheets and a device for sorting the paper sheets in accordance with the information thus read, is disclosed. The load of recognizing the information is detected by a load detector. In accordance with the load detected by the load detector, the interval between the paper sheets supplied or the speed at which the paper sheets are transported is changed. In this way, the interval of the papers sheets entering the reading device is changed. The number of paper sheets having the information that cannot be recognized and hence cannot be sorted is reduced, while at the same time improving the processing speed.

Paper sheet sorting apparatus and sorting method

A paper sorting apparatus includes first to fourth gap measuring units to measure gaps between sheets of paper. Using the gaps between the sheets varying between the respective gap measuring units, target gap correction values are stored for respective sort shelves. In accordance with gaps between sheets changed between the first and second gap measuring units, there are predicted gap variations possibly taking place by when the sheets reach the associated sort shelves. Depending on the predicted gap variations, a gap adjuster is controlled to set the gaps to appropriate values at a point where the pertinent sheets reach the associated sort shelves.

Inter-article gap adjustor for controlled delivery to a sorting device

Ultrasonic flaw detector

A stereoscopic imaging system enabling observation of a stereoscopic image due to parallax by reproducing, on a single screen in an image-reproducing means two kinds of images of an object which are taken by two imaging units and between which there is parallax and by observing the images in such a manner that the left and right eyes of the observer observe only the separate images taken by the separate imaging units corresponding to the left and right eyes, wherein there is provided swing means for mechanically or electronically shifting the optical axes of the respective lenses of said two imaging units, by which swing means the observer can view a stereoscopic image without fatigue and in a natural condition.

Stereoscopic imaging system

A master slave manipulator system includes a master arm having six or more axes of motion and an articulated slave arm having six or more axes of motion and being shaped in sharp contrast with the master arm. The master arm has an arm body with three axes perpendicular to each other and a wrist assembly connected to the arm body. The wrist assembly has a gripper disposed in a space of a size large enough for an operator to operate the gripper with his clutched hand in X, Y and Z directions and also has a pitch-axis, a yaw-axis and a roll-axis all disposed outside of the space. The pitch-axis, yaw-axis and roll-axis have output axes directed toward the gripper. The slave arm has an arm body with axes longitudinally stretchable or foldable into parallel positions, and a wrist assembly having three axes disposed in a space of predetermined dimensions in X, Y and Z directions. The output axes of the three axes of the slave arm wrist assembly are directed away from the mounting portions of these axes. The slave arm is so controlled as to follow movements of the master arm.

Growing community of inventors

Ibaraki, Japan

Kichio Nakajima