Hitachi Construction Machinery Co., Ltd.

Hitachi, Ltd.

Hitachi Power Solutions Co., Ltd.

Tomohiko Yasuda

Takayuki Sato

Masanori Ichinose

Akira Kikuchi

Takashi Yagyu

Takayuki Satou

Yasuo Tanaka

Kichio Nakajima

Yukio Aoyagi

Yutaka Watanabe

Atsushi Kitaguchi

Kazunori Ishihara

Michio Fushiki

Yoshifumi Nabeshima

Yasuki Kita

Takehito Ikema

Takashi Sasaki

Hitomi Ooshima

Hiroyuki Kobayashi

Satoru Kaneko

Shinjiro Saito

Wataru Tanaka

Toshikazu Minoshima

Shuichi Ichiyama

Motoo Futami

Takashi Ikimi

Kazuhiro Imaie

Keizo Shimada

Shinji Akino

Jun Ikeda

Takashi Yagyuu

Hirokazu Shimomura

Hajimu Kozawa

Hiroyuki Kanazawa

Keiichiro Uno

Atsushi Nakajima

Takeo Yamamoto

An operation management system obviates such a situation that a power substation would trip and a supply of power to overhead wires would stop. The operation management system controls operation of electric drive vehicles, each of which is provided with a trolley mode, in which the electric drive vehicle runs by power supplied to the overhead wires, and a diesel mode, in which the electric drive vehicle runs by an output from an engine. A supply margin detection unit detects a current supply margin of power and a running position detecting unit detects a current running position of the electric drive vehicle. A running mode detection unit detects a current running mode of the electric drive vehicle and a running mode determination unit determines a next running mode based on the detection results of the supply margin detection unit, running position detecting unit, and running mode detection unit.

Operation management system

A trolley-type truck is provided with a pantograph and travels in a trolley mode under electric power from an overhead wire and a non-trolley mode without obtaining electric power. The pantograph has a base frame, a bottom frame and a top frame rockably attached to the base frame, and a collector shoe supported by the top end portion of the top frame. A fixing member is disposed on the top end side of the top frame for fixing the pantograph, a hook device is disposed on the base frame, and a hook receiver is disposed on the base frame in order to receive the fixing member. When a frame assembly formed of the bottom frame and the top frame is folded, the fixing member becomes seated in the hook receiver and is pressed by means of the hook device, thereby securely fixing the frame assembly to the base frame.

Trolley-type truck

Provided is an electric drive vehicle which can control wheel speed so as to achieve an appropriate slip ratio of the wheels even when pitching vibration of the vehicle is large. This electric drive vehicle is provided with electric motors (), drive wheels (), driven wheels (), an electric motor controller () for controlling the electric motors, and speed detectors (-) for detecting the wheel speed of the drive wheels and the driven wheels. The electric motor controller is provided with: a slip ratio calculation unit () which calculates the slip ratio of the drive wheels from the wheel speed detected values detected by the speed detectors; a torque command calculation unit () which calculates torque commands for the drive wheels; a drive force calculation unit () which, from the wheel speed detected values of the drive wheels and the torque commands of the drive wheels, calculates the drive force generated in the drive wheels; and filters () which reduce the pitching vibration frequency components of the vehicle included in the slip ratio and the drive force.

Electric drive vehicle

A mining vehicle is provided, which is capable of appropriately recognizing a condition of a traveling road in front of the vehicle, preventing an obstacle on a roadside from being erroneously detected by a distance detector, and controlling the speed of the vehicle in a stable manner even when the vehicle is approaching a curved portion of the road from a linear portion of the road. The mining vehicle that travels on a transport road of a mining site includes: a minimum roadside distance determining unit; a traveling status calculator configured to calculate traveling status of the vehicle and a turning radius of the vehicle; a roadside distance calculator configured to calculate a roadside distance between the vehicle and a roadside of the transport road; a roadside distance selector configured to select and output a minimum roadside distance if the vehicle is in a rectilinearly traveling state and select and output the roadside distance calculated with the roadside distance calculator if the vehicle is in a turning state; a detected distance limiter configured to disable a signal representing the distance, detected with the distance detector, between the vehicle and the object and the relative speed if the distance between the vehicle and the object is larger than a distance represented by a signal selected and output from the roadside distance selector; and a vehicle speed controller configured to control the speed of the vehicle on the basis of a signal output from the detected distance limiter.

Mining vehicle

Disclosed is a body structure for a dump truck () having a body frame (). The body structure is provided with hinge pins () to be located toward a rear of the body frame, a body (A) to be tiltably disposed on the body frame via the hinge pins and to be adapted to load payload (), and stiffening members arranged on outer surfaces of the body. The body is constructed at least of a floor board (), a front board (), side boards (), and a canopy (). The stiffening members include side-board stiffeners () connecting upper portions of elongated joints between the side boards and the front board to portions of elongated joints between the side boards and the floor board. The latter portions are located rearward of positions laterally corresponding to a barycentric position (G) of the payload () in a longitudinal direction of the body.

Body structure for dump truck

Disclosed is a driving force control device that includes a determination section (), a driving force command value calculation section (), and a command value output section (). The determination section () determines whether each of a plurality of motors (), which independently drive a plurality of wheels (), can be operated within a desired operating range when driven by a target driving force calculated for each of the motors (). The driving force command value calculation section () adjusts the distribution of driving force for each of the motors in accordance with the target driving force for each of the motors and with the operating status of each of the motors and calculates an actual driving force command value for each of the motors for the purpose of operating each of the motors within the desired operating range if the determination means determines that each of the motors cannot be operated within the desired operating range. The command value output section () outputs the driving force command value to each of a plurality of inverters (). Therefore, a target vehicle motion can be maximally realized while appropriately maintaining the drive status of each of the motors.

Driving force control device for electric vehicle

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 dump truck parking position/direction indication system and a hauling system are provided that allow the operator of a loading machine to determine a parking position and a parking direction of a dump truck. The dump truck parking position/direction indication system includes: a bucket position detection device which detects the position of a bucket of the loading machine; a locus calculation device which calculates a movement locus of the bucket based on the positions of the bucket detected by the bucket position detection device; a parking position/direction determination device which determines the parking position and the parking direction of the dump truck based on the movement locus calculated by the locus calculation device; and an output device which outputs the parking position and the parking direction of the dump truck determined by the parking position/direction determination device.

System for indicating parking position and direction of dump truck and hauling system

A dump vehicle overturn preventing device includes: a loaded weight estimation unit which estimates loaded weight on the body; a vehicle rotation moment calculation unit which calculates a vehicle rotation moment Mb caused by movement of the dump vehicle's load upon discharging of the load; a reference moment calculation unit which determines a reference moment Ms not greater than an overturn threshold moment MI which is the minimum value of a rotation moment required to lift the front wheels off the ground; a judgment unit which judges whether or not the vehicle rotation moment Mb has exceeded the reference moment Ms; and a display device which notifies the driver that there is a probability of an overturn of the vehicle when the vehicle rotation moment Mb is judged to have exceeded the reference moment Ms.

Dump vehicle overturn preventing device

A body for a dump truck includes a body frame, a bottom wall, front wall, and left and right side walls arranged on the body frame. The body also includes an earth/sand anti-sticking device and a steel member arranged outside and opposite the earth/sand anti-sticking device such that a space is formed between the steel member and the earth/sand anti-sticking device. The body is provided with at least one steel rib arranged in the space, fixedly secured to the steel member to reinforce the steel member, and arranged extending upright toward the earth/sand anti-sticking device. The steel member is any one of the bottom wall, front wall, and left and right walls, and the steel rib is shaped to divide the space.

Body for dump truck

A body for a dump truck includes a body frame, a bottom wall, front wall and left and right side walls arranged on the body frame. The bottom wall, front wall and left and right side walls define a payload section for loading a payload, an earth/sand anti-sticking device is arranged in a corner part of the payload section to prevent earth or sand from sticking in the corner part. A steel member is arranged outside and opposite to the earth/sand anti-sticking device such that a space is formed between the steel member and the earth/sand anti-sticking device. The body includes at least one steel rib having a ridge extending out from a surface of a plate that forms the earth/sand anti-sticking device, the ridge is fixedly secured by welding to the plate that forms the earth/sand anti-sticking device.

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.

To suppress a change in a vehicle's attitude due to a pitch motion during vehicle braking, a pitch control device for an electric vehicle can prevent discontinuous negative acceleration from occurring at a moment of the vehicle stopping by appropriately controlling a braking force of the vehicle, thereby effectively controlling the pitch motion of the vehicle, and can enhance steering stability while ensuring riding comfort for passengers, even when traveling resistance significantly changes according to road surface gradient and when the vehicle weight significantly changes with increases/decreases in the number of drivers and in the quantity of goods loaded. This pitch control device for an electric vehicle, configured to conduct pitch control for suppressing the change in the attitude of the vehicle due to the pitch motion of the electric vehicle, controls the vehicle so that a braking/driving torque command value that is output to a motor for driving the vehicle when the vehicle stops will be a traveling resistance equivalent torque that is a value obtained by converting a force needed to stop the vehicle on a sloped road surface and maintain the vehicle in a stopped condition, into a torque of the driving motor.

Pitch control device for electric vehicle

An electric vehicle includes a pitching state quantity detector for detecting quantity of a pitching-motion of the vehicle, a vehicle weight determiner, a pitching target quantity calculator for calculating a target quantity of a pitching motion at least from the determined vehicle weight, and a torque correction calculator for increasing/reducing a driving torque output, according to a particular differential between the detected pitching-motion state quantity and the calculated target quantity.

Electric vehicle with pitch control device

Rear wheel tires of a vehicle body are spaced apart from each other in the vehicle width direction. A foreign object removing device is provided between an outer tire and an inner tire of the rear wheels on one side of the vehicle for removing foreign objects between the tires. The foreign object removing device includes a bar-shaped member inserted in a suspended state between the tires, and a shoe provided in a lower end side of the bar-shaped member to collide with foreign objects such as earth and sand, and stones getting in between the tires for flicking out the foreign objects from between the tires. The shoe is replaceably attached to the lower end side of the bar-shaped member by using a bolt. In a case where the shoe wears down, only the shoe is replaced.

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Kashiwa, Japan

Tomohiko Yasuda