Hitachi Construction Machinery Co., Ltd.

Takayuki Sato

Tomohiko Yasuda

Masanori Ichinose

Akira Kikuchi

Hidefumi Ishimoto

Takaaki Tanaka

Hiroyuki Kobayashi

Kichio Nakajima

Shinjiro Saito

Wataru Tanaka

Mikio Bando

Yasutaka Tsuruga

Motoo Futami

Masatsugu Arai

Takuya Naka

Toshikazu Minoshima

Naoki Fukuda

Takanobu Ikari

Atsushi Kitaguchi

Kazunori Ishihara

Yukihiko Ono

Michio Fushiki

Shinji Akino

Yoshifumi Nabeshima

Yasuki Kita

Jun Ikeda

Takashi Sasaki

Takehito Ikema

Ryuji Kouno

Takeo Yamamoto

An automatic brake subsystem () includes second accumulators (F,R), a front second line () and a rear second line (), second brake valves (F,R), a first solenoid switching valve (), first shuttle valves (F,R), and a controller. A second solenoid switching valve (F) and a pressure sensor (F) are provided in the front second line (), and a second solenoid switching valve (R) and a pressure sensor (R) are provided in the rear second line (). In a case where it is determined that each of the second brake valve (F,R) is not performing normally based upon a pressure of a hydraulic fluid detected by each of the pressure sensors (F,R) and an operating signal supplied to the first solenoid switching valve () or each of the second brake valves (F,R), a controllerperforms control to switch each of the second solenoid switching valves (F,R).

Brake system

A hydraulic drive fan control device is provided with a variable displacement hydraulic pump, a hydraulic motor, a hydraulic drive fan that is driven by the hydraulic motor, a flow amount control valve, a rotational speed detector that detects a rotational speed of an engine, and a controller. The controller outputs a first valve control signal to the flow amount control valve and outputs a first pump control signal to the hydraulic pump to rotate the hydraulic drive fan at a first rotational speed, and outputs a second valve control signal to the flow amount control valve and outputs a second pump control signal to the hydraulic pump, thereby stopping the rotation of the hydraulic drive fan.

Hydraulic drive fan control device

An autonomous traveling vehicle, equipped with autonomous traveling function on a standard machine, has a high-pressure selector valve placed on a flow path in which pressure-oil is supplied from a standard brake valve (SBV) installed in the standard machine to a hydraulic brake. A flow path is installed to connect the high-pressure selector valve and an autonomous brake control valve (ABCV) that is supplied with pressure-oil delivered by a hydraulic pump. Further, an autonomous traveling controller is installed to perform control for autonomous travel, and an autonomous brake controller is installed to perform open or close control on the ABCV in response to a braking instruction from the autonomous traveling controller. When the brake pedal is stepped on, the pressure-oil flows from the SBV to the hydraulic brake, and when the autonomous traveling controller outputs a stop instruction, the pressure-oil flows from the ABCV to the hydraulic brake.

Work machine and braking method for work machine

An obstacle monitoring device includes a first object detecting section which detects a relative position of a first object located ahead in a moving direction of a vehicle, based on output data of a first moving-direction monitoring sensor, a second object detecting section which detects a relative position and profile of a second object, based on output data of a second moving-direction monitoring sensor which has a higher spatial resolution than the first moving-direction monitoring sensor, an interference determination section that determines whether the vehicle will interfere with the first object and also determines identity between the first object and the second object, and a profile determination section that, if the interference determination section has determined that the first object and the second object are identical to each other, determines whether the profile of the second object will allow the vehicle to pass over the second object.

Obstacle monitoring device, vehicle control device and work machine

A relative position calculating system for work machines includes a first dump truck () which receives a navigation signal from at least one of a plurality of satellites (), a second dump truck () which receives a navigation signal from at least one of the plurality of satellites (), and a relative position calculating apparatus () which calculates a relative position between the first dump truck () and the second dump truck () based on the navigation signals which the first dump truck () and the second dump truck () receive, respectively, from a common satellite of the plurality of satellites (). Thus, an influence of a positioning error due to a satellite positioning system is reduced, and accuracy of a calculation for the relative position between the two dump trucks () can be enhanced.

Relative position calculating system for work machine

A dump truck includes a plurality of rear wheels () rotatably attached to a frame () and two GPS receivers () arranged to be dislocated from each other in an anteroposterior direction of a vehicle. Any point selected from an area C, in the vehicle coordinates system B set in the dump truck, where the rear wheels contact a ground is defined as a reference point D. The two GPS receivers are arranged so that a vertical line descends from a line segment PQ, connecting two points P, Q of which positions are calculated by the two GPS receivers, to the reference point D. This makes it possible to accurately estimate an attitude of mining machinery by two position estimation means without stopping operation of the machinery.

Dump truck

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

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

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

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.

Transporter vehicle

Provided is an overturn preventing device for a dump vehicle equipped with a body () and hoist cylinders (). The dump vehicle overturn preventing device comprises: 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. The device thus prevents overturning of the vehicle caused by the load sliding down from the body in a lump.

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Kashiwa, Japan

Takayuki Sato