Hitachi Construction Machinery Co., Ltd.

Hitachi, Ltd.

Mariko Mizuochi

Akinori Ishii

Hiroshi Sakamoto

Kenji Hiraku

Juri Shimizu

Teppei Saitoh

Jinichi Yamaguchi

Hiroyuki Yamada

Hiromasa Takahashi

Kazushige Kurokami

Kazuyoshi Hanakawa

Shinya Imura

Shiho Izumi

Takehito Ogata

Junya Takahashi

Hiroaki Tanaka

Wataru Tanaka

Yusuke Suzuki

Akira Kanazawa

Keiichi Katsuta

Youhei Toriyama

Hiroyuki Sadamori

Takashi Kusama

Kentaroh Maki

Yamaguchi Jinichi

Ishii Akinori

A site management system manages the positions of workers and work areas of work machines. The workers can recognize the work areas of the work machines at a work site in which the work machines and the workers carry out work. A site management device is connected to a worker terminal carried by a worker and a work machine processor is mounted on a work machine. The site management device generates worker informationon the basis of a signal transmitted from the worker terminal and generates work machine informationbased on a signal transmitted from the work machine processor. Work area informationincluding the position and the work area of a work machine is generated on the basis of the pieces of informationandand a work area notification signal is transmitted with the work area information to the worker terminal device.

Site management system and work machine

The present invention intends to provide a risk management system that can accurately extract information necessary for analysis of a variety of accidents in which a machine is involved. For this purpose, a controller calculates a main risk that is the degree at which a main factor of an accident contributes to the occurrence of the accident on the basis of an evaluation value of the main factor, and calculates a subsidiary risk that is the degree at which a subsidiary factor of the accident contributes to the occurrence of the accident on the basis of an evaluation value of the subsidiary factor. Furthermore, the controller calculates, as the occurrence risk of the accident, an integrated risk that has a value equal to or larger than the main risk and increases or decreases at a degree lower than the degree of increase or decrease in the subsidiary risk, and, when the integrated risk has exceeded a predetermined threshold, causes a recording device to record parameters measured by measuring devices in a certain time period including a clock time at which the integrated risk has exceeded the predetermined threshold.

Risk management system

In a traffic flow control system, communication is performed with a travel control device of a moving body passing through a transportation route and the traffic flow of the transportation route is controlled. The traffic control system includes an entry authority management unit and a communication unit. In a transportation route divided into virtual areas, the entry authority management unit manages entry authority for each area, managing tokens in a number that corresponds to the area, and guiding entry of the moving body to the area by attaching entry authority to a token and delivering the resulting token to the travel control device. The communication unit communicates the entry authority and tokens to the travel control device.

Traffic flow control system, traffic flow control program, traffic flow control method, and traveling controller

Provided is a work machine that, within the limit of not harming dynamic stability, can perform work utilizing the impact generated when a cylinder driving a front work implement collides with a stroke end. A drive control systemincludes: a stroke end distance calculation and evaluation sectionthat determines whether or not it is possible for cylindersA andA to collide with a stroke end; a dynamic center of gravity position prediction sectionthat, when the stroke end distance calculation and evaluation section determines that it is possible for the cylinders to collided on the stroke end, predicts a trajectory of the dynamic center of gravity position of a hydraulic excavatorfrom a time when a decelerating operation of the cylinder starts to a time when the cylinder stops; and an allowable velocity changing sectionthat changes the allowable velocity of the cylinder according to a minimum distance from the trajectory of the dynamic center of gravity position predicted by the dynamic center of gravity position prediction section to a tipping line of the hydraulic excavator.

Work machine

An operator of a hydraulic excavator and a worker working outside of the hydraulic excavator carry a worker tag that sends a radio-wave signal including a magnetic field ID, a tag ID, and positional information obtained by a GNSS receiving section in case the worker tag receives a magnetic field signal generated by a magnetic field detecting device mounted on the hydraulic excavator. Based on positional information of the hydraulic excavator that is obtained from an GNSS receiving device and positional information of the worker tag, the position of the worker tag is calculated. In case the worker tag is detected in a proximity notification target area, a notification command is generated for notifying the operator of the hydraulic excavator of the detection of the worker tag, and output to a notification device in the cabin of the hydraulic excavator. Thus, a worker who is in proximity to the work machine is accurately detected, and the operator is prevented from being excessively alerted.

In a worker management system comprising a terminal device, a worker detection system, and a site management device, the terminal device transmits a worker signal, which includes terminal GNSS positional information represented by a GNSS coordinate system of the terminal device, to the site management device. The worker detection system transmits worker detected positional information, which indicates a position of the worker detected by a surrounding monitoring sensor mounted on the work machine, to the site management device. The site management device relates the terminal GNSS positional information to the worker detected positional information, and when both information for the same worker is available, it selects a position indicated by the worker detected positional information, and when only the terminal GNSS positional information is available, it selects a position indicated by the terminal GNSS positional information, as a current position of the worker.

Worker management system

Provided is a controller () that includes a mechanical state acquisition section () that acquires information regarding a posture and an operation of a hydraulic excavator; a blind angle calculation section () that calculates a blind angle area from a seat in a cab () of the hydraulic excavator based on the information indicating the posture and the operation of the hydraulic excavator and acquired by the mechanical state acquisition section (); and a visibility level determination section () that determines a visibility level of an obstacle based on the blind angle area calculated by the blind angle calculation section () and a positional relationship calculated by a position relation calculation section (). Further, a warning level determination section () of the controller () adjusts a warning level in accordance with the visibility level determined by the visibility level determination section ().

Periphery monitoring device of work machine

A drive control system for a work machine. A gradual stoppage command and an operation speed limitation command are calculated and output. A pilot pressure is corrected such that, upon a stoppage operation of a control lever, a drive actuator is stopped gradually; and the pilot pressure is corrected such that an operation speed of the drive actuator is limited. A supply of the pilot hydraulic fluid to the speed increasing unit is interrupted when a failure of a speed increasing solenoid proportional valve of the speed increasing unit is detected.

Drive control system for work machine

The work machine includes a stabilization control calculation unit that calculates and outputs a gradual stoppage command for making a drive actuator stop gradually and an operation speed limitation command for limiting an upper limit operation speed according to the status of stability of the work machine, a stoppage characteristic modification unit that corrects pilot pressure so as to make the drive actuator stop gradually when a stoppage operation is performed on a control lever, and an operation speed limitation unit that corrects the pilot pressure so as to limit the operation speed of the drive actuator.

To provide a hydraulic driving device configured to smoothly extend a hydraulic cylinder. The present invention includes the open circuit E, the closed circuit A, a control device, and a control lever. The open circuit E is provided with a flow passagefor connecting an outlet port of the open circuit pumpand a head chamberof the boom cylinder, a selector valveprovided in the flow passage, a discharge flow passagefor connecting a hydraulic fluid tankand a flow passage, and a bleed-off valveprovided in the discharge flow passage. The control deviceis configured in such a manner that when a manipulate signal for extending the boom cylinderis input from the control lever, the bleed-off valveis closed, the selector valveis subsequently opened, and the open circuit pumpis controlled.

Hydraulic driving system

There is provided a driving device for a work machine, having a closed hydraulic circuit system for driving cylinders with hydraulic pumps, the driving device making the speed of operation substantially the same in both directions of piston rod extension and contraction. The driving device includes: a first hydraulic pump that has flow rate control device for controlling the flow rate and direction of hydraulic fluid to be delivered; a single rod hydraulic cylinder that is driven with the hydraulic fluid to drive one of work members of a work device on the work machine; a closed hydraulic circuit that connects the first hydraulic pump with the single rod hydraulic cylinder to form a closed circuit using flow lines through which the hydraulic fluid flows; a branch line that branches from the flow line between the first hydraulic pump and the single rod hydraulic cylinder; a first flow line of which one end is connected to the branch line; a tank to which the other end of the first flow line is connected; and a hydraulic fluid flow rate control device attached to the first flow line to control the flow rate of the hydraulic fluid flowing from the branch line to the tank or from the tank to the branch line.

Driving device for work machine and work machine equipped therewith

To provide a driving device capable of improving the operability of a plurality of single rod hydraulic cylinders. The present invention takes a construction provided with a closed circuit A in which first and third hydraulic pumpsand a boom cylinderare connected through selector valvesin a closed-circuit fashion, a plurality of open circuits E, F provided with second and fourth hydraulic pumpsand selector valvesthat switch the supply destinations of hydraulic oils flowing out from the second and fourth hydraulic pumps, and a connection passageconnected to sides of the selector valvesfrom which sides hydraulic oil flows out, and connected to the closed circuit A.

Driving device for work machine

A hydraulic closed circuit system using a single rod type hydraulic cylinder prevents the hunting of a flushing valve due to a delay in response of the flushing valve and circuit pressure pulsations, thereby preventing a decrease in operability of the hydraulic cylinder. A single rod type hydraulic cylinder is connected to a hydraulic pump via two hydraulic lines. A flushing valve is connected between the hydraulic lines and a tank; and a control unit is configured to add a predetermined control parameter to a pressure in a lower-pressure hydraulic line of the two hydraulic lines. The magnitude of a pressure in the higher-pressure hydraulic line of the two hydraulic lines is compared with the magnitude of a compensation pressure to which the control parameter has been added, and the flushing valve is switched when the compensation pressure and the higher-pressure hydraulic line pressure are found to be reversed in magnitude.

Hydraulic closed circuit system

A load detecting device that can highly accurately detect the magnitude and direction of a load whose direction of action changes regardless of the dimension of a pin is provided. Also, a working machine that is provided with this load detecting device and allows work to be performed safely and highly efficiently is provided. The load detecting device is configured with a pin-type load celland a load calculating unit. The pin-type load cellis provided with three pairs of or three strain detecting units that are placed in the circumferential direction of the pin body. The load calculating unitselects, from among the three or more pairs of or three or more strain detecting units, two pairs of or two strain detecting units that are less influenced by a change in the cross-sectional shape of the pin body, and calculates a load that acts on the pin bodyaccording to an output of these selected strain detecting units.

Load detecting device and working machine provided with same

To provide a work machine with high stability in which a dynamic balance can be evaluated easily while the influence of a sudden stop of an travel base, an upperstructure and a work front is taken into consideration. A stabilization control calculation unit () and a command value generating unit () are provided in a control device () of the work machine. The stabilization control calculation unit () uses a sudden stop model and position information of each movable portion of the travel base and a machine body including the work front () to predict a change of stability until reaching a complete stop when a control lever () in an operating state is instantaneously brought back to a stop command position, and calculates a motion limit needed to prevent destabilization from occurring at any time instant until reaching the stop. The command value generating unit () corrects the command information to a drive actuator on the basis of the calculation result of the stabilization control calculation unit ().

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Hitachinaka, Japan

Mariko Mizuochi