Abstract: Hardened surface layers (12) and (14) of a nitride or other compound, which is higher in hardness than dirt or soil, are formed on the inner peripheral surface (11B) of each metal bush (11) and on the outer peripheral surface (13A) of each connecting pin (13) which constitute a crawler belt (7), respectively. In addition, resinous sliding bearings (15) are fitted in transversely spaced positions on the inner periphery of each metal bush (11) of the crawler belt. Bearing (15) is provided with recessed grooves (16). Accordingly, part of soil or dirt which intrudes into a gap space between an outer link portion (9) of a track link and a metal bush (11) through an annular seal member (17) is trapped on an inner peripheral surface (15A) of the bearing (15).

Abstract: Provided are hydraulic pumps 1,2, a control valve group 15a connected to the pump 1 and including a bypass on/off valve 7, a control valve group 15b connected to the pump 2 and including a reserve-actuator-controlling, directional control valve 11, a communication line 13 communicating a most upstream side of the control valve group 15a with a supply line 11a to the reserve-actuator-controlling, directional control valve 11, a merge control valve 14 for communicating or cutting off the communication line 13, an interlocked control means for changing over the merge control valve 14 to an open position and the bypass on/off valve 7 to a closed position in association with a change-over operation of the reserve-actuator-controlling, directional control valve 11, and a selective control valve 28 capable of taking one of a state, in which the operation to change over the merge control valve 14 by the interlocked control means is feasible, and another state in which the operation to change over the merge control va

Abstract: A construction machine management system includes a receiver provided at a remote location from a plurality of construction machines, which receives information related to the lengths of operating time of the construction machines individually transmitted from the construction machines and a decision-making device that makes a decision as to whether or not there is any over-operated construction machine based upon the operating time information that has been received.

Abstract: A construction machine refueling system receives information transmitted from a construction machine at a receiver provided in a base station, and the construction machine includes a detector that detects a residual fuel amount and a transmitter that, when the residual amount of fuel is less than a specified value, transmits information indicating that fact to the base station.

Abstract: This system is comprised of a hydraulic excavator 1 and a base station 16. The hydraulic excavator 1 is deployed at a construction site and is provided with a rewritable memory 402 storing control programs and/or data required for control of the machinery, a CPU 401 for reading out the control programs etc. from the memory 402 and executing them, and a communications device 42. The base station 16 is provided with a communications device 16a, a management server 17 for identifying the serial number of the hydraulic excavator and transferring information with the control unit, and a database 18 managed by the management server 17 and storing control programs etc. corresponding to the hydraulic excavator such as control programs for each model of the hydraulic excavator. When changing or switching the attachment etc. at the hydraulic excavator etc.

Abstract: A security system for a construction machine including a construction machine equipped with a body controller for storing a first password, management apparatus arranged in a location apart from the construction machine and a portable communications unit for storing a second password provided communicably with the management apparatus and the body controller. The portable communications unit, receiving the first password from the management apparatus, replaces the second password with the first password. The body controller determines whether the second password output from the portable communications unit coincides with the first password. In case these passwords coincide with each other, an engine drive signal is output. Otherwise the engine is kept inoperable. This prevents possible theft of a construction machine.

Abstract: A construction machine rental fee setting system comprises a receiver, provided at a location remote from a construction machine, that receives information relating to the usage conditions and/or the usage environment of the construction machine transmitted from the construction machine, and a rental fee setting device that sets a construction machine rental fee based on the information received at the receiver.

Abstract: A working time for each of an engine 32, a front 15, a swing body 13, and a travel body 12 of a hydraulic excavator 1 working in fields is measured. Measured data is stored in a memory of a controller 2 and then transferred to a base station computer 3 via satellite communication, an FD, etc. to be stored in a database 100. At each repair/replacement of a part in each hydraulic excavator, the base station computer 3 calculates, based on the operation data, a replacement time interval of the part on the basis of the working time per section to which the part belongs, and then stores and accumulates it. The base station computer also reads the stored data for each hydraulic excavator, determines, for each part, a replacement rate of the part having the substantially equal replacement time interval, and calculates a target replacement time interval of the part in accordance with the replacement time interval corresponding to a maximum replacement rate.

Abstract: In a working apparatus, a recessed portion is formed at an end surface of a pin provided at a boom to house a case of an angle sensor in the recessed portion. A flange is projected from the case along the direction of the axis of an input shaft so as to enclose the input shaft outside the movement range of a lever. By projecting the flange further out than the distance over which the input axis projects out, the protection provided by the flange for the input shaft is enhanced.

Abstract: A hydraulic excavator 1 working in fields includes a controller 2 for measuring a working time for each of an engine 32, a front 15, a swing body 13, and a travel body 12, storing measured data in a memory of the controller 2, and then transferring it to a base station computer 3 via satellite communication, an FD, etc. The transferred data is stored as a database 100 in the base station computer 3. The base station computer 3 reads the data stored in the database 100 for each hydraulic excavator, calculates a working time of a part belonging to each section on the basis of the working time of that section, and compares the calculated working time with a preset target replacement time interval of the relevant part, thereby calculating a remaining time up to next replacement of the relevant part and managing the scheduled replacement timing thereof.

Abstract: A construction machine comprises a location detector for detecting location information for the construction machine, a determination device for determining whether or not location information is to be transmitted and outputting a transmission signal if it is determined that information is to be transmitted, and a transmitter for transmitting the detected location information to a base station in response to the transmission signal.

Abstract: The present invention is applied to a system comprised of large number of hydraulic excavators 1 deployed at construction sites and a base station 16. Each hydraulic excavator 1 is provided with a storage unit (memory 402), a control unit (CPU 401) for executing the work operation and receiving as input a quantitative machine status relating to the work operation, and a communications device 42. The base station 16 is provided with a communications device 16a, a management server 17 for identifying the serial number of the hydraulic excavator 1 and transferring information, and a database 18 for storing various information. The control unit of the hydraulic excavator 1 and the management server 17 of the base station 16 transfer information.

Abstract: A method for outputting failure handling method includes: detecting conditions of each part of a working machine; transmitting condition signals representing the detected conditions; receiving the condition signals; calculating a handling method for a failure showed by the received condition signals; and transmitting a handling signal representing the calculated handling method.

Abstract: Hardened surface layers (12) and (14) of a nitride or other compound, which is higher in hardness than dirt or soil, are formed on the inner peripheral surface (11B) of each metal bush (11) and on the outer peripheral surface (13A) of each connecting pin (13) which constitute a crawler belt (7), respectively. In addition, resinous sliding bearings (15) which are each formed of an ultra-high molecular weight polyethylene-base resin are fitted in transversely spaced positions on the inner periphery of each metal bush (11) of the crawler belt. The resinous sliding bearing (15) is provided with a plural number of recessed grooves (16) on and around its inner periphery as axially extended grooves.

Abstract: The position of a working machine is detected, a position signal representing the detected position is transmitted, the position signal is received, management information relating to the working machine is calculated based on the received position signal, and the calculated management information is transmitted to the working machine. Example of management information is type of attachment depending on soil quality, and weather forecasts.

Abstract: In a hose rupture control valve unit comprising a main valve constituted by a poppet valve member and a pilot valve constituted by a spool valve member, a hydraulic fluid can be supplied from a hose connection chamber to a cylinder connection chamber even in the condition of a pilot pressure acting upon the spool valve member, so that the smooth operation can be obtained without a delay in opening of the poppet valve member upon an abrupt reversed lever operation.

Abstract: A controller 2 is mounted on a hydraulic excavator 1 working in fields. An operating time for each of an engine 32, a front 15, a swing body 13 and a travel body 12 is measured and stored in a memory of the controller 2. The measured data is transferred to a base station computer 3 through satellite communication, a FD, etc. and stored in a database 100 inside the base station computer 3. The base station computer 3 reads, per hydraulic excavator, the data stored in the database 100 and then prepares and outputs a distribution graph of the number of operated machines with respect to the working time (engine running time) of the hydraulic excavator. While looking at the distribution graph, a machine maker estimates the number of hydraulic excavators to be renewed and estimates the sales quantity of hydraulic excavators, thereby setting up a production plan of hydraulic excavators.

Abstract: Hydraulic excavators 1 working in fields each include a controller 2, and an operating time is measured for each of an engine 32, a front 15, a swing body 13 and a track body 12. The measured data is stored in a memory of the controller 2, transferred to a base station computer 3 through satellite communication, an FD, etc., and stored in a database 100 of the base station computer 3. In the base station computer 3, the data stored in the database 100 is read out for each of the hydraulic excavators to obtain a value of an index (e.g., a travel ratio) regarding the state of use of a particular one of the hydraulic excavators and a distribution of the number of operated hydraulic excavators of the same model as the particular hydraulic excavator with respect to the index. The index value and that distribution are compared with each other to determine whether the particular hydraulic excavator is an optimum model.

Abstract: An input/output port 1 of a hose rupture control valve unit 100 is attached to a bottom port of a hydraulic cylinder 102, and an input/output port 2 is connected to one of actuator ports of a control valve 103 via an actuator line 105. The valve unit comprises a poppet valve body 5 serving as a main valve, a first spool valve body 6 serving as a pilot valve operated with a pilot pressure supplied as an external signal and having a pilot variable throttle portion 6a to operate the poppet valve body 5, a second spool valve body 50 operated with a pilot pressure and having a sub-variable throttle portion 50a to control a sub-flow rate, and a small relief valve 7 having the function of an overload relief valve.

Abstract: The present invention concerns a crawler belt (7) incorporating a sealing devices (21), which are each constituted by a coned disc spring (23) and a seal ring (22), to seal up gap spaces between track links (8) and bushes (13). A seal anchor hole (12) is provided in each one of outer link portions (9) of track links (8) of the crawler belt (7), and the sealing device (21) is fitted in the seal anchor hole (12) between an outer link portion (9) and an opposing end face (13A) of a bush (13). The sealing device (21) includes the seal ring (22) in the shape of an O-ring, and the coned disc spring (23) which is arranged to press the seal ring (22) resiliently against peripheral wall surface (12B) of the seal anchor hole (12) and the end face (13A) of the bush (13).