Abstract: In a rental estimation method according to the present invention, rental information with regard to rental devices is provided to a customer through a data exchange between a terminal (9) of the customer and a management server (5) of a rental company. The rental estimation method includes a data input step for entering work content data indicating a work content through the customer terminal (9), and a necessary device reporting step for reading out a list of a plurality of necessary devices matching the work content and rental information corresponding to the necessary devices from a predefined database (2 to 4) and for providing them to the customer.

Abstract: A joining directional control valve 13 is disposed to supply, to an arm cylinder 4, not only a hydraulic fluid delivered from a first hydraulic pump 1, but also a hydraulic fluid delivered from a second hydraulic pump 2 when an arm directional control valve 14 is driven. Respective delivery pressures of the hydraulic pumps 1, 2 are detected by pressure sensors 101, 102, and the opening area of a recovery control valve 6 is controlled depending on a lower one of the detected pressures from the pressure sensors 101, 102 such that, even in the combined operation of the arm cylinder 4 and another actuator 3, 4, the hydraulic fluid can be recovered for return to the arm cylinder 4 when the load pressure of the arm cylinder 4 is low. Thus, by supplying the hydraulic fluids from the two hydraulic pumps to the particular actuator for which the hydraulic fluid is to be recovered, a recovery flow rate is ensured when the load of the particular actuator is low in the combined operation.

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: A security system of a construction machine of the present invention has a construction machine, a base station and a communication device. The construction machine comprises a data sending and receiving portion for sending first information, a storage portion for storing received information, and a control portion for controlling an operation of the construction machine. The base station receives the first information from the data sending and receiving portion of the construction machine and sends second information to the construction machine and manages the construction machine. It is configured so that the communication device is connected to the base station through a communication network and can send third information to the construction machine through the base station.

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 working machine failure diagnosis method for performing a failure diagnosis by transmitting and receiving signals through communication devices provided at a working machine and at an information management center, according to the present invention, includes: a first step in which a first signal related to a failure of the working machine is generated at the working machine and the first signal is transmitted to the information management center from the working machine via the communication devices; a second step in which, after the first signal is transmitted, the information management center generates a second signal for identifying a location of the failure based upon the first signal and the second signal is then transmitted from the information management center to the working machine via the communication devices; and a third step in which failure information corresponding to the first signal and the second signal is provided to an operator.

Abstract: A method and system for managing a construction machine whereby working time for each of different parts of a hydraulic excavator is measured. Measured data is stored in a memory of a controller and then transferred to a base station computer via satellite communication to be stored in a database. At each repair/replacement of a part in each hydraulic excavator, the base station computer 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 a 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: A function changing system of construction machinery includes a hydraulic excavator and a base station. The hydraulic excavator is deployed at a construction site and is provided with a rewritable memory storing control programs and/or data required for control of the machinery, a CPU for reading out the control programs from the memory and executing them, and a communications device The base station is provided with a communications device, a center server for identifying the serial number of the hydraulic excavator and transferring information with the control unit, and a database managed by the center server and storing control programs corresponding to the hydraulic excavator. When changing or switching an attachment of the hydraulic excavator, information is transferred with the center server of the base station and the control programs or data stored in the storage unit are rewritten to enable work suited to the changed part.

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: Construction machine management, permitting operation of a construction machine only under specified conditions and inhibiting its operation in case it is in a state incongruent with preset working conditions. Working conditions for each construction machine are set up by a working conditions setup means, including a geographically divided working area and a working time zone in which a construction machine is allowed to operate in a specified working area. Setup working conditions are stored in a memory means. At the time of starting a construction machine, the status of the construction machine is checked for by a status checkup means which is adapted to check for current position of the construction machine and current time against the working area and working time zone of the setup working conditions.

Abstract: A method and system for managing a construction machine and processing apparatus therefor includes a controller 2 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 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: A hydraulic excavator periodically measures its current location at predetermined time intervals by the GPS device in an inoperative state where its engine key is in the off position and sends the current location data and time data to a management server by a main controller and communicator. The management server receives the periodically sent location data at its communicator and successively stores it in its memory. The current location data and the measurement time data to provide a location confirmation service by a location information provider. Changes in location can be confirmed on a map, the movement of the hydraulic excavator can be tracked, and assistance can be given for confirmation of location and prevention of theft.

Abstract: A maintenance system of a hydraulic excavator (11) is provided with a maintenance monitoring device (21), a maintenance management server (12) for managing trouble information and operating information for each working machine, a model information server (13), and a service personnel mobile terminal (14) connected to one another through the Internet (15). When trouble occurs in the hydraulic excavator, the maintenance system (21) transmits trouble information to the maintenance management server (12), and the maintenance management server (12) transmits information on occurrence of trouble to the mobile terminal (14) and displays it on a display unit. This system manages the maintenance manuals and other data for each model in a model information database separate from the maintenance database and correlates the two databases based on the model data.

Abstract: A working machine failure diagnosis method for performing a failure diagnosis by transmitting and receiving signals through communication devices provided at a working machine and at an information management center, according to the present invention, includes: a first step in which a first signal related to a failure of the working machine is generated at the working machine and the first signal is transmitted to the information management center from the working machine via the communication devices; a second step in which, after the first signal is transmitted, the information management center generates a second signal for identifying a location of the failure based upon the first signal and the second signal is then transmitted from the information management center to the working machine via the communication devices; and a third step in which failure information corresponding to the first signal and the second signal is provided to an operator.

Abstract: Assessment information needed to calculate a used vehicle assessment value of a hydraulic excavator 10 is input to a portable telephone 20 and is then transmitted from the portable telephone 20. The transmitted assessment information is received at a manufacturer's base station 40 at a remote location. The used vehicle assessment value of the hydraulic excavator 10 is calculated based upon the received assessment information, and history information and operation information on the hydraulic excavator 10 read out from an operation information database 43 and a history database 42 in correspondence to an ID number assigned to the hydraulic excavator which is included in the assessment 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: A hydraulic drive system includes a hose rupture control valve unit 200 having a poppet valve member 5 serving as a main valve for opening and closing communication between a cylinder connection chamber 8 and a hose connection chamber 9, a spool valve member 6 disposed in pilot passages 15a, 15b connecting a back pressure chamber 10 and the hose connection chamber 9 of the poppet valve member 5. The spool valve member is operated by a pilot pressure supplied as an external signal and operates the poppet valve member 5, and a small relief valve 7 having the function of an overload relief valve. A check valve 39 is disposed in the pilot passage 15b for cutting off a flow of the hydraulic fluid from the hose connection chamber 9 to the back pressure chamber 10.

Abstract: To keep one of three hydraulic pumps unaffected by variations in torque of the remaining hydraulic pumps when the three hydraulic pumps are used, displacements of the first and second hydraulic pumps are controlled based on their own delivery pressures P1, P2 and a pressure P3′ obtained by reducing through a reducing valve 14 a delivery pressure P3 from the third hydraulic pump, while a displacement of the third hydraulic pump 3 is controlled only by its own delivery pressure P3. The pressure oil delivered from the third hydraulic pump 3, therefore, remains unaffected by variations in delivery flow rates from the first and second hydraulic pumps 1,2, in other words, by variations in their torque consumptions, so that the third hydraulic pump is assured to provide a stable flow rate.

Abstract: A security system of a construction machine of the present invention has a construction machine, a base station and a communication device. The construction machine comprises a data sending and receiving portion for sending first information, a storage portion for storing received information, and a control portion for controlling an operation of the construction machine. The base station receives the first information from the data sending and receiving portion of the construction machine and sends second information to the construction machine and manages the construction machine. It is configured so that the communication device is connected to the base station through a communication network and can send third information to the construction machine through the base station.

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.