Abstract: A hydraulic excavator includes a computer-aided construction controller for performing machine control to operate a front work implement based on detected results from posture sensors and predetermined conditions. The computer-aided construction controller has a calibration posture storing section that stores at least one predetermined calibration posture of the front work implement for calibrating the posture sensors, and a calibration posture controlling section that carries out the machine control to inactivate the hydraulic actuators if detection target values of the posture sensors in the calibration posture and the detected results from the posture sensors are equal to each other. The time required for calibration can thus be shortened by increasing the operability for adjusting a calibration posture.

Abstract: In a work machine including a solenoid valve that generates a pilot pressure to drive a directional control valve with use of the delivery pressure of a pilot pump as a source pressure, a shut-off valve that shuts off a hydraulic operating fluid from the pilot pump to the solenoid valve, a first sensor that senses the amount of operation of an operation lever, and a second sensor that senses a state amount relating to operation of the solenoid valve, whether or not an abnormality of the second sensor exists is determined on the basis of a sensing signal of the second sensor. When it is determined that the second sensor is abnormal, on the basis of a sensing signal of the first sensor, an opening command is made to the shut-off valve if operation of the operation lever is sensed, and a closing command is made to the shut-off valve if the neutral state of the operation lever is sensed.

Abstract: In a work machine including a solenoid valve that generates a pilot pressure to drive a directional control valve with use of the delivery pressure of a pilot pump as a source pressure, a shut-off valve that shuts off a hydraulic operating fluid from the pilot pump to the solenoid valve, a first sensor that senses the amount of operation of an operation lever, and a second sensor that senses a state amount relating to operation of the solenoid valve, whether or not an abnormality of the second sensor exists is determined on the basis of a sensing signal of the second sensor. When it is determined that the second sensor is abnormal, on the basis of a sensing signal of the first sensor, an opening command is made to the shut-off valve if operation of the operation lever is sensed, and a closing command is made to the shut-off valve if the neutral state of the operation lever is sensed.

Abstract: There is provided an information controller (60) that calculates a work amount based on the positions of a construction target surface and a current surface in a set coordinate system set in the operational plane of a multi-joint type front work device (30), and a construction distance (L) by which a construction target surface and a current surface of configurations equivalent to those of the construction target surface and the current surface continue on a construction object, and that calculates a predicted requisite time of the work amount of a work based on the work amount and processing speed. A construction completion prediction time calculated by the information controller (60) or a prediction time calculated from the construction completion prediction time is displayed by a display device (67).

Abstract: To provide an identification system for a work machine which is capable of preventing a setting error, the identification system for a work machine includes: a main control unit to control the entirety of a work machine; and a plurality of power control units to control components of the work machine. The main control unit acquires information about the entire vehicle body of the work machine. Each of the power control units acquires different information about a state of one of the components from that acquired by the other power control units, on the basis of a installation site of the power control unit installed on the work machine. In addition, the power control unit sets a function of the power control unit on the basis of the information about the state and the information about the entire vehicle body.

Abstract: A hydraulic excavator (1) includes a hydraulic pump (22) driven by an engine (20), an electromagnetic proportional valve (24) for hydraulic pump that adjusts pump torque of the hydraulic pump (22) in response to a pump torque target value (Tp), a hydraulic actuator operated by a delivery pressure of the hydraulic pump (22), a motor generator (30) connected to the engine (20), and a controller (26) configured to calculate the pump torque target value (Tp). The controller (26) acquires a pump torque adjustment amount (Qadj) based on a deviation (?AH) between a current integrating value (AH1) acquired by integrating a value of a current flowing into the motor generator (30) when the hydraulic actuator is driven and a current integrating reference value (AH0).

Abstract: To provide an identification system for a work machine which is capable of preventing a setting error, the identification system for a work machine includes: a first control device to control the entirety of a work machine; and a plurality of second control devices to control components of the work machine. The first control device acquires information about the entire vehicle body of the work machine. Each of the second control devices acquires different information about a state of one of the components from that acquired by the other second control devices, on the basis of a installation site of the second control device installed on the work machine. In addition, the second control device sets a function of the second control device on the basis of the information about the state and the information about the entire vehicle body.

Abstract: The invention provides a work machine that achieves high accuracy of forming a target construction surface and reduced fuel consumption. A trajectory corrective Pi pressure calculation section calculates a trajectory corrective pressure, which is a control signal for a boom cylinder, based on the distance from a front work device to a target construction surface such that the motion trajectory of the work device is maintained above the target construction surface. A power corrective Pi pressure calculation section calculates a power corrective pressure, which is a control signal for the boom cylinder, based on the bottom pressure of an arm cylinder when the difference between the target power and actual power of the arm cylinder is larger than a predetermined output power value. The boom cylinder is controlled based on the larger of the power corrective pressure and the trajectory corrective pressure while the arm cylinder is being operated.

Abstract: A main controller 28 performs automatic stop control to stop an engine in a case where a preset automatic stop condition is satisfied, and includes a power source control processing section 283 controlling power supplied from a capacitor to an electric or electronic facility 70. The power source control processing section 283 estimates a charge amount by which the capacitor 40 is charged by the alternator 41 while an engine 9 is in operation, estimates an electric discharge amount corresponding to power supplied from the capacitor 40 to the electric or electronic facility 70 while the engine 9 is stopped under the automatic stop control, and stops supply of power from the capacitor 40 to the electric or electronic facility 70 when the electric discharge amount is determined to be larger than the charge amount while the engine 9 is stopped under the automatic stop control. This allows reliable suppression of degradation of the capacitor while the engine is under the automatic stop control.

Abstract: A hydraulic excavator 1 includes a computer-aided construction controller 60 for performing machine control to operate a front work implement based on detected results from posture sensors 63, 65 and 67 and predetermined conditions. The computer-aided construction controller 60 has a calibration posture storing section 60a that stores at least one predetermined calibration posture of the front work implement for calibrating the posture sensors, and a calibration posture controlling section 60b that carries out the machine control to inactivate the hydraulic actuators if detection target values of the posture sensors in the calibration posture and the detected results from the posture sensors are equal to each other. The time required for calibration can thus be shortened by increasing the operability for adjusting a calibration posture.

Abstract: A program rewriting device for a construction machine rewrites a program of an on-board controller is provided with a mode determination section that determines whether the operation mode of the construction machine is a maintenance mode in which the program can be rewritten and the operation of an actuator is prevented, a preparation mode in which the rewriting of the program and the operation of the actuator are prevented, or a work mode in which the rewriting of the program is prevented and the operation of the actuator is permitted, an urgency degree determination section determines the degree of urgency for rewriting of an update program, a rewriting execution section that, at the time of rewriting the program, when it has been determined that the operation mode is the preparation mode and the degree of urgency is high, rewrites the program by switching the operation mode to the maintenance mode.

Abstract: A hydraulic excavator (1) includes a hydraulic pump (22) driven by an engine (20), an electromagnetic proportional valve (24) for hydraulic pump that adjusts pump torque of the hydraulic pump (22) in response to a pump torque target value (Tp), a hydraulic actuator operated by a delivery pressure of the hydraulic pump (22), a motor generator (30) connected to the engine (20), and a controller (26) configured to calculate the pump torque target value (Tp). The controller (26) acquires a pump torque adjustment amount (Qadj) based on a deviation (?AH) between a current integrating value (AH1) acquired by integrating a value of a current flowing into the motor generator (30) when the hydraulic actuator is driven and a current integrating reference value (AH0).

Abstract: A work machine that can prevent restarting of an engine against a will of an operator from an idle stop state is provided. A hydraulic excavator includes a display device that displays a confirmation screen image for allowing an operator to confirm whether or not an engine is to be restarted from an idle stop state, and an inputting device that allows the operator to input a restart instruction for the engine in an interlocked relationship with the display of the confirmation screen image. A machine controller includes a restart controlling section that restarts the engine based on the restart instruction for the engine inputted by the inputting device.

Abstract: At the time of starting up an engine (9) using an assist motor generator (10), a main controller (28) lowers a lower limit value in a charge/discharge range of an electricity storage device (19) from a first lower limit value (min1) to a second lower limit value (min2) through an energy management control part (28B). The main controller (28) heightens the lower limit value in the charge/discharge range of an electricity storage device (19) from the second lower limit value (min2) to the first lower limit value (min1) when the start of the engine (9) is completed. Further, the main controller (28) displays engine stop prohibition information on a display device (30) when the start of the engine (9) is completed and when an SOC of the electricity storage device (19) falls below the first lower limit value (min1).

Abstract: There is provided an information controller (60) that calculates a work amount based on the positions of a construction target surface and a current surface in a set coordinate system set in the operational plane of a multi-joint type front work device (30), and a construction distance (L) by which a construction target surface and a current surface of configurations equivalent to those of the construction target surface and the current surface continue on a construction object, and that calculates a predicted requisite time of the work amount of a work based on the work amount and processing speed. A construction completion prediction time calculated by the information controller (60) or a prediction time calculated from the construction completion prediction time is displayed by a display device (67).

Abstract: The invention provides a work machine that achieves high accuracy of forming a target construction surface and reduced fuel consumption. A trajectory corrective Pi pressure calculation section calculates a trajectory corrective pressure, which is a control signal for a boom cylinder, based on the distance from a front work device to a target construction surface such that the motion trajectory of the work device is maintained above the target construction surface. A power corrective Pi pressure calculation section calculates a power corrective pressure, which is a control signal for the boom cylinder, based on the bottom pressure of an arm cylinder when the difference between the target power and actual power of the arm cylinder is larger than a predetermined output power value. The boom cylinder is controlled based on the larger of the power corrective pressure and the trajectory corrective pressure while the arm cylinder is being operated.

Abstract: A program rewriting device for a construction machine rewrites a program of an on-board controller is provided with a mode determination section that determines whether the operation mode of the construction machine is a maintenance mode in which the program can be rewritten and the operation of an actuator is prevented, a preparation mode in which the rewriting of the program and the operation of the actuator are prevented, or a work mode in which the rewriting of the program is prevented and the operation of the actuator is permitted, an urgency degree determination section determines the degree of urgency for rewriting of an update program, a rewriting execution section that, at the time of rewriting the program, when it has been determined that the operation mode is the preparation mode and the degree of urgency is high, rewrites the program by switching the operation mode to the maintenance mode.

Abstract: A work machine that can prevent restarting of an engine against a will of an operator from an idle stop state is provided. A hydraulic excavator includes a display device 52 that displays a confirmation screen image 58 for allowing an operator to confirm whether or not an engine 32 is to be restarted from an idle stop state, and an inputting device 54 that allows the operator to input a restart instruction for the engine in an interlocked relationship with the display of the confirmation screen image 58. A machine controller 100 includes a restart controlling section 118 that restarts the engine 32 based on the restart instruction for the engine inputted by the inputting device 54.

Abstract: A management server (32) is provided in a position away from a hydraulic excavator (1). An operator ID and a vehicle body ID and output characteristic information are stored in a memory device (32A) in the management server (32) in such a manner as to be associated with operability desired by each of operators. The management server (32) extracts the output characteristic information in conformity with the operability desired by an operator from the operator ID and the vehicle body ID, and outputs the extracted output characteristic information to the hydraulic excavator (1). A control device (17) in the hydraulic excavator (1) changes the output characteristics of hydraulic actuators (4D), (4E), (4F), (2B), (3B) based upon the output characteristic information stored in a memory (19).

Abstract: A management server (32) is provided in a position away from a hydraulic excavator (1). An operator ID and a vehicle body ID and output characteristic information are stored in a memory device (32A) in the management server (32) in such a manner as to be associated with operability desired by each of operators. The management server (32) extracts the output characteristic information in conformity with the operability desired by an operator from the operator ID and the vehicle body ID, and outputs the extracted output characteristic information to the hydraulic excavator (1). A control device (17) in the hydraulic excavator (1) changes the output characteristics of hydraulic actuators (4D), (4E), (4F), (2B), (3B) based upon the output characteristic information stored in a memory (19).