Abstract: A relay (25) connects and disconnects an electrical circuit to which an inverter (16) and an electricity storage device (19) are connected. A BCU (22) controls the electricity storage device (19). An HC (27) controls an electric motor (15), the inverter (16) and the BCU (22). The HC (27) and the BCU (22) respectively have FET switches (30, 31) for controlling supply and stop of the excitation current in the relay (25). When the electricity storage device (19) is determined to be in an abnormal state, the BCU (22) transmits an abnormal signal to the HC (27), and when a predetermined time has elapsed, turns off (opens) the first FET switch (30) of the BCU (22). The HC (27) executes stop processing based upon the abnormal signal received from the BCU (22) and then turns off (opens) the second FET switch (31) of the HC (27).

Abstract: To provide a construction machine that can highly precisely control branch flows from a hydraulic pump to a plurality of hydraulic actuators without being affected by load conditions. A controller (100) has a meter-out valve control section (140) configured to calculate a target opening area of a second meter-out valve (65a) (65b) according to a pressure difference between a supply pressure and a second meter-in pressure, or calculate a target opening area of a first meter-out valve (55a) (55b) according to a pressure difference between the supply pressure and the first meter-in pressure.

Abstract: A pedal operation switching mechanism can switch a foot pedal to any movement pattern of three movement patterns of a front/rear step pattern of being capable of the operation of depressing a front side of the foot pedal from a neutral position of a rotational part of a pilot valve and of being capable of the operation of depressing a rear side of the foot pedal from the neutral position of the rotational part, a front step limit pattern of being capable of the operation of depressing only the front side of the foot pedal from the neutral position of the rotational part, and a fixing pattern of fixing the movement of the foot pedal in the neutral position of the rotational part.

Abstract: A work vehicle is provided. The work vehicle is capable of notifying an operator of a state close to overheating of a temperature of a cooling oil that cools a brake device before the temperature overheats. A controller (10) in a work vehicle (100) compares each detection value detected from a brake pressure sensor (26) and a vehicle speed sensor (15) to each threshold (V1, P1, R1) predetermined corresponding to each sensor. The controller (10) outputs a warning command that a temperature of a cooling oil is likely to overheat to a notification device (28) when a state that at least one detection value is equal to or more than the threshold and when a state that at least one detection value is equal to or more than the threshold continues for a first duration (t1) or more.

Abstract: To provide a power regeneration system for a working vehicle that can effectively use a regenerative electric energy. A first electric circuit for supplying an electric power generated by the first generator to a traveling motor, a voltage detector for detecting an actual voltage of the first electric circuit, a second electric circuit for supplying an electric power generated by a second generator to an auxiliary device, a step-down device connected to the first electric circuit and the second electric circuit, and a controller are provided. The controller estimates the voltage of the first electric circuit after a predetermined time has elapsed from the present time, based on information on a traveling state of a work vehicle and the actual voltage detected by the voltage detector, and outputs a drive command to the step-down device when the estimated voltage is equal to or more than a threshold.

Abstract: A controller (18) calculates, based on a target loading weight (P) that is a target value of a total weight of working objects to be loaded into a hauling vehicle, a set loading time number indicative of a loading time number required for the construction machine before the target loading weight (P) is reached and bucket shape information indicative of a shape of a bucket (7), an appropriate loading weight (Wa) that is an appropriate value of the weight of the working objects to be loaded into the hauling vehicle by a single time loading work by the construction machine, creates an appropriate amount illustration (30) that is an illustration of a state at which the working objects of the appropriate loading weight (Wa) are loaded into the bucket and that illustrates the state of the working objects, based on the appropriate loading weight (Wa) and the bucket shape information, and controls a display device (19) to display an illustration (29) of the bucket (7) and the appropriate amount illustration (30) in a

Abstract: Provided is a hydraulic excavator (1) that performs work by operating an arm (9) after moving a bucket (10) to a work start position. An operation determination section (81c) determines, based on an operation performed on an operation device, whether a front work device (1A) is engaged in a work preparation operation for moving the bucket to the work start position. When the operation determination section determines that the front work device is engaged in the work preparation operation at the time of operation of the operation device, an actuator control section (81) controls a bucket cylinder (7) such that the angle of a work tool with respect to a target surface coincides with a preset target angle (?TGT).

Abstract: Provided is a wheel loader in which the speed position of the transmission can be easily changed with a small number of switches. The wheel loader 1 includes a tilting angle sensor 9 for detecting the tilting angle of the vehicle body. In case that the vehicle body is traveling on an uphill or a downhill with a transmission 33 in a higher speed position than the lowest speed position, and the tilting angle detected by the tilting angle sensor 9 is not smaller than a prescribed threshold value, a transmission control device 45 sends the transmission 33 a command to downshift the transmission 33 one speed position by each operation of a shiftdown switch 62.

Abstract: It is determined whether a velocity estimation model is established from an actual operating velocity Vr and a target operating velocity Vt of each of actuators 20A, 21A, and 22A; in a case in which the velocity estimation model is established, a dynamic center-of-gravity position of a hydraulic excavator 1 in a case in which each of the actuators 20A, 21A, and 22A is suddenly stopped from a driven state is predicted from an estimated operating velocity Ve; in a case in which the velocity estimation model is not established, the dynamic center-of-gravity position is predicted from the actual operating velocity Vr and it is determined whether to execute control intervention using the predicted dynamic center-of-gravity position; and in a case in which it is determined to execute the control intervention, the target operating velocity Vt is corrected in such a manner that each of the actuators 20A, 21A, and 22A slowly decelerate.

Abstract: A main controller and a hybrid controller control an engine, an assist generator motor, a hydraulic pump and an electricity storage device. In this case, the hybrid controller is provided with a performance state recovery part that performs performance state recovery of the electricity storage device. In a case where a performance state amount varying with repetition of a discharge and a charge of the electricity storage device, specifically, a current integrated value ratio of the electricity storage device goes beyond a predetermined threshold value (L1%), the performance state recovery part limits power of the hydraulic pump. Thereby, the performance state recovery part performs the performance state recovery of the electricity storage device.

Abstract: A work machine capable of driving each actuator more speedily and more accurately by ensuring high operability in a case of operator's manual operation, while accurately supplying a hydraulic fluid at a target flow rate to the actuator without depending on a load fluctuation in a case of automatic control over a machine body in response to a command input from a controller is provided. The controller controls a plurality of auxiliary flow controllers in such a manner that supply flow rates to a plurality of directional control valves from hydraulic pumps either fluctuate in response to load fluctuations of a plurality of hydraulic actuators when an area limiting control function invalidation instruction is issued, or do not fluctuate in response to the load fluctuations of the plurality of hydraulic actuators when an area limiting control function validation instruction is issued.

Abstract: A controller (40) of a hydraulic excavator (1) includes: a first distance calculation section (43f) calculating a first distance D1 that is a distance between a bucket toe and a target surface on a virtual straight line Lv extended vertically from the bucket toe, based on position information on the bucket toe and position information on the target surface (700); and a second distance calculation section (43g) calculating a second distance D2 that is a distance between the target surface and a current landform on the virtual straight line Lv, based on the position information on the bucket toe and the position information on the target surface and position information on the current landform 800. A display device (53a) displays the first distance D1 and the second distance D2.

Abstract: A hydraulic excavator includes: a multijoint type front implement that is configured by coupling a plurality of driven members including a bucket; inertial measurement units that detect posture information about the plurality of driven members; and a calibration value computing section that computes calibration parameters used in calibration of detection results of the inertial measurement units; and a work position computing section that computes a relative position of the bucket to the machine body on the basis of the detection results of the inertial measurement units and the computation result of the calibration value computing section, and the calibration value computing section computes the calibration parameters on the basis of the detection results of the inertial measurement units in a plurality of postures of the front implement in which a reference point set on any of the plurality of driven members in advance matches a reference position.

Abstract: A controller (45) is provided with an elapse time measuring section (47A) that measures an elapse time (tx) elapsed since an initial use of an accumulator (29) based upon a reset signal from a reset switch (44), a number-of-operations measuring section (47B) that measures a number of operations of the accumulator (29), that is, a number (N) of boom lowering operations after a reset, based upon a detection signal from an accumulator side pressure sensor (39), a gas permeation amount estimating section (47C) that estimates an estimation gas permeation amount (Qloss) of the accumulator (29), a sealed gas pressure estimating section (47D) that finds an estimation sealed gas pressure (Pgs) of a gas chamber (29B) of the accumulator (29), and an accumulator degradation determining section (47E) that determines a degradation condition of the accumulator (29) and outputs the determination result.

Abstract: A differential case (23) is therein provided with a plurality of rotating discs (38) that are spline-coupled to an outer peripheral side of aright side gear (35), and a plurality of non-rotating discs (39) that are respectively arranged between the respective rotating discs (38) and are non-rotatable relative to the differential case (23) and are movable in a left-right direction. A pressure ring (43) that presses the non-rotating discs (39) toward the rotating discs (38) is disposed between a right retainer (41) positioned in the right side gear (35)-side and the non-rotating disc (39). The right retainer (41) is therein provided with a piston accommodating part (41D) in a position facing the pressure ring (43) in the left-right direction. The piston accommodating part (41D) is therein provided with a piston (46) that is displaced by hydraulic pressure to press the non-rotating discs (39) against the rotating discs (38) through the pressure ring (43).

Abstract: Work efficiency is improved while necessary and sufficient monitoring on the surroundings of a working machine is performed. A working machine includes an undercarriage 132 on which an upperstructure 131 including a front working device is mounted in a swingable manner, and includes a surrounding monitoring device 200 that monitors surroundings. The surrounding monitoring device 200 has an information controller 161 that: sets a working region by use of terrain data and work states received from sensors detecting work states of the front working device of the working machine; calculates proximity for each of the obstacles around the working machine by use of the working regions and relative positions of each of obstacles and the working machine, the obstacles being detected by an obstacle sensor that detects obstacles around the working machine; and outputs a control instruction in accordance with the proximity.

Abstract: An engine cooling system (22) includes an engine (11), an engine cooling pipe line (23), an engine water pump (24) and an engine radiator (25). An electricity storage device cooling system (27) includes an electricity storage device (19), an electricity storage device cooling pipe line (28), an electricity storage device water pump (29) and an electricity storage device radiator (31). Different heat-transfer media (engine cooling water and electricity storage device cooling water) flow respectively in the engine cooling system (22) and the electricity storage device cooling system (27). Further, a heating heat exchanger (32) is provided in the halfway of the engine cooling pipe line (23) and in the halfway of the electricity storage device cooling pipe line (28) for performing heat exchange between the engine cooling water and the electricity storage device cooling water.

Abstract: A hydraulic oil resupply device (40) is provided between first accumulators (15F, 15R) in a manual braking operation circuit (11) and a second accumulator (25) in an automatic brake circuit (24). The hydraulic oil resupply device (40) resupplies hydraulic oil accumulated in the second accumulator (25) to the first accumulators (15F, 15R) at the operating of a manual braking operation by an operator. This configuration can suppress a rising speed of a brake pressure at the manual operation braking from being slow. Accordingly, in a vehicular brake system, it is possible to enhance a braking capability by the manual braking operation and improve the reliability.

Abstract: A dump truck 100 including: an engine 1; a generator 10 driven by the engine 1; and a pair of driving wheels 3L and 3R arranged to the left and right of a vehicle body frame 7 includes: a traveling electric motor 12L including a plurality of electric motors 12La, 12Lb, and 12Lc that are coupled to the driving wheel 3L and simultaneously drive the driving wheel 3L; and a traveling electric motor 12R including a plurality of electric motors 12Ra, 12Rb, and 12Rc that are coupled to the driving wheel 3R and simultaneously drive the driving wheel 3R. Thereby, drive systems corresponding to loads of dump trucks or the like can be configured using identical components.

Abstract: An object of the present invention is to provide a construction machine capable of suppressing lugging down of an engine irrespective of contents of operation of an operator and the load state of a hydraulic actuator.