Abstract: A construction machine includes a posture sensor provided on a front member of a front work implement. An external environment recognition device detects an object around a main body, and a controller calculates a dead angle range from a recognition range of the external environment recognition device. An assumed movement range in which a moving body is assumed to exist in the dead angle range in a period of time determined in advance is calculated; and a movable range within which the front work implement is movable in a period of time determined in advance is calculated on the basis of the posture information detected by the posture sensor. Preventative control is then performed for preventing contact between the moving body and the front work implement on the basis of the assumed movement range of the moving body and the movable range of the front work implement.

Abstract: An object of the present invention is to provide a construction machine that allows easy and accurate calibration of a pressure sensor and enables accurate control of hydraulic actuators.

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: 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: A construction machine is provided that can cause each hydraulic actuator to accurately operate according to operation by an operator in combined operation in which a hydraulic fluid of a hydraulic pump is subjected to flow dividing and is supplied to plural hydraulic actuators. A controller 10, in a case of determining that combined operation is being carried out, controls a regulator 7a in such a manner that the delivery flow rate of a hydraulic pump 7 becomes larger than the total target flow rate of plural hydraulic actuators 4a, 5a, and 6a, and controls the respective opening amounts of plural directional control valves 8a1, 8a3, and 8a5 in such a manner that the difference between the respective target flow rates of the plural hydraulic actuators and the respective inflow flow rates of the plural hydraulic actuators sensed by velocity sensors 12 to 14 becomes small.

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 construction machine that precisely enables derivation of the operation characteristics of hydraulic actuators in a high-velocity area with less calibration operation is provided. A controller (10) has a calibration mode in which the controller (10) derives operation characteristics (?(xs)) representing a relation among a spool position (xs) of a meter-in valve (8a1), an operation velocity (Va) of a hydraulic actuator (4a), and a differential pressure (?P) across the meter-in valve (8a1), and is configured to, in a case where the spool position (xs) of the meter-in valve (8a1) has changed in a direction to increase the opening area of the meter-in valve (8a1) in the calibration mode, output a command signal to increase the opening area of a bleed-off valve (8b1) to a bleed-off solenoid proportional pressure-reducing valve (8b2) as a command signal to reduce the differential pressure (?P).

Abstract: Provided is a work machine with which responsiveness of a hydraulic actuator can be improved when driving the hydraulic actuator through an electric lever-type operation device. A controller 100 further includes: an operation direction determining section 116 configured to determine operation directions of operation devices 2a and 2b; and a standby pressure switching command section 117 configured to output a standby pressure switching command to a first target pilot pressure correction section 112 or a second target pilot pressure correction section 113 which corresponds to a solenoid proportional valve that does not correspond to the operation direction from among first solenoid proportional valves 41a, 42a, 42b, 43a, 43b, and 44a and second solenoid proportional valves 41b, 42c, 42d, 43c, 43d, and 44b.

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: The construction machine includes: a body (9, 10); work equipment (15) having a plurality of swingable work elements (8, 11, 12); a plurality of hydraulic actuators (5, 6, 7) for driving the work equipment; a plurality of ground angle sensors (13a to 13d) for detecting the ground angles of the work elements; and an excavation support device (400) including an information processing device (100). The information processing device includes: a load information acquiring section (130) for acquiring load information including the load direction in the swing center of at least one of the work elements according to signals from the ground angle sensors; and a working point position calculating section (150) for calculating the position of the working point of the work equipment according to the signals from the ground angle sensors and the load information from the load information acquiring section.

Abstract: A work machine includes a plurality of actuators that drive a work device; a posture sensor that senses postural data about the work device; and a controller having a degree-of-proximity calculating section that computes a degree of proximity that is an index value indicating proximity between an intrusion prohibition region and the work device on the basis of positional data about the intrusion prohibition region and the postural data. A command section executes, when the proximity specified by the degree of proximity is closer than proximity specified by a degree-of-proximity threshold, operating area limiting control to decelerate at least one of the plurality of actuators such that an intrusion of the work device into the intrusion prohibition region is prevented. History of the data about the degree of proximity calculated at the degree-of-proximity calculating section is stored and the degree-of-proximity threshold is altered on the basis of the history data.

Abstract: Provided is a work machine with which responsiveness of a hydraulic actuator can be improved when driving the hydraulic actuator through an electric lever-type operation device. A controller 100 further includes: an operation direction determining section 116 configured to determine operation directions of operation devices 2a and 2b; and a standby pressure switching command section 117 configured to output a standby pressure switching command to a first target pilot pressure correction section 112 or a second target pilot pressure correction section 113 which corresponds to a solenoid proportional valve that does not correspond to the operation direction from among first solenoid proportional valves 41a, 42a, 42b, 43a, 43b, and 44a and second solenoid proportional valves 41b, 42c, 42d, 43c, 43d, and 44b.

Abstract: A wheel loader includes a working device, a lift cylinder 152 which is a hydraulic actuator that drives the working device, a hydraulic pump 220 that supplies hydraulic oil to the lift cylinder 152, a lift cylinder bottom pressure detector 252 that detects a pressure of the lift cylinder 152, a control valve 221 that controls the amount of hydraulic oil to be supplied from the hydraulic pump 220 to the lift cylinder 152, a vehicle acceleration detector 254 that detects a vehicle acceleration in a longitudinal direction, and a control device 240. The control device 240 determines whether the working device has started excavation, or not, based on the lift cylinder bottom pressure detected by the lift cylinder bottom pressure detector 252 and the vehicle acceleration detected by the vehicle acceleration detector 254.

Abstract: A hydraulic excavator including a controller that calculates the positional relationship between a bucket and a target surface and a display device that displays the positional relationship between the bucket and the target surface includes an actuator state sensor that detects the pressure of a hydraulic cylinder. The controller calculates the velocity of the bucket based on the position of a work implement and the operation amount of an operation device and changes the contents of informing by the display device according to the velocity of the bucket, the distance between the bucket and the target surface, and the pressure of the hydraulic cylinder. The display device displays the contents of informing changed by the controller.

Abstract: An object of the present invention is to provide a construction machine that allows easy and accurate calibration of a pressure sensor and enables accurate control of hydraulic actuators.

Abstract: A construction machine that can make a depressing force of a bucket during compaction work to be uniform without requiring an operator to perform a complicated operation is provided. A controller 18 determines whether or not compaction work is in progress, calculates a front distance R that represents a distance between a rotational pivot of a boom 4 and a predetermined position B in a back surface of a bucket 6, determines a target velocity of the bucket such that a velocity with which the bucket approaches a leveling target surface decreases with increasing values of the front distance, and, during the compaction work, notifies the operator of details of an operation of operation devices 9a and 9b for achieving the target velocity of the bucket or controls hydraulic actuators 4a to 6a so as to achieve the target velocity of the bucket.

Abstract: A hydraulic work machine is provided which can improve the finishing accuracy in a horizontally leveling work, a slope face shaping work and so forth by preventing sudden acceleration of an arm when the excavation load decreases suddenly. The hydraulic work machine includes an arm velocity-control valve device 22 capable of adjusting a meter-out opening of the arm cylinder independently of a first arm directional control valve 23. A controller 100 is configured to control, when correcting and increasing an operation amount instructed by the first arm directional control valve, the arm velocity-control valve device to decrease the meter-out opening of the arm cylinder in response to the increase of load pressure of the arm cylinder.

Abstract: A hydraulic excavator (1) provided with a controller (40) having a machine control section (43) that executes machine control for moving a work implement (1A) following a predetermined condition at the time of operation of operation devices (45a, 45b, and 46c) includes a level-of-intervention input device (96) that is operated by an operator. The controller includes a correction amount calculating section (43m) that calculates a correction amount of a level of intervention indicating a degree of intervention by the machine control in an operation of the work implement instructed through operation of the operation devices, based on an operation amount of the level-of-intervention input device. The machine control section executes the machine control to intervene in the operation of the work implement instructed through the operation of the operation devices at a level of intervention corrected based on the correction amount calculated at the correction amount calculating section.

Abstract: Provided is a work machine with which an operator can easily perform semi-automatic excavating shaping work at an intended excavation velocity.

Abstract: A work machine (1) includes a controller (40) having a notification control section (374) that exercises control as to whether to notify an operator of operation support information in accordance with a distance between a predetermined target surface, out of a plurality of discretionally set target surfaces, and a work implement (1A), the work machine including a current terrain profile acquisition device (96) that acquires a position of a current terrain profile, the controller including a target surface comparison section (62) that compares the position of the current terrain profile (800) with a position of the predetermined target surface (700) to determine a vertical position relationship between the current terrain profile and the predetermined target surface. The notification control section (374) changes content of the operation support information in accordance with a result of determination by the target surface comparison section.