Hitachi Construction Machinery Co., Ltd.

Masatoshi Morikawa

Shinji Nishikawa

Hiroaki Tanaka

Shinya Imura

Akihiro Narazaki

A work machine includes a work implement provided to a machine body, a posture sensor that senses posture information regarding the work implement, a controller configured to compute a specific position of the work implement on the basis of the posture information, set a limited area that the work implement is prohibited from entering, compute a movable distance as a distance between the limited area and the specific position of the work implement, and limit operation of the work implement according to the movable distance to prevent the work implement from entering the limited area, and an input device for inputting to the controller input information input by an operation of an operator. The controller includes a storage device that stores boundary information related to a plurality of different kinds of shapes of limited area boundaries, and the controller is configured to select one from among the plurality of kinds of shapes of limited area boundaries included in the boundary information, on the basis of the input information input from the input device, and set a limited area boundary of the selected kind of shape.

Work machine

An object of the present invention is to provide a work machine that is capable of flexibly setting an entry-prohibited area for a work device according to an operator's intention. To achieve this, a controllersets, as a first position, the position of a work toolthat is located when a setting switchis operated, and sets, as a second position, the position of the work toolthat is located when the setting switchis operated after the setting of the first position. Further, the controllersets, as a boundary surface of an entry-prohibited area, a planethat passes through a first reference point A and a second reference point B and that is perpendicular to a ground contact surface of a lower track structure. The first reference point A is one of a plurality of reference pointsL andR on the work toollocated at the first position, the plurality of reference pointsL andR being preset on the work tool. The second reference point B is one of the plurality of reference pointsL andR on the work toollocated at the second position.

To control a rate of increase of a delivery flow rate of a pump for a swing operation in response to a moment of inertia and an operation amount and to achieve both energy efficiency and operability with respect to the swing operation, a work machine including a swing structuredisposed on an upper portion of a track structure, a work implementdisposed in the swing structure, a swing motor, a hydraulic pump, a regulator, a directional control valve, and an operation devicefurther includes: a target maximum flow rate calculation sectionconfigured to calculate a target maximum flow rate Qmax of the pump to correspond to a swing operation amount Ps; a flow rate rate-of-increase calculation sectionconfigured to calculate a rate of increase dQ of a command flow rate of the hydraulic pumpon a basis of the moments of inertia of the swing structureand the work implementand the swing operation amount Ps; a command flow rate calculation sectionconfigured to calculate a command flow rate Q(t) on a basis of the rate of increase dQ with the target maximum flow rate Qmax set as an upper limit; and an output sectionconfigured to output a command signal Sf to the regulatorcorresponding to the command flow rate Q(t).

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Tsukuba, Japan

Masatoshi Morikawa