Hitachi Construction Machinery Co., Ltd.

Ryuu Narikawa

Kouji Ishikawa

Shiho Izumi

Shuuichi Meguriya

Tarou Akita

Daito Sakai

Shinya Imura

Masamichi Ito

Takahiko Kurose

A work machine () having a controller () that can perform area limiting control, the work machine further includes a machine control ON/OFF switch () that alternatively selects an ON position permitting execution of the area limiting control and an OFF position prohibiting execution of the area limiting control. The controller () has an engine control section () that performs automatic idling control when a predetermined period of time (T1) has elapsed after a point in time when all of operation levers () have attained a neutral state. The engine control section () is configured to execute the automatic idling control during when the switch () is in the OFF position and not to execute the automatic idling control during when the switch () is in the ON position.

Hydraulic excavator with area limiting control function

A hydraulic excavator () is provided with a controller () including an actuator control section () which, when an operation device () is operated, controls at least one of a plurality of hydraulic actuators () in accordance with the velocities of the plurality of hydraulic actuators () and a predetermined condition. The controller () determines, based on a sensed value from a posture sensor (), the direction of a load exerted on an arm cylinder () due to the weight of an arm (), outputs, upon determining that the direction of the load is opposite to a driving direction of the arm cylinder (), a second velocity Vamtto the actuator control section (), and outputs, upon determining that the direction of the load is the same as the driving direction of the arm cylinder (), a third velocity Vamtto the actuator control section ().

Work machine

Provided is a work machine that is equipped with a control unit that executes area limiting control with respect to a work device. The control unit includes: a position computing section that calculates the position, on an operation plane, of the forward end (first reference point) of a bucket and the rear end (second reference point) of the bucket; and a first distance computing section that calculates the distances in the operating plane from the first reference point and the second reference point to the target face A to be controlled. When the smaller one of the two distances is equal to or lower than a threshold during area limiting control, the control unit corrects an operation signal output from an operation lever device so as to reduce the operating speed of a hydraulic actuator that is a control target of the operation signal.

A work machine includes: a multi-joint type work implement; a plurality of hydraulic actuators driving the work implement; an operation device outputting an operation signal to the plurality of hydraulic actuators; a storage section storing a target configuration defined by connecting a plurality of target surfaces; a control object surface selection section that in the case where a control point set at a claw tip of a bucket is under the target configuration, uses a target surface closest to the control point on the target configuration as a control object surface; and a target operation control section that controls the plurality of hydraulic actuators such that the operational range of the control point is limited to the control object surface and a region above the same in the case where an excavation operation is input from an operator via the operation device.

A work machine has a controller which has an area limiting control section correcting the pilot pressures of pilot lines, a regeneration control section adjusting the flow rate of the hydraulic fluid caused to flow from a tank side line of an arm cylinder into a pump side line thereof between zero and a predetermined upper limit value, and a regeneration control switching section that issues an order to the regeneration control section to set the predetermined upper limit value to a first set value when the function of the area limiting control section is invalid and that issues an order to the regeneration control section to set the predetermined upper limit value to a second set value that is smaller than the first set value when the function of the area limiting control section is effective.

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Mito, Japan

Ryuu Narikawa