Abstract: A hydraulic drive apparatus includes a boom flow rate control valve, a target boom cylinder speed calculation part, a pressing force calculation part, a correction part, and a boom flow rate operation part. The target boom cylinder speed calculation part calculates a target boom cylinder speed for making the construction surface by the bucket closer to the target construction surface. The pressing force calculation part calculates the pressing force by which the bucket is pressed against the construction surface, based on the cylinder thrust of the boom cylinder and the center-of-gravity position information on the center-of-gravity position of the work device. The correction part corrects the target boom cylinder speed to make the deviation between the target pressing force and the calculated pressing force closer to 0. The boom flow rate operation part operates the boom flow rate control valve to provide the corrected target boom cylinder speed.

Abstract: A hydraulic drive apparatus includes a boom flow rate control valve, a target boom cylinder speed calculation part calculating a target boom cylinder speed for making a construction surface by a bucket closer to a target construction surface based on the cylinder speed of a boom cylinder and the like, and a boom flow rate operation part. The boom flow rate operation part operates the boom flow rate control valve to make a boom cylinder supply flow rate be a target supply flow rate corresponding to the target boom cylinder speed when the target boom cylinder speed direction coincides with a cylinder thrust direction, and operates the boom flow rate control valve to make the boom cylinder discharge flow rate be a target discharge flow rate corresponding to the target boom cylinder speed when the target boom cylinder speed direction is opposite to the cylinder thrust direction.

Abstract: A hydraulic drive apparatus includes a boom flow rate control valve, a target boom cylinder speed calculation part, a pressing force calculation part, a correction part, and a boom flow rate operation part. The target boom cylinder speed calculation part calculates a target boom cylinder speed for making the construction surface by the bucket closer to the target construction surface. The pressing force calculation part calculates the pressing force by which the bucket is pressed against the construction surface, based on the cylinder thrust of the boom cylinder and the center-of-gravity position information on the center-of-gravity position of the work device. The correction part corrects the target boom cylinder speed to make the deviation between the target pressing force and the calculated pressing force closer to 0. The boom flow rate operation part operates the boom flow rate control valve to provide the corrected target boom cylinder speed.

Abstract: A safety apparatus of a work machine includes: obstacle sensors provided in the upper revolving body; a revolving angle detector; an upper-side coordinate position calculation section that calculates an upper-side coordinate position of the obstacle in the upper-side coordinate system using the upper revolving body as a reference; a lower-side judgment area setting section that sets a lower-side judgment area in the lower-side coordinate system using the lower traveling body as a reference; a coordinate transformation section that transforms one of the upper-side coordinate position and the position of the lower-side judgment area into the other coordinate system to unify the coordinate system; a lower-side approach judgment section that judges whether an obstacle exists within the lower-side judgment area in the unified coordinate system; and a safety operation command section that outputs a safety operation command based on the judgment result.

Abstract: An obstacle detection device capable of appropriately setting an area for detecting an obstacle in the vicinity of a machine body of a construction machine in consideration of the state of inclination of the construction machine with respect to its surrounding ground area includes an inclination information acquisition section to obtain inclination information of the machine body with respect to a surrounding ground area in the vicinity of the construction machine, and an area setting section to set a monitoring area for detecting an obstacle, and to modify the monitoring area according to the inclination information.

Abstract: A hydraulic drive apparatus includes a boom flow rate control valve, a target boom cylinder speed calculation part calculating a target boom cylinder speed for making a construction surface by a bucket closer to a target construction surface based on the cylinder speed of a boom cylinder and the like, and a boom flow rate operation part. The boom flow rate operation part operates the boom flow rate control valve to make a boom cylinder supply flow rate be a target supply flow rate corresponding to the target boom cylinder speed when the target boom cylinder speed direction coincides with a cylinder thrust direction, and operates the boom flow rate control valve to make the boom cylinder discharge flow rate be a target discharge flow rate corresponding to the target boom cylinder speed when the target boom cylinder speed direction is opposite to the cylinder thrust direction.