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|1. (WO2017154220) CONSTRUCTION MACHINERY|
|Applicants:||HITACHI CONSTRUCTION MACHINERY CO., LTD.
Provided is construction machinery capable of reducing load torque during engine startup, even when the engine is stopped against a driver's will. A hydraulic shovel includes a control device (35) including a pump capacity control unit (37) and an unload control unit (38). When the engine speed of an engine (14) detected by an engine speed sensor (41) becomes equal to or lower than a low-speed engine speed N3 set in advance during the driving of the engine (14), the pump capacity control unit (37) controls a regulator device (20) so as to change the capacity of a hydraulic pump (16) to a minimum capacity. When starting the engine (14), the unload control unit (40) controls an unload valve (24) so as to be set to an open position.