HYBRID CONSTRUCTION MACHINE

摘要

The objective of the present invention, in a hybrid construction machine, comprises a hydraulic motor and an electric motor as a driving source of a rotor, and provides a hybrid construction machine which maintains an operator′s good operating condition during a complex rotational motion. The hybrid construction machine of the present invention comprises: a rotor (50); a hydraulic pump (1); a hydraulic rotating motor (3) to drive the rotor (50) with operating oil from the hydraulic pump (1); an electric rotating motor (14) to drive the rotor (50) along with the hydraulic rotating motor (3); a boom cylinder (16) which occasionally works simultaneously with the rotor (50) and is driven by the operating oil from the hydraulic pump (1); a first direction control valve (28) to control a flow of pressure oil supplied from the hydraulic pump (1) to the hydraulic rotating motor (3); a second direction control valve (29) to control a flow of returning oil from the hydraulic rotating motor (3); a controller (13) to make it impossible for the second direction control valve (28) to work when a boom cylinder (16) works simultaneously with the rotor (50); and electromagnetic pressure-reducing valves (30, 31).