Patent ID: 9037356
Filing Date: 2015-05-19
Classification: E02F,F15B

Abstract:
1. A control device for a hybrid construction machine, comprising: a variable volume pump; a plurality of operation valves that control a flow of a working oil led to respective actuators from the variable volume pump; a neutral flow passage that leads the oil discharged from the variable volume pump to a tank when the operation valves are in a neutral position; a pilot pressure generating throttle provided in the neutral flow passage on a downstream side of the operation valves; a first pilot flow passage to which a pressure generated on an upstream side of the pilot pressure generating throttle is led; a regulator that performs control such that a tilt angle of the variable volume pump increases as an exerted pilot pressure decreases; an operating condition detector that detects an operating condition of the operation valves; a regenerative hydraulic motor rotated by the oil discharged from the variable volume pump; a power generator connected to the hydraulic motor; a main switch valve that leads the working oil discharged from the variable volume pump selectively to the operation valves or the hydraulic motor; a second pilot flow passage that leads a pilot pressure oil supplied from a pilot pressure source to the regulator; a pilot selection valve that connects the first pilot flow passage or the second pilot flow passage to the regulator selectively; a solenoid variable pressure reducing valve that is provided in the second pilot flow passage to be capable of variably controlling a pilot pressure led from the pilot pressure source and exerted on the regulator; and a controller that switches the main switch valve such that the oil discharged from the variable volume pump is led to the hydraulic motor and switches the pilot selection valve such that the second pilot flow passage communicates with the regulator when all of the operation valves are determined to be in the neutral position on the basis of a detection result from the operating condition detector.