HYBRID CONSTRUCTION MACHINE

摘要

A hybrid construction machine includes first and second main pumps, first and second supply passages, first and second circuit systems, a hydraulic motor, a motor generator, an assist pump, a joint passage connected to the assist pump and branched off, first and second logic valves, a switching valve disposed in the other branch passage and switchable to a state where the assist pump is connected to the second supply passage on the upstream side of the second logic valve and a state where the second main pump is connected to the hydraulic motor, and a check valve. A poppet diameter of the first logic valve is smaller than that of the second logic valve.

主权项

1. A hybrid construction machine, comprising:
a first main pump and a second main pump; a first circuit system connected to the first main pump via a first supply passage; a second circuit system connected to the second main pump via a second supply passage; a hydraulic motor connected to the second main pump; a motor generator adapted to be rotated by a drive force of the hydraulic motor; an assist pump adapted to be rotated by a drive force of the motor generator; a joint passage connected to the assist pump and branching off at an intermediate position into one branch passage and other branch passage; a first logic valve disposed between the one branch passage and the first supply passage; a second logic valve disposed in the second supply passage; a switching valve disposed in the other branch passage and switchable to a state where the assist pump is connected to the second supply passage on the upstream side of the second logic valve and a state where the second main pump is connected to the hydraulic motor; and a check valve provided downstream of the switching valve in the other branch passage and permitting only a flow from the assist pump to the second logic valve, wherein a poppet diameter of the first logic valve is smaller than a poppet diameter of the second logic valve.