| 摘要 |
An energy recovery control circuit that requires less space for installation of an energy recovery system and costs thereof is provided. An energy recovery control circuit 40 includes an recovery control valve block 20 for recovering boom energy. The recovery control valve block 20 is provided between an output port 38 of a main control valve 33 and a parallelly arranged first boom cylinder 17c1 and second boom cylinder 17c2. The recovery control valve block 20 has a block main body 42, in which a plurality of valves, such as a main spool 43, are incorporated. A plurality of control characteristics concerning recovery of energy are consolidated in the main spool 43. The recovery control valve block 20 has functions such that the potential energy of the boom at a raised position is recovered from the first boom cylinder 17c1 and accumulated in an accumulator 41 during boom-down operation and that the oil accumulated in the accumulator 41 is directly released to the first boom cylinder 17c1 and the second boom cylinder 17c2 during boom-up operation. |
