| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a circuit structure of a hydraulic jack, which allows operation to be performed by electric control without using a throttle valve and allows hydraulic energy while a lifted object is supended to be effectively recovered as electric energy. <P>SOLUTION: The circuit structure of the hydraulic jack, which includes a hydraulic cylinder 3 and which hoists a lifted object W to be lifted by supplying hydraulic oil to the lower chamber 3a of the hydraulic cylinder 3 and extending a piston rod 2 and suspends the lifted object W by supplying the hydraulic oil to the upper chamber 3b of the hydraulic cylinder 3 and contracting the piston rod 2, includes: a power generator 17 that rotates by the hydraulic oil discharged from the lower chamber 3a while the lifted object W is suspended; a capacitor 18 accumulating electric energy generated by the power generator 17; and a constant-speed controller 19 for lowering the lifted object W at a constant speed by controlling capacitance of the capacitor 18 so as to change a power generation load of the power generator 17. <P>COPYRIGHT: (C)2012,JPO&INPIT |
