| 摘要 |
PURPOSE: To economically operate an adjusting part, control part and driving part by providing a plurality of piston/cylinder units is a press and communicating upper and lower cylinder chambers with a hydraulic device. CONSTITUTION: When the pistons 5 of a plurality of piston/cylinder units 2, 3 are lowered, the pressure medium within lower cylinder chambers 8 is sent to a first hydraulic device 10 and further reaches upper cylinder chambers 7. Then the first hydraulic device 10 is driven as a hydraulic motor, and further the pressure medium is transmitted to a second hydraulic device 12 functioning as a variable hydraulic pump. During the lowering movement of a ram 1, additional filling of the pressure medium to a hydraulic accumulator 18 is executed through a third hydraulic device 20. Deforming, cutting or the like of a workpiece is executed by energizing the inside of the upper cylinder chambers 7 by an additional pressure. Thereafter, the pressure medium is sent from the upper cylinder chambers 7 to the lower cylinder chambers 8 to move the ram 1 to a starting position again. |
