| 摘要 |
PURPOSE:To perform multiple-stages forming work within one stroke of a slide by incorporating mechanisms for converting pneumatic pressure to oil pressure to pressure sources for upper and lower cushion devices with a plurally duplicated constitution and making the pressure of the respective hydraulic mechanisms individually and freely adjustable. CONSTITUTION:The pressure of an air source 87a with an upper cushion device 19 is acted always to a feed tank 93 via a solenoid valve SOL1 and the pressure thereof is supplied to the inside of the pressure increasing chamber 91 of a booster 91. When solenoid valves SOL1, 2, 3 are energized, the booster 91 operates to supply the oil in the chamber 91b to the 2nd fluid pressure chamber 51 of the upper cushion device 19. When the pressure in the chamber 51 is increased by the rise of a piston 47, the pressure is exerted through a check valve CV1 to the chamber 91b. The oil is fed from the chamber 91b to the chamber 51 through a flow rate control valve FCV and the solenoid valve SOL3 and the piston 47 is lowered to perform knock-out. The pressure for a lower cushion device 53 is controlled by supplying the oil to the 3rd fluid pressure chamber 79 by means of an air source 87b and an oil tank 95. |
