GB1377892A - Pulsator for hydraulic systems controlling actuating mechanisms - Google Patents

Abstract

1377892 Fluid regulation EXPERIMENTALNY NAUCHNO-ISSLEDOVATELSKY INSTITUT KUZNECHNO-PRESSOVOGO MASHINOSTROENIA 9 Feb 1973 [14 Feb 1972 21 Feb 1972 28 March 1972] 6598/73 Heading G3H [Also in Division F2] Apparatus for producing hydraulic pulses comprises a main valve 2 which opens and closes automatically to permit and prevent the discharge to a drain 10 of high-pressure liquid delivered to a chamber 4 by a pump 18 via line 17, thereby producing hydraulic pulses in the chamber 4 and thus in an actuating mechanism, e.g. of a press, via a line 19. The valve 2 is biased to an open position by pressure liquid delivered through non- return valve 20 into chamber 5 beneath a piston 3, the chamber 5 being connectible to the drain 10 via a pilot valve 25 and throttle 23, and is biased to its closed position by a pneumatic pressure delivered to a chamber 13 above a piston 14 via change-over valve 31, non-return valve 32 and reducing valve 33. With the valves 2 and 25 in the positions shown and the valve 31 moved to communicate pneumatic pressure to the chamber 13, the pressure in chamber 5 causes the valve 2 to open, thereby connecting the chamber 4 to drain and opening the valve 25 mechanically via rods 12, 15, 28. The consequent drop in pressure in chamber 5 causes closure of the valve 2 whereby the valve 25 is closed and the pressures in chamber 4 and 5 build up again ready for the next cycle. The pressure of the pulses is adjustable by the reducing valve, and the pulsation frequency is adjustable by the throttle 23.