HYDROSTATIC FLOW-AMPLIFIER

• Main Author: CYPHELLY I,CH
• Format: Patent
• Language: English
• Published: 22.10.1974
• Subjects: BLASTING; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR; FLUID-PRESSURE ACTUATORS; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; HEATING; HYDRAULICS OR PNEUMATICS IN GENERAL; LIGHTING; MECHANICAL ENGINEERING; SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; WEAPONS

1277641 Fluid-pressure servomotor systems I J CYPHELLY 18 June 1969 [27 June 1968; 30 Oct 1968] 30836/69 Heading G3P A fluid-pressure amplifier comprises a throttling disc 4, Fig.1, movable in response to adjustment of a valve means 10, 11 in a housing 9 to vary simultaneously the width of a gap 6 through which fluid is supplied from inlets 3 to an outlet port 13, Fig.2, and the width of a control gap 5 through which fluid from the inlets flows to the valve means. The hydraulic resistance of the gap 5 is greater than that of the gap 6 which has a labyrinthine seat 8 and the control to load flow ratio may be 100:1. In Fig.6, the load pressure area 8 is separated from the control pressure area 7 by a bellows 16 and a wall forming the control throttling seat 19 is located radially within an annular load throttling seat 14. In a modification, the control throttling seat consists of an adjustable screw so that a control member, such as a flapper valve, can completely close the load circuit. In Fig. 8, the lower face of the disc is divided by bellows 23 and 24 into an inlet pressure area 3 and an area 25 that is kept pressure free by a vent 21. Load pressure in the space 26 is led by a passage 27 to a compensating space 28 between bellows 16 and 22 so that the position of the disc is independent of load pressure. Since the feed pressure of line 1 is divided only as a function of the control pressure at 17 the arrangement may be used as a low output impedance pressure divider. In a modification, a single control pressure regulates a number of load pressures. Amplifiers similar to those of Figs.6 and 8 may be connected in series and be controlled by an electrically heated resistance wire (29), Fig.10 which varies the viscosity and hence the flow rate of fluid in a control bore.