| 摘要 |
<p>1,236,861. Fluid bi-stable units. R. METIVIER. 23 Oct., 1969 [31 Oct., 1968], No. 51937/69. Heading G4R. [Also in Divisions F2 and G3] A bi-stable pneumatic valve unit 1, which per se can be used to provide signals at either one of two output lines 16 and 17 or which in combination with loop lines 18, 35 and 19, 41 can function in the manner of an oscillator, comprises a single input line 8, a freely movable piston 9, two freely movable flap valves 12 and 13, two exhaust lines 21 and 22, two control ports 29 and 31, and two actuators 23 and 24 each of which has associated therewith a diaphragm 25, 26. Upon applying a pressure to line 8, the piston 9 is caused to move to, say, block passage 11 as a result of which a signal is produced at output line 16 and flap 12 is urged to close passage 14 leading to exhaust 21. Subsequently, if actuator 23 is caused to move inwardly, flap 12 is unseated and line 16 opened to exhaust 21. The resulting differential created across piston 9, in consequence of the relatively restricted communication between chambers 2a and 3, causes the piston to move in a direction to close passage 10. Accordingly, output 16 remains vented whilst output 17 is pressurized by virtue of its communication with input 8. If now actuator 24 is caused to move inwardly, piston 9 will move to close passage 11 and the valve will be returned to its first state. Operation of actuators 23 and 24 may be achieved by mechanical, hydraulic or electrical means.</p> |
