| 摘要 |
<p>1,170,281. Fluid-pressure servomotor systems. DOWTY TECHNICAL DEVELOPMENTS Ltd. Feb.7, 1967 [Feb.16, 1966], No.6742/66. Heading G3P. An electro-hydraulic servo-valve comprises a main spool 23 controlling communication between inlet 14, work ports 21, 22 and exhaust 16, the spool having nozzles 31, 32 supplied from the inlet via restrictions 35, 36. Each nozzle cooperates with a spring-biased perforated diaphragm 37 supporting a coil 39 of an electromagnet 40 having a permanent magnet 42. The diaphragm chambers communicate with exhaust via passages 51, 52. The nozzle back pressures act on the axially outer faces of spool lands 25, 26 and the displacement of the spool is proportional to the current in either coil or to the difference. of the currents in the two coils.</p> |
