| 摘要 |
<p>625,244. Fluid-pressure servomotor-control systems. VICKERS-ARMSTRONGS, Ltd., and CLARKE, T. F., and COLE, P. W., [Representatives of INGOLDBY, M. K.], SPAINK, J. H. ABBINK-, and SPENCER, A. June 9, 1939, No. 16963. [Class 135] A power transmission system, particularly for gun mountings, includes a hydraulic power amplifier unit, Fig. 1, whose sensitive control element 4 is driven by an electric motor, means being provided in association with the hunter control element of the unit for limiting its rate of displacement in either direction. The element 4 drives, through a shaft 5, a side member 3 of a differential whose centre member 2 drives a shaft 8. This shaft 8 is threaded to engage a fixed nut 10 and thus when rotated is also translated to control a valve 1 regulating the supply of pressure fluid from an inlet 16 to the cylinders 17. The resultant rotation of the angle box 18 drives an output shaft 11 at high speed, this shaft being connected to a shaft 12 which leads back to the differential in such manner that the member 2 has a displacement proportional to the speed of shaft 11 and also to the lag in the amplifier. As shown in Fig. 3, such displacement causes a corresponding displacement of a piston 22 working in a fluidfilled cylinder 23. The ends of the cylinder are interconnected by two passages 24, each fitted with a non-return valve 25, a needle valve 29, and a valve 26 which has a bore shaped as shown and which is rotated by a pin 28 on a rack 21 driven by the member 2. The two passages have their valves 25 and also the valves 29 oppositely arranged with respect to the cylinder, and the ports in valves 26 are also oppositely arranged so that when one valve is closing the other valve remains open for a time. A bleed hole 30 is formed in the piston 22. In use, fluid passes through one or the other of the passages 24 when the piston moves to the right or left of its central position, but at higher speeds of the amplifier both valves 26 become closed and the speed of the piston is thereby reduced. Thus the rate of displacement of the valves of the hunter gear is limited so that the acceleration of the output is controlled. Lag correction may be introduced, Fig. 4 (not shown), by a further differential between the follow-up motor and the spindle 4.</p> |
