| 摘要 |
1,056,416. Fluid-pressure servomotor systems. McNAMEE INDUSTRIES PTY Ltd. July 8, 1964 [July 22, 1963], No.28198/64. Heading G3P. A reversible electric motor (not shown) controlled by an input signal, e.g. a temperature or pressure, turns an internally threaded sleeve 11, through a flexible coupling 23, whereby the sleeve moves axially to displace a rod 26 and spool valve 31 to connect a hydraulic piston and cylinder motor (not shown) to pressure or exhaust, the consequent movement of the motor, which may operate a bank of baffles in a boiler flue, giving a feedback motion through a flexible wire 40 passing round a disc 49 secured to a disc 19 and a threaded sleeve 14. The sleeve 14 is held against axial movement so that its rotation returns the outer sleeve 11 to its original, neutral, axial position to stop the motor. The disc 49 may be cam-shaped to provide a non-linear characteristic. Alternatively, for linear operation, the wire 40 may be passed once round the disc 19 and continue over a pulley 42 to a fixed anchorage and carry a counterweight 43 or spring. The sleeve 11, which may also be manually operated, is limited in its rotation relatively to the sleeve 14 by a pin 50 coacting with an arcuate cut-out 51 in a disc 22, and the discs 19, 22 may be graduated for observation. The spool valve shown is three-ported for control of a single-acting motor but it may be four-ported for a doubleacting motor. The wire 40 may be replaced by linkage, and an air operated valve may replace the spool valve 31. The rod 26 is of triangular cross-section to allow passage of oil and an oil reservoir 45 is provided for lubrication of the screw threads. |
