PNEUMATISCHE REGELAAR.

摘要

1300620 Fluid-pressure servomotor systems FISHER CONTROLS CO INC 18 May 1970 [25 July 1969] 24003/70 Heading G3P A pneumatic controller has a rotary input responsive to pressure or liquid level acting on an arcuate flapper 16 which co-operates with a nozzle 18 to give a pressure output P o via an amplifier 46. The nozzle is rotatable about an axis C to vary the gain and is movable by a lever 28 connected via a spring 40 to a feedback bellows 34 and a reset bellows 36. The lever 28 is pivoted about an axis B on a lever 26 which is pivoted about the input axis A and provides for adjustment of the set point. Alternatively the input may act on lever 26 and the set point is then adjusted by rotation of the shaft 14. In modifications the back pressure in a nozzle co-operating with a flapper on the shaft 14 actuates a bellows to move a pointer over a scale and a feedback bellows acts on the centre of a wire fixed at one end and connected to the lever 28 at the other to give an output which is proportional to the square root of the input.