| 摘要 |
<p>1,200,471. Fluid-pressure servomotor systems. KOEHLER-DAYTON Inc. July 26, 1967 [July 26th, 1966], No.27194/67. Heading G3P. [Also in Divisions F4 and G1] A fluid-pressure servo-controller suitable for regulating a valve in the nitrogen supply line to a cold-room (see Division F4) has a chamber 94 supplied from the refrigerant tank via a passage leading from inlet chamber 118. From chamber 94 the gas passes to the chamber behind diaphragm 88 via restricted orifice 101, and from this chamber a leakage path is defined by passage 107, passage 152 in shaft 110 and opposed angularly adjustable orifices 156, 157 Fig.9. A cam disc 160 is rotatably coupled to the indicator arm 62 of a Bourdon gauge by tab 163, and a lobe on the disc enters the space between the orifices 156, 157 when the arm 62 indicates the desired cold room temperature. The pressure thereby rises behind diaphragm 88 and the latter engages seat 117 and unseats vent poppet 125 from smaller seat 130 to allow main valve (20) to close. When arm 62 moves the cam lobe away from the orifices 156, 157, the pressure drops behind the diaphragm 88 and the latter moves leftwards to seat the vent poppet and connect chamber 118 to outlet 121 to open valve (20). The temperature probe is a phial containing carbon dioxide in gas and liquid form, the Bourdon tube filled with nylon, metal or p.t.f.e. or with a liquid (grease or mercury) or a settable material to prevent migration of the gaseous carbon dioxide. In other embodiments of the controller, guage could be replaced by a voltmeter, ammeter a speedometer for example. The controller could be reverse-acting and the disc 160 could co-operate with more than one pair of opposed orifices.</p> |
