Hydraulic remote indicating or control apparatus


864,295. Pressure gauges; indicating apparatus. ARIC Ltd. Feb. 21, 1958 [Feb. 22, 1957], No. 6073/57. Classes 106 (2) and 106 (4). [Also in Groups XIII and XX] Hydraulic remote indicating apparatus in which an indicator is actuated by an expansion chamber connected through an operating tube to a device which varies the volume of liquid filling the expansion chamber comprises a first compensating expansion chamber connected to a compensating tube adjacent the operating tube, to correct fully for temperature changes in the vicinity of the tube and partially for temperature changes in the vicinity of the expansion chambers, a second compensating expansion chamber to complete the correction for temperature changes in the vicinity of the expansion chambers, and independent adjustments for the two expansion chambers. In the thermometer shown, the liquid-filled bulb 21 is connected by a capillary tube 19 to a bellows 1, the expansion of which moves a rod 26 in a bearing 12. This rod carries a pivoted bellcrank 13 having a fulcrum 27, bearing on an arm 15, and an arm 28 against which is held, by a spring 23, a roller 29 on the arm of a bellcrank 10 which actuates a pointer 11 through a toothed sector 31 and pinion 32. Correcting movements are applied to the lower end of the bellows 1, the capillary tube 19 being looped at 25 to provide flexibility. The end of the bellows is attached to a pivoted arm 8 to which is coupled at an adjustable point a bellows 2 connected to a capillary tube 20 adjacent the tube 19. This compensates for changes in ambient temperature of the capillary and partly compensates for changes in temperature of the bellows 1. The compensation for the latter is completed by a bellows 3 having one end fixed and coupled at the other to an adjustable point on a lever 9 to which the bellows 2 is coupled. The pivoted lever 15 is coupled to a bi-metallic strip 14 which adjusts the fulcrum 27 to provide a second order correction for the fact that the volume of liquid in the bellows changes with temperature. The bellows may be replaced by Bourdon tubes.




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    CN-104245013-ADecember 24, 2014普雷斯弗雷克斯股份公司Compensated capillary indicator
    CN-104245013-BAugust 24, 2016普雷斯弗雷克斯股份公司补偿的毛细管指示器