Differential pressure switch
AssigneeDresser Industries, Inc.
InventorsRandall Goff, Leonard P. Delvecchio
Life of this patent
Estimating the term…
Abstract
A differential pressure module is secured in switching relation to the actuating plunger of an electrical switching mechanism. Comprising the differential pressure module are two piston/cylinder assemblies connected together in back-to-back configuration by secured cross members forming a floating yoke. Each of the assemblies includes a diaphragm in communication with a separate oppositely directed fluid inlet and through which a force differential effective from the separate forces acting in opposition to each other is applied via the yoke against the switch actuator. A cast body intervening between the assemblies defines the fluid inlets while maintaining the pressure of each isolated from the other.
Claims9
A pressure switch including an electrical switching mechanism, a pressure movable actuator for operating said switching mechanism between on-off positions, a range spring operatively effective to oppose pressure induced movement of said actuator, and a differential pressure unit comprising in combination:
- a. body means having a pair of separated fluid inlets in which to receive pressurized fluid from different sources, a first of said inlets communicating with a first fluid outlet opening in said body means and a second of said inlets communicating with a second fluid outlet opening in said body means;
- b. a pair of spaced apart diaphragm-piston assemblies supported with said body means intervening therebetween, one of said assemblies being exposed in pressure-tight relation to the first of said fluid outlet openings and the second of said assemblies being exposed in pressure-tight relation to the second of said fluid outlet openings;
- and
- c. a unitary force transmitting means concomitantly engaged by each of said diaphragm-piston assemblies for operably transmitting a pressure induced force against said actuator in opposition to said range spring correlated to the difference in pressures exerted against said assemblies by the different fluid pressures received at said inlets.
Dependencies are inferred from the claim text.