The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Dec. 19, 2000

Filed:

Jun. 01, 1999
Applicant:
Inventor:

Michael D McNeely, Katy, TX (US);

Assignee:

Tyco Flow Control, Inc., Houston, TX (US);

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G05D / ;
U.S. Cl.
CPC ...
137491 ;
Abstract

A pilot operator and a relief valve are provided in the same housing. The pilot-operating mechanism is contained partially within the main closure element of the valve and partially within the valve cap. Inlet pressure to the valve is communicated to the pilot via an access passage extending through the main closure element. In response to high-pressure flow from the inlet, a pilot piston moves a spacer rod through the passage and into engagement with a spring-loaded vent closure. The piston-induced movement of the rod opens the vent to relieve the pressure behind the main closure element, which in turn permits the main closure element to open and relieve the inlet pressure through the valve outlet. Opening of the main closure element terminates flow through the access passage. When the inlet pressure is sufficiently reduced, the pilot piston is unseated by the spring force re-opening the access passage to allow the pressure behind the main closure element to increase and close the main closure element. A back-flow-prevention assembly carried in the main closure element prevents reverse flow of fluids from the outlet to the inlet when the outlet pressure exceeds the inlet pressure.


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