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.
Patent No.:
Date of Patent:
Nov. 23, 1976
Filed:
Sep. 26, 1975
Fred E Watkins, Houston, TX (US);
Camco, Incorporated, Houston, TX (US);
Abstract
A fluid injection valve for use in a well tubing having an opening therein in which the valve controls the flow of fluid flowing between the outside of the tubing and the inside of the tubing through the opening. A spring-loaded relief valve element yieldably closes a port in the valve against the flow of fluid and a closed flexible pressurized chamber is provided with one end being movably positioned against the valve element. The exterior of the chamber is exposed to the valve outlet pressure so that in the event that the outlet pressure drops below a predetermined amount, the chamber will expand and act against the valve element to close the valve. The chamber may be a bellows and the cross-sectional area of the chamber is preferably greater than the cross-sectional area of the port to provide a closure force sufficient to overcome a hydrostatic head outside of the tubing.