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:
Jul. 20, 1993
Filed:
Jan. 22, 1992
John E Lair, Decatur, IL (US);
James F Delahunty, Decatur, IL (US);
Lawrence F Luckenbill, Decatur, IL (US);
Richard J Holliday, Decatur, IL (US);
A. W. Cash Valve Manufacturing Corporation, Decatur, IL (US);
Abstract
In order to prevent contamination of a fluid source and to ensure drainage of a sill cock or the like, a detachable check valve back flow preventer for installation between a fluid inlet line and a fluid outlet line is provided. A housing with means for fastening the device to a fluid inlet line at one end of the housing and for connecting a fluid outlet line at the other end of the housing is provided. The housing has a central cavity within the housing. An inlet line drain valve is located within the housing between the central cavity and the fluid inlet line to provide for the drainage of fluid from the fluid inlet line to the fluid outlet line end of the housing when the fluid outlet line is not connected to the back flow preventer. A second valve is located within the housing between the central cavity and the fluid inlet line to control flow of fluids between the fluid inlet line and the central cavity. A third valve is located within the housing between the central cavity and the fluid outlet line to control flow between the central cavity and the fluid outlet line. In a second aspect of this invention a fourth valve is located within the housing between the central cavity and the drainage flow path to control flow between the central cavity and the venting means. This second aspect can be utilized in conjunction with the above three valves or in combination with only the second and the third valve.