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:
Sep. 28, 1999
Filed:
Sep. 24, 1996
Mark D Dalhart, Mason, OH (US);
Hydro Systems Company, Cincinnati, OH (US);
Abstract
A purge valve for use with a chemical select valve comprises, in a preferred embodiment, an enlarged chamber in the vacuum impelled feed line to the select valve. The chamber is formed by resilient walls, collapsible upon vacuum operation to draw chemical into a venturi line where it is mixed with water and dispensed. The walls do not fully collapse and provide passages for chemical flow. Upon vacuum interruption, the chamber walls expand, returning the chamber to its larger volume and drawing chemical back upstream from common passages in the select valve. Another chemical can then be selected without contamination of the preceding chemical in the common passages.