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:
Mar. 11, 2003
Filed:
Apr. 04, 2001
David Jonathan Chalk, Slatington, PA (US);
Donald Earl Thompson, Schnecksville, PA (US);
David John Farese, Riegelsville, PA (US);
Air Products and Chemicals, Inc., Allentown, PA (US);
Abstract
A reciprocating pump includes a housing, a piston slideably mounted within the housing for a reciprocating movement, a shaft connected to the piston and adapted for reciprocating movement concurrently with the piston, an inlet valve, a discharge valve, and an interstage valve means. A first chamber on one side of the piston is in fluid communication with an inlet and a second chamber on the opposite side of the piston is in fluid communication with a discharge, and the first and second chambers are in fluid communication. At least part of the shaft is in the second chamber. The interstage valve means, which controls the fluid flowing from the first chamber to the second chamber, is closed during a suction stroke and is open during a compression stroke.