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. 19, 1989
Filed:
Jan. 05, 1988
William H Zebuhr, Nashua, NH (US);
American Thermal Corporation, Nashua, NH (US);
Abstract
A fluid-driven pump (10) includes a drive-inlet-valve assembly (54) that alternately directs the flow of cold pressurized water from a pressurized-water inlet (12) into alternate drive cavities (46a and b). Outlet valves (60a and b) control flow out of the drive cavities (46a and b). The resulting reciprocation of piston heads (36a and b) draws hot water in through a pump inlet (16) and out through a pump outlet (18). A valve operating mechanism driven by the piston heads' reciprocation causes both the drive outlet valves (60a and b) to close before the drive-inlet-valve assembly (54) changes its state to redirect flow of pressurized cold water from the cold-water inlet (12). The drive-inlet-valve assembly (54) is provided with a pilot-valve member that permits the drive-inlet-valve assembly (54) to be operated with a relatively low force and without introducing excessive shock and noise.