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:
Aug. 20, 1985
Filed:
Sep. 27, 1982
John H Olsen, Vashon, WA (US);
Sigurd C Mordre, Dockton, WA (US);
Flow Industries, Inc., Kent, WA (US);
Abstract
A piston and a cylinder within a pump housing cooperate with the inner walls of the housing to form a high-pressure reservoir surrounding the cylinder to provide a continuous compressive force thereon to prevent tensile stresses in the cylinder during pumping operations to prevent failure of the cylinder due to metal fatigue. A check valve between the cylinder and the reservoir permits high-pressure fluid to flow from the cylinder into the reservoir during pumping operations to maintain substantially the maximum cylinder pressure within the reservoir. The cylinder further includes therein an inlet with an associated check valve. Stationary seals in the pump use the high pressures in the cylinder and the reservoir for producing the sealing forces necessary to prevent leakage. The primary piston seal consists of a long, controlled clearance gap which permits a small leakage but has only minor contact and thereby low sliding stresses and a long life.