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. 12, 1997
Filed:
May. 16, 1995
Horst Fritsch, Leonberg, DE;
Lewa Herbert Ott GmbH & Co., Leonberg, DE;
Abstract
A hydraulically driven membrane pump, particularly a high pressure membrane pump, having a membrane which is held on its edges by a clamp between a pump housing and a pump cover, which membrane separates a pumping space from a hydraulic compression space, and may particularly be a metal membrane. A hydraulic membrane drive in the form of a reciprocating displacement piston is slidably mounted in a cylindrical bore in the pump housing, which piston is disposed between the compression space and a reservoir space for the hydraulic fluid. A leak replenishment device including a snuffle link in the form of a connecting channel between the compression space and the reservoir space, which snuffle link is normally closed off by an underpressure-controlled spring-loaded snuffle valve. The snuffle link between the compression space and the reservoir space is controlled via the position of the piston, wherewith the piston serves as the slide element of a slide valve which blocks the snuffle link between the compression space and the reservoir space, at least at the beginning of the suction stroke of the piston, and only opens the link when the piston has been retracted through a part of its suction stroke.