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:
Apr. 22, 1980
Filed:
Feb. 08, 1979
Ernst Kuhlen, Willich, DE;
Pierburg GmbH & Co., KG, Neuss, DE;
Abstract
A diaphragm pump operated by vacuum pressure and having a switching arrangement to control the continuous alternations between the intake stroke caused by vacuum pressure and the working stroke caused during venting by a spring after the end of each stroke. The switching arrangement consists of a crack-open valve between vacuum pressure chamber and a space continually connected to atmosphere, and a plunger, fastened to the diaphragm; the length of the plunger is variable through a spring clutch. The special action of the switching arrangement is based on the fact that the plunger requires a larger force for cracking the valve than afterwards for keeping it open. This is accomplished by having a differential pressure, act in the closing direction on the valve, and eliminating this force after opening, causing the spring-loaded plunger to extend to its full length and to keep open the valve during the entire working stroke of the diaphragm.