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. 21, 1992
Filed:
Jan. 07, 1991
Claude Jouillat, Montigny-sur-Avre, FR;
Michel Brunet, Sainte-Colombe-la-Commanderie, FR;
Societe Technique de Pulverisation - S.T.E.P., Verneuil-Sur-Avre, FR;
Abstract
A prior art precompression metering pump which incorporates a differential piston forming part of the pump chamber inlet valve and its outlet valve is difficult to prime, especially in the case of metering paste products. In the improved pump there is disposed between the differential piston and the main piston of the pump a collar consisting of a ring from which project substantially axial tongues which are slightly inwardly inclined and each provided with a head. The collar moves inside the pump body so that normal operation proceeds as if it were not present. To prime the pump, however, the user depresses the collar until it contacts a step on the pump body. The tongues then bend so that their heads, interposed between the two pistons, move the latter apart (by a wedging effect or by a lever arm effect, or by a combination of the two). This is followed by mechanical opening of the pump chamber outlet valve whereby the air initially contained in the pump chamber escapes to the exterior.