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:
Jul. 24, 1990
Filed:
Nov. 10, 1988
Kenneth L Miller, Indianapolis, IN (US);
SCM Metal Products, Inc., Cleveland, OH (US);
Abstract
The present invention relates to a dispensing device comprising a housing containing at least three pressure chambers. The upper pressure chamber being separated from the middle pressure chamber by a reciprocating upper piston composed of a head and a stem. A lower piston is reciprocally positioned between the middle and lower pressure chambers such that pressurization of the lower pressure chamber exerts upward pressure on the lower piston and pressurization of the middle pressure chamber exerts downward pressure. The lower piston is fixed to a reciprocating rod which has a dispensing rod tip. The dispensing rod tip is slidably situated within a dispensing tube which has a tube opening for introduction of a dispensible material therethrough. The dispensing rod tip is reciprocatable between an upward, downward and intermediate position. In its upward position, a tube opening is non-occluded, thereby allowing the dispensible material to enter a dispensing tube. In its downward position, the tube opening is occluded and positive pressure is exerted on the dispensible material within the dispensing tube. In its intermediate position, the tube opening is occluded without exerting positive pressure on any dispensible material within the dispensing tube. The upward movement of the dispensing rod tip from the downward position to the intermediate position creates negative pressure in the dispensing tube which snuffs back any dispensible material within the dispensing tube.