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:
Dec. 07, 1993
Filed:
Apr. 12, 1993
Wilfried Baumgarten, Pattensen, DE;
Paul Troester Maschinenfabrik, Hanover, DE;
Abstract
A screw extruder has a feed roller which is parallel to and spaced laterally from the screw, a hopper feeds the material to be extruded to the screw and feed roller and to the space between them. A knife scrapes material from the feed roller to keep it clear. In one embodiment, the knife is pivotally supported by a knife holder disposed below the feed roller and is pulled against the feed roller by a spring-loaded link which is pivotally attached to a median portion of the blade. In another embodiment, the knife is a flexible spring blade. A protuberance on a knife-holding plate limits flexing of the blade by pressure of material in the space between the screw and the feed roller. In a further embodiment, a photo-cell scans a rear side of the feed roller and controls a servo-motor for drawing the knife against the feed roller.