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:
Oct. 31, 1989
Filed:
Apr. 01, 1988
Herbert Ocker, Leonberg, DE;
Gerhard Weihrich, Illingen, DE;
Werner & Pfleiderer GmbH, Stuttgart, DE;
Abstract
A degassification device for a screw extruder which processes plastic material in which the extruder has a hollow housing and an extruder screw rotatable in the housing, the degassification device having a pair of degassification screws disposed adjacent to the extruder screw for rotation about axes parallel to the axes of rotation of the extruder screw. A housing headpiece accommodates the degassification screws and is in communication with the extruder housing such that gas and vapor produced in the extruder housing can flow radially therefrom into the housing headpiece for discharge therefrom. The degassification screws have threads which interengage one another and they are driven in the same direction of rotation. The housing headpiece has adjacent longitudinal bores which overlap one another and respectively receive the degassification screws therein with their threads interengaged with one another. The crests of the threads of the degassification screws pass in close proximity to the inner surface of the housing headpiece and the extruder screw. The length and cross sectional profile of the degassification screws are such that upon rotation of the screws, the overlapped bores in the housing headpiece are longitudinally and transversely traversed by the screws substantially in entirety.