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:
Mar. 16, 1982
Filed:
Apr. 21, 1980
Gerd P Lupke, Thornhill, Ontario, CA;
Manfred A Lupke, Thornhill, Ontario, CA;
Other;
Abstract
Apparatus for producing corrugated thermoplastic tubing of the type comprising a pair of complementary upper and lower mold assemblies each having an endless chain of articulately interconnected mold blocks which are driven along a forward run and back along a return run, the mold blocks cooperating in pairs along the forward run to form an axially extending tubular mold tunnel, within which the tubing is expanded by vacuum forming or blow molding. The mold blocks have mold-defining faces of corrugated form with alternating troughs and crests. Each mold block is formed with passages which extend between the bases of the troughs of the corrugations and the exterior of the mold block. These passages communicate with the base of each trough throughout its length, and serve to permit the escape of any atmospheric air which is trapped by the tubing in the troughs during expansion of the tubing.