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. 28, 1981
Filed:
Oct. 01, 1979
Thomas G Bishop, Mount Gilead, OH (US);
HPM Corporation, Mount Gilead, OH (US);
Abstract
An injection molding machine which is capable of injecting both thermoplastic compounds and glass loaded thermosetting polyester compounds, wherein the machine is capable of rapid conversion from its thermoplastic configuration to its thermosetting configuration, and vice versa. The machine comprises an elongated charge forming barrel having a rearward thermoplastic feed opening, which is customarily supplied by pelletized thermoplastic material from a vertical feed hopper, and a thermosetting material feed opening extending into the barrel at a position forwardly of the thermoplastics feed opening. When processing thermoplastics materials, a conventional, fully flighted plasticizing screw is installed in the barrel so that the pelletized material is conveyed forwardly from the rear feed opening, and plasticized for subsequent injection. During thermoplastics processing, the thermosetting feed opening is plugged. To convert the machine to process the aforementioned thermosetting materials, the second feed opening is unplugged, and the plasticizing screw is exchanged for a deeper flighted conveying screw having flights extending from the forward end thereof to just behind the unplugged, second opening. A stuffer unit is then attached to the unplugged feed opening and dough-like glass loaded thermosetting material is forced through the second opening into the barrel by means of a reciprocating plunger, or the like. The thermosetting material is conveyed forwardly and mixed slightly as the screw rotates.