Patent Yard Sign in
Expired Canadian patentCanada

Vented injection molding machine

CA 1097471 A · Owner: Hpm Corporation · Inventors: Gudermuth, Clyde S. Jr.; Kruder, George A.

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

Open the CIPO record

Abstract From the Canadian patent

A vented injection molding machine adapted to handle a wide variety of synthetic resinous materials without pre-drying is disclosed. The molding machine includes a two-stage screw rotatably and reciprocably mounted within a barrel. The barrel includes a pair of ends, a feed opening at one end and a vent opening intermediate the pair of ends. A first stage of the screw essentially completes material plastication. The first stage has a protruding helical screw flight with a first pitch and includes a feed section communicating with the feed opening, a transition section, and a pumping section. A second stage of the screw includes a deep flighted vent section which communicates with the vent …

Read the whole patent

Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Granted March 17, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 17, 1998.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledOctober 20, 1977
GrantedMarch 17, 1981
Term endedMarch 17, 1998
Patent numberCA 1097471 A
Classification (IPC)B29C48/76 +2 more

Timeline

Timeline From CIPO dates

1978198119841987199019931996Application filedOct 20, 1977Patent grantedMarch 17, 1981Term endedMarch 17, 1998

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.