Process and apparatus for injection molding
CA 2000663 A1 · Owner: Sanri Kabushiki Kaisha · Inventors: Tsutsumi, Shigeru; Tsutsumi, Shigeru
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A system of injection molding by an injection machine with a mold comprises conventional fundamental steps including a material plasticising and metering step, a material injecting step and a material pressure-holding step, but with a additional feature in that a nozzle passage is interrupted midway therealong from communication between the interior of a machine body and a mold cavity, after the injecting step but while the material pressure-holding step is being carried out. The material pressure-holding step is carried out first using the injection machine per se operated with a plunger to exert a first non-stepped external or internal pressure on the entire injected material but second …
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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
- Filed October 13, 1989. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 13, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 13, 2011.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.