Self-tightening electrical sleeve heater
CA 2242367 A1 · Owner: Schwarzkopf, Eugen · Inventors: Schwarzkopf, Eugen
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An electrical sleeve heater has a tubular outer wall and a heating coil inside the outer wall. An outer sleeve inside the heating coil formed with an axially throughgoing slot having angularly confronting edges is made of a material having a high coefficient of thermal expansion. An inner sleeve inside the outer sleeve is formed with an axially throughgoing slot and with outwardly projecting lips engaged through the outer-sleeve slot bearing angularly on the outer-sleeve slot edges. It is made of a material having a low coefficient of thermal expansion so that when the sleeves are heated the outer-sleeve edges press the inner-sleeve lips together and thereby decrease the radial inner …
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
- Filed July 6, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 6, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 6, 2020.
- 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.