Switch device
CA 1234895 A · Owner: Hodges, Robert J. · Inventors: Sheppard, Robert; Greenwood, John C.; Hodges, Robert J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the Disclosure A contactless electrical switch has a switch element comprising a piezo-resistive transducer (25). Coded toothed cams (16) operated via a shaft (14) deflect the transducer (25) causing corresponding changes in stress and hence resistance. The output of the transducer is amplified and fed to logic circuitry which determines a corresponding current path.
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 April 5, 1988. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 5, 2005.
- 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.