Expired Canadian patentCanada
Railway crossing signal
CA 311237 A · Owner: Jakob Trumm · Inventors: Jakob Trumm
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordRead 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 May 12, 1931. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 12, 1948.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Filed—
GrantedMay 12, 1931
Term endedMay 12, 1948
Patent numberCA 311237 A
Classification (IPC)B61L5/12 +1 more
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.