Optical smoke detector
CA 1081821 A · Owner: Nittan Company, Limited · Inventors: Tagashira, Hiroshi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Of Disclosure, An optical smoke detector which includes a light source and light sensing element so arranged that the quantity of light detected by the element will be determined by the presence of smoke in the detector, a power source for periodically supplying sets of actuating pulses to the light source, apparatus connected with the light sensing element for detecting light pulses which are synchronized with the actuating pulses and producing an alarm when pulses of a predetermined magnitude are detected.
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 July 15, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 15, 1997.
- 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.