Water-activated survival lamp unit and an improved water sensing switch therefor
CA 2029235 C · Owner: Errington John Enterprises Inc. · Inventors: Brain, John Errington
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A water-activated survival lamp unit for mounting to a flotation device in proximity to the water line. The survival lamp unit comprises a hermetically sealed light transmissive housing in which are mounted a light source and a battery in an electrical circuit together. A watersensitive actuator is provided, including a pair of electric terminals extending outside the housing in a spaced apart relationship. The actuator is responsive to a momentary electrical path established between the terminals through a coherent body of water to close the electrical circuit between the battery and the light source for a predetermined time period largely exceeding the duration of the electrical path, …
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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 November 2, 1990 and granted January 22, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 2, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 2, 2012.
- 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.