Spark plug for internal combustion engine
CA 2013129 C · Owner: Harada, Akihisa · Inventors: Moriya, Toru; Harada, Akihisa; Goto, Eigo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A spark plug for an internal combustion engine is disclosed. A semiconductor material having a resistance of 5 x 10 2 - 5 x 10 4 Mn/mm is coated or baked in the form of a band on the peripheral surface of a basal part of a leg portion of an insulator of the spark plug. Preferably, at least the basal part of the leg portion, including the band, is covered with a water-repellant insulating coating. An inner wall of a metal shell of the spark plug is desirably coated with a water-repellant material at an area facing at least the peripheral surface of the basal part of the leg portion of the insulator. The band of the semi-conductor material is effective for preventing the orientation of carbon …
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 March 27, 1990 and granted February 17, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 27, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 27, 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.