4-cycle engine
CA 2071458 C · Owner: Kawahara, Yoshitaka · Inventors: Nakachi, Masaaki; Nakatani, Yoshihide; Kawahara, Yoshitaka
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The known 4-cycle internal combustion engine including a crankcase, a cylinder, a cylinder head a, piston adapted to reciprocate within the cylinder a combustion chamber formed by the piston the cylinder and, the cylinder head, and a crankshaft connected to the piston via a connecting rod, is improved in order to enhance a thermal efficiency, to lower an exhaust level of fuel and to make it possible to arbitrarily select-an operation attitude of a 4-cycle engine. The improved 4-cycle engine comprises an intake passage and an exhaust passage provided in the cylinder head, a rotary valve rotating synchronously with the crankshaft at a speed one-half of that of the latter for communicating the …
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 June 17, 1992 and granted March 25, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 17, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 17, 2014.
- 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.