Loudspeaker horn
CA 2015517 C · Owner: Yoshioka, Tsutomu · Inventors: Yoshioka, Tsutomu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A speaker horn including a first and a second pair of side walls. The first pair of side walls has a first section and a second section between first and second ends and the, second pair of side walls has a third section and a fourth section between third and fourth ends. The first pair of side walls has, in a first plane including the central axis of the horn and perpendicular to the side walls of the first pair, a shape defined by the following equation: y = a + b.ecx, where a, b and c are constants and have values different in said first and said second sections, and the second pair of side walls is, in a second plane including the central axis of the horn and perpendicular to the side …
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 April 26, 1990 and granted December 13, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 26, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 26, 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.