Slotted diaphragm loudspeaker
CA 2283281 C · Owner: House, William Neal · Inventors: House, William Neal
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A loudspeaker (10) comprises a diaphragm having an outer perimeter (24) a , voice coil (18), a frame for supporting the diaphragm and a motor stator (26) , providing a magnetic field in which the voice coil is supported. Ribs (43) extend outwardly at the perimeter (24) of the diaphragm to mount the voice coil to the perimeter of the diaphragm. The motor stator (26) includes at least one inner flux return (32) providing slots (46) through which the ribs (43) extend between the perimeter of the diaphragm and the voice coil (18).
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 7, 1998 and granted November 28, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 7, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 7, 2020.
- 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.