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Expired Canadian patentCanada

Stamp formed muffler with hermetically sealed laminated outer shell and method of manufacture

CA 2118780 C · Owner: Ap Parts Manufacturing Company · Inventors: Harwood, Jon W.

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

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Abstract From the Canadian patent

A muffler and a method of manufacturing a muffler are provided. The muffler includes a pair of stamp formed laminated external shells, each of which includes inner and outer layers. The inner and outer layers are stamped simultaneously to nest with one another. However, the respective layers of each laminated shell will spring back slightly differently from one another in view of different metallurgical characteristics inherent in each sheet. The laminated external shells are then disposed around internal components of the muffler, and peripheral regions are securely clamped together. This clamping in view of the, differential spring-back creates a narrow air chamber between the layers of …

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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 March 10, 1994 and granted August 18, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 10, 2014.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 10, 2016.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledMarch 10, 1994
GrantedAugust 18, 1998
Term endedMarch 10, 2014
Patent numberCA 2118780 C
Classification (IPC)F01N13/00 +2 more

Timeline

Timeline From CIPO dates

1995199719992001200320052007200920112013Application filedMarch 10, 1994Patent grantedAug 18, 1998Term endedMarch 10, 2014

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.