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Expired Canadian patentCanada

Semi-active damper for vehicles and the like

CA 1297915 C · Owner: Nobles, Charles M. Jr. · Inventors: Nobles, Charles M. Jr.; Miller, Lane R.; Mcguire, Dennis P.

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

The damper assembly has improved valve means that includes at least one annular movable valve member of the voice-coil type. Such valve member is formed at least in part of composite material that increases the strength and stiffness of the member, while reducing its coefficient of thermal expansion and it weight. In a preferred embodiment of the invention, the assembly includes two movable annular valve members which are driven in unison with each other such that when one occupies a flow-permitting position the other occupies a flow-inhibiting position. Check valves utilized in the assembly preferably are of a resilient split-ring type.

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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

  • Granted March 24, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 24, 2009.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledJune 1, 1988
GrantedMarch 24, 1992
Term endedMarch 24, 2009
Patent numberCA 1297915 C
Classification (IPC)F16F9/46 +1 more

Timeline

Timeline From CIPO dates

1989199219951998200120042007Application filedJune 1, 1988Patent grantedMarch 24, 1992Term endedMarch 24, 2009

Sources & verification

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