Patent Yard Sign in
Expired Canadian patentCanada

Box-spring core

CA 2089485 C · Owner: Stumpf, Walter · Inventors: Gerking, Helmut; Stumpf, Walter

CIPO record

Overview

Drawings and full text

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

Open the CIPO record

Abstract From the Canadian patent

A box-spring core has a first group of first chains extending spacedly adjacent and parallel to one another and a second group of second chains extending adjacent and parallel to one another and transversely of the first chains. Each of the chains has an elongated flexible sheath formed with a plurality of longitudinally spaced transversely extending, and through-going slits that are each transversely aligned with the slits of adjacent sheaths, a transverse seam adjacent each slit and internally subdividing the respective sheath into a respective succession of longitudinally spaced pockets and respective, springs in the respective pockets each compressible in a transverse direction parallel …

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 August 20, 1991 and granted December 30, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 20, 2011.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 20, 2013.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledAugust 20, 1991
GrantedDecember 30, 2003
Term endedAugust 20, 2011
Patent numberCA 2089485 C
Classification (IPC)A47C27/06 +1 more

Timeline

Timeline From CIPO dates

1992199419961998200020022004200620082010Application filedAug 20, 1991Patent grantedDec 30, 2003Term endedAug 20, 2011

Sources & verification

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