Patent Yard Sign in
Expired Canadian patentCanada

Prestressed structural support and method for making same

CA 1285737 C · Owner: Trus Joist Macmillan A Limited Partnership · Inventors: O'Sullivan, Kevin B.; Troutner, Arthur L.

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

The invention comprises an improved structural support member, and method for making the same having, bonded wood beam members which are prestressed during the bonding process. The prestressing is such that significant stresses are induced in an outer surface in at least one of the beam members and at least partially retained by the cured bond. The stresses are such that a significant compression prestress is induced at the bottom surface of the structural support whereby it is capable of carrying a much greater load represented by the compression prestress at the bottom surface.

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

  • Granted July 9, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 9, 2008.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledMay 25, 1987
GrantedJuly 9, 1991
Term endedJuly 9, 2008
Patent numberCA 1285737 C
Classification (IPC)E04B5/12 +1 more

Timeline

Timeline From CIPO dates

1988199119941997200020032006Application filedMay 25, 1987Patent grantedJuly 9, 1991Term endedJuly 9, 2008

Sources & verification

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