Patent Yard Sign in
Expired Canadian patentCanada

Method and mold for sand casting varying thickness articles

CA 1264918 C · Owner: Witt, Raymond H. · Inventors: Witt, Raymond H.

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 permanent casting mold has its casting cavity coated with a sand liner of varying thickness. The liner is thicker where the cast article section is thinner and the liner is thinner where the cast article section is thicker so as to permit the thicker sections to cool faster while the thinner sections cool slower. The different thicknesses of the liner are correlated so that the respective sections of the article are sufficiently cooled at about the same time for removal of the article from the mold. The mold is a cope and drag-type flask mold whose casting cavity halves are oversized relative to the cast article. The said liner is formed therein by temporarily positioning a pattern within …

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 January 30, 1990. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 30, 2007.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledApril 21, 1987
GrantedJanuary 30, 1990
Term endedJanuary 30, 2007
Patent numberCA 1264918 C
Classification (IPC)B22C9/02 +2 more

Timeline

Timeline From CIPO dates

1988199019921994199619982000200220042006Application filedApril 21, 1987Patent grantedJan 30, 1990Term endedJan 30, 2007

Sources & verification

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