Annular hole cutter
CA 1206781 A · Owner: Hougen, Everett D. · Inventors: Hougen, Everett D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the Disclosure An annular hole cutter wherein each tooth is formed with a radially outer cutting edge and at least alternate teeth are formed with radially extending cir-, cumferentially staggered inner and outer cutting edges. The bottom face of each tooth is formed with oppositely radially inclined inner and outer back-off faces which intersect in a downwardly extending crest which in turn intersects the radially outer cutting edge. The outer back-off faces of alternate teeth are vertically relieved relative to the outer back-off faces of the intermediate teeth and the inner back-off faces of the intermediate teeth are vertically relieved relative to the inner back-off faces …
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 2, 1986. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 2, 2003.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.