Screw head with slant rib and punch for making such screw heads
CA 2113085 C · Owner: Phillips Screw Company · Inventors: Grady, John H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A screw head is provided with ribs (26) on some of the driver engageable surfaces. The rib (26) is slanted outwardly from the screw axis by a small angle A between 1° and 10°. A punch (150) for making a screw head with ribs (26) on some of the driver surfaces includes a slanted groove (168) for providing a rib (26) which is slanted from the screw axis by a small angle A between 1° and 10°.
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 May 28, 1992 and granted July 1, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 28, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 28, 2014.
- 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.