Screw head formation
CA 2460163 C · Owner: Brooks, Lawrence Antony · Inventors: Brooks, Lawrence Antony
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The screw has two or three non-circular super-imposed recesses. The depth of each recess is less than 1.2 mm and there is a less than 1~ of draw in each recess. The screw head recess is formed using a punch (10) in a cold-heading process. The punch is formed in a profilating CNC machine cutting the , profiles (12, 14, 16) of the punch to a tolerance of better than .plusmn. 0.025 mm.
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 September 10, 2002 and granted June 6, 2017. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 10, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 10, 2024.
- 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.