Sheet metal screw
CA 1184053 A · Owner: Illinois Tool Works Inc. · Inventors: Barth, Gerald D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A sheet metal screw providing increased strip torque. A helical ramp is formed as an extension to the thread and is partially surrounded by a recess in the lower surface of the head. The material of the tapping panel is drawing upwardly through the clearance hole in the bearing panel into engagement with the helical ramp. The farther up the surface of the ramp the material of the tapping panel is drawn, the greater the magnitude of the stripping torque.
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 March 19, 1985. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 19, 2002.
- 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.