Active harrow
CA 2014441 C · Owner: Highline Mfg. Inc. · Inventors: Bussiere, Ray
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An active harrow comprises a rotatable cylindrical body on the outer surface of which is mounted a plurality of tines which project outwardly for engaging the ground. The rotatable body is carried in a yoke and supported from a tool bar in a manner which allows the axis of the rotatable body to be adjusted relative to the tool bar. The tines are inclined so that they lie in axial planes but inclined relative to the radial plane of an angle in order of 20° to 30°. Each tine includes a main body portion and an end portion which is cranked. This orientation of the tines provides an effective harrowing action but prevents accumulation of trash.
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 April 11, 1990 and granted September 1, 1992. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 11, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 11, 2012.
- 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.