Harrow
CA 1047823 A · Owner: Beattie, Wilfred A. S. · Inventors: Beattie, Wilfred A. S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A rectangular frame carries a plurality of transverse tooth bars pivoted to the frame with each bar carrying a plurality of harrow teeth. A lever arm extends upwardly from each tooth bar and is connected by a spring to the frame so that an obstruction engaged by any one of the teeth will move the tooth rearwardly against the pressure of the spring which will return the tooth to the original position when the obstruction is passed. A block is bolted to the frame adjacent each lever and may be rotated to any one of four positions and is engaged by the lever and may be rotated to any one of four positions and is engaged by the lever to control the angle of the lever with the horizontal and …
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 February 6, 1979. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 6, 1996.
- 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.