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Expired Canadian patentCanada

Down pressure system with free float extension

CA 2199050 C · Owner: Wodrich, Timothy Dirk · Inventors: Wodrich, Timothy Dirk; Stanfill, Ralph Everette

CIPO record

Overview

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Its claims, description and drawings are in the Canadian Patents Database.

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Abstract From the Canadian patent

An opener for use in varying ground conditions ranging from no-till to conventional, full tillage conditions includes an adjustable down pressure control and a down pressure spring and tension link assembly which selectively provide a limited free float opener condition or a conventional down pressure spring controlled bias condition. A sleeve slidably received by the opener arm and mounted over the lower portion of the tension link assembly allows the opener to free float in loose soil conditions so that only the weight of the opener provides downward bias when the down pressure control is adjusted to a minimum condition. The opener is free to ride up and down to follow irregularities in …

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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 March 3, 1997 and granted February 20, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 3, 2017.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 3, 2019.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledMarch 3, 1997
GrantedFebruary 20, 2001
Term endedMarch 3, 2017
Patent numberCA 2199050 C
Classification (IPC)A01B5/06 +2 more

Timeline

Timeline From CIPO dates

1998200020022004200620082010201220142016Application filedMarch 3, 1997Patent grantedFeb 20, 2001Term endedMarch 3, 2017

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.