Trenching apparatus
CA 2045656 C · Owner: Camilleri, Paul Anthony · Inventors: Camilleri, Paul Anthony
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Propulsion apparatus (10) is disclosed for urging a trenching arm (12) forward against the advancing face of an elongate trench being dug by the trenching arm. The propulsion apparatus (10) includes a propulsion member (22) which is engageable with the base wall of the trench such that the trenching arm (12) may be urged forward relative to the engaged propulsion member (22). The propulsion member (22) may then be withdrawn from engagement with the base wall and retracted towards the trenching arm (12) before commencing a further propulsion cycle. The propulsion member (22) is also operable to cooperate with the trenching arm (12) in excavating a starting slot at the beginning of a new …
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 January 29, 1990 and granted April 23, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 29, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 29, 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.