Intermediate pipe-jacking apparatus
CA 2015497 C · Owner: Akesaka, Toshio · Inventors: Akesaka, Toshio
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An intermediate pipe-jacking apparatus is adapted to propel pipes such as sewer pipes, conduit pipes and the like in the ground between a start shaft and a destination shaft in order to install the pipes in the ground. More specifically, the intermediate pipejacking apparatus disposed between the pipes to be propelled comprises a movable frame disposed inside the pipes, a plurality of hydraulic jacks supported by the frame, and an operating mechanism for shifting the hydraulic jacks between the operative position between the end faces of the pipes and the inoperative position inside the pipes, wherein the frame is provided with a pair of hollow end frame members, and a plurality of rod …
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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 April 26, 1990 and granted May 24, 1994. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 26, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 26, 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.