Method of inspecting abnormality occurring inside pipe and apparatus for practicing the method
CA 2121311 C · Owner: Kobori, Takashi · Inventors: Furusawa, Hajime; Suyama, Kiichi; Kobori, Takashi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of inspecting an abnormality occurring inside a pipe to be inspected and an apparatus for practicing the method, includes the steps of transmitting an electric wave having a predetermined frequency from an antenna of a transmitter located at a predetermined position inside the pipe, receiving the transmitted electric wave by an antenna of a receiver located at a predetermined position inside the pipe and discriminating, the characteristic of the received electric wave. The characteristic of the received electric wave is the intensity of the electric wave, and an attenuation amount is detected in the first example. On the other hand the, characteristic of the received electric wave …
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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 14, 1994 and granted June 25, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 14, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 14, 2016.
- 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
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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.