Peak flow meter
CA 2135965 C · Owner: Shene, William R. · Inventors: Shene, William R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A peak flow meter is provided comprising an elongated body having a longitudinal direction and a predetermined cross sectional shape and a growing area. The body has an open entering end and an open exit end. The body is circumferencially continuous substantially from end to end. A piston and an indicator are mounted in said body for movement longitudinally thereof upon exhalation into the open entering end. The indicator is pushed along said body for movement by the piston longitudinally of said body. The indicator is of low mass so as not to overshoot and is, returned to rest by shaking a weight against it. A logarithmic scale is provided along said body against which the position of said …
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 November 16, 1994 and granted September 5, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 16, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 16, 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
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.