Air filter gauge
CA 1075540 A · Owner: Nelson, Joseph N. · Inventors: Nelson, Richard D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A gauge detecting the presence of a restriction placed upon an air stream passing through a filter in connection with an internal combustion engine said gauge, including a linear indicator to show the relative restriction present in the filter and including an indicator to show that the filter requires cleaning or replacement.
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
- Granted April 15, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 15, 1997.
- 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.