Differential pressure control apparatus
CA 1234612 A · Owner: Johnson Service Company · Inventors: Spence, Scott L.; Hayes, Thomas E.; Jamieson, Jerel S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A differential pressure control apparatus includes a switch responsive to a pneumatic differential pressure for signaling the actuation of a blower motor. A signal generating section is provided and controls the speed of a blower for regulating the differential pressure. This section includes first means for sensing a projected light beam and second means for modulating the light beam. The first means and the second means are positionably displaceable one to the other in response to the magnitude of the differential pressure. Two preferred embodiments are disclosed.
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 March 29, 1988. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 29, 2005.
- 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.