Valves
CA 1081583 A · Owner: Hnl Instruments & Controls Limited · Inventors: Hayward, Terence J.; Berrecloth, Alan H. T.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A fluid control valve, especially intended as a pilot valve in pneumatic control systems, in which the controlled flow path is provided by the gaps between adjacent coils of a helical spring. The flow direction is from the outside to the inside of the spring; this allows the valve to seal against high pressures, since the spring will be helped to remain closed by the pressure forces acting thereon.
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 July 15, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 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.