Block valve with tank chamber
CA 2134425 C · Owner: Masako Kiyohara · Inventors: Nishimura, Ryutaro
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to a block valve with tank chamber capable of discharging promptly and smoothly the residual gas in gas feed pipings in a semiconductor manufacturing apparatus or the like especially in pipings in which block valves are incorporated. The block valve with tank chamber comprises a gas feed passage possessing an inlet and an outlet a branch, passage possessing an outlet branched off from and communicating with the gas feed passage a body having a, tank chamber formed in the midst of the branch passage a, first valve provided in the body for opening and closing the downstream side of the gas feed passage downstream of the connection point with the branch passage …
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 October 26, 1994 and granted March 31, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 26, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 26, 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.