Liquid dispensing apparatus and method
CA 2248386 C · Owner: Roberts, Benjamin R. · Inventors: Pozniak, Peter M.; Roberts, Benjamin R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A liquid dispensing method and apparatus in which liquid is dispensed from chambers, that can be pressure vessels to a flow circuit. A valve network is designed such that when one chamber functions in a dispense mode of operation another chamber functions in a return mode of operation in which unused liquid is sent back to such chamber so that liquid is continually circulated. The chamber or vessel undergoing the return mode of operation is vented through a valve that is either a pressure regulation valve having a set point of pressure or a remotely activated control valve response to liquid pressure at the point of use. In such manner internal pressure within the chamber or pressure vessel …
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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 September 25, 1998 and granted February 25, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 25, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 25, 2020.
- 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.