Oil return from evaporator to compressor in a refrigeration system
CA 2274890 C · Owner: American Standard Inc. · Inventors: Carey, Michael D.; Smith, Sean A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A refrigeration system (10) employing a screw compressor (12) and a falling film evaporator (20) makes use of high-side pressure to drive lubricant, which escapes the compressor (12) and collects as a lubricant-rich mixture of lubricant and refrigerant in the system evaporator (20), back to the compressor (12). The mixture is cyclically exposed to high-side pressure for a period of time which (i) varies in accordance with the difference between a sensed condenser-related pressure and a sensed evaporator-related pressure and (ii) is calculated to maintain a predetermined oil concentration in the lubricant-rich mixture in the evaporator (20) so as to minimize the oil return process.
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 January 28, 1998 and granted March 26, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 28, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 28, 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.