Vacuum control system for lifting systems
CA 2038775 A1 · Owner: Unitech Industries, Inc. · Inventors: Messinger, Robert
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention provides improved body length adjustment means for a vacuum powered lifting system of the type that embodies a variable length lifting body responsive to the differential of pressure inside that body with atmospheric pressure to resolve critical manual control problems. Thus control is provided by proportional movement of a control member over a substantially linear range producing a smooth progressive movement of the lifting mechanism. This permits non-critical lowering and release of a work load object by unskilled operators. Thus, an air injection valve with an air release port is positioned within the lifting body having an elongated slot operable over a control range …
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 March 27, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 27, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 27, 2013.
- 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.