Leadscrew-type elevator with safety covers useful in stairways
CA 2020604 C · Owner: Heck, Jorg · Inventors: Heck, Jorg
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 lifting device (1) for moving loads (6), even up and down stairways (21) with a frame (2), that incorporates a set of wheels (4) and a driven shaft (3) that extends in the longitudinal direction within the frame and a slide (5) to accommodate the load, said slide being supported so as to slide on the frame (2) and which is also connected through a supporting structure (17) to a nut (18) that runs on the threaded shaft (3). In order to cover the threaded shaft (3) with a shaft covering (28) on the side that is proximate to the slide (5), the supporting structure (17) is so configured between the nut (18) and the slide (5) that it encloses this shaft …
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 July 6, 1990 and granted May 28, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 6, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 6, 2012.
- 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.