Hand operated chain block
CA 2236621 C · Owner: Uesugi, Takasi · Inventors: Kobayasi, Eikiti; Uesugi, Takasi; Okamoto, Yosiaki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
To provide a hand operated chain block which can be downsized while enabling a hand chain to be easily wound over a hand wheel without disassembling the hand wheel from a chain block body when the hand chain is seated in the hand wheel a hooking groove for the hand chain to be hooked is formed in an outer plate of the hand wheel having an inner plate and the outer plate between which the hand chain is fitted. For winding the hand chain over the hand wheel it is only necessary that after the hand chain is hooked by the hooking groove the hand wheel is turned.
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 May 5, 1998 and granted July 10, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 5, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 5, 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.