Color changing hourglass assembly
CA 2177457 C · Owner: Castanis, George · Inventors: Castanis, George
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A color-changing, position-reversible hourglass assembly having two transparent bulbs one above the other and a storage compartment adjacent each bulb, the bulbs and compartments being joined together by a neck. Intercoupling the bulbs and the compartments is a crossover network which passes through the neck to couple each bulb to the compartment adjacent the other bulb. In operation, when one bulb and its adjacent compartment are in an up position and are respectively loaded with sand of different color, then sand of one color appears to trickle from the up bulb into the compartment in the down position while sand of another color appears to trickle from the up compartment into the down …
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 27, 1996 and granted June 15, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 27, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 27, 2018.
- 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.