High symmetry dc squid system
CA 2089181 C · Owner: Quantum Magnetics, Inc. · Inventors: Simmonds, Michael Bancroft
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A thin film dc SQUID and its driving electronic circuitry configured with very high symmetry. The SQUID loop is formed with four holes (24, 25, 26, 27) at the respective ends of crossed slits (22 23). Each of these holes forms a single turn secondary (24, 25, 26, 27) for symmetrically arranged pairs of modulation coils and signal coils. The geometrical placement of the modulation coil transformers with respect to the signal coil transformers results in a device which nominally has no mutual inductance between the two groups of coils when the SQUID is biased for normal operation. The external driving circuit (75-85) is configured to preserve the highly balanced nature of the chip and forces …
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 June 14, 1991 and granted September 16, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 14, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 14, 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.