Mixed mode stepper motor controller and method
CA 2094748 C · Owner: Eyerly, Bruce N. · Inventors: Eyerly, Bruce N.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A mixed mode controller (100) for use with a motor having a mechanism (110, 114) for generating a command signal to operate the motor and a first circuit (104) for adjusting the gain of the command signal to provide high speed operation. A second circuit (102) is provided for converting the command signal to a drive signal to excite a winding (106) and to damp the motor. In a preferred embodiment, a step rate signal introduced into the motor controller (100) is operated upon by an accumulator (110) and a memory (114) to generate a voltage command signal. The motor controller (100) includes a low bandwidth current control feedback loop (104) utilized to adjust the gain of the voltage command …
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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 April 23, 1993 and granted November 25, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 23, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 23, 2015.
- 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
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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.