Synchronous rectification type controller for direct current motors and method of making
CA 2133469 C · Owner: Hellinga, Richard J. · Inventors: Lankin, Andrew E.; Lankin, Robert; Hellinga, Richard J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A MOSFET (50, 51) control topology and a physical structure for a motor control which provide a more efficient and economic DC motor control are disclosed. The control topology introduces a synchronous-rectification technique wherein free-wheel diodes are replaced with MOSFET (50, 51) devices that are switched on and off by a logic circuit (38) so that they are conductive for commuting motor current during periods that the motor (24) current supply is switched off. The physical structure and method of assembling a DC motor control (33) eliminate time consuming assembly techniques while ensuring effective waste heat exchange between electronic components (46, 50, 51) and a heat sink (96) of …
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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 March 30, 1993 and granted September 30, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 30, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 30, 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
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.