Apparatus and method for braking an electric motor
CA 1294669 C · Owner: Unsworth, Peter Joseph · Inventors: Unsworth, Peter Joseph
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An electric motor is coupled to the power lines by thyristors. The motor is braked by triggering the thyristors at the proper times to produce a electro-magnetic field within the motor which opposes the residual magnetic field of the rotor. The proper time to trigger the thyristors is determined by comparing the polarity of the voltage across the power lines to the back emf voltage from the motor. The thyristors are triggered when these two voltages have opposite polarities. The braking circuit also regulates the duty cycle of the thyristors to control the magnitude of the current applied to brake the motor.
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
- Granted January 21, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 21, 2009.
- 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.