Door or gate obstruction control
CA 1251843 A · Owner: Automatic Roller Doors Australia Pty. Ltd. · Inventors: Seidel, Raymond L.; Viola, Marian
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An obstruction sensing and control arrangement for door or gate opening-closing mechanisms. The arrangement compares the operating rate of change of a predetermined characteristic with a preset rate of change and stops or reverses the motor in the opening/ closing mechanism. The characteristic preferred is motor body temperature which is monitored indirectly. The control arrangement also includes a back up static control threshold to sense a second static operating characteristic of the motor and a second comparator means set at a preset threshold level to stop or reverse the motor. A common motor sensor is used for both the dynamic and static control thresholds. The invention also includes …
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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
- Granted March 28, 1989. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 28, 2006.
- 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.