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Retro-reflective infrared safety sensor for garage door operators

  • US 5,656,900 A
  • Filed: 06/05/1995
  • Issued: 08/12/1997
  • Est. Priority Date: 06/05/1995
  • Status: Expired due to Fees
First Claim
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1. A garage door operator comprising:

  • an electric motor;

    a transmission connectable to the electric motor for connection to a garage door to open and close the garage door;

    a control unit connected to the electric motor to command the electric motor to open and close the garage door;

    a synchronizing signal generator for generating a synchronizing signal;

    an infrared emitter enabled by the synchronizing signal for directing toward a reflector a pulsed infrared beam;

    an infrared detector positioned in proximity with the infrared emitter for generating a pulsed beam detection output signal in response to the reflected infrared pulses; and

    a missing pulse detector enabled by the synchronizing signal and coupled to receive the pulsed beam detection output signal from the infrared detector, for supplying a missing pulse signal to said control unit when the pulsed beam detection output signal is absent.

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