Abstract: A sensor for a flushing device having an electric solenoid operated flush valve. The sensor includes a control box, a first radiation emitting source mounted in the control box, a radiation detector adapted to detect reflected radiation from the first radiation emitting source mounted in the control box, a lens cover attached to the control box and adapted to permit radiation to pass therethrough and a control circuit contained within the control box responsive to the sensing unit and connected to the solenoid for initiating operation of the flush valve. The control circuit includes a magnetically activated device for bypassing the sensing unit to initiate operation of the flush valve and deactivate the flush valve for a fixed period of time. Also disclosed is a method of operating the sensor.

Abstract: There is provided an automatic cleaner for a male urinal comprising: a sensor such as pyroelectric sensor, etc. for detecting that a human body comes close to the urinal or away therefrom to output a first signal, an one-shot multivibrator circuit of the retriggerable type triggered in response to the outputted first signal to output a second signal for a predetermined time, an infrared ray emitting circuit adapted for emitting infrared rays in the form of pulse for a time period during which the one-shot multivibrator circuit is outputting the second signal, and an infrared ray receiving circuit adapted for detecting that the emitted infrared rays are reflected by the human body to output a third signal in the form of pulse.

Abstract: An alarm device responsive to entering or trespassing comprising:(a) a sensor circuit, including an infrared ray sensor, producing an output having positive and negative peaks based on outputs of said sensor being produced when a target to be sensed passes within the region of vision monitored by said sensor,(b) a level detecting circuit comprising a first detector producing an output when the positive peak of the output fed from said sensor circuit exceeds a predetermined level, and a second detector producing an output when the negative peak of the output fed from said sensor circuit exceeds a predetermined level,(c) a timer circuit comprising a first timer producing an output which continues for a predetermined time interval or above from a time at which the output of said first detector is produced, and a second timer producing an output which continues for a predetermined time or above from a time at which the output of said second detector is produced,(d) an AND circuit comprising a first circuit produc

Abstract: An ultrasonic alarm device has a detector for detecting a reflected ultrasonic wave in a watching area to obtain a Doppler signal due to motion of a person, a Schmitt circuit for converting the detection output into a pulse output and a waveform shaping circuit for shaping the pulse output into a pulse train having a certain pulse width. The output of the waveform shaping circuit is fed in parallel to two band-pass digital filters, one for the Doppler signal and the other for noise signals. Each of the filters comprises two monostable multivibrators connected in parallel and an AND gate having three inputs of which one is connected through an inverter to the output of one monostable multivibrator, a second is connected to the output of the second monostable multivibrator and the third to the input of the monostable multivibrators.