The invention is directed to improved automatic dispenser apparatus for dispensing
sheet material and the like without contact between a user and the dispenser. Proximity
detection apparatus is provided to detect the presence of a user in a detection
zone generated outside the dispenser. Control apparatus controls actuation of the
dispenser in response to the detected user. Preferred forms of the proximity detector
include a sensor and a signal detection circuit operatively connected to the sensor.
The sensor includes conductors configured to have a capacitance and positioned
such that the capacitance is changed by the presence of a user within the detection
zone. The signal detection circuit detects the change in capacitance and is provided
with an oscillator having a frequency which is affected by the sensor capacitance
and a differential frequency discriminator which detects changes in the oscillator
frequency. The control circuit receives the detected frequency change and generates
a signal provided to actuate the dispenser to dispense the material.