Electrical device, especially hand dryer with sensor, has evaluation electronics generating switch-on signal for fixed period if receiver receives certain number of pulses in two packets

摘要

The device has a sensor in the form of a transmitter, a receiver of reflected radiation and evaluation electronics for switching the hand dyer. The transmitter sends a series of pulse packets, each containing a number of pulses with the interval between packets greater than each packet duration. The evaluation electronics generates a switch-on signal for a fixed period if the receiver receives a certain number of pulses in two packets. The device has a sensor in the form of a transmitter (6), e.g. an infrared or ultrasonic transmitter, a receiver (7) of reflected radiation and evaluation electronics (5) for switching the hand dyer. The transmitter sends a series of pulse packets, each containing a number of pulses with the interval between packets greater than each packet duration. The evaluation electronics generates a switch-on signal for a fixed period if the receiver receives a certain number of pulses in two packets and maintains it if a further signal is received within the period.