Ventilator fan switch for cooker hood - evaluates signal from infrared receiver detecting radiation from transmitter reflected to it from steam collecting under hood

摘要

A switching circuit operates according to the steam drawn in by the hood. An infrared transmitter (6) and receiver (7) are arranged below the cooker hood fan. The transmitter and receiver are inclined w.r.t. the line between them and towards a zone (9) below the fan. An evaluation circuit fed by the receiver signal switches on the fan when infrared radiation is reflected to it by steam in this zone. The radiation cone of the receiver is directed close to the cooker. A stop is arranged between the transmitter and receiver. USE - To detect and evaluate steam produced during cooking for cooker hood fan control.