Combined dust and gas sensor for protective safety system in plastics processing, baking and milling

摘要

A combined dust and gas sensor has a heated gas sensor (1) facing an electrode (2) at an interval of between 1 and 10 mm. A voltage U is applied across the electrode (2) and sensor (1) which generates an electric field (E). The electrode is represented by the tips of one or more naked wires and acts as a Davy safety grid. The power supply is a blocking oscillator with a high voltage cascade. The sensor (1) operates at high temperature and is based on a semi-conducting metal oxide. The voltage applied is 5000 Vat a distance of less than 50 mm.