摘要 |
A safety device for detecting a flow of fumes inside an exhaust pipe of a gas apparatus for producing sanitary hot water and/or for room heating, comprising a main body (2,5) which, in use, is fixed inside a fumes exhaust pipe. On the main body a mobile element (10) can oscillate, with respect to the main body, about an axis (9) basically perpendicular to the outflow of the fumes passing through the exhaust pipe. A position transducer (8, 13) detects at least two positions of the mobile element in relation to the main body, corresponding with a flow of fumes respectively higher or lower than a threshold value, and generates a signal which indicates said two positions. The transducer is preferably comprised of a Hall-effect sensor (8) mounted on the main body (5) and of a magnetic element (13) mounted on the mobile element (10). |