| 摘要 |
<p>A switch combining magnetic control and thermal control. A movable contact is urged by a magnet into contact with a fixed contact. A bimetallic strip is capable of urging the movable contact out of contact with the fixed contact upon exposure to a thermal overload. For a switch responsive to both burglary and fire detection, a permanent magnet urges the movable and fixed contact into a normally closed position. When the magnet's influence is no longer felt, such as when a burglary occurs, the movable and fixed contacts will separate. A bimetallic strip, when sensing a thermal overload, will also move the movable contact out of contact with the fixed contact even in the absence of a burglary. The switch responsive to both magnetic and thermal energy is also used to protect a relay controlled circuit from thermal overload.</p> |
