Temperature monitor with excess temp. electrical switch

摘要

The temperature sensitive switch has a cylindrical housing (10) with a cup shaped base (11) and a cover (22) that is sealed in position by a rolled over lip (14). Within the enclosed housing is a bimetallic switch (15) that has a spring disc (16) with a movable contact (17) and is coupled to the bimetallic snap action disc (18). Under normal conditions the movable contact element is held against a fixed contact rivet (21) in the cover. The underside of the non conducting cover has a PTC thermistor (24), produced in a sputtering process, with ring formed contact tracks (25,26). The temperature dependent characteristic of the resistance results in the bimetallic switch latching at a threshold value.