Bimetallilämpöilmaisimien

Bimetallilämpöilmaisimet are devices used to detect changes in temperature. They operate on the principle that different metals expand and contract at different rates when subjected to temperature variations. A bimetallic strip is typically constructed from two distinct metals, such as brass and steel, bonded together along their length.

When the temperature rises, both metals expand, but the metal with a higher coefficient of thermal expansion will expand more than the other. This differential expansion causes the bimetallic strip to bend. Conversely, when the temperature falls, the metals contract, and the strip bends in the opposite direction. The degree of bending is directly proportional to the change in temperature.

This bending action can be harnessed to activate a switch or trigger an alarm. In a simple bimetallic thermal switch, the bending strip might make or break an electrical contact, thereby controlling a circuit. This makes them suitable for applications like thermostats, overcurrent protection in electrical devices, and fire alarms. They are a reliable and relatively inexpensive method for temperature sensing and control, though their accuracy can be influenced by factors like ambient pressure and the strip's own mass.