The Bimetallic strip is a mechanical temperature sensor element. It converts temperature to a mechanical displacement. This displacement may be coupled to a switch for simple on-off function, to a needle of an indicator, or to a position detector for electronic output.
A bimetallic strip, also called bimetal strip could consist of a strip of brass and a strip of steel welded together. When the strip is heated, brass expands more than iron. This expansion will make the strip bend toward the iron.
Bimetallic strip thermometers are mechanical thermometers. They are widely used in industry for temperature control because of their robustness, temperature range and simplicity. It consists of two strips made of dissimilar metals and bonded together with one end fixed and the other free.
Bimetal strips — also known as bimetallic strips — are used in electronics and thermal engineering as a means of transferring thermal energy into mechanical movement. A common application of this technology is in thermostats or heat sensitive switches in which a circuit is either connected or broken when a certain temperature is reached. The strips work by pairing two metals which react to changes in temperature at different rates, causing the two strips to bend in a certain direction in an effect similar to the refraction of a light beam entering a glass block. Decide on the purpose of your bimetallic strip.
Bulb thermometers are good for measuring temperature accurately, but they are harder to use when the goal is to control the temperature. The bimetallic strip thermometer, because it is made of metal, is good at controlling things. The principle behind a bimetallic strip thermometer relies on the fact that different metals expand at different rates as they warm up.
A fair amount of calls also come through from customer service with customers claiming that the parts are defective. The crucial component of our thermal switches is a bimetal strip. As the two metals have different coefficients of expansion any changes in temperature will cause the bimetal strip bend one way or the other depending on an increase or decrease in temp.
Bimetal Disc Thermostats They do not teach bimetal thermostats in electrical engineering. However, they are found in most appliances as the device that regulates temperature or as a safety device. They are in heaters, toasters, cooktops, ovens, dryers clothes irons, refrigerators, freezers, compressors and motors.
Temperature conveys the state of a mechanical systemin terms of expansion or contraction of solids, liquids or gases, change in electrical resistance of conductors, semiconductors and thermoelectric emfs. Temperature sensors such as bimetallic strips, thermocouples, thermistors are widely used in monitoring of manufacturing processes such as casting, molding, metal cutting etc. The construction details and principle of working of some of the temperature sensors are discussed in following sections.
A bimetallic strip is used to convert a temperature change into mechanical displacement. The strip consists of two strips of different metals which expand at different rates as they are heated, usually steel and copperor in some cases steel and brass. The strips are joined together throughout their length by rivetingbrazing or welding.