For safety reasons, the flameout protection device for butane gas stoves is very necessary, and relevant national standards also have mandatory regulations. There are three types of flameout protection methods commonly used in the market: thermal, thermoelectric and photoelectric.
Thermal type: also known as bimetal. The bimetal is made of two metals with different expansion coefficients. Under the action of temperature, the metal side with a large expansion coefficient will bend toward the metal side with a small expansion coefficient. When the temperature is lost, the originally expanded metal is expanded. It will slowly return to its original state, so the bimetal is also called the memory alloy. The sensor that uses the bimetal as a safety protection device utilizes the characteristic that the bimetal is expanded and bent under the action of temperature.
The advantage of the bimetal protection device is that the structure is simple and the cost is low. The disadvantage is that the installation is difficult, the installation position of the bimetal and the cooperation of the plug valve and the gas valve have high requirements, and the heat inertia is large, the valve opening and closing time is long, and the service life is short.
Thermoelectric type: This device also utilizes the heat energy generated when the gas is burned. The thermoelectric flameout safety protection device is composed of two parts: a thermocouple and a solenoid valve. The thermocouple is composed of two different alloy materials. Different alloy materials produce different thermoelectric potentials under the action of temperature. Thermocouples are manufactured by using different thermoelectric potentials of different alloy materials under the action of temperature, which utilizes the electrothermal difference of different alloy materials.
The thermoelectric safety protection device has been widely used because of its simple structure, convenient installation and low cost. However, such a protection device uses a thermocouple as a thermal sensor. The disadvantage is that the thermal inertia is large and the reaction speed is slow, which makes the user feel inconvenient to operate, and has a short service life. The installation accuracy of the plug valve and the solenoid valve is relatively high.
Photoelectric: also known as ion sensing. The device utilizes gas to burn ions while burning and has unidirectional conductive properties. This type of safety protection was first applied to gas water heaters, and has been developed from DC induction to AC induction, which has greatly improved reliability. It has only been used for three or four years on stoves.