How to use the double metal thermometer control the temperature of the refrigerator?

Refrigerator, it is now essential in daily family an appliance, it can adjust the temperature, and food match the required temperature, in order to achieve the effect of food preservation. To adjust the action of temperature and itself, mainly rely on the built-in bimetallic thermometer. So how do you use the double metal thermometer automatically control the temperature of the refrigerator? Refrigerator, when the temperature reaches a certain critical point, through the switch to start the compressor refrigeration; When the temperature returns to the critical point, a switch to stop the compressor. So temperature can control near the critical point. The bimetallic thermometer is this switch, such as 0 degrees, metal length 37. When 5 px to 15 degrees to 45 px, take advantage of the elongation of the 7. 5 px to control. And, its structure by corrugated pipe, thermal bag ( Test tube) , eccentric, micro switch, etc. , to form a sealed induction system and a transmit signal power steam pressure type. Bellows action in the spring, spring tension is controlled by a knob on the panel, the capillary in the refrigerator freezer, react to the indoor cycling return air temperature. When the temperature rising to the setting temperature, thermal dose of gas expansion of capillary and bellows, bellows elongation and overcome the spring tension connected the switch contact, the compressor operation, refrigeration system, until again fell to the set temperature, the heat pack gas contraction, corrugated pipe shrinkage action with spring, puts switch off position, make the compressor motor circuit is cut off. This action repeatedly, so as to achieve the goal of controlling temperature. Through the above simple introduction, I think we understand the bimetallic thermometer is how to realize the automatic control the temperature of the refrigerator.