Electric iron（6）

The circuit of a thermostat electric iron is composed of heating elements, thermostats, indicator lights, power terminals and power plugs. After inserting the power plug into the mains socket, the 220V power supply is added to the two ends of the heating element through the power plug, the power terminal and the temperature controller, so the power is turned on to heat, and the iron soleplate is heated; at the same time, it is connected to the heating element through the current limiting resistor. The neon bulbs on both ends of the lamp are also energized, indicating that the electric iron is working. After the soleplate is heated to a certain temperature, the fabric can be ironed. When the temperature reaches the temperature set by the thermostat, the power is turned off and the power is cut off to stop heating and the light goes out; afterwards, the bottom plate gradually cools down. When the temperature drops to the operating temperature, the contact automatically turns on, and turns on again. The power supply is repeated so as to achieve the purpose of automatic temperature adjustment.

The working principle of an electric iron: The temperature of the tool that converts electrical energy into heat is determined by its own power and the length of the energization time. The longer the wattage is, the faster the temperature rises, the higher the temperature, and the slower the temperature, the lower the temperature. The heating elements of electric irons include mica skeleton heating elements and metal tube heating elements. The electric iron made of mica skeleton heating element has simple structure, easy manufacture, relatively uniform heating, and convenient maintenance. The disadvantage is that the heating wire is exposed to the air, oxidizes quickly at high temperatures, has a short life span, is easily affected by humid air, and has insulation properties. Poor. Electric irons made of metal tube heating elements have good mechanical strength, long life, high thermal efficiency, good moisture resistance, safety and reliability, but the manufacturing process is more complicated.