1. External heating electric soldering iron
It consists of soldering iron tip, soldering iron core, shell, wooden handle, power lead, plug and other parts. Because the soldering iron head is installed inside the soldering iron core, it is called an external heating type electric soldering iron. The soldering iron core is the key part of the electric soldering iron. It is formed by winding the heating wire in parallel on a hollow porcelain tube. The mica sheet in the middle is insulated, and two wires are drawn out to connect with the 220V AC power supply.
There are many specifications of external heating electric soldering iron, commonly used are 25W, 45W, 75W, 100W, etc. The higher the power, the higher the temperature of the soldering iron tip. The power specification of the soldering iron core is different, and its internal resistance is also different. The resistance of a 25W soldering iron is about 2kΩ, the resistance of a 45W soldering iron is about 1kΩ, the resistance of a 75W soldering iron is about 0.6kΩ, and the resistance of a 100W soldering iron is about 0.5kΩ.
2. Internal heating electric soldering iron
It consists of a handle, connecting rod, spring clip, soldering iron core, and soldering iron tip. Because the soldering iron core is installed inside the soldering iron head, it heats up quickly and has a high heat utilization rate. Therefore, it is called an internal heating type electric soldering iron. The commonly used specifications of internal heating electric soldering iron are 20W and 50W. Due to its high thermal efficiency, a 20W internal heating soldering iron is equivalent to a 40W external heating soldering iron.
3. Constant temperature electric soldering iron
Since the constant temperature electric soldering iron head is equipped with a temperature controller with a magnet, the temperature control is realized by controlling the power-on time, that is, when the electric soldering iron is energized, the temperature of the soldering iron rises. When the predetermined temperature is reached, the strong magnetic sensor reaches Curie point and the magnetism disappears, so that the magnetic core contact is disconnected, and then the power supply to the electric soldering iron is stopped; when the temperature is lower than the Curie point of the strong magnet sensor, the strong magnet returns to magnetism, and the magnetic core switch is attracted The permanent magnet in the circuit makes the contacts of the control switch connected and continues to supply power to the electric soldering iron. This cycle goes on and on, and the purpose of temperature control is achieved.
4. Tin-absorbing soldering iron
Tin-absorbing soldering iron is a desoldering tool that integrates a piston-type tin absorber and an electric soldering iron. It has the characteristics of convenient operation, flexibility and wide application range. The disadvantage of this soldering iron is that it can only desolder one solder joint at a time.
