The structure, type and principle of electric soldering iron
Electric soldering iron is an essential tool for electronic production and electrical maintenance. Its main purpose is to weld components and wires. According to the mechanical structure, it can be divided into internal heat type electric soldering iron and external heat type electric soldering iron. Tin-type soldering irons are divided into high-power soldering irons and low-power soldering irons according to different uses.
Introduction to the structure of electric soldering iron
The external heating electric soldering iron is composed of a soldering iron tip, a soldering iron core, a shell, a wooden handle, a power lead, a 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 component 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 irons, commonly used are 25W, 45W, 75W, 100W, etc. The higher the power, the higher the temperature of the soldering iron tip.
The internal heating electric soldering iron is composed of a handle, a connecting rod, a spring clip, a soldering iron core, and a 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. The rear end of the internal heating type electric soldering iron is hollow, used to be sleeved on the connecting rod, and fixed with a spring clip. When the soldering iron tip needs to be replaced, the spring clip must be withdrawn first, and the front end of the soldering iron tip should be clamped with pliers. Pull it out slowly, remember not to use too much force, so as not to damage the connecting rod.
Types of Soldering Irons
1. External heating electric soldering iron: It consists of a soldering iron head, a soldering iron core, a shell, a wooden handle, a power lead, a 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 component 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 irons, commonly used are 25W, 45W, 75W, 100W, etc. The higher the power, the higher the temperature of the soldering iron tip.
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 common 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. The rear end of the internal heating type electric soldering iron is hollow, used to be sleeved on the connecting rod, and fixed with a spring clip. When the soldering iron tip needs to be replaced, the spring clip must be withdrawn first, and the front end of the soldering iron tip should be clamped with pliers. Pull it out slowly, remember not to use too much force, so as not to damage the connecting rod. 3. Constant temperature electric soldering iron: The electric soldering iron is equipped with a temperature controller with a magnet in the constant temperature electric soldering iron head to control the power-on time to achieve temperature control, that is, when the electric soldering iron is energized, the temperature of the soldering iron rises. When it reaches the predetermined temperature When the temperature is lower than the Curie point of the strong magnet sensor, the magnetism disappears, so that the contact of the magnetic core 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 resumes. It is magnetic, and attracts the permanent magnet in the magnetic core switch, so that the contact of the control switch is 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 electric soldering iron: It is a desoldering tool that integrates the piston-type tin-absorbing device and the electric soldering iron into one. It has the characteristics of convenient use, flexibility and wide application range. The disadvantage of this soldering iron is that it can only desolder one solder joint at a time.
How a Soldering Iron Works
Apply alternating current to both ends of the soldering iron core through the power cord. Since the soldering iron core belongs to a heating resistance wire, it can directly convert electric energy into heat energy, and then conduct heat energy to the soldering iron tip through heat conduction, and it can be used after heating. for welding.
The temperature control range of the electric soldering iron is 100 ℃ ~ 400 ℃, the temperature adjustment mark indicates low, medium and high positions, the temperature control accuracy is nominally ±5%, and a thermocouple sensor is used. The control circuit adopts the direct step-down, filter and stabilized power supply scheme of the AC mains.
