Ear charging induction coils are widely used. There are various coil shapes and winding methods when making ear charging induction coils. Different winding equipment will be used to wind different coils. Due to the need for different charging equipment, There are many styles and types of coil products, and the applicable wireless charging equipment is also very wide. Different ear charging induction coils are designed according to the needs of users.
When winding the ear charging induction coil, the winding method should be determined according to the requirements of the wireless charging device circuit, the inductance of the coil and the size of the coil, and then the mold should be made. This is mainly because the size and winding of the transmitting and receiving coils need to be reduced. Therefore, the inductance of the coil is relatively small, about tens of microhenries. In order to improve the transmission power density, it is necessary to use a high-frequency AC signal for power transmission. Here, 640kHz is used. "Skin effect", the current tends to the surface of the conductor. At about 20 degrees, the current depth of the 640kHz high-frequency alternating current in the copper wire is only 0.0825mm. Therefore, in order to increase the surface area of the conductor and reduce the current loss, it is necessary to use multiple strands of yarn Winding the coil. The ear charging induction coil is basically wound from the inside out, so the inner diameter must be determined first. Then the number of layers, height and outer diameter of the coil should be determined according to the inductance value, resistance and other factors.
The ear charging induction coil is suitable for short-wave and medium-wave circuits. Its Q value can reach 150-250, and the stability is high.
After the ear charging induction coil is energized, a magnetic field is formed around it. Make it into a spiral shape. The more turns, the larger the magnetic field range, the more current that passes per unit time, and the stronger the magnetic field. According to the skin of the current In order to improve the space utilization, the wire used in the coil is usually insulated enameled wire.
Wiring is very important when winding wire using automated equipment. For a single wire, the number of turns and layers of the coil needs to be considered. The arrangement of the coils for ear charging induction coils depends on whether the coil is to save space or improve heat dissipation. Usually, several requirements are irreconcilable.