Power inductor and manufacturing method thereof

Abstract

The invention discloses a power inductor and a manufacturing method thereof. The power inductor comprises an inner core and a die-casting body closely coating the inner core, the inner core is of a coil structure wound by an enameled wire and comprises a body and extension portions extending out of the body, the die-casting body is formed by integrally diecasting magnetic metal powder on the inner core, the extension portions expose out of the opposite end faces of the die-casting body, and metal layers are coated on the surfaces of the ends, corresponding to the extension portions, of the die-casting body to coat the ends of the die-casting body so as to form electrodes of the power inductor. By integral die-casing forming of the magnetic metal powder and the inner core, automatic large production can be achieved, and material cost and labor cost are reduced greatly. Besides, a traditional welding process of a coil and electrodes is cancelled, potential quality hazards due to the fact that various problems of welding spots and the like are prone to occur in the traditional process are overcome completely, and insulation property, magnetic shielding property, current resisting property, high-temperature property and cost control of finished products are improved greatly.

Description

technical field [0001] The invention relates to an inductor and a manufacturing method thereof, in particular to a power inductor and a manufacturing method thereof. Background technique [0002] With the rapid development of science and technology, the size of various mobile digital products including mobile phones is getting smaller and smaller. Due to the increasingly stringent control of electromagnetic radiation, cross-interference and electromagnetic pollution brought about by environmental changes (EMC control standards), inductors play an important role in absorbing surges in the circuit, and the current resistance characteristics of power inductors , EMI characteristics can not meet the requirements of the market. Most of the small-sized chip power inductors in the current market are not integrally formed. There are practical difficulties such as low inductance, high current resistance, poor reliability, high temperature, and poor EMI characteristics. At the same t...

AI Technical Summary

Problems solved by technology

Due to the increasingly stringent control of electromagnetic radiation, cross-interference and electromagnetic pollution brought about by environmental changes (EMC control standards), inductors play an important role in absorbing surges in the circuit, and the current resistance characteristics of power inductors , EMI characteristics can not meet the requirements of the market

Most of the small-sized chip power inductors in the current market are not integrally formed. There are practical difficulties such as low inductance, high current resistance, poor reliability, high temperature, and poor EMI characteristics. At the same time, the degree of automation is not high. , its high labor cost is also an obstacle to the development of the industry

[0003] At present, there are power inductor electrodes integrally formed by powder die-casting in the industry. The process adopted is to embed the end of the electrode into the inside of the powder for fixing. Although this method is simple and easy, it also appears in small size (Size below 3*2*1) Difficulties that cannot be realized by technology

Difficulties include: one is that the high-strength enameled wire with a diameter of less than 0.15 cannot be mechanically peeled and welded. Although the self-welding wire with a diameter of less than 0.15 can be welded, the insulation withstand voltage cannot meet the requirements; the second is that due to the small size, the embedded electrode occupies powder. The bulk space will reduce the powder material, the magnetic energy product of the inductance will decrease, and the outer edge of the coil will be occupied by the electrodes, resulting in a decrease in the current resistance characteristics; thirdly, the cost of small-sized electrodes is high, and the consistency of product electrode size and shape is relatively accurate. Low, and it is difficult to achieve fully automated production in large quantities

Images