The development of magnetic tiles
2022-02-23 10:001) permanent magnet motor is divided into permanent magnet DC motor and permanent magnet AC motor.
1.1 Permanent magnet AC motor refers to the multi-same step motor with permanent magnet rotor, which previously mainly used ferrite and aluminum, nickel and cobalt magnetic tiles. As the power requirements get higher and higher, ferrite and aluminum, nickel-cobalt cannot meet the requirements due to the low magnetic energy product. Now NodFeB magnetic watts are widely used in the field of high-power synchronous motors and generators.Of course, neodyFeB magnetic tile, due to the precious rare earth resources, the price of raw materials doubled, its production cost and production price will continue to rise in the future, affecting its large use in some low-end fields.The negative temperature coefficient of NFEB permanent magnet itself, the low Curie temperature, also limits the response at high temperature.
1.2 Permanent magnet DC motor is also divided into brushless motor and ordinary DC motor with commutator, in which its application situation is judged from the shape and pole number of the magnet
In ordinary DC motors, 2 poles and 4 poles are mostly used, and magnetic tiles are basically used as motor stator. Most micro DC motors use ferroxy magnetic tiles, mainly in the field of toys, home appliances and automobiles.When a brushless motor uses a magnetic tile as a stator, it generally exceeds 6 poles, so its center angle is far less than the magnetic tile used for an ordinary DC motor.However, when the magnetic tile serves as the rotor of the brushless motor, it can have more than 4 or 6 poles. For the 4 poles, the rotor is the external surface magnetization, and due to a circle, its center angle is close to 90, which can be different from the ordinary DC motor.
2), magnetic tile according to different application field, performance and magnetic field, as a rotor field, sine wave, according to motor output requirements, spark and noise, and the waveform is mainly saddle shape with large output, but high spark noise and no-load current.In order to improve the vibration noise, change spark, reduce no-load current, magnetic steel shape size, mold design should be carefully designed, among which unequal thick magnetic tile has been widely used, its principle is to make the arc air gap magnetic field waveform inside the magnetic tile tend to flat top wave.
Special uses of 3,: the earliest enterprises to do ferroxy magnetic tile in China, such as Sichuan 899 (Yibin Jinchuan Electronics Co., Ltd.), Meizhou Magnetic Materials Factory, Guangdong Province. In the popularity of magnetization cup in the 1980s and 1990s, magnetization tile was used as the magnetic field source of magnetization cup.At that time, the domestic demand for ferroxy magnetic tile was also very small.