China Neodymium And Ferrite Magnets Manufacturer & Supplier 
Single pair pole (1 pair pole) radial magnetic ring is a very common type of ring-shaped permanent magnet. It is widely used in angle detection, position detection, Hall sensors, rotary encoders, medical equipment and various types of automated equipment. The following is a detailed introduction to this type of magnet.
Single pair pole radial magnetic ring refers to a ring-shaped magnet that has only one N-pole and one S-pole along its circumference, i.e. only one pair of magnetic poles (two poles in total). The N-pole occupies half the circumference, whilst the S-pole occupies the other half. The distribution of the magnetic poles is shown in the figure below.
Magnetic Pole Distribution of a Single Pair Pole Radial Magnetic Ring
What are the characteristics of a single pair pole radial magnetic ring?
More uniform magnetic field (only one N/S switch across the entire 360°)
Output waveform close to an ideal sine wave
Simple installation and commissioning
Relatively simple magnetisation process
Less prone to magnetic pole interference
The single-pole pair magnetic ring itself merely provides a stable magnetic field; the actual detection is performed by Hall sensors, AMR magnetic sensors, TMR magnetic sensors, GMR magnetic sensors or magnetic encoder ICs. As the magnetic ring rotates, the N-pole gradually approaches the sensor, causing the magnetic field to gradually weaken; as rotation continues, the S-pole approaches, and finally the N-pole is reached again. Throughout the entire 360° rotation, the magnetic field exhibits an approximately sinusoidal variation. Consequently, it is possible to detect both the angle of rotation and the direction of rotation; this is a key reason why many magnetic encoders recommend the use of single-pole magnets.
As for magnet materials, different magnetic materials can be selected depending on the application. Sintered neodymium-iron-boron is the most commonly used, offering a strong magnetic field and high sensitivity. Next is sintered ferrite, which is low-cost and suitable for standard Hall effect detection, flow meters and household appliances; in some cases, injection-moulded ferrite may also be required.
The above provides an overview of single pair pole (1 pair pole) radial magnetic rings. For custom orders, please provide details such as the magnet’s outer diameter, inner bore, thickness, magnetic material, operating temperature and magnetic field strength.
One pair of magnetic rings;
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