According to data released by the China Association of Automobile Manufacturers, China produced and sold 22.1168 million and 21.9841 million vehicles in 2013, up 14.8% and 13.9% year-on-year respectively, of which passenger cars accounted for more than 17 million, and it is expected that the total will exceed 24 million in 2014. This is only the data for China, and the sales of other countries should not be underestimated.

Such a huge number means the opening up of a new market. Car air purifiers are undoubtedly the most urgently needed and popular products nowadays. Unlike household air purifiers that need to purify a large space, car air purifiers only need to purify the air in about 6 cubic meters of space in the car, so portability, plug-and-play, and compactness will become its most attractive features to customers. At the same time, because it is used in a closed space, the requirements for noise are also very strict. As the core component of the purifier, the selection of brushless motors is very important. Based on our experience with purifiers and brushless motors, the most suitable model is the outer rotor brushless motor B3020S . Recommended reason:

1. Small size, save space. The overall size of the car air purifier is not large, and the internal space is very small. Hengqu's outer rotor brushless motor B3020S has an outer diameter of 30mm and a height of only 20mm. Due to our special fixed design, the bearing position is low and the output shaft is not exposed, which saves space better.

2. Built-in DC12V driver, no need for rectification and voltage reduction, plug and play. The direct output current inside the car is DC12V, so commonly used car chargers and other products are all DC12V specifications for ease of use. As a car air purifier, the working power also comes from the car, so it is necessary to design the entire product to be DC12V. The internal brushless motor is also DC12V, which will save a lot of redundant circuit design.

3. Ultra-quiet, guarantee of quiet space. At the beginning of its design, B3020S was mainly designed for low-power bladeless fan applications. A lot of effort has been put into the quietness. With ultra-low noise and excellent electromagnetic compatibility (EMC), it is the best choice for small space air purification equipment.

B3020S has a very obvious disadvantage, that is, due to its size, its power is very small and it cannot load large blades. But after encountering the car air purifier, all of this is no longer a problem. The car air purifier itself purifies about 6 cubic meters of space. According to our evaluation, it only needs full DC12V, 4000RPM, 1.5mNm load performance, and the estimated power is less than 1W, which is exactly within the performance range of B3020S. Therefore, the B3020S outer rotor brushless motor is the most suitable motor for car air purifiers.