① Brushless DC fan structure: mainly divided into rotor, stator, outer frame, motor (motor) and other fragmentary parts.
First, the fan rotor part:
Including the fan blades, is the core that generates the air flow. The heat dissipation fan shaft is used to support the rolling of the balanced fan blades, the rotor magnetic ring and the permanent magnet, the key to promote the switching speed of the magnetic stage, the outer frame of the magnetic ring, and the fixed magnetic ring.
Second, the fan stator part:
Including support springs, separate bearings, balance shafts, bearings that provide high-speed, low-friction, long-life rotation, retaining rings, fixed nodules, rotating entire parts, motor parts, production rotation direction, and key rotation speed.
3. cooling fan frame:
Support fan motor and diversion.
Fourth, the fan motor part.
Including circuit board, control energy consumption and signal in and out, silicon steel plate (ie stator magnet, upper winding coil) to produce magnetic stage propulsion switching, silicon steel plate upper and lower cover fixed insulator.
② Basic knowledge of cooling fan.
First, the fan size:
Fan size is generally expressed by the fan outside and product thickness, the unit is mm. Fan specifications and models are usually named after the size. For example, the 6010 in AD6010 represents 60*60*10mm.
2. rated voltage: it is the voltage value under the rated operation of the fan. The common DC fan voltage is generally 5V, 12V, 24V, 48V, etc.
Third, fan speed: The fan rotation speed is rpm (per minute), which is an important parameter of the fan. It can bring high-speed table with large air volume. Manufacturers often standardize their products into ultra-high (U), high (H), medium (M), low (L) and other products for users to choose according to their own situation.
Fourth, air volume: quantitative fan capacity indicators. The unit is cubic feet per minute (CFM), but some local signs are in cubic feet per minute (CMM),1CMM = 35.31CFM.
Fifth, wind pressure: the ability of Peugeot wind flow to overcome wind resistance. The unit that directly affects the effect of ventilation or heat dissipation is mm-h2o, and the unit of some local signs is inh2o,1mmh2o = 0.03939 inh2o.
Sixth, noise value: is an important parameter. The unit is DBA (decibel). Although it has nothing to do with the effect of ventilation and heat dissipation, it has high requirements for different environments.
Seventh, bearing system: This configuration is the soul part of the fan, which is directly related to the mechanical service life of the product. Usually divided into ball bearings and oil bearings.
Eighth, the joint: is an important detail on the fan, often divided into endless, 2P, 3P, large 4P, etc.
③ DC brushless fan circuit.
Micro DC motors are widely used in household appliances, especially in computers. The new DC fan adopts a brushless structure, which overcomes the shortcomings of the traditional commutator (brush) motor, such as easy wear, high noise and short service life. Several fan circuits drawn according to real objects.
The principle of brushless DC fan.
The pulse generator based on Hall element has simple structure and good performance. The electromagnetic environment of the locomotive electrical system is harsh, and the product itself is required to have a strong anti-interference ability.
The brushless DC fan is driven by a brushless motor and has no electromagnetic interference. It completely overcomes the shortcomings of electromagnetic interference, high noise, and short mechanical life. It is widely used in electronic and electrical applications that require forced heat dissipation.