Why electric drills do not use brushless motors?
Finally, the system complexity. The power supply process of brushless motor is ac - DC - AC. It needs to be rectified before inverting. High power rectifiers and inverters are expensive, complex and unreliable processes that can also heat your hands. The current electric drill only need to use the switch control, on-off and power is enough.
The second is the torque problem. Although brushless motors have the advantages of long life and low noise efficiency, these advantages are not useful in electric drills. It is limited by the weaker magnetic force of the permanent magnet, and the brushless motor can not produce large torque, which is very fatal. Because an electric drill requires great torque to overcome the resistance of the drill.
First of all, the cost problem, brushless motor drive device is very expensive (brushless motor itself is cheap), electric adjustment + motor one hundred to hundreds of pieces uncertain. Now, the AC excitation motor used by the electric drill doesn't use any microelectronic chip. It only uses copper wire and silicon steel sheet, which is very cheap.
