① Motor with brushed disk winding. The brushed disk winding motor is bonded with rare earth materials on a cylinder body, and the disk winding made of enameled copper wire is placed in the cylinder body to form a rotor. The motor phase is adjusted by mechanical inverter. The mechanical inverter adjusts the voltage phase by friction between a fixed carbon brush and a rotating copper commutation surface. The brushes of this kind of motor have been worn out during use, and the service life of the motor is difficult to exceed 2000h. At the same time, due to the high speed of the motor, a two-stage gear reduction must be adopted. This brings about two problems. One is that the noise is large, and the other is the efficiency loss. The rated efficiency of the motor after deceleration can often only reach 68%. ~72%. The capacity of the battery used in electric bicycles is limited, generally 36V/12Ah. If the motor efficiency is not high, it will increase the power consumption and affect the continued mileage.
②Motor with brush printing winding. The brush printed winding motor uses printed copper foil as the winding, and the weight of the motor is reduced. Since this motor is all produced on an automatic production line, the process is reliably guaranteed, so that the life of the motor is increased to 3000h, the noise is greatly reduced, and the efficiency is increased to 72% to 76%. But this kind of motor has "buzzing" high-frequency noise, and the efficiency is still not ideal after gear reduction. The use of the brushed inverter makes the motor's lifespan unable to be improved.