The invention relates to a driving motor of an
electric vehicle, in particular to a motor of an
electric bicycle and an
electric motor cycle which can realize automatic stepless speed change. The driving motor is characterized in that a permanent brushless speed-changing motor consists of a motor, a centrifugal rotating speed sensing magnetic adjusting mechanism and a speed
reducer; one end of a
motor shaft is connected with a flux shunt 2 which rotates with a rotor, and a spring is arranged between the flux shut 2 and the rotor; the other end of the
motor shaft is connected with a thrust disc 10 which is a
conical surface round disc; a plurality of wedge-shaped spaces distributed radially are formed between the inner surface of the round disc and a bracket 8; the middle part is placed with a centrifugal roller 9; and the
motor shaft 1, the rotor bracket 8, the centrifugal roller 9 and the thrust disc 10 form a centrifugal mechanism. Compared with the prior art and mechanical shift-changing regulation, the driving motor adopts continuous stepless speed regulation, has higher efficiency than that of the mechanical CVT stepless regulation (the efficiency of 60 percent to 70 percent)by more than 20 percent, and is more suitable for the common hidden
board type rotor compared with the
electric control weak
magnetism ratio. The basic method is as follows: a flux shut mechanism is added in the motor so as to achieve the purpose of increasing the speed by weak
magnetism and realize ideal driving characteristic. Due to simple mechanism and reliable working, the driving motor has very wide application prospect.