Slotless brushless motor change on the product performance after the
a. High efficiency:
one of the reasons is slotted motor iron core laminations within the circle (External rotor motor is cylindrical)Structure is the arrangement of teeth and slots alternate with, coil embedded with groove, use tooth form magnetic circuit magnetic flux, because the tooth is very narrow, tooth flux density is high, the tooth of fever is serious, so the tooth of loss is large, without slot machine without this part of the loss;
the second reason is the copper wire and air permeability, phase field lines through the magnetic resistance is very big, the motor of the later is bound to increase the magnetic circuit is magnetic resistance, therefore, relatively slotted motor, the magnetic circuit of the motor is weaker, natural eddy current loss of the motor is relatively small; Third reason is the core laminations cancel after the tooth, expanded winding arrangement of space, this can or bold section of copper wire with progressive motor current level, or increasing the turn of winding of motor voltage grade, or for the above both Goodyear, inductive synchronous brushless motor car ultimate than slotted motor power/volume ratio and the loss is changed, the wastage of the same size, high efficiency of power supplied by nature. So, the motor of the progress since efficiency is don't ask, don't know.
2. Light weight, small volume.
3. Overload ability: dongguan motor known brushless direct current motor overload capacity is very strong, torque is proportional to the current, the overload capacity is through promised to overload current to appraisal. Grooved structure compared with no slot structure, however, the difference is bigger, because the slotted structure of small magnetic air gap, the dongguan yuntai brushless motor, the magnetic poles without a jacket when it is mechanical air gap, the magnetic poles are sheathed when namely is mechanical air gap and a sheath thickness, unilateral magnetic air gap can be searched with different size the product data in 0. 04∽0. 80 mm scope changes, in such a small magnetic air gap of winding armature reaction after the electricity resistance ability is limited, so the size of the overload current to limit winding, lest because of overload current permanent magnet poles of the magnetization and magnetic, leading to loss of motor function. Structure without slot is different, unilateral magnetic air gap can be searched with different size the product data changes within the range 3 ∽ 12 mm, greater reluctance, effectively curb the overload current to magnetic effect, winding damage due to fever was the main cause of limiting overload current, so the motor instantaneous overload of the structure is more than 10 times is a common thing, any motor, including the overload capacity is unmatched by slotted brushless dc motor.
4. Low vibration, low noise, smooth operation:
one of the reasons is that there is no groove which is no teeth, no regular slotted motor & other; The cogging effect & throughout; ——Permanent magnet poles in the process of rotation for the teeth, and the high frequency vibration phenomenon of the groove;
for another magnetic air gap is big, in the process of manufacturing, the rotor's not alignment relative to the magnetic air gap ratio is greatly reduced, thus effectively suppresses the slotted in the motor cannot be ignored that the influence of the unilateral magnetic pull, brushless dc motor factory, make the motor can run smoothly;
the third reason is winding inductance is small, than those with low a level number slot motor, so small electric time constant, when the controlled reaction speed, reduce the degree of electromagnetic vibration. These factors is slotless motor low vibration, low noise, smooth operation of internal causes.
