Electric vehicle knowledge-drive mode and motor

Apart fromWheel hubWhat are the other ways to drive mode? Most electric bicycles in Japan use a central axis drive mode. There are two main reasons: First, Japan stipulates that electric bicycles must rely on human power to output auxiliary power, so pedal force must be measured, and a force measuring mechanism must be installed on the central axis. (sensor), the driving mechanism and the force measuring mechanism are integrated. Second, Japan lacks the resource advantage of manufacturing high-efficiency disc motors. Compared with domestic electric wheels, some Japanese-made electric hubs are inferior in terms of size and weight (large appearance and heavy weight).There is also a friction transmission method, that is, through andtireThe friction transmits power, its advantage is through the power wheel andtireIts own diameter ratio forms a deceleration, and a deceleration mechanism is omitted. The output of the motor directly drives the tires. However, the weakness is also very obvious. Bicycle tires are often out of round or deformed. This situation directly affects the transmission efficiency and the reliability of the mechanism.Therefore, it is necessary to use thickened and widened special tires and steel rims to prevent them from deforming or out of rounding, which will result in daily maintenance and replacement.AccessoriesVery inconvenient. Compared with the two methods you mentioned, what are the advantages and disadvantages of the wheel drive method? There are many advantages. One is that the electric wheel hub is relatively independent, closed, and will not be interfered by other parts, and has good reliability (for example, the bottom bracket method relies heavily on the manufacturing precision of the frame, and the friction transmission must have good installation accuracy and be compatible with tires and steel. The circle is directly related); the second is the higher transmission efficiency; the third is the easier maintenance. The main disadvantages are: one is the high manufacturing cost; the other is the appearance is too simple, making people doubt its value, many consumers can not understand why such a small wheel is worth so much money? Some dealers have to falsely claim that "this is imported" to eliminate the psychological barriers of customers. In fact, electric wheels are only exported from China to foreign countries, and there are no imported electric wheels. What are the characteristics of brushless motors? Since the brushless motor has no brushes, its biggest advantage is that the brush wear is eliminated fundamentally, the brushes do not need to be replaced due to expire, and the noise is very small. However, the current manufacturing cost of brushless motors is relatively high, and some manufacturers are unwilling to use them. What are the advantages and quality hazards of brushed motors? As the name implies, the main hidden danger of brushed motors is "brush wear" because of brushes. Users should note that brushed motors are divided into two types: toothed and non-toothed motors.At present, many manufacturers choose a brushed and geared motor, which is a high-speed (High Speed) motor. The so-called "toothed" means that the electricRotating speedTurn down (because the national standard stipulates that the speed of electric vehicles should not exceed 20 kilometers per hour, the motor speed should be about 170 rpm). Because the high-speed (High Speed) motor decelerates through gears, the characteristic is that the rider feels strong power when starting, and has a strong climbing ability. However, the electric wheel hub is closed. It is only filled with lubricant (oil) before leaving the factory. It is difficult for users to carry out daily maintenance. Moreover, the gear itself is also mechanically worn. The lack of lubrication in about a year leads to increased gear wear and increased noise. The time current also increases, which affects the life of the motor and battery. Another brushless gearless motor is a low-speed motor without a gear reduction mechanism. Its dynamic performance and climbing ability are relatively weak, but it is safe to operate (small impact (Impuise) force) and less brush wear (its The low-speed characteristics determine that the wear of the brush is only about 1/16 of that of a brush-toothed motor), and less noise (due to the absence of a gear reducer) is its significant advantage.