The principle of intelligent and intelligent dual-control electric bicycles is basically the same. All of them are composed of car body, battery, transmission part, microcomputer controller and force measuring and speed measuring sensing part (commonly known as torque sensor). When riding intelligently, the pedaling force of people is measured by the sensor, and the motor outputs corresponding power after being processed by the microcomputer, which makes people riding very labor-saving. The greater the pedaling force, the greater the output power of the motor, that is, electric power assistance, and vice versa. #W4a#H
The biggest advantage of intelligent riding is safety, power saving and easy to use. Riding an intelligent electric bicycle is exactly the same as riding an ordinary bicycle, but with the help of electricity, riding is easier and more labor-saving. Most countries in Europe, America and Japan need intelligent electric bicycles. Among them, Japan only allows smart electric bicycles to go on the road, and has formulated very strict regulations on the requirements of smart electric bicycles. Specifically: 1) In any road condition, when the vehicle speed is less than 15km/h, manpower: electric assistance ≥ 1, that is, electric assistance is not allowed to be greater than manpower, but it can be close to manpower. 2) Under any road conditions, when the vehicle speed is greater than 15km/h, the electric power assist will decrease with each increase of 1 km/h; 3) When the vehicle speed is less than or equal to 24 km/h, turn off the electric power assist system of the whole vehicle. 4) The electric power assist system works according to the above requirements within 1 second after people pedal; After people stop pedaling 1 s, the electric power assist system of the whole vehicle is turned off. 5) In order to save electric energy, after the intelligent electric assisted bicycle stops running for a certain period of time (usually 3-5 minutes), the whole vehicle is in a dormant state. 6) The continuity of riding must be ensured, and there can be no intermittent phenomenon of electric power. 5 & amp
In order to realize the above-mentioned intelligent riding, the intelligent electric assisted bicycle must have a torque sensor and a microcomputer controller. Loaded vehicle
Intelligent dual-control electric bicycle is a new type of bicycle that can ride intelligently and drive manually. Like the intelligent electric bicycle, it also needs a torque sensor and a microcomputer controller. Intelligent riding is the same as pure intelligent electric bicycle, and manual driving is the same as pure electric bicycle. The only difference between it and smart car is that the software and hardware of microcomputer controller are slightly different. Intelligent dual-control electric bicycle is a product that is very suitable for China's national conditions and the battery is not completely qualified at present. Pure electric driving and pure intelligent driving will make people feel very tired, and it is easy to use them alternately; Intelligent driving when starting, uphill, against the wind and accelerating reduces the use of large current and saves electricity, which can not only extend the cruising range, but also increase the driving range; When the road conditions are good and there are few people, drive by hand; In the case of bad road conditions and crowded people, intelligent riding is very safe. Intelligent dual control, if properly designed, can realize seamless switching between intelligent and manual control, which is very convenient to use. This kind of electric bicycle is a safe and energy-saving product if it is used in large and medium-sized cities in China. The core components of intelligent electric bicycles and intelligent dual-control electric bicycles are torque sensing components and microcomputer controllers. The hardware and software design of microcomputer controller is beyond the scope of this paper. The principle and some structures of the torque sensor are introduced below. Torque sensor is a force measuring device in intelligent and intelligent dual-control electric bicycle, and its function is to measure people's pedaling force. So its installation position must be related to the pedal force of people. In riding, what places are related to people's pedaling power? p^>； 2y
Installation position and related scheme of torque sensor. A. pedal: pedal torque sensor. A pressure sensor is installed on the pedal, and manpower is exerted on the pedal. The pressure sensor will output a voltage signal that changes with manpower, and the voltage signal will be transmitted to the microcomputer controller through a set of carbon brush mechanism, so as to realize the proportional output of manpower and electricity. Advantages: simple structure and low cost; Disadvantages: the transmission line is long and there are many unreliable factors, so it is not suitable. B crank: crank torque sensor. A strain gauge is mounted on the crank. When human steps on the crank, the crank is slightly deformed, and the strain gauge outputs the corresponding voltage signal. The output signal varies with manual work. The output signal is transmitted to the microcomputer controller to realize the proportional output of manpower and electricity. The advantages and disadvantages are the same as above, which is not desirable. Sprocket: Sprocket torque sensor.
The sprocket disc is designed as a driving and driven double sprocket. The driving wheel is fixed with the crank, and the driven wheel drives the chain. The driving wheel and the driven wheel are connected by a spring. When people pedal, the driving wheel drives the driven wheel to move through the spring. At this time, there will be angular displacement between the driving wheel and the driven wheel. The angular displacement is measured, and the angular displacement signal is processed by microcomputer controller to realize the proportional output of manpower and electricity. This scheme is completely feasible. D. center shaft: center shaft torque sensor.
The center axis sensor is the place where many manufacturers place torque sensors. The schemes represented by Yamaha, Giant and Merida in Taiwan Province Province are not described here. Next, a scheme of shaft torque sensing is introduced in detail. The following figure is a schematic diagram of the original center shaft sleeve of the eccentric shaft torque sensor for the eccentric shaft sleeve of intelligent electric bicycle, which was tested by 1995 Tsinghua Japanese National Safety Committee. When riding, the central shaft rotates in the middle shaft sleeve under the action of the pedal and crank of the foot. At the same time, the central shaft and the intermediate shaft sleeve are subjected to a downward force F as shown in Figure 3: Schematic diagram of the central shaft torque sensor, which will act on the eccentric shaft sleeve. The eccentric shaft sleeve is installed in the five-way pipe. Because the intermediate shaft and the intermediate shaft sleeve are not concentric with the eccentric shaft sleeve, under the action of this force F, the eccentric shaft sleeve will rotate in the five-way pipe to form an angular displacement. When the human stops pedaling, the eccentric shaft sleeve is reset under the action of another elastic element. The angular displacement of eccentric shaft sleeve changes with the pedaling force of people. This changing angular displacement is measured and transmitted to the microcomputer controller through voltage signals, thus realizing intelligent riding. Advantages: compact structure, intelligent sensing can be realized only by a big five-way central shaft. Disadvantages: the eccentric shaft sleeve is complicated to process and has certain precision requirements; In addition, there are six bearings with different sizes, which makes the cost high, but this is only a small disadvantage. The biggest disadvantage of this scheme is that the rotation of eccentric shaft sleeve drives the sprocket disc to produce micro-displacement before and after, which will cause the chain to tighten. E-chain: pressure chain torque sensor. The pressure chain torque sensor of sprocket lever mechanism is a sensing scheme with simple structure, low cost, reliable performance, light weight and high use value for flat fork guide wheel. This is a cheap and good product. The concrete scheme of the chain flywheel of the displacement measuring device is obvious to all. Fig. 4: schematic diagram of pressure chain torque sensor not mentioned here. Just to remind you here, some manufacturers have also designed the pressure chain torque sensor, but in use, the vibration of the chain produces displacement, which leads to the false identification of the torque sensor. The graphic scheme adopts the lever principle to control the up-and-down movement range of the guide wheel under the action of force within 2 ∽ 3 mm. Through the amplification of the lever principle, the displacement received by the displacement sensing device is about10 ∽15 mm. Therefore, misoperation cause by chain jitter can be effectively overcome. The technology of pressure chain torque sensor is mature and its application prospect is broad. Flywheel, rear axle and hub: rear torque sensor. The scheme of placing torque sensors at flywheel, rear axle and hub can be collectively called rear torque sensor. The rear torque sensor generally adopts the scheme of driving wheel and driven wheel. The driving wheel is connected with the flywheel, the driven wheel is connected with the rear wheel, and an elastic element is connected in the middle. The principle is basically the same as that of sprocket torque sensor. When the rear torque sensor is placed in the hub, the driving wheel is connected with the flywheel, the driven wheel is connected with the outer rotor of the hub, and the elastic element is in the middle. Sanyo and Tsinghua both developed and produced motor wheels with built-in torque sensors, and applied for related patents.
. The basic principle of torque sensor is briefly introduced above. The specific application depends on the specific layout and quality of the vehicle, the price and the requirements for force measurement to choose which scheme is the most suitable, and it cannot be mechanically copied. In a word, it is very necessary to know some knowledge of torque sensing. Now some manufacturers claim to have mastered the technology of intelligent electric bicycles, but in fact they don't know the knowledge of torque sensing. Their so-called intelligent technology is false intelligence. Riding with false information feels bad. If China's electric bicycles want to go global, they must master intelligent technology and torque sensing technology. At the same time, in order to produce qualified intelligent electric bicycles, we must master the microcomputer control technology. Only in this way can we become a real electric bicycle power and make our own contribution to the electric bicycle industry in China!