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analog bicycle speedometer mph
For analog bicycle speedometer mph:
1. Meter head: it looks like an electronic timer, with liquid crystal display, keys, metal contacts, etc. it is the most important part of the code table.
2. Watch base, connecting line and sensor: the watch base is usually placed on the handlebar or the handlebar of the car to fix the meter.There is a wire on the watch base of the wired code watch to connect the watch base with the inductor installed on the front fork. The wireless code meter is not connected, and the sensor transmits data to the meter by transmitting wireless signals.
3. Induction magnet: it is installed on the spokes of the front wheel, and the position keeps a corresponding relationship with the inductor installed on the front fork. The meter head calculates the speed and other data through the interval between two consecutive passes of the induction magnet through the inductor.
4. Pedaling frequency device (non-standard accessories): the middle and high-end code meter has the function of calculating pedaling frequency, that is, the frequency of pedaling by the driver. Common frequency pedals include wires, inductors and induction magnets. The wires are used to connect the watch base and the inductors installed at the rear triangle of the frame (the rear triangle here refers to the pipe parallel to the central axis). The induction magnets are often installed at the crank. The positions correspond to the inductors and the working principles are the same as before.
5. Code meter lighting (non-standard accessories): installed on the meter base to illuminate the meter at night.
Working principle editing
When the rim rotates, the sensor captures the information brought by the induction magnet and transmits it to the code meter through the sensor line. The host code meter calculates the speed, mileage and other information after processing it.In a more popular way, a magnet is installed on the front wheel, and a sensor is installed on the front fork. Once the wheel rotates, the magnet passes by the sensor once, and the code meter counts one turn. According to the preset wheel parameters, the code meter calculates the speed and distance. Simply put: the working principle is to measure the speed by multiplying the rotation speed of the wheel by the circumference of the wheel during riding.
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