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How does a car speedometer work
The driving shaft of the speedometer is driven by the transmission or transfer gear through the flexible shaft. The speedometer consists of a permanent magnet fastened to the driving shaft, an aluminum bowl with a shaft and a pointer, a cover, and a dial fastened to the case. When not in operation, the aluminum bowl keeps the pointer at the zero position of the scale under the action of the disc spring (hairspring).
1. When the car is running, the driving shaft rotates with the permanent magnet, the magnetic field lines of the permanent magnet generate eddy currents on the aluminum bowl, and the eddy currents interact with the magnetic field of the permanent magnets to generate torque to overcome the elastic force of the disc spring, so the aluminum bowl has a pointer turn an angle;
2. The speedometer is used to indicate the driving speed and accumulated mileage. It consists of two parts: speedometer and odometer. The driving shaft is driven by the transmission or transfer gear through the flexible shaft;
3. The speedometer consists of a permanent magnet fastened to the driving shaft, an aluminum bowl with a shaft and a pointer, a cover and a dial fastened to the case;
4. When not working, under the action of the disc spring (hairspring), the aluminum bowl keeps the pointer at the zero position of the scale.The function of the speedometer is to indicate the driving speed and the accumulated mileage. It consists of two parts: the speedometer and the odometer. The drive shaft is driven by the transmission or transfer gear through the flexible shaft. The speedometer consists of a permanent magnet fastened to the driving shaft, an aluminum bowl with a shaft and a pointer, a cover, and a dial fastened to the case. When not in operation, the aluminum bowl keeps the pointer at the zero position of the scale under the action of the disc spring (hairspring).To put it simply, a sensor is installed on the output shaft of the gearbox to detect its output speed, transmit the signal to the computer, and the computer will calculate the corresponding speed and then display it on the instrument and this check.
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