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700r4 speedometer drive gear
How the 700r4 speedometer drive gear: 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).
The measurement of vehicle speed is realized by the vehicle speed sensor. The driving speed of the vehicle is closely related to the radius of the wheel and the structure of the rotating shaft. Since most parts of the car are iron elements, when a Hall sensor that can detect the change of magnetic flux is installed at its corresponding position, the output of the sensor will change continuously with the rotation of the rotating shaft during the driving of the car, and the final speed passes through A gauge needle is reflected on the instrument panel.
There are two main reasons why the speed value displayed by the car speedometer is larger than the actual speed: for safety reasons and errors in the calculation process, this is specified according to the number of accidents and road conditions. Overtake. In addition, the speed measuring device on the car may have a delay. In order to avoid the instantaneous vehicle speed being too high, when the displayed value is larger than the actual value, it can prevent the car from suddenly accelerating and causing danger.
In addition, the state stipulates the relationship between the indicated vehicle speed and the actual vehicle speed: 0<=indicated vehicle speed-actual vehicle speed<=actual vehicle speed/10+4km/h. That is to say, the displayed speed cannot be less than the actual speed, and it cannot exceed 10% of the actual speed plus 4km/h. In layman's terms, if the actual speed is 100km/h, then the speedometer shows that the speed is between 100 and 114km/h.Speaking of which, I think everyone knows that the speed on the car's dashboard is higher than the actual speed. The state has such regulations, and the manufacturers also set them in this way. They are all reasonable, and the purpose is to drive safely. In addition, don't "take the loop" because of this, thinking that you can "overspeed" at ordinary times, and remind everyone not to do this. The error between the speedometer speed and the actual speed is only a range, and you don't know how much. Speeding at random is both punishable and very dangerous.
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