speedometer and tachometer combo

• 2021-12-30

The tachometer measures the engine speed, and the speedometer shows the real-time speed of the vehicle. Tachometer is one of the necessary instruments in machinery industry, which is used to measure the speed, linear speed or frequency of motor. The speedometer is used to check the driving speed. It supports miles / hour or kilometers / hour. The following is the difference between automobile tachometer and speedometer:

1. The speedometer reflects how many miles the vehicle runs per hour, and the tachometer reflects how many revolutions the engine rotates per minute;
2. Speedometer refers to the driving speed of the vehicle, generally within the range of 0-300km / h;
3. The tachometer refers to the engine speed, which is generally 0-8000r / min.

The most conspicuous thing in the dashboard is the speedometer, which indicates the speed of the car per hour, in km / h. The speedometer actually consists of two meters, one is the speedometer and the other is the odometer.

The traditional speedometer is mechanical. A typical mechanical odometer is connected with a flexible shaft. There is a steel cable in the flexible shaft, and the other end of the flexible shaft is connected to a gear of the transmission. The gear rotation drives the steel cable to rotate, and the steel cable drives a magnet in the odometer cover ring to rotate. The cover ring is connected with the pointer and the pointer is placed at the zero position through the hairspring, The rotation speed of the magnet causes the change of the size of the magnetic line of force, the balance is broken, and the pointer is driven.

The speedometer is simple and practical, and is widely used in various types of cars. With the development of electronic technology, electronic speedometers have been used in many car instruments. The common one is to obtain signals from the speed sensor on the transmission and deflect the pointer or display numbers through the change of pulse frequency.

The tachometer unit is 1 / min1000, which shows how many kilorevolutions the engine rotates per minute. The tachometer can visually display the speed of the engine under various working conditions. The driver can know the operation of the engine at any time, cooperate with the transmission gear and throttle position to keep it in the best working state, which is good for reducing fuel consumption and prolonging the service life of the engine.

The tachometer is generally set in the instrument panel and placed symmetrically with the speedometer. The tachometer works according to the magnetic principle. It receives the pulse signal generated when the primary current in the ignition coil is interrupted and converts this signal into a displayed speed value. The faster the engine speed, the more pulses generated by the ignition coil, and the greater the speed value displayed on the table.

The speedometer and tachometer combo, they are same important.