The vehicle speed sensor

Traditional mechanical speedometer , which connect a flexible shaft , flexible shaft has a wire rope , the other end is connected to the transmission shaft one gear , the gear driven rotary rotating wire rope , wire rope driven speedometer cover a circle rotating the magnet ,Engine Temperature Sensors cover ring and by the pointer spring coupled into the pointer to zero, rotation speed of the magnet field lines due to the change in size , the balance is broken , the pointer is therefore driven .In modern automotive field , using more electronic tachometer , with pointer and LCD digital display , the table has a digital integrated circuit , it will convey the ignition coil voltage pulse has been calculated over the rear drive or digital display pointer moves .Another tachometer pulse signal is obtained from the generator to the tachometer speed value is displayed after the circuit , but due to the alternator belt slippage and other factors , the value is not accurate .