Electric horn driving circuit of electric vehicle

Abstract

The invention discloses an electric horn driving circuit of an electric vehicle. An audio generator of an electric horn is designed by utilizing a 555 timer and can output periodic pulse signals to trigger a transistor to run to finally make a horn diaphragm vibrate regularly. In the circuit, when a power supply VCC charges a capacitor C1 through resistors R1 and R2 and the voltage of the capacitor C1 reaches 2 / 3 of that of the power supply, a third pin of a chip outputs high level, the capacitor C1 stops being charged, and when the voltage of the capacitor C1 reduces to 1 / 3 of that of the power supply, the third pin of the chip outputs low level, so that the periodic pulse signals are achieved; meanwhile, a variable resistor R8 is introduced among a seventh pin of the chip and the resistors R1 and R2 so that the resistors R1 and R2 can be adjusted by adjusting the resistor R8, the time of charging and discharging the capacitor C1 is adjusted, and therefore the purpose of adjusting sound production is achieved by changing the duty ratio output by the third pin of the chip.

Description

technical field [0001] The invention relates to an electric horn driving circuit of an electric vehicle. Background technique [0002] Conventional horns are basically pot-shaped electric horns, which mainly include electromagnet coils, diaphragms, contacts and other components. The sounding principle is basically to control the contact action of the electromagnet coil to drive the diaphragm to vibrate, and the frequency vibration is generated by the sounding board to produce sound. During the use of this kind of horn, if the horn is pressed and held for a long time, the contacts are prone to burning, which will affect the life of the horn. The main reason for burning is that when the electromagnet coil is connected to the circuit, the magnetic energy stored in the coil emits sparks on the contact surface at the moment the contact is disconnected. In order to overcome this problem, an electric horn with a non-contact structure has been developed on the market, and the phys...

AI Technical Summary

Problems solved by technology

However, it is difficult to adjust the sound of the speaker after the existing electric speaker drive circuit is packaged.

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