Prasad, S., Mansoori, J., and Park, J., "Performance Improvement of Automotive Acoustic Signal Devices using Electric PWM Control," SAE Technical Paper 2015-01-0235, 2015, doi:10.4271/2015-01-0235.
A vehicle horn is a sound-making device used to warn others of any approaching vehicle or of its presence. Some countries require horns by law. Conventional Horns are electromechanical with steel diaphragm and electromagnet acting upon it. Switching of horn is performed by mechanical contact breaker assembly that repeatedly interrupts the current to electromagnetic. Up-Down movement of diaphragm with response to the current creates a sound wave across horn.Conventional Horn faces the problem of wear and tear of mechanical contact and internal parts. Switching of contacts results in arcing. There is no current and surge voltage protection for the coil of conventional horn. These problems of conventional system might be accepted in the general market, but in specific markets which are using horn frequently; these have to be considered as serious issues. Especially, horns are one of the most abusive parts of vehicle in India. They are used very frequently due to the congested traffic conditions. It means that Indian market requires more reliable and robust horn than present horn system.This paper will simply show why conventional horn can't meet present requirements and new solution is necessary. Then, an electronic approach to drive the horn, electric horn has been described in the paper. This paper will show how to improve endurance cycle by using a microcontroller and semiconductor based switching.Lastly, this paper will describe the test results and performance data of electronic horn that show an increase of horn life and meet the requirements for India market.