This came up during our weekly Friday lunch at the pub.
How do car horns work? You need electrical for them to work (dead battery = no horn).
I’m pretty sure they use air, but where does it come from? They don’t have reservoirs, or do they?
Thanks MtM
Depends on the type of horn. Many tractor-trailer rigs use air horns, which are quite loud, but most car horns are simply speakers attached to a tone generator if I’m not mistaken.
Agree–to amplify, I once installed air horns on my car. It is a horn that uses forced air, and includes an air compressor to force the air. I don’t know how the actual tone is produced, though. Regular car horns don’t require any forced air.
So there’s no practical technical reason why the trucks and SUVs get the aggressive BLAT and the little passenger cars are stuck with a squirrel and its kazoo?
A friend of mine got a horn that played the opening to Dixie, like the General Lee had in Dukes of Hazard. It had a compressor that forced air through 5 or 6 different horns (that looked just like the kind with a rubber bulb on the end that you might put on your bike), and each horn played a different note. Some little mechanism in there directed the air from the compressor to each horn in the note succession of the song. Worked pretty well for a while, but then one or two of the horns crapped out and it just played the other ones: “Honk! _____ honk honk _____ honk honk honk ____ _____ honk.”
Big car gets big sound.
It’s pretty funny to hear a car alarm going off that’s just about drained the battery. Tho’ not funny enough to make up for four hours of the thing going off in the first place.
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None at all. I’ve seen electric car horn kits that will do the big semi-truck air-horn TOOOOOOT; you can hook one of those to a little ol’ hatchback and surprise folks on your commute, if you’re inclined.
Just thought I’d add my 2¢ about a special type of car horn - the AHH - OOO - GAHH horn !!! I took one apart and found that it is driven by an electric motor. On the motor shaft is a disk with a few bumps on it. This in turn spins underneath a fixed membrane that has MANY bumps in it. Result? A very raucous mechanical grinding that sounds like … well I’m sure you’ve all heard it.
Dunno. I put an air horn on my motorcycle once but the electrical system couldn’t deliver enough amps to power it unless I was going at least 50. At low speeds I could tell that the compressor was spinning but no sound. Similar might be true of very small cars with underpowered alternators.
Fiat Spyders of the 70’s used two air horns with an electric compressor. They worked great. I suspect the one that didn’t work well on the motorcycle was a poor design, or perhaps designed to be used with an automobile battery rather than a motorcycle battery.
Imagine a diaphragm with and electromagnet pointed at its face. A switch is carefully arranged such that when the diapragm moves toward the magnet, the switch opens, turning off the electromagnet. The diaphragm, not longer attracted by the magnet, relaxes and drops away from the magnet, closing the switch and re-energizing the magnet. Repeat as necessary.
Easy, eh?