.jpg)
Ahorn is a sound-making device installed onmotor vehicles,trains,boats, and other types of vehicles. The sound it makes usually resembles a “honk” (older vehicles) or a “beep” (modern vehicles). The driver uses the horn to warn others of the vehicle's presence or approach, or to call attention to some hazard. Motor vehicles, ships and trains are required by law in some countries to have horns.Trams,trollies,streetcars, and evenbicycles are also legally required to have an audible warning device in many areas.
 | This sectionneeds additional citations forverification. Please helpimprove this article byadding citations to reliable sources in this section. Unsourced material may be challenged and removed.(January 2011) (Learn how and when to remove this message) |
Modern car horns are usually electric, driven by a flat circular steeldiaphragm that has anelectromagnet acting on it in one direction and a spring pulling in the opposite direction. The diaphragm is attached tocontact points that repeatedly interrupt the current to that electromagnet causing the diaphragm to spring back the other way, which completes the circuit again. This arrangement opens and closes the circuit hundreds of times per second, which creates a loud noise like abuzzer orelectric bell, which sound enters a horn to be amplified.
A traditional style automobile horn includes an expansion chamber cast into its body, once spiral shaped, to better match the acoustical impedance of the diaphragm with open air, and thus more effectively transfer the sound energy. Sound levels of typical car horns are approximately 107–109decibels, and they typically draw 5–6amperes of current.
Horns can be used singly, but are often arranged in pairs to produce aninterval consisting of two notes, sounded together; although this doubles the sound volume, the use of two differing frequencies is moreperceptible to the human ear than two horns of the same frequency, particularly in an environment with a highambient noise level. Typical frequencies of a pair of horns of this design are 500 Hz and 405–420 Hz (approximately B4 and G♯4,minor third).
Most cars,motorcycles, andmotor scooters have for some time used a cheaper and smaller alternative design, which, despite retaining the name "horn," abandons the actual horn ducting and instead relies on a larger flat diaphragm to reach the requiredsound level. Sound levels of such horns are approximately 109–112 decibels, and they typically draw 2.5–5 amperes of current. Again, these horns can be either single, or arranged in pairs; typical frequencies for a pair are 420–440 Hz and 340–370 Hz (approximately G♯4–A4 and F4–F♯4) for this design.
A horn grille is a part of some designs ofcar or other motor vehicle that has an electric horn, such as amotor scooter.
Larger, louderair horns, as found ontrucks (lorries) andbuses, are driven byair compressors, or supplied by reservoirs charged to operate theirair brakes. The compressor forces air past a diaphragm in the horn's throat, causing it to vibrate. Usually two are used, with varied frequencies generally lower than those of automobile horns, in the 125–180 Hz (approximately C3–G3) range. Sound levels are approximately 117–118 decibels.
In order to be heard at the longer distances that trains require to warn of danger or stop, theirlocomotives have pneumatictrain hornsthat are both louder and lower in frequency than motor vehicle horns. Operated by compressed air from the train'sair brake system, their sound level is 146–175 dB. In theUnited States, train horns are required to have a minimum sound level of 96 dB and a maximum sound level of 110 dB at 100 ft (30 m) in front of the train.
To distinguish their sound from truck and bus air horns, train horns in the U.S. consist of groups of two to five horns (called "chimes") which have different notes, sounded together to form achord.
InJapan, most modern trains like209 series orE233 series from the first half of the 1990s onwards use electric horns as primary in passenger use. Although electric horns were used bySeibu 2000 series, air horns were primarily used until the 1990s. Modern Japanese trains may still be equipped with both air horns and electric horns.
Most modern streetcars, trams and trolley cars including low-floor vehicles around the world also employ horns or whistles as a secondary auditory warning signal in addition to thegong/bell which either use the sound of air horns or electric automobile car horns.
Ships signal to each other and to the shore withair horns, sometimes called whistles, that are driven with compressed air or from steam tapped from the power plant. Low frequencies are used, because they travel further than high frequencies; horns from ships have been heard as far as fifteen kilometres (ten miles).[1] Traditionally, the lower the frequency, the larger the ship. TheRMSQueen Mary, anocean liner launched in 1934, had three horns based on 55 Hz (corresponding to A1 ), a frequency chosen because it was low enough that the very loud sound of it would not be painful to the passengers.[2] ModernInternational Maritime Organization regulations specify that ships' horn frequencies be in the range 70–200 Hz (corresponding to C♯2-G3) for vessels that are over 200 m (660 ft) in length. For vessels between 200 and 75 m (660 and 250 ft) the range is 130–350 Hz and for vessels under 75 m (250 ft) it is 70–700 Hz.[3]
Smaller craft typically use electric diaphragm horns.
Portableair horns driven by canned compressed air are also used, as well as for officiating sports events and recreational activities.
.jpg)
Aklaxon is a type of an electromechanical horn or alerting device. Mainly used oncars,trains andships, it produces an easily identifiable sound, often transcribedonomatopoeically in English as "awooga". Like most mechanical horns, it has largely been replaced by solid-state electronic alarms, though the memorable tone has persisted.Klaxon wasoriginally a brand name.[4]
The klaxon horn's characteristic sound is produced by a spring-steel diaphragm with a rivet in the center that is repeatedly struck by the teeth of a rotating cogwheel. The diaphragm is attached to ahorn that acts as an acoustic transformer and controls the direction of the sound.[5]
In the first klaxons, the wheel was driven either by hand or by an electric motor. American inventorMiller Reese Hutchison (later chief engineer ofThomas Edison) patented the mechanism in 1908.[6]The Lovell-McConnell Manufacturing Company ofNewark, New Jersey bought the rights to the device and it became standard equipment onGeneral Motors cars.[7] Franklyn Hallett Lovell Jr., the founder, coined the nameklaxon from theAncient Greek verbklazō, "I shriek".[8]
Klaxons were first fitted to automobiles andbicycles in 1908. They were originally powered by six-voltdry cells, and from 1911 byrechargeable batteries. Later hand-powered versions were used as military evacuation alarms and factory sirens. They were also used assubmarine dive and surface alarms beginning in theSecond World War.
The English company Klaxon Signals Ltd. has been based inOldham,England for the last 80 years,[when?] with premises also inBirmingham. The French Klaxon company was acquired by the ItalianFiamm Group in the 1990s. In 2005 Klaxon Signals sold the rights for the hooter or klaxon range to Moflash Signalling Ltd., based in the original Klaxon Factory in Birmingham, England.[citation needed]
The Moflash Company discontinued the Klaxet hooter in 2013, but continued to produce the A1 hooter, the only original Klaxon left in production.
Several languages have either borrowed or transcribed the name into their lexicons. In Japanese, the word "klaxon" (クラクション,kurakushon)refers to car horns in general. This is also true in languages such as French (klaxon), Italian (clacson), Greek (κλάξον), Dutch (claxon), Russian (клаксон), Polish (klakson), Spanish (claxon), Romanian (claxon), Bulgarian (клаксон), Czech (klakson), Turkish (klakson), Indonesian (klakson), some Arabic dialects (كلاكسون) and Korean (클랙슨).
.jpg)
In countries applying theVienna Convention on Road Traffic, usage of audible warnings is limited, and allowed only in two cases:[9]
Various types of vehicle horns are used bypercussionists assound effects, or even melodically, in musical works.[10] For example,George Gershwin's 1928 orchestral workAn American in Paris calls for the use of 4 taxi horns.[11]György Ligeti's operaLe Grand Macabre features two "Car Horn Preludes" scored for 12 bulb horns, each one tuned to a specific pitch.[12]
Thehornophone consists of a set of bulb horns tuned to achromatic scale and arranged as amusical keyboard on a frame like axylophone. Theklaxophone is a similar musical instrument using a set of klaxons.
The songCar Alarm byToo Many Zooz is based on the sound of a honking horn.[13]
Part of a series of articles oncars | |||||||||||||
| Body |
| ||||||||||||
Exterior equipment |
| ||||||||||||
Authority control databases: National |
|---|
