Abstract:
One embodiment is a warning system for bicycles that sounds like a car horn and weighs less than a pound. The batteries are size AAA.

Description:
RELATED APPLICATION 
     This application claims the benefit of provisional patent Application No. 61/386,562 received Sep. 16, 2010. 
     FIELD 
     This application relates to a bicycle signaling device that uses light-weight batteries to generate the sound of a car horn. 
     PRIOR ART 
     This invention enables a bicycle rider for the first time to use a car horn powered by batteries no bigger than size AAA. 
     Prior art teaches away from this. For decades it has taught that any car horn requires batteries that are too heavy to be practical on a bicycle. 
     This is a new combination of the light-weight batteries and a car horn. It brings the unexpected and substantial benefits of working, working well and providing the first effective signaling device for biking in modern-day traffic. 
     From the time motor vehicles first joined bicycles on roads, cyclists have used various signaling devices to alert motorists. Motorists likewise needed to alert other motorists. 
     Warning motorists became increasingly difficult as drivers became more insulated by steel, glass, air conditioning and electronic distractions. For motor vehicles, a gasoline engine generating current to recharge a massive battery enabled ever-more effective electronic signaling devices, leading to the present car horn. (For example, see a 1910 car horn patent titled “Electric Signaling Device for Motor-cars. Cite No. 1.) 
     For bicycles, it was impractical to add a heavy car battery, so cyclists could not use the warning technology that motorists found most effective. 
     Prior art teaches that car horns require more current than small batteries can produce. They typical draw 5-6 amperes, with smaller ones drawing 2.5-5. (For example, see Wikipedia, Non-patent Cite No. 1.) Prior art also includes horns that use less than 1.5 amps and have been on the market for well over a decade. (See advertisement for horn in preferred embodiment online in 1997, Non-patent Cite No. 2.) 
     For batteries, prior art teaches that car horns can be powered by lead-acid batteries which are too heavy to be acceptable for use on bicycles. Prior art does include small batteries. The current produced by a small AAA alkaline battery is often stated as 1200 mAh. (For example, see Wikipedia, Non-patent Cite No. 3.) Prior art teaches that under a high load such as a car horn this can be reduced to an effective capacity of less than one-quarter of that. (For example, see Wikipedia and Radio Shack&#39;s On-line Battery Guidebook, Non-patent Cites No. 4, 5.) No one expected that these small batteries could power a car horn. 
     Cyclists have pooled their knowledge about this online for years without finding this solution. Typical is a topic last month on a bike forum: “I want a loud car horn on my bike.” The only responsive answer was, “If you want to lug around a 7 lb battery, there are some compact 12 v horns that are extremely loud. (Non-patent Cite No. 6.) 
     For decades people have tried without success to make car horns work with various small batteries. Typical is an engineer working for Instructables.com who shows online the steps for, “Putting A Car Horn On Your Bicycle!” Initially it is powered by AA batteries, which are larger than the AAA batteries in the preferred embodiment. Seven months later he futilely asks for suggestions for batteries that would actually work. “An easy fix is using a lead acid but they are so heavy!” Other people tell him about other failures, such as, “I tried 8 size D batteries and all I got was a click. Also tried . . . 9-V . . . same thing.” (Non-patent Cite No. 7. Similar: Non-patent Cites No. 10-15) 
     There are videos online showing how to put a car horn on a bike, but all appear to have been powered by heavy lead-acid batteries. The apparently most-watched video uses a 12 volt rechargeable drill battery. (Non-patent Cite No. 8. Similar: Non-patent Cites No. 16-48.) 
     Electric car horns were invented over a hundred years ago. (Cite No. 1.) Small AAA-size alkaline batteries were invented over fifty years ago. (Cite No. 2.) The horn model in the preferred embodiment has been on the market and on the web for more than 14 years. (Non-patent Cite No. 2.) During all those years, people failed to successfully combine these batteries and horns. 
     The prior art teaches away from combining these known elements. The results of combining these small batteries with this car horn were totally unexpected. Not only did the horn blare loudly, it could do so repeatedly. 
     This invention meets the long-felt but unsolved need for a bicycle device powered by small batteries that sounds like a car horn. 
     The car horn has a unique benefit to cyclists: Its distinctive sound is immediately recognized by most drivers as a top-priority warning of an imminent two-car crash. Drivers react to car horns more urgently than any other sound. 
     Also essential, a car horn is loud enough to penetrate motor vehicles and alert distracted motorists. None of the typical bicycle signaling devices—from bells to small squeeze horns to buzzers—can do this. Some are counterproductive, signaling the motorist that it is merely a small bicycle, not an oncoming motor vehicle. 
     (The few bicycle devices that are extremely loud, such as some whistles, large bulb squeeze horns and compressed-gas powered horns, have other major offsetting disadvantages. Examples: whistles are often illegal because police use them; horns louder than car horns damage hearing; squeeze horns take a hand away from steering and braking.) 
     The characteristics of a bicycle and cyclist are quite different from those of a motor vehicle and driver, requiring a quite different signaling device. 
     For the bicycle, to be effective and practical for biking in traffic a signaling device must meet all these criteria:
         It sounds like a car horn;   It is not heavy;   Any batteries:
           can produce many honks;   work in cold and rain;   hold their charge when not used;   can typically be bought nearby;   
           It is very loud, but not damaging to hearing;   It is small.       

     This invention is the first to meet all these minimum requirements. 
     Prior art bicycle electronic signaling devices and horns produce sounds ranging from an unobtrusive pleasant sound to an attention-getting pulsating signal to a siren. (Cites No. 3, 4; Non-patent Cite No. 9.) None generate the sound of a car horn. 
     This invention empowers cyclists. Instead of feeling and being vulnerable when they see a car or truck about to turn into their path, they can move their thumb and blow a loud car horn to immediately get the full attention of the distracted driver. Cycling in traffic becomes safer and more comfortable. 
     SUMMARY OF THE INVENTION 
     My invention is a warning system on bicycles that sounds like a car horn, is about as loud as a car horn and can weigh less than a pound, with batteries. 
     The batteries are no bigger than size AAA. They produce many honks, work in cold and rain, store well, need no charging and can be bought almost everywhere. 
     It uses a car horn which has been sold for many years solely for motor vehicles. 
     The numbers of honks the batteries generate can be greatly increased by attaching the horn to a metal bracket which has a structure that reduces the electrical current needed to produce the sound. 
     This is done by tuning the resonance frequency of the bracket to the vibrating frequency of the horn. The structural characteristics of the bracket, such as thickness, length, springiness and number of bends, have been modified so that its vibrations are synchronized with the horn. 
    
    
     
       DRAWINGS 
       Figures 
         FIG. 1  Bicycle, switch, wire, horn, battery container 
         FIG. 2  Side view: horn, bracket, battery container, clamp, battery holder, batteries, lid 
         FIG. 3  Battery, battery holder 
         FIG. 4  Rear view: battery container, lid, horn 
         FIG. 5  Switch 
         FIG. 6  Side view: bracket 
     
    
    
     REFERENCE NUMBERS 
     
         
         
           
               2  horn 
               4  mount 
               6  battery container 
               8  switch 
               10  wire connecting batteries and switch 
               12  clamp 
               14  lid 
               16  battery holder 
               18  battery 
               50  bicycle 
           
         
       
    
     DESCRIPTION OF PREFERRED EMBODIMENT 
     Structure 
     The relationship between all the components of one embodiment of the device is illustrated by  FIG. 1 . The switch [ 8 ] and battery container [ 6 ] are attached to the bicycle [ 50 ] by clamps. 
     The switch is on the handlebars positioned so that it can be pushed by a thumb or finger at the same time the cyclist is steering the bike and applying any handbrakes. This enables the cyclist to take evasive action in an emergency without waiting to see if the oncoming motorist changes course in time. 
     The battery container is attached to the bike&#39;s top tube, positioned so that the attached horn [ 2 ] is pointed forward to best project sound toward oncoming traffic. The horn is at least 2.5 feet from the cyclist&#39;s ears to minimize potential hearing loss from the horn blasts. The horn is as loud as possible without exceeding the prudent safety limit of 110 decibels. 
       FIG. 2  shows a side view of the sound and battery components. They are firmly attached to the bicycle frame by a stainless steel hose clamp [ 12 ] around the battery container [ 6 ]. 
     Within that container is the battery holder [ 16 ] positioning eight batteries [ 18 ]. The holder is shown partially extended, with the lid [ 14 ] separated. 
     The horn [ 2 ] is a 12 volt car disc horn, such as the Wolo Manufacturing Corp.&#39;s Model 260-2T MidRange Black Finish, advertised as drawing less than 1.5 amps. and having a pitch of 480 HZ. (Non-patent Cite No. 49, 50.) 
     The horn is attached to the battery container by a metal bracket that is about 4 inches long and about ⅞ of an inch wide. It is curved as shown in  FIG. 6 . Its thickness and springiness have been selected so that its resonance frequency matches the vibrating frequency of the horn. 
       FIG. 3  shows one of the eight size AAA alkaline manganese dioxide batteries [ 18 ]. Each battery produces about 1.5 volts when fresh and weighs about 0.38 ounces. Its capacity is often stated as 1200 mAh, but its effective capacity with a car horn is much lower. 
     They are held in the battery holder [ 16 ]. This holds eight batteries and wires them in series to snap connectors. This is Eagle Plastic Devices&#39; part #12BH483B-GR. That connector snaps to a two-strand 18 gauge insulated wire [ FIGS. 4 ,  5 :  10 ] which runs to the switch [ FIG. 5 :  8 ]. 
     That switch is a durable momentary, normally-open pushbutton. 
     Alternative Embodiments 
     The claims cover many embodiments, including the following examples.
     Different small, light, disposable battery types.   Different horns.   More than one pushbutton mounted on the handlebar so that they can be reached more easily from different hand positions.   Various designs of pushbuttons so that they can be more visible or pushed with different fingers or while simultaneously using handbrakes and/or steering.   Mounting the horn and battery container separately on the bicycle.   Mounting the horn and/or battery container in other places, including the seat, handlebars, at the front of the bike or in a cargo box.   

     Ramifications 
     Biking in traffic is scary and dangerous. Bikes are narrow and hard to see. Motor vehicle drivers focus on approaching cars and truck, constantly choosing lanes and routes. They are often distracted and can&#39;t hear oncoming bicycles. 
     This invention finally gives cyclists the same audio warning capability that has proved most successful on motor vehicles. 
     Since many people would like to bike on roads but are primarily deterred by the scary traffic, this will make more people feel comfortable biking in traffic. 
     Besides reducing bicycle crashes and increasing goodwill between cyclists and motorists, this will help more people to cycle more often in their neighborhood and beyond—improving their spirits and health, while saving them money and reducing global climate change, air pollution, traffic congestion, oil consumption and parking problems.