Patent Publication Number: US-11051101-B1

Title: Vehicle subwoofer system and method of use

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     This invention relates to vehicle audio systems, and in particular to a vehicle subwoofer system and method of use. 
     Background of the Invention 
     Vehicle audio systems had their origins in the form of an AM radio installed in the instrument panel of a vehicle. Such radios were simple, monaural devices which typically incorporated a single speaker into the radio itself. 
     Since then, vehicle audio systems have evolved. Signal sources include AM and FM radios, satellite radios, CD players, tape players of various kinds, digital recorders, and even local wireless transmissions from a variety of digital players to the unit mounted in the vehicle instrument panel. 
     Similarly, the quality and frequency response of sound reinforcement incorporated into vehicle audio systems has increased dramatically. Today&#39;s vehicle audio systems are capable of producing multi-channel sound reproduction and reinforcement such as stereo, quadraphonic, and a wide variety of multi-speaker stage environments. The speakers themselves have improved response band frequencies as well as power-handling capabilities from the amplifiers in the vehicle audio system. 
     Currently available speakers typically include two or three separate speakers in each speaker assembly, in order to more accurately project high, mid, and low frequency sound. Such speaker assemblies are referred to as two-way and three-way speakers. 
     Extreme low frequencies require relatively large speakers to project the long wavelengths associated with low frequency sound waves, such as the bass part in a musical composition. Specialized low-frequency speakers called subwoofers are used for this function. They are large, dedicated speakers, which typically require their own amplifier powerful enough to drive the subwoofer. 
     Because of their size requirements, subwoofers are typically not installed at the factory, but are rather an aftermarket installation for vehicles such as passenger cars, pickup trucks, vans, etc. A sedan subwoofer installation, for example, would usually place the subwoofer enclosure in the trunk of the car, because that is generally the only space large enough to accommodate the dimensions of the subwoofer enclosure. 
     Currently available aftermarket subwoofer installations involve a great deal of labor, in that wiring must be installed from the audio control unit mounted in the vehicle instrument panel, back through the body of the vehicle, to the trunk. Then electrical power must be wired into the subwoofer amplifier from the [typically] 12 volt vehicle electrical system. Thus, conventional subwoofer installations involve a significant installation labor cost above and beyond the cost of subwoofer/amplifier package itself. Therefore, it would be desirable to provide an easily-installed subwoofer package which substantially reduces the labor component of the installation cost. 
     Existing Designs. 
     A number of applications have been made, and patents issued, for vehicle audio systems incorporating subwoofers. For example, patent applications with publication numbers 2009/0190773 and 2003/0103634 were made by Katayama et al. and Ito respectively, and U.S. Pat. No. 8,068,617 was issued to Katayama et al., for permanently installed vehicle audio systems. These suffered from the disadvantages referred to above, that is, labor-intensive and time-consuming, and therefore expensive, installation. 
     A number of subwoofer kits are commercially available. These include a subwoofer speaker, an amplifier, twenty or thirty feet of speaker wire, and electrical power wire. The installer is required to thread speaker wire through the vehicle frame from the front instrument panel to the rear of the vehicle, and then wire the subwoofer amplifier into the vehicle electrical system. These subwoofer kits suffered from the afore-mentioned disadvantages, specifically, labor-intensive and time-consuming, and therefore expensive, installation. 
     Thus, it would be desirable to provide a vehicle subwoofer system and method of use which is quick and easy to install, which does not require installation of speaker wire through most of the length of a vehicle frame, and which does not require wiring the amplifier of the subwoofer into the vehicle electrical system in order to power the amplifier. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide a vehicle subwoofer system and method of use whose installation does not require installing speaker wire through the vehicle frame from the front instrument panel to the rear of the vehicle. Design features allowing this object to be accomplished include a powered woofer connected to a vehicle DC power receptacle through an inverter, and to a speaker by input wires. Advantages associated with the accomplishment of this object include reduced subwoofer system installation time, and associated installation cost savings. 
     It is another object of the present invention to provide a vehicle subwoofer system and method of use whose installation does not require permanently wiring the subwoofer amplifier into the vehicle electrical system. Design features allowing this object to be accomplished include a powered woofer connected to a vehicle DC power receptacle through an inverter. Advantages associated with the accomplishment of this object include reduced subwoofer system installation time, and associated installation cost savings. 
     It is still another object of this invention to provide a subwoofer system and method of use which is simple to install, and whose installation requires no specialized knowledge or skills Design features enabling the accomplishment of this object include a powered subwoofer connected to a vehicle DC power receptacle through an inverter using the inverter&#39;s DC power line and DC power plug, and to a speaker by input wires terminating in quick-attach clips such alligator clips. Advantages associated with the realization of this object include quick and easy installation, and the associated installation cost savings. 
     It is yet another object of this invention to provide a subwoofer system and method of use which is inexpensive. Design features allowing this object to be achieved include the use of commercially available components, and components made of readily available materials. Benefits associated with reaching this objective include reduced cost, and hence increased availability. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention, together with the other objects, features, aspects and advantages thereof will be more clearly understood from the following in conjunction with the accompanying drawings. 
       Three sheets of drawings are provided. Sheet one contains  FIG. 1 . Sheet two contains  FIG. 2 . Sheet three contains  FIG. 3 . 
         FIG. 1  is a schematic view of a vehicle subwoofer system. 
         FIG. 2  is a top view of a vehicle subwoofer system installed in a vehicle trunk. 
         FIG. 3  is a top view of an exemplary embodiment of an input wire assembly. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIG. 1  is a schematic view of vehicle subwoofer system  2 . As may be observed in this figure, vehicle subwoofer system  2  is made up of powered subwoofer  4  electrically connected to a vehicle DC power source  22  through inverter  16 , and to speaker  12  by means of input line assembly  28 . In general, throughout this disclosure, “DC” refers to direct current, and “AC” refers to alternating current. Powered subwoofer  4  incorporates subwoofer audio input  5  and AC power line  14 . 
     Speaker  12  is part of an existing vehicle audio system, whose speaker contacts  11  may extend into the trunk of a vehicle into which the instant subwoofer system is to be installed, and thus speaker contacts  11  may be readily available to which to attach alligators clips  10 . 
       FIG. 3  is a top view of an exemplary embodiment of input wire assembly  28 . 
     Although it is intended to fall within the scope of this disclosure that any appropriate type of input wire assembly  28  be used, the embodiment of input wire assembly  28  illustrated in  FIG. 3  includes a positive input wire  6  and a negative input wire  8  extending from an alligator clip  10  at one end of each, to an audio plug  30  at their opposite end. 
     Audio plug  30  may be a phono jack, an RCA plug, or any other appropriate audio plug to connect to subwoofer audio input  5 . Where powered subwoofer  4  incorporates wire conductor clamps in its audio input  5 , input wire assembly  28  may dispense with audio plug  30 , and merely incorporate an appropriate length of positive input wire  6  and negative input wire  28  at ends opposite alligator clips  10 , unsheathed for clamping at their ends opposite alligator clips  10 . 
       FIG. 2  is a top view of vehicle subwoofer system  2  installed in a vehicle trunk  26 . Many currently available vehicles incorporate a DC power source  22  in their trunks  26 . Inverter  16  may be plugged into such DC power source  22  using the inverter&#39;s DC power line  18  terminating in the inverter&#39;s DC power plug  20 . In the preferred embodiment, inverter  16  was a commercially available 12 volt DC to 110 volt AC inverter, e.g. in the 350 watt power range. 
     The powered subwoofer  4  power line  14  terminates in AC plug  15 , which may be quickly and easily plugged into an inverter AC receptacle  17 . In this manner, powered subwoofer  4  is quickly and easily connected to the vehicle&#39;s DC power source  22  using the inverter&#39;s DC power plug  20 , and the powered subwoofer&#39;s AC plug  15  plugged into an inverter AC receptacle  17 . DC power source  22  may be a DC power receptacle, which are increasingly being built into vehicles  24  for the convenience of the vehicle  24  users. 
     While the above description describes a subwoofer system  2  installed in a vehicle trunk  26 , attached to the speaker contacts  11  of a rear speaker  12 , it is intended to fall within the scope of this disclosure that the instant subwoofer system  2  be installed in any location on a vehicle, connected to any available speaker contacts  11  of a vehicle speaker  12 . 
     Accordingly, the instant method of use for a vehicle subwoofer system comprises the steps of: A. Providing a vehicle having a speaker with speaker contacts  11  and a DC power source  22 , an input line assembly having a first end and a second end, a powered subwoofer  4  having audio input  5  and AC power line  14 , and an inverter  16  having an inverter AC receptacle  17  and DC power line  18 ; B. Electrically connecting a first end of the input line assembly  28  to the speaker contacts  11 ; C. Electrically connecting a second end of the input line assembly  28  to the powered subwoofer audio input  5 ; D. Electrically connecting the powered subwoofer AC power line  14  to the inverter AC receptacle  17 ; and E. Electrically connecting the inverter DC power line  18  to the vehicle DC power source  22 . 
     The instant method of use for a subwoofer system may include the further steps of: F. Providing an input line assembly having a positive input wire  6  and a negative input wire  8 , an alligator clip  10  electrically attached to a first end of the positive input wire  6 , and an alligator clip  10  electrically attached to a first end of the negative input wire  8 ; G. Electrically connecting the positive input wire  6  to a speaker contact  11  by clipping its alligator clip  10  to one of the speaker contact  11 ; and H. Electrically connecting the negative input wire  8  to a speaker contact  11  by clipping its alligator clip  10  to one of the speaker contact  11 . 
     The instant method of use for a subwoofer system may include the further steps of providing an audio plug  30 , electrically connecting a second end of the positive input wire  6  to the audio plug  30 , electrically connecting a second end of the negative input wire  8  to the audio plug  30 , and plugging the audio plug  30  into the subwoofer audio input. 
     The instant method of use for a subwoofer system may include the further steps of providing a DC power source  22  which is a DC power receptacle in the vehicle, and a DC power plug  20  electrically connected to an end of the inverter DC power line  18  opposite the inverter  16 ; and electrically connecting the DC power line  18  to the DC power source  22  by plugging the DC power plug  20  into the DC power receptacle. 
     The instant method of use for a subwoofer system may include the further steps of providing an AC plug  15  electrically connected to an end of the AC power line  14  opposite the powered subwoofer  4 , and an inverter AC receptacle  17  on the inverter  16 ; and electrically connecting the AC power line  14  to the inverter  16  by plugging the AC plug  15  into the inverter AC receptacle  17 . 
     Following the above method steps, when an audio signal such as a musical audio signal is played through speaker  12 , such audio signal is transmitted through input line assembly  28  to powered subwoofer  4  and amplified, with powerful bass sound re-enforcement. Thus, a listener may listen to the sound signal amplified by powered subwoofer  4  derived from speaker  12  through speaker contacts  11 . 
     In the figures, powered subwoofer  4  is illustrated as being electrically connected to a single speaker  12  through input line assembly  28 . This arrangement is generally sufficient to produce a pleasing bass sound reinforcement through powered subwoofer  4 . Stereo vehicle sound systems typically have two rear speakers  12 , each emitting a channel, e.g. left and right channels. Powered subwoofer  4  may be connected to either speaker  12  as described above. 
     If additional bass sound reinforcement depth and range is desired, one vehicle subwoofer system  2  may be electrically connected to one speaker  12 , and another vehicle subwoofer system  2  may be electrically connected to another speaker  12 , as described above. 
     In the preferred embodiment, powered subwoofer  4  was a commercially available powered subwoofer with AC power line  14  and audio inputs  5 , such as a 100 watt peak power self-contained powered subwoofer designed to be powered by 110 volts alternating current (AC). Inverter  16  was a commercially available self-contained inverter with built-in DC power line  18  and inverter AC receptacles  17 , such as a 350 watt inverter. Alligator clips  11 , positive input wire  6 , negative input wire  8 , and audio plug  30  were commercially available items. Vehicle  24  having speaker(s)  12  with speaker contacts  11 , and trunk  26 , was as existing vehicle such as is commonly available on the market. 
     While a preferred embodiment of the invention has been illustrated herein, it is to be understood that changes and variations may be made by those skilled in the art without departing from the spirit of the appending claims. 
     DRAWING ITEM INDEX 
     
         
           2  subwoofer system 
           4  powered subwoofer 
           5  audio input 
           6  positive input wire 
           8  negative input wire 
           10  alligator clip 
           11  speaker contact 
           12  speaker 
           14  AC power line 
           15  AC plug 
           16  inverter 
           17  inverter AC receptacle 
           18  DC power line 
           20  DC power plug 
           22  DC power receptacle 
           24  vehicle 
           26  trunk 
           28  input line assembly 
           30  audio plug