Abstract:
A fused speaker terminal cup for component attachment to a speaker enclosure and electrical connection to a speaker system is disclosed. In particular, the present invention provides a novel speaker terminal cup design in which a removable fuse is externally mounted therein for external access. In a preferred embodiment, the fuse receptacle is removable from the terminal cup to permit interchangeable fuse type selection.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    None. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to the technology of electrical connection design and, in particular, to the technology of a fused speaker terminal cup for component attachment to a speaker cabinet and electrical connection to a sound system. In particular, the present invention provides a novel speaker cup terminal device in which a fuse is externally mounted therein for external access without disassembly when used in cabinet speaker systems, such as aftermarket subwoofers for automobiles and home theaters. 
         [0004]    2. Description of the Related Art 
         [0005]    It is well known in the automotive, aftermarket audio, and home theater industries to provide speaker enclosures for special speakers designed for the production of low and very low frequency sound. Speaker drivers for low frequency sound are known as woofers. Speaker drivers for production of very low bass frequencies are known as subwoofers. Subwoofers reproduce sound between about 20 and 120 Hz. 
         [0006]    The reproduction of very low frequency sound requires significantly more electrical power than is required to reproduce high frequency sound. This is due to the large surface area of subwoofer speakers and the force required to move them. Amplifiers are provided for providing the required power. Depending on the application, the size and power of the amplifier will vary. 
         [0007]    To prevent damage to system components and to avoid the hazards of overheating electrical wiring, fuses are located in the wiring circuit. The fuses are typically positioned in a fuse receptacle between the electrical supply and the accessory. The main function of the fuse is to protect the wiring circuit and electrical accessory. The fuse contains an internal conductor which provides the electrical connection between the ends of the fuse. The conductor inside the fuse is a metallic strip that has a lower melting temperature than the wiring of the circuit. 
         [0008]    The size of the conductor is calibrated so that when the failure rating of the fuse is reached, sufficient heat will be generated to melt the conductor and break the circuit (burn the fuse). In use, if an accessory fails, the increased power demand in the circuit will exceed the failure rating of the fuse, causing the fuse to burn and separate, breaking the electrical connection. If a fuse is not used, overcurrent conditions could damage circuit elements or the electric accessory, overheat the wiring and perhaps cause a fire. The condition presents a danger to both life and property. 
         [0009]    Different fuse designs have different rating ranges. For example, AGU fuses (glass cylinder type) are commercially available with ratings between 5 and 60 amps. MAXI fuses (blade type) are commercially available with ratings between 20 and 80 amps. The more expensive ANL fuses (wafer type) are commercially available with ratings between 60 and 300 amps. For larger loads, circuit breakers are generally required. 
         [0010]    It is necessary for the sound system designer to provide compatible components throughout the system. For example, the amplifier must be capable of producing sufficient power to drive the speaker. The size of the speaker wire between the amplifier and speaker must be sufficient to safely carry the load generated by the amplifier. 
         [0011]    A fuse must be selected for protection of the wire. For example, with 14 awg wire, a maximum fuse size of 15 amps is recommended. With a wire gauge of 4 awg, a maximum fuse size of 125 amps is recommended. By matching the fuse to the wire size, overcurrent of the wire is prevented. 
         [0012]    Frequently, the load requirement of a desired speaker is very high. For example, many stereo amplifiers are rated at 2,000 or even 3,000 watts and 150 amp fuses are required for these units. Since the consumer may choose from a vast number of commercially available speakers, and match them with an amplifier, a fuse should be provided to protect the speaker driver as well. To protect their speakers, manufacturers locate fuses on the backs of the speakers which are rated below the amount of current which would damage the speaker driver. 
         [0013]    As with the other components of a sound system, speaker enclosures may be designed to accept several different speakers from different manufacturers. As a result, fuses are generally provided attached to the speaker itself, internally within the speaker enclosures. Alternative designs, in which the manufacturer places its own speakers in its own enclosures, such as with computer speakers, may have access to the fuse built into the back of the speaker enclosure. 
         [0014]    When speakers are assembled in customized enclosures, it is necessary to provide terminal connections between the outside of the speaker enclosure and the inside of the speaker enclosure. To resolve this problem, devices known as terminal cups are secured to an opening enclosure. Terminal connectors extend between the exterior and interior of the terminal cup. Speaker wire is connected between the speaker and the terminal connector on the interior side of the terminal cup. When the speaker enclosure is positioned as desired, speaker wiring from the amplifier is attached to the terminal connectors on the exterior side of the terminal cup to complete the electrical circuit. 
         [0015]    A principal disadvantage of the prior art designs is that they prohibit access to the speaker fuse without unscrewing the speaker and removing it from the enclosure. Another disadvantage of the prior art designs is that system designers and consumers may have fuse type preferences which cannot be exercised because speaker manufacturers install dedicated fuse receptacles at the time the speakers are manufactured. Therefore, there is a need to develop an improved fuse system with fuse type selectability and access provided from the outside of the speaker enclosure. 
       SUMMARY OF THE INVENTION 
       [0016]    Unique to this invention, a speaker terminal cup is disclosed having a fuse receptacle located within the speaker cup. A primary advantage of the preferred embodiment of the present invention is that it permits access to the fuse without disassembly of the cabinetry to which the terminal cup is attached. A second advantage of the present invention is that it permits exchangeability of fuse types as may be selected by the system designer or consumer. 
         [0017]    As referred to hereinabove, the “present invention” refers to one or more embodiments of the present invention which may or may not be claimed, and such references are not intended to limit the language of the claims, or to be used to construe the claims in a limiting manner. 
         [0018]    In the preferred embodiment of the present invention, a fused speaker enclosure terminal cup is disclosed. The terminal cup has an interior and an exterior. A pair of terminal connectors is attached to the base, and extend between the interior and exterior sides of the base. A fuse receptacle is located on the base. The fuse receptacle has a front side substantially aligned with the exterior side of the base, and a back side which extends to the interior side of the base. 
         [0019]    A pair of fuse connectors extends between the front and the back of the fuse receptacle. The front of the fuse receptacle is adapted to receive a removable fuse in electrical connection between the fuse connectors. One of the fuse connectors is electrically connected to one of the terminal connectors. 
         [0020]    In another preferred embodiment, the terminal cup has a recess located on the base, and the terminal connectors are attached in the recess. In another preferred embodiment, the base is dimensioned to cover a corresponding opening in the exterior of a speaker housing. In another preferred embodiment, the fuse receptacle is removably attached to the base of the terminal cup. In another preferred embodiment, the terminal connectors are removably attached in the recess of the terminal cup. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]    The objects and features of the invention will become more readily understood from the following detailed description and appended claims when read in conjunction with the accompanying drawings in which like numerals represent like elements. 
           [0022]    The drawings constitute a part of this specification and include exemplary embodiments to the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention. 
           [0023]      FIG. 1  is an isometric view of an assembled speaker having a fused terminal cup in accordance with a preferred embodiment of the present invention. 
           [0024]      FIG. 2  is an isometric view of the speaker assembly of  FIG. 1 , with the speaker removed. 
           [0025]      FIG. 3  is an isometric view of the exterior side of the fused terminal cup of  FIGS. 1 and 2 , illustrated as removed from the speaker enclosure. 
           [0026]      FIG. 4  is a view of the interior side of the fused terminal cup of  FIG. 3 . 
           [0027]      FIG. 5  is an isometric side view of the fused terminal cup of  FIGS. 3 and 4 . 
           [0028]      FIG. 6  is a top view of the fuse receptacle as removed from the fused terminal cup, and a coincident top view of the fuse shown removed from the fuse receptacle. 
           [0029]      FIG. 7  is an end view of the fuse receptacle as removed from the fused terminal cup. 
           [0030]      FIG. 8  is an isometric view of the interior side of the fused terminal cup of  FIGS. 1 ,  2 , and  3 , illustrating the electrical connection between one terminal connector and one fuse connector. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0031]    The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein. 
         [0032]      FIG. 1  is an isometric view of a speaker assembly  10 , in accordance with a preferred embodiment of the present invention. Speaker assembly  10  has a speaker  12  mounted in a speaker enclosure  14 . A fused terminal cup  20  is mounted on enclosure  14 . 
         [0033]      FIG. 2  is an isometric view of speaker assembly  10 , with the speaker  12  removed. In this view, it can be seen that enclosure  14  has an inside  16  and an outside  18 . 
         [0034]      FIG. 3  is a close-up isometric view of a preferred embodiment of fused terminal cup  20 . Fused terminal cup  20  has a base  22 . In this view, an exterior side  24  of terminal cup  20  is visible. As best seen in  FIG. 4 , terminal cup  20  has an opposite interior side  26 . Referring back to  FIG. 3 , in the preferred embodiment, holes  28  in base  22  are provided for receiving fasteners for attaching terminal cup  20  to outside  18  of speaker enclosure  14 . 
         [0035]    In the preferred embodiment, a recess  30  is formed on base  22  of terminal cup  20 . A pair of terminal connectors  40  is located in recess  30 . Terminal connectors  40  extend between exterior  24  and interior  26  of terminal cup  20 . In the preferred embodiment, terminal connectors  40  are comprised of a separate exterior portion, shown in  FIG. 3 , electrically connected to an internal portion, or terminal strip  42 , by terminal fasteners  44 , as shown in  FIG. 4 . 
         [0036]    A fuse receptacle  50  is located on base  22  of terminal cup  20 . In the preferred embodiment, fuse receptacle  50  is removably attached to terminal cup  20  to permit interchangeability with multiple fuse types, such as AGU, MAXI, ANL, or another type of fuse. A fuse  60  is shown inserted into fuse receptacle  50 . Fuse  60  as illustrated is a MAXI type fuse. 
         [0037]      FIG. 4  is a view of the interior side of fused terminal cup  20  of  FIG. 3 . In this view, fuse receptacle  50  is shown removed. A slot  32  is formed in base  22  of terminal cup  20 . In a preferred embodiment, fastener holes  34  are provided on base  22  for receiving fasteners  36  (see  FIG. 3 ) for securing fuse receptacle  50  to base  22 . 
         [0038]      37   FIG. 5  is an isometric side view of the preferred embodiment of fused terminal cup  20 , illustrating fuse receptacle  50  attached to base  22 . Fuse receptacle  50  is aligned with slot  32  to permit access to fuse  60  from the outside of speaker assembly  10 . 
         [0039]      FIG. 6  is a top view of fuse receptacle  50 , shown removed from fused terminal cup  20 . Fuse receptacle  50  has a body  52  and an opening  54  for receiving fuse  60 . A pair of fuse connectors  56  is located inside opening  54  of fuse receptacle  50  for electrical connection with fuse  60 . Fuse connectors  56  extend to the outside of body  52  for electrical connection to electrical wiring components (See  FIG. 8 ). Fuse  60  is shown removed from fuse receptacle  50 , and in alignment for insertion into fuse receptacle  50 . 
         [0040]      FIG. 7  is an end view of fuse receptacle  50 . Fuse connectors  56  are shown extending from body  52 . In a preferred embodiment, a pair of fastener receptacles  58  are attached to body  52  and are adapted to receive fasteners  36  (see  FIG. 3 ) to removably secure fuse receptacle  50  to base  22 . 
         [0041]      FIG. 8  is an isometric view of interior side  26  of fused terminal cup  20 . An electrical wire  70  is connected between one terminal strip  42  and one fuse connector  56 . An electrical wire  72  is connected between the other terminal strip  42  and speaker  12 . Another electrical wire  74  is connected between the other fuse connector  56  and speaker  12 . In this manner, fuse  60  is placed in the electrical circuit between terminal connectors  40  and speaker  12 . 
       OPERATION OF THE INVENTION 
       [0042]    The present invention discloses a novel speaker connection device. Unique to this invention, speaker assembly  10  includes fused terminal cup  20  having fuse receptacle  50  for receiving fuse  60  in a manner which permits access to fuse  60  from the outside of speaker assembly  10 . In the preferred embodiment, base  22  is dimensioned to cover a corresponding opening in speaker enclosure  14 . 
         [0043]    On terminal cup  20 , terminal connectors  40  extend from exterior  24  of base  22  to interior  26  of base  22 . In a preferred embodiment, terminal connectors  40  are comprised of a separate exterior portion that is electrically connected to an internal portion, or terminal strips  42 . In a preferred embodiment, terminal connectors  40  are connected to terminal strips  42  by terminal fasteners  44 . This configuration permits interchangeability of different types of terminal connectors  40  for attachment to terminal cup  20 . 
         [0044]    Terminal connectors  40  may be any type of connector suitable for securing speaker wires in electrical connection. Various types of connectors are commonly known and commercially available, such as RCA connectors, spring-clip or push-type, banana plug, and screw on. 
         [0045]    Fuse receptacle  50  is located on terminal cup  20 . Fuse receptacle  20  is adapted to receive removable fuse  60  in electrical connection with fuse connectors  56 . In the preferred embodiment, fuse receptacle  50  is removably attached to terminal cup  20 . This configuration permits interchangeability of different types of fuse receptacles  50  as compatible with the selected fuse  60  type for the application, such as AGU, MAXI, ANL, or another type of fuse. 
         [0046]    In a preferred embodiment, base  22  has fastener holes  34  for receiving fasteners  36  to secure fastener receptacle  58  to fuse receptacle  50 . Attaching fasteners  36  in this manner secures fuse receptacle  50  to base  22  of terminal cup  20 . Removal of fasteners  36  permits removal of fuse receptacle  50  for interchanging with a fuse receptacle  50  of a different type. When secured to base  22 , opening  54  of fuse receptacle  50  is aligned with slot  32  of base  22  to permit insertion of fuse  60 . 
         [0047]    One of fuse connectors  56  is electrically connectable to one of terminal connectors  40 . In this manner, fuse  60  is placed in the electrical circuit between terminal connectors  40  and speaker  12 . If the amplifier power to speaker  12  exceeds the rating of fuse  60 , fuse  60  will burn, resulting in disconnection of the electrical circuit and termination of electrical power supplied to speaker  12 . In this manner, the speaker and speaker components are protected. This can be a relatively frequent occurrence when custom subwoofer speaker assemblies are used. The unique benefit of this design is that fuse  60  can be removed and replaced without any need to disassemble speaker assembly  10 . Another benefit is that a single unit terminal cup  20  can be installed in a single opening in speaker enclosure  14 . 
         [0048]    In a preferred embodiment, terminal connectors  40  are located in a recess  30 . This configuration prevents interference of electrically connected terminal connectors  40  with other objects in the vicinity of outside  18  of speaker enclosure  14 . 
         [0049]    In another preferred embodiment, opening  54  of fuse receptacle  50  is aligned with slot  32  on base  22 . Body  52  extends to the interior side  26  of terminal cup  20 , on inside  16  of speaker enclosure  14 . This configuration prevents interference of electrically connected fuse connectors  56  with other objects in the vicinity of outside  18  of speaker enclosure  14 . 
         [0050]    Having thus described the present invention by reference to certain of its preferred embodiments, it is noted that the embodiments disclosed are illustrative rather than limiting in nature and that a wide range of variations, modifications, changes, and substitutions are contemplated in the foregoing disclosure and, in some instances, some features of the present invention may be employed without a corresponding use of the other features. Many such variations and modifications may be considered desirable by those skilled in the art based upon a review of the foregoing description of preferred embodiments. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention.