Abstract:
A battery powered wireless audio speaker comprising a passive radiator is disclosed. The perimeter portion of the passive radiator is sandwiched between the speaker chassis and the retention gasket that resides between an external overlying perforated cover to firmly secure the passive radiator. The construction is capable of being well suited to enhance and improve integrity to the seal between the passive radiator and the speaker chassis in strenuous environment conditions such as when a speaker is submerged in water.

Description:
INCORPORATION BY REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims benefit under 35 U.S.C. §119(e) from U.S. Provisional Application No. 61/887,876, filed on Oct. 7, 2013, the disclosure of which is incorporated herein by reference in its entirety. 
     
    
     FIELD 
       [0002]    This patent application generally relates to audio speakers, and more specifically to audio speakers having one or more passive radiators. 
       BACKGROUND INFORMATION 
       [0003]    Conventional speakers are generally comprised of an internal compartment defined by a chassis or from having one or more main drivers (“active driver”) mounted thereon. Often electronic circuitry that controls the speaker is contained within the internal compartment. Some speakers also employ a passive radiator (or a drone cone) that is also mounted on the chassis. The passive radiator is typically the same or similar to the main driver, but without a voice coil and magnet assembly. When the main driver and the passive radiator are both mounted to a sealed speaker compartment, the movement of the main driver fluctuates the internal air pressure within the compartment resulting in the passive radiator to fluctuate with sound. 
         [0004]    In order to have a consistent and desired tune, the passive radiator needs to be properly mounted to the chassis in a manner that maintains the integrity of the compartment seal so that the pressure differential required to fluctuate the passive radiator in the desired manner is maintained. In conventional manufacturing constructions, the outer perimeter portion of the passive radiator is efficiently mounted to the speaker chassis with an adhesive. The adhesive secures the inner side of the perimeter portion of the passive radiator to an underlying corresponding perimeter support structure on the chassis. A sealed internal compartment is thus formed between the chassis and the passive radiator. The seal internal compartment serves the dual purpose of protecting the external electronics from exposure to the environment while also allowing the active driver to fluctuate the air pressure within the internal compartment to energize the passive radiator. 
         [0005]    These days wireless speakers, often battery powered such as those marketed by applicant under the BRAVEN brand, are common. Such speakers are being used more and more in various indoor and outdoor environments including camping, hiking, travel, leisure, beach, boating, and other rugged and potentially weather and water prone environments. Applicants here have found that overtime, perhaps as a result of use and/or environment, a portion of the passive radiator may detach from the speaker chassis. This may be caused, for example, by water pressure on the passive radiator when the speaker falls or is otherwise submerged in water. Detachment of the passive radiator can result in damage to the electrical components (e.g., voice coil and magnet assembly of the active driver and other control circuitry located in the enclosure) and poor performance. Accordingly, as recognized by applicants, there is a need to improve the integrity of the attachment of the passive radiator while also allowing the speaker to be efficiently manufactured and assembled. 
       SUMMARY 
       [0006]    The subject matter of this invention is generally directed to an improved speaker assembly and methods of manufacture. The speaker may be designed to resist water penetration, may receive audio signals wirelessly, and/or may be battery powered. The speaker assembly includes a frame or chassis and one or more active drivers and at least one passive radiator mounted thereon, which when assembled together define an internal compartment. Support members are provided on opposing surfaces of the perimeter portion of the passive radiator to sandwich and secure the passive radiator in the desired position. 
         [0007]    In one construction, the chassis includes an aperture that has a radial region that generally corresponds in shape and dimension of the perimeter portion of the passive radiator. The radial region is configured to interface with the inner surface of the perimeter portion of the passive radiator to provide internal support thereto. The speaker also includes one or more perforated cover plates dimensioned and otherwise configured to attach to the speaker chassis and overlie the enclosure of the speaker cones and/or passive radiator. A retention gasket corresponding in dimension with the radial support region of the chassis aperture is positioned on top of the perimeter portion of the passive radiator in opposing position to the radial region of the aperture directly underlying the perimeter portion of the passive radiator. 
         [0008]    The retention gasket may be independent and/or integral with the inner region of the perforated cover plate overlying the passive radiator. The retention gasket and cover plate being dimensioned to firmly secure the passive radiator into the desired position by firmly sandwiching the perimeter portion of the passive radiator between the radial region of the aperture and the distal surface of the retention gasket. 
         [0009]    The passive radiator/chassis seal can be water tight and further reinforced with mechanical means such as screws or adhesives. 
         [0010]    Such constructions are capable of providing improved protection against water, moisture or contaminants from passing into the internal compartment while also capable of being efficiently manufactured. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0011]    The details of the invention, both as to its structure and operation, may be gleaned in part by study of the accompanying figures, in which like reference numerals refer to like parts. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, all illustrations are intended to convey concepts, where relative sizes, shapes and other detailed attributes may be illustrated schematically rather than literally or precisely. 
           [0012]      FIG. 1  is an isometric view of an exemplary fully-assembled stereo speaker showing the top, left, and front side thereof 
           [0013]      FIG. 2  is an isometric view of the stereo speaker of  FIG. 1  showing the top, right and front side thereof. 
           [0014]      FIG. 3  is an isometric view of the stereo speaker of  FIG. 1  showing the bottom, left and front side thereof 
           [0015]      FIG. 4  is an isometric view of the stereo speaker of  FIG. 1  showing the bottom, right and front side thereof 
           [0016]      FIG. 5  is an isometric view of the stereo speaker of  FIG. 1  showing the top, rear and right side thereof. 
           [0017]      FIG. 6  is an isometric view of the stereo speaker of  FIG. 1  showing the top, rear and left side thereof 
           [0018]      FIG. 7  is a perspective view of the stereo speaker of  FIG. 1  with the bottom cover removed from the speaker chassis to reveal the passive radiator and retention gasket. 
           [0019]      FIG. 8  is a front view of the stereo speaker of  FIG. 1  with the bottom cover removed from the speaker chassis to reveal a longitudinally extending region of the passive radiator retention gasket on the inside of the bottom cover. 
           [0020]      FIG. 9  is a top perspective view of the stereo speaker of  FIG. 1  with the bottom cover removed from the speaker chassis to reveal a perspective view of the passive radiator retention gasket on the inside of the bottom cover. 
           [0021]      FIG. 10  is another bottom perspective view of the stereo speaker of  FIG. 1  with the bottom cover portion removed from the speaker chassis to reveal the passive radiator and the surrounding speaker chassis. 
           [0022]      FIG. 11  is a cross-sectional view taken along A-A of  FIG. 8  that further illustrate the passive radiator, the underlying radial support region of the speaker chassis and the overlying retention gasket. 
           [0023]      FIG. 12  is a cross-sectional view of  FIG. 11  wherein the bottom cover is attached to the speaker chassis to further illustrate the relative position of the passive radiator, the underlying radial support region of the speaker chassis and the overlying retention gasket in the assembled state. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0024]    Disclosed herein are stereo speakers that include one or more active drivers and at least one passive radiator. The embodiments disclosed herein are described in the context of a wireless, battery powered, mobile stereo speaker as such speakers are of the type commonly used in outdoor environments. However, it should be understood that the teachings herein may be applied to other types of speakers and the mount described herein with regarding to the passive radiator may also be employed with respect to other external mounted components such as the active drivers or radiators. In addition, it should be understood that the teachings herein can be applied to more than stand-alone speakers. Indeed, it is contemplated that the teachings herein are equally applicable to any device that employs a passive radiator including and not limited to keyboards, computers, cameras, PDAs, and cell phones or waterproof/water-resistant or protective cases therefore. 
         [0025]    Illustrated in  FIGS. 1-6  illustrate an embodiment of an exemplary fully-assembled stereo speaker  100 .  FIGS. 7-10  illustrate the exemplary speaker in a partially disassembled state with the bottom cover removed and  FIGS. 11-12  illustrate cross-section views of the exemplary speaker  100  and the support and attachment structure of the passive radiator  200 . 
         [0026]    In the exemplary embodiment, the speaker is waterproof, wireless, battery powered and mobile. As used herein the term waterproof means that it is capable of withstanding immersion in one meter of water for up to 30 minutes consistent with IEC standard 60529 IPX7. Speaker  100  is depicted as being in the shape of generally rectangular box shape with rounded corners, however, it should be understood that the speaker  100  may take any shape desired. In the preferred embodiment the speaker is readily transportable by the user having dimensions approximately 5 inches in length, 2.5 inches in height, and 3.5 inches depth and approximately one pound in weight. 
         [0027]    The speaker  100  includes a top side  102 , a bottom side  104 , a front side  106 , a rear side  108 , a left side  110 , and a right side  112  that surround an internal housing. The front side  106  includes a perforated  114  front cover  132  that covers the active driver  174  (shown in  FIG. 8  through the perforations  114 ). The perforations/holes  114  are provided to allow sound waves, generated by the vibration of an active driver  174  to pass through. Although not fully depicted the active drivers  174  are generally circular cone radiators mounted on the front side  172  of the speaker chassis  180 . The front cover  132  is removably attached to the chassis  180  via mechanical means such as screws or latches or via adhesive means or a combination thereof. The chassis  180  provides the primary support structure of the speaker  100  to mount the speaker radiators within apertures therein and defines the internal compartment  170 . 
         [0028]    In a preferred embodiment of particular relevance for waterproof or water resistant implementations, the chassis  180  may be a unitary integrally formed polymer molded or extruded construct with multiple apertures for the speaker radiators and any other passage required, such as USB communication or charging port, power connector, audio connector, Ethernet connection, reset or control buttons or indicators, battery power indicator or controls, which in the present embodiment may be housed under the screw-on cap  120  that mates with the chassis  180  and protects the electrical sockets and interfaces thereunder. 
         [0029]    The chassis  180  is preferably formed of suitably rigid material that is capable of withstanding external pressure and maintain the desired tune of the speaker. Portions of the chassis  180  may be externally exposed while other portions may underlie covers (e.g.,  132  front cover,  140  bottom covers), caps (e.g.  120 ) and/or may be overlaid, over-molded, co-molded with another, perhaps more flexible, elastic, less rigid, or cushioning material. Thus, this second material may allow for pushbutton external control such as volume, power or play control while also provide a protective cushioning layer for impact. In the illustrated embodiment, or less rigid, elastic polymer layer covers the top of the chassis  180  along the top region  130  (including over the volume, power, and play user control buttons), in rear regions  118 , and the outside of the bottom cover  140 , discussed in more detail below. The perimeter edge region of the front side  106  may also be overlaid with a protective cushioning layer as well as the left and right side  110  and  112  regions or protrusions thereon. 
         [0030]    The bottom cover  140  includes an internal side  150  and an external side  142  is configured to be removably attached to the underside or bottom of the chassis  180  for example by mechanical means, e.g., screws, rivets, or latches or the like. The external side  142  may include a plurality of feet  146  to provide a support the speaker  100  in the upright position. As with the front cover  132 , the bottom cover  140  is perforated with a plurality of holes  148  for allowing sound waves, generated by the vibration of a passive radiator  200  (shown in FIGS.  7  and  10 - 12 ), to radiate externally from the internal compartment  170 . The passive radiator  200  can be the same or similar to the main or active drivers  174  but without a voice coil and magnet assembly. The physical forward/back movement of the main driver  174  fluctuates the air pressure in the sealed internal compartment  170 , which in turn fluctuates the passive radiator  200  to generate sound. 
         [0031]    In the exemplary speaker, the passive radiator  200  is generally in the shape of an elongated oval and includes a relatively rigid central region  202  and a relatively flexible region  210  that extends radially from the outer perimeter portion  204  of the central region  202  to the radial perimeter portion  214  of the flexible region  210 . The flexible perimeter region  210  includes one or more perimeter baffles  216  to allow the radiator to pulsate inward and outwardly with movement as it fluctuates with sound. The central part  202  may include a rigid tuning mass  206  and external elastic or flexible skin or layer  208  overlaid thereon that extends radially to form the flexible region  210  including the radial perimeter portion  214 . 
         [0032]    The radial perimeter portion  214  of the flexible element  210  is mounted to the chassis  180  within a correspondingly dimensioned passive radiator aperture therein which is defined as residing between radial region  190  of the aperture chassis. When mounted, the radial perimeter portion  214  of the passive radiator  200  overlies the externally facing surface of the radial region  190 . The inner surface of the radial perimeter portion  214  of the passive radiator  200  may be glued or adhered to the outer surface of the radial region  190  of the chassis  180 . In a preferred construction an elastic epoxy or rubber glue is used. Once the passive radiator is attached to the bottom portion of the chassis  180  (or in the case of a multi-part chassis, the bottom portion of the chassis positioned and attached to the other mating portion of the chassis) the internal compartment  170  is sealed. 
         [0033]    When the bottom cover  140  is attached (via mechanical means such as rivets, screws, or adhesive) there is a void between the internal side  150  of the bottom cover and the outer surface of the passive radiator  200 , which allows the passive radiator to move freely inwardly and outwardly as it fluctuates with sound. As best depicted in  FIGS. 11-12 , the internal side  150  of the bottom cover  140  is provided with a retention gasket  160  configured to be shaped and dimensioned to correspond and aligned with the radial portion  214  of the flexible element  210  and the underlying radial support region  190  in the chassis  180  that defines the passive radiator aperture. The retention gasket  160  is also dimensioned in height so that its distal surface presses firmly on the radial portion  214  of the flexible element  210  to firmly sandwich the radial perimeter portion  214  of the flexible element  210  against the underlying radial support region  190  of the chassis  180  when the bottom cover  140  is secured to the chassis  180 . Such a construction is easily assembled and capable of providing additional integrity to the passive radiator/speaker chassis seal while also providing the needed space  184  to allow the passive radiator to pulsate freely during operation yet also be protected by the perforated bottom cover  140 . 
         [0034]    The retention gasket  160  can be formed of continuous or non-continuous segments such as that depicted in  FIGS. 11-12 . A portion of the retention gasket  160  can be configured to have a locking mechanism (e.g., click) to lock the bottom cover  140  and the chassis  180  when the speaker is fully assembled. The retention gasket  160  can be made of a flexible but firm material such as plastic or metal or other suitable material. Its distal surface can include a slight curvature which may be helpful in avoiding tearing of the passive radiator. Alternatively, the distal surface of the retention gasket  160  may have various shapes (hills, valleys, ridges, etc.) or combinations of shapes. The outer surface of the opposing radial support region  190  may have corresponding shape to that of the mating distal surface of the retention gasket  160  to facilitate a more firm attachment. The retention gasket  160  may be attached in any suitable manner to the internal side  150  of the bottom cover  140 , may be integrally formed to the internal side of the bottom cover  140  or may be entirely detachable or independent from the internal side  150  of the bottom cover  140 . It is contemplated that portions of the retention gasket  160  may be attached or integral to the bottom cover  140  while other portions may be detachable or independent. It is also contemplated that the retention gasket  160  may be secured directly and/or independently to the underlying radial support region  190  of the speaker chassis  180  via screws or other suitable mechanical or adhesive means. In such a construction the bottom cover  140  may provide additional support to the retention gasket  160 . 
         [0035]    While the invention has been described in connection with specific examples and various embodiments, it should be readily understood by those skilled in the art that many modifications and adaptations of the invention described herein are possible without departure from the spirit and scope of the invention as claimed hereinafter. Thus, it is to be clearly understood that this application is made only by way of example and not as a limitation on the scope of the invention claimed below. The description is intended to cover any variations, uses or adaptation of the invention following, in general, the principles of the invention, and including such departures from the present disclosure as come within the known and customary practice within the art to which the invention pertains.