Abstract:
Example transducer assemblies are described here. An example transducer assembly may include a frame, a magnet carried by the frame, a voice coil operably coupled to the magnet, and a diaphragm. The diaphragm has an outer portion surrounding a central portion. The outer portion of the diaphragm has a generally concave shape, and the central portion of the diaphragm has a generally convex shape. The central portion of the diaphragm comprises a first surface facing toward the voice coil, and a second surface facing away from the voice coil. A coupler connects the voice coil to the first surface of the central portion.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority under 35 U.S.C. §120 to, and is a continuation of, U.S. patent application Ser. No. 14/885,668, filed on Oct. 16, 2015, entitled “Loudspeaker Configuration,” which is incorporated herein by reference in its entirety. 
         [0002]    U.S. patent application Ser. No. 14/885,668 claims priority under 35 U.S.C. §120 to, and is a continuation of, U.S. patent application Ser. No. 14/021,813, filed on Sep. 9, 2013, entitled “Loudspeaker Configuration,” issued as U.S. Pat. No. 9,232,314 on Jan. 1, 2016, which is also incorporated herein by reference in its entirety. 
         [0003]    This application is also related to U.S. patent application Ser. No. 14/021,831, filed on Sep. 9, 2013, entitled “Loudspeaker Assembly Configuration”, the contents of which are fully incorporated by reference herein. 
     
    
     FIELD OF THE DISCLOSURE 
       [0004]    The disclosure is related to consumer goods and, more particularly, to methods, systems, products, features, services, and other items directed to media playback or some aspect thereof. 
       BACKGROUND 
       [0005]    A loudspeaker in the context of the present application is an electroacoustic transducer that produces sound in response to an electrical audio signal input. Originally, non-electrical loudspeakers were developed as accessories to telephone systems. Today, electronic amplification for applications such as audible communication and enjoyment of music has made loudspeakers ubiquitous. 
         [0006]    A common form of loudspeaker uses a diaphragm (such as, for example, a paper cone) supporting a voice coil electromagnet acting on a permanent magnet. Based on the application of the loudspeaker, different parameters may be selected for the design of the loudspeaker. For instance, the frequency response of sound produced by a loudspeaker may depend on the shape, size, and rigidity of the diaphragm, and efficiency of the voice coil electromagnet, among other factors. Accordingly, the diaphragm and voice coil electromagnet may be selected based on a desired frequency response of the loudspeaker. In some cases, for improved reproduction of sound covering a wide frequency range, multiple loudspeakers may be used collectively, each configured to optimally reproduce different frequency sub-ranges within the wide frequency range. 
         [0007]    As applications of loudspeakers continue to broaden, different loudspeakers designed for particular applications continue to be developed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    Features, aspects, and advantages of the presently disclosed technology may be better understood with regard to the following description, appended claims, and accompanying drawings where: 
           [0009]      FIGS. 1A, 1B, and 1C  show example conventional configurations of a loudspeaker. 
           [0010]      FIG. 2  shows a first example configuration of a loudspeaker, according to an embodiment of the present application; and 
           [0011]      FIG. 3  shows a second example configuration of a loudspeaker, according to an embodiment of the present application. 
       
    
    
     DETAILED DESCRIPTION 
     I. Overview 
       [0012]    Embodiments described herein involve loudspeaker configurations that allow for a loudspeaker to have reduced height. The reduced height of the loudspeaker may allow the loudspeaker to be installed in shallow compartments where conventional non-shallow speakers may not otherwise fit. 
         [0013]    In one example, a configuration of a loudspeaker may involve a continuous diaphragm extending across a frame of the loudspeaker and covering a voice coil of an electromagnet transducer of the loudspeaker. In other words, the voice coil is covered by the diaphragm, rather than by a dust cap, as may be the case in conventional loudspeaker configurations. Dust caps for covering voice coils in a loudspeaker may add height to the loudspeaker transducer, thereby adding height to the loudspeaker.  FIG. 1A  shows an example conventional loudspeaker configuration  100  including a voice coil  102 , and diaphragm  104 . As shown, the voice coil  102  may protrude the diaphragm  104 , and accordingly, a dust cap  106  may be provided to cover the voice coil  102 . In this case, the dust cap  106  may add a height  114  to the height of the loudspeaker. 
         [0014]    As such, the loudspeaker in this example configuration may have a reduced height because the voice coil is covered by the continuous diaphragm rather than a dust cap. Further, conventional loudspeakers configured with dust caps may require additional component costs and manufacturing time to install the dust cap. As such, a loudspeaker with a continuous diaphragm covering the voice coil may further involve reduced costs and manufacturing time. 
         [0015]    In another example, a configuration of the loudspeaker may involve a suspension element, sometimes referred to as a “spider,” attached circumferentially between a diaphragm of the loudspeaker and a frame of the loudspeaker. In this example, the spider is attached between the frame and the diaphragm rather than between the frame and a voice coil of an electromagnet transducer of the loudspeaker, as may be the case in conventional speaker configurations. In the case of conventional speaker configurations in which the spider is attached to a voice coil, the voice coil may have a required height to provide sufficient clearance for movement of the spider attached to the voice coil during operation of the loudspeaker. 
         [0016]      FIG. 1B  shows an example loudspeaker configuration  120  having the voice coil  102  and diaphragm  104  as discussed above in connection to  FIG. 1A . In this case, the voice coil  102  may be suspended within a gap of a magnetic structure  108 , and may be configured to move along an internal portion of the magnetic structure  108  in response to an electric signal to cause the diaphragm to generate sound. As shown, a distance  110   b  may be provided between the voice coil  102  and a bottom of the gap, and a distance  110   a  may be provided between a top of the outer portion of the magnetic structure  108  and a bottom surface of the diaphragm to provide clearance for the voice coil  102  to move in response to the electric signal. In one example, this clearance may be referred to as an excursion clearance. In some cases, the distance  110   a  and the distance  110   b  may be substantially the same. 
         [0017]      FIG. 1C  shows an example conventional loudspeaker configuration  130  having the voice coil  102 , the diaphragm  104 , and magnetic structure  108  as discussed above in connection to  FIGS. 1A and/or 1B . In this case, however, a spider  112  may be attached to the voice coil  102  as suggested above. As shown, an additional height  116  on the voice coil  102  is provided to accommodate the attachment of the spider  112  while providing the same excursion clearance of distance  110   a.  As such, a configuration in which the spider is attached between the frame and the diaphragm rather than between the frame and the voice coil may eliminate the need for the additional height on the voice coil, reduce the required height of the voice coil, thereby allowing the loudspeaker to have a reduced height. 
         [0018]    As indicated above and further discussed below, the present application involves a loudspeaker configuration. The loudspeaker includes a frame, a magnetic structure having a magnetic gap, a voice coil suspended at least partially within the magnetic gap, and a first suspension element having an inner rim and an outer rim. The first suspension element is attached to the frame along the outer rim of the first suspension element. The loudspeaker configuration also includes a diaphragm having a continuous central portion and an outer portion. The diaphragm is attached to the voice coil via a first coupler to a lower surface of the continuous central portion. The diaphragm is attached to the inner rim of the first suspension element along an outer edge of the outer portion such that the diaphragm suspends from the frame. The loudspeaker configuration further includes a second suspension element having an inner rim and an outer rim. The second suspension element is attached to the frame along the outer rim of the second suspension element. The inner rim of second suspension element is attached to the diaphragm via a second coupler along a circumferential middle section of the diaphragm between the continuous central portion and outer portion of the diaphragm. 
         [0019]    In another aspect, a diaphragm structure for a loudspeaker is provided. The diaphragm structure includes a continuous central portion having a lower surface. The lower surface of the continuous central portion is attached to a voice coil of the loudspeaker via a first coupler. The diaphragm structure also includes an outer portion having an outer edge. The outer edge of the outer portion is attached to an inner rim of a first suspension element attached to a frame of the loudspeaker such that the diaphragm suspends from the frame of the loudspeaker. The diaphragm structure further involves a circumferential middle section between the continuous central portion and outer portion of the diaphragm. The circumferential middle section is coupled via a second coupler to an inner rim of a second suspension element. The second suspension element is attached to the frame of the loudspeaker along an outer rim of the second suspension element. 
         [0020]    Other embodiments, as those discussed in the following and others as can be appreciated by one having ordinary skill in the art are also possible. 
       II. Example Loudspeaker Configurations 
       [0021]    As suggested above, the present application provides loudspeaker configurations that allow for a loudspeaker to have reduced height.  FIG. 2  shows a first example configuration of a loudspeaker  200 , according to an embodiment of the present application. The loudspeaker  200  of  FIG. 2  is represented as a profile or cut-out view of an example loudspeaker. As such, elements of the loudspeaker  200  are substantially mirrored along a center axis  230 . In some cases, mirrored elements may be part of the same loudspeaker component. 
         [0022]    As shown, the loudspeaker  200  includes a frame  202 , a magnetic structure  210 , a voice coil  214 , a first suspension element  208 , a diaphragm having a continuous central portion  204   a  and an outer portion  204   b,  and a second suspension element  220 . The loudspeaker  200  further includes a first coupler  224  and a second coupler  216 . 
         [0023]    The frame  202  or “basket” of the loudspeaker  200  may be designed to maintain alignment of other components in the loudspeaker. The frame may be, for example, cast from aluminum alloy, stamped from steel sheets, or molded from plastic. 
         [0024]    The magnetic structure  210  and the voice coil  214  may be components of an electromagnetic transducer of the loudspeaker  200 . As shown, the magnetic structure may have a magnetic gap, and the voice coil  214  may be suspended at least partially within the magnetic gap. The electromagnetic transducer of the loudspeaker  200  may be configured to vibrate longitudinally in response to an electric current run through the voice coil  214 . 
         [0025]    The diaphragm, which may be attached to the voice coil  214  via the first coupler  224 , vibrates in response to the vibration of the voice coil  214 , thereby producing sound. The diaphragm may be made of, for example, paper, plastic, metal, or composite materials such as cellulose paper, carbon fiber, and Kevlar, etc. Other materials may also be possible. The sound output level and frequency response of the loudspeaker  200  may be dependent on the material and dimensions of the diaphragm. As shown in  FIG. 2 , the diaphragm of the loudspeaker  200  may include a continuous central portion  204   a,  and an outer portion  204   b.  In one example, the first coupler  224  may include a cone coupler fitted circumferentially around a portion of the voice coil and adhered to a lower surface of the continuous central portion  204   a  of the diaphragm. 
         [0026]    The first suspension element  208  and the second suspension element  220  may make up a suspension system of the loudspeaker  200  configured to keep the voice coil  214  centered in the magnetic gap of the magnetic structure  210  and provide a restoring force to return the diaphragm to a neutral position after movement of the diaphragm responsive to vibrations of the voice coil  214 . 
         [0027]    The first suspension element  208  or “surround” of the loudspeaker may have an inner rim and an outer rim. As shown in  FIG. 2 , the first suspension element  208  may be attached to the frame  202  along the outer rim of the first suspension element  208 , and an inner rim of the first suspension element  208  may be attached to the diaphragm along an outer edge of the outer portion  204   b  of the diaphragm. The first suspension element  208  may be made of rubber, polyester foam, or corrugated, resin coated fabric, for example. Other materials may also be possible. The sound output level and frequency response of the loudspeaker  200  may be dependent on the material and dimensions of the first suspension element  208 . 
         [0028]    The second suspension element  220  or “spider” of the loudspeaker  200  may have an inner rim and an outer rim. As shown in  FIG. 2 , the outer rim of the second suspension element  220  may be attached to the frame  202 , and the inner rim of the second suspension element  220  may be attached to the diaphragm via the second coupler  216 . In one example, the second coupler  216  may include an adhesive substance configured to bind the second suspension element  220  to the diaphragm. The second suspension element  220  may be made of a treated fabric material, flexible rubber, or flexible elastomer, for example. Other materials may also be possible. The sound output level and frequency response of the loudspeaker  200  may be dependent on the material and dimensions of the second suspension element  220 . In one example, the second suspension element  220  may have a concentrically corrugated structure. 
         [0029]    The sound output level and frequency response of the loudspeaker  200  may further be dependent on an orientation of the second suspension element  220 . In one case, the second suspension element  220  may be oriented such that the suspension element  220  is substantially horizontal or parallel to an orientation of the diaphragm. 
         [0030]    As shown, the second suspension element  220  may be attached to the diaphragm along a circumferential middle section of the diaphragm between the continuous central portion  204   a  and outer portion of the diaphragm  204   b.  In one example, the second coupler  216  may be a circumferential coupler concentric with the continuous central portion  204   a  and outer portion  204   b  of the diaphragm. In this case, the circumferential middle section of the diaphragm may be defined by the circumferential second coupler  216 . 
         [0031]    As shown in  FIG. 2 , the continuous central portion  204   a  of the diaphragm may include a continuous dome-shaped diaphragm and the outer portion  204   b  of the diaphragm may include a cone-shaped diaphragm concentrically positioned about the continuous central portion  204   b  of the diaphragm. In one example the cone-shaped diaphragm may have a lower circumferential opening and an upper circumferential opening wider than the lower circumferential opening. In this example, an outer rim of the continuous dome-shaped diaphragm may be attached to an edge of the lower circumferential opening of the cone-shaped diaphragm. 
         [0032]    In one case, the continuous dome-shaped diaphragm may be coupled to the cone-shaped diaphragm along the circumferential middle section of the diaphragm. As such, the continuous dome-shaped diaphragm may be coupled to the cone-shaped diaphragm via the second coupler  216 , which also attaches the second suspension element  220  to the diaphragm along the circumferential middle section of the diaphragm. For instance, the second suspension element  220  may be attached to the edge of the lower circumferential opening of the cone-shaped diaphragm along the circumferential middle section of the diaphragm. In some instances, the circumferential middle section of the diaphragm may be defined by where the continuous dome-shaped diaphragm and the cone-shaped diaphragm are coupled. 
         [0033]    As one having ordinary skill in the art may appreciate, the sound output level and frequency response of the loudspeaker  200  may be dependent on the sizes and depths of the continuous dome-shaped diaphragm and cone-shaped diaphragm. 
         [0034]      FIG. 3  shows a second example configuration of a loudspeaker  300 , according to an embodiment of the present application. Similar to the loudspeaker  200  of  FIG. 2 , the loudspeaker  300  of  FIG. 3  is represented as a profile or cut-out view of an example loudspeaker. As such, elements of the loudspeaker  300  are substantially mirrored along a center axis  330 . In some cases, mirrored elements may be part of the same loudspeaker component. 
         [0035]    As shown, the loudspeaker  300  includes a frame  302  similar to that of the frame  202 , a magnetic structure  310  similar to that of the magnet structure  210 , a voice coil  314  similar to that of the voice coil  214 , a first suspension element  308  similar to that of the first suspension element  208 , and a second suspension element  320  similar to that of the second suspension element  220 . As with the loudspeaker  200 , the loudspeaker  300  also includes a first coupler  324  similar to that of the first coupler  224  and a second coupler  316  similar to that of the second coupler  216 . 
         [0036]    The loudspeaker  300  also includes a diaphragm  304 , which like the diaphragm of loudspeaker  200 , may be made of, for example, paper, plastic, metal, or composite materials such as cellulose paper, carbon fiber, and Kevlar, etc., and may be configured to produce sound responsive to vibrations of the voice coil  314  attached to the diaphragm  304  via the first coupler  324 . 
         [0037]    Different from the diaphragm of loudspeaker  200 , the diaphragm  304  may have a continuous central portion that may be structurally indistinguishable from an outer portion of the diaphragm  304 . In other words, the diaphragm  304  may be of a single composition of material, rather than a combination of a continuous dome-shaped diaphragm and a cone-shaped diaphragm as is the case of loudspeaker  200 . As such, a circumferential middle section of the diaphragm  304  may simply be defined by where the second coupler  316  attaches the diaphragm  304  to the second suspension element  320 . 
         [0038]    Nevertheless, a concentric position of the circumferential middle section where the second coupler  316  attaches the diaphragm  304  to the second suspension element  320  is not arbitrary. As one having ordinary skill in the art may appreciate, the sound output level and frequency response of the loudspeaker  300  may be dependent on the concentric position of the second coupler  316 . 
         [0039]    Other example configurations and embodiments may also be possible. 
       IV. Conclusion 
       [0040]    As indicated above, the present application involves a loudspeaker configuration. The loudspeaker includes a frame, a magnetic structure having a magnetic gap, a voice coil suspended at least partially within the magnetic gap, and a first suspension element having an inner rim and an outer rim. The first suspension element is attached to the frame along the outer rim of the first suspension element. The loudspeaker configuration also includes a diaphragm having a continuous central portion and an outer portion. The diaphragm is attached to the voice coil via a first coupler to a lower surface of the continuous central portion. The diaphragm is attached to the inner rim of the first suspension element along an outer edge of the outer portion such that the diaphragm suspends from the frame. The loudspeaker configuration further includes a second suspension element having an inner rim and an outer rim. The second suspension element is attached to the frame along the outer rim of the second suspension element. The inner rim of second suspension element is attached to the diaphragm via a second coupler along a circumferential middle section of the diaphragm between the continuous central portion and outer portion of the diaphragm. 
         [0041]    In another aspect, a diaphragm structure for a loudspeaker is provided. The diaphragm structure includes a continuous central portion having a lower surface. The lower surface of the continuous central portion is attached to a voice coil of the loudspeaker via a first coupler. The diaphragm structure also includes an outer portion having an outer edge. The outer edge of the outer portion is attached to an inner rim of a first suspension element attached to a frame of the loudspeaker such that the diaphragm suspends from the frame of the loudspeaker. The diaphragm structure further involves a circumferential middle section between the continuous central portion and outer portion of the diaphragm. The circumferential middle section is coupled via a second coupler to an inner rim of a second suspension element. The second suspension element is attached to the frame of the loudspeaker along an outer rim of the second suspension element. 
         [0042]    The descriptions above disclose various example systems, apparatus, and articles of manufacture. Such examples are merely illustrative and should not be considered as limiting. Accordingly, while the above describes example systems, apparatus, and/or articles of manufacture, the examples provided are not the only way(s) to implement such systems, apparatus, and/or articles of manufacture. 
         [0043]    Additionally, references herein to an “embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one example embodiment of the invention. The appearances of this phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. As such, the embodiments described herein, explicitly and implicitly understood by one skilled in the art, can be combined with other embodiments. 
         [0044]    Numerous specific details are set forth to provide a thorough understanding of the present disclosure. However, it is understood to those skilled in the art that certain embodiments of the present disclosure can be practiced without certain, specific details. In other instances, well known methods, procedures, components, and circuitry have not been described in detail to avoid unnecessarily obscuring aspects of the embodiments. Accordingly, the scope of the present disclosure is defined by the appended claims rather than the forgoing description of embodiments.