Abstract:
A speaker bracket disposed between a front end circumferential wall of a speaker frame and a speaker mounting portion of a cabinet as an adjuster, the speaker bracket includes a body formed into an approximate ring shape. The body includes a first surface and a second surface. The first surface has a frame adjusting portion to be secured to the front end circumferential wall. The second surface has a cabinet adjusting portion fixed to the speaker mounting portion. The frame adjusting portion is attachable to the front end circumferential wall from both a front side and a rear side of the speaker frame.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is based upon and claims the benefit of priority from Japanese Patent Application NO. P2005-378397, filed Dec. 28, 2005, the entire contents of which are incorporated herein by reference.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to a speaker bracket and a speaker.  
         [0004]     2. Background Art  
         [0005]     A speaker provides predetermined acoustic reproduction, generally by fixing a speaker unit to a speaker mounting portion, such as a cabinet, that is formed on a baffle board.  
         [0006]     A common speaker unit is designed so that a diaphragm and a magnetic circuit, for driving the diaphragm, are assembled in a speaker frame and cabinet mounting portions are prepared for the front side wall of the speaker frame, that are to be secured to a speaker mounting portion by screws.  
         [0007]     But when, for example, speaker mounting portions are formed on the doors of vehicles, because of positional relationships, relative to other components with which the doors may be equipped, and spatial limitations, the sizes of these portions frequently differ slightly from the cabinet mounting portions provided for speaker units.  
         [0008]     However, to resolve such mounting size mismatches between the front side wall cabinet mounting portions and the speaker mounting portions, a variety of types of speaker frames are prepared for which the sizes and the locations of the cabinet mounting portions differ, productivity is adversely affected and manufacturing costs rise sharply.  
         [0009]     Therefore, various speaker designs have been proposed so that, to attach a speaker unit to a speaker mounting portion, a speaker bracket is positioned between a front end circumferential wall of the unit and the speaker mounting portion and is used to adjust a mounting size between the front end circumferential wall and the speaker mounting portion (see, for example, JP-A-2003-63316 and JP-A-10-250492).  
         [0010]     A speaker unit is packaged for shipment using packaging components, formed, for example, of cardboard, corrugated cardboard or Styrofoam, to immobilize and cushion the unit and prevent impact and other damage while the unit is being transported and handled prior to delivery.  
         [0011]     Conventional packaging structures are shown in  FIGS. 1 and 2 .  
         [0012]     The packaging structure in  FIG. 1  is an example wherein one speaker unit  1  is immobilized by employing two packaging components  3  and  4 .  
         [0013]     The packaging structure in  FIG. 2  is an example wherein a bracket  2 , used as a mounting size adjustment, is assembled with a speaker  1 , and the speaker  1  and the bracket  2  are immobilized by employing two packaging components  5  and  6 .  
         [0014]     In  FIGS. 1 and 2 , for the speaker  1 , cabinet mounting portions (screw fastening portions)  11   a , which are to be fixed to a speaker mounting portion, such as a cabinet, are formed on a front end circumferential wall  11   b  of a speaker frame  11 , and a diaphragm  13  and a magnetic circuit  14 , for driving the diaphragm  13 , are assembled with the speaker frame  11 .  
         [0015]     In either case, the diaphragm  13  is cone shaped, and to attach this diaphragm  13  to the speaker frame  11 , the outer wall of a roll edge  15 , which is integrally formed with the outer edge of the diaphragm  13 , is secured to an edge fixing portion (not shown) internally provided along the front end circumferential wall  11   b.    
         [0016]     The bracket  2  is formed almost as a ring, and on one face, frame aligning portions  51  are formed that are to be fastened to the rear face of the front end circumferential wall  11   b  of the speaker frame  1  . Onthe other face of the bracket  2 , cabinet aligning portions  52  are provided that are to be fixed to the speaker mounting portion, such as a cabinet, and are used as fittings for the mounting sizes of the front end circumferential wall  11   b  and the speaker mounting portion when the speaker  1  is attached to the speaker mounting portion.  
         [0017]     In this case, the packing components  3  to  6  are made, for example, of Styrofoam, and the form of their shapes and sizes are such that they are consonant with the outer shape and size of the speaker unit  1 .  
         [0018]     For the packaging components  3  and  5 , a step portion  3   b , which contacts the rear end face of the front end circumferential wall  11   b , and a step portion  5   b , which contacts the rear end face of the bracket  2  assembled with the front end circumferential wall  11   b , are respectively formed around recessed portions  3   a  and  5   a , where the rear portion of the speaker  1  is fitted.  
         [0019]     Since the front end circumferential wall  11   b  is gripped between the packaging component  4  or  6  and the step portion  3   b  or  5   b  of the packaging component  3  or  5 , the speaker unit  1  is prevented from popping of the recessed portion  3   a  or  5   a  due to vibration or an impact that occurs in transit, prior to delivery.  
         [0020]     However, according to the conventional packaging structure that prevents the speaker unit  1  from popping out of the packaging components  3  and  5 , the packaging components  4  and  6  directly hold the front face of the front end circumferential wall  11   b . Further, in order to avoid the interference of the internal walls of the packaging components  4  and  6  with the roll edge  15 , the length w of a projected portion  4   a  or  6   a , which extends over the front end circumferential wall  11   b,  is limited to only a small value.  
         [0021]     As a result, only a small contact area is provided for the projected portion  4   a  or  6   a  that holds the speaker unit  1 . Thus, should a box in which a heavy speaker unit  1  is packaged be dropped, shear stress, having a strength commensurate with the height from which dropped, will act on the unit area, and the projected portion  4   a  or  6   a  may be destroyed or deformed. Accordingly, the speaker unit  1  could be shifted and damaged.  
         [0022]     In order to prevent the occurrence of such a problem, according to one corrective proposal, the entire front face of the speaker unit  1  is covered with a protective cover, as an additional packaging component, that increases the length w of the projected portion  4   a  or  6   a . However, when this method is used, because the number of packaging components is increased, the packaging structure becomes more complicated, so that either the design of packaging becomes more difficult or manufacturing costs are increased.  
       SUMMARY OF THE INVENTION  
       [0023]     Problems to be resolved by one embodiment according to the invention are: a problem that has been encountered with the conventional art, i.e., a problem in that since an extended length cannot be provided for the projected portion of a packaging component that holds a speaker, the projected portion may tend to be destroyed or deformed if a package is dropped, and accordingly, since the projected portion may be destroyed or deformed, the speaker may be easily damaged; and a problem associated with reinforcing the packaging protection provided for a speaker, i.e., a problem in that since the number of packaging components would have to be increased, the packaging structure would become more complicated and either packaging design would be excessively difficult or manufacturing costs would be increased.  
         [0024]     To solve these problems, according to a first aspect of the invention, there is provided a speaker bracket disposed between a front end circumferential wall of a speaker frame and a speaker mounting portion of a cabinet as an adjuster. The speaker bracket includes a body formed into an approximate ring shape. The body includes a first surface and a second surface. The first surface has a frame adjusting portion to be secured to the front end circumferential wall. The second surface has a cabinet adjusting portion fixed to the speaker mounting portion. The frame adjusting portion is attachable to the front end circumferential wall from both a front side and a rear side of the speaker frame.  
         [0025]     According to a second aspect of the invention, there is provided a speaker mounted on a speaker mounting portion of a cabinet. The speaker includes a speaker unit and a speaker bracket. The speaker unit includes a speaker frame including a front end circumferential wall having a cabinet mounting portion formed on the front end circumferential wall, a diaphragm mounted on the speaker frame, and a magnetic circuit that drives the diaphragm, and that is mounted on the speaker frame. The speaker bracket is disposed between the front end circumferential wall and the speaker mounting portion as an adjuster. The speaker bracket includes a body formed into an approximate ring shape. The body includes a first surface and a second surface. The first surface has a frame adjusting portion to be secured to the front end circumferential wall. The second surface has a cabinet adjusting portion to be fixed to the speaker mounting portion. The frame adjusting portion is attachable to the front end circumferential wall from both a front side and a rear side of the speaker frame. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0026]     The present invention may be more readily described with reference to the accompanying drawings:  
         [0027]      FIG. 1  is a vertical cross-sectional view of a packing structure for a conventional speaker;  
         [0028]      FIG. 2  is a vertical cross-sectional view of a packing structure for a case wherein a speaker bracket is attached to the conventional speaker;  
         [0029]      FIG. 3  is an exploded perspective view of a case wherein a speaker bracket and a speaker according to a first embodiment of the present invention are to be mounted on a speaker mounting portion;  
         [0030]      FIG. 4  is a cross-sectional view of the state wherein the speaker in  FIG. 3  is mounted on the speaker mounting portion;  
         [0031]      FIG. 5  is a perspective view of the positional relationship of the speaker unit and the speaker bracket when the speaker in  FIG. 3  is to be packed;  
         [0032]      FIG. 6  is a vertical cross-sectional view of the packed state of the speaker in  FIG. 3 ;  
         [0033]      FIG. 7  is an exploded perspective view of a case wherein a speaker bracket and a speaker according to a second embodiment of the present invention are to be mounted on a speaker mounting portion;  
         [0034]      FIG. 8  is a front view of the speaker bracket in  FIG. 7 ;  
         [0035]      FIG. 9  is a rear view of the speaker bracket in  FIG. 7 ;  
         [0036]      FIG. 10  is a cross-sectional view taken along A-A in  FIG. 8 ;  
         [0037]      FIG. 11  is a diagram showing the speaker bracket in  FIG. 8 , viewed from a direction indicated by an arrow B;  
         [0038]      FIG. 12  is a cross-sectional view taken along C-C in  FIG. 9 ; and  
         [0039]      FIG. 13  is an enlarged diagram showing a portion D in  FIG. 8 ;  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0040]     A speaker bracket and a speaker according to the present invention will be described.  
         [0041]     The speaker of this invention includes a speaker unit and a speaker bracket. The speaker unit is obtained by assembling a diaphragm and a magnetic circuit for driving the diaphragm, with a speaker frame wherein cabinet mounting portions, which are to be fixed to a speaker mounting portion, such as a cabinet, are formed on a front end circumferential wall. The speaker bracket is positioned between the front end circumferential wall and the speaker mounting portion when the speaker unit is attached to the speaker mounting portion, and is used for matching the mounting size between the front end circumferential wall and the speaker mounting portion.  
         [0042]     The speaker bracket is formed almost like a ring, and on one face, frame aligning portions are formed that are to be fastened to the front end circumferential wall of the speaker frame, while on the other face, cabinet aligning portions are formed that are to be fixed to the speaker mounting portion, such as a cabinet, that secures the front end circumferential wall.  
         [0043]     For the speaker bracket, the frame aligning portions are formed so as to be attachable from the front end circumferential wall, from the front and the rear of the speaker frame.  
         [0044]     According to the above arrangement, during the packaging process, the speaker bracket is attached, from the front of the speaker unit, to the front end circumferential wall of the speaker frame and to the speaker unit. As a result, the speaker bracket serves as a protective cover that encloses the front face of the speaker, while providing a protective gap in front of the diaphragm of the speaker unit.  
         [0045]     Sequentially, when the speaker is packed in a state wherein the speaker bracket has been attached, from the front of the speaker unit, to the front end circumferential wall of the speaker frame, the projected portion of a packaging component, which prevents the speaker unit from popping out to the front, does not directly contact the front end circumferential wall of the speaker frame, and holds the other face of the speaker bracket that includes the cabinet aligning portions. Therefore, when the length of the projected portion is increased toward the center axis of the speaker, the projected portion does not adversely affect the roll edge that projects outward, from inside the front end circumferential wall, to a position forward of the speaker. Thus, a large contact area is provided for the projected portion that holds the speaker bracket.  
         [0046]     Therefore, if a box in which a speaker unit is packaged is dropped, the shear force imposed on the projected portion of the packaging component by the speaker unit is received by and distributed across a large contact area, and the destruction or deformation of the projected portion can be prevented. Thus, the speaker can be immobilized and protected from damage.  
         [0047]     Further, in this invention, the speaker bracket, which is originally located between a speaker and a speaker mounting portion to adjust a mounting size, is attached to the front end circumferential wall from the front of the speaker frame. Thus, the speaker bracket functions as a protective cover for the front cover of the speaker unit. Since the speaker bracket provides reinforced protection for the speaker unit, the need for an additional packaging component that would furnish such reinforcement is eliminated.  
         [0048]     Therefore, the packaging structure is simplified and prevented from becoming complicated due to an increase in the packaging components, so that a box for packaging can be easily designed and manufacturing costs can be reduced.  
       The First Preferred Embodiment  
       [0049]     The embodiments of the present invention will be specifically explained.  
         [0050]      FIG. 3  is a vertical cross-sectional view of a speaker bracket and a speaker according to a first embodiment of the present invention.  FIG. 4  is a cross-sectional view of the state wherein the speaker in  FIG. 3  is attached to a speaker mounting portion.  FIG. 5  is a perspective view of the positional relationship between a speaker unit and the speaker bracket when the speaker in  FIG. 3  is to be packed. And  FIG. 6  is a vertical cross-sectional view of the packed state of the speaker in  FIG. 3 .  
         [0051]     A speaker  21  in this embodiment includes: a speaker unit  1 , formed by assembling a diaphragm  13  and a magnetic circuit  14 , which drives the diaphragm  13 , in a speaker frame  11  wherein cabinet mounting portions  11   a  are formed on a front end circumferential wall  11   b  and are to be fixed to a speaker mounting portion  23 , such as a cabinet; and a speaker bracket  25 , which is to be positioned between the front end circumferential wall  11   b  and the speaker mounting portion  23  when the speaker unit  1  is attached to the speaker mounting unit  23 , and serves as a fitting for the mounting size between the front end circumferential wall  11   b  and the speaker mounting portion  23 .  
         [0052]     For the speaker frame  11 , the front end circumferential wall  11   b , which is shaped almost like a ring, and a magnetic circuit supporting portion  11   c , which extends to the rear of the front end circumferential wall  11   b , are integrally formed while being cast. The inner front inner surface of the front end circumferential wall  11   b  serves as an edge supporting portion.  
         [0053]     In this embodiment, the cabinet mounting portions  11   a  respectively provide screw insertion portions  11   e  using a pair of facing claws lid and  11   d.    
         [0054]     The diaphragm  13  is a cone shaped object to which the outer edge of a roll edge  15  is bonded. The outer wall of the roll edge  15  is further securely adhered to the edge supporting portion of the front end circumferential wall  11   b.    
         [0055]     The speaker mounting portion  23  is formed, for example, using a baffle board  27  for a cabinet, and includes a speaker fitting hole  28 , into which the rear portion of the speaker unit  1  is to be inserted, and a plurality of screw fastening holes  29 , which are formed along a pitch circle surrounding the speaker fitting hole  28 .  
         [0056]     In this embodiment, the inner diameter of the speaker fitting hole  28  is larger than the outer diameter of the magnetic circuit supporting portion  11   c , and is slightly smaller than the standard diameter of a fitting hole for the speaker unit  1 . Also, the diameter of the speaker fitting hole  28  is smaller than the diameter of the pitch circle along which are arranged the fastening holes  29 , and the diameter of the pitch circle along which are arranged the screw insertion portions  11   e  of the front end circumferential wall  11   b  of the speaker frame  11 .  
         [0057]     That is, between the front end circumferential wall  11   b  of the speaker frame  11  and the speaker mounting portion  23  the mounting size does not match.  
         [0058]     As for the speaker bracket  25 , frame aligning portions  30 , which are to be fastened to the front end circumferential wall  11   b  of the speaker frame  11 , are provided on one face of a main body  25   a  shaped almost like a ring, and cabinet aligning portions  32 , which are to be fixed to the speaker mounting portion  23  that secures the front end circumferential wall  11   b , are provided on the other face of the main body  25   a.    
         [0059]     The frame aligning portions  30  respectively include: a ring-shaped horizontal contact face  30   a , which is used in common and which the front face or the rear face of the front end circumferential wall  11   b  contacts; vertical contact walls  30   b , which contact the outer face of the front end circumferential wall  11   b  and regulate movement along the horizontal contact face  30   a ; and fastening holes  30   c , which are formed in the horizontal contact face  30   a  in consonance with the screw insertion portions  11   e  of the cabinet mounting portions  11   a.    
         [0060]     As for the cabinet aligning portions  32 , in consonance with the fastening holes  29  of the speaker mounting portion  23 , fastening holes  32   b  are formed in protrusions  32   a  that are formed on the internal walls on one side of the main body  25   a.    
         [0061]     The cabinet aligning portions  32  are located at a plurality of positions on the inner wall of the main body  25   a , in consonance with the arrangement of the fastening holes  29  of the speaker mounting portion  23 .  
         [0062]     The obverse faces of the protrusions  32   a  on the speaker mounting portion  23  side are flattened, which permits them to be closely attached to the speaker mounting portion  23 .  
         [0063]     The same structure is employed for the front side and the side of the front end circumferential wall  11   b  of the speaker frame  11 .  
         [0064]     Therefore, as shown in FIGS.  4  to  6 , from the front and from the rear of the speaker frame  11 , the frame aligning portions  30  of the speaker bracket  25  can be fitted over the front end circumferential wall  11   b  of the speaker frame  11 .  
         [0065]     The size of the speaker bracket  25  in the axial direction is so designated that, as shown in  FIG. 6 , when the speaker bracket  25  is assembled with the front end circumferential wall  11   b  of the speaker frame  11  from the front of the speaker frame  11 , a protective gap S is provided between the protrusions  32   a  of the cabinet aligning portions  32  and the distal end of the roll edge  15  that is extended to the front of the speaker unit  1 , and thus, the protrusions  32   a  are extended forward of the roll edge  15  and the diaphragm  13 .  
         [0066]     In this case, the protective gap S is set to a value such that when the roll edge  15  or the diaphragm  13  is axially displaced, due, for example, to vibrations during delivery or transportation, the displacement will not adversely affect the speaker bracket  25 .  
         [0067]     When the speaker unit  1  is to be attached to the speaker mounting portion  23  of the baffle board  27 , as shown in  FIG. 4 , the speaker bracket  25  described above is employed by being assembled within the front end circumferential wall  11   b  of the speaker frame  11 , from the rear of the speaker frame  11 .  
         [0068]     For the assembly of the baffle board  27 , it is appropriate for the speaker bracket  25  to be attached to the baffle board  27 , and then, for the speaker unit  1  to be fitted to the speaker bracket  25 .  
         [0069]     For packaging the speaker unit  1 , as shown in  FIG. 5 , the speaker bracket  25  is fitted on the front end circumferential wall  11   b , from the front of the speaker unit  1 , so that the frame aligning portions  30  of the speaker bracket  25  are located opposite the cabinet mounting portions  11   a  of the front end circumferential wall  11   b.    
         [0070]     When the cabinet mounting portions  11   a  and the frame aligning portions  30   a  refastened together by screws, the speaker bracket  25  can be securely fixed to the front race of the speaker unit  1 .  
         [0071]     When the packaging is completed, the speaker  21  of this embodiment is held using packaging components, while, as shown in  FIG. 5 , the speaker bracket  25  has been fitted to the front end circumferential wall  11   b , from the front of the speaker frame  11 .  
         [0072]     In the state shown in  FIG. 6 , the speaker  21 , to be accommodated with packaging in a box (not shown), is held using packaging components  35  and  36  made, for example, of Styrofoam.  
         [0073]     The packaging component  35  is so designed that a step portion  35   b , which the rear end face of the front end circumferential wall  11   b  contacts, is formed around a recessed portion  35   a  in which the rear portion of the speaker unit  1  is to be accommodated. In this embodiment, a depth d of the step portion  35   b  is slightly larger than a value obtained by adding a thickness d 1  for the front end circumferential wall  11   b  to a thickness d 2  for the speaker bracket  25  that overlaps the front end circumferential wall  11   b . As the depth d of the step portion  35   b  is nearer (d 1 +d 2 ), the speaker  21  can be held more accurately.  
         [0074]     The packaging component  36  is a member used to cover the packaging component  35 . When the front end circumferential wall  11   b  and the speaker bracket  25  are sandwiched between the packaging component  36  and the step portion  35   b  of the packaging component  35 , the speaker unit  1  is prevented from popping out of the recessed portions  35   a  due to shaking or to a shock received during delivery.  
         [0075]     According to the speaker  21  of the first embodiment, during the packaging process, the speaker bracket  25  connected to the speaker unit  1  is attached to the front end circumferential wall  11   b  of the speaker frame  11 , from the front of the speaker unit  1 . Thus, the speaker bracket  25  serves as a protective cover that establishes the protective gap S in front of the diaphragm  13  of the speaker unit  1 , and covers the front face of the speaker.  
         [0076]     Sequentially, when the speaker  21  is packed in a state wherein the speaker bracket  25  has been attached to the front end circumferential wall  11   b  of the speaker frame  11  from the front of the speaker unit  1 , as shown in  FIG. 6 , a projected portion  36   a  of the packaging component  36 , which prevents the speaker unit  1  from popping out to the front, holds the face of the speaker bracket  25  on which the cabinet aligning portions  32  are formed, without directly contacting the front end circumferential wall  11   b  of the speaker frame  11 . Therefore, when a length L of the projected portion  36   a  is increased toward the center axis of the speaker  21 , the projected portion  36   a  does not adversely affect the roll edge  15  that is projected outward, from inside the front end circumferential wall  11   b , to the front of the speaker  21 , and a large contact area is still available for holding the speaker  21 .  
         [0077]     Therefore, if the box used for the packaging is dropped, the shear force exerted by the speaker unit  1  on the projected portion  36   a  of the packaging component  36  can be received by and distributed across a large contact area, and the destruction or deformation of the projected portion  36   a  can be prevented. Therefore, the speaker unit  1  can be immobilized, and can be protected from damage.  
         [0078]     Since the speaker bracket  25 , which originally is located between the speaker unit  1  and the speaker mounting portion  23  in order to adjust the mounting size, is assembled, from the front, with the front end circumferential wall  11   b  of the speaker frame  11 , the speaker bracket  25  serves as a protective cover that protects the front face of the speaker unit  1 , and protection for the speaker unit  1  is reinforced. Thus, an additional packaging component is not especially required to provide reinforced protection.  
         [0079]     Therefore, the packaging structure is prevented from becoming complicated due to an increase in the packaging components, a box for packaging can be easily designed because the packaging structure is simplified, and manufacturing costs can be reduced.  
       The Second Preferred Embodiment  
       [0080]     FIGS.  7  to  13  are diagrams showing a speaker bracket and speaker according to a second embodiment of the present invention.  FIG. 7  is an exploded perspective view of a case wherein the speaker of the second embodiment is to be attached to a speaker mounting portion.  FIG. 8  is a front view of the speaker bracket shown in  FIG. 7 .  FIG. 9  is a rear view of the speaker bracket shown in  FIG. 7 .  FIG. 10  is a cross-sectional view taken along A-A in  FIG. 8 .  FIG. 11  is a diagram of the speaker bracket in  FIG. 8 , viewed from a direction indicated by an arrow B.  FIG. 12  is a cross-sectional view taken along C-C in  FIG. 9 . And  FIG. 13  is an enlarged diagram showing a portion D in  FIG. 8 .  
         [0081]     According to a speaker  41  for the second embodiment, a speaker mounting portion  43 , formed of a baffle board  42 , includes: an elliptical speaker fitting hole  44  and a plurality of fastening holes  45 , formed around the speaker fitting hole  44 . Therefore, a speaker bracket  46 , the inner circumference of which is substantially formed perfectly circular and the outer circumference of which is elliptical, is connected to a speaker unit  1 , the outer circumference of which is substantially a perfect circle, and the speaker unit  1  can be attached to the speaker mounting portion  43 .  
         [0082]     Since the structure of the speaker unit  1  is the same as that for the first embodiment, no further explanation for it will be given.  
         [0083]     The smaller diameter of the elliptical speaker fastening hole  44  is almost equal to, or greater than the outer diameter of a front end circumferential wall  11   b.    
         [0084]     For the speaker bracket  46  of this embodiment, frame aligning portions  47 , which are to be fastened to the front end circumferential wall  11   b  of a speaker frame  11 , are formed on one face of a bracket main body  46   a , the inner circumference of which is almost perfectly circular and the outer circumference of which is elliptical. On the other face of the bracket main body  46   a , cabinet aligning portions  48 ,  49  and  50  are formed that are to be fixed to the speaker mounting portion  43  that secures the front end circumferential wall  11   b . When the speaker unit  1  is to be attached to the speaker mounting portion  43 , these cabinet aligning portions  48 ,  49  and  50  are used to adjust the mounting size between the front end circumferential wall  11   b  and the speaker mounting portion  43 .  
         [0085]     As shown in  FIGS. 7 and 8 , the obverse side of the bracket main body  46   a  is simply a flat face. On the other hand, as shown in  FIG. 9 , on the rear face of the bracket main body  46   a , ribs  46   d  are radially formed to connect an inner vertical wall  46   b , which serves as an inner perfectly circular portion, to an outer vertical wall  46   c , which serves as an outer elliptical portion, in order to provide additional strength while reducing the weight.  
         [0086]     The outer diameter of the bracket main body  46   a  is so set that it is larger than the diameter of the speaker fitting hole  44 , to ensure that the outer circumferential portion overlaps the edge of the speaker fitting hole  44 .  
         [0087]     As shown in  FIG. 8 , the frame aligning portions  47  respectively include: a ring-shaped horizontal contact face  47   a , which is used in common and which the front face or the rear face of the front end circumferential wall  11   b  contacts; vertical contact walls  47   b , which contact the outer face of the front end circumferential wall  11   b  and regulate movement along the horizontal contact face  47   a ; and fastening holes  47   c , which are formed in the horizontal contact face  47   a  in consonance with screw insertion portions  11   e  of cabinet mounting portions  11   a.    
         [0088]     The fastening holes  47   c  are located in consonance with those of the screw insertion portions  11   e  of the cabinet mounting portions  11   a.    
         [0089]     The cabinet aligning portions  48  and  49  are respectively screw holes and notches, which are bored through from one face to the other of the bracket main body  46   a , in consonance with the fastening holes  45  of the speaker mounting portion  43 .  
         [0090]     The cabinet aligning portions  48  are simple elliptical holes in cross section. On the other hand, as shown in  FIG. 13 , the cabinet aligning portions  49  are notches, having a deformed structure in cross section, such that a circular hole  49   b  is connected to an elliptical hole  49   a  at the eccentric position of the elliptical hole  49   a . This is based on the consideration that only screws at the cabinet aligning portions  48  need be removed, and screws at the cabinet aligning portions  49  may simply be loosened, so that the speaker bracket  46  can be easily removed from the speaker mounting portion  43 .  
         [0091]     The cabinet aligning portions  50  are spare screw holes used when the arrangement of the fastening holes  45  of the speaker mounting portion  43  is changed again.  
         [0092]     Also for the speaker bracket  46  in the second embodiment, the frame aligning portions  47  can be attached to the front end circumferential wall  11   b , from the front and from the rear of the speaker frame  11 .  
         [0093]     In this embodiment, as in the first embodiment, when packing is completed, the speaker  41  is held by using packing components in a state wherein the speaker bracket  46  has been attached to the front end circumferential wall  11   b , from the front of the speaker frame  11 .  
         [0094]     As a result, the same operating effects as in the first embodiment can be obtained.  
         [0095]     As described above in detail, according to this embodiment of the invention, provided is the speaker bracket  25 , which is formed almost like a ring, on one face of which are provided the frame aligning portions  30  to be fastened to the front end circumferential wall  11   b  of the speaker frame  11 , and on the other face of which are provided the cabinet aligning portions  32  to be fixed to the speaker mounting portion  23  of the cabinet that secures the front end circumferential wall  11   b , and which is employed to match the mounting size between the front end circumferential wall  11   b  and the speaker mounting portion  23  when the speaker unit  1  is attached to the speaker mounting portion  23 , wherein the frame aligning portions  30  are formed so as to be attachable from the front end circumferential wall  11   b , from the front and from the rear of the speaker frame  11 .  
         [0096]     According to the above arrangement, during the packaging process, the speaker bracket  25  is attached, from the front of the speaker unit  1 , to the front end circumferential wall  11   b  of the speaker frame  11  and to the speaker unit  1 . As a result, the speaker bracket  25  serves as a protective cover that encloses the front face of the speaker, while providing the protective gap S in front of the diaphragm  13  of the speaker unit  1 .  
         [0097]     As described above in detail, the speaker  21  according to this embodiment includes: the speaker unit  1 , formed by assembling the diaphragm  13  and the magnetic circuit  14 , for driving the diaphragm  13 , with the speaker frame  11  in which the cabinet mounting portions  11   a  are formed on the front end circumferential wall  11   b  and are to be fixed to the speaker mounting portion  23  of a cabinet; and the speaker bracket  25 , positioned between the front end circumferential wall  11   b  and the speaker mounting portion  23  for attachment of the speaker unit  1  to the speaker mounting portion  23 , and used for matching a mounting size between the front end circumferential wall  11   b  and the speaker mounting portion  23 , wherein the speaker bracket  25  of this embodiment is employed as the speaker bracket  25 .  
         [0098]     Therefore, when the speaker  21  is packed in a state wherein the speaker bracket  25  has been attached, from the front of the speaker unit  1 , to the front end circumferential wall  11   b  of the speaker frame  11 , the projected portion  36   a  of the packaging component  36 , which prevents the speaker unit  1  from popping out to the front, does not directly contact the front end circumferential wall  11   b  of the speaker frame  11 , and holds the other face of the speaker bracket  25  that includes the cabinet aligning portions  32 . Therefore, when the length of the projected portion  36   a  is increased toward the center axis of the speaker  21 , the projected portion  36   a  does not adversely affect the roll edge  15  that projects outward, from inside the front end circumferential wall  11   b , to a position forward of the speaker  21 . Thus, a large contact area is provided for the projected portion  36   a  that holds the speaker bracket  25 .  
         [0099]     Therefore, if a box in which the speaker unit  1  is packaged is dropped, the shear force imposed on the projected portion  36   a  of the packaging component  36  by the speaker unit  1  is received by and distributed across a large contact area, and the destruction or deformation of the projected portion  36   a  can be prevented. Thus, the speaker unit  1  can be immobilized and protected from damage.  
         [0100]     In this invention, the speaker bracket  25 , which originally is located between the speaker unit  1  and the speaker mounting portion  23  to adjust a mounting size, is attached to the front end circumferential wall  11   b  from the front of the speaker frame  11 . Thus, the speaker bracket  25  functions as a protective cover for the front cover of the speaker unit  1 , and since it also provides reinforced protection for the speaker unit  1 , eliminates the need for an additional packaging component that would furnish such reinforcement.  
         [0101]     Therefore, the packaging structure is simplified and prevented from becoming complicated, due to an increase in the packaging components, so that a box for packaging can be easily designed and manufacturing costs can be reduced.