Abstract:
A speaker apparatus that even when being relatively thin and compact, realizes reduction of generation of abnormal noise by contact between a lead wire and another member, reduction of breakage of lead wire and reduction of deterioration of sound quality. The speaker apparatus is one comprising magnetic circuit ( 2 ) provided with a magnetic gap in which voice coil ( 33 ) is fitted with play; vibrator ( 3 ) directly or indirectly fixed to the voice coil ( 33 ); frame ( 5 ) supporting the vibrator ( 3 ), provided thereinside with the magnetic circuit ( 2 ); and terminal part ( 6 ) to which lead wire ( 4 ) from the voice coil ( 33 ) is connected, wherein lead path ( 7 ) for passage of the lead wire ( 4 ) coming from the voice coil ( 33 ) is disposed between the voice coil ( 33 ) fitted with play in the magnetic gap (G) and the terminal part ( 6 ) provided in the frame ( 5 ).

Description:
FIELD OF INVENTION 
       [0001]    The invention is related to a speaker device. 
       BACKGROUND OF THE INVENTION 
       [0002]    In a general speaker device, a voice coil fixed to a diaphragm is arranged to vibrate vibratably in a magnetic gap of a magnetic circuit. A lead wire pulled out of the voice coil is fixed and electrically connected to a terminal part provided on a speaker frame. For example, a general speaker device possesses the structure that the lead wire is connected to the terminal part not in a straight line, but connected with some extra length portions such as bent portions, etc. (for example, see Japanese Patent Publication 2003-348690). In the above speaker device, the lead wire is adaptable to the displacement of the voice coil and the stress applied to the lead wire is reduced by the bent portions of the lead wire. 
       DISCLOSURE OF THE INVENTION 
       [0003]    However, for a thin speaker device or small speaker device, the space for the lead wire of the voice coil is limited such that the extra length portions can contact the magnetic circuit, the diaphragm and the edge part, etc., thereby making abnormal noise, or otherwise causing breakage of the lead wire due to the stress applied to the connecting part between the lead wire and the terminal part. 
         [0004]    Further, for a thin speaker device or small speaker device, the configuration (pathway) of the lead wire between the voice coil and the terminal part has a large affect on the weight balance of the voice coil. If the weight balance is poor, unwanted vibrations occur, causing the deterioration of acoustic quality. 
         [0005]    According to one aspect of the present invention, a speaker device includes a magnetic circuit having a magnetic gap where a voice coil freely fits, a vibrating body bonded directly or indirectly to the voice coil, a frame for supporting the vibrating body and housing the magnetic circuit, and a terminal part to which the lead wire of the voice coil is connected. A passage through which the lead wire pulled out of the voice coil is arranged between the voice coil freely fitted in the magnetic gap and the terminal part provided in proximity of the frame. The lead wire is configured to be in a bent shape substantially point-symmetrically with respect to the center of the voice coil in the passage. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  is a plan view of a speaker device  1  according to a first embodiment of the present invention; 
           [0007]      FIG. 2(A)  is a sectional view of the speaker device  1  viewed from a viewing direction D 1  shown in  FIG. 1 , and  FIG. 2(B)  is a sectional view of the speaker device  1  viewed from a viewing direction D 2  in  FIG. 1 ; 
           [0008]      FIG. 3  is a plan view of the speaker device  1 A according to a second embodiment of the present invention; 
           [0009]      FIG. 4  is a plan view of the speaker device  1 B according to a third embodiment of the present invention; 
           [0010]      FIG. 5  is a sectional view of the speaker device  1 B viewed from a viewing direction D 1  shown in  FIG. 4 ; 
           [0011]      FIG. 6  is a plan view of the speaker device  1 C according to a fourth embodiment of the present invention; 
           [0012]      FIG. 7  is a sectional view of the speaker device  1 C shown in  FIG. 6 ; 
           [0013]      FIG. 8  is an enlarged sectional view around a lead wire  4  of the speaker device  1 C shown in  FIG. 7 ; 
           [0014]      FIG. 9  is an exploded perspective view of the magnetic circuit  2 C of the speaker device  1 C shown in  FIG. 6 ; 
           [0015]      FIG. 10(A)  is a side view of a passage through which the lead wire of the speaker device may be pulled according to the first embodiment of the present invention,  FIG. 10(B)  is a side view of a passage through which the lead wire of the speaker device may be pulled according to the second embodiment of the present invention; 
           [0016]      FIG. 11(A)  is a front view of the speaker device according to one embodiment of the present invention, illustrating a voice coil  33 D,  FIG. 11(B)  is an enlarged view around a winding start point of the conductive wire  401  of the voice coil shown in  FIG. 11(A) ,  FIG. 11(C)  is an enlarged view around a winding end point of the conductive wire  401  of the voice coil shown in  FIG. 11(A) ,  FIG. 11(D)  is a view of a voice coil modified from the voice coil shown in (B), and  FIG. 11(E)  is a view of a voice coil modified from the voice coil shown in  FIG. 11(C) ; 
           [0017]      FIG. 12  is a plan view of the speaker device  1 F according to a fifth embodiment of the present invention; and 
           [0018]      FIG. 13  is a plan view of the speaker device  1 G according to a sixth embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]    The speaker device according to a embodiment of the present invention, includes a magnetic circuit having a magnetic gap where a voice coil freely fits, a vibrating body bonded directly or indirectly to the voice coil, a frame for supporting the vibrating body and housing the magnetic circuit, and a terminal part to which the lead wire of the voice coil is connected, wherein a passage is arranged through which the lead wire may be pulled out of the voice coil between the voice coil which is freely fitted in the magnetic gap and the terminal part provided in proximity of the frame. 
         [0020]    According to the speaker device as structured above, the magnetic circuit has a passage through which the lead wire may pass between the voice coil which is freely fitted in a magnetic gap and the terminal part provided in proximity of a frame such that the lead wire of the voice coil can be electrically connected through this passage to the terminal part provided in proximity of the frame. Therefore, the lead wire can be prevented from contacting, for example the magnetic circuit, the diaphragm and the edge part, thus reducing the generation of abnormal noise. Further, a thin speaker device or a small speaker device with high acoustic quality can be produced. In addition, as the lead wire can be prevented from contacting other member, breakage of the lead wire due to such contact can be prevented. 
         [0021]    Hereinafter, a speaker device according to one embodiment of the present invention is described with reference to the drawings. 
       First Embodiment 
       [0022]      FIG. 1  is a plan view of a speaker device  1  according to a first embodiment of the present invention.  FIG. 2(A)  is a sectional view of the speaker device  1  viewed from a viewing direction D 1  shown in  FIG. 1  and  FIG. 2(B)  is a sectional view of the speaker device  1  viewed from a viewing direction D 2  in  FIG. 1 . The diaphragm and edge of a speaker device are not shown in  FIG. 1 . 
         [0023]    The speaker device  1  according to this embodiment is thin and small as shown in  FIG. 1 . Further, the speaker device  1  according to this embodiment is adopted for a mobile phone, an earphone, etc. 
         [0024]    The speaker device  1  according to this embodiment includes a magnetic circuit  2 , a vibrating body  3 , a voice coil  33 , a lead wire  4 , a frame  5 , and a terminal part  6 . The magnetic circuit  2  has a passage  7  through which the lead wire  4  of the voice coil  33  may be pulled. 
         [0025]    A magnetic circuit  2  corresponds to a magnetic circuit according to one embodiment of the present invention; a vibrating body  3  corresponds to a vibrating body according to one embodiment of the present invention; a frame  5  corresponds to a frame according to one embodiment of the present invention. A voice coil  33  corresponds to a voice coil according to one embodiment of the present invention; a lead wire  4  corresponds to a lead wire according to one embodiment of the present invention; and a terminal part  6  corresponds to a terminal part according to one embodiment of the present invention. A passage  7  corresponds to a passage according to one embodiment of the present invention. 
         [0026]    For example, inner-magnet-type magnetic circuit and an outer-magnet-type magnetic circuit can be adopted as the magnetic circuit  2 . The inner-magnet-type magnetic circuit is adopted for the present embodiment. The magnetic circuit  2  has a magnetic gap G where the voice coil  33  freely fits. 
         [0027]    Specifically, the magnetic circuit  2  according to this embodiment includes a yoke  21 , a magnet  22  and a plate  23 . The yoke  21  has a bottom portion  21 A, a bent portion  21 B and a side portion  21 C. The bottom portion  21 A of the yoke  21  has a substantially round plate, a bent portion  21 B of the yoke  21  is bent from the bottom portion  21 A of the yoke  21  to the acoustic wave emitting direction (SD), and a cylindrical side portion  21 C of the yoke  21  extends from the bent portion  21 B to the acoustic wave emitting direction as shown in  FIGS. 1 and 2 . Further, the yoke  21  has a cross-section shape formed substantially in a U shape, as shown in  FIG. 2 . The bottom portion  21 A, the bent portion  21 B and the side portion  21 C of the yoke  21  are integrally formed using a known material such as an iron. 
         [0028]    Further, the yoke  21  has a cutout  71  formed in the side portion  21 C. The cutout  71  corresponds to one embodiment of the passage  7 . The passage  7  is provided between the voice coil  33  which is freely fitted in the magnetic gap G, and the terminal part  6  provided at the frame  5 . Further, the cutout  71  is formed near the pull-out position of the voice coil  33 , as shown in  FIG. 1 . The cutout  71  according to this embodiment is formed substantially symmetrically with respect to the center axis of the voice coil  33  and located at a predetermined interval. The yoke  21  according to this embodiment has a substantially U-shaped cutout  71  with a predetermined length, formed from the upper end portion  21 D to the bottom portion  21 A of the yoke  21  as shown in  FIG. 2(A)  or  FIG. 2(B) . The lead wire  4  pulled out of the voice coil  33  is connected through the cutout  7  to the terminal part  6  provided in proximity of the frame  5 . For example, the lead wire  4  is connected to the terminal part  6  by soldering, or thermo-compression, etc. 
         [0029]    The lead wire  4  is arranged at a predetermined distance from the cutouts  71 . Specifically, the configuration of the lead wire  4  and the cutout  71  of the passages  7 , the location of the terminal part  6  with respect to the location of the cutout  71 , and the location of the support member  51  with respect to the location of the cutout  71  are adapted such that the lead wire  4  does not contact with at least yoke  21 , frame  5 , edge  32  and cutout  71  even when the voice coil vibrates, for example in a vertical direction (acoustic wave emitting direction). 
         [0030]    The magnet  22  is made of a permanent magnet such as a neodymium magnet, a samarium-cobalt magnet, an alnico magnet, and a ferrite magnet. The magnet  22  is located on the bottom portion  21 A of the yoke  21  as shown in  FIG. 2(A) . The magnet  22  according to the present embodiment is formed in a columnar shape. 
         [0031]    The plate  23  is made up of a predetermined material such as iron and located on the magnet  22  as shown in  FIG. 2(A) . The plate  23  is formed, for example round and in a plate shape. 
         [0032]    The magnetic circuit  2  as structured above has a magnetic gap G formed annularly circumferentially between the yoke  21  and the plate  23 . 
         [0033]    The vibrating body  3  is bonded to the voice coil  33  directly or indirectly through a member such as that of a voice coil bobbin. The vibrating body  3  according to this embodiment has the diaphragm  31  and edge  32  as shown in  FIGS. 1 and 2 . 
         [0034]    The diaphragm  31  is formed in a predetermined shape, for example in a flat plate shape, dome shape, and cone shape. The diaphragm  31  is fixed to the frame  5  vibratably through edge  32 . Specifically, the outer periphery of the diaphragm  31  is bonded to the inner periphery of the edge  32  with adhesive. The diaphragm  31  of this embodiment is formed round and in a plate shape. The upper end portion of the voice coil  33  is bonded to the surface of the diaphragm  31  opposite to the acoustic wave emitting side, for example with adhesive. The diaphragm  31  is made of a known material, for example a metal material such as aluminum, titanium and beryllium, a resin material such as polyarylate, polyimide, and polyethylene naphthalate, a plastic, a paper, a reinforced plastic fiber or a ceramic material. 
         [0035]    The outer periphery of the edge  32  is fixed to the upper end portion  5 A of the frame  5  with adhesive while its inner periphery is bonded to the outer periphery of the diaphragm  31 , supporting the diaphragm  31  vibratably. The cross-section shape of the edge  32  is formed in a predetermined shape such as convex, U-shape, V-shape, wavelike shape, corrugated shape, or plate shape in an acoustic wave emitting direction. The cross-section shape of the edge  32  is formed in a U-shape (concave) in an acoustic wave emitting direction. 
         [0036]    The diaphragm  31  and the edge  32  can be integrally formed using a similar material such as resin. 
         [0037]    The voice coil  33  is formed in a ring shape as shown in  FIGS. 1 and 2 . The voice coil  33  is formed by winding a conductive wire. The voice coil  33  is formed in a shape corresponding to that of the magnetic gap G of the magnetic circuit  2 . The voice coil  33  according to this embodiment has a cylindrical shape. 
         [0038]    The lead wire  4  pulled out of the voice coil  33  is connected through the passage  7  to the terminal part  6  provided in proximity of the frame  5  as shown in  FIGS. 2(A) and 2(B) . Further, the lead wire  4  has an extra length portion  41  in a bent shape between the passage  7  and the terminal part  6 . The extra length portion  41  of the lead wire  4  is adapted to go around a part of the yoke  21  of the magnetic circuit  2 . 
         [0039]    The lead wire  4  is pulled out of the lower end portion of the voice coil  33 , extends through the passage  7  to the inner periphery of the frame  5 , bends near the inner periphery of the frame  5  toward the terminal part  6 , and further extends in an arc from the bent portion  42  to the terminal part  6  along the inner periphery of the frame  5 , thus being electrically connected and fixed to the terminal part  6 . 
         [0040]    More specifically, the lead wire  4  extends from the pull-out position of the voice coil  33  through the passage  7  in the radial and outside direction, bends approximately at 90 to 160 degrees with respect to the extending direction substantially in a direction toward the periphery of the voice coil, then further extends from the bent portion  42  to the terminal part  6  formed at a radially predetermined distance from the voice coil  33  such that an extra length portion  41  is formed in a predetermined length along the periphery of the voice coil  33 . 
         [0041]    A pair of the lead wires  4  is pulled out of the voice coil  33  as shown in  FIG. 1 . The pair of the lead wires  4  are configured substantially symmetrically with respect to the center of the voice coil  33 . The configuration (pathway) of the lead wire  4  between the voice coil  33  and the terminal part  6  has a large affect on the weight balance of the voice coil  33 . However, since the pair of the lead wires described above are configured substantially symmetrically with respect to the center of the voice coil  33 , a bearing power of the pair of the lead wires are generated for the voice coil  33  to keep a balance, thus reducing unwanted vibration of the voice coil  33 . In other words, the pair of the lead wires  4  are arranged substantially symmetrically to each other such that the weight balance of the voice coil or the vibrating body is maintained to a maximum extent. 
         [0042]    Further, the lead wire  4  is also configured to maintain the balance of the voice coil  33  corresponding to the displacement of the gravity center of the voice coil  33  due to the winding of a conductive wire of the voice coil  33  from a winding start point through a winding end point. 
         [0043]    Further, the lead wire  4  is configured such that the extra length portion  41  is located between the edge  32  and frame  5 . 
         [0044]    The lead wire  4  pulled out of the voice coil  33  has a plurality of bent portions. Having a plurality of bent portions, the lead wire  4  has the large bearing power and can support the voice coil  33  without generating abnormal vibration such as the rolling phenomenon. Also, the balance of the voice coil  33  is maintained. Further, the lead wire  4  having a predetermined rigidity or elasticity and the bent portions supports the voice coil  33  so as to prevent from the rolling vibration, for example. 
         [0045]    The frame  5  supports the vibrating body  3  and houses the magnetic circuit  2 . The frame  5  according to this embodiment has a section formed in a U-shape. The magnetic circuit  2  is arranged on a planar base portion  5 B. Further, the frame  5  has a side portion  5 C extending from the base portion  5 B in an acoustic wave emitting direction. The upper end portion  5 A of the side portion  5 C is bonded to the outer periphery of the edge  32  thereto with adhesive or the like. The frame  5  is made of a predetermined material, such as resin. 
         [0046]    The frame  5  has a support member  51  located between the passage  7  of the magnetic circuit  2  and the terminal part  6 . The support member  51  is formed as a protrusion in a predetermined position of the frame  5  to contact and support the lead wire  4 . The support member  51  can reduce the vibration or stress that is conducted from the voice coil  33  to the terminal part  6  through the lead wire  4 . The support member  51  is formed on the outer periphery side of the extra length portion of the lead wire  4 , contacting and supporting the lead wire  4  as shown in  FIG. 1 . 
         [0047]    The terminal part  6  is formed in a predetermined position of the frame  5 , having the end of the lead wire  4  pulled out of the voice coil  33  electrically connected thereto. A metal with a high electrical conductivity such as iron can be used for the terminal part  6 . The terminal part  6  is formed in a position where the extra length portion  41  of the lead wire  4  is arranged between the passage  7  of the magnetic circuit  2  and the terminal part  6  as shown in  FIGS. 1 and 2 . Specifically, a pair of the terminal parts  6  is formed at a predetermined distance annularly from the two cutouts  71  formed at the yoke  21  through which the lead wire  4  passes as shown in  FIG. 1 . Further, the pair of the terminal parts  6  are formed substantially symmetrically with respect to the center axis of the voice coil  33 . 
         [0048]    More specifically, the terminal part  6  has an inner terminal part  61  and an outer terminal part  62  as shown in  FIGS. 1 and 2 . The inner terminal part  61  and the outer terminal part  62  are electrically connected to each other. The inner terminal part  61  is formed as a protrusion from the inner periphery of the frame  5 , while the outer terminal part  62  is formed as a protrusion from the outer periphery of the frame  5 . The outer terminal part  62  may be a protrusion from the base portion of the frame  5 . The outer terminal part  62  can be electrically connected to the terminal part of an external circuit such as a sound signal processing circuit. 
         [0049]    More specifically, the lead wire  4  extends from a lower end portion of the voice coil  33  near the cutout  71 , or the passage  7 , through the cutout  71  of the passage  7  toward substantially radially outside, and bends substantially in an annular direction (counterclockwise with reference to acoustic wave emitting direction), while the positions of the terminal part  6  and the support member  51  are configured such that the extra length portion  41  is formed in a predetermined length. 
         [0050]    Hereinafter, the operation of the speaker device  1  as structured above is described with reference to the drawing. According to the speaker device  1 , a sound signal is inputted from the terminal part  6  and inputted into the voice coil  33  through the lead wire  4  electrically connected to the inner terminal part  61  of the terminal part  6 . An electromagnetic force is generated in the vertical direction (an acoustic wave emitting direction or its opposite direction) in accordance with a magnetic flux density (magnetic field intensity) formed in the magnetic gap G of the magnetic circuit  2  and a current level of the sound signal inputted into the voice coil  33 . The voice coil  33  is driven by the electromagnetic force and vibrates in an acoustic wave emitting direction or its opposite direction. 
         [0051]    When the driving force is transmitted to the diaphragm  31  through the voice coil  33 , the vibrating body  3  vibrates in an acoustic wave emitting direction or its opposite direction in accordance with the driving force. The lead wire  4  of the voice coil  33  passes through the cutout  71  of the passage  7 , formed in the yoke  21 , goes around a part of the side portion  21 C of the yoke  21 , and connects to the terminal part  6  with the extra length portion as described above. Therefore, the lead wire  4  is displaced following the vibration of the voice coil  33 . 
         [0052]    According to the speaker device  1  having the thin and small magnetic circuit  2 , the vibrating body  3  and the frame  5 , etc., the lead wire  4  being connected to the terminal part  6  with the extra length portion after passing through the passage  7  can be prevented from contacting other member such as the yoke  21  and the edge  32  when the voice coil  33  is displaced in a vertical direction. 
         [0053]    Specifically, if the lead wire  4  pulled out of the voice coil  33  passes through simply between the upper end portion of the yoke  21  and the edge  32  to connect to the terminal part  6  with reference to  FIG. 2 , there is a possibility that the lead wire  4  contacts the edge  32 , because the interval between the upper end portion of the yoke  21  and the edge  32  is narrow. On the other hand, in the speaker device  1  according to the present invention, the passage  7  through which the lead wire  4  passes being provided in proximity of the magnetic circuit  2  as described above, the contact between the lead wire  4  and the edge  32  can be prevented even when the interval between the upper end portion of the yoke  21  and edge  32  is narrow. 
         [0054]    In addition, the speaker device  1  can reduce a generation of abnormal noise caused by such the contact. In other words, a thin and/or small speaker device with high acoustic quality can be produced. 
         [0055]    Furthermore, the speaker device  1  can prevent from the breakage of the lead wire  4  caused by the contact between the lead wire  4  and other member as described above. 
         [0056]    Furthermore, the cutout  71  of the passage  7 , being configured substantially symmetrically with respect to the center axis of the voice coil  33  at a predetermined distance as shown in  FIG. 1 . A pair of the lead wires  4  being configured substantially symmetrically with respect to the center point of the voice coil  33 , the balance of the voice coil  33  can be maintained to reduce unwanted vibration of the voice coil  33 . Therefore, the speaker device  1  can be produced with high quality. 
       Second Embodiment 
       [0057]      FIG. 3  is a plane view of the speaker device  1 A according to a second embodiment of the present invention. The same configurations as the first embodiment are not repeatedly described. In a speaker device  1 A according to the present embodiment, the support member  51 A disposed between the voice coil  33  and the terminal part  6  is formed near the cutout  71 , or the passage  7 , compared to the first embodiment. Further the support member  51 A is located in the inner periphery side of the bent portion  42  of the lead wire  4 . 
         [0058]    The bent portion  42  of the lead wire  4  can be easily formed, as the support member  51 A is formed near the cutout  71 , or the passage  7 , and located in the inner periphery side of the bent portion  42  of the lead wire  4 , according to the above speaker device  1 A. Specifically, the lead wire  4  is originally pulled out of the voice coil  33  in a straight line. When freely fitting the voice coil  33  in the magnetic gap G of the magnetic circuit  2 , the lead wire  4  in the above described form can be easily obtained by bending the lead wire  4  pulled out of the voice coil  33  around the support member  51 A to form the bent portion  42 , then connecting the end of the lead wire  4  to the terminal part  6 . 
       Third Embodiment 
       [0059]      FIG. 4  is a plane view of the speaker device  1 B according to a third embodiment of the present invention, where any diaphragm or the edge is not shown.  FIG. 5  is a cross-sectional view of the speaker device  1 B viewed from a viewing direction D 1  shown in  FIG. 4 . The same configurations as the first and second embodiments are not repeatedly described. 
         [0060]    The speaker device  1 B according to the present embodiment has a first support member  51  and a second support member  52 , as shown in  FIGS. 4 and 5 . The first support member  51  is the similar constituent element as the support member  51  of the first embodiment. 
         [0061]    The second support member  52  is formed in substantially the same position as the support member  51 A according to the second embodiment, having substantially the similar function as the support member  51  A. The second support member  52  according to the present embodiment is formed in a reverse L-shape as shown in  FIG. 5 . 
         [0062]    In the speaker device  1 B as structured above including support member  52  in the reverse L-shape and support member  51 , a stress is prevented from being applied to a connecting portion to the terminal part  6  while the lead wire  4  is prevented from being disconnected with the terminal part even when the lead wire  4  vibrates during a speaker is driven. 
       Fourth Embodiment 
       [0063]      FIG. 6  is a plane view of the speaker device  1 C according to a fourth embodiment of the present invention.  FIG. 7  is a cross-sectional view of the speaker device  1 C shown in  FIG. 6 .  FIG. 8  is an enlarged cross-sectional view around a lead wire  4  of the speaker device  1 C shown in  FIG. 7 .  FIG. 9  is an exploded perspective view of the magnetic circuit  2 C of the speaker device  1 C shown in  FIG. 6 . The diaphragm and the edge of the speaker device  1 C are not shown in  FIG. 6 . The same configurations as those in the first to third embodiments are not repeatedly described. 
         [0064]    The speaker device  1 C according to the present embodiment has a magnetic circuit  2 C, a voice coil  33 C and a frame  5  as shown in  FIG. 6 . 
         [0065]    The magnetic circuit  2 C according to the present embodiment is formed substantially in a rectangular shape when viewed in the acoustic wave emitting direction as shown in  FIGS. 6 and 9 . The magnetic circuit  2 C has a substantially rectangular bottom portion  21 A, a bent portion  21 B bent toward the acoustic wave emitting direction from the bottom portion  21 A, and a side portion  21 C extending toward the acoustic wave emitting direction from the bent portion  21 B. The magnetic circuit  2 C according to the present embodiment has the passage  7  formed in a corner of the substantially rectangular shape. Specifically, the yoke  21  has four corners and the cutout  71  is formed in the each corner of the four corners. The passage  7  through which the lead wire  4  passes is formed in at least two opposing corners of the four corners of the yoke  21  as shown in  FIG. 6 . 
         [0066]    The voice coil  33 C is formed substantially in a rectangular shape when viewed in the acoustic wave emitting direction, having a straight portion  331  and a curved portion  332  as shown in  FIG. 6 . The voice coil  33 C is freely fitted in the magnetic gap G of the magnetic circuit  2 . The lead wire  4  pulled out of the voice coil  33 C is pulled out of the straight portion  331  to reduce a stress applied to the pull-out portion. 
         [0067]    The frame  5  has a terminal part  6 C formed near the corner where the passages  7  of the magnetic circuit  2  are not configured as shown in  FIG. 6 . Specifically, the terminal part  6 C has an inner terminal part  61  formed inside of the frame and an outer terminal part  62  formed outside of the frame, the inner terminal part  61  and the outer terminal part  62  being electrically connected. 
         [0068]    Further, the frame  5  has a support member  51  C for supporting the lead wire  4  formed between the passage  7  of the magnetic circuit  2 C and the terminal parts  6 C as shown in  FIG. 6 . The support member  5 C is formed as a protrusion at a predetermined position of the frame  5  to contact and support the lead wire  4 . The support member  51 C according to the present embodiment is positioned inside of the extra length portion  41  of the lead wire  4 . 
         [0069]    The lead wire  4  is pulled out from near the corner of the voice coil  33 C, passes through the cutout  71  of the passage  7 , and bent substantially along a short axis to be fixed to the terminal part  6 . The bent portions  42  according to this embodiment have a plurality of bent portions  42 A and  42 B in  FIG. 6 . The lead wires  4  having a plurality of bent portions  42 A and  42 B can has the large bearing power and support the voice coil  33 C so as to suppress the generation of abnormal vibration such as the rolling phenomena. Further the balance of the voice coil  33 C can be maintained. 
         [0070]    In an initial state where the level of the sound signal is zero, the lead wire  4  of the voice coil  33 C is pulled out of near the lower end of the voice coil  33 C, passes through the passage  7 , extends obliquely upward from the pull-out position, then bends to be fixed and electrically connected to the inner terminal part  61  configured substantially in the same horizontal level as the pull-out position, as shown in  FIG. 8  for example. In other words, the lead wire  4  passes through the cutout  71  of the passage  7 , and go around a part of the yoke  21  to be connected to the terminal part  6 . 
         [0071]    The speaker device  1 C as configured above, having the lead wire  4  formed as described above, the lead wire  4  is prevented from contacting other member such as the edge  32  and the yoke  21  even when the voice coil  33 C vibrates. 
         [0072]    Although the speaker device  1 C is a thin device having the narrow space between the edge  32  and the yoke  21 , as shown in  FIG. 8 , the deterioration of the acoustic quality due to the contact of the lead wire  4  with other member such as the edge or the yoke can be decreased, because the lead wire  4  of the voice coil  33 C passes through the passage  7  of the magnetic circuit  2  and connects to the inner terminal part  61 . Further, in this embodiment the extra length portion  41  being arranged closer to the frame  5  than to the top portion  34  of the edge  32 , the contact between the extra length portion  41  and the edge  32  can be prevented. The extra length portion can be arranged closer to yoke  21 . 
       [Examples of Passages] 
       [0073]      FIG. 10(A)  is a side view of a passage of the speaker device according to the first embodiment of the present invention.  FIG. 10(B)  is a side view of a passage of the speaker device according to the second embodiment of the present invention. The passage  7  formed in the magnetic circuit  2 C can have a cutout  71  from the upper end portion  21 D to the bottom portion  21 A of the yoke  21  as shown in  FIG. 10A . The passage  7  of the magnetic circuit  2 C can have a cutout  71  in a predetermined distance from the upper end portion  21 D toward the bottom portion  21 A of the yoke  21 , as shown in  FIG. 10B . The magnetic circuit  2 C is configured such that the lead wire  4  does not contact the cutout  71  of the passage  7  even when the voice coil  33  vibrates. 
       [Balance of Voice Coil] 
       [0074]      FIG. 11(A)  is a front view of the speaker device according to another embodiment of the present invention, illustrating a voice coil  33 D,  FIG. 11(B)  is an enlarged view around a winding start position of the conductive wire  401  of the voice coil shown in  FIG. 11(A) ,  FIG. 11(C)  is an enlarged view around an winding end position of the conductive wire  401  of the voice coil shown in  FIG. 11(A) ,  FIG. 11(D)  is a view of a voice coil modified from the voice coil shown in  FIG. 11(B) , and  FIG. 11(E)  is a view of a voice coil modified from the voice coil shown in  FIG. 11(C) . 
         [0075]    In the voice coil  33 D according to the present embodiment, a shape of a pair of the lead wires  4  has a shape to be substantially symmetrical with respect to the center O of the voice coil  33 D, as shown in  FIGS. 11(A) to 11(C) . As the position of a gravity center CG of the voice coil  33 D is different from the center O, the shape of the lead wire  4  is configured to maintain the balance of the voice coil  33 D. A pair of the lead wires  4  is arranged in the substantially symmetrical position with respect to each other so as to maintain the weight balance of the voice coil or the vibrating body to a maximum extent. 
         [0076]    Specifically, as shown in  FIG. 11(A)  to (E) the conductive wire  401  of the voice coil  33 D starts to wind at winding start position  401 S near the corner of the rectangular shape and ends to wind at winding end position  401 E near the opposite corner after a predetermined number of turns (N turns). In this situation, the gravity center CG is weighted from the center O of the voice coil  33 D due to the weight of half a round of the conductive wire  401  from the winding start position  401 S to the winding end position  401 E. 
         [0077]    Therefore, the shape of the leading wire  4  is configured to maintain the balance of the voice coil  33 D as the gravity center CG is weighted from the center O of the voice coil  33 D. Specifically, the gravity center CG of the voice coil  33 D and the position of the bent portion  42  of the lead wire  4  are configured to be on opposite sides to each other with respect to a diagonal line DL passing through the center O of the voice coil  33 D as shown in  FIGS. 11(A) to 11(E) . In the voice coil  33 D as described above, the shape of the bent portion  42  of the pair of the lead wires  4  is configured to maintain the balance of the voice coil  33 D considering a line density of the lead wire  4 . 
         [0078]    The speaker device according to the embodiment of the present invention can maintain the balance of the voice coil  33 D and be prevented from being deterioration of the acoustic quality by applying the above constitution. 
       Fifth Embodiment 
       [0079]      FIG. 12  is a plane view of the speaker device  1 F according to a fifth embodiment of the present invention. The same configurations as the fourth and fifth embodiments are not repeatedly described. The speaker device  1 F according to the present embodiment has a support member  51 E according to fourth embodiment applied closer to the terminal part  6 F than that applied near the center of the short axis of the yoke, as shown in  FIG. 12 . Further the lead wire  4 F according to the present embodiment is formed in a bending shape according to the position of the support member  51 E. 
         [0080]    The speaker device  1 F as structured above, as configured above, has high damping performance since a leading wire  4 F between the passage  7  and the support member  51 E is longer than that according to the fourth embodiment. Further, the support member  51 E being arranged near the terminal part  6 F, the generation of vibration of the lead wire  4 , the stress applied to the connecting portion between the lead wire  4  and the terminal part  6 F, and disconnection of the lead wire  4  from the terminal part  6 F can be prevented. 
       Sixth Embodiment 
       [0081]      FIG. 13  is a plane view of the speaker device  1 G according to a sixth embodiment of the present invention. The same configurations as those of the fourth and fifth embodiments are not repeatedly described. The speaker device  1 G has the passage  7  of a magnetic circuit  2 G formed near the center of the short axis of a yoke  21 G as shown in  FIG. 13 . Further, a terminal part  6 G is configured near the corner of the rectangular magnetic circuit  2 G. A support member  51 G is configured near the terminal part  6 G. The lead wire  4  pulled out of the voice coil  33 G passes through the cutout  71 G of the passage  7 G, bends toward the terminal part  6 G, contacts the support member  51 G, and gets fixed and electrically connected to the terminal part  6 G 
         [0082]    The speaker device  1 G as structured above can reduce the space for the extra length portion of the lead wire comparing with the fourth and fifth embodiments. Further, the lead wire  4  supporting the voice coil  33 G along its longitudinal axis, it has a high damping performance comparing with the fourth and fifth embodiments. 
         [0083]    The present invention is not limited to the above-mentioned embodiments. The present invention can be performed not only by each embodiment but by a combination of these embodiments. An outer-magnet-type magnetic circuit, for example can be used as the magnetic circuit of the speaker device according to the present invention. The outer-magnet-type magnetic circuit has a yoke with a center pole in the central portion, a ring-shaped magnet engaged with the center pole and a ring-shaped plate disposed on the ring-shaped magnet. And, a cutout of a passage is provided at either the magnet or the plate. The speaker device applying the outer-magnet-type magnetic circuit as structured above has the lead wire pulled out of the voice coil freely fitted in the magnetic circuit and connected to the terminal part formed at the frame through the cutout, or the passage, thus the contact of the lead wire with other member can be prevented. 
         [0084]    Also, in the above embodiment, the cutout (opening) is applied to the passage  7  of the magnetic circuit  2 , but the passage is not limited to the embodiment described above. For example, the passage of the magnetic circuit can be formed, as a through-hole provided on the side of the yoke of an inner-magnet-type magnetic circuit. The lead wire pulled out of the voice coil freely fitted in a magnetic gap G formed in inner-magnet-type magnetic circuit is connected to a terminal part provided in proximity of a frame through the through-hole provided at the yoke. The speaker device as described above can apply substantially uniform magnetic field intensity to the magnetic gap. 
         [0085]    The voice coil according to the fourth embodiment is formed substantially in a rectangular shape. However the invention is not limited to the configuration. The voice coil can be configured to have a track shape including at least a straight portion, a substantially rectangular shape, an elliptical shape or a round shape, etc corresponding to the configuration of a speaker. The lead wire contacts the support member  51  according to the embodiments described above. However the invention is not limited to this configuration. The lead wire can be configured not to contact the support member  51 . Further, the support member  51  is provided in proximity of the frame  5 . However the support member  5  can be eliminated as necessary. 
         [0086]    The speaker device  1  according to the present invention, includes a magnetic circuit  2  having a magnetic gap where a voice coil  33  freely fits, a vibrating body  3  bonded directly or indirectly to the voice coil  33 , a frame  5  for supporting the vibrating body  3  and housing the magnetic circuit  2 , and a terminal part  6  to which the lead wire  4  of the voice coil  33  is connected. A passage  7  is arranged between the voice coil  33  which is freely fitted in the magnetic gap G and the terminal part  6  provided in proximity of the frame  5 . The lead wire  4  is pulled out of the voice coil  33 . Thus, even when the speaker device  1  is thin and small, the generation of abnormal noise due to contact of the lead wire  4  with other member can be prevented. In addition, breakage of the lead wire of the voice coil can be prevented.