Patent Publication Number: US-2011075880-A1

Title: Speaker damper and speaker including the same

Description:
TECHNICAL FIELD  
     The present invention relates to a speaker damper which is to be used in a small and thin dynamic speaker that can be employed in a portable telephone or the like, and also to a speaker including a speaker damper. 
     BACKGROUND ART  
     A damper of a dynamic speaker cooperates with a diaphragm edge portion to play a role of holding a vibration system to a correct position to realize accurate vibration of the vibration system. Conductors for electrically connecting the voice coil to external connection terminals are disposed integrally with a damper (Patent Literature 1) 
     PRIOR ART LITERATURE  
     Patent Literature   
     [Patent Literature 1] Japanese Patent Application Laid-Open No. 9-307993 
     SUMMARY OF THE INVENTION  
     Problem to be Solved by the Invention  
     A damper having conductors can eliminate a process of laying lead wires of a voice coil by means of forming. The process constitutes a bottleneck of improvement of the productivity of a speaker. However, the voice coil and the damper conductors must be electrically connected to each other by using other lead wires, thereby causing the number of assembling steps and the component cost to be increased. Therefore, the configuration has an adverse effect on improvement of the productivity of a speaker. 
     It is an object of the invention to provide a speaker damper which can realize improvement of the productivity of a speaker, and a speaker including the speaker damper. 
     Means for Solving the Problem   
     The speaker damper of the invention is used in a speaker including: a magnetic circuit having a yoke, a magnet, and a pole piece; a vibration system having a voice coil and diaphragm which are connected to each other through a voice coil bobbin; and a frame which holds the magnetic circuit, the vibration system, and external connection terminals, the voice coil being placed in a magnetic gap, and characterized in that voice coil lead wires are guided to the external connection terminals while being laid on one surface. The process of laying the voice coil lead wires by means of forming is realized not in the air of the interior of the frame, but on the one surface of the damper. Therefore, the process of laying the voice coil lead wires by means of forming can be performed easily and properly, the forming of the voice coil lead wires can be stabilized, and the positional accuracy of the voice coil lead wires with respect to the external connection terminals can be improved, so that improvement of the productivity of a speaker can be realized. The flex resistance of the voice coil lead wires can be improved, and also improvement of the input resistance characteristics of a speaker can be realized. 
     In the speaker damper of the invention, a damper body, and lead portions in which voice coil lead wires are guided to the external connection terminals while being laid on one surface are disposed, and the damper body includes: a movable portion which is coupled to an end portion of the voice coil bobbin opposite to the diaphragm; a fixed portion which is coupled to a stationary portion of the speaker; and a flexible portion through which the movable portion and the fixed portion are connected to each other, or the flexible portion includes a specific flexible portion which functions also as the lead portion. According to the configuration, the lower end of the vibration system which has a maximum distance from a diaphragm edge portion is supported by the damper body, and hence a high damper performance can be obtained. Moreover, two points, i.e., the upper and lower ends of the vibration system are supported by the diaphragm edge portion and the damper body, and hence the vibration system can produce more stable and accurate vibration. Therefore, the input resistance characteristics of a speaker can be further improved. 
     A speaker damper which has the above-described configuration may be formed by performing a punching process on one sheet-like member to have a planar structure. According to the configuration, a damper which can realize improvement of the productivity, thinning, and improvement of the input resistance characteristics of a speaker can be economically obtained. 
     The speaker of the invention is characterized in that it includes the the speaker damper of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         FIGS. 1A to 1C  are views illustrating a speaker damper of an embodiment (Embodiment 1) of the invention,  FIG. 1A  is a plan view of the speaker damper,  FIG. 1B  is a sectional view taken along line A-A′ in  FIG. 1A , and  FIG. 1C  is a sectional view taken along line B-B′ in  FIG. 1A . 
         FIG. 2  is a plan view of a speaker including the speaker damper shown in  FIGS. 1A to 1C . 
         FIG. 3  is a sectional view taken along line A-A′ in  FIG. 2 . 
         FIG. 4  is a sectional view taken along line B-B′ in  FIG. 2 . 
         FIG. 5  is an exploded perspective view of the speaker of  FIG. 2 . 
         FIGS. 6A to 6C  are views illustrating another speaker damper of another embodiment (Embodiment 2) of the invention,  FIG. 6A  is a plan view of the other speaker damper,  FIG. 6B  is a sectional view taken along line A-A′ in  FIG. 6A , and  FIG. 6C  is a sectional view taken along line B-B′ in  FIG. 6A . 
         FIG. 7  is a plan view of another speaker including the other speaker damper shown in  FIGS. 6A to 6C . 
         FIG. 8  is a sectional view taken along line A-A′ in  FIG. 7 . 
         FIG. 9  is a sectional view taken along line B-B′ in  FIG. 7 . 
     
    
    
     MODE FOR CARRYING OUT THE INVENTION   
     Embodiment 1  
     Hereinafter, an embodiment (Embodiment 1) of the invention will be described with reference to  FIGS. 1A to 5 .  FIGS. 1A to 1C  are views illustrating a speaker damper of the embodiment (Embodiment 1) of the invention,  FIG. 1A  is a plan view of the speaker damper,  FIG. 1B  is a sectional view taken along line A-A′ in  FIG. 1A ,  FIG. 1C  is a sectional view taken along line B-B′ in  FIG. 1A ,  FIG. 2  is a plan view of a speaker including the speaker damper shown in  FIGS. 1A to 1C ,  FIG. 3  is a sectional view taken along line A-A′ in  FIG. 2 ,  FIG. 4  is a sectional view taken along line B-B′ in  FIG. 2 , and  FIG. 5  is an exploded perspective view of the speaker of  FIG. 2 . 
     As shown in  FIGS. 2 to 5 , the speaker  1  is mainly configured by: a yoke  11 , magnet  12 , and pole piece  13  which constitute a magnetic circuit  10 ; a voice coil  21  and diaphragm  22  which constitute a vibration system  20 ; an external connection plate  31  on which a pair of external connection terminals  30  to be electrically connected to an external circuit are disposed; a baffle  40  which covers and protects the diaphragm  22 ; a damper (speaker damper)  50  of the invention; and a frame  60  to which the magnetic circuit  10 , the vibration system  20 , the external connection plate  31 , and the damper  50  are attached to assemble the speaker  1 , and which cooperates with the baffle  40  to constitute a case of the speaker  1 . 
     The frame  60  is formed into a shallow bottomed rectangular tubular shape by perpendicularly raising an outer sidewall  62  from the outer peripheral edge of a rectangle bottom plate  61 . The yoke  11  is integrally formed in a middle portion of the frame. Namely, an oval yoke outer sidewall  11   a  is perpendicularly raised from the inner surface of a middle portion of the bottom plate  61 , and the middle portion of the bottom plate  61  which is inside the yoke outer sidewall  11   a  is used as a yoke bottom plate, thereby forming the bottomed oval cylindrical yoke  11  which is shallower than the frame  60 , and which is concentric with the frame  60 . 
     In the bottom plate  61 , a step  63  is formed in order to raise by one step a bottom plate  61   a  which is in the bottom plate  61  surrounding the yoke  11 , and which is in the periphery of one semi-arcuate end portion of the yoke  11 . In one end portion (in  FIG. 2 , an upper end portion) in the longitudinal direction (in  FIG. 2 , the vertical direction) of the frame  60 , a raised bottom portion  64  which functions as a lead portion support portion of the damper  50  is disposed, and a recess portion  65  functioning as a portion to which the external connection plate is to be attached is disposed on the outer bottom face of an end portion in the longitudinal direction of the frame  60  that is the rear side of the raised bottom portion  64 . Through holes  66  functioning as connecting portions between the pair of external connection terminals  30  placed outside the frame  60 , and two voice coil lead wires  21   b  placed inside the frame  60  are disposed in both end portions of the bottom plate  61   a  of the raised bottom portion  64 , respectively. 
     Four voice coil positioning pins (not shown) are used for, during assembly of the speaker  1 , holding and positioning the voice coil  21  in a total of four places, i.e., two places on the longitudinal direction center line, and two places on the short-side direction center line (in  FIG. 2 , the lateral direction). In the bottom plate  61 , through holes  67 ,  67 ′ for inserting the four voice coil positioning pins from the bottom side of the frame  60  into the interior thereof are disposed in a total of four places corresponding to the insertion positions of the four voice coil positioning pins, i.e., two places on the longitudinal direction center line of the frame  60 , and two places on the short-side direction center line. 
     During use of the speaker  1 , the through holes  67 ,  67 ′ function as rear sound holes through which air (sound) that is in the frame  60 , and that is pressed by the diaphragm  22  escapes to the outside. The two through holes  67  on the longitudinal direction center line of the frame  60  are disposed in the bottom plate  61  which functions as the yoke bottom plate inside the yoke outer sidewall  11   a,  and mainly used for allowing air pressed by a diaphragm middle portion  23  of the diaphragm  22  to escape, and the two through holes  67 ′ on the short-side direction center line of the frame  60  are disposed in the both portions of the bottom plate  61  outside and inside the yoke outer sidewall  11   a,  and used for allowing air pressed not only by the diaphragm middle portion  23  of the diaphragm  22  but also by a diaphragm edge portion  24  to escape. 
     Discontinued portions  11   b  functioning as voice coil lead-wire drawn out ports are disposed in two places on the short-side direction center line of the yoke outer sidewall  11   a,  respectively. In the two discontinued portions  11   b,  the two through holes  67 ′ on the short-side direction center line of the frame  60  are disposed in the both portions of the bottom plate  61  outside and inside the yoke outer sidewall  11   a.    
     A horizontal step face  68  which functions as a support face for the vibration system  20  is disposed in the upper inner face of the outer sidewall  62 . 
     The yoke-integral type frame  60  is formed by performing a press process on one flat metal plate (magnetic material), and has an axisymmetric structure in which the short-side direction center line is set as the symmetric axis. 
     The magnet  12  is configured by a long columnar permanent magnet. The pole piece  13  is configured by an oval flat metal plate (magnetic material). The magnet  12  is bonded and fixed to the inner bottom face of the yoke  11 , and the pole piece  13  is bonded and fixed to the upper face of the magnet  12 , thereby configuring the oval magnetic circuit  10  of the internal magnet type. The magnetic circuit  10  forms an oval magnetic gap  14  between an upper portion of the yoke outer sidewall  11   a  and the pole piece  13 . 
     The voice coil  21  is formed into an oval cylindrical shape by winding a copper wire or the like around the outer peripheral face of an oval cylindrical voice coil bobbin  21   a  made of a plastic film or the like. The voice coil lead wires  21   b  for electrically connecting the voice coil  21  to the external connection terminals  30  are connected to both end portions of the winding, respectively. The voice coil lead wires  21   b  are drawn out from two places of a lower end portion of the voice coil  21  and on the short-side direction center line of the voice coil  21 . 
     The diaphragm  22  is configured by a thin film such as a plastic film of polyethylene terephthalate (PET), polyetherimide (PEI), polyimide (PI), or the like. The diaphragm  22  has an oval diaphragm middle portion  23  which covers the upper end opening of the voice coil  21 , and the diaphragm edge portion  24  which surrounds the whole circumference of the diaphragm middle portion  23 , and in which the outer shape is formed into a rectangular shape so as to coincide with that of the frame  60 . The diaphragm  22  is formed by separately forming the diaphragm middle portion  23  and the diaphragm edge portion  24 , and then bonding and fixing together an outer peripheral edge portion of the diaphragm middle portion  23  and an inner peripheral edge portion of the diaphragm edge portion  24 . Alternatively, the diaphragm  22  may be formed by integrally forming the diaphragm middle portion  23  and the diaphragm edge portion  24 . A honeycomb-like reinforcement rib  25  is formed on the whole face of the diaphragm middle portion  23 , so that the whole face of the diaphragm middle portion  23  is uniformly reinforced, and the diaphragm middle portion  23  is provided with necessary strength (rigidity) while the diaphragm middle portion  23  is thinned (finally flattened from a dome-like shape to a flat plate-like shape), thereby realizing thinning of the speaker  1 . The illustrated reinforcement rib  25  is formed into a groove-like shape in which the upper face of the diaphragm middle portion  23  is concave and the lower face is convex. Alternatively, the reinforcement rib may be formed into a bulge-like shape in which the upper face of the diaphragm middle portion  23  is convex and the lower face is concave. A rectangular diaphragm ring  26  which is made of a metal such as brass, and which functions as a washer is bonded and fixed to the rear side of an outer peripheral edge portion of the diaphragm edge portion  24 . 
     The vibration system  20  is configured by bonding and fixing the rear side of the interface between the diaphragm middle portion  23  of the diaphragm  22  and the diaphragm edge portion  24  to an upper end portion of the voice coil bobbin  21   a,  and hangingly fixing the voice coil  21  to the rear side of the interface between the diaphragm middle portion  23  of the diaphragm  22  and the diaphragm edge portion  24  through the voice coil bobbin  21   a.    
     The vibration system  20  is held by coupling its upper end portion to the frame  60  which is the stationary portion of the speaker  1  by means of the diaphragm edge portion  24 . Namely, the outer peripheral edge portion of the diaphragm edge portion  24  is bonded and fixed through the diaphragm ring  26  to the step face  68  which is disposed on the inner face of the upper portion of the outer sidewall  62  as the support face for the vibration system  20 , whereby the diaphragm  22  is disposed there so as to cover the upper opening of the frame  60 . The voice coil  21  is inserted and placed in the magnetic gap  14  from the upper side. The diaphragm edge portion  24  plays a role of holding the vibration system  20  to the correct position to realize accurate vibration of the vibration system  20 . 
     The external connection plate  31  is a printed circuit board in which two external connection terminals  30  are integrally disposed in an insulated state. The plate is attached to the recess portion  65  of the frame  60 , and one-end sides of the external connection terminals  30  are exposed through the through holes  66  to the both end portions of the inner bottom face of the raised bottom portion  64 , respectively. The other end sides of the external connection terminals  30  are exposed to the rear side of the external connection plate  31  in a substantially flush manner, and electrically connected to an external circuit (printed circuit board) of an electronic apparatus such as a portable telephone onto which the speaker  1  is mounted. 
     The baffle  40  is formed by applying a pressing process on a metal flat plate, into a ceiled rectangular tubular shape which is shallower than the frame  60 , and fitted to the upper opening of the frame  60  to cover and protect the the diaphragm  22 . The lower end of the outer side wall of the baffle  40  presses and fixes from the upper side the outer peripheral edge portion of the diaphragm edge portion  24  and the diaphragm ring  26  against the step face  68 . A front sound hole  41  having a substantially same shape as the diaphragm middle portion  23  is disposed in the top plate of the baffle  40 . To the outer top face of the baffle  40  and the outer bottom face of the frame  60 , damping cloth (not shown) having air permeability is bonded in order to cover the front sound hole  41  and rear sound holes (through holes  67 ,  67 ′) which are formed in the faces, adjust the acoustic performance of the speaker  1 , and prevent dust from entering the interior of the speaker  1 . 
     The speaker  1  includes: the magnetic circuit  10  having the yoke  11 , the magnet  12 , and the pole piece  13 ; the vibration system  20  having the voice coil  21  and diaphragm  22  which are connected to each other through the voice coil bobbin  21   a;  and the frame  60  which holds the magnetic circuit  10  and the vibration system  20 , and the voice coil  21  is placed in the magnetic gap  14 , thereby configuring the dynamic speaker  1 . 
     In the dynamic speaker  1 , when, in a state where the voice coil lead wires  21   b  are connected to the external connection terminals  30  inside the frame  60 , a current is supplied from the external circuit to the voice coil  21  through the external connection terminals  30  and the voice coil lead wires  21   b,  the voice coil  21  is caused to perform vertical piston motion or vibrate by an interaction between the magnetic fluxes which are directed in a substantially horizontal direction in the magnetic gap  14 , and the current flowing through the voice coil  21 . The vibration is transmitted to the diaphragm  22  by the voice coil bobbin  21   a,  and the diaphragm middle portion  23  vibrates while setting the diaphragm edge portion  24  as a fulcrum, thereby generating a sound. Namely, the speaker converts electricity into a sound. 
     The damper  50  is disposed in the speaker  1  in order to cooperate with the diaphragm edge portion  24  to play a role of holding the vibration system  20  to a correct position to realize accurate vibration of the vibration system  20 . The damper is configured so that the voice coil lead wires  21   b  are laid on one surface to be guided to the external connection terminals  30 . 
     As shown in  FIGS. 1A ,  1 B, and  1 C, the damper body  51  which exerts a damper function, and a pair of lead portions  52  for guiding the two voice coil lead wires  21   b  to the external connection terminals  30  to which the wires are to be connected are disposed in the damper  50 . The damper body  51  and the lead portions  52  are placed in one plane. The damper  50  is formed by performing a punching process on one sheet-like member (non-magnetic material) such as a plastic film of polyethylene terephthalate (PET), polyetherimide (PEI), polyimide (PI), or the like, and has a planar structure. 
     In the damper body  51 , an outer ring portion  51   a  that is a movable portion which is coupled to a lower end portion of the voice coil bobbin  21   a  opposite to the diaphragm  22 , an inner ring portion  51   b  that is a fixed portion coupled to the magnet  12  of the magnetic circuit  10  which is a stationary portion of the speaker  1 , and flexible portions  51   c  through which the outer ring portion  51   a  and the inner ring portion  51   b  are connected to each other are disposed. The damper body is configured so as to support the vibration system  20  with respect to the magnet  12  of the magnetic circuit  10 . 
     The outer ring portion  51   a  is formed into an oval annular member which has a constant width over the whole circumference, so as to cause the outer peripheral end face of the outer ring portion  51   a  to contact with the inner peripheral face of the voice coil bobbin  21   a,  or the one surface of the outer ring portion  51   a  to contact with the lower end face of the voice coil bobbin  21   a.    
     The inner ring portion  51   b  is formed into an oval annular member which has a constant width that is substantially equal to that of the outer ring portion  51   a,  over the whole circumference, which is smaller than the outer ring portion  51   a,  and which is concentric with the outer ring portion  51   a,  so as to cause the inner peripheral end face of the inner ring portion  51   b  to contact with the outer peripheral face of the magnet  12 , or the one surface of the inner ring portion  51   b  to contact with a horizontal step face  70  which is disposed as an upward or downward inner ring portion bonding portion on the outer peripheral face of the magnet  12 . The gap between the outer ring portion  51   a  and the inner ring portion  51   b  is constant over the whole circumference. 
     When the step face  70  is disposed directly on the outer peripheral face of the magnet  12 , the production cost of the magnet  12  is high. Therefore, an oval cylindrical damper ring  71  made of plastic (non-magnetic material) or the like is disposed, the step face  70  is disposed on the outer peripheral face of the damper ring  71 , and the damper ring  71  is fitted onto the magnet  12 , whereby the step face  70  is disposed on the outer peripheral face of the magnet  12 . 
     The flexible portions  51   c  are configured by a plurality (in the illustrated example, eight) of flexurally deformable plate spring-like members which are bent in a crank-like manner in one plane, and which have a constant width that is substantially equal to the widths of the outer ring portion  51   a  and the inner ring portion  51   b  over the whole circumference. Intermediate portions of the flexible portions  51   c  are placed along an oval center line which is drawn between the outer ring portion  51   a  and the inner ring portion  51   b,  and which is concentric therewith. Outward ends of the flexible portions  51   c  are coupled to the inner peripheral edge of the outer ring portion  51   a,  and the inward other ends of the flexible portions  51   c  are coupled to the outer peripheral edge of the inner ring portion  51   b.  The flexible portions  51   c  cause the outer ring portion  51   a  and the inner ring portion  51   b  to be connected to each other at a plurality (in the illustrated example, eight) of places which are shifted in the circumferential direction of the damper body  51 . The connection pattern between the outer ring portion  51   a  and the inner ring portion  51   b  through the flexible portions  51   c  is formed into a shape which does not cause the damper performance to be unbalanced depending on the circumferential position of the damper body  51 . Namely, the pattern has a symmetrical shape such as an axisymmetrical shape in which the center line in the longitudinal direction center line (in  FIG. 1A , the vertical direction) or short-side direction center line (in  FIG. 1A , the lateral direction) of the damper body  51  is set as the symmetrical axis, or a point (rotational) symmetrical shape in which the center of the damper body  51  is set as the symmetry center. In the illustrated example, the pattern has an axisymmetrical shape in which any of the center lines in the longitudinal direction and short-side direction of the damper body  51  can be set as the symmetrical axis, and a 180-degree point symmetrical shape in which the center of the damper body  51  is set as the symmetry center. 
     Each of the paired lead portions  52  is configured by a flexurally deformable thin plate spring-like member which is bent into an L-like shape in one plane. The lead portions are elongated respectively from two places on the short-side direction center line of the outer peripheral edge of the outer ring portion  51   a  to both end portions of the raised bottom portion  64  which are disposed as lead portion supporting portions for the damper  50  in one end portion in the longitudinal direction of the frame  60 , while passing through the discontinued portions  11   b  which are disposed in two places on the short-side direction center line of the yoke outer sidewall  11   a,  and between the yoke outer sidewall  11   a  and the outer sidewall  62  of the frame  60 . 
     In tip end portions of the lead portions  52 , formed are ring portions  52   a  which surround the through holes  66  that are disposed in both end portions of the bottom plate  61   a  of the raised bottom portion  64  as connecting portions between the pair of external connection terminals  30  placed outside the frame  60 , and the two voice coil lead wires  21   b  placed inside the frame  60 , which are to be bonded and fixed to the inner surface of the raised bottom portion  64  surrounding the through holes  66 . 
     Bonding layers  52   c  (the hatched portions in  FIG. 1A ) are disposed on one surfaces (upper faces) of the lead portions  52  in order to bond and fix the voice coil lead wires  21   b.  Each of the bonding layers  52   c  has a linear shape which is continuous from a basal end portion of the corresponding lead portion  52  coupled to the outer ring portion  51   a,  to an inner hole  52   b  of the corresponding ring portion  52   a  that is formed in a tip end portion of the lead portion  52 , or a broken line like shape in which one or more interrupted parts are formed. The bonding layers  52   c  are formed by, for example, application of an adhesive material. 
     The lead portions  52  are elongated from the damper body  51  in an axisymmetrical shape in which the center line in the longitudinal direction of the damper body  51  is set as the symmetrical axis. The damper  50  has as a whole an axisymmetric structure in which the longitudinal-direction center line of the damper body  51  is set as the symmetrical axis. 
     As shown in  FIGS. 2 to 4 , the vibration system  20  in which the upper end portion is connected and held to the frame  60  that is the stationary portion of the speaker  1  by the diaphragm edge portion  24  is further connected and held in the lower end portion by the damper  50  to the magnet  12  of the magnetic circuit  10  that is the stationary portion of the speaker  1 . Namely, the damper body  51  is horizontally stretched between the lower end portion of the voice coil bobbin  21   a  and the magnet  12  by: bonding and fixing the outer peripheral end face of the outer ring portion  51   a  to the inner peripheral face of the voice coil bobbin  21   a;  bonding and fixing the one surface (upper face) of the outer ring portion  51   a  to the lower end face of the voice coil bobbin  21   a,  and the inner peripheral end face of the inner ring portion  51   b  to the outer peripheral face of the magnet  12 ; or bonding and fixing the one surface (upper face) of the inner ring portion  51   b  to the upward or downward step face  70  which is disposed on the outer peripheral face of the magnet  12  through the damper ring  71 , whereby the damper body  51  is enabled to exert a damper function. 
     At this time, the lead portions  52  are elongated respectively to the end portions of the raised bottom portion  64  from the two places on the short-side direction center line of the outer peripheral edge of the outer ring portion  51   a,  while passing through the discontinued portions  11   b  which are disposed in two places on the short-side direction center line of the yoke outer sidewall  11   a,  and between the yoke outer sidewall  11   a  and the outer sidewall  62  of the frame  60 . Therefore, the lead portions  52  are horizontally stretched between the two places on the short-side direction center line of the outer peripheral edge of the outer ring portion  51   a,  and the end portions of the raised bottom portion  64 , in the same plane as the damper body  51 , by bonding and fixing the ring portions  52   a  which are formed in the tip end portions of the lead portions  52 , to the inner surface of the raised bottom portion  64  surrounding the through holes  66  disposed in the both end portions of the bottom plate  61   a  of the raised bottom portion  64 , so that the two voice coil lead wires  21   b  are guided by the lead portions  52  to the external connection terminals  30  to which the wires are to be connected. 
     Namely, the configuration where the two voice coil lead wires  21   b  which are drawn out from the two places of the lower end portion of the voice coil  21  that are directly above the basal end portions of the lead portions  52 , and on the short-side direction center line of the voice coil  21  are bonded and fixed to the bonding layers  52   c  disposed on the one surfaces (upper faces) of the lead portions  52  allows the two voice coil lead wires  21   b  to be bent into an L-like shape along the lead portions  52 , and to be guided from the two places on the short-side direction center line of the outer peripheral edge of the outer ring portion  51   a,  to the end portions of the raised bottom portion  64 , while passing through the discontinued portions  11   b  which are disposed in two places on the short-side direction center line of the yoke outer sidewall  11   a,  and between the yoke outer sidewall  11   a  and the outer sidewall  62  of the frame  60 . In this way, the process of laying the voice coil lead wires  21   b  by means of forming to the external connection terminals  30  to which the wires are to be connected is realized not in the air of the interior of the speaker  1 , but on the one surfaces of the lead portions  52  disposed in the damper body  51 . 
     When the voice coil lead wires  21   b  are bonded and fixed to the bonding layers  52   c  of the lead portions  52 , enough slacks are provided between the end portions of the voice coil lead wires  21   b  on the drawn out side from the voice coil  21 , and the portions where the lead portions  52  are bonded and fixed to the bonding layers  52   c,  in order to allow and not to impeded the voice coil  21  to vibrate. 
     After the laying process by means of forming, the two voice coil lead wires  21   b  are connected by soldering or spot welding  80  to one end sides of the external connection terminals  30  which are exposed in the both end portions of the inner bottom face of the raised bottom portion  64  through the inner holes  52   b  of the ring portions  52   a  that are formed in the tip end portions of the lead portions  52 , and the through holes  66  that are disposed in the both end portions of the bottom plate  61   a  of the raised bottom portion  64 . 
     The lead portions  52  exert not only a function of, in the assembling of the speaker  1 , guiding the two voice coil lead wires  21   b  to the external connection terminals  30  to which the wires are to be connected, but also the following functions. During the use of the speaker  1 , the tip end portions (ring portions  52   a ) of the lead portions  52  function as a fixed portion coupled to the frame  60  which is a stationary portion of the speaker  1 , and the areas of the lead portions  52  from the basal end portions to the tip end portions function as a flexible portion through which the outer ring portion  51   a  functioning as a movable portion coupled to the end portion of the voice coil bobbin  21   a  opposite to the diaphragm  22 , and the tip end portions (ring portions  52   a ) of the lead portions  52  functioning as the fixed portion coupled to the frame  60  which is a stationary portion of the speaker  1  are coupled to each other, with the result that a damper function is exerted. 
     As described above, the damper  50  is used in the speaker including: the magnetic circuit  10  having the yoke  11 , the magnet  12 , and the pole piece  13 ; the vibration system  20  having the voice coil  21  and diaphragm  22  which are connected to each other through the voice coil bobbin  21   a;  and the frame  60  which holds the magnetic circuit  10 , the vibration system  20 , and the external connection terminals  30 , the voice coil  21  being placed in the magnetic gap  14 , and the voice coil lead wires  21   b  are guided to the external connection terminals  30  while being laid on the one surface. In the embodiment, the lead portions  52  which are elongated from the damper body  51  to the external connection terminals  30 , and in which the voice coil lead wires  21   b  are bonded and fixed to the one surface to be guided to the external connection terminals  30  are disposed, and the process of laying the voice coil lead wires  21   b  by means of forming is realized not in the air of the interior of the frame  60 , but on the one surfaces of the lead portions  52  disposed in the damper body  51 , or by bonding and fixing the voice coil lead wires  21   b  to the one surfaces of the lead portions  52 . Therefore, the process of laying the voice coil lead wires  21   b  by means of forming can be performed easily and properly, the forming of the voice coil lead wires  21   b  can be stabilized, and the positional accuracy of the voice coil lead wires  21   b  with respect to the external connection terminals  30  can be improved, so that improvement of the productivity of the speaker  1  can be realized. The flex resistance of the voice coil lead wires  21   b  can be improved, and also improvement of the input resistance characteristics of the speaker  1  can be realized. 
     In the damper body  51 , the movable portion  51   a  which is coupled to the end portion of the voice coil bobbin  21   a  opposite to the diaphragm  22 , the fixed portion  51   b  which is coupled to the stationary portion (the frame  60  and the magnetic circuit  10 ) of the speaker  1 , and the flexible portions  51   c  through which the movable portion  51   a  and the fixed portion  51   b  are connected to each other are disposed, and the lower end of the vibration system  20  which has the maximum distance from the diaphragm edge portion  24  is supported by the damper body  51 . Therefore, a high damper performance can be obtained. Moreover, two points, i.e., the upper and lower ends of the vibration system  20  are supported by the diaphragm edge portion  24  and the damper body  51 , and hence the vibration system  20  can produce more stable and accurate vibration. Therefore, the input resistance characteristics of the speaker  1  can be further improved. 
     In the damper body  51 , the outer ring portion  51   a  functioning as the movable portion which is coupled to the end portion of the voice coil bobbin  21   a  opposite to the diaphragm  22 , the inner ring portion  51   b  functioning as the fixed portion which is coupled to the magnet  12  of the magnetic circuit  10  functioning as the stationary portion of the speaker, and the flexible portions  51   c  through which the outer ring portion  51   a  and the inner ring portion  51   b  are connected to each other are disposed, and the vibration system  20  is supported with respect to the magnet  12 . The lead portions  52  are elongated from the outer ring portion  51   a.  The damper body  51  can be disposed by effectively using the space between the pole piece  13  and the yoke  11 , and without particularly ensuring a space. Therefore, the speaker  1  can be further thinned, and the input resistance characteristics of the speaker  1  can be further improved. 
     Moreover, the damper body  51  and the lead portions  52  are placed in the one plane, and the process of laying the voice coil lead wires  21   b  by means of forming is realized by bonding and fixing the voice coil lead wires  21   b  to the one flat surfaces of the lead portions  52 . Therefore, the process of laying the voice coil lead wires  21   b  by means of forming can be performed easily and properly, so that improvement of the productivity of the speaker  1 , further thinning of the speaker  1 , and further improvement of the input resistance characteristics of the speaker  1  can be realized. 
     Furthermore, the damper  50  is formed by performing a punching process on one sheet-like member, and has a planar structure. Therefore, the damper  50  which can realize improvement of the productivity, thinning, and improvement of the input resistance characteristics of the speaker  1  can be economically obtained. 
     Furthermore, the speaker  1  includes the damper  50  of the embodiment, and hence it is possible to realize a thin speaker which has a high productivity and a high input resistance. 
     Embodiment 2  
     Next, another embodiment (Embodiment 2) of the invention will be described with reference to  FIGS. 6A to 9 .  FIGS. 6A to 6C  are views illustrating another speaker damper of the other embodiment (Embodiment 2) of the invention,  FIG. 6A  is a plan view of the other speaker damper,  FIG. 6B  is a sectional view taken along line A-A′ in  FIG. 6A ,  FIG. 6C  is a sectional view taken along line B-B′ in  FIG. 6A ,  FIG. 7  is a plan view of another speaker including the other speaker damper shown in  FIGS. 6A to 6C ,  FIG. 8  is a sectional view taken along line A-A′ in  FIG. 7 , and  FIG. 9  is a sectional view taken along line B-B′ in  FIG. 7 . 
     As shown in  FIGS. 7 to 9 , the other speaker  101  is mainly configured by: a yoke  111 , magnet  112 , and pole piece  113  which constitute a magnetic circuit  110 ; a voice coil  121  and diaphragm  122  which constitute a vibration system  120 ; an external connection plate  131  on which a pair of external connection terminals  130  to be electrically connected to an external circuit are disposed; a baffle  140  which covers and protects the diaphragm  122 ; another damper (other speaker damper)  150  of the invention; and a frame  160  to which the magnetic circuit  110 , the vibration system  120 , the external connection plate  131 , and the other damper  150  are attached to assemble the other speaker  101 , and which cooperates with the baffle  140  to constitute a case of the other speaker  1 . 
     The frame  160  is formed into a shallow bottomed rectangular tubular shape by perpendicularly raising an outer sidewall  162  from the outer peripheral edge of a rectangle bottom plate  161 . The yoke  111  is integrally formed in a middle portion of the frame. Namely, an oval yoke outer sidewall  111   a  is perpendicularly raised from the inner surface of a middle portion of the bottom plate  161 , and the middle portion of the bottom plate  161  which is inside the yoke outer sidewall  111   a  is used as a yoke bottom plate, thereby forming the bottomed oval cylindrical yoke  111  which is shallower than the frame  160 , and which is concentric with the frame  160 . 
     In the bottom plate  161 , a step  163  is formed in order to raise by one step a bottom plate  161   a  which is in the bottom plate  161  surrounding the yoke  111 , and which is in the periphery of one semi-arcuate end portion of the yoke  111 . In one end portion (in  FIG. 7 , an upper end portion) in the longitudinal direction (in  FIG. 7 , the vertical direction) of the frame  160 , a raised bottom portion  164  is disposed, and a recess portion  165  functioning as a portion to which the external connection plate is to be attached is disposed on the outer bottom face of an end portion in the longitudinal direction of the frame  160  that is the rear side of the raised bottom portion  164 . Through holes  166  functioning as connecting portions between the pair of external connection terminals  130  placed outside the frame  160 , and two voice coil lead wires  121   b  placed inside the frame  160  are disposed in both end portions of the bottom plate  161   a  of the raised bottom portion  164 , respectively. 
     Four voice coil positioning pins (not shown) are used for, during assembly of the speaker  101 , holding and positioning the voice coil  121  in a total of four places, i.e., two places on the longitudinal direction center line, and two places on the short-side direction center line (in  FIG. 7 , the lateral direction). In the bottom plate  161 , through holes  167 ,  167 ′ for inserting the four voice coil positioning pins from the bottom side of the frame  160  into the interior thereof are disposed in a total of four places corresponding to the insertion positions of the four voice coil positioning pins, i.e., two places on the longitudinal direction center line of the frame  160 , and two places on the short-side direction center line. 
     During use of the speaker  101 , the through holes  167 ,  167 ′ function as rear sound holes through which air (sound) that is in the frame  160 , and that is pressed by the diaphragm  122  escapes to the outside. The two through holes  167  on the longitudinal direction center line of the frame  160  are disposed in the bottom plate  161  which functions as the yoke bottom plate inside the yoke outer sidewall  111   a,  and mainly used for allowing air pressed by a diaphragm middle portion  123  of the diaphragm  122  to escape, and the two through holes  167 ′ on the short-side direction center line of the frame  160  are disposed in the both portions of the bottom plate  161  outside and inside the yoke outer sidewall  111   a,  and used for allowing air pressed not only by the diaphragm middle portion  123  of the diaphragm  122  but also by a diaphragm edge portion  124  to escape. 
     Discontinued portions  111   b,    111   b ′ are disposed in a total of four places, i.e., two places on the longitudinal direction center line of the yoke outer sidewall  111   a,  and two places on the short-side direction center line, respectively. The two discontinued portions  111   b  on the longitudinal direction center line of the yoke outer side-wall  111   a  function as passing portions for flexible portions  151   c  through which an inner ring portion  151   a  of the damper  150  and an outer ring portion  151   b  are connected to each other. The two discontinued portions  111   b ′ on the short-side direction center line of the yoke outer side-wall  111   a  function as passing portions for the flexible portions  151   c  through which the inner ring portion  151   a  of the damper  150  and the outer ring portion  151   b  are connected to each other, and also as voice coil lead-wire drawn out ports. The two through holes  167  on the longitudinal direction center line of the frame  160  are inside the two discontinued portions  111   b  on the longitudinal direction center line of the yoke outer sidewall  111   a.  In the two discontinued portions  111   b ′ on short-side direction center line of the yoke outer sidewall  111   a,  the two through holes  167 ′ on the short-side direction center line of the frame  160  are disposed in the both portions of the bottom plate  161  outside and inside the yoke outer side-wall  111   a.    
     A horizontal upper step face  168  which functions as an upper support face for the vibration system  120  is disposed in the upper inner face of the outer sidewall  162 . A horizontal lower step face  169  which functions as a lower support face for the vibration system  120  is disposed in the lower inner face of the outer sidewall  162 . The lower step face  169  is formed to be slightly smaller than the upper step face  168 . 
     The yoke-integral type frame  160  is formed by performing a press process on one flat metal plate (magnetic material), and has an axisymmetric structure in which the short-side direction center line is set as the symmetric axis. 
     The magnet  112  is configured by a long columnar permanent magnet. The pole piece  113  is configured by an oval flat metal plate (magnetic material). The magnet  112  is bonded and fixed to the inner bottom face of the yoke  111 , and the pole piece  113  is bonded and fixed to the upper face of the magnet  112 , thereby configuring the oval magnetic circuit  110  of the internal magnet type. The magnetic circuit  110  forms an oval magnetic gap  114  between an upper portion of the yoke outer sidewall  111   a  and the pole piece  113 . 
     The voice coil  121  is formed into an oval cylindrical shape by winding a copper wire or the like around the outer peripheral face of an oval cylindrical voice coil bobbin  121   a  made of a plastic film or the like. The voice coil lead wires  121   b  for electrically connecting the voice coil  121  to the external connection terminals  130  are connected to both end portions of the winding, respectively. The voice coil lead wires  121   b  are drawn out from two places of a lower end portion of the voice coil  121  and on the short-side direction center line of the voice coil  121 . 
     The diaphragm  122  is configured by a thin film such as a plastic film of polyethylene terephthalate (PET), polyetherimide (PEI), polyimide (PI), or the like. The diaphragm  122  has an oval diaphragm middle portion  123  which covers the upper end opening of the voice coil  121 , and the diaphragm edge portion  124  which surrounds the whole circumference of the diaphragm middle portion  123 , and in which the outer shape is formed into a rectangular shape so as to coincide with that of the frame  160 . The diaphragm  122  is formed by separately forming the diaphragm middle portion  123  and the diaphragm edge portion  124 , and then bonding and fixing together an outer peripheral edge portion of the diaphragm middle portion  123  and an inner peripheral edge portion of the diaphragm edge portion  124 . Alternatively, the diaphragm  122  may be formed by integrally forming the diaphragm middle portion  123  and the diaphragm edge portion  124 . A honeycomb-like reinforcement rib  125  is formed on the whole face of the diaphragm middle portion  123 , so that the whole face of the diaphragm middle portion  123  is uniformly reinforced, and the diaphragm middle portion  123  is provided with necessary strength (rigidity) while the diaphragm middle portion  123  is thinned (finally flattened from a dome-like shape to a flat plate-like shape), thereby realizing thinning of the other speaker  101 . The illustrated reinforcement rib  125  is formed into a bulge-like shape in which the upper face of the diaphragm middle portion  123  is convex and the lower face is concave. Alternatively, the reinforcement rib may be formed into a groove-like shape in which the upper face of the diaphragm middle portion  123  is concave and the lower face is convex. A surface member  127  which is configured by a metal foil such as an aluminum foil, or a thin film of a plastic film or the like such as PET, PEI, or PI is bonded to each of the upper and lower faces of the diaphragm middle portion  123  as a reinforcing member which further reinforces the diaphragm middle portion  123 . Alternatively, the surface member  127  may be bonded to only one of the upper and lower faces of the diaphragm middle portion  123 . It is matter of course that the surface member  127  may be used as a reinforcing member for the diaphragm middle portion  23  in the speaker  1  in Embodiment 1. A rectangular diaphragm ring  126  which is made of a metal such as brass, and which functions as a washer is bonded and fixed to the rear side of an outer peripheral edge portion of the diaphragm edge portion  124 . 
     The vibration system  120  is configured by bonding and fixing the rear side of the interface between the diaphragm middle portion  123  of the diaphragm  122  and the diaphragm edge portion  124  to an upper end portion of the voice coil bobbin  121   a,  and hangingly fixing the voice coil  121  to the rear side of the interface between the diaphragm middle portion  123  of the diaphragm  122  and the diaphragm edge portion  124  through the voice coil bobbin  121   a.    
     The vibration system  120  is held by coupling its upper end portion to the frame  160  which is the stationary portion of the speaker  101  by means of the diaphragm edge portion  124 . Namely, the outer peripheral edge portion of the diaphragm edge portion  124  is bonded and fixed through the diaphragm ring  126  to the upper step face  168  which is disposed on the inner face of the upper portion of the outer sidewall  162  as the upper support face for the vibration system  120 , whereby the diaphragm  122  is disposed there so as to cover the upper opening of the frame  160 . The voice coil  121  is inserted and placed in the magnetic gap  114  from the upper side. The diaphragm edge portion  124  plays a role of holding the vibration system  120  to the correct position to realize accurate vibration of the vibration system  120 . 
     The external connection plate  131  is a printed circuit board in which two external connection terminals  130  are integrally disposed in an insulated state. The plate is attached to the recess portion  165  of the frame  160 , and one-end sides of the external connection terminals  130  are exposed through the through holes  166  to the both end portions of the inner bottom face of the raised bottom portion  164 , respectively. The other end sides of the external connection terminals  130  are exposed to the rear side of the external connection plate  131  in a substantially flush manner, and electrically connected to an external circuit (printed circuit board) of an electronic apparatus such as a portable telephone onto which the other speaker  101  is mounted. 
     The baffle  140  is formed by applying a pressing process on a metal flat plate, into a celled rectangular tubular shape which is shallower than the frame  160 , and fitted to the upper opening of the frame  160  to cover and protect the the diaphragm  122 . The lower end of the outer side wall of the baffle  140  presses and fixes from the upper side the outer peripheral edge portion of the diaphragm edge portion  124  and the diaphragm ring  126  against the step face  168 . A front sound hole  141  having a substantially same shape as the diaphragm middle portion  123  is disposed in the top plate of the baffle  140 . To the outer top face of the baffle  140  and the outer bottom face of the frame  160 , damping cloth (not shown) having air permeability is bonded in order to cover the front sound hole  141  and rear sound holes (through holes  167 ,  167 ′) which are formed in the faces, adjust the acoustic performance of the other speaker  101 , and prevent dust from entering the interior of the other speaker  101 . 
     The other speaker  101  includes: the magnetic circuit  110  having the yoke  111 , the magnet  112 , and the pole piece  113 ; the vibration system  120  having the voice coil  121  and diaphragm  122  which are connected to each other through the voice coil bobbin  121   a;  and the frame  160  which holds the magnetic circuit  110  and the vibration system  120 , and the voice coil  121  is placed in the magnetic gap  114 , thereby configuring the dynamic other speaker  101 . 
     In the dynamic other speaker  101 , when, in a state where the voice coil lead wires  121   b  are connected to the external connection terminals  130  inside the frame  160 , a current is supplied from the external circuit to the voice coil  121  through the external connection terminals  130  and the voice coil lead wires  121   b,  the voice coil  121  is caused to perform vertical piston motion or vibrate by an interaction between the magnetic fluxes which are directed in a substantially horizontal direction in the magnetic gap  114 , and the current flowing through the voice coil  121 . The vibration is transmitted to the diaphragm  122  by the voice coil bobbin  121   a,  and the diaphragm middle portion  123  vibrates while setting the diaphragm edge portion  124  as a fulcrum, thereby generating a sound. Namely, the speaker converts electricity into a sound. 
     The damper  150  is disposed in the other speaker  101  in order to cooperate with the diaphragm edge portion  124  to play a role of holding the vibration system  120  to a correct position to realize accurate vibration of the vibration system  120 . The damper is configured so that the voice coil lead wires  121   b  are laid on one surface to be guided to the external connection terminals  130 . 
     As shown in  FIGS. 6A ,  6 B, and  6 C, the damper body  151  which exerts a damper function, and a part of which functions also as a pair of lead portions for guiding the two voice coil lead wires  121   b  to the external connection terminals  130  to which the wires are to be connected is disposed in the damper  150 . The damper body  151  is placed in one plane. The damper  150  is formed by performing a punching process on one sheet-like member (non-magnetic material) such as a plastic film of polyethylene terephthalate (PET), polyetherimide (PEI), polyimide (PI), or the like, and has a planar structure. 
     In the damper body  151 , an inner ring portion  151   a  that is a movable portion which is coupled to a lower end portion of the voice coil bobbin  121   a  opposite to the diaphragm  122 , an outer ring portion  151   b  that is a fixed portion coupled to the frame  160  which is a stationary portion of the other speaker  101 , and flexible portions  151   c  through which the inner ring portion  151   a  and the outer ring portion  151   b  are connected to each other are disposed. The damper body is configured so as to support the vibration system  120  with respect to the frame  160 . 
     The inner ring portion  151   a  is formed into an oval annular member which has a constant width over the whole circumference, so as to cause the outer peripheral end face of the inner ring portion  151   a  to contact with the inner peripheral face of the voice coil bobbin  121   a,  or the one surface of the inner ring portion  151   a  to contact with the lower end face of the voice coil bobbin  121   a.    
     The outer ring portion  151   b  is formed into a rectangular annular member which has a constant width that is substantially equal to that of the inner ring portion  151   a,  over the whole circumference, and which is concentric with the inner ring portion  151   a,  so as to be superimposed on the lower step face  169  which is disposed in the lower inner face of the outer sidewall  162 , and which functions as the lower support face for the vibration system  120 . 
     The flexible portions  151   c  are configured by a plurality (in the illustrated example, eight) of flexurally deformable plate spring-like members which are bent in a crank-like manner in one plane, and which have a constant width that is substantially equal to the widths of the inner ring portion  151   a  and the outer ring portion  151   b  over the whole circumference. Intermediate portions of the flexible portions  151   c  are placed along an oval virtual line which is drawn between the inner ring portion  151   a  and the outer ring portion  151   b  and outside the yoke outer sidewall  111   a,  and which is concentric with the inner ring portion  151   a  and the yoke outer sidewall  111   a.  Inward ends of the flexible portions  151   c  are coupled to the outer peripheral edge of the inner ring portion  151   a,  and the inward other ends of the flexible portions  151   c  are coupled to the inner peripheral edge of the outer ring portion  151   b.  The flexible portions  151   c  cause the inner ring portion  151   a  and the outer ring portion  151   b  to be connected to each other at a plurality (in the illustrated example, eight) of places which are shifted in the circumferential direction of the damper body  151 . 
     The connection pattern between the inner ring portion  151   a  and the outer ring portion  151   b  through the flexible portions  151   c  is formed into a shape in which, since the inner ring portion  151   a  is placed inside the yoke outer sidewall  111   a  and the outer ring portion  151   b  is placed outside the yoke outer sidewall  111   a,  the flexible portions  151   c  couples between the inner ring portion  151   a  and the outer ring portion  151   b  through the discontinued portions  111   b,    111   b ′ that are disposed in a total of four places, i.e., two places on the longitudinal direction center line of the yoke outer sidewall  111   a,  and two places on the short-side direction center line. 
     Furthermore, the connection pattern between the inner ring portion  151   a  and the outer ring portion  151   b  through the flexible portions  151   c  is formed into a shape which does not cause the damper performance to be unbalanced depending on the circumferential position of the damper body  151 . Namely, the pattern has a symmetrical shape such as an axisymmetrical shape in which the center line in the longitudinal direction center line (in  FIG. 6A , the vertical direction) or short-side direction center line (in  FIG. 6A , the lateral direction) of the damper body  151  is set as the symmetrical axis, or a point (rotational) symmetrical shape in which the center of the damper body  151  is set as the symmetry center. In the illustrated example, the pattern has an axisymmetrical shape in which any of the center lines in the longitudinal direction and short-side direction of the damper body  151  can be set as the symmetrical axis, and a 180-degree point symmetrical shape in which the center of the damper body  151  is set as the symmetry center (however, excluding tongue pieces  151   d ). 
     Furthermore, the connection pattern between the inner ring portion  151   a  and the outer ring portion  151   b  through the flexible portions  151   c  is formed into a shape in which two specific flexible portions  151   c ′ of the flexible portions  151   c  function also as a pair of lead portions for guiding the two voice coil lead wires  121   b  to the external connection terminals  130  to which the wires are to be connected. Namely, the two voice coil lead wires  121   b  are drawn out from the two places on the short-side direction center line of the voice coil  121  that are directly above two places on the short-side direction center line of the inner ring portion  151   a,  and the external connection terminals  130  are exposed through the through holes  166  in the both end portions of the inner bottom face of the raised bottom portion  164  which are directly below both corner portions in the end portion in the longitudinal direction (in  FIGS. 6A and 7 , the upper end portion) of the outer ring portion  151   b.  Therefore, the connection pattern between the inner ring portion  151   a  and the outer ring portion  151   b  through the flexible portions  151   c  is formed into a shape in which the two specific flexible portions  151   c ′ of the flexible portions  151   c  connect the two places on the short-side direction center line of the inner ring portion  151   a  to the both corner portions in the end portion in the longitudinal direction of the outer ring portion  151   b.    
     Specifically, the flexible portions  151   c  are configured by a total of eight portions configured by: two portions which connect one place in the one end side (in  FIG. 6A , the upper end side) in the longitudinal direction of the inner ring portion  151   a  of the two places on the center line in the longitudinal direction of the inner ring portion  151   a,  to one end side (upper end side) of the two sides in the longitudinal direction of the outer ring portion  151   b;  two portions which connect one place in the other end side (in  FIG. 6A , the lower end side) in the longitudinal direction of the inner ring portion  151   a  to the other end side (in  FIG. 6A , the lower end side) of the two sides in the longitudinal direction of the outer ring portion  151   b;  two portions which connect one place in the one side (in  FIG. 6A , the left side) in the short-side direction of the inner ring portion  151   a  of the two places of the short-side direction center line of the inner ring portion  151   a,  to the both end side (in  FIG. 6A , upper and lower end sides) of the one side (in  FIG. 6A , the left side) in the longitudinal direction of the outer ring portion  151   b;  and two portions which connect one place in the other side (in  FIG. 6A , the right side) in the short-side direction of the inner ring portion  151   a  to the both end side (in  FIG. 6A , upper and lower end sides) of the other side (in  FIG. 6A , the right side) in the longitudinal direction of the outer ring portion  151   b.  The flexible portions  151   c  connect between the inner ring portion  151   a  which is placed inside the yoke outer sidewall  111   a,  and the outer ring portion  151   b  which is placed outside the yoke outer sidewall  111   a,  through the discontinued portions  111   b,    111   b ′ that are disposed in a total of four places, i.e., two places on the longitudinal direction center line of the yoke outer sidewall  111   a,  and two places on the short-side direction center line, so as not to cause the damper performance to be unbalanced depending on the circumferential position of the damper body  151 . In the flexible portions  151   c,  the two specific flexible portions  151   c ′ function also as a pair of lead portions for guiding the two voice coil lead wires  121   b  to the external connection terminals  130  to which the wires are to be connected. The two specific flexible portions  151   c ′ are configured by: one flexible portion which connects one place of one side (in  FIG. 6A , the left side) in the short-side direction to the one end side (in  FIG. 6A , the upper end side) of one side (in  FIG. 6A , the left side) in the longitudinal direction of the outer ring portion  151   b,  through the discontinued portion  111   b ′ which is disposed in one place in one side of the short-side direction of the two places on the short-side direction center line of the yoke outer sidewall  111   a  of the two places of the short-side direction center line of the inner ring portion  151   a;  and one flexible portion which connects one place of the other side (in  FIG. 6A , the right side) in the short-side direction to the one end side (in  FIG. 6A , the upper end side) of the other side (in  FIG. 6A , the right side) in the longitudinal direction of the outer ring portion  151   b,  through the discontinued portion  111   b ′ which is disposed in one place in the other side of the short-side direction of the two places on the short-side direction center line of the yoke outer sidewall  111   a.    
     The pair of tongue pieces  151   d  which are formed continuously with end portions of the two specific flexible portions  151   c ′ on the side of the outer ring portion  151   b  are formed in the both corner portions that are directly above the both end portions of the inner bottom face of the raised bottom portion  164  from which the external connection terminals  130  are exposed through the through holes  166 , and that are in one end portion (in  FIGS. 6A and 7 , the upper end portion) in the longitudinal direction of the outer ring portion  151   b  of the damper body  151 . Through holes  151   e  for passing the voice coil lead wires  121   b  therethrough are disposed in the tongue pieces  151   d.    
     Bonding layers  151   f  (the hatched portions in  FIG. 6A ) are disposed on one surfaces (upper faces) of the two specific flexible portions  151   c ′ in order to bond and fix the voice coil lead wires  121   b.  Each of the bonding layers  151   f  has a linear shape which is continuous from a basal end portion which is coupled to the inner ring portion  151   a  to the through hole  151   e  of the corresponding tongue piece  151   d  that is formed continuously with the end portion on the side of the external connection terminals  130 , or a broken line like shape in which one or more interrupted parts are formed. The bonding layers  151   f  are formed by, for example, application of an adhesive material. 
     The damper  150  has as a whole an axisymmetric structure in which the longitudinal-direction center line of the damper body  151  is set as the symmetrical axis. 
     As shown in  FIGS. 7 to 9 , in the vibration system  120  in which the upper end portion is connected and held by the diaphragm edge portion  124  to the upper step face  168  that is disposed as the upper support face for the vibration system  120  in the upper inner face of the outer side-wall  162  of the frame  160  that is a stationary portion of the other speaker  101 , the lower end is connected and held by the damper  150  to the lower step face  169  that is disposed as the lower support face for the vibration system  120  in the lower inner face of the outer sidewall  162  of the frame  160  that is a stationary portion of the speaker  101 . Namely, the damper body  151  is horizontally stretched between the lower end portion of the voice coil bobbin  121   a  and the lower step face  169  that is disposed as the lower support face for the vibration system  120  in the lower inner face of the outer sidewall  162  of the frame  160 , by: bonding and fixing the outer peripheral end face of the inner ring portion  151   a  to the inner peripheral face of the voice coil bobbin  121   a;  or bonding and fixing the one surface (upper face) of the inner ring portion  151   a  to the lower end face of the voice coil bobbin  121   a,  and superimposing the outer ring portion  151   b  on the lower step face  169  that is disposed as the lower support face for the vibration system  120  in the lower inner face of the outer sidewall  162  of the frame  160 , to be boned and fixed thereto, whereby the damper body  151  is enabled to exert a damper function. 
     At this time, the flexible portions  151   c  connect between the inner ring portion  151   a  which is placed inside the yoke outer sidewall  111   a,  and the outer ring portion  151   b  which is placed outside the yoke outer sidewall  111   a,  through the discontinued portions  111   b,    111   b ′ that are disposed in a total of four places, i.e., the two places on the longitudinal direction center line of the yoke outer sidewall  111   a,  and the two places on the short-side direction center line, so as not to cause the damper performance to be unbalanced depending on the circumferential position of the damper body  151 . In the flexible portions  151   c,  the two specific flexible portions  151   c ′ configured by: one flexible portion which connects one place of one side (in  FIG. 7 , the left side) in the short-side direction of two places on the short-side direction center line of the inner ring portion  151   a,  to the one end side (in  FIG. 7 , the upper end side) of one side (in  FIG. 7 , the left side) in the longitudinal direction of the outer ring portion  151   b;  and one flexible portion which connects one place of the other side (in  FIG. 7 , the right side) in the short-side direction to the one end side (in  FIG. 7 , the upper end side) of the other side (in  FIG. 7 , the right side) in the longitudinal direction of the outer ring portion  151   b  guide the two voice coil lead wires  121   b  to the external connection terminals  130  to which the wires are to be connected. 
     Namely, the configuration where the two voice coil lead wires  121   b  which are drawn out from the two places of the lower end portion of the voice coil  121  that are directly above the end portions of the two specific flexible portions  151   c ′ on the side of the inner ring portion  151   a,  and on the short-side direction center line of the voice coil  121  are bonded and fixed to the bonding layers  151   f  disposed on the one surfaces (upper faces) of the two specific flexible portions  151   c ′ allows the two voice coil lead wires  121   b  to be bent into a substantially L-like shape along the two specific flexible portions  151   c ′, and to be guided to the both corner portions in the one end portion (in  FIG. 7 , the upper end portion) in the longitudinal direction of the outer ring portion  151   b  that are directly above the both end portions of the raised bottom portion  164  from which the external connection terminals  130  are exposed through the through holes  166 , while passing through the discontinued portions  111   b  which are disposed in two places on the short-side direction center line of the yoke outer sidewall  111   a,  and between the yoke outer sidewall  111   a  and the outer sidewall  162  of the frame  160 . In this way, the process of laying the two voice coil lead wires  121   b  by means of forming to the external connection terminals  130  to which the wires are to be connected is realized not in the air of the interior of the other speaker  101 , but in a part of the damper body  151 , i.e., on the one surfaces of the two specific flexible portions  151   c′.    
     When the voice coil lead wires  121   b  are bonded and fixed to the bonding layers  151   f  of the two specific flexible portions  151   c ′, enough slacks are provided between the end portions of the voice coil lead wires  121   b  on the drawn out side from the voice coil  121 , and the portions where the two specific flexible portions  151   c ′ are bonded and fixed to the bonding layers  151   f,  in order to allow and not to impeded the voice coil  121  to vibrate. 
     After the laying process by means of forming, the two voice coil lead wires  121   b  are connected by soldering or spot welding  180  to one end sides of the external connection terminals  130  which are exposed in the both end portions of the inner bottom face of the raised bottom portion  164  through the through holes  166  that are disposed in the both end portions of the bottom plate  161   a  of the raised bottom portion  164 , through the through holes  151   e  of the tongue pieces  151   d  that are formed continuously with the end portions the two specific flexible portions  151   c ′ on the side of the outer ring portion  151   b.    
     As described above, the damper  150  is used in the speaker including: the magnetic circuit  110  having the yoke  111 , the magnet  112 , and the pole piece  113 ; the vibration system  120  having the voice coil  121  and diaphragm  122  which are connected to each other through the voice coil bobbin  121   a;  and the frame  160  which holds the magnetic circuit  110 , the vibration system  120 , and the external connection terminals  130 , the voice coil  121  being placed in the magnetic gap  114 , and the voice coil lead wires  121   b  are guided to the external connection terminals  130  while being laid on the one surface. The embodiment has: the inner ring portion  151   a  which is a movable portion that is coupled to the end portion of the voice coil bobbin  121   a  opposite to the diaphragm  122 ; the outer ring portion  151   b  which is a fixed portion coupled to the frame  160  that is the stationary portion of the speaker  101 ; and the plurality of flexible portions  151   c  through which the inner ring portion  151   a  and the outer ring portion  151   b  are connected to each other. The damper body  151  which supports the vibration system  120  with respect to the frame  160  is disposed. The flexible portions  151   c  includes the specific flexible portions  151   c ′ which function also as a pair of lead portions for guiding the two voice coil lead wires  121   b  to the external connection terminals  130  to which the wires are to be connected. The process of laying the voice coil lead wires  121   b  by means of forming is realized not in the air of the interior of to the frame  160  but in a part of the damper body  151 , i.e., on the one surfaces of the two specific flexible portions  151   c ′. Therefore, the process of laying the voice coil lead wires  121   b  by means of forming can be performed easily and properly, the forming of the voice coil lead wires  121   b  can be stabilized, and the positional accuracy of the voice coil lead wires  121   b  with respect to the external connection terminals  130  can be improved, so that improvement of the productivity of the speaker  101  can be realized. The flex resistance of the voice coil lead wires  121   b  can be improved, and also improvement of the input resistance characteristics of the speaker  101  can be realized. Particularly, the damper body  151  supports the vibration system  120  with respect to the frame  160 . Therefore, the magnet  112  of the magnetic circuit  110  can be enlarged to enhance the strength of the magnetic circuit  110 , whereby the sensitivity of the speaker  101  can be improved (as compared with the speaker  1  of Embodiment 1). 
     Furthermore, the lower end of the vibration system  120  which has the maximum distance from the diaphragm edge portion  124  is supported by the damper body  151 , and hence a high damper performance can be obtained. Moreover, two points, i.e., the upper and lower ends of the vibration system  120  are supported by the diaphragm edge portion  124  and the damper body  151 , and hence the vibration system  120  can produce more stable and accurate vibration. Therefore, the input resistance characteristics of the speaker  101  can be further improved. 
     Moreover, the damper body  151  is placed in the one plane, and the process of laying the voice coil lead wires  121   b  by means of forming is realized on the one flat surfaces of the specific flexible portions  151   c ′. Therefore, the process of laying the voice coil lead wires  121   b  by means of forming can be performed easily and properly, so that further improvement of the productivity of the speaker  101 , further thinning of the speaker  101 , and further improvement of the input resistance characteristics of the speaker  101  can be realized. 
     Furthermore, the damper  150  which has a planar structure formed by performing a punching process on one sheet-like member, and which can realize improvement of the productivity, thinning, and improvement of the input resistance characteristics of the speaker  101  can be economically obtained. 
     Furthermore, the speaker  101  includes the damper  150  of the embodiment, and hence it is possible to realize a thin speaker which has a high productivity, a high input resistance, a high output, and a high sensitivity. 
     DESCRIPTION OF REFERENCE NUMERALS   
       1 ,  101  speaker 
       10 ,  110  magnetic circuit 
       11 ,  111  yoke 
       12 ,  112  magnet 
       13 ,  113  pole piece 
       14 ,  114  magnetic gap 
       20 ,  120  vibration system 
       21 ,  121  voice coil 
       21   a,    121   a  voice coil bobbin 
       21   b,    121   b  voice coil lead wire 
       22 ,  122  diaphragm 
       30 ,  130  external connection terminal 
       50 ,  150  damper 
       51 ,  151  damper body 
       51   a  outer ring portion (movable portion) 
       51   b  inner ring portion (fixed portion) 
       51   c  flexible portion 
       52  lead portion 
       60 ,  160  frame 
       151   a  inner ring portion (movable portion) 
       151   b  outer ring portion (fixed portion) 
       151   c  flexible portion 
       151   c ′ specific flexible portion (lead portion)