JP2009147414A - Loudspeaker apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a loudspeaker apparatus which can be made thin and compact and has high input resistance and high sound quality. <P>SOLUTION: The loudspeaker apparatus has an external magnetic type repulsing magnetic circuit 1, a frame 2 and a vibrating body 3. The external magnetic type repulsing magnetic circuit 1 is constituted so that a plate 11 formed in a nearly annular shape is held between magnets 12 and 13 formed in a nearly annular shape and disposed having the polarities opposed to each other. The vibrating body 3 has a diaphragm 21, a voice coil 24 and a voice coil bobbin 23. The frame 2 supports the vibrating body 3 and external magnetic type repulsing magnetic circuit 1. In this speaker apparatus, the voice coil bobbin 23 is formed nearly cylindrically. Further, a heat dissipation body 4 is loosely inserted into the voice coil bobbin 23. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a speaker device provided with a repulsive magnetic circuit configured by sandwiching one plate made of a magnetic material with two magnets arranged so that the same poles face each other.

  In a conventional speaker device having a repulsive magnetic circuit, a magnet and a center plate have a substantially annular shape, and inner and outer voice coils are arranged in respective repulsive magnetic fields generated on the inner and outer peripheries of the center plate, and are driven synchronously. Some are configured to do so. A repulsive magnetic circuit composed of a magnet and a center plate is installed on a holder (yoke) made of a non-magnetic material, and the pole portion of this holder is loosely inserted into the center hole of the repulsive magnetic circuit. An air gap is formed between the inner peripheral surface of the lens and the pole portion (see, for example, Patent Document 1).

Japanese Patent No. 3195516 (Claim 1, [0009] to [0013], FIG. 1)

  In the conventional speaker device described above, a pole portion is formed at a substantially central portion of the holder (yoke), and this pole portion is loosely inserted into the center hole of the repulsive magnetic circuit. Therefore, since the thickness of the entire speaker device is increased by the thickness of the holder (yoke), there is a problem that it is difficult to reduce the thickness and weight of the speaker device. Further, in the above-described conventional speaker device, there is no allowance for the clearance between the voice coil, the pole portion, and the magnet, so there is a limit on the thickness of the voice coil bobbin around which the voice coil is wound, and high input resistance and high sound quality are achieved. There was a problem that it was difficult to plan. Further, in the conventional speaker device described above, the back side of the speaker device (opposite to the sound radiation direction) is sealed with a holder (yoke), so that the air heated in the voice coil bobbin is difficult to move, There is a problem that it is difficult to design an efficient speaker device with low resistance, low heat dissipation efficiency, and high input resistance.

  This invention is made | formed in view of the situation mentioned above, and makes it an example of a subject to solve the above problems, and provides the speaker apparatus which can solve these subjects. With the goal.

  In order to solve the above-mentioned problem, a speaker device according to claim 1 is configured to surround a diaphragm, a voice coil bobbin, a vibrating body having a voice coil wound around the voice coil bobbin, and the voice coil bobbin. An outer magnet type repulsive magnetic circuit configured by sandwiching a plate configured in a substantially ring shape with a magnet configured in a substantially ring shape and disposed so that the same poles face each other, and the vibrator and the outer magnet The voice coil bobbin has a substantially cylindrical shape, and a heat radiator is loosely inserted inside the voice coil bobbin.

Embodiment 1 FIG.
1 is a cross-sectional view showing a schematic configuration of a speaker device according to Embodiment 1 of the present invention, and FIG. 2 is a rear view of the speaker device shown in FIG. 1 with a dustproof net 14 removed. The speaker device includes a magnetic circuit 1, a frame 2, a vibrating body 3, and a heat radiating body 4. The magnetic circuit 1 is a repulsive type constituted by sandwiching a plate 11 between two magnets 12 and 13 arranged so that the same poles face each other, and is an external magnetic type. The plate 11 is made of a soft magnetic material such as iron (for example, low carbon steel). The plate 11 has a substantially annular shape.

  The magnets 12 and 13 are made of, for example, permanent magnets such as neodymium-based, samarium-cobalt-based, alnico-based, and ferrite-based magnets. The magnets 12 and 13 have the same substantially annular shape and have the same dimensions. The outer diameter of each of the magnets 12 and 13 is slightly smaller than the outer diameter of the plate 11. The plate and the magnets 12 and 13 are fixed by, for example, an adhesive or the like so that the center axes in the thickness direction of each other overlap each other.

  In this magnetic circuit 1, a dust-proof net 14 is fixed to the back surface of the magnet 12 on the back surface side (opposite to the sound radiation direction) of the speaker device, for example, with an adhesive or the like, as shown in FIG. The dustproof net 14 has a substantially trapezoidal cross section, and the surface is processed into a fine mesh. A flange (outer ring portion) 14b having a substantially annular shape is formed integrally with the main body 14a around the periphery of the dustproof net 14. The upper surface of the flange 14b is fixed to the rear surface of the magnet 12 with, for example, an adhesive.

  The dust net 14 is made of, for example, ferrous metal, non-ferrous metal or an alloy thereof, synthetic resin, or the like. Examples of the iron-based metal include pure iron, oxygen-free steel, and silicon steel. Examples of the non-ferrous metal include aluminum, magnesium, and zinc. As synthetic resins, for example, glass fibers or fibrillated thermotropic liquid crystal polyester resins are added as reinforcing fillers to thermoplastic resins such as olefins such as polypropylene, ABS (acrylonitrile, butadiene, styrene), and polyethylene terephthalate. There are things that become. The dust-proof net 14 is formed by, for example, drawing a ferrous metal, die-casting a non-ferrous metal or an alloy thereof, or injection-molding a synthetic resin.

  The dustproof net 14 is for preventing foreign matters such as dust from flowing into the speaker device from the outside. That is, when there is a large difference in atmospheric pressure between the inside and outside of the speaker device, the vibration characteristics of the vibrating body 3 are significantly deteriorated. Therefore, usually, the back side of the speaker device is opened, or a through hole is provided in order to allow air to enter and exit from a substantially central portion such as a yoke. However, if a foreign substance flows in through the back side of the speaker device or through the through hole, there is a possibility that the narrow magnetic gap (magnetic gap) G is adversely affected. Therefore, the inflow of such foreign matters is prevented in advance by the dust-proof net 14, thereby improving the reliability.

  On the other hand, in the magnetic circuit 1, the frame 2 is fixed to the front surface of the magnet 13 on the front surface side (acoustic radiation direction) of the speaker device by, for example, an adhesive. The frame 2 is made of, for example, a ferrous metal, a non-ferrous metal or an alloy thereof, a synthetic resin, or the like. Examples of the iron-based metal include pure iron, oxygen-free steel, and silicon steel. Examples of the non-ferrous metal include aluminum, magnesium, and zinc. As synthetic resins, for example, glass fibers or fibrillated thermotropic liquid crystal polyester resins are added as reinforcing fillers to thermoplastic resins such as olefins such as polypropylene, ABS (acrylonitrile, butadiene, styrene), and polyethylene terephthalate. There are things that become. The frame 2 is formed by, for example, drawing a ferrous metal, die casting a non-ferrous metal or an alloy thereof, or injection molding a synthetic resin.

  The frame 2 includes three layers, a first layer 2a, a second layer 2b, and a third layer 2c. The first layer 2a and the second layer 2b are connected via a step 2d. That is, the frame 2 is configured by integrally forming the first layer 2a, the stepped portion 2d, the second layer 2b, and the third layer 2c. Each of the first layer 2a and the second layer 2b has a substantially trapezoidal cross-sectional shape. On the other hand, the third layer 2c has a substantially cylindrical shape. The outer diameter of the second layer 2b is larger than the outer diameter of the first layer 2a, and the outer diameter of the third layer 2c is larger than the outer diameter of the second layer 2b.

  A through hole (not shown) having a substantially circular shape is formed in the approximate center of the first layer 2a. The front surface of the magnet 13 constituting the magnetic circuit 1 is fixed to the periphery of the through hole with, for example, an adhesive. As a result, the frame 2 supports the magnetic circuit 1. On the side surface of the second layer 2b, a plurality of openings 2ba having a substantially fan-like planar shape are formed. In the example of FIG. 2, four openings 2ba are shown. Although not shown, the frame 2 opens upward in the third layer 2c. The frame 2 supports a vibrating body 3 described later on the inner bottom portion 2ca and the step portion 2d of the third layer 2c.

  The vibrating body 3 includes a diaphragm 21, an edge 22, a voice coil bobbin 23, a voice coil 24, a damper 25, and a center cap 26. The planar shape of the diaphragm 21 has a substantially annular shape. The longitudinal cross-sectional shape of the diaphragm 21 has a substantially conical shape (cone shape).

  Examples of the material of the diaphragm 21 include paper, a woven fabric using fibers, a knitted fabric using fibers, a nonwoven fabric, a woven fabric using fibers impregnated with a binding resin made of a silicone resin, a metal material, There are synthetic resins, acrylic foams, hybrid materials made of synthetic resins and metals, and the like. Examples of the metal material include aluminum, titanium, duralumin, beryllium, magnesium, and alloys thereof. Examples of the synthetic resin include polypropylene, polyethylene, polystyrene, polyethylene terephthalate, polymethyl methacrylate, polycarbonate, epoxy resin, and the like. The acrylic foam is made from, for example, methyl methacrylate, methacrylic acid, styrene, maleic anhydride, and methacrylamide.

  A through hole 21aa having a substantially circular planar shape is formed in the inner peripheral edge 21a of the diaphragm 21. An outer peripheral surface in the vicinity of the upper end of the voice coil bobbin 23 having a substantially cylindrical shape is fixed to the through hole 21aa with an adhesive or the like. As a material of the voice coil bobbin 23, for example, an organic fiber, an inorganic fiber, or a metal material can be adopted. Specifically, for example, a fiber impregnated with a resin material such as a phenol resin impregnated glass fiber or a polyimide resin impregnated glass fiber, a metal foil such as aluminum (Al) or duralumin, a resin film such as polyimide or the like is used for the voice coil bobbin 23. It can be adopted as a material.

  A voice coil 24 is wound around the outer peripheral surface near the lower end of the voice coil bobbin 23 as shown in FIG. Both ends of the voice coil 24 are drawn out along the voice coil bobbin 23 and the diaphragm 21, and are electrically connected to a pair of lead wires (not shown) near the inner periphery of the diaphragm 21, for example. A magnetic gap G is formed between the magnetic circuit 1 including the plate 11 and the magnets 12 and 13 and the voice coil bobbin 23 around which the voice coil 24 is wound. The pair of lead wires (not shown) is made of, for example, a tinsel wire that is strong against bending and is formed by twisting a plurality of thin electric wires.

  The center cap 26 is formed of, for example, a spherical plate having an outer diameter substantially equal to the inner diameter of the magnets 12 and 13. In the vicinity of the inner peripheral edge 21 a of the diaphragm 21, the center cap 26 is fixed with an adhesive or the like so that the upper side of the voice coil bobbin 23 is blocked and the front side (acoustic radiation direction) of the speaker device is convex. . As described above, the center cap 26 is connected to the diaphragm 21 (or the voice coil bobbin 23 and the diaphragm 21) to reinforce the structural strength of the diaphragm 21 and the voice coil bobbin 23, and the diaphragm 21 and the voice coil bobbin. 23 divided vibrations are suppressed as much as possible.

  Further, since the center cap 26 vibrates integrally with the diaphragm 21, the center cap 26 radiates a part of the acoustic energy (mainly the high sound range), and corrects the phase of the interference of the sound wave caused by the shape of the diaphragm 21. It has the role of adjusting the acoustic characteristics of the device. Thereby, the center cap 26 corrects the influence of the acoustic characteristics caused by the through hole 21aa formed in the inner peripheral edge 21a of the diaphragm 21 as necessary.

  On the other hand, an edge 22 is formed integrally with the diaphragm 21 on the outer peripheral edge of the diaphragm 21. The edge 22 has appropriate compliance and rigidity. The edge 22 has a substantially roll shape in which the planar shape has a substantially annular shape and the longitudinal cross-sectional shape protrudes to the front side (acoustic radiation direction) of the speaker device. The outer peripheral edge of the edge 22 is fixed to the inner bottom portion 2ca of the third layer 2c constituting the frame 2 with an adhesive or the like. As described above, the diaphragm 21 is connected to the frame 2 through the edge 22. That is, the edge 22 elastically supports the diaphragm 21 with respect to the frame 2.

  The damper 25 has a substantially annular shape in plan view. The damper 25 has appropriate compliance and rigidity. Corrugation is formed in the damper 25 concentrically with the inner peripheral edge 21 a of the diaphragm 21. That is, the cross-sectional shape of the damper 25 has a plurality of convex portions and concave portions. The damper 25 is formed, for example, by impregnating a cloth with a phenolic resin or the like, a solution made of a phenolic resin and an organic solvent, and the like, and by heat molding. The outer peripheral edge of the damper 25 is fixed to the step 2d constituting the frame 2 with an adhesive or the like. On the other hand, the inner peripheral edge of the damper 25 is an outer peripheral surface in the vicinity of the upper end of the voice coil bobbin 23, and is fixed to the lower part of the inner peripheral edge 21 a of the diaphragm 21 with an adhesive or the like. As described above, the diaphragm 21 is connected to the frame 2 via the damper 25. That is, the damper 25 elastically supports the diaphragm 21 with respect to the frame 2.

  Accordingly, the damper 25 elastically moves the diaphragm 21, the center cap 26, the voice coil bobbin 23, and the voice coil 24 together with the edge 22 at predetermined positions of the speaker device in a stationary state of the speaker device (a state where the speaker device is not driven). Supportive. The damper 25 elastically holds the voice coil 24 and the voice coil bobbin 23 at a predetermined position where they do not come into contact with the parts constituting the magnetic circuit 1 such as the plate 11 and the magnets 12 and 13.

  The damper 25 also has a role of elastically supporting the center cap 26, the diaphragm 21, the voice coil bobbin 23, and the voice coil 24 along the vibration direction in the driving state of the speaker device.

  The heat radiating body 4 is loosely inserted inside the voice coil bobbin 23 constituting the vibrating body 3 described above. The radiator 4 has a substantially cylindrical shape. The outer diameter of the radiator 4 is slightly smaller than the inner diameter of the voice coil bobbin 23, for example. The length of the radiator 4 is substantially equal to the length of the voice coil bobbin 23 or shorter than the length of the voice coil bobbin 23. In the example of FIG. 1, the length of the radiator 4 is about two thirds of the length of the voice coil bobbin 23. The lower end of the radiator 4 is fixed to the front surface of the main body 14a of the dust-proof net 14 with, for example, an adhesive.

  The heat radiating body 4 is made of a material having a higher thermal conductivity than the magnetic bodies (plate 11, magnets 12 and 13) constituting the magnetic circuit 1. Examples of the material of the radiator 4 include aluminum (Al), copper (Cu), zinc (Zn), tungsten (W), and molybdenum (Mo). The thermal conductivity (0 ° C.) of aluminum (Al) is 237 W / m · K, oxygen-free copper (Cu) is 391 W / m · K, tough pitch copper (Cu) is 389.3 W / m · K, zinc (Zn) is 117 W / m · K, tungsten (W) is 174 W / m · K, and molybdenum (Mo) is 139 W / m · K. On the other hand, the thermal conductivity (0 ° C.) of iron (Fe), which is one of the materials of the plate 11 and the magnets 12 and 13, is 83.5 W / m · K.

  In the speaker device having the above configuration, when an audio signal (audio current) is supplied, the audio current is supplied to the voice coil 24 via a pair of lead wires (not shown). On the other hand, the magnetic flux based on the magnet 12 constituting the magnetic circuit 1 and the magnetic flux based on the magnet 13 are combined toward the inner peripheral edge of the plate 11 in the radial direction after being combined to the approximate center in the thickness direction of the plate 11. The voice coil bobbin 23 and the voice coil 24 are transmitted in a direction perpendicular to the central axis direction of the voice coil bobbin 23 and the voice coil 24.

  Therefore, the driving force in the direction of the central axis of the speaker device is induced in the voice coil 24 based on the electromagnetic force (Lorentz force) between the combined magnetic flux based on the magnets 12 and 13 and the audio current passed through the voice coil 24. Is done. This driving force is transmitted to the diaphragm 21 via the voice coil bobbin 23. The vibration plate 21 receives the action of the driving force, vibrates while being elastically supported by the edge 22 and the damper 25, and radiates a sound wave corresponding to the sound current toward a space in the front surface (acoustic radiation direction).

  As described above, when a voice signal (sound current) is supplied, the voice coil 24 generates heat, so that heat is transmitted to the voice coil bobbin 23, and the air in the voice coil bobbin 23 is further heated. The air heated in the voice coil bobbin 23 touches the surface of the heat radiating body 4 having a high thermal conductivity and is cooled. In Embodiment 1 of the present invention, since the radiator 4 has a substantially cylindrical shape, it has a larger surface area that is in contact with air, has better heat dissipation efficiency, and is lighter than a block shape. is there.

  Thus, according to the first embodiment of the present invention, unlike the conventional speaker device, it is not necessary to provide a yoke on the back side (the opposite side to the acoustic radiation direction) of the speaker device. The overall thickness of the apparatus can be designed to be thin, and the overall weight of the speaker apparatus can be reduced. Further, according to Embodiment 1 of the present invention, since the thickness of the voice coil bobbin 23 can be increased, it is possible to achieve high input resistance and high sound quality.

  Furthermore, according to the first embodiment of the present invention, the radiator 4 is loosely inserted in the voice coil bobbin 23. Therefore, the air heated in the voice coil bobbin 23 is cooled by the heat radiating body 4 and can be designed to move easily and have a low mechanical resistance and an efficient speaker device. As a result, higher input resistance can be achieved.

Embodiment 2. FIG.
3 is a sectional view showing a schematic configuration of the speaker device according to Embodiment 2 of the present invention, and FIG. 4 is a rear view showing the schematic configuration of the speaker device shown in FIG. 3 and 4, the same reference numerals are given to the portions corresponding to the respective portions in FIGS. 1 and 2, and the description thereof is omitted. The speaker device shown in FIGS. 3 and 4 is different from the speaker device shown in FIGS. 1 and 2 in that the dustproof net 14 is removed, and the voice coil bobbin 31 and the radiator 4 are replaced with the voice coil bobbin 31 and The heat radiator 32 is newly provided.

  The difference between the voice coil bobbin 31 and the voice coil bobbin 23 is that a radiating fin 31 a is formed on the outer peripheral surface of the lower end of the voice coil bobbin 31 integrally or separately from the voice coil bobbin 31. The heat radiating fin 31a has a substantially annular shape in plan view, and has a flange (outer ring portion) extending horizontally toward the direction of the magnet 12. The voice coil bobbin 31 is made of the same material as the voice coil bobbin 23 described above.

  The radiator 32 has a substantially circular planar shape and a substantially inverted T-shaped cross section. That is, the heat radiator 32 is configured by integrally forming a base portion (a projecting portion) 32a having a substantially disc shape and a column portion 32b having a substantially columnar shape and erected substantially at the center of the base portion 32a. . The outer diameter of the base 31a is slightly smaller than the outer diameter of the magnets 12 and 13, for example. On the other hand, the outer diameter of the column portion 31 b is slightly smaller than the inner diameter of the voice coil bobbin 31. The radiator 32 is made of the same material as the radiator 4 described above. The upper surface of the outer peripheral edge of the base portion 32a constituting the radiator 32 is fixed to the back surface of the magnet 12 with, for example, an adhesive.

  In the speaker device having the above configuration, when a voice signal (sound current) is supplied, the voice coil 24 generates heat, so that heat is transmitted to the voice coil bobbin 31 and the air in the voice coil bobbin 31 is heated. The air heated in the voice coil bobbin 31 touches the surface of the heat radiating body 32 having a high thermal conductivity and is cooled. At this time, part of the heat generated by the voice coil 24 is transmitted to the magnets 12 and 13. Among these, the heat transmitted to the magnet 12 is transmitted to the base portion 32a constituting the heat radiating body 32 fixed to the back surface of the magnet 12 and cooled.

  At the same time, since the voice coil bobbin 31 moves up and down by the driving force induced in the voice coil 24, the radiating fins 31a formed on the outer peripheral surface of the lower end of the voice coil bobbin 31 also move up and down at the same time. As a result, the air heated in the voice coil bobbin 31 is agitated by the radiating fins 31a to forcibly form a flow. The agitated air is discharged out of the magnetic circuit 1. At the same time, fresh air outside the magnetic circuit 1 is also sucked into the magnetic circuit 1 and circulated together with the air inside, so that cooling is performed efficiently.

  Thus, according to the second embodiment of the present invention, unlike the conventional speaker device, it is not necessary to provide a yoke on the back side (the opposite side to the sound radiation direction) of the speaker device. A heat radiator 32 composed of a column part 32 b loosely inserted in the voice coil bobbin 31 and a base part 32 a fixed to the back surface of the magnet 12 can be provided. As a result, the air heated in the voice coil bobbin 31 is cooled by the column portion 32b, and the heat transmitted to the magnet 12 is radiated through the base portion 32a. As a result, the heat radiation efficiency is increased as compared with the conventional case, and higher input resistance can be achieved.

  Further, according to the second embodiment of the present invention, since the heat dissipating fins 31a are formed on the outer peripheral surface of the lower end of the voice coil bobbin 31, the air heated in the voice coil bobbin 31 is stirred by the heat dissipating fins 31a and magnetically It is discharged out of the circuit 1. As a result, the heat radiation efficiency can be increased by the synergistic effect of the heat radiator 32 and the heat radiation fin 31a. Furthermore, according to the second embodiment of the present invention, since the voice coil bobbin 31 can be made thicker, higher input resistance and higher sound quality can be achieved.

Embodiment 3 FIG.
5 is a cross-sectional view showing a schematic configuration of the speaker device according to Embodiment 3 of the present invention, and FIG. 6 is a rear view showing the schematic configuration of the speaker device shown in FIG. FIG. 7 is an enlarged sectional view showing a schematic configuration of the voice coil bobbin 41 constituting the speaker device shown in FIG. 5 and FIG. 6, parts corresponding to those in FIG. 3 and FIG. The speaker device shown in FIGS. 5 and 6 is different from the speaker device shown in FIGS. 3 and 4 in that a voice coil bobbin 41 and a radiator 42 are newly provided in place of the voice coil bobbin 31 and the radiator 32. It is.

  The difference between the voice coil bobbin 41 and the voice coil bobbin 31 is that, instead of the heat radiating fins 31a, a plurality of plural intervals are provided from the vicinity of the lower end of the inner peripheral surface of the voice coil bobbin 41 to approximately the center with a predetermined interval as shown in FIGS. The point is that the radiating fins 41a are formed integrally with the voice coil bobbin 41 or separately. Each of the heat radiation fins 41 a has a substantially annular shape in plan view, and has a flange (outer ring portion) that extends horizontally toward the central axis of the voice coil bobbin 41. In the example of FIG. 7, four radiating fins 41a are formed. The voice coil bobbin 41 is made of the same material as the voice coil bobbins 23 and 31 described above.

  The radiator 42 is made of the same material as the radiator 4 and the radiator 32 described above. Further, the radiator 42 has the same outer shape as the radiator 32, that is, a base 42a having a substantially disc shape like the base 32a, and a substantially columnar shape like the column 32b, and is erected substantially at the center of the base 42a. The pillar portion 42b is integrally formed. Further, the radiator 42 has the same dimensions as the radiator 32. However, the heat radiator 42 is provided with a plurality of vent holes 42c extending from the approximate center of the base portion 42a to the upper end of the column portion 42b. Each of the vent holes 42c has a substantially cylindrical shape. In the example of FIG. 7, four vent holes 42c are formed.

  In the speaker device having the above configuration, when the audio signal (audio current) is supplied, the voice coil 24 generates heat, so that heat is transmitted to the voice coil bobbin 41, and the air in the voice coil bobbin 41 is further heated. The air heated in the voice coil bobbin 41 touches the surface of the radiator 42 having a high thermal conductivity and is cooled. In this case, the base portion 42a of the heat radiating body 42 is provided with a plurality of vent holes 42c extending from substantially the center to the upper end of the column portion 42b. Therefore, the surface area of the entire radiator 42 is increased by the inner peripheral surface of the plurality of vent holes 42c, so that the cooling effect is increased.

  At the same time, since the voice coil bobbin 41 moves up and down by the driving force induced in the voice coil 24, the radiating fins 41a formed on the inner peripheral surface of the lower end of the voice coil bobbin 41 also move up and down at the same time. As a result, the air heated in the voice coil bobbin 41 is agitated by the radiating fins 41a to forcibly form a flow. The agitated air is discharged out of the magnetic circuit 1. At the same time, fresh air outside the magnetic circuit 1 is also sucked into the magnetic circuit 1 and circulated together with the air inside, so that cooling is performed efficiently.

  As described above, according to the third embodiment of the present invention, it is not necessary to provide a yoke on the back side (opposite to the sound radiation direction) of the speaker device as in the conventional speaker device. A heat radiator 42 composed of a column part 42 b loosely inserted in the voice coil bobbin 41 and a base part 42 a fixed to the back surface of the magnet 12 can be provided. Thereby, the air heated in the voice coil bobbin 41 is cooled by the column part 42b, and the heat transmitted to the magnet 12 is dissipated through the base part 42a. As a result, the heat radiation efficiency is increased as compared with the conventional case, and higher input resistance can be achieved.

  Further, according to the third embodiment of the present invention, since the plurality of heat radiation fins 41a are formed from the vicinity of the lower end of the inner peripheral surface of the voice coil bobbin 41 to the substantially center, the air heated in the voice coil bobbin 41 is radiated. It is stirred by the fins 41a and discharged out of the magnetic circuit 1. As a result, the heat radiation efficiency can be increased by the synergistic effect of the heat radiator 42 and the heat radiation fin 41a. Furthermore, according to Embodiment 3 of the present invention, since the thickness of the voice coil bobbin 41 can be increased, higher input resistance and higher sound quality can be achieved.

As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to these embodiments, and the design can be changed without departing from the scope of the present invention. Is included in the present invention.
For example, in the above-described third embodiment, the example in which the plurality of heat radiation fins 23a are formed integrally with or separate from the voice coil bobbin 41 from the vicinity of the lower end of the inner peripheral surface of the voice coil bobbin 41 to the substantially center has been described. . For example, the radiating fin may be provided with a slight gap between the lower winding portion of the voice coil 24 or may be provided so as to be in contact with the lower winding portion of the voice coil 24. Further, the flange surface of the radiating fin may have a flat shape or a wing shape, the center portion may bulge upward or downward, and the center portion may bulge upward or downward. The bulging portion may be formed at a required interval so as to be orthogonal to the protruding portion. For details of the structure of the radiating fin, refer to, for example, Japanese Patent Application Laid-Open No. 2006-5819.

Further, in the above-described third embodiment, an example is shown in which the radiator 42 has four vent holes 42c each having a substantially cylindrical shape. However, the present invention is not limited to this, and the number of vent holes 42c is as follows. One, two, three, or five or more may be used, and the shape of the vent holes 42c may be a substantially triangular prism shape, a substantially quadrangular prism shape, or a five or more polygonal column shape, and the shape of each vent hole 42c may be different. .
Further, in each of the above-described embodiments, the diaphragm 21 has an example in which the longitudinal cross-sectional shape has a cone shape. However, the present invention is not limited to this, and the vertical cross-sectional shape protrudes to the front side (the sound wave emission side). It may have a substantially dome shape.

In each of the above-described embodiments, a magnetic fluid may be provided between the magnetic circuit 1 and the voice coil bobbins 23, 31, 41, or the voice coil 24. By providing the magnetic fluid in this way, it is possible to increase the electromagnetic force acting on the voice coil 24, to dissipate heat by transmitting the heat (Joule heat) generated in the voice coil 24 to the plate 11, and the like.
Further, in each of the above-described embodiments, the example in which the planar shape of the speaker device has a substantially circular shape has been shown, but the present invention is not limited to this, and the planar shape of the speaker device is substantially rectangular, substantially elliptical, or The polygonal shape may be exhibited. Further, in each of the above-described embodiments, since the planar shape of the speaker device has a substantially circular shape, the example in which the plate 11 and the magnets 12 and 13 have a substantially annular shape has been shown. It is not limited. For example, when the planar shape of the speaker device has a substantially rectangular shape, the plate 11 and the magnets 12 and 13 may have a substantially rectangular ring shape.

In each of the above-described embodiments, the magnetic circuit 1 is composed of one plate 11 having a substantially ring shape and two magnets 12 and 13 each having a substantially ring shape. An example is shown, but the present invention is not limited to this. Any or all of the plate 11 and the magnets 12 and 13 may be composed of a plurality of plate materials or a plurality of magnets having a substantially arc shape or a substantially rectangular shape.
Further, in each of the above-described embodiments, the damper 25 is shown as an example in which corrugation is formed concentrically with the inner peripheral edge 21a of the diaphragm 21, but the invention is not limited to this, and the damper 25 is formed with corrugation. You don't have to.
In addition, each of the above-described embodiments can divert each other's technology as long as there is no particular contradiction or problem in the purpose, configuration, or the like.

It is sectional drawing which shows schematic structure of the speaker apparatus which concerns on Embodiment 1 of this invention. It is a rear view in the state which removed the dustproof net of the speaker apparatus shown in FIG. It is sectional drawing which shows schematic structure of the speaker apparatus which concerns on Embodiment 2 of this invention. It is a rear view which shows schematic structure of the speaker apparatus shown in FIG. It is sectional drawing which shows schematic structure of the speaker apparatus which concerns on Embodiment 3 of this invention. It is a rear view which shows schematic structure of the speaker apparatus shown in FIG. It is an expanded sectional view which shows schematic structure of the voice coil bobbin which comprises the speaker apparatus shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Magnetic circuit, 2 ... Frame, 2a ... 1st layer, 2b ... 2nd layer, 2ba ... Opening part, 2c ... 3rd layer, 2ca ... Inner bottom part, 2d ... Step part, 3 ... Vibrating body, 4,32 , 42 ... radiator, 11 ... plate, 12, 13 ... magnet, 14 ... dust-proof net, 21 ... diaphragm, 21aa ... inner peripheral edge, 21aa ... through hole, 22 ... edge, 23, 31, 41 ... voice coil bobbin, 24 ... Voice coil, 25 ... Damper, 26 ... Center cap, 31a, 41a ... Radiating fin, 32a, 42a ... Base, 32b, 42b ... Column, 42c ... Vent

Claims (6)

A vibrating body having a diaphragm, a voice coil bobbin, and a voice coil wound around the voice coil bobbin;
An outer magnet type repulsive magnetic circuit configured by sandwiching a plate configured in a substantially ring shape so as to surround the voice coil bobbin with a magnet configured in a substantially ring shape and arranged so that the same poles face each other;
A frame for supporting the vibrating body and the outer magnet type repulsive magnetic circuit;
The voice coil bobbin is configured in a substantially cylindrical shape,
A speaker device, wherein a heat radiator is loosely inserted in the voice coil bobbin. The speaker device according to claim 1, wherein the heat radiating body has a vent hole. The speaker device according to claim 1, wherein the heat dissipator is configured in a substantially cylindrical shape. The speaker device according to any one of claims 1 to 3, wherein the heat dissipating member has a protruding portion for contacting the magnet at a lower end portion. The speaker device according to any one of claims 1 to 4, wherein the voice coil bobbin has a heat radiating fin formed outside an end opposite to a sound radiation direction. The speaker device according to any one of claims 1 to 5, wherein a heat radiating fin is formed inside the voice coil bobbin.

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