Speaker device

Abstract

To provide a speaker device which has an assemblability at a manufacturing, and can improve vibration damping properties while maintaining a quality of a low sound reproduction.SOLUTION: A speaker device 1 comprises: a first voice coil 11; a second voice coil 21 arranged to an outside of a radial direction of the first voice coil 11; a first dumper part 14 that supports the first voice coil 11 to a frame 3; and a second dumper part 22 that supports the second voice coil 21 to the frame 3. The first dumper part 14 includes a concave part 142 that is separated to the second voice coil 21 from the other part in the first dumper part 14 on an extension line of a vibration direction of the second voice coil 21.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a speaker device. [Background technology]

[0002] Speaker devices that reproduce sound by vibrating a diaphragm are widely used in vehicles, for example, automobile cabins, to reproduce sounds such as music and voices. Patent Document 1 describes a technique in which a second driving means is arranged facing in the opposite direction to a first driving means having a diaphragm as a sound emitting member, and the vibration of the first driving means is offset by a reaction force.

[0003] Patent document 2 describes a speaker device that includes a main body that performs the primary function of radiating sound waves to the sound-emitting side, and a vibration suppression section that suppresses vibrations that occur in the magnetic circuit due to vibrations of the vibration system of the main body when the device is driven. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Special Publication No. 60-6157 [Patent Document 2] Japanese Patent Application Laid-Open No. 2006-13587 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the speaker device of Patent Document 1 is taller (length in the vibration direction) than a typical speaker with only a first driving means. Furthermore, the speaker device of Patent Document 2 requires two driving means (speaker units) and requires a significantly increased number of processes, resulting in poor assembly. Furthermore, the speaker device of Patent Document 2 shares a single hollow disk-shaped magnet in the magnetic circuit, which reduces the length of the damper in the vibration suppression unit, preventing the vibration suppression unit from achieving sufficient amplitude to offset the vibration of the main body. Furthermore, increasing the amplitude may cause interference between the diaphragm of the main body and the voice coil of the vibration suppression unit. Furthermore, the speaker device of the second embodiment of Patent Document 2 has the voice coil of the main body positioned on the outside, reducing the amplitude of the main body, making it unsuitable for a woofer that reproduces low frequencies at high output. In particular, speaker devices such as woofers that reproduce low and deep bass frequencies require relatively large driving means, which require ingenuity to install in vehicles with limited installation space. Therefore, space-saving and slimmer designs are desired.

[0006] The present disclosure has been made to solve these problems, and its purpose is to provide a speaker device that is easy to assemble during manufacturing and that can improve vibration-damping characteristics while maintaining the quality of audio reproduction, and that can achieve both improved vibration-damping characteristics and a thinner speaker device. [Means for solving the problem]

[0007] The present disclosure has been made to solve at least part of the above-mentioned problems, and can be realized in the following aspects.

[0013] The speaker device according to this aspect includes a first voice coil, a second voice coil disposed radially outward of the first voice coil, a first damper supporting the first voice coil on a frame, a second damper supporting the second voice coil on the frame, and a magnetic circuit having a first magnet and a second magnet, the first magnet and the second magnet being arranged side by side in the vibration direction of the first voice coil and being disposed radially inward of the second voice coil, the magnetic circuit having a first magnetic member, an intermediate magnetic member, and a second magnetic member, the intermediate magnetic member having a plate-shaped first bottom portion and a magnetic pole extending from the periphery of the first bottom portion. the first magnet is stacked on the intermediate magnetic member, and the first magnetic member is stacked on the first magnet, a first magnetic gap is formed between the first magnetic member and the first cylindrical member, in which the first voice coil is disposed; the second magnetic member is stacked on the second magnetic member, and a second magnetic gap is formed between the second magnetic member and the first cylindrical member, in which the first voice coil is disposed; the second magnetic member is stacked on the second magnetic member, and the first magnetic gap is formed between the second magnetic member and the intermediate magnetic member, in which the second voice coil is disposed; The second magnetic gap is formed between the first bottom and the second cylindrical portion. do.

[0015] The intermediate magnetic member of the speaker device may have a protrusion that protrudes radially outward beyond the outer circumferential surface of the first cylindrical portion and forms the second magnetic gap.

[0016] The second magnet of the speaker device may have a larger radial size than the first magnet. [Effects of the Invention]

[0026] The speaker device according to the present disclosure using the above means improves assembly during manufacturing, and can improve vibration-damping characteristics while maintaining the quality of audio reproduction.Furthermore, it is possible to achieve both improved vibration-damping characteristics and a thinner design. [Brief explanation of the drawings]

[0027] [Figure 1]1 is a perspective view of a speaker device according to a first embodiment of the present disclosure. [Figure 2] 1 is a side cross-sectional view of a speaker device according to a first embodiment of the present disclosure. [Figure 3] FIG. 2 is an explanatory diagram showing the arrangement of magnetized surfaces of a magnet and the direction of the magnetic field of a magnetic circuit according to the first embodiment of the present disclosure. [Figure 4] 3 is an explanatory diagram showing the amplitude of a driver of the speaker device according to the first embodiment of the present disclosure. FIG. [Figure 5] FIG. 10 is a perspective view of a speaker device according to a second embodiment of the present disclosure. [Figure 6] FIG. 10 is a side cross-sectional view of a speaker device according to a second embodiment of the present disclosure. [Figure 7] FIG. 10 is an explanatory diagram showing the arrangement of magnetized surfaces of a magnet and the direction of the magnetic field of a magnetic circuit according to a second embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0028] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0029] (First embodiment) Fig. 1 is a perspective view of a speaker device 1 according to a first embodiment of the present disclosure. Fig. 2 is a side cross-sectional view in an XZ plane passing through a central axis O1 of the speaker device 1. The configuration of the speaker device 1 according to the first embodiment will be described below with reference to these figures.

[0030] The speaker device 1 of this embodiment is a speaker mounted, for example, in a vehicle door, and its main parts are axially symmetrical with respect to a central axis O1 as shown in FIG. 2. The speaker device 1 includes a housing (enclosure) (not shown), a frame 3 attached to the housing, a first driving unit 10 attached to the frame 3, a second driving unit 20 attached to the frame 3, and a magnetic circuit 30 having a magnetic body and a magnet. In the following description, a direction parallel to the central axis O1 is referred to as an axial direction, and within the axial direction, a direction from the second driving unit 20 to the first driving unit 10 is referred to as a forward direction, and a direction from the first driving unit 10 to the second driving unit 20 is referred to as a rearward direction. Furthermore, a direction radiating perpendicularly outward from the central axis O1 is referred to as a radial direction. The speaker device 1 radiates sound forward from the first driving unit 10. The speaker device 1 is, for example, a woofer or subwoofer, and is capable of reproducing low-frequency sounds with a large input.

[0031] The first driving section 10 includes a first voice coil 11, a diaphragm 12, an edge section 13, a first damper section 14, and a center cap 15.

[0032] The first voice coil 11 is composed of a cylindrical first bobbin 111 coaxial with the central axis O1 and a first coil 112 wound around the outer circumferential surface of the first bobbin 111, and is disposed in the center of the speaker device 1. The diaphragm 12 has a circular hole at its center coaxial with the central axis O1, and is cone-shaped extending radially outward and forward from the inner circumferential edge of the circular hole, and is a sound-emitting member disposed radially outside the first voice coil 11. The inner circumferential edge of the diaphragm 12 is connected to the outer circumferential surface of the first voice coil 11. An edge portion 13 is formed between the outer circumferential edge of the diaphragm 12 and the frame 3. The edge portion 13 is annular, forming a recess with an inverted U-shaped cross section, with its inner circumferential edge overlapping the outer circumferential edge of the diaphragm 12, and its outer circumferential edge is connected to the frame 3.

[0033] The first damper section 14 is an elastic body having an annular disk shape with a circular hole at its center that is coaxial with the central axis O1 and that extends radially outward from the inner circumferential edge where the circular hole is formed, and is disposed radially outward from the first voice coil 11 and behind the diaphragm 12. The first damper section 14 has a corrugated cross section as a whole, the detailed shape of which will be described later. The first damper section 14 has an inner circumferential edge connected to the outer circumferential surface of the first voice coil 11 and an outer circumferential edge connected to the frame 3. The first damper section 14 connects the first voice coil 11 and the frame 3, supporting the first voice coil 11 so that it can vibrate in the direction of the central axis O1. The vibration direction of the first voice coil 11 is the same as the axial direction.

[0034] The frame 3 has a concave cross section with a diameter that gradually decreases toward the rear, and the rear end of the frame 3 is connected to a second yoke 35 (described later) of the magnetic circuit 30. A center cap 15, which is a sound-emitting member, is disposed in the center of the first driving unit 10 so as to cover a portion of the center of the first voice coil 11 and the diaphragm 12. The outer periphery of the center cap 15 is connected to a portion of the top surface (front surface) of the diaphragm 12.

[0035] The second driving section 20 includes a second voice coil 21 and a second damper section 22.

[0036] The second voice coil 21 is composed of a second bobbin 211 that is cylindrical and coaxial with the central axis O1 and has a larger diameter than the first bobbin 111, and a second coil 212 that is wound around the outer surface of the second bobbin 211, and is arranged concentrically with the first voice coil 11 at the center of the speaker device 1 and radially outward from the first voice coil 11.

[0037] The second damper section 22 is composed of two dampers 22a and 22b, which are support members, and a spacer 23 for maintaining the axial distance between the two dampers 22a and 22b. In the following description, when it is necessary to distinguish between the two dampers, the one of the two dampers 22a and 22b that is located closer to the diaphragm 12 will be referred to as damper 22a, and the other will be referred to as damper 22b. Each of the dampers 22a and 22b is a disk-shaped elastic body that has a circular hole at its center that is coaxial with the central axis O1 and extends radially outward from the inner circumferential edge where the circular hole is formed. The dampers 22a and 22b are arranged side by side in the axial direction, with the spacer 23 sandwiched between them, radially outward from the second voice coil 21. Specifically, the rear surface of the outer circumferential edge of the damper 22a is connected to the front surface of the spacer 23, and the front surface of the outer circumferential edge of the damper 22b is connected to the rear surface of the spacer 23. The inner peripheral edges of the dampers 22a and 22b are connected to the outer peripheral surface of the second voice coil 21. Furthermore, the rear surface of the outer peripheral edge of the damper 22b is connected to the frame 3. The second damper section 22 is connected to the second voice coil 21 on the inner peripheral side and to the frame 3 on the outer peripheral side, thereby connecting the second voice coil 21 and the frame 3 and supporting the second voice coil 21 so that it can vibrate in the direction of the central axis O1. The vibration direction of the second voice coil 21 is the same as the axial direction. The dampers 22a and 22b have corrugated cross sections and are identical in shape when mounted (their cross-sectional shapes overlap when moved parallel to the axial direction). This allows the distance between the dampers 22a and 22b to be set small, improving assembly ease.

[0038] The inner peripheries of the diaphragm 12 and the first damper section 14 are adhesively fixed to the outer periphery of the first bobbin 111 with an adhesive. The outer peripheries of the diaphragm 12 and the first damper section 14 are adhesively fixed to the frame 3 with an adhesive. The inner peripheries of the dampers 22a and 22b of the second damper section 22 of the second driving section 20 are adhesively fixed to the outer periphery of the second bobbin 211 with an adhesive. The outer peripheries of the dampers 22a and 22b are adhesively fixed to the frame 3 with an adhesive. The other connecting sections of the first driving section 10 and the second driving section 20 are also basically adhesively fixed with an adhesive.

[0039] The magnetic circuit 30 includes a top plate 31 (first magnetic member), a first magnet 32, a first yoke 33 (intermediate magnetic member), a second magnet 34, and a second yoke 35 (second magnetic member), and is disposed at the center of the speaker device 1 and behind the first driving unit 10. These components are stacked coaxially in the vibration direction of the first voice coil 11 and the second voice coil 21, in the order of the second magnet 34, the first yoke 33, the first magnet 32, and the top plate 31, starting from the rearmost second yoke 35. The top plate 31, the first yoke 33, and the second yoke 35 are magnetic members. The magnetic circuits of the first driving unit 10 and the second driving unit 20 are configured as a single magnetic circuit 30, and by stacking the magnetic circuit 30 from the rear, assembly in the manufacturing process is facilitated. The first magnet 32 ​​and the second magnet 34 are both disposed radially inward of the second voice coil 21. In this case, the radial size of the second magnet 34 is larger than the radial size of the first magnet 32. This makes it possible to increase the magnetic flux density of the second magnetic gap G2a (described later) even in the second voice coil 21, which has a larger diameter and is heavier than the first voice coil 11. Note that the radial sizes of the first magnet 32 ​​and the second magnet 34 may be the same, or may have a different size relationship from that in the embodiment.

[0040] The second yoke 35 has a cylindrical shape with one end open and a bottom. The second yoke 35 has a disk-shaped second bottom portion 35a coaxial with the central axis O1, a second cylindrical portion 35b extending from the outer periphery of the second bottom portion 35a, and a cylindrical second protrusion portion 35c protruding forward from the center of the second bottom portion 35a. In this embodiment, as shown in FIG. 2, the second yoke 35 has a recess in the bottom surface (rear surface) of the second bottom portion 35a for weight reduction and centering during processing. The second magnet 34 has a cylindrical shape coaxial with the central axis O1 and approximately the same diameter as the second protrusion portion 35c, and is stacked on the top surface (front surface) of the second protrusion portion 35c. In addition, an attachment flange is formed on the outer periphery of the front end of the second cylindrical portion 35b, and the attachment flange is connected to the rear end of the frame 3.

[0041] The first yoke 33 is essentially a smaller-diameter version of the second yoke 35, and includes a disk-shaped first bottom portion 33a coaxial with the central axis O1, a first cylindrical portion 33b extending from the periphery of the first bottom portion 33a, and a cylindrical first protrusion 33c protruding forward from the center of the first bottom portion 33a. The first yoke 33 is stacked on the top surface (front surface) of the second magnet 34. The first magnet 32 ​​is cylindrical, coaxial with the central axis O1, and has approximately the same diameter as the first protrusion 33c, and is stacked on the top surface (front surface) of the first protrusion 33c. The top plate 31 is cylindrical, slightly larger in diameter than the first magnet 32, and is stacked on the top surface (front surface) of the first magnet 32.

[0042] The second cylindrical portion 35b extends forward up to near the top surface (front surface) of the first bottom portion 33a. The first bottom portion 33a has a protrusion 33d that protrudes radially outward from the outer circumferential surface of the first cylindrical portion 33b, i.e., toward the second cylindrical portion 35b.

[0043] The first cylindrical portion 33b extends to the top surface (front surface) of the top plate 31. The outer diameters of the top plate 31, the first magnet 32, and the first protrusion 33c are each smaller than the inner diameter of the first cylindrical portion 33b. As shown in FIG. 2, an annular first gap G1 is formed radially inside the first cylindrical portion 33b between the inner peripheral surface of the first cylindrical portion 33b and the outer peripheral surfaces of the top plate 31, the first magnet 32, and the first protrusion 33c, and the first cylindrical portion 33b extends from the front end of the first cylindrical portion 33b to the top surface (front surface) of the first bottom portion 33a. A magnetic field that is substantially uniform in the circumferential direction is generated in a first magnetic gap G1a formed between the outer peripheral surface of the top plate 31 and the inner peripheral surface of the first cylindrical portion 33b in the first gap G1.

[0044] Similarly, the outer diameters of the first bottom portion 33a, the second magnet 34, and the second protrusion 35c are each smaller than the inner diameter of the second cylindrical portion 35b. As shown in Fig. 2, an annular second gap G2 is formed radially inside the second cylindrical portion 35b between the inner peripheral surface of the second cylindrical portion 35b and the outer peripheral surfaces of the first bottom portion 33a, the second magnet 34, and the second protrusion 35c, and the second cylindrical portion 35b extends from the tip of the second cylindrical portion 35b to the top surface (front surface) of the second bottom portion 35a. A magnetic field that is substantially uniform in the circumferential direction is generated in a second magnetic gap G2a formed by the outer peripheral surface of the first bottom portion 33a (the outer peripheral surface of the protrusion 33d) and the inner peripheral surface of the second cylindrical portion 35b within the second gap G2. In this embodiment, by adjusting the protrusion amount of the protrusion portion 33d of the first bottom portion 33a, the spacing of the second magnetic gap G2a can be narrowed, thereby increasing the magnetic flux passing through the second magnetic gap G2a and reducing the leakage magnetic flux.

[0045] Figure 3 is an explanatory diagram showing the arrangement of the magnetized surfaces of magnets and the direction of the magnetic field of the magnetic circuit according to the first embodiment of the present invention. Specifically, it is an explanatory diagram showing the magnetic polarity arrangement of the magnetized surfaces of the first magnet 32 ​​and the second magnet 34 within the laminated structure of the magnetic circuit 30, and the direction of the magnetic field of the magnetic circuit 30 generated by this arrangement. Note that in Figure 3, the hatching indicating the cross section of the magnetic circuit 30 has been removed to make the explanatory arrows and text easier to see.

[0046] The first magnet 32 ​​and the second magnet 34 are, for example, permanent magnets, and are magnetized in the axial direction. That is, if the disk surface (magnetized surface) on one side of the first magnet 32 ​​and the second magnet 34 is an S pole, the disk surface (magnetized surface) on the other side is an N pole. In the magnetic circuit 30, when stacked as shown in FIG. 3 , one magnetized surface of the first magnet 32 ​​(the front magnetized surface, N pole) is connected to the bottom surface (rear surface) of the top plate 31, and the other magnetized surface of the first magnet 32 ​​(the rear magnetized surface, S pole) is connected to the top surface (front surface) of the first protrusion 33c of the first yoke 33. One magnetized surface (front magnetized surface, S pole) of the second magnet 34 is connected to the bottom surface (rear surface) of the first bottom portion 33a of the first yoke 33, which is a surface different from the surface to which the first magnet 32 ​​of the first yoke 33 is connected, and the other magnetized surface (rear magnetized surface, N pole) of the second magnet 34 is connected to the top surface (front surface) of the second protrusion 35c of the second yoke 35. In this manner, the magnetic circuit 30 has the first yoke 33 connected to the first magnet 32 ​​and connected to the second magnet 34 on a surface different from the surface of the first magnet 32. In the speaker device 1 of the first embodiment, the magnetic circuit 30 forms a repulsive magnetic circuit in which the first magnet 32 ​​and the second magnet 34 are arranged so that like poles (S poles in FIG. 3 ) face each other in the magnetic circuit via the first yoke 33, which is a magnetic member. Note that the magnetic polarities of the first magnet 32 ​​and the second magnet 34 may be reversed, so that the N poles face each other. Furthermore, the first magnet 32 ​​and the second magnet 34 may be arranged with the same poles facing each other, or with opposite poles facing each other, and the magnetization direction is not limited. For example, the magnetization directions of the first magnet 32 ​​and the second magnet 34 may be reversed, with the south pole facing the north pole. This is true whether an internal magnet type or an external magnet type is used for the magnetic circuit.

[0047] 3, two flows of magnetic flux are generated in the magnetic circuit 30 of the speaker device 1: a flow of magnetic flux (arrow A) from the top plate 31 through the first magnetic gap G1a toward the first cylindrical portion 33b and first convex portion 33c of the first yoke 33, and a flow of magnetic flux (arrow B) from the second convex portion 35c of the second yoke 35 through the second cylindrical portion 35b and second magnetic gap G2a toward the first bottom portion 33a of the first yoke 33. In this case, the magnetic field directions are aligned at the first bottom portion 33a where the two arrows A and B overlap, so that by using two magnets (the first magnet 32 ​​and the second magnet 34), the magnetic fields generated in the first magnetic gap G1a and the second magnetic gap G2a may be reinforced. Furthermore, the first bottom portion 33a, which is the portion where the two arrows A and B overlap, can also be used as a plate for forming the second magnetic gap G2a, which allows for a thinner, lighter device and a reduced number of parts.

[0048] A portion of the rear side of the first bobbin 111 is disposed in the first gap G1, and a first coil 112 is wound around the outer peripheral surface of the rear side disposed at the position of the first magnetic gap G1a. The first bobbin 111 is supported by the frame 3 via the first damper unit 14 and is capable of vibrating in the axial direction. Although not shown, the first coil 112 is connected to a signal transmission circuit. Therefore, a first driving force (first electromagnetic force) is generated in the first coil 112 in the axial direction due to the action of an electric signal from the signal transmission circuit and the magnetic field of the first magnetic gap. The first driving force then vibrates the first bobbin 111 together with the first coil 112, vibrating the first drive unit 10. Furthermore, the vibration of the diaphragm 12 together with the first bobbin 111 radiates sound. At this time, a first excitation force is generated in the speaker device 1 in response to the vibration of the first drive unit. This first excitation force causes the housing fixed to the speaker device 1 to vibrate.

[0049] A portion of the rear side of the second bobbin 211 is disposed within the second gap G2, and a second coil 212 is wound around the outer peripheral surface of the rear side, which is disposed at the position of the second magnetic gap G2a. The second coil 212 is wound in the same direction as the first coil 112. Here, "wound in the same direction" means that, when the speaker device 1 is viewed from the front, the direction of the current flowing through the first coil 112 (clockwise or counterclockwise) is the same as the direction of the current flowing through the second coil 212. The second bobbin 211 is supported by the frame 3 via the second damper unit 22 and can vibrate in the axial direction. The second coil 212 is connected to the same signal transmission circuit as the first coil 112, and a second driving force (second electromagnetic force) is generated in the axial direction by the action of an electric signal from the signal transmission circuit and the magnetic field of the second magnetic gap. The second driving force vibrates the second bobbin 211 together with the second coil 212, causing the second driving unit 20 to vibrate. At this time, a second excitation force is generated in the speaker device 1 in response to the vibration of the second driving unit. Here, because the radial magnetic flux direction of the second magnetic gap is opposite to the radial magnetic flux direction of the first magnetic gap, the second driving force is axially opposite to the first driving force at the same time. Therefore, the first excitation force and the second excitation force are also generated axially opposite to each other at the same time. Furthermore, to make the second excitation force equivalent to the first excitation force at the same time, adjustments can be made, such as by adding a weight to the second driving unit 20, increasing or decreasing the number of turns of the second coil 212, or adjusting the materials and sizes of the second voice coil 21 and the dampers 22a and 22b. Here, the second excitation force being equivalent to the first excitation force does not necessarily have to be strictly identical to the first excitation force, but may have a range large enough to achieve a cancellation effect. In this way, the second vibrational force is generated in the axially opposite direction to and equal to the first vibrational force, so that the first vibrational force is cancelled out and vibration of the speaker device 1 is suppressed.

[0050] The materials of each part of the first drive unit 10 and the second drive unit 20 are not particularly limited. For example, the diaphragm 12, the first damper unit 14, the dampers 22a and 22b, and the center cap 15 can be made of various materials, such as paper, resin, metal, or a composite or ceramic material that combines these. The edge portion 13 can be made of a relatively highly elastic polymer material, such as rubber or resin. Furthermore, a fiber material may also be used as the material of each part of the first drive unit 10 and the second drive unit 20. Furthermore, the base material of each part of the first drive unit 10 and the second drive unit 20 may be coated with a rubber coating or the like. The frame 3 and the spacer 23 can be made of a resin, paper, or metal material.

[0051] The diameters and thicknesses of the components shown in the drawings are merely examples, and the components are not limited to these shapes and dimensions.

[0052] In the speaker device 1, the minimum resonance frequency of the second drive unit 20 is set so that the minimum resonance frequency of the second drive unit 20 is the same as the minimum resonance frequency of the first drive unit 10 when the first drive unit 10 and the second drive unit 20 are housed inside the housing. The housing may be formed as part of a vehicle, and the form is not limited. The minimum resonance frequency of the second drive unit 20 is usually higher when the speaker device 1 is housed in a housing, so the minimum resonance frequency of the second drive unit 20 is set lower than the minimum resonance frequency of the first drive unit 10 when the speaker device 1 is in a standalone state. Here, "the minimum resonance frequency of the second drive unit 20 is the same as the minimum resonance frequency of the first drive unit 10" does not necessarily have to be exactly the same; it is sufficient that the minimum resonance frequency of the second drive unit 20 is within a certain range around the minimum resonance frequency of the first drive unit 10, for example, a range of ±20%. By having the minimum resonance frequency of the first drive unit 10 and the minimum resonance frequency of the second drive unit 20 be the same, resonance occurring in the housing can be more reliably prevented.

[0053] 4 is an explanatory diagram showing the amplitude of the damper of the speaker device according to the first embodiment of the present invention. Hereinafter, with reference to this drawing, details of the first damper section 14 and the positional relationship when the first damper section 14 and the second voice coil 21 are closest to each other will be described.

[0054] The shape of the first damper section 14 will be described. The first damper section 14 is composed of an inner peripheral section 141, a recessed section 142, an intermediate section 143, and an outer peripheral section 144. The inner peripheral section 141 is connected to the outer peripheral surface of the first bobbin 111, and the outer peripheral section 144 is connected to the frame 3. The recessed section 142 is disposed axially opposite the second voice coil 21, and has a large recessed shape when viewed axially forward from the second voice coil 21 side. The intermediate section 143 has a wave-shaped cross section, known as a corrugated shape.

[0055] When the first driving unit 10 and the second driving unit 20 are at the midpoint of their amplitudes (or when no electric signal is applied), the recessed portion 142 is located on an extension of the vibration direction of the second voice coil 21, farther away from the second voice coil 21 than an intermediate portion 143, which is another portion of the first damper portion 14. Specifically, as shown in Fig. 4, when a plane perpendicular to the axial direction including a position B1 indicating the front tip of the second voice coil 21 is used as a reference, a distance h1 to a plane perpendicular to the axial direction including the front tip of the recessed portion 142 is greater than a distance h2 to a plane perpendicular to the axial direction including the front tip of the intermediate portion 143.

[0056] Furthermore, the recessed portion 142 has higher rigidity than the intermediate portion 143, which is the other portion of the first damper portion 14. For example, the thickness can be increased and rigidity can be increased by forming a double structure in which a reinforcing member of the same shape is layered only on the recessed portion 142. The material of the reinforcing member may be the same as that of the recessed portion 142, or it may be a different material. This makes the recessed portion 142 less likely to deform than other portions such as the intermediate portion 143. Furthermore, the rigidity can be increased by adding a rib or the like to the recessed portion 142, or by forming the recessed portion 142 from a material that is more rigid than the intermediate portion 143.

[0057] Next, the positional relationship between the first damper section 14 and the second voice coil 21 when they are closest to each other will be described. When the first drive section 10 and the second drive section 20 are at the midpoint of their amplitudes, the connection point between the first damper section 14 and the first voice coil 11 is at position A1, and the front end of the second voice coil 21 is at position B1, as shown in FIG. 4. When an electric signal is applied to the first voice coil 11 and the second voice coil 21 and the first damper section 14 and the second voice coil 21 are closest to each other, the connection point between the first damper section 14 and the first voice coil 11 is at position A2, and the front end of the second voice coil 21 is at position B2. In other words, the front end, which is part of the second voice coil 21, is located within the recess 142 when the first damper section 14 and the second voice coil 21 are closest to each other. 4, the front end of the second voice coil 21 is not in contact with the recessed portion 142, and it can be seen that the first driving portion 10 and the second driving portion 20 do not interfere with each other. The recessed portion 142 is also designed so as not to interfere with the diaphragm 12.

[0058] In the speaker device 1 configured as described above, by making the diameter of the second voice coil 21 closer to that of the first voice coil 11, the magnetic circuit 30 that generates a magnetic field that vibrates the first drive unit 10 and the second drive unit 20 can be housed within the frame 3 while being laminated in the axial direction (vibration direction), improving assembly during manufacturing. Furthermore, by making the diameter of the second voice coil 21 closer to that of the first voice coil 11, the radial lengths of the first damper unit 14 and the second damper unit 22 become equal, and the second voice coil 21 can also ensure an amplitude amount equal to that of the first voice coil 11. In other words, the second drive unit 20 can generate a vibration damping force sufficient to offset the vibration (excitation force) transmitted from the first drive unit 10 to the entire speaker device 1 via the frame 3. This improves vibration damping characteristics while maintaining the quality of sound reproduction, especially bass reproduction.

[0059] Furthermore, by forming a repulsive magnetic circuit using the first magnet 32 ​​and the second magnet 34, the magnetic flux density of the first magnetic gap G1a and the second magnetic gap G2a is higher than when only the first magnet 32 ​​is used, improving the responsiveness to electrical signals of the first drive unit 10 and the second drive unit 20. Furthermore, the first bottom portion 33a of the first yoke 33, which is disposed between these two magnets, can be used as a path for both the magnetic flux passing through the first magnetic gap G1a and the magnetic flux passing through the second magnetic gap G2a, allowing the magnetic circuit 30 to be made thinner.

[0060] Furthermore, the first drive unit 10 and the second drive unit 20 are fixed to the frame 3 on their outer peripheries, but vibrate together with the first voice coil 11 and the second voice coil 21 on their inner peripheries, so that the amount of forward and backward movement increases toward the inside in the radial direction. In this case, the more the second voice coil 21, which vibrates forward and backward, is positioned on the outer periphery, the less likely the second voice coil 21 will interfere with the first damper unit 14 or the diaphragm 12 when the amplitude of the first voice coil 11 and the second voice coil 21 reaches its maximum. On the other hand, the closer the diameter of the second voice coil 21 is to the diameter of the first voice coil 11, i.e., the more inner the second voice coil 21 is positioned, the greater the possibility that the second voice coil 21 will interfere with the first damper unit 14 or the diaphragm 12 when the amplitude of the first voice coil 11 and the second voice coil 21 reaches its maximum. In contrast, by providing the recess 142 in the first damper section 14, even if the second voice coil 21 is positioned adjacent to the first voice coil 11, the second voice coil 21 does not interfere with the first damper section 14 or the diaphragm 12. Therefore, the second voice coil 21 can also maintain the same amplitude as the first voice coil 11, improving sound quality while being thinner. Furthermore, the recess 142 has increased rigidity and is less likely to deform, so the relative position of the second voice coil 21 does not shift, and contact with the second voice coil 21 can be reliably avoided. Furthermore, the first bottom 33a of the first yoke 33 can also be used as a plate for forming the second magnetic gap G2a, thereby enabling a thinner design and a lighter weight due to a reduced number of parts. Furthermore, by stacking the first magnet 32 ​​and the second magnet 34 radially inward of the second voice coil 21, the second magnet 34 can be minimized in size and weight.

[0061] As described above, the speaker device 1 of the first embodiment has good assembly properties during manufacturing, and can improve vibration damping characteristics while maintaining the quality of sound reproduction, especially bass sound reproduction. In addition, it is possible to achieve both improved vibration damping characteristics and a slim design.

[0062] (Second embodiment) In the speaker device 1 of the first embodiment described above, both the first magnet 32 ​​and the second magnet 34 were positioned radially inward from the second voice coil 21, but the speaker device 2 of the second embodiment differs in that the second magnet 134 is annular and therefore positioned radially outward from the second voice coil 21.

[0063] Fig. 5 is a perspective view of the speaker device 2 according to the second embodiment, and Fig. 6 is a side cross-sectional view in the XZ plane including the central axis O2 of the speaker device 2. The speaker device 2 according to the second embodiment will be described below with reference to these drawings. Note that the same components as those of the speaker device 1 according to the first embodiment are given the same reference numerals, and their description will be omitted.

[0064] The speaker device 2 of this embodiment is a cone-type speaker, and its main portion is symmetrical about the central axis O2 as shown in FIG. 6. In the following description, the direction parallel to the central axis O2 is defined as the axial direction, and the front-rear direction and the radial direction are defined as in the first embodiment. The speaker device 2 radiates sound forward from the first drive unit 10. The speaker device 2 is, for example, a woofer or subwoofer, and is capable of reproducing low frequencies with a large input.

[0065] The frame 103 has a cross-sectional concave shape whose diameter gradually decreases toward the rear, and a rear end portion of the frame 103 is connected to a second top plate 135 (described later) of the magnetic circuit 130. The magnetic circuit 130 includes a first top plate 131 (first magnetic member), a first magnet 132, a first yoke 133F and a second yoke 133R (intermediate magnetic members), a second magnet 134, and a second top plate 135 (second magnetic member). The first magnet 132 is disposed radially inward of the second voice coil 21, and the second magnet 134 is disposed radially outward of the second voice coil 21. Therefore, in the radial center portion of the speaker device 2, the components are stacked coaxially in the vibration direction of the first voice coil 11 and the second voice coil 21 in the order of the second yoke 133R disposed at the rearmost position, the first yoke 133F, the first magnet 132, and the first top plate 131. Furthermore, on the radially outer side of the speaker device 2, the components are stacked coaxially in the vibration direction of the first voice coil 11 and the second voice coil 21, starting from the rearmost second yoke 133R, followed by the second magnet 134 and the second top plate 135. By stacking the magnetic circuit 130 from the rear in this manner, assembly in the manufacturing process is facilitated. The first top plate 131, the first yoke 133F, the second yoke 133R, and the second top plate 135 are magnetic members. The first yoke 133F and the second yoke 133R are formed of, for example, the same material and are interconnected, thereby functioning as an integrated magnetic member (hereinafter referred to as the intermediate magnetic member 133). The radial size of the inner and outer diameters of the second magnet 134 is greater than the radial size of the outer diameter of the first magnet 132. This increases the magnetic flux density in the second magnetic gap G12a that acts on the second voice coil 21, which has a larger diameter and is heavier than the first voice coil 11. The first magnet 132 and the second magnet 134 may have a different size relationship than in the embodiment. In particular, in the second embodiment, there is more space in the radial direction than in the first embodiment, making it easier to make the second magnet 134 larger. Therefore, it is possible to use a lower-cost magnet that has a smaller magnetic force relative to its size than in the first embodiment.

[0066] The second yoke 133R has a disk-shaped second bottom portion 133Ra coaxial with the central axis O2 and a cylindrical second protrusion 133Rc protruding forward from the center of the second bottom portion 133Ra. In this embodiment, as shown in FIG. 6, the second yoke 133R has a recess in the bottom surface (rear surface) of the second bottom portion 133Ra to reduce weight and facilitate centering during processing. The second magnet 134 is coaxial with the central axis O2 and has an annular disk shape with an inner diameter larger than the outer diameter of the second protrusion 133Rc and an outer diameter slightly larger than the outer diameter of the second bottom portion 133Ra. The second top plate 135 has an annular disk shape with an inner diameter larger than the outer diameter of the first yoke 133F and an outer diameter slightly smaller than the outer diameter of the second magnet 134. The second top plate 135 is stacked on the top surface (front surface) of the second magnet 134.

[0067] The first yoke 133F has a disk-shaped first bottom portion 133Fa coaxial with the central axis O2, a first cylindrical portion 133Fb standing from the periphery of the first bottom portion 133Fa, and a cylindrical first protrusion portion 133Fc protruding forward from the center of the first bottom portion 133Fa. The first yoke 133F is stacked on the top surface (front surface) of the second protrusion portion 133Rc. The first magnet 132 is cylindrical, coaxial with the central axis O2, and has approximately the same diameter as the first protrusion portion 133Fc, and is stacked on the top surface (front surface) of the first protrusion portion 133Fc. The first top plate 131 is cylindrical, slightly larger in diameter than the first magnet 132, and is stacked on the top surface (front surface) of the first magnet 132.

[0068] The second top plate 135 has an axial length (thickness) that is approximately the same as the axial length (thickness) of the first bottom portion 133Fa, and is disposed adjacent to the radially outer side of the first bottom portion 133Fa. The first bottom portion 133Fa has a protrusion 133Fd that protrudes radially outward from the outer circumferential surface of the first cylindrical portion 133Fb, i.e., toward the second top plate 135. An attachment flange is formed on the outer periphery of the front end of the second top plate 135, and the attachment flange is connected to the rear end of the frame 103.

[0069] The first cylindrical portion 133Fb extends to the top surface (front surface) of the first top plate 131. The outer diameters of the first top plate 131, the first magnet 132, and the first protrusion 133Fc are each smaller than the inner diameter of the first cylindrical portion 133Fb. Therefore, as shown in FIG. 6, an annular first gap G11 is formed radially inside the first cylindrical portion 133Fb between the inner peripheral surface of the first cylindrical portion 133Fb and the outer peripheral surfaces of the first top plate 131, the first magnet 132, and the first protrusion 133Fc. The annular first gap G11 extends from the front end of the first cylindrical portion 133Fb to the top surface (front surface) of the first bottom portion 133Fa. A magnetic field that is substantially uniform in the circumferential direction is generated in a first magnetic gap G11a formed by the outer peripheral surface of the first top plate 131 and the inner peripheral surface of the first cylindrical portion 133Fb in the first gap G11.

[0070] The outer diameters of the first bottom 133Fa and the second protrusion 133Rc are smaller than the inner diameters of the second magnet 134 and the second top plate 135. Therefore, as shown in FIG. 6, an annular second gap G12 is formed between the first bottom 133Fa, the second protrusion 133Rc, the second bottom 133Ra, the second magnet 134, and the second top plate 135, and the annular second gap G12 extends from the front end of the second top plate 135 to the top surface (front surface) of the second bottom 133Ra. A substantially uniform magnetic field is generated in the circumferential direction in the second gap G12, in a second magnetic gap G12a formed by the outer peripheral surface of the first bottom 133Fa and the inner peripheral surface of the second top plate 135. In this embodiment, the distance of the second magnetic gap G12a is narrowed by adjusting the protrusion amount of the protrusion 133Fd of the first bottom 133Fa. This allows the magnetic flux passing through the second magnetic gap G12a to be increased, and the leakage magnetic flux to be reduced.

[0071] 7 is an explanatory diagram showing the arrangement of the magnetized surfaces of magnets and the direction of the magnetic field of the magnetic circuit according to the second embodiment of the present invention. Specifically, it is an explanatory diagram showing the magnetic polarity arrangement of the magnetized surfaces of the first magnet 132 and the second magnet 134 in the laminated structure of the magnetic circuit 130, and the direction of the magnetic field of the magnetic circuit 130 generated by this arrangement.

[0072] The first magnet 132 and the second magnet 134 are, for example, permanent magnets, and are magnetized in the axial direction. That is, if the disc surface on one side of the first magnet 132 and the second magnet 134 is an S pole, the disc surface on the other side is an N pole. As shown in Fig. 7, in the magnetic circuit 130, when stacked, one magnetized surface of the first magnet 132 (the front magnetized surface, N pole) is connected to the bottom surface (rear surface) of the first top plate 131, and the other magnetized surface of the first magnet 132 (the rear magnetized surface, S pole) is connected to the first convex portion 133Fc of the first yoke 133F, i.e., the top surface (front surface) of the intermediate magnetic member. One magnetized surface (rear magnetized surface, S pole) of the second magnet 134 is connected to the outer peripheral top surface (front surface) of the second bottom portion 133Ra of the second yoke 133R, which is a surface different from the surface to which the first magnet 132 of the intermediate magnetic member is connected, and the other magnetized surface (front magnetized surface, N pole) of the second magnet 134 is connected to the bottom surface (rear surface) of the second top plate 135. As described above, in the speaker device 2 of the second embodiment, the magnetic circuit 130 forms a repulsive magnetic circuit in which the first magnet 132 and the second magnet 134 are arranged so that like poles (S poles in FIG. 7 ) face each other in the magnetic circuit via three layers of magnetic members (the intermediate magnetic member consisting of the first top plate 131, the first yoke 133F, and the second yoke 133R, and the second top plate 135). Note that the magnetic polarities of the first magnet 132 and the second magnet 134 may be reversed, so that the N poles face each other. Furthermore, the first magnet 132 and the second magnet 134 may be arranged with the same poles facing each other, or with opposite poles facing each other, and the magnetization direction is not limited. For example, the magnetization directions of the first magnet 132 and the second magnet 134 may be reversed, with the south pole facing the north pole. This is true whether an internal magnet type or an external magnet type is used for the magnetic circuit.

[0073] 7, two flows of magnetic flux are generated in the magnetic circuit 130 of the speaker device 2: a flow of magnetic flux (arrow C) from the first top plate 131 through the first magnetic gap G11a toward the first cylindrical portion 133Fb and first bottom portion 133Fa of the first yoke 133F, and a flow of magnetic flux (arrow D) from the second top plate 135 through the second magnetic gap G12a toward the first bottom portion 133Fa, the second convex portion 133Rc, and the second bottom portion 133Ra. In particular, in the portion where the two arrows C and D overlap, the magnetic field directions are aligned, and therefore, by using two magnets (the first magnet 132 and the second magnet 134), the magnetic fields generated in the first magnetic gap G11a and the second magnetic gap G12a may be reinforced. In this case, the direction of the magnetic flux flow in the first magnetic gap G11a and the direction of the magnetic flux flow in the second magnetic gap G12a are opposite to each other with respect to the radial direction, as in the first embodiment.

[0074] In the speaker device 2 configured as described above, by making the diameter of the second voice coil 21 closer to that of the first voice coil 11, the magnetic circuit 130 constituting the first drive unit 10 and the second drive unit 20 is housed within the frame 103 while being laminated in the axial direction (vibration direction), thereby improving assembly during manufacturing. Furthermore, by making the diameter of the second voice coil 21 closer to that of the first voice coil 11, the radial lengths of the first damper unit 14 and the second damper unit 22 become equal, and the second voice coil 21 can also ensure an amplitude amount equal to that of the first voice coil 11. That is, the second drive unit 20 can generate a vibration damping force sufficient to offset the vibration (excitation force) transmitted from the first drive unit 10 to the entire speaker device 2 via the frame 103. This improves vibration damping characteristics while maintaining the quality of sound reproduction, particularly bass reproduction.

[0075] Furthermore, by forming a repulsive magnetic circuit using the first magnet 132 and the second magnet 134, the magnetic flux density in the first magnetic gap G11a and the second magnetic gap G12a is higher than when only the first magnet 132 is used, improving the responsiveness of the first drive unit 10 and the second drive unit 20 to electrical signals. Furthermore, the first bottom portion 133Fa, which is located between these two magnets, can serve as a path for both the magnetic flux passing through the first magnetic gap G11a and the magnetic flux passing through the second magnetic gap G12a. This allows the first voice coil 11 to be located more centrally, ensuring sufficient amplitude, while also allowing the diameter of the second voice coil 21 to be closer to the diameter of the first voice coil 11. At the same time, the number of components in the magnetic circuit 130 can be reduced and the magnetic circuit 130 can be made thinner.

[0076] Furthermore, the first drive unit 10 and the second drive unit 20 are fixed to the frame 103 on their outer peripheries, but vibrate together with the first voice coil 11 and the second voice coil 21 on their inner peripheries, and therefore the amount of forward and backward movement increases toward the center. In this case, the more the second voice coil 21, which vibrates forward and backward, is positioned on the outer periphery, the less likely the second voice coil 21 will interfere with the first damper unit 14 or the diaphragm 12 when the amplitude of the first voice coil 11 and the second voice coil 21 reaches its maximum. On the other hand, the closer the diameter of the second voice coil 21 is to the diameter of the first voice coil 11, i.e., the more inner the second voice coil 21 is positioned, the greater the possibility that the second voice coil 21 will interfere with the first damper unit 14 or the diaphragm 12 when the amplitude of the first voice coil 11 and the second voice coil 21 reaches its maximum. In contrast, by providing the first damper portion 14 with the recessed portion 142, even if the second voice coil 21 is disposed adjacent to the first voice coil 11, the second voice coil 21 does not interfere with the first damper portion 14 or the diaphragm 12. Therefore, the second voice coil 21 can also be made thinner while ensuring an amplitude equivalent to that of the first voice coil 11 and improving sound quality. Furthermore, the recessed portion 142 has increased rigidity and is less likely to deform, so that the relative position with the second voice coil 21 does not shift and contact with the second voice coil 21 can be reliably avoided. Furthermore, because the first bottom portion 133Fa can also be used as a plate for forming the second magnetic gap G12a, the device can be made thinner and lighter due to a reduced number of parts.

[0077] 7, the magnetization direction in the axial direction is the same when the first magnet 132 and the second magnet 134 are arranged. Therefore, after the magnetic circuit 130 is assembled in the manufacturing process, the magnetization process of the first magnet 132 and the second magnet 134 can be performed simultaneously.

[0078] As described above, the speaker device 2 of the second embodiment can be easily assembled during manufacturing, and can improve vibration-damping characteristics while maintaining the quality of audio reproduction. Furthermore, it is possible to achieve both improved vibration-damping characteristics and a thinner design.

[0079] Although the first and second embodiments of the present invention have been described above, the aspects of the present invention are not limited to these embodiments.

[0080] For example, the location where the speaker device is installed is not limited to a vehicle.

[0081] In the above embodiment, the first damper section 14 and the second damper section 22 have a corrugated cross-sectional shape, but other shapes are also possible. For example, they may be leaf springs or have a single arc shape instead of a corrugated shape. In the above embodiment, the dampers 22a and 22b of the second damper section 22 are identical when mounted, but they may have shapes that are inverted in the axial direction when mounted. This improves the movement symmetry and linearity of the second voice coil 21 during forward and backward vibration, thereby equalizing the stress applied to each damper 22a and 22b and improving the support strength of the second voice coil 21. Furthermore, improving the linearity of the second voice coil 21 allows the second magnetic gap G12a to be narrower, thereby strengthening the magnetic field.

[0082] In the above embodiment, the second damper section 22 is composed of two dampers 22a and 22b. However, it may be composed of a single damper. It may also be composed of three or more dampers. By using multiple dampers, stress is applied to each damper equally, improving the symmetry and linearity of the movement of the second voice coil 21 during forward and backward vibration, and improving the support strength of the second voice coil 21. Furthermore, improving the linearity of the second voice coil 21 allows the spacing of the second magnetic gap G12a to be narrowed, thereby strengthening the magnetic field. Furthermore, when multiple dampers are used, the above embodiment uses the spacer 23 to indirectly fix the dampers to the frame 3, 103 while maintaining axial spacing between them. However, the outer peripheries of the multiple dampers may be directly connected and fixed to the frame 3, 103 with an adhesive or the like.

[0083] Furthermore, in the above embodiment, the first coil 112 and the second coil 212 are connected to the same signal circuit and the same electrical signal is input thereto, but the second coil 212 may be connected to a different signal circuit and receive an electrical signal different from that input to the first coil 112. For example, a first electrical signal that generates a first driving force that vibrates the first voice coil 11 may be input to the first coil 112, and a second electrical signal that generates a second driving force that vibrates the second voice coil 21 may be input to the second coil 212, whereby the second electrical signal generates a second driving force equivalent to a second excitation force that cancels out the first excitation force. This allows for fine adjustment of the degree of cancellation. In the above embodiment, the first coil 112 and the second coil 212 are wound in the same direction. However, the first coil 112 and the second coil 212 may be wound so that the direction of the force generated in the first coil 112 by the magnetic flux crossing the first coil 112 and the current flowing through the first coil 112 is opposite to the direction of the force generated in the second coil 212 by the magnetic flux crossing the second coil 212 and the current flowing through the second coil 212. In other words, the second coil 212 may be wound so that the first excitation force can be suppressed by the second excitation force. Furthermore, when the second coil 212 is connected to a signal circuit separate from the first coil 112, the separate signal circuit may output an electric signal in which a third electric signal that generates a third driving force equivalent to a third excitation force that suppresses vibrations generated outside the speaker devices 1 and 2 is superimposed on the second electric signal. This makes it possible to cancel out vibrations generated outside the speaker devices 1 and 2.

[0084] In the first embodiment, the intermediate magnetic member is composed of one component (first yoke 33), and in the second embodiment, the intermediate magnetic member is composed of two components (first yoke 133F and second yoke 133R), but the intermediate magnetic member may be composed of multiple components including other magnetic component parts. Similarly, the first magnetic member and the second magnetic member may also be composed of multiple magnetic component parts.

[0085] Furthermore, in the first and second embodiments, the first voice coil 11 and the second voice coil 21 each have a cylindrical shape with a circular cross section, but the cross section may be, for example, a polygonal or elliptical shape. [Explanation of symbols]

[0086] 1, 2: Speaker device 3, 103: Frame 10: First drive unit 11: 1st voice coil 12: Vibration plate 14: First damper section 20: Second drive unit 21: Second voice coil 22: Second damper section 30, 130: Magnetic circuit 31, 131: Top plate 32, 132: First magnet 33, 133F: 1st York 33d, 133Fd:Protrusion 34, 134: Second magnet 35, 133R: Second yoke 135: Second top plate 142: Recessed part G1a, G11a: First magnetic gap G2a, G12a: Second magnetic gap

Claims

1. A first voice coil; a second voice coil disposed radially outward of the first voice coil; a first damper that supports the first voice coil on a frame; a second damper that supports the second voice coil on the frame; a magnetic circuit having a first magnet and a second magnet; Equipped with the first magnet and the second magnet are arranged side by side in a vibration direction of the first voice coil, the first magnet and the second magnet are disposed radially inside the second voice coil, the magnetic circuit includes a first magnetic member, an intermediate magnetic member, and a second magnetic member; the intermediate magnetic member has a bottomed cylindrical shape including a plate-shaped first bottom portion and a first cylindrical portion extending from a peripheral edge of the first bottom portion; the first magnet is laminated on the intermediate magnetic member; the first magnetic member is laminated on the first magnet, a first magnetic gap in which the first voice coil is disposed is formed between the first magnetic member and the first cylindrical portion; the second magnetic member has a bottomed cylindrical shape including a plate-shaped second bottom portion and a second cylindrical portion standing upright from the periphery of the second bottom portion, the second magnet is laminated on the second magnetic member; the first bottom portion is stacked on the second magnet; the second cylindrical portion extends to the intermediate magnetic member, and a second magnetic gap is formed between the second cylindrical portion and the intermediate magnetic member, in which the second voice coil is disposed; The second magnetic gap is formed between the first bottom portion and the second cylindrical portion. Speaker device.

2. the intermediate magnetic member has a protrusion that protrudes radially outward beyond the outer circumferential surface of the first cylindrical portion and forms the second magnetic gap; 2. The speaker device according to claim 1.

3. The radial size of the second magnet is larger than the radial size of the first magnet.

3. The speaker device according to claim 1 or 2.

Images