Electroacoustic transducer and earphone

Abstract

Provided is an electro-acoustic transducer capable of maintaining stable performance. An electro-acoustic transducer (1) for transmitting vibrations to a bone is provided with: a main frame (10) having at least a cylindrical section; a vibration unit (30) that is disposed on the inside of the main frame and vibrates in the axial direction of the main frame in accordance with an input signal; and an elastic member (20) that is connected to at least the vibrating part and is formed from an organic material or a polymer material.

Description

TECHNICAL FIELD

[0001] The present application relates to an electro-acoustic transducer that performs bone conduction, and a headphone. BACKGROUND

[0002] A sound output device is known that brings an outer wall surface into contact with a skull and a bone around an entrance of an external auditory meatus, thereby hearing air conduction sound that is generated in the external auditory meatus via bone conduction from the skull or the like.

[0003] Hitherto, for example, a bone conduction vibration source device for a mobile phone or the like is known that performs acoustic processing on a sound signal for bone conduction vibration, and outputs the processed signal as a driving signal to a bone conduction vibration source (for example, refer to Patent Literature 1). Also disclosed is a stereo headphone that has a bone conduction portion, and a branch portion that is connected at one end to the bone conduction portion to become a vibration source (for example, refer to Patent Literature 2).

[0004] A sound output device that utilizes bone conduction has a vibration portion that vibrates according to a sound signal. There is concern that confusion will occur at a resonance point in the vibration portion, that is, vibration in a non-intended direction will occur, and a noise will be generated as a result.

[0005] PRIOR ART DOCUMENTS

[0006] PATENT LITERATURE

[0007] Patent Literature 1: Japanese Patent Application Publication No. 2013-197730

[0008] Patent Literature 2: Japanese Patent Application Publication No. 2014-116755 SUMMARY

[0009] An object of the present application is to provide an electro-acoustic transducer and a headphone that can maintain stable performance.

[0010] The electro-acoustic transducer of the present application is a vibration-to-bone transmission electro-acoustic transducer that includes: a main frame that has at least a cylindrical portion; a vibration portion that is disposed inside the main frame, and vibrates in an axial direction of the main frame according to an input signal; and an elastic member that is connected to at least the vibration portion, and is formed of an organic substance or a high molecular material.

[0011] Further, the headphone of another aspect of the present application includes: a headband; and a pair of the above-described electro-acoustic transducers that are respectively held at both ends of the headband.

[0012] EFFECT OF THE INVENTION

[0013] According to the present application, an electro-acoustic transducer and a headphone that can maintain stable performance can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a schematic perspective view showing an embodiment of the headphone of the present application.

[0015] Figure 2 is a first embodiment of the electro-acoustic transducer of the present application, (a) is a perspective view as viewed from the front side, and (b) is an exploded perspective view of the electro-acoustic transducer.

[0016] Figure 3 is a longitudinal sectional view of the electro-acoustic transducer.

[0017] Figure 4 is a second embodiment of the electro-acoustic transducer of the present application, (a) is a perspective view as viewed from the front side, and (b) is an exploded perspective view of the electro-acoustic transducer.

[0018] Figure 5 is a longitudinal sectional view of the electro-acoustic transducer.

[0019] Figure 6 is a third embodiment of the electro-acoustic transducer of the present application, (a) is a perspective view as viewed from the front side, and (b) is an exploded perspective view of the electro-acoustic transducer.

[0020] Figure 7 is a longitudinal sectional view of the electro-acoustic transducer.

[0021] Figure 8 is a fourth embodiment of the electro-acoustic transducer of the present application, (a) is a perspective view as viewed from the front side, and (b) is an exploded perspective view of the electro-acoustic transducer.

[0022] Figure 9 is a longitudinal sectional view of the electro-acoustic transducer.

[0023] Figure 10 is a fifth embodiment of the electro-acoustic transducer of the present application, (a) is a perspective view as viewed from the front side, and (b) is an exploded perspective view of the electro-acoustic transducer.

[0024] Figure 11 shows the electro-acoustic transducer, (a) is a longitudinal sectional view, and (b) is a transverse sectional view.

[0025] Figure 12 is a sixth embodiment of the electro-acoustic transducer of the present application, (a) is a perspective view as viewed from the front side, and (b) is an exploded perspective view of the electro-acoustic transducer.

[0026] Figure 13 shows the electro-acoustic transducer, (a) is a longitudinal sectional view, and (b) is a transverse sectional view.

[0027] Figure 14Fig. 7 is a perspective view of an electro-acoustic transducer according to a seventh embodiment of the present application, (a) is a perspective view as viewed from the front side, and (b) is an exploded perspective view of the electro-acoustic transducer.

[0028] Figure 15 Fig. 8 is a longitudinal sectional view of an electro-acoustic transducer according to an eighth embodiment of the present application.

[0029] Figure 16 Fig. 9 is a longitudinal sectional view of an electro-acoustic transducer according to a ninth embodiment of the present application.

[0030] Figure 17 Fig. 10 is a graph showing the frequency characteristics of the electro-acoustic transducer according to the present application and an electro-acoustic transducer according to a related art.

[0031] Figure 18 Fig. 11 is a longitudinal sectional view of a first example of an electro-acoustic transducer according to a related art.

[0032] Figure 19 Fig. 12 is a longitudinal sectional view of a second example of an electro-acoustic transducer according to a related art.

[0033] Figure 20 Fig. 13 is a longitudinal sectional view of a third example of an electro-acoustic transducer according to a related art. DETAILED DESCRIPTION

[0034] Hereinafter, embodiments of an electro-acoustic transducer according to the present application will be described with reference to the accompanying drawings. In the following description, the axial direction of the electro-acoustic transducer 1 will be referred to as the Y direction, and the directions orthogonal to the Y direction will be referred to as the X direction and the Z direction. In addition, the surface facing the +Y direction will be referred to as the upper surface, and the surface facing the -Y direction will be referred to as the bottom surface. Furthermore, the surface facing the -X direction will be referred to as the front surface, and the surface facing the +X direction will be referred to as the back surface.

[0035] • Headphone •

[0036] As shown in Fig. 1, the headphone 1000 mainly includes a pair of electro-acoustic transducers 1, a pair of housings 2, and a headband 3. The pair of housings 2 are each a substantially rectangular parallelepiped, and the electro-acoustic transducer 1 is built in the inside thereof. The headband 3 is a substantially U-shaped member. The both end portions of the headband 3 are bent in directions substantially orthogonal to the U-shaped portion, and hang on the ears of the wearer in the wearing state. The housings 2 are respectively attached to the both end portions of the headband 3. That is, the electro-acoustic transducers 1 are held to the both end portions of the headband 3 via the housings 2. The headband 3 sandwiches the head of the wearer in the wearing state, and the housings 2 are pressed to the vicinity of the ears by the elastic force of the headband 3. Figure 1

[0037] ​In addition, in this embodiment, the electroacoustic transducer is described as mainly transmitting vibrations to the ear cartilage. The technical scope of the present invention is not limited to this, and includes headphones and electroacoustic transducers that transmit vibrations to any bones other than the ear cartilage, including cartilage and hard bones such as the skull.

[0038] ●Electroacoustic converter (1)●

[0039] First, a first embodiment of the electroacoustic transducer of this embodiment will be described. The electroacoustic transducer 1 is, for example, an earphone unit.

[0040] like Figure 2 (a) and Figure 2 As shown in FIG. 1( b ), the electroacoustic transducer 1 is a substantially cylindrical component that is worn in pairs on the left and right ears. The electroacoustic transducer 1 mainly includes a main frame 10 , an elastic member 20 , a vibrating portion 30 , a coil 40 , and a unit base 50 .

[0041] The main frame 10 is a member having a cylindrical portion that defines the outer wall of the electroacoustic converter 1. The main frame 10 is substantially cylindrical in the present embodiment, but may also be in an appropriate configuration such as an elliptical cylindrical shape or a prismatic cylindrical shape.

[0042] The elastic member 20 is a cylindrical member disposed inside the main frame 10. In this embodiment, the elastic member 20 is disposed along the entire circumference of the vibrating portion 30. The elastic member 20 is a member formed of an organic or polymeric material that exhibits elastic force. For example, the elastic member 20 is a member that exerts elastic force through a porous structure, more specifically, a polyurethane foam material. Alternatively, the elastic member 20 may be formed of a suitable sponge material. Furthermore, the elastic member 20 may be formed of an elastomer such as rubber or a gel material.

[0043] The elastic member 20 holds the vibrating portion 30 to the main frame 10. The elastic member 20 is connected to the outer peripheral surface of the vibrating portion 30 along the vibration direction and the inner peripheral surface of the main frame 10. For example, the elastic member 20 is bonded to the outer peripheral surface of the vibrating portion 30 and the inner peripheral surface of the main frame 10 using a suitable adhesive material. As a result, the elastic member 20 controls the vibration of the vibrating portion 30.

[0044] The vibrating portion 30 is a component disposed inside the through-hole 13 of the main frame 10. The vibrating portion 30 vibrates in the axial direction of the through-hole 13 in response to a signal.

[0045] like Figure 2 As shown in FIG. 2( b ), the vibrating portion 30 mainly includes a cover-shaped yoke 31 , a magnet 32 ​​, and a center yoke 33 .

[0046] The cover-shaped yoke 31 is a bottomed cylindrical member that constitutes the upper surface and the side surface of the vibration section 30. The end portion of the upper surface side (+Y side) of the cover-shaped yoke 31 is exposed on the upper surface (+Y side) of the electro-acoustic transducer 1. As shown in FIG. 1, the lower end of the -Y side of the cover-shaped yoke 31 opposes the unit base 50 with a gap. The inner diameter of the cover-shaped yoke 31 is larger than the outer diameter of the coil 40. As a result, the cover-shaped yoke 31 covers a portion of the outer periphery of the coil 40. The elastic member 20 is joined to the outer peripheral surface of the cover-shaped yoke 31. Figure 3

[0047] The magnet 32 is a substantially cylindrical magnet that is disposed inside the cover-shaped yoke 31. The magnet 32 can also be joined to the inner bottom surface of the cover-shaped yoke 31. In addition, the center yoke 33 is a disc-shaped member that is joined to the lower end of the magnet 32. The outer diameter of the magnet 32 is smaller than the inner diameter of the hole 40a of the coil 40. As a result, the magnet 32 and the center yoke 33 are able to move in the axial direction (y direction) inside the hole 40a. A Lorentz force is generated between the magnet 32 and the coil 40. As a result, the vibration section 30 vibrates in the axial direction.

[0048] The coil 40 is a circular ring-shaped member that is held to the unit base 50. The magnet 32 and the center yoke 33 are inserted into the hole 40a formed in the central portion of the coil 40.

[0049] As described thus far, the vibration direction in which the vibration section 30 vibrates in accordance with the signal is the Y direction, which is different from the vertical direction in the wearing state. That is, the vibration section 30 bears the gravitational force in a direction different from the vibration direction. The elastic member 20 supports the vibration section 30 by being joined to the main frame 10 and the vibration section 30. That is, according to the elastic member 20, sagging of the vibration section 30 based on the gravitational force is prevented.

[0050] The elastic member 20 has a prescribed hardness and a recovery coefficient. As a result, the elastic member 20 alleviates and eliminates abnormal vibration at the resonance point of the vibration section 30, and suppresses displacement of the vibration section 30 in a direction different from the vibration direction. In addition, the elastic member 20 is joined along the circumferential direction of the vibration section 30, thereby suppressing displacement of the vibration section 30 in the rotational direction. Displacement of the vibration section 30 in a direction other than the vibration direction in which the vibration section 30 vibrates in accordance with the signal becomes a cause of abnormal sound. In relation to this, the elastic member 20 suppresses abnormal sound by preventing displacement other than the axial direction, and furthermore, it is possible to improve the sound quality of the electro-acoustic transducer 1. The characteristics of the elastic member 20, such as the hardness or the recovery coefficient, are appropriately adjusted in accordance with the desired sound quality, the mass or the shape of the vibration section 30, and the like.

[0051] Here, a Figure 19 An electro-acoustic transducer 1a related to the technology will be described.

[0052] Figure 19 ​The illustrated electro-acoustic transducer la mainly includes a cylindrical main frame 10a, a circular plate-shaped suspension 20a, and a vibrating section 30a that vibrates inside the main frame 10a.

[0053] The suspension 20a abuts against the inside of the protrusion 15a formed in the inner wall of the main frame 10a. In addition, the central portion of the vibrating section 30a is connected to the center of the suspension 20a by a connecting member such as a screw. As a result, the vibrating section 30a is supported by the suspension 20a to the protrusion 15a. Therefore, the vibration fulcrum of the vibrating section 30a is the connecting member, and the abutting portion of the suspension 20a to the protrusion 15a becomes the action point. In this way, the electro-acoustic transducer la in which the center of gravity and the vibration fulcrum of the vibrating section 30a are separated has a risk of causing confusion at the resonance point, that is, causing vibration in a non-intended direction. The confusion at the resonance point becomes a cause of abnormal noise.

[0054] In addition, Figure 19 In the wearing state, the vertical direction is the direction of the paper surface. The vibration direction of the vibrating section 30a in the wearing state is different from the vertical direction. Therefore, for the vibrating section 30a, a gravitational force is applied in a direction different from the vibration direction. The first end side of the vibrating section 30a is connected to the suspension 20a at the substantially central portion, and on the other hand, the second end side is not supported, and becomes a cantilever beam state. Therefore, the second end of the vibrating section 30a sags in the direction of the gravitational force. As a result, the electro-acoustic transducer la generates an unnecessary moment or torque at the resonance. The moment or torque becomes a cause of confusion or breakage.

[0055] Furthermore, in the electro-acoustic transducer la that transmits vibration to the ear cartilage, since the ear cartilage is vibrated, the mass of the vibrating section 30a is larger than that of the earphone unit that vibrates a diaphragm. Therefore, the sag of the vibrating section 30a and the confusion at the resonance point become larger than those of the earphone unit having the diaphragm. As a result, the sag and the confusion become a cause of failure.

[0056] Still further, the vibrating section 30a of the electro-acoustic transducer la sometimes vibrates according to vibration from the outside. In this case, due to the vibration of the vibrating section 30a, an electromotive force is generated in the coil 140 disposed opposite to the vibrating section 30a. As a result, for the earphone unit having the vibrating section, there is a concern that the vibration becomes abnormal noise and is mixed into sound.

[0057] In addition, Figure 20 The electro-acoustic transducer 2b of the related art illustrated mainly includes a cylindrical main frame 10b, a vibrating section 30b that vibrates inside the main frame 10b, a circular plate-shaped suspension 20b that holds the vibrating section 30b at the first end side of the main frame 10b, and a flat plate-shaped damper 60b that holds the vibrating section 30b at the second end side of the main frame 10b. The suspension 20b is constituted by, for example, a plate spring made of metal.

[0058] The vibration section 30b is held at the first and second ends of the main frame 10b via the damper 60b. Therefore, the electro-acoustic transducer lb suppresses unintended vibration of the vibration section 30b, and thus failure is less likely to occur. In addition, between the vibration section 30b and the main frame 10b, the elastic member 20 having an elastic force and the damper 60b are respectively interposed, and thus the amplitude at the resonance point (Q value) is effectively controlled. As a result, even if configured to use the cartilage conduction with the mass of the vibration section 30b being larger than that of the earphone unit having a diaphragm, the electro-acoustic transducer lb can be implemented to be high in sound quality while suppressing unintended vibration.

[0059] On the other hand, the suspension 20b of the electro-acoustic transducer 2b of the related art is a metal plate spring, and thus there is a concern of plastic deformation. In addition, the influence of resonance is sometimes large, and the price is expensive.

[0060] In this regard, the electro-acoustic transducer 1 of the present application has the elastic member 20 formed of an organic substance or a polymer material having a prescribed or greater elastic force, instead of the elastic member exerting an elastic force by a configuration of metal and resin. Therefore, according to the electro-acoustic transducer 1 of the present application, the concern of plastic deformation of the elastic member 20 is alleviated. In addition, the influence of resonance can be alleviated, and on this basis, the configuration can be inexpensive.

[0061] • Frequency response characteristics

[0062] Figure 18 The frequency characteristics of the earphone unit are shown. That is, the horizontal axis shows the frequency, and the vertical axis shows the output level (dBV). The dashed line shows the frequency characteristics of the electro-acoustic transducer la of the related art, the single-dot chain line shows the frequency characteristics of the electro-acoustic transducer lb of the related art, and the solid line shows the frequency characteristics of the electro-acoustic transducer 1 of the present application.

[0063] The electro-acoustic transducer la of the related art has a resonance point F0. The frequency of the resonance point F0 is determined by the relationship between the spring constant of the suspension 20a and the weight of the vibration section 30a. As a result, the electro-acoustic transducer la has a concern of giving an unpleasant feeling to the head of the wearer due to very large vibration generated by the frequency of the resonance point F0.

[0064] With respect to the frequency characteristics of the electro-acoustic transducer lb of the related art, the resonance in the low range is alleviated by the damper 60b, and is smoother than the frequency characteristics of the electro-acoustic transducer la. That is, the electro-acoustic transducer lb can suppress unintended resonance, and alleviate the unpleasant feeling given to the head.

[0065] The frequency characteristic of the electro-acoustic transducer 1 of the present application is the same as that of the electro-acoustic transducer lb of the related art, and the peak is lowered and smoothed. In addition, the frequency of the peak is higher than the resonance point F0 of the electro-acoustic transducer la. Therefore, it can be said that the damping based on the elastic member 20 sufficiently functions. In addition, it is known that the sensitivity in the frequency characteristic of the electro-acoustic transducer 1 of the present application is also sufficiently high, and the sound pressure of the electro-acoustic transducer la or more can be achieved in a wide band.

[0066] • Electro-acoustic transducer (2)

[0067] In the present embodiment, the electro-acoustic transducer is different from the electro-acoustic transducer of the present embodiment, and the description is made focusing on the part different from the above-described mode. In addition, the same reference numerals are attached to the same configuration as that of the first embodiment. In addition, the electro-acoustic transducer described below is the same configuration as that of the electro-acoustic transducer 1 unless otherwise specified.

[0068] Figure 4 and Figure 5 The electro-acoustic transducer 101 of the second embodiment shown in FIG. 12 is different from the first embodiment in that the main frame 110 and the elastic member 120 are a bottomed cylinder in which the cylindrical portions 111 and 121 are joined to the bottom portions 112 and 122, respectively. The surface of the vibration portion 30 facing the vibration direction, that is, the outer wall surface 31a of the cover-shaped yoke 31 is opposed to the bottom portion 112 of the main frame 110 with the elastic member 120 interposed therebetween. In addition, the cylindrical portion 121 of the elastic member 120 is joined to the cylindrical portion 111 of the main frame 110, and the bottom portion 122 of the elastic member 120 is joined to the bottom portion 112 of the main frame 110. According to this configuration, the positioning in the axial direction (Y direction) is easy, and thus the productivity is high. In addition, the vibration portion 30 is not exposed, and thus the risk of breakage can be reduced. In addition, an appropriate opening can be formed in the elastic member 120. In addition, a slit can be formed in the elastic member 120. According to this configuration, the flexibility of the elastic member 120 can be improved.

[0069] • Electro-acoustic transducer (3)

[0070] Figure 6 and Figure 7The electro-acoustic transducer 201 of the third embodiment shown has a suspension 260 in the electro-acoustic transducer 101 of the second embodiment. The suspension 260 is a member having a protrusion 262 in the center of a substantially circular disc portion 261. In addition, a plurality of holes are formed in the disc portion 261, becoming springs that exert an elastic force in the Y direction. In addition, the radial end portion of the disc portion 261 is latched to one end of the main frame 10. In the vibrating portion 230 possessed by the electro-acoustic transducer 201, a hole 233a formed along the axial direction of the main frame 10 is provided in the substantially center of the center yoke 233. The suspension 260 is linked to the vibrating portion 230 by the protrusion 262 being inserted in the hole 233a. As a result, the suspension 260 specifies the position of the vibrating portion 230, and restricts the vibration of the vibrating portion 230 in the Y direction. According to this configuration, the position of the vibrating portion 230 is determined by the suspension 260, so assembly is easy.

[0071] • Electro-acoustic transducer (4)

[0072] Figure 8 and Figure 9 The electro-acoustic transducer 301 of the fourth embodiment shown differs from the previously explained embodiments in that it has a plurality of elastic members 320. The elastic members 320 include a small member 320a disposed on the bottom surface of the cover-shaped yoke 31, and small members 320b, 320c, 320d, 320e disposed at a gap from each other along the circumferential direction of the cover-shaped yoke 31. The small members 320b to 320e are four in number in this embodiment, but the number is not limited thereto. In addition, an appropriate linking member that links the small members 320a to 320e can also be provided. This elastic member 320 is preferably a gel material that is a comparatively hard member. According to this configuration, the contact area of the elastic member 320 is smaller than that of the elastic member 120 of the bottomed cylindrical body, and the vibrating portion 30 can be made to vibrate more greatly.

[0073] • Electro-acoustic transducer (5)

[0074] Figure 10 and Figure 11 The electro-acoustic transducer 401 of the fifth embodiment shown is provided with a bottomed cylindrical unit base 450. The unit base 450 has a side wall 451 that projects in a manner covering the side surface of the vibrating portion 30. On the inner peripheral surface of the side wall 451, the elastic member 20 is linked. In addition, the elastic member 20 is linked to the cover-shaped yoke 31 that constitutes the outer periphery of the vibrating portion 30. According to this configuration, the side wall 451 of the unit base 450 corresponds to the cylindrical portion of the main frame, and no additional member is needed, so the configuration can be simplified.

[0075] • Electro-acoustic transducer (6)

[0076] Figure 12 and Figure 13The electroacoustic transducer 501 of the sixth embodiment shown includes a housing 570 that houses the vibrating portion 30. The housing 570 houses the elastic member 20, the vibrating portion 30, the coil 40, and the unit base 50, for example, by fitting an upper housing 570a and a lower housing 570b together. The housing 570 is generally rectangular in shape in the figure, but is not limited thereto and can be any appropriate shape that matches the outer shape of the earphone 1000.

[0077] like Figure 13 As shown in (a), a protruding rib 571 is formed on the inner side of the upper shell 570a. The rib 571 is, for example, cylindrical corresponding to the elastic component 20, but is not limited to this. For example, it can also be composed of a plurality of protrusions. The elastic component 20 is connected to the inner side of the rib 571. The elastic component 20 can be bonded to the rib 571, for example. With this structure, the rib 571 of the upper shell 570a is equivalent to the cylindrical part of the main frame, and no additional components are required, thereby simplifying the structure.

[0078] ●Electroacoustic Converter(7)●

[0079] Figure 14 as well as Figure 15 The electroacoustic transducer 601 of the seventh embodiment shown is different from the previously described embodiment in that a cylindrical elastic member 620 and an axis member 660 inserted into the elastic member 620 are arranged at the end of the vibration direction of the vibration part 30. The radius of the elastic member 620 is smaller than the inner diameter of the coil 40. The elastic member 620 and the axis member 660 are connected to the surface of the center magnetic yoke 33 facing the vibration direction on the radial inner side of the main frame 10 and the coil 40. In addition, the elastic member 620 is embedded in the hole 651 formed in the unit base 650. The elastic member 620 is preferably made of a harder material than the previous elastic member 20. With this structure, the vibration of the vibration part 30 in the Y direction can also be limited. In addition, according to this structure, the electroacoustic transducer 601 can be constructed with a smaller number of components.

[0080] ●Electroacoustic Converter(8)●

[0081] Figure 16 The electroacoustic transducer 701 of the eighth embodiment shown differs from the previously described embodiments in that elastic members 720 are disposed before and after the vibration portion 730 in the vibration direction. The electroacoustic transducer 701 includes a housing 770 that accommodates the vibrating portion 730. The housing 770 is composed, for example, of an upper housing 770a, which forms the upper portion of the housing 770 in the figure, and a lower housing 770b, which forms the lower portion of the housing 770 in the figure. The housing 770 is another example of a main frame.

[0082] The inner side of the housing 770 mainly accommodates the coil 40, the vibrating portion 730 inserted into the coil, and the elastic member 720. The coil 40 is fixed to the inner side of the housing 770. The vibrating portion 730 is composed of, for example, a magnet 733 and a center yoke 760. The vibrating portion 730 is, for example, a structure in which two magnets 733 clamp the center yoke 760. In this case, the two magnets 733 make the same poles face each other, that is, make the S poles face each other or the N poles face each other, and clamp the center yoke 760. According to this structure, the sensitivity can be improved compared to a structure in which both the magnet and the center yoke are provided.

[0083] The elastic components 720 are respectively arranged in front and behind the vibration direction of the vibration part 730. In addition, the elastic component 720 can be arranged only on either the front or rear side of the vibration direction. The first end of the elastic component 720 is connected to the inner side of the shell 770, and the second end is connected to the vibration part 730. If current flows into the coil 40, the vibration part 730 deforms the elastic component 720 while vibrating mainly in the up and down directions in the figure. According to this structure, it can be achieved with a simple structure with a small number of components. In addition, due to the simple structure, it can be firmly constructed. In addition, by selecting the material of the elastic component 720, the acoustic characteristics can be adjusted. For example, by selecting a material with a small recovery coefficient, severe resonance can be suppressed.

[0084] ●Electroacoustic Converter(9)●

[0085] Figure 17 The electroacoustic converter 801 of the ninth embodiment shown is different from the previously described embodiments in that instead of Figure 16 The vibrating portion 730 shown has a magnet 833 coupled to a center yoke 860. In this case, as shown in the figure, the coil 40 can be positioned close to the end of the vibrating portion 830 in the vibration direction, in accordance with the position of the center yoke 860. This configuration also enables the realization of an electroacoustic transducer 801 that suppresses unintended vibrations while providing high sound quality.

[0086] The above-mentioned structure can also provide a high-quality electroacoustic transducer that generates bone conduction vibration while reducing abnormal noise.

[0087] As mentioned above, although the present invention has been described using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments, and various modifications and changes can be made within the scope of the gist of the invention.

[0088] Description of Reference Signs

[0089] 1 electroacoustic converter

[0090] 10 Main structure

[0091] 20 elastic components

[0092] 30 oscillating portion

[0093] 40 coil

[0094] 50 unit base

[0095] 1000 earphone

Claims

1. An electroacoustic transducer that transmits vibrations to bones, wherein: include: a main frame having at least a cylindrical portion; a vibrating portion disposed inside the main frame and vibrating along an axial direction of the main frame according to an input signal; and The elastic member is connected to at least the vibration part and is formed of an organic substance or a polymer material.

2. The electroacoustic converter according to claim 1, wherein The elastic member exerts the elastic force due to its porous structure.

3. The electroacoustic converter according to claim 1, wherein The elastic member is connected to an outer peripheral surface of the vibrating portion along a vibration direction and an inner peripheral surface of the main frame.

4. The electroacoustic converter according to claim 3, wherein The elastic member is a cylindrical member disposed along the entire circumference of the vibrating portion.

5. The electroacoustic converter according to claim 3, wherein A plurality of elastic members are provided.

6. The electroacoustic converter according to claim 1, wherein The main frame is a bottomed cylindrical body formed by connecting a bottom to the cylindrical portion. The first surface of the vibrating portion facing the vibration direction is opposite to the bottom. The elastic member is connected to at least the bottom portion.

7. The electroacoustic converter according to claim 6, wherein The elastic member is connected to the outer periphery of the vibrating portion and is connected to the cylindrical portion and the bottom portion of the main frame.

8. The electroacoustic converter according to claim 1, wherein It also has a unit base covering the second surface of the vibration part facing the vibration direction, The unit base has a side wall extending so as to cover the side surface of the vibration part. The elastic member is connected to the outer periphery of the vibration portion and the inner periphery of the side wall of the unit base.

9. The electroacoustic converter according to claim 1, wherein A housing for accommodating the vibration unit is provided. The elastic member is connected to the housing.

10. The electroacoustic converter according to claim 1, wherein The elastic member is connected to the second surface of the vibrating portion facing the vibration direction.

11. The electroacoustic converter according to claim 1, wherein It also includes a suspension, which is locked with the first end of the main frame to hold the vibrating part. The suspension includes a protrusion that is inserted into the vibrating portion along the axial direction of the main frame.

12. A headset, wherein: include: headband; and A pair of electroacoustic converters are respectively held at both ends of the headband, The electroacoustic converter is the electroacoustic converter according to any one of claims 1 to 11.

Images