Transducer and listening device

Abstract

A vibrator (1) has: a magnetic yoke (11) having an upper end side opening, and having a bottom surface portion and a peripheral wall portion; a coil holder (4) disposed at least partially inside the magnetic yoke (11); a coil (5) wound outside the coil holder (4); a magnet (6, 8) disposed inside the coil holder (4); a damper (10) that supports the magnetic yoke (11); a frame (9) that fixes the damper (10) to the magnetic yoke (11); and a case (2) that houses the magnetic yoke (9), the coil holder (4), the coil (5), the magnet (6, 8), the damper (10), and the frame (9). An outer edge portion of the damper (10) is fixed to the case (2). A lower surface of an inner edge portion of the damper (10) abuts an upper end of the peripheral wall portion of the magnetic yoke (11). The frame (9) is rivet-fixed to the damper (10) and the magnetic yoke (11) in a manner that an upper surface of the inner edge portion of the damper (10) and an inner surface of the peripheral wall portion of the magnetic yoke (11) abut, respectively.

Description

Technical Field

[0001] This invention relates to an oscillator and a listening device. Background Technology

[0002] In the past, various devices that transmit vibrations to objects and can recognize sound have been proposed, such as bone conduction devices, bone conduction loudspeakers, or bone conduction oscillators (Patent Documents 1 to 5).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2003-150542

[0006] Patent Document 2: Japanese Patent No. 6618230

[0007] Patent Document 3: Japanese Patent Application Publication No. 2015-186102

[0008] Patent Document 4: Japanese Patent Application Publication No. 2016-116177

[0009] Patent Document 5: Japanese Patent Application Publication No. 2018-117203 Summary of the Invention

[0010] The problem that the invention aims to solve

[0011] However, there are many issues regarding these devices that require further research.

[0012] In view of the above, the objective of the present invention is to provide a more useful oscillator and a listening device.

[0013] Solution for solving the problem

[0014] To achieve the above-mentioned objectives, the oscillator of the present invention comprises: a magnetic yoke with an opening at its upper end and having a bottom portion and a peripheral wall portion; a coil frame, at least a portion of which is disposed inside the magnetic yoke; a coil wound around the outer side of the coil frame; a magnet, at least a portion of which is disposed inside the coil frame; a damper supporting the magnetic yoke; a frame fixing the damper to the magnetic yoke; and a housing housing the magnetic yoke, the coil frame, the coil, the magnet, the damper, and the frame, wherein the outer edge of the damper is fixed to the housing, the lower surface of the inner edge of the damper abuts against the upper end of the peripheral wall portion of the magnetic yoke, and the frame is riveted to the damper and the magnetic yoke such that it abuts against the upper surface of the inner edge of the damper and the inner surface of the peripheral wall portion of the magnetic yoke, respectively.

[0015] In addition, in this invention, the upper end of the coil frame abuts against the inner surface of the housing.

[0016] In addition, the present invention also has a top plate disposed on the inner side of the coil frame, and the magnet includes a first magnet and a second magnet, the first magnet being disposed on the top plate and the second magnet being disposed below the top plate.

[0017] In addition, in this invention, the shape of the lower part of the inner side of the magnetic yoke corresponds to the shape of the lower end side of the second magnet, so as to fix the lower end side of the second magnet to the inner side of the magnetic yoke.

[0018] In addition, in this invention, the frame and the magnetic yoke are formed of a soft magnetic material.

[0019] Furthermore, in this invention, at least a portion of the peripheral wall portion of the frame and the yoke is opposite to the coil.

[0020] In addition, in this invention, the damper has a through hole extending in the vertical direction.

[0021] In addition, in this invention, the housing includes an upper housing and a lower housing, and the outer edge of the damper is sandwiched between the upper housing and the lower housing.

[0022] Additionally, in this invention, the upper housing has wiring holes for allowing cables to pass through.

[0023] Furthermore, in this invention, a blocking component is provided to block the wiring hole, and the housing is sealed.

[0024] The hearing device of the present invention has any one of the above-mentioned oscillators as a cartilage conduction oscillator for transmitting sound signals to the auricular cartilage.

[0025] Invention Effects

[0026] As described above, according to the present invention, a more useful oscillator and a listening device are provided. Attached Figure Description

[0027] Figure 1 This is a perspective view of the vibrator of the listening device according to an embodiment of the present invention.

[0028] Figure 2 This is a side view of the vibrator of the listening device according to an embodiment of the present invention.

[0029] Figure 3 This is a bottom view showing the vibrator of the listening device according to an embodiment of the present invention.

[0030] Figure 4 This is a rear view of the vibrator of the listening device according to an embodiment of the present invention.

[0031] Figure 5 This is a diagram showing the internal structure of the oscillator of the listening device according to an embodiment of the present invention.

[0032] Figure 6 This is an exploded perspective view of the vibrator of the listening device according to an embodiment of the present invention.

[0033] Figure 7 This is a plan view of the damper of the oscillator of the listening device according to an embodiment of the present invention.

[0034] Figure 8 This is a side view showing the state in which the vibrator of the listening device according to an embodiment of the present invention is connected to a cable.

[0035] Figure 9 This is a perspective view showing an example of another shape of the vibrator of the listening device according to an embodiment of the present invention.

[0036] Figure 10 This is a perspective view showing an example of another shape of the vibrator of the listening device according to an embodiment of the present invention.

[0037] Figure 11 It is an anatomical diagram of the ear.

[0038] Figure 12 This is a graph representing an example of measured data on the effect of cartilage conduction.

[0039] Figure 13 This is a diagram illustrating how to use a listening device. Detailed Implementation

[0040] <Vibration>

[0041] Figure 1 This is a perspective view of the vibrator 1 of the listening device according to an embodiment of the present invention. Figure 2 This is a side view of oscillator 1. Figure 3 This is a bottom view of oscillator 1. Figure 4 This is a rear view of oscillator 1.

[0042] The housing 2 of the oscillator 1 is composed of an upper housing 2a and a lower housing 2b. The upper housing 2a and the lower housing 2b are fixed together by an adhesive or the like. A protrusion 2c is formed on the upper housing 2a. The housing 2 is formed of resin (e.g., ABS resin).

[0043] The protrusion 2c of the upper housing 2a has a wiring hole 2d for the cable 12 to pass through. Figure 8 This is a side view showing the state of the oscillator 1 with cable 12 connected.

[0044] The surface of the housing 2, excluding the protrusion 2c, is curved. As illustrated, the portion of the housing 2 excluding the protrusion 2c has a spherical or near-spherical shape. "Spherical" includes not only a perfect sphere but also a near-sphere within a certain margin of error. When the vibrator 1 is worn on the user's ear, the portion of the housing 2 extending from its lower end to the protrusion 2c, at a distance W1, hooks onto the ear. For stable wearing of the vibrator 1, a larger distance W1 is preferable. For example, the vertical distance W2 of the protrusion 2c is considered to be less than half of the vertical distance W3 of the upper housing 2a. Furthermore, for example, the protrusion 2c preferably extends along the tangential direction of the upper housing 2.

[0045] Figure 5 This is a diagram showing the internal structure of the oscillator 1 of the listening device according to an embodiment of the present invention (a partial cross-sectional view with a portion of the oscillator 1 removed). Figure 6 This is an exploded perspective view of the vibrator 1 of the listening device according to an embodiment of the present invention.

[0046] The coil frame 4, coil 5, magnets (first magnet 6, second magnet 8), top plate 7, frame 9, damper 10, magnetic yoke 11, and base plate 3 are housed in the housing 2.

[0047] A coil 5 is wound around the outside of the coil frame 4. The coil frame 4 is longer in the vertical direction, and its upper end abuts against the inner surface of the housing 2 (upper housing 2a). An electrical signal (such as a sound signal) is input to the coil 5. The coil frame 4 is made of kraft paper or the like, and the coil 5 is made of copper or the like.

[0048] Additionally, substrate 3 is mounted on the inner surface of housing 2 (upper housing 2a). Cable 12 is connected to substrate 3. Figure 8 ), and connected to the end side of coil 5 (not shown) or to the wiring connected to coil 5 (not shown).

[0049] The substrate 3 is close to the wiring hole 2d, so the cable 12 can be easily connected to the substrate 3. In addition, the coil holder 4 is formed in a longitudinal shape with its upper end abutting against the inner surface of the substrate 3 and the housing 2 (upper housing 2a), so the end side of the coil 5 (not shown) or the wiring (not shown) connected to the coil 5 can be easily connected to the substrate 3.

[0050] At least a portion of the magnets (first magnet 6 and second magnet 8) are disposed inside the coil frame 4. The magnets include the first magnet 6 and the second magnet 8. The first magnet 6 and the second magnet 8 are, for example, neodymium magnets.

[0051] The top plate 7 is located inside the coil holder 4. The first magnet 6 is located on the top plate 7. The second magnet 8 is located below the top plate 7. The top plate 7 is made of iron (SPCC, etc.).

[0052] The magnetic yoke 11 has an opening at its upper end and includes a bottom portion and a peripheral wall portion. The shape of the lower part of the inner side of the magnetic yoke 11 corresponds to the shape of the lower end of the second magnet 8, thereby fixing the lower end of the second magnet 8 to the inner side of the magnetic yoke 11. Therefore, positioning the second magnet 8 becomes easy. The magnetic yoke 11 is formed of a soft magnetic material (SPCC, etc.).

[0053] At least a portion of the coil frame 4 is disposed inside the magnetic yoke 11.

[0054] The outer edge of the damper 10 is fixed to the housing 2 and is sandwiched between the upper housing 2a and the lower housing 2b. That is, the outer edge of the damper 10 is held between the upper housing 2a and the lower housing 2b. The lower surface of the inner edge of the damper 10 abuts against the upper end of the peripheral wall of the magnetic yoke 11. The damper 10 is, for example, made of stainless steel. Figure 7 As shown, the damper 10 has a through hole 10a extending vertically. Multiple cutouts 10b are formed around the periphery of the damper 10. Multiple recesses 2e are formed in the upper housing 2a, and multiple protrusions 2f are formed in the lower housing 2b. The recesses 2e and protrusions 2f combine at the cutouts 10b. As a result, the damper 10 is mounted between the upper housing 2a and the lower housing 2b.

[0055] The frame 9 secures the damper 10 to the yoke 11. Specifically, the frame 9 is riveted to the damper 10 and the yoke 11 in a manner that abuts against the upper surface of the inner edge of the damper 10 and the inner surface of the peripheral wall of the yoke 11, respectively. The frame 9 is formed of a soft magnetic material (such as SPCC [steel plate cold commercial]).

[0056] If the damper 10 is fixed to the yoke 11 using adhesives or the like (without using frame 9), the fixation of the damper 10 and the yoke 11 is unstable. However, since the damper 10 is fixed to the yoke 11 using frame 9, it is easy to fix the damper 10 and the yoke 11. That is, this fixation of the damper 10 and the yoke 11 using frame 9 is suitable for mass production.

[0057] Additionally, the frame 9 secures the damper 10 to the yoke 11, thereby supporting the yoke 11. The yoke 11 is suspended inside the housing 2 by the damper 10 and the frame 9. That is, the yoke 11 is detached from the inner surface of the housing 2.

[0058] If the yoke is fixed to the inner surface of the housing using adhesives or the like, vibrations may not be perceptible across the entire frequency band, resulting in the inability to hear only high frequencies (e.g., above 5 kHz). In this embodiment, the yoke 11 is removed from the inner surface of the housing 2, thus avoiding this problem.

[0059] Furthermore, at least a portion of the peripheral wall of the frame 9 and the yoke 11 is opposite to the coil 5. In this structure, magnetic flux is easily concentrated in the coil 5. In particular, the frame 9 and the yoke 11 are formed of a soft magnetic material (SPCC, etc.), which facilitates the concentration of magnetic flux in the coil 5. When the magnetic flux is concentrated (the magnetic flux density increases), the driving force for vibration increases, making it easier to generate vibration.

[0060] Furthermore, if the housing has holes, sound will leak from the holes when the oscillator vibrates. To prevent sound leakage, it is preferable to seal the housing.

[0061] Therefore, housing 2 can also be sealed. When housing 2 is sealed, a plugging component (not shown) that blocks the wiring hole 2d can also be used.

[0062] However, when the casing is sealed and the vibrating plate (damper, etc.) inside the casing is shaped without holes, vibration is difficult to generate. In particular, when the casing is small, the vibrating plate cannot move due to the air pressure inside the casing. In addition, the space inside the casing is divided into an upper space and a lower space by the vibrating plate. For example, even if the vibrating plate wants to move downwards, the air in the lower space cannot move to the upper space. Therefore, the vibrating plate cannot vibrate, or the vibration amplitude of the vibrating plate is small.

[0063] In this embodiment, a through hole 10a is formed in the damper 10. Air on the upper side of the damper 10 can move to the lower side of the damper 10 through the through hole 10a. Conversely, air on the lower side of the damper 10 can move to the upper side of the damper 10 through the through hole 10a. The movement of air within the housing 2 is unrestricted. Therefore, the damper 10 can vibrate significantly not only when the housing 2 is not sealed, but also when the housing 2 is a sealed space. Thus, even when the housing 2 is small and sealed, the damper 10 can vibrate significantly.

[0064] Not only when the housing 2 is not sealed, but also when the housing 2 is sealed, the damper 10 can vibrate significantly, so the housing 2 can vibrate sufficiently. Therefore, sufficient vibration can be transmitted to the user of the oscillator 1.

[0065] Additionally, the housing vibrates through the vibration of a damper or magnetic yoke. The vibrating housing comes into contact with the user, transmitting vibrations to the user, who then perceives the sound. On the other hand, when the housing vibrates, the air surrounding it vibrates, generating airborne sound. In the case of housing 2, the small surface area suppresses airborne sound. Therefore, it is possible to transmit vibrations to the user while simultaneously suppressing airborne sound leakage into the user's surroundings.

[0066] With housing 2 sealed, water or sweat will not enter housing 2. The use of a sealed housing can be applied to waterproof oscillators.

[0067] The damper 10 can also be formed from liquid metal. The damper 10 may break due to repeated vibration. Although liquid metal is a metal, it has elasticity and is not easily fatigued. When the damper 10 is formed from liquid metal, the damper 10 can be used for a long time.

[0068] Furthermore, the damper 10 is disposed at the center of the housing 2 in the vertical direction. The housing 2 is formed into a spherical or near-spherical shape without increasing its size. Moreover, "center" includes not only the exact center but also a substantial center within a certain tolerance range. The shape of the housing can also be other shapes, and it does not have to be a spherical or near-spherical shape like the housing 2. Figure 9 This is a three-dimensional diagram showing an example of another shape of an oscillator. Figure 10 This is a perspective view showing another example of the shape of the oscillator. For example, housing 13 can also be used instead of housing 2. Figure 9 ) or housing 14 ( Figure 10 In the case where a shell of a different shape is used instead of shell 2, the shapes of various components such as dampers or yokes are appropriately changed in a manner corresponding to the shape of the shell.

[0069] The vibrator 1 can also be used as a cartilage conduction vibrator. Therefore, it is preferable that the hearing device of the present invention has the above-described vibrator 1 as a cartilage conduction vibrator for transmitting sound signals to the ear cartilage.

[0070] <Cartilage conduction>

[0071] Next, refer to Figure 11 The listening mechanism of the listening device with oscillator 1 is explained. Furthermore, Figure 11 It is an anatomical diagram of the ear.

[0072] As an otolaryngologist, the inventor of this application has, for the first time in the world, discovered the following novel hearing mechanism (a third hearing mechanism that is neither air conduction nor bone conduction, see reference). Figure 11The thick solid arrow indicates that this mechanism is named cartilage conduction and proposed for use in mobile phones or hearing aids. This new hearing mechanism is that when a vibrator is pressed against the cartilaginous tissue of the auricle X2 surrounding the external auditory canal opening X1a, such as the tragus X2a or the auricular cartilage X2b distributed on the dorsal side of the auricle X2 (especially the part near the external auditory canal opening X1a), its vibration is transmitted to the cartilaginous part of the external auditory canal X1b (approximately half of the external auditory canal X1 near the anterior side of the external auditory canal opening X1a). The air-conducted sound (compression waves of air caused by sound vibration) generated from the inner surface of the cartilaginous part of the external auditory canal X1b reaches the tympanic membrane X3 via the bony part of the external auditory canal X1c (approximately half of the external auditory canal X1 near the depth side of the tympanic membrane X3), thereby enabling the hearing of sound.

[0073] If it is the cartilage conduction described above, it is different from the existing bone conduction that causes the heavy anterior and lateral skull to vibrate. It can cause the lighter tragus X2a and auricular cartilage X2b to vibrate and hear sound, so the driving energy of the oscillator is very small.

[0074] Furthermore, in cartilage conduction, unlike existing air conduction (the phenomenon where sound can be heard by vibrating the tympanic membrane X3 through the conduction of sound through air entering from the outside of the external auditory canal X1a), the following phenomenon can be observed: when the external auditory canal X1a is blocked with a finger or the like, the sound energy inside the external auditory canal X1 increases, allowing the sound to be heard loudly (external auditory canal blockage effect). Therefore, by blocking the external auditory canal X1a, sound can be heard clearly even in noisy environments.

[0075] Figure 12 This is a graph showing an example of measured data representing the effect of cartilage conduction. This graph shows the sound pressure in the external auditory canal at a depth of 1 cm from the entrance of the external auditory canal when the outer wall surface of the vibrator vibrating through the cartilage conduction vibration source contacts at least a portion of the auricular cartilage around the entrance of the external auditory canal without contacting the helix.

[0076] Furthermore, the vertical axis of this graph represents sound pressure (dBSPL), and the horizontal axis represents frequency (Hz) on a logarithmic scale. Additionally, to illustrate the effect of the contact pressure between the outer surface of the vibrator and the auricular cartilage surrounding the entrance to the external auditory canal on the sound pressure within the canal, solid lines represent the sound pressure in the non-contact state (i.e., only air-conducted sound generated from the outer surface of the vibrator can be heard), dashed lines represent the sound pressure at a contact pressure of 10 grams, a single-dotted line represents the sound pressure at a contact pressure of 250 grams, and a double-dotted line represents the sound pressure under conditions of further increase in contact pressure leading to external auditory canal blockage (contact pressure of 500 grams).

[0077] As shown in the figure, the sound pressure increases from the non-contact state by contacting the object with a pressure of 10 grams, then by increasing the contact pressure to 250 grams, and finally by increasing the contact pressure to 500 grams, thus further increasing the sound pressure.

[0078] According to this graph, when the outer wall surface of the vibrator contacts at least a portion of the auricular cartilage around the entrance of the external auditory canal without contacting the helix, the sound pressure in the external auditory canal at a depth of 1 cm from the entrance of the external auditory canal increases by at least 10 dB in the main frequency band of sound (500 Hz to 2300 Hz) compared to the non-contact state (compare the non-contact state shown by the solid line and the state shown by the dashed line).

[0079] Furthermore, according to this graph, when the outer wall surface of the vibrator contacts at least a portion of the auricular cartilage around the entrance of the external auditory canal without contacting the helix, the sound pressure in the external auditory canal 1 cm deep from the entrance of the external auditory canal changes by at least 5 dB in the main frequency band of sound (500 Hz to 2500 Hz) according to the change in contact pressure (compare the contact state shown by the dashed line and the contact state shown by the single-dot dashed line).

[0080] As can be seen from the above, even without an air-conducting sound-generating mechanism (e.g., the diaphragm of a typical headphone), the vibration of the cartilage-conducting vibration source can be transmitted to the ear cartilage through contact, thereby obtaining the required sound pressure. Furthermore, it is known that since hearing is achieved by contacting the vibrator with the ear cartilage surrounding the entrance to the external auditory canal, keeping the external auditory canal open and not blocked allows for hearing external sounds while simultaneously hearing sounds from the vibrator, resulting in a comfortable wearing experience without the feeling of blockage in the external auditory canal.

[0081] Furthermore, as shown in this graph, when the external auditory canal is blocked by making the outer wall surface of the vibrator more forcefully contact at least a portion of the auricular cartilage (in the actual measurement shown in this graph, the outer wall surface of the vibrator was pressed from the outside of the tragus, causing the tragus to bend, thus creating a state of external auditory canal blockage), the sound pressure in the external auditory canal at a depth of 1 cm from the entrance of the external auditory canal increases by at least 20 dB in the main frequency band of sound (300 Hz to 1800 Hz) compared to the non-contact state. This indicates a significant sound pressure enhancement effect produced by the external auditory canal blockage effect (compare the non-contact state shown by the solid line and the external auditory canal blockage state shown by the two-dot dashed line).

[0082] Furthermore, all measurements in this graph were performed with the output of the cartilage-conducting vibration source remaining unchanged. Additionally, as for the condition where the outer surface of the vibrator contacts at least a portion of the auricular cartilage surrounding the entrance to the external auditory canal without contacting the helix, the measurements in this graph were performed with the outer surface of the vibrator contacting the tragus from the outside. Furthermore, the measurements in this graph under the condition of external auditory canal obstruction were performed by pressing the tragus more forcefully from the outside, as described above, causing the tragus to fold back, thereby creating a state of obstruction of the external auditory canal.

[0083] Furthermore, this graph is merely an example, and individual differences may exist upon close observation. Additionally, to simplify and standardize the phenomenon, this graph was measured with the outer surface of the vibrating body in contact only with the outer side of the tragus, resulting in a small contact area.

[0084] However, the increase in sound pressure caused by contact also depends on the contact area with the auricular cartilage. When the outer surface of the vibrator contacts the auricular cartilage around the entrance of the external auditory canal without contacting the helix, the increase in sound pressure is further enhanced if a wider portion of the auricular cartilage around the entrance of the external auditory canal is contacted. Taking the above into account, the values ​​shown in this graph have general applicability to structures utilizing cartilage conduction and are reproducible to a specific majority of subjects.

[0085] Moreover, this graph shows that when the external auditory canal is blocked, the contact pressure is increased by pressing the tragus from the outside to fold the tragus back. However, the same result can be obtained when the outer wall surface of the vibrator is pressed into the entrance of the external auditory canal to block the external auditory canal.

[0086] <How to use the hearing device>

[0087] Figure 13 This diagram illustrates how a hearing device is used. The hearing device in this diagram is used, for example, as a headset, hearing aid, or sound collector for a smartphone or portable music player, and includes the aforementioned vibrator 1 as a cartilage vibrator.

[0088] The vibrator 1 generates vibrations corresponding to the sound signal (i.e., an electrical signal containing sound information) and transmits them to the cartilage tissue surrounding the external auditory canal opening X1a. As shown in this figure, the vibrator 1 is formed into a spherical shape housed within the intertragic notch X2d (i.e., the lower part of the concha cavity) sandwiched between the tragus X2a and the antitragus X2c. By transmitting vibrations to the cartilage tissue in contact with the vibrator 1, the user hears the sound.

[0089] If used in this way, a stable and extremely natural sound can be achieved.

[0090] <Other variations>

[0091] Furthermore, the various technical features disclosed in this specification, in addition to the embodiments described above, can be modified in various ways without departing from the spirit of the invention. That is, the embodiments described above should be considered illustrative rather than limiting in all respects, and the scope of the invention is defined by the claims, which should be understood to include all modifications falling within the meaning and scope equivalent to the claims.

[0092] Production availability

[0093] The inventions disclosed in this specification are, for example, headphones that can be used in smartphones or portable music players, or hearing aids or sound collectors.

[0094] Symbol Explanation

[0095] 1—Vibrator; 2, 13, 14—House; 3—Base plate; 4—Coil frame; 5—Coil; 6—Magnet (first magnet); 7—Top plate; 8—Magnet (second magnet); 9—Frame; 10—Damper; 10a—Through hole; 11—Magnetic yoke; 12—Cable; X1—External auditory canal; X1a—External auditory canal opening; X1b—Cartilaginous external auditory canal; X1c—Bony external auditory canal; X2—Auricle; X2a—Tragus; X2b—Auricular cartilage on the dorsal side of the auricle; X2c—Antitragus; X2d—Intertragusal notch; X3—Tympanic membrane.

Claims

1. An oscillator, characterized in that, have: A magnetic yoke, which has an opening at its upper side and has a bottom part and a peripheral wall part; A coil frame, at least a portion of which is disposed inside the yoke; A coil, which is wound around the outside of the coil frame; A magnet, at least a portion of which is disposed on the inside of the coil frame; A damper that supports the magnetic yoke; A frame that secures the damper to the magnetic yoke; as well as A housing that houses the magnetic yoke, the coil frame, the coil, the magnet, the damper, and the frame. The outer edge of the damper is fixed to the housing. The lower surface of the inner edge of the damper abuts against the upper end of the peripheral wall of the magnetic yoke. The frame is riveted to the damper and the magnetic yoke in such a manner that it abuts against the upper surface of the inner edge of the damper and the inner surface of the peripheral wall of the yoke, respectively.

2. The oscillator according to claim 1, characterized in that, The upper end of the coil frame abuts against the inner surface of the housing.

3. The oscillator according to claim 1, characterized in that, It also has a top plate disposed on the inner side of the coil frame. The magnets include a first magnet and a second magnet. The first magnet is disposed on the top plate. The second magnet is disposed under the top plate.

4. The oscillator according to claim 3, characterized in that, The shape of the lower part of the inner side of the magnetic yoke corresponds to the shape of the lower end side of the second magnet, so as to fix the lower end side of the second magnet to the inner side of the magnetic yoke.

5. The oscillator according to claim 1, characterized in that, The frame and the magnetic yoke are formed of soft magnetic material.

6. The oscillator according to claim 5, characterized in that, At least a portion of the peripheral wall of the frame and the yoke is opposite to the coil.

7. The oscillator according to claim 1, characterized in that, The damper has a through hole running vertically through the device.

8. The oscillator according to any one of claims 1 to 7, characterized in that, The housing includes an upper housing and a lower housing. The outer edge of the damper is clamped between the upper housing and the lower housing.

9. The oscillator according to claim 8, characterized in that, The upper housing has wiring holes for cables to pass through.

10. The oscillator according to claim 9, characterized in that, The housing is sealed by a blocking component that blocks the wiring hole.

11. A listening device, characterized in that, The oscillator according to any one of claims 1 to 10 is used as a cartilage conduction oscillator for transmitting sound signals to the auricular cartilage.

Images