Driver unit

Abstract

To enable suppression of total harmonic distortion caused by a ventilation member in a driver unit.SOLUTION: The driver unit includes: a diaphragm; a driver unit body having a vent hole formed in a rear side of the diaphragm; a ventilation member (2) for covering the vent hole from the outer side of the driver unit body; and a reinforcing member (3) for reinforcing the ventilation member (2). The ventilation member (2) has an annular mounting part (21) for being attached to a peripheral region where the vent hole opens of the outer surface of the driver unit body. The reinforcing member (3) has a plurality of strip-shaped parts (31) extending in mutually different directions from the center (O) of the ventilation member (2) to the mounting part (21) when viewed in a direction in which the vent hole and the ventilation member (2) overlap.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a driver unit. [Background technology]

[0002] Patent Document 1 discloses a headphone driver unit. The driver unit in Patent Document 1 has a ventilation member (airflow register) that covers the ventilation holes formed on the back side of the diaphragm. The ventilation member is provided to adjust the frequency characteristics of the diaphragm. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 11,082,768 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, in a driver unit having a ventilation member, it is desirable to suppress total harmonic distortion (hereinafter also referred to as THD) caused by the ventilation member.

[0005] The present invention has been made in view of the above circumstances, and has an object to provide a driver unit that is capable of suppressing total harmonic distortion caused by a ventilation member. [Means for solving the problem]

[0006] A first aspect of the present invention is a driver unit comprising a diaphragm and a driver unit main body having an air vent formed on the back side of the diaphragm, a ventilation member that covers the air vent from the outside of the driver unit main body, and a reinforcing member that reinforces the ventilation member, wherein the ventilation member has an annular mounting portion that is attached to the peripheral region of the outer surface of the driver unit main body where the air vent opens, and the reinforcing member has a plurality of strip-shaped portions that extend in different directions from the center of the ventilation member to the mounting portion when viewed from the direction in which the air vent and the ventilation member overlap.

[0007] A second aspect of the present invention comprises a driver unit main body having a diaphragm and an air vent formed on the back side of the diaphragm, a ventilation member that covers the air vent from the outside of the driver unit main body, and a reinforcing member that reinforces the ventilation member, wherein the ventilation member has an annular mounting portion that is attached to the peripheral region of the outer surface of the driver unit main body where the air vent opens, and the reinforcing member is a driver unit that suppresses vibration of the ventilation member. [Effects of the Invention]

[0008] According to the present invention, total harmonic distortion caused by the ventilation member in the driver unit can be suppressed. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 2 is a cross-sectional view showing a driver unit according to one embodiment of the present invention. [Figure 2] FIG. 2 is an exploded perspective view showing the driver unit of FIG. [Figure 3] 3 is a plan view showing a ventilation member to which a reinforcing member and a fixing member are attached in the driver unit of FIGS. 1 and 2.

[0023] FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along the line IV-IV in FIG. 3. [Figure 5] 10 is a graph showing frequency characteristics of an example and a comparative example of a driver unit. [Figure 6]10 is a plan view of a modified example of a ventilation member to which a reinforcing member and a fixing member are attached, viewed from the opposing surface side of the ventilation member. FIG. [Figure 7] 7 is a plan view of the ventilation member of FIG. 6, viewed from the opposite surface side of the ventilation member. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, one embodiment of the present invention will be described with reference to FIGS. 1 to 4, driver unit 100 of this embodiment includes a driver unit main body 1, a ventilation member 2, a reinforcing member 3, and a fixing member 4. Reinforcing member 3 and fixing member 4 are provided on ventilation member 2, and are not shown in FIGS.

[0011] 1, the driver unit main body 1 has a diaphragm 11 and an air vent 10 formed on the rear surface 11b side of the diaphragm 11. In the driver unit main body 1, sound is generated when the diaphragm 11 vibrates in response to an electrical signal input from the outside. As shown in FIGS. 1 and 2, the driver unit body 1 of this embodiment has a diaphragm 11, a frame 12, a voice coil 13, a pole piece 14, a magnet 15, a pot yoke 16, and a protector 17.

[0012] The frame 12 holds the diaphragm 11, voice coil 13, pole piece 14, magnet 15, pot yoke 16, and protector 17 in their appropriate locations. The frame 12 of this embodiment is generally cylindrical. Specifically, the frame 12 has a cylindrical large-diameter portion 121, a cylindrical small-diameter portion 122, and a flange portion 123. The large-diameter portion 121 and the small-diameter portion 122 are aligned adjacent to each other along their axis (hereinafter referred to as the axial direction). The diameter of the large-diameter portion 121 is larger than that of the small-diameter portion 122. The flange portion 123 is formed in a ring shape, extending radially outward from the end of the small-diameter portion 122 located on the large-diameter portion 121 side in the axial direction and reaching the large-diameter portion 121. The flange portion 123 has a plurality of through-holes 124 formed therethrough in the axial direction. These through-holes 124 are aligned at intervals around the circumference of the flange portion 123.

[0013] A frame mesh 18 is placed on the flange portion 123 of the frame 12 from the outside of the frame 12. The frame mesh 18 is formed in a ring shape corresponding to the flange portion 123. As a result, the frame mesh 18 covers the multiple through holes 124 of the flange portion 123 from the outside of the frame 12. The frame mesh 18 is made of a mesh material or a woven fabric such as plain weave, and does not prevent air from entering and exiting the inside of the frame 12 through the multiple through holes 124 of the flange portion 123.

[0014] 2 has a cutout portion 181 formed by cutting out a part of the frame mesh 18 in the circumferential direction. A connection terminal 131 to be electrically connected to the voice coil 13 is disposed in the cutout portion 181 of the frame mesh 18.

[0015] Diaphragm 11 is attached to frame 12 so as to divide the internal space of cylindrical frame 12 in the axial direction of frame 12. Specifically, diaphragm 11 is attached to large diameter portion 121 of frame 12. In the following description, the surface of diaphragm 11 facing small diameter portion 122 of frame 12 will be referred to as back surface 11b, and the surface of diaphragm 11 facing the opposite side to back surface 11b will be referred to as front surface 11a. The rear surface 11b of the diaphragm 11 faces the space inside the small diameter portion 122 of the frame 12, as well as the flange portion 123 and the plurality of through holes 124 formed therein.

[0016] Protector 17 is attached to frame 12 so as to be positioned on the front surface 11a side of diaphragm 11. Protector 17 protects the front surface 11a side of diaphragm 11 so as not to interfere with the vibration of diaphragm 11. Protector 17 has a plurality of openings 171 formed therein. This allows air to flow in and out of the space between protector 17 and front surface 11a of diaphragm 11 through the plurality of openings 171 in protector 17 without interfering with the flow of air.

[0017] The voice coil 13 is attached to a cylindrical bobbin 19 provided on the back surface 11b of the diaphragm 11. The voice coil 13 is disposed inside the small diameter portion 122 of the frame 12.

[0018] The pole piece 14, magnet 15, and pot yoke 16 are provided on the back surface 11b side of the diaphragm 11, and constitute a magnetic path forming portion that forms a magnetic field inside and outside the voice coil 13. The pole piece 14, magnet 15, and pot yoke 16 are all arranged inside the small diameter portion 122 of the frame 12. The pot yoke 16 is arranged in the opening on the small diameter portion 122 side of the frame 12. Therefore, the back surface 16b of the pot yoke 16, which faces the same side as the back surface 11b of the diaphragm 11, constitutes part of the outer surface of the driver unit main body 1 together with the outer surface of the frame 12.

[0019] The pole piece 14, the magnet 15, and the pot yoke 16 are formed with through holes 141, 151, and 161 for opening the space on the back surface 11b side of the diaphragm 11 to the outside of the driver unit main body 1. The through holes 141, 151, and 161 of the pole piece 14, the magnet 15, and the pot yoke 16 are configured as ventilation holes 10 of the driver unit main body 1 formed on the back surface 11b side of the diaphragm 11.

[0020] In the driver unit main body 1 configured as described above, the diaphragm 11 vibrates in response to an electrical signal input from the outside to the voice coil 13. As a result, sound is emitted from the front surface 11a of the diaphragm 11 to the outside of the driver unit main body 1 through multiple openings 171 in the protector 17. The vibration of the diaphragm 11 also propagates from the back surface 11b of the diaphragm 11 to the outside of the driver unit main body 1 through the through-holes 141, 151, 161 (air vents 10 in the driver unit main body 1) in the pole piece 14, magnet 15, and pot yoke 16, and multiple through-holes 124 in the flange portion 123 of the frame 12.

[0021] Ventilation member 2 covers the ventilation holes 10 of the driver unit main body 1 from the outside of the driver unit main body 1. Ventilation member 2 is made of a mesh material or a woven fabric such as plain weave, and does not prevent air from entering and exiting the inside of frame 12 through ventilation holes 10. 1, 3, and 4, the ventilation member 2 has an annular attachment portion 21 that is attached to the peripheral region of the outer surface of the driver unit main body 1 where the ventilation holes 10 open. The attachment portion 21 is the portion of the ventilation member 2 that overlaps with a fixing member 4, which will be described later. The ventilation member 2 also has a covering portion 22 that is located inside the attachment portion 21 and covers the ventilation holes 10 of the driver unit main body 1.

[0022] 3 is formed in a circular shape when viewed in a plan view from its thickness direction, but is not limited to this and may be, for example, rectangular, etc. However, it is more preferable that the shape of the ventilation member 2 in a plan view be the same as the shape of the ventilation hole 10 of the driver unit main body 1 in a plan view.

[0023] The reinforcing member 3 shown in Figures 3 and 4 reinforces the above-mentioned ventilation member 2. The reinforcing member 3 has the function of suppressing vibration of the ventilation member 2. Specifically, the reinforcing member 3 suppresses vibration of the ventilation member 2 to control the vibration characteristics of the ventilation member 2. The reinforcing member 3 is made of a material that is less elastic than the ventilation member 2, such as PET (polyethylene terephthalate).

[0024] As shown in FIG. 3 , the reinforcing member 3 has a plurality of strip-shaped portions 31 extending in different directions from the center O of the ventilation member 2 to the attachment portion 21 when viewed from the direction in which the ventilation hole 10 of the driver unit main body 1 and the ventilation member 2 overlap (the thickness direction of the ventilation member 2). Each of the plurality of strip-shaped portions 31 overlaps the covering portion 22 of the ventilation member 2. In this embodiment, the plurality of strip-shaped portions 31 are arranged at equal intervals in the circumferential direction of the attachment portion 21 of the ventilation member 2, with the center O of the ventilation member 2 as the axis. The width dimension (thickness) of the plurality of strip-shaped portions 31 as viewed from the thickness direction of the ventilation member 2 is equal to one another. It is more preferable that the width dimension of the strip-shaped portions 31 is small. Note that the width dimension of the plurality of strip-shaped portions 31 may differ, for example, among the plurality of strip-shaped portions 31. While the number of strip-shaped portions 31 in FIG. 3 is three, it may be, for example, two or four or more. In this embodiment, the reinforcing member 3 is provided on the opposing surface 2a of the ventilation member 2 that faces the driver unit main body 1 side.

[0025] The fixing member 4 is provided on the opposing surface 2a of the ventilation member 2. The fixing member 4 has the function of fixing the attachment portion 21 of the ventilation member 2 to the aforementioned peripheral region. That is, the fixing member 4 is formed in a ring shape corresponding to the attachment portion 21. The fixing member 4 may be, for example, an adhesive. The fixing member 4 may also be, for example, a double-sided tape having a PET base material. When the fixing member 4 is a double-sided tape, the fixing member 4 can be formed in advance to have the same shape as the attachment portion 21, thereby making it possible to easily attach the attachment portion 21 to the peripheral region. In this embodiment, the reinforcing member 3 is integrally formed with the fixing member 4. Therefore, the reinforcing member 3 and the fixing member 4 are made of the same material.

[0026] In the driver unit 100 of this embodiment, when the ventilation member 2 is fixed to the outer surface of the driver unit main body 1 (the back surface 16b of the pot yoke 16) by the fixing member 4, the portion of the mounting portion 21 of the ventilation member 2 that is not fixed by the fixing member 4 radially inside the annular fixing member 4 is extremely small or nonexistent.

[0027] Next, the ability of the driver unit 100 of this embodiment to suppress THD caused by the ventilation member 2 will be described with reference to Fig. 5. The graph in Fig. 5 shows the frequency characteristics of the driver units of an example and a comparative example. The driver unit of the example is the driver unit 100 of this embodiment. The driver unit of the comparative example has a configuration in which the reinforcing member 3 is not provided on the ventilation member 2 in the driver unit 100 of this embodiment.

[0028] In the driver unit of the comparative example, THD tends to decrease as the frequency increases in the low frequency band, but a peak where THD increases appears in the intermediate frequency band. This THD peak is caused by the ventilation member 2. Specific factors that cause THD to increase due to the ventilation member 2 are the sound generated by the ventilation member 2, which vibrates greatly, and the sound of the ventilation member 2 vibrating greatly and striking the driver unit main body 1 (pot yoke 16).

[0029] In contrast, in the driver unit 100 of the embodiment, the THD continuously decreases as the frequency increases from the low frequency band to the intermediate frequency band, that is, no THD peak appears in the intermediate frequency band. From the above, it has become clear that the THD caused by the ventilation member 2 can be suppressed by the reinforcing member 3.

[0030] As described above, in the driver unit 100 of this embodiment, the reinforcing member 3 makes the ventilation member 2 attached to the driver unit main body 1 less likely to vibrate. Specifically, the multiple strip-shaped portions 31 of the reinforcing member 3 improve the rigidity of the ventilation member 2, making the ventilation member 2 less likely to vibrate. As a result, even if vibrations of the diaphragm 11 are transmitted to the ventilation member 2 through the ventilation holes 10 of the driver unit main body 1, it is possible to effectively prevent the ventilation member 2 from vibrating significantly due to the vibrations and generating sound from the ventilation member 2. Therefore, THD caused by the ventilation member 2 can be suppressed.

[0031] Furthermore, in driver unit 100 of this embodiment, reinforcing member 3 is formed integrally with fixing member 4, which is used to fix mounting portion 21 of ventilation member 2 to the outer surface of driver unit main body 1. Therefore, THD can be suppressed without increasing the number of components of driver unit 100.

[0032] Furthermore, in driver unit 100 of this embodiment, the ventilation area of ​​ventilation member 2 through which air passes is divided into multiple areas by multiple strip-shaped portions 31. The multiple strip-shaped portions 31 are arranged at equal intervals in the circumferential direction of mounting portion 21, so that the multiple ventilation areas can be made equal in size and shape. This makes the vibration characteristics of the multiple ventilation areas equal, thereby further suppressing THD.

[0033] Furthermore, in driver unit 100 of this embodiment, when ventilation member 2 is fixed to the outer surface of driver unit main body 1 by fixing member 4, the portion of mounting portion 21 of ventilation member 2 that is not fixed by fixing member 4 is extremely small or nonexistent radially inside of annular fixing member 4. Therefore, when ventilation member 2 vibrates relative to driver unit main body 1, not only the portion of mounting portion 21 of ventilation member 2 that is fixed by fixing member 4, but also the portion of mounting portion 21 of ventilation member 2 that is not fixed hits the outer surface of driver unit main body 1, suppressing or preventing sound from being generated. This makes it possible to effectively suppress THD.

[0034] Although the present invention has been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

[0035] In the driver unit 100 of the above embodiment, for example, the plurality of through holes 124 formed in the flange portion 123 of the frame 12 may be configured as ventilation holes in the driver unit main body 1 formed on the rear surface 11b side of the diaphragm 11. The frame mesh 18 may also function as a ventilation member in the present invention. For this reason, the frame mesh 18 may be provided with the reinforcing member 3 and fixing member 4 similar to those in the above embodiment. This makes it possible to suppress THD caused by the frame mesh 18. Furthermore, in driver unit 100 of the above embodiment, it is sufficient to form either through holes 141, 151, 161 in pole piece 14, magnet 15, and pot yoke 16, or multiple through holes 124 formed in flange portion 123 of frame 12, which function as ventilation holes in driver unit main body 1. Either one of the through holes allows part of the space on the back surface 11b side of diaphragm 11 to be opened to the outside of driver unit main body 1.

[0036] In the present invention, the multiple strip-shaped portions 31 of the reinforcing member 3 do not have to be formed integrally with the fixing member 4, as shown in FIGS. 6 and 7, for example. Furthermore, the reinforcing member 3 may be provided on the opposite surface 2b of the ventilation member 2 that faces the opposite side to the opposing surface 2a, as shown in FIGS. 6 and 7. In the configuration example of FIGS. 6 and 7, the multiple strip-shaped portions 31 provided on the opposite surface 2b of the ventilation member 2 extend in different directions from the center O of the ventilation member 2 to the mounting portion 21 of the ventilation member 2, and overlap with the fixing member 4 in the thickness direction of the ventilation member 2. This allows the ventilation member 2 to be attached to the driver unit 100 without any gaps, even if the reinforcing member 3 and the fixing member 4 are separate parts.

[0037] In the present invention, the multiple strip-shaped portions 31 of the reinforcing member 3 may be arranged at unequal intervals in the circumferential direction of the attachment portion 21 of the ventilation member 2, for example. Even with this configuration, the reinforcing member 3 improves the rigidity of the ventilation member 2, thereby making it possible to suppress THD caused by the ventilation member 2. [Explanation of symbols]

[0038] 1...driver unit main body, 2...ventilation member, 2a...opposing surface, 3...reinforcing member, 4...fixing member, 10...ventilation hole, 11...diaphragm, 11b...rear surface of diaphragm 11, 16b...rear surface of pot yoke 16 (outer surface of driver unit main body 1), 21...mounting portion, 31...band-shaped portion, 100...driver unit, O...center of ventilation member 2

Claims

1. a driver unit body having a diaphragm and a vent hole formed on the rear surface side of the diaphragm; a ventilation member that covers the ventilation hole from the outside of the driver unit main body; a reinforcing member that reinforces the ventilation member, the ventilation member has an annular attachment portion that is attached to a peripheral area of ​​the outer surface of the driver unit main body where the ventilation hole opens, The reinforcing member has a plurality of strip-shaped portions that extend in different directions from the center of the ventilation member to the mounting portion when viewed from the direction in which the ventilation hole and the ventilation member overlap.

2. a fixing member provided on a surface of the ventilation member facing the driver unit main body, for fixing the attachment portion to the peripheral region; The driver unit according to claim 1 , wherein the reinforcing member is provided on the opposing surface and is integrally formed with the fixing member.

3. 3. The driver unit according to claim 1, wherein the plurality of strip-shaped portions are arranged at equal intervals in the circumferential direction of the attachment portion of the ventilation member, with the center of the ventilation member as an axis.

4. a driver unit body having a diaphragm and a vent hole formed on the rear surface side of the diaphragm; a ventilation member that covers the ventilation hole from the outside of the driver unit main body; a reinforcing member that reinforces the ventilation member, the ventilation member has an annular attachment portion that is attached to a peripheral area of ​​the outer surface of the driver unit main body where the ventilation hole opens, The reinforcing member is a driver unit that suppresses vibration of the ventilation member.

Images