JP6583226B2 - headphone - Google Patents

Description

  The present invention relates to a headphone and an earphone that are attached to a user's ear and reproduce sound, and more particularly, to a headphone including a housing that defines a back chamber on the back side of a speaker unit.

  The headphones include a speaker unit, a housing surrounding the back side of the speaker unit, and an ear contact portion provided on the front side of the speaker unit. The headphones here include not only those in which a pair of left and right housings are connected by a headband, but also earphone types that directly support the housing on the user's ears, and so-called headsets in which the housing is equipped with a microphone device. It is out.

  Such headphones are known in which a space in the housing is communicated with the outside by opening a hole in the housing. The following Patent Document 1 discloses an acoustic transducer for the purpose of improving the response in the low frequency range by changing the acoustic equivalent circuit on the back side of the acoustic transducer without changing the structure of the acoustic transducer (speaker unit). The housing (housing) to which is attached is provided with a duct portion for emitting sound emitted from the rear surface of the acoustic transducer to the outside.

  In addition, in headphones, when a hole is opened in the housing surrounding the back side of the speaker unit, and the space inside the housing communicates with the outside, external noise easily enters the space inside the housing, and a diaphragm or acoustic filter The noise that has passed through the structural member of the speaker unit having air permeability and the like and entered the housing reaches the listener's ear. In this case, since the listener listens to external noise together with the sound emitted from the speaker unit, there arises a problem that the reproduced sound of the speaker unit cannot be heard clearly.

  In the headphones disclosed in Patent Document 2 below, as an example of dealing with such a problem, when the space in the housing surrounding the back side of the speaker unit is communicated to the outside, the listener can hear noise from the outside. The housing is provided with an internal space and an air chamber different from the internal space for the purpose of being able to be made difficult, etc., and the space inside the ear contact portion communicates with the listener's ear and the air chamber and the interior. The space communicates with the outside through a space, the air chamber is formed by an outer peripheral wall portion and an inner peripheral wall portion facing each other of the housing, and a first hole portion communicating with the outside is formed in the outer peripheral wall portion, A second hole communicating with the internal space of the housing is formed in the peripheral wall, and the first hole and the second hole are located at different positions along the outer periphery of the housing so as not to face each other. It discloses a headphone characterized.

  As described above, in a headphone in which a space in the housing is communicated with the outside by opening a hole in the housing, the configuration of the housing has a great influence on the reproduction sound quality of the headphone. When the speaker unit is relatively large, the housing is also relatively large, so the housing that forms the air chamber and the internal space is large, and a standing wave that is an acoustic resonance in the air chamber is generated, or Problems such as vibration of members constituting the housing are likely to occur. Therefore, in the case of including a large air chamber and a housing that constitutes the internal space, there is a problem that it is difficult to configure headphones having excellent reproduction sound quality and stable quality.

Japanese Unexamined Patent Publication No. 7-170591 Japanese Patent No. 5902202

  The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention relates to a headphone including a housing defining a back chamber on the back side of a speaker unit, and a large internal space and an air chamber. Even in the case of including a housing to be configured, it is an object to provide headphones having excellent reproduction sound quality and stable quality.

A headphone of the present invention includes a speaker unit, an internal space provided on the back side of the sound emission side of the accommodated speaker unit, and a housing defining an inner wall portion separating an air chamber provided separately from the internal space , The distance between the wall surface part defining the internal space and the speaker unit is the shortest closest to the center of the back surface of the speaker unit, and has a convex part that increases from the vicinity of the center to the outer diameter direction and becomes longer . A first housing member, and a second housing member that is connected to the first housing member and defines an internal space. The inner wall includes a first hole portion that communicates the external space with the internal space. Forming a second hole portion that communicates the air chamber and the internal space in the portion, and the first hole portion communicates the outside and the internal space via the air chamber. The

  Preferably, the headphone of the present invention is formed such that the wall surface portion including the convex portion of the housing is thickest in the vicinity of the center of the back surface of the speaker unit, and becomes thinner as it moves from the vicinity of the center to the outer diameter direction. ing.

  The operation of the present invention will be described below.

  The headphones of the present invention include a speaker unit and a housing that defines an internal space provided on the back side of the accommodated speaker unit on the acoustic emission side. The internal space of the housing is defined by being surrounded by the wall surface of the housing, and acts as an acoustic capacity in the acoustic circuit on the back side of the diaphragm of the speaker unit. Therefore, the housing covering the back side of the speaker unit increases the volume of the internal space if the distance between the wall surface part defining the internal space and the speaker unit increases.

  In the headphone housing of the present invention, the distance between the wall surface part defining the internal space and the speaker unit is shortened closest to the vicinity of the center of the back surface of the speaker unit, and becomes longer as the distance from the center shifts to the outer diameter direction. Has a convex part. This separation distance can be defined as, for example, a cross-sectional distance between the rear end portion of the magnetic circuit of the speaker unit and the wall surface portion of the housing. Therefore, the convex portion protrudes toward the speaker unit so as to narrow the internal space at a substantially central portion of the internal space. As a result, the volume of the internal space of the housing can be made relatively small, and the occurrence of standing waves that are acoustic resonances in the internal space can be suppressed. In addition, since the convex portion diffuses the sound wave radiated to the back side of the speaker unit, it is possible to suppress the distribution of the change in the sound pressure level difference in the internal space, and headphones having excellent reproduction sound quality can be suppressed. Can be realized.

  Here, it is preferable that the wall surface portion including the convex portion of the housing is formed so that the material thickness is thickest in the vicinity of the center of the back surface of the speaker unit, and becomes thinner as it moves from the vicinity of the center in the outer diameter direction. The use of a housing member that can be die-casted to the maximum thickness near the center of the back of the speaker unit where the convex part is formed will improve the rigidity of the wall surface, so vibration from the speaker unit Even when the vibration is transmitted, the vibration of the housing can be suppressed. As a result, headphones with excellent reproduction sound quality and stable quality can be configured.

  The headphone housing may include a first housing member having a convex portion and a second housing member to which a speaker unit is attached and connected to the first housing member to define an internal space. If the first housing member and the second housing member are configured as separate members, there is an advantage that the housing can be configured using the same or different suitable materials. Further, if the first housing member is provided with a first hole portion that allows communication between the outside and the internal space, the space in the housing surrounding the back side of the speaker unit can be communicated with the outside.

  Further, the headphone housing has a first hole and a second housing member that define an inner wall that separates an air chamber that is provided separately from the inner space, and a second hole that communicates the air chamber and the inner space with the inner wall. A portion may be formed, and the first hole portion may communicate the outside and the internal space via the air chamber. Since the housing communicates with the outside through the air chamber and the internal space, it is possible to make it difficult for the listener to hear noise from the outside. Moreover, even if it has the housing which comprises a large interior space and an air chamber, the headphones which are excellent in reproduction | regeneration sound quality can be comprised.

  The headphone of the present invention can provide a headphone that is excellent in reproduction sound quality and stable in quality even when it includes a housing that forms a large internal space and an air chamber.

1 is an external view of a headphone according to an embodiment of the present invention. It is explanatory drawing which showed the specific structure of the headphone unit which concerns on one Embodiment of this invention. It is explanatory drawing which showed the specific structure of the other headphone unit which concerns on one Embodiment of this invention. It is a graph which shows the sound pressure distribution in the internal space of the housing of the headphones which concern on one Embodiment of this invention.

  Hereinafter, headphones according to preferred embodiments of the present invention will be described, but the present invention is not limited to these embodiments.

  FIG. 1 is a diagram for explaining a headphone 1 according to a preferred embodiment of the present invention. Specifically, FIG. 1 is a perspective view showing the appearance of the headphones 1. The form of the headphones 1 is not limited to the case of the present embodiment. The illustration and description of the configuration of other headphones 1 unnecessary for the description of the present invention are omitted.

  The headphone 1 of the present embodiment includes left and right headphone units 1A and 1B, and a headband 1C that connects these headphone units 1A and 1B. The headphone units 1 </ b> A and 1 </ b> B are each provided with a housing 2 and an ear contact portion 3 that accommodate the speaker unit. The headband 1C is connected to a connecting portion with the hanger 1D, and the hangers 1D and 1D are connected to the housings 2 and 2, respectively.

  The headphone 1 is provided with a plurality of holes 2 a (to be described later) (not shown) on the side of the housing 2, and the inner space of the housing 2 is connected to the outside of the housing 2 outside the ear contact portion 3 by the holes 2 a. Communicate. The headphones 1 can adjust the compliance (acoustic capacity) due to the internal space of the housing 2 by the hole 2a, and can adjust the frequency characteristics, particularly the frequency characteristics in the low frequency range, by adjusting the compliance.

  2 and 3 are explanatory views showing a specific structure of the housing 2 including the internal space 2S and the air chamber 30 in one headphone unit 1A of the headphone 1 according to the embodiment of the present invention. FIG. 2 is a cross-sectional view showing an internal structure when the housing member 21 is used in the housing 2. FIG. 3 is a cross-sectional view showing a specific example when another housing member 21 </ b> D is used in the housing 2. These differ in the specific configurations of the convex portions 20 and 20D described later.

  As described above, the headphone units 1 </ b> A and 1 </ b> B of the headphone 1 include the speaker unit 10, the housing 2 surrounding at least the back side of the speaker unit 10, and the ear contact portion 3 provided on the front side of the speaker unit 10. . Any of the housings 2 shown in FIGS. 2 and 3 can be employed for the headphone units 1A and 1B. 2 and 3, the central axis O-O ′ of the substantially circular headphone unit 1 </ b> A substantially coincides with the central axis of the substantially circular speaker unit 10.

  The speaker unit 10 includes a diaphragm 11, a voice coil connected to the diaphragm 11, a magnetic circuit 13 having a magnetic gap in which the voice coil is disposed, and a frame that supports an outer peripheral portion of the diaphragm 11 via an edge. 15 is provided. The magnetic circuit 13 is supported by the frame 15 and further connected to the connecting member 22. The magnetic circuit 13 includes a plate, a magnet, and a yoke, and the above-described magnetic gap is formed between the plate and the yoke. The configuration of the speaker unit 10 is not limited to this, and various known modes such as forming a magnetic gap between the magnet and the yoke can be adopted.

  The housing 2 includes a connecting member 22 to which the speaker unit 10 is connected and a casing member 21 or 21D surrounding the back side of the speaker unit 10. The casing member 21 or 21 </ b> D includes a wall surface portion 21 </ b> A that defines the internal space 2 </ b> S on the back side of the speaker unit 10, an outer peripheral cylindrical portion 21 </ b> B, and a surface portion 21 </ b> C. Furthermore, each wall surface portion 21A includes a convex portion 20 or a convex portion 20D. Therefore, the internal space 2S is also defined by the convex portion 20 or the convex portion 20D.

  In the housing 2 of FIG. 2, the convex portion 20 is formed as a member different from the housing member 21 and is connected to the vicinity of the center of the wall surface portion 21 </ b> A. The convex portion 20 is a member having a mountain-like shape in which the peak of a single peak is one and the base is widened and lowered. Therefore, in the internal space 2S, the separation distance d between the wall surface portion 21A including the convex portion 20 defining the internal space 2S and the speaker unit 10 is shortened most closely in the vicinity of the center of the back surface of the speaker unit 10, It becomes longer as it moves from the vicinity of the center to the outer diameter direction indicated by the R direction. The convex portion 20 protrudes toward the speaker unit 10 so as to narrow the internal space 2S at a substantially central portion of the internal space 2S.

  On the other hand, in the housing 2 of FIG. 3, the wall surface portion 21A is formed such that the material thickness t is thickest in the vicinity of the center of the back surface of the speaker unit 10 so that the convex portion 20D is formed in the vicinity of the center. Has been. Accordingly, in the internal space 2S, the separation distance d between the speaker unit 10 and the wall surface portion 21A including the convex portion 20D that similarly defines the internal space 2S and the center of the back surface of the speaker unit 10 are shortest and shortest. It becomes longer as it moves from the center vicinity to the outer diameter direction indicated by the R direction. The convex portion 20D protrudes toward the speaker unit 10 so as to narrow the internal space 2S at a substantially central portion of the internal space 2S.

  A hanger 1D is rotatably attached to the outer peripheral cylindrical portion 21B of the housing member 21 or 21D. The connecting member 22 connected to the housing member 21 or 21D includes a support portion 22A that supports the speaker unit 10. The support portion 22A protrudes inside the housing 2 and supports the frame 15 of the speaker unit 10. The ear contact portion 3 is attached to the connecting member 22.

  The ear contact portion 3 includes an annular elastic member and a covering member that covers the elastic member. The ear contact portion 3 is attached to the connecting member 22 of the housing 2 on the acoustic emission side of the speaker unit 10. The ear contact portion 3 is in contact with the listener's ear, thereby dividing the outside of the housing 2 into a space inside the ear contact portion 3 (external space S1) and an outside S2 outside the ear contact portion 3. The outer space S1 of the housing 2 inside the ear contact portion 3 is a space communicating with the listener's ear. The outside S2 of the housing 2 outside the ear contact portion 3 is separated from the space in the ear by the ear contact portion 3.

  In the headphone unit 1 </ b> A (1 </ b> B), the internal space 2 </ b> S of the housing 2 communicates with the external space S <b> 1 of the housing 2 inside the ear contact portion 3. Specifically, the internal space 2S includes a housing member 21 or 21D constituting the housing 2, a convex portion 20 or a convex portion 20D, a connecting member 22 to which the speaker unit 10 is connected, and a hole formation described later. It is comprised including the member 23. FIG. The internal space 2 </ b> S of the housing 2 communicates with the external space S <b> 1 of the housing 2 inside the ear contact part 3 through an opening 22 </ b> D provided in the connecting member 22 of the housing 2. Further, when the speaker unit 10 has a constituent member such as a diaphragm 11 having air permeability, the internal space 2S of the housing 2 is located inside the ear contact portion 3 through the air-permeable constituent member. It communicates with the external space S1. The opening 22D may be covered with a breathable member such as a nonwoven fabric.

  The housing 2 is provided with an air chamber 30 separately from the internal space 2S of the housing 2. The air chamber 30 may be provided inside the housing 2 or outside the housing. For example, the outer peripheral side surface of the housing 2 on the outer side of the housing 2, the inner peripheral side surface of the housing 2 on the inner space side of the housing 2, or the case where an air chamber is provided inside the member constituting the housing 2, etc. . The internal space 2 </ b> S of the housing 2 communicates with the external S <b> 2 of the housing 2 outside the ear contact portion 3 via the air chamber 30. The air chamber 30 in this embodiment is formed by the constituent members of the housing 2.

  That is, the air chamber 30 includes a housing member 21 or 21D that constitutes the housing 2, a connecting member 22 to which the speaker unit 10 is connected, and a hole forming member 23 to be described later. The housing 2 includes the air chamber 30 described above as a first air chamber and the internal space 2S of the housing 2 as a second air chamber. The casing member 21 or 21D and the connecting member 22 define an inner wall portion 32 that separates the internal space 2S and the air chamber 30 from each other.

  As a result, the housing 2 includes a double wall structure in the wall portion (side portion), and includes an outer wall portion 31 and an inner wall portion 32. The air chamber (first air chamber) 30 is disposed between the outer wall portion 31 facing the outside S2 of the housing 2 outside the ear contact portion 3 and the inner wall portion 32 facing the inner space 2S of the housing 2. ing. The outer wall portion 31 includes a first hole portion 2a and is provided in the outer peripheral cylindrical portion 21B that is the outer peripheral side surface of the housing 2 in the illustrated example. The inner wall portion 32 includes a hole forming member 23 in which the second hole portion 2b is formed.

  The hole forming member 23 is a substantially cubic member whose one side is longer than the thickness dimension t2 of the inner wall portion 32, and is sandwiched between the casing member 21 or 21D and the connecting member 22 and fixed to the inner wall portion. The In this embodiment, the hole forming member 23 is a block-shaped member having predetermined width dimensions, depth dimensions, and height dimensions longer than the thickness dimension t2, and communicates the internal space 2S and the air chamber 30 in the depth direction. A second hole 2b is formed. Therefore, the second hole portion 2b can form a through-hole having a total length longer than the dimension t2 only in the inner wall portion 32.

  If the length of the second hole 2b of the hole forming member 23 can be increased, the compliance by the internal space 2S of the housing 2 and the air quality 30 can be adjusted, and the frequency characteristics, particularly the low frequency range, can be adjusted by adjusting the compliance. Can be adjusted. In the hole forming member 23 of the present embodiment, three second hole portions 2b are formed. Since the hole forming member 23 is a substantially cubic member, compliance can be adjusted by providing a plurality of second hole portions 2b and adjusting the number thereof.

  The housing member 21 or 21D of the housing 2 and the connecting member 22 are provided with a notch for fitting the hole forming member 23, and the hole forming member 23 is also provided with a groove for fitting with the notch. . The hole forming member 23 can be firmly attached to the inner wall portion 32, and it can be avoided that the opening size and length of the second hole portion 2b are difficult to stabilize.

  In the illustrated example, the housing 2 is configured by connecting a constituent member of the connecting member 22 and a constituent member of the housing member 21 or 21D. The air chamber (first air chamber) 30 is provided in the vicinity of the connection position between the connecting member 22 and the casing member 21 or 21D. Specifically, it is provided at the connection position of the connecting member 22 and the casing member 21 or 21D in the radial direction of the housing 2. Further, the air chamber 30 may be configured by a part of the connecting member 22 and a part of the casing member 21 or 21D, or may be configured by the entire connecting member 22 and the entire casing member 21 or 21D. Absent.

  The connecting member 22 includes a support portion 22 </ b> A that supports the speaker unit 10 on the housing 2, and a protection portion 22 </ b> B that faces the acoustic radiation surface of the speaker unit 10. An opening 22C through which the diaphragm 11 of the speaker unit 10 is exposed is defined in the protective portion 22B. Each of the support portion 22A and the protection portion 22B has an opening 22D. The opening 22D allows the internal space 2S and the external space S1 of the housing 2 to communicate with each other.

  In the illustrated example, a part of the air chamber 30 is formed in the connecting member 22. The connecting member 22 has an inner wall portion 32 provided on the inner space 2S side. The inner wall portion 32 on the housing 2 side is provided with a notch portion in which the hole forming member 23 is sandwiched between the housing member 21 or 21D and the connecting member 22 and fixed to the inner wall portion 32. A part of the air chamber 30 is formed along the outer periphery of the connecting member 22. In the illustrated example, part of the air chamber 30 is formed in two places on the connecting member 22.

  The support portion 22 </ b> A of the connecting member 22 is provided between the outer peripheral portion of the speaker unit 10 and the inner wall portion 32 while supporting the speaker unit 10. Further, the support portion 22 </ b> A of the connecting member 22 is disposed on the side facing the ear contact portion 3. A gap 22D is provided between the ear contact portion 3 and the support portion 22A. The internal space 2S (second air chamber) of the housing 2 communicates with the external space S1 of the housing 2 inside the ear contact portion 3 through the gap 22D and the opening 22D of the support portion 22A. By providing such a gap 22 </ b> D, even if the support portion 22 </ b> A of the connecting member 22 is covered with the ear contact portion 3, the second air chamber (internal space 2 </ b> S) and the housing 2 inside the ear contact portion 3 can be provided. The external space S1 can be communicated with and the acoustic characteristics in the low sound range can be improved.

  On the other hand, the air chamber 30 (first air chamber) is located in the housing 2 with respect to the opening 22C of the support portion 22A in the direction (outer diameter direction R) from the internal space 2S of the housing 2 to the outside S2 of the housing 2. It is provided outside. By providing the air chamber 30 on the outside of the housing 2 with respect to the speaker unit 10, the space on the housing 2 side can be saved, and the speaker unit 10 can be made as large as possible.

  In the headphones 1, when the air chamber 30 is a first air chamber, a second air chamber (internal space 2 </ b> S) is provided between the inner wall portion 32 and the speaker unit 10. The second air chamber (internal space 2S) communicates with the outside S1 of the housing 2 outside the ear contact portion 3 via the first air chamber (air chamber 30). Further, the second air chamber (internal space 2S) communicates with the external space S1 of the housing 2 inside the ear contact portion 3 through the opening 22D of the connecting member 22 or the breathable component of the speaker unit 10. is doing.

  In the illustrated embodiment, the air chamber 30 extends along the outer peripheral portion of the housing 2. The position of the first hole 2a that communicates from the air chamber 30 to the outside S2 of the housing 2 outside the ear contact portion 3, and the air chamber 30 communicates with the interior space 2S (second air chamber) of the housing 2. The positions of the first hole 2a and the second hole 2b are preferably different along the outer peripheral portion of the housing 2 so that the position of the second hole 2b does not oppose. According to this, the noise that enters the housing 2 from the outside S2 of the housing 2 outside the ear contact portion 3 is reflected on the wall portion of the air chamber 30, and the propagation path of the noise as a sound wave is refracted. That is, noise can be prevented from entering the internal space 2S (second air chamber) of the housing 2 due to reflection in the air chamber 30 or the like.

  The headphone 1 having such a form example communicates the internal space 2 </ b> S of the housing 2 with the external S <b> 2 of the housing 2 outside the ear contact portion 3, so that the space on the housing 2 side with respect to the speaker unit 10 is large. Can be substantially enlarged, and the low-frequency characteristics of the speaker unit 10 can be improved. At this time, noise enters the internal space of the housing 2 from the outside S2 of the housing 2 outside the ear contact portion 3, but the outside S2 of the housing 2 and the housing outside the ear contact portion 3 on the noise propagation path. By providing the first air chamber (air chamber 30) between the two inner spaces, noise that propagates to the outer space S1 of the housing 2 inside the ear contact portion 3 can be reduced. Thereby, the sound insulation of the headphones 1 can be improved.

  In the headphone 1, the housing 2 may be formed with a first hole 2 a by a hole forming member (not shown) that is sandwiched and fixed between the housing member 21 or 21 </ b> D and the connecting member 22. By providing this hole forming member on the outer wall 31 that separates the outside of the housing member 21 or 21D of the housing 2 from the air chamber, the first hole 2a can be formed. The hole forming material portion can be a substantially cubic member whose one side is longer than the thickness dimension t1 of the outer wall portion 31. The hole forming material portion is preferably configured to be sandwiched between the casing member 21 or 21D and the connecting member 22 and fixed to the outer wall portion 31. The casing member 21 or 21 </ b> D and the connecting member 22 may be provided with a notch portion into which the hole forming portion is fitted, and the hole forming member 23 may be provided with a groove portion to be fitted with the notch portion. The hole forming member is formed with a first hole portion 2a that is a through hole having a longer overall length than the dimension t1 of the outer wall portion 31 that allows the external space S2 and the air chamber 30 to communicate with each other.

  As described above, in the headphone 1, when the speaker unit 10 has a large diameter and is relatively large so as to provide a large diaphragm 11 and a magnetic circuit 13 in pursuit of reproduction sound quality, the housing 2 is also relatively large. . When the air chamber 2S and the internal space 30 become large, a standing wave that is acoustic resonance in the air chamber 2S is generated, or the casing member 21 or 21D constituting the housing 2 vibrates. It tends to occur. In the headphone 1 of the present embodiment, since the internal space 2S is defined by the convex portion 20 or the convex portion 20D, the occurrence of standing waves in the air chamber 2S can be suppressed.

  FIG. 4 is a graph showing the sound pressure distribution in the internal space 2S of the housing 2 of the headphones 1. Specifically, in the case of a frequency where a standing wave is generated in the internal space 2S of the housing 2 (7700 Hz in the present embodiment), it is made to correspond to the gray shading of the right vertical axis. The distribution of the sound pressure level at each position is illustrated. In the graph of FIG. 4, only the axisymmetric quarter portion of the internal space 2S is shown and the other portions are omitted, but the position of the antinode of the standing wave having a high sound pressure level in the internal space 2S and the sound It can be seen that the positions of the nodes of the standing wave having a low pressure level are distributed. In FIG. 4, the illustration of the wall surface portion 21A, the inner wall portion 32, the connecting member 22, and the speaker unit 10 that define the internal space 2S is omitted. Double-ended arrows along the right vertical axis indicate the range of sound pressure level values shown in the graph.

  FIG. 4A shows the case of the present embodiment in which the internal space 2S is defined by the wall surface portion 21A including the convex portion 20D, and FIG. 4B shows the flat wall surface not including the convex portion 20D. This is a case of a comparative example in which the internal space 2S is defined by the portion 21A. In the case of the present embodiment including the convex portion 20D, the standing wave in the internal space 2S is suppressed, and the distribution of the sound pressure level value that varies depending on the position is as low as about 35 dB to about 70 dB. It is a value. On the other hand, in the case of the comparative example that does not include the convex portion 20D, the standing wave in the internal space 2S is not suppressed, and the distribution of the sound pressure level value that varies depending on the position is in the range of about 45 dB to about 90 dB. The value is very high.

  In the case of the present embodiment, the inner space 2S is defined by the wall surface portion 21A including the convex portion 20D. Therefore, the separation distance d between the wall surface portion 21A including the convex portion 20D and the speaker unit 10 is the speaker unit 10. Near the center of the rear surface of the rear surface, the distance is shortened most closely, and the distance from the vicinity of the center to the outer diameter direction R increases. Therefore, since the convex portion 20D protrudes toward the speaker unit 10 so as to narrow the internal space 2S at the substantially central portion of the internal space 2S, generation of standing waves that are acoustic resonance in the internal space 2S is prevented. Can be suppressed. Further, since the convex portion 20D diffuses the sound wave radiated to the back side of the speaker unit 10, the distribution of changes in the sound pressure level difference in the internal space 2S can be suppressed to be small. If the standing wave in the internal space 2S can be suppressed, the peak dip due to the standing wave does not easily appear in the sound pressure frequency characteristic of the headphones 1, and the reproduction sound quality is improved.

  Furthermore, in the case of the present embodiment, the wall surface portion 21A including the convex portion 20D is formed so that the material thickness t is thickest in the vicinity of the center of the back surface of the speaker unit 10, and from the vicinity of the center to the outer diameter direction. It is formed to become thinner as it moves on. The casing member 21D including the wall surface portion 21A uses a metal material such as an aluminum alloy or a magnesium alloy so that the material thickness t is thickest in the vicinity of the center of the back surface of the speaker unit 10 where the convex portion 20D is formed. It can be formed by a manufacturing method such as die casting. Alternatively, the housing member 21D may be formed using a resin material such as ABS resin or PP resin. Since the rigidity of the wall surface portion 21A is improved by forming the convex portion 20D, the vibration of the housing 2 can be suppressed even when the vibration from the speaker unit 10 is transmitted. As a result, the headphones 1 having excellent reproduction sound quality and stable quality can be configured.

  The convex portion 20 formed of a separate member and the connecting member 22 to which the speaker unit 10 is attached may also be formed using a metal material such as an aluminum alloy, a magnesium alloy, ABS resin, PP resin, You may form using resin materials, such as. The convex portion 20, the casing member 21 or 21D, and the connecting member 22 may be made of the same material or different materials. These have the advantage that the housing 2 can be constructed using the same or different suitable materials. When the convex portion 20 is formed by a separate member, the wall surface portion 21A of the housing member 21 to which the convex portion 20 is attached has improved rigidity and can suppress unnecessary vibration. As a result, it is possible to employ a configuration suitable for the problem of the dimensional accuracy of the parts constituting the housing 2 and the assembly dimensional accuracy of the housing, and the headphone 1 having excellent reproduction sound quality and stable quality can be configured.

  In FIG. 1, the cord and plug portion of the headphone 1 corresponding to stereo reproduction are not shown. The headphone 1 may be a wireless headphone including a cord that supplies an audio signal and a receiving unit that receives a radio signal that does not include a plug unit.

  The headphone of the present invention is not limited to the overhead type headphone as shown in the figure, and may be a headphone provided with another ear hook. Further, the present invention is not limited to headphones, and can be applied to earphones, canal-type earphones, and the like. Further, the headphones and earphones of the present invention are not limited to home stereo reproduction or multi-channel surround reproduction, and can be applied to in-vehicle audio equipment and sound reproduction facilities such as movie theaters.

DESCRIPTION OF SYMBOLS 1 Headphone 2 Housing 20, 20D Convex part 21, 21D Case member 22 Connection member 23 Hole formation member 3 Ear contact part 10 Speaker unit

Claims (2)

A speaker unit and a housing that defines an inner space provided on the back side of the acoustic radiation side of the accommodated speaker unit and an inner wall that separates an air chamber provided separately from the inner space ;
In the housing, the distance between the speaker unit and the wall surface part defining the internal space is shortened closest to the vicinity of the center of the back surface of the speaker unit, and becomes longer from the vicinity of the center toward the outer diameter direction. A first housing member having a convex portion; and a second housing member to which the speaker unit is attached and connected to the first housing member to define the internal space. The external housing communicates with the internal space. A first hole portion is formed, and a second hole portion is formed in the inner wall portion to communicate the air chamber and the internal space, and the first hole portion communicates with the outside and the internal space via the air chamber. To communicate ,
headphone. The wall surface portion including the convex portion of the housing is formed so that the material thickness is thickest in the vicinity of the center of the back surface of the speaker unit, and becomes thinner as it moves from the vicinity of the center to the outer diameter direction.
The headphones according to claim 1.