JP2010087993A - Headphone - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a sealed type headphone for easily performing lower-register sound quality adjustment without sacrificing sound quality as an overall sound playback band. <P>SOLUTION: The present invention relates to a sealed type headphone provided with a baffle plate 2, a drive unit 3 mounted on the baffle plate 2, a case 1 which seals back sides of the baffle plate 2 and of the drive unit 3 to form a back cavity 4, and an ear pad 5 mounted on a front side of the baffle plate 2. The baffle plate 2 includes an inside/outside communicating hole 10 acoustically communicating a front cavity 6 formed from the baffle plate 2 and the ear pad 5 and the outside. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a headphone, and more particularly to a sealed headphone, characterized in that low-frequency sound quality adjustment can be easily performed without deteriorating sound quality in the entire sound range.

  8 to 10 show examples of conventional sealed headphones. 8 to 10, a baffle plate 2 is fitted into the open end of the dish-shaped case 1, and a drive unit 3 is fitted into a hole opened in the baffle plate 2. As is well known, the drive unit 3 has substantially the same configuration as the speaker unit. That is, the drive unit 3 includes a magnetic circuit constituent member (not shown) made of a yoke, magnet, pole piece, etc., a diaphragm-like diaphragm, and a magnetic gap formed by the magnetic circuit constituent member fixed to the diaphragm. And a voice coil disposed on the board.

  The drive unit 3 has a front side (lower side in FIG. 8) on which the diaphragm is disposed, and the case 1 covers and seals the back side of the baffle plate 2 and the back side of the drive unit 3. A back cavity 4 having an appropriate volume is formed between the inner surface of the case 1 and the back surface of the baffle plate 2 and the drive unit 3. A ring-shaped ear pad 5 is fixed to the outer peripheral portion on the front side of the baffle plate 2. The space surrounded by the ear pad 5 is a front cavity 6. When the user is using the ear pad 5, the ear pad 5 is pressed against the user's temporal region, and the user's ear enters the front cavity 6.

  In the sealed headphone configured as described above, an acoustic resistance material 7 is attached to the back cavity 4 as shown in FIG. 9 in order to mainly adjust the sound quality in the low frequency range. Alternatively, as shown in FIGS. 9 and 10, a hole 8 is formed in the baffle plate 2 in order to allow the back cavity 4, the Freon, and the cavity 6 to communicate with each other, and this hole 8 is formed as a braking material, that is, an acoustic resistance material having high acoustic resistance. 9 is covered. In the example shown in FIG. 9, the acoustic resistance material 7 is interposed between the inner bottom surface of the case 1 and the back surface of the drive unit 3. In the example shown in FIG. 10, a plurality of holes 6 are formed at regular intervals in the circumferential direction of the baffle plate 2, and one arcuate acoustic resistance material 9 that closes the holes 6 is formed between the baffle plate 2 and the earpad 5. It is interposed in between.

  Each of the conventional examples shown in FIGS. 9 and 10 uses an acoustic resistance material or a braking material in order to balance the reproduction frequency band. However, by using an acoustic resistance material or a braking material, the movement of the diaphragm provided in the drive unit 3 is suppressed, that is, it is difficult to move, and the sound quality of the entire sound reproduction band is sacrificed. Not desirable.

As a prior art related to the present invention, for example, there is a sealed headphone described in Patent Document 1. In the invention described in Patent Document 1, a part of the main cavity is divided into first and second subcavities by an acoustic resistance material, and the first subcavity is provided on the back surface of the drive unit, in particular, in order to improve the level of the low frequency range. The second subcavity is provided at the periphery of the housing (case).
The invention described in Patent Document 1 improves the level of the low frequency range without enlarging the case, and variously selects the first and second acoustic resistance materials, so that the frequency characteristics and sound quality can be improved over a wide frequency band. It aims to make improvements possible.

  As another prior art related to the present invention, there is an ear mounted headphone with a noise reduction function described in Patent Document 2. In the invention described in Patent Document 2, a drive unit attached to a baffle plate is covered with a housing (case), a diaphragm is attached to an opening provided in the housing, a braking member that contacts and separates from the diaphragm is provided, and the braking member is attached to the diaphragm. In the contact mode, it becomes a sealed headphone in which the cavity behind the drive unit is sealed, and in the mode in which the braking member is separated from the diaphragm, it switches to an open air type headphone that can transmit vibration via the diaphragm. It is intended to be.

JP 2003-179990 A JP 2008-66976 A

The present invention has been made to solve the above-described conventional problems. That is, an object of the present invention is to provide a sealed headphone that can easily adjust the sound quality of a low frequency without sacrificing the sound quality of the entire sound reproduction band.
Another object of the present invention is to provide a sealed headphone that can control the sound quality particularly in the low sound range without sacrificing the sound quality of the entire sound reproduction band.

  The present invention includes a baffle plate, a drive unit attached to the baffle plate, a case that forms a back cavity by sealing the back side of the baffle plate and the drive unit, and an air seal that includes an ear pad attached to the front side of the baffle plate. The headphone of the type is characterized in that the baffle plate has an inner and outer communication hole for acoustically communicating the front cavity formed by the baffle plate and the ear pad with the outside.

According to the present invention, by providing the inner and outer communication holes for acoustically communicating the front cavity and the outside, the volume of the front cavity is substantially reduced even when the user uses the front cavity even if the front cavity is sealed. The drive unit's diaphragm becomes easier to move, and the sound quality can be improved by controlling the characteristics of the low frequency range.
In addition, by covering the inner and outer communication holes with an acoustic resistance material and setting the acoustic resistance value appropriately, it is possible to control the characteristics of the low frequency range and to suppress the movement of the diaphragm to adjust the sound quality or frequency characteristics Therefore, deterioration in sound quality due to sound quality adjustment can be avoided.

  Hereinafter, embodiments of headphones according to the present invention will be described with reference to the drawings. The same components as those in the conventional example described above are denoted by common reference numerals.

  1 and 2, a baffle plate 2 is fitted into the open end of the dish-shaped case 1, and a drive unit 3 is fitted into a hole opened in the baffle plate 2. As described above, the drive unit 3 includes a magnetic circuit constituent member including a yoke, a magnet, and a pole piece (not shown), a diaphragm-like diaphragm, and a magnetic member fixed to the diaphragm and formed of the magnetic circuit constituent member. And a voice coil disposed in the gap, and has substantially the same configuration as the speaker unit.

  In the drive unit 3, the side on which the diaphragm is disposed is the front side (lower side in FIG. 1), and the case 1 covers and seals the back side of the baffle plate 2 and the back side of the drive unit 3. A back cavity 4 having an appropriate volume is formed between the inner surface of the case 1 and the back surface of the baffle plate 2 and the drive unit 3. A ring-shaped ear pad 5 is fixed to the outer peripheral portion on the front side of the baffle plate 2. The space surrounded by the ear pad 5 is a front cavity 6. When the user is using the ear pad 5, the ear pad 5 is pressed against the user's temporal region, and the user's ear enters the front cavity 6.

  The baffle plate 2 includes an inner / outer communication hole 10 that acoustically communicates the front cavity 6 formed by the baffle plate 2 and the ear pad 5 with the outside. A plurality of inner and outer communication holes 10 are provided on the outer peripheral edge of the baffle plate 2. The configuration of the baffle plate 2 will be described in more detail. The baffle plate 2 has flanges at both ends in the thickness direction, that is, in the front-rear direction, and inner and outer communication holes 10 are formed in the front flange. The front cavity 6 and the outside communicate with each other through a space between them.

  In the illustrated first embodiment, the baffle plate 2 has a front-rear communication that acoustically connects the back cavity 4 and the front cavity 6 to the inner peripheral side of the inner and outer communication holes 10 in addition to the inner and outer communication holes 10. A plurality of holes 8 are provided. The ear pad 5 is fixed along the outer periphery on the front side of the baffle plate 2, and an acoustic resistance material 9 is interposed between the front surface of the baffle plate 2 and the ear pad 5, and the acoustic resistance material 9 is connected to the inner and outer communication holes 10. Covers the front. The front cavity 6 and the inner and outer communication holes 10 communicate with each other through the acoustic resistance material 9, and as a result, the front cavity 6 communicates with the outside.

  As shown in FIG. 2, the acoustic resistance material 9 is formed by cutting a part of a ring-shaped plate, that is, in a partial arc shape, and covers the inner and outer communication holes 10 as well as the front and rear communication holes 8. In other words, the inner and outer communication holes 10 and the front and rear communication holes 8 are covered with the common acoustic resistance material 9. However, as shown in FIG. 2, the acoustic resistance material 9 covers a part of the plurality of front and rear communication holes 8 so as to cover the acoustic terminal between the back cavity 4 and the front cavity 6 formed by the front and rear communication holes 8. The acoustic resistance can be adjusted.

  According to the first embodiment described above, the front cavity 6 is hermetically sealed when the user uses it by providing the inner and outer communication holes 10 for acoustically communicating the front cavity 6 and the outside. However, since the volume of the front cavity 6 is substantially enlarged, the diaphragm of the drive unit 3 can be moved easily, and the sound pressure in the low frequency range is suppressed to improve the sound quality in the low frequency range. it can. FIG. 7 shows the frequency characteristics of the headphones according to the present invention and the conventional headphones as shown in FIG. The horizontal axis represents frequency and the vertical axis represents sound pressure. A solid line A indicates the characteristics of the conventional headphones, and a broken line B indicates the characteristics of the headphones according to the present invention. As can be seen from FIG. 7, according to the headphones of the present invention, the characteristics of the low frequency range are well controlled and the sound quality is improved.

  Further, by covering the inner and outer communication holes 10 with the acoustic resistance material 9 and appropriately setting the acoustic resistance value, the characteristics of the low frequency range can be controlled, and the diaphragm of the drive unit 3 can be adjusted to adjust the sound quality (frequency characteristics). Therefore, it is possible to avoid deterioration of sound quality due to sound quality adjustment.

  In the embodiment shown in FIGS. 1 and 2, the inner and outer communication holes 10 and the front and rear communication holes 8 are covered with a common acoustic resistance material 9. However, as in the second embodiment shown in FIGS. An acoustic resistance material 12 that covers only the hole 10 may be used. In addition to the acoustic resistance material 12, an acoustic resistance material covering the front and rear communication holes 8 may be used.

  In the embodiment shown in FIGS. 1 and 2, the inner and outer communication holes 10 and the front and rear communication holes 8 are circular holes, but may be rectangular holes as shown in FIG.

  5 and 6 show a third embodiment of the headphones according to the present invention. This embodiment is different from the above embodiment in that it has a sound quality adjusting member 14 that performs sound quality adjustment by opening and closing the inner and outer communication holes 10. 5 and 6, the sound quality adjusting member 14 is slidably provided along the outer peripheral edge of the baffle plate 2, and is configured so that the inner and outer communication holes 10 can be opened and closed by sliding the sound quality adjusting member 14. ing. FIG. 5 shows a state in which the sound quality adjusting member 14 opens the inner / outer communication hole 10, and the frequency characteristic in this state is as shown by a curve indicated by a broken line B in FIG. 7. FIG. 6 shows a state in which the sound quality adjusting member 14 closes the inner and outer communication holes 10, and the frequency characteristic in this state is as shown by a curve indicated by a solid line A in FIG. Thus, when the sound quality adjusting member 14 opens and closes the inner and outer communication holes 10, the sound pressure of the lowest frequency that can be reproduced changes to P1 or P2, as shown in FIG.

  The sound quality adjusting member 14 may be switched between a state in which the inner and outer communication holes 10 are fully opened and a state in which the inner and outer communication holes 10 are all closed, or the degree of opening and closing of the inner and outer communication holes 10 may be adjusted. If the degree of opening / closing is adjustable, the frequency characteristic can be adjusted between the curve A and the curve B shown in FIG.

  5 and 6, one sound quality adjusting member 14 is configured to open and close one inner / outer communication hole 10, but a plurality of sound quality adjusting members 14 capable of opening and closing a plurality of inner and outer communication holes 10 are integrally formed. A plurality of inner and outer communication holes 10 may be opened and closed simultaneously by being connected and moving integrally. Further, the degree of opening / closing of the plurality of internal and external communication holes 10 may be adjusted simultaneously by the plurality of sound quality adjusting members 14.

1 is a longitudinal sectional view showing a first embodiment of a headphone according to the present invention. It is a front view of the baffle board of the said Example. It is a front view of the baffle board in the modification of the headphones concerning the present invention. FIG. 4 is an enlarged view of a cross section taken along line AA ′ in FIG. 3. It is a front view of the baffle board in 2nd Example of the headphones which concern on this invention. It is a front view of the baffle board in a different mode of the above-mentioned 2nd example. 6 is a graph showing a comparison of frequency characteristics in the low sound range between the headphones according to the present invention and the sealed headphones of the conventional example. It is a longitudinal cross-sectional view which shows the example of the conventional sealed headphones. It is a longitudinal cross-sectional view which shows another example of the conventional sealed headphones. It is a front view of the baffle board in the above-mentioned conventional headphones.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Case 2 Baffle board 3 Drive unit 4 Back cavity 5 Ear pad 6 Front cavity 8 Front-rear communication path 9 Acoustic resistance material 10 Inner / outer communication path 12 Acoustic resistance material 14 Sound quality adjustment member

Claims (8)

A sealed headphone with a baffle plate, a drive unit attached to the baffle plate, a case that forms a back cavity by sealing the back side of the baffle plate and the drive unit, and an ear pad attached to the front side of the baffle plate There,
The baffle plate is a headphone having an internal / external communication hole for acoustically communicating a front cavity formed by the baffle plate and an ear pad and the outside.   The headphone according to claim 1, wherein a plurality of inner and outer communication holes are provided at an outer peripheral edge of the baffle plate.   The headphone according to claim 2, wherein the baffle plate has front and rear communication holes that acoustically communicate the back cavity and the front cavity on the inner peripheral side of the position where the inner and outer communication holes are formed.   The headphone according to claim 2, wherein the inner and outer communication holes are covered with an acoustic resistance material.   The headphone according to claim 3, wherein the inner and outer communication holes and the front and rear communication holes are covered with a common acoustic resistance material.   The headphone according to claim 4 or 5, wherein the acoustic resistance material is interposed between the baffle plate and the ear pad.   The headphone according to claim 1, further comprising a sound quality adjusting member that performs sound quality adjustment by opening and closing the inner and outer communication holes.   The headphone according to claim 7, wherein the sound quality adjusting member is capable of adjusting an opening / closing degree of the inner and outer communication holes.

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