JP5747860B2 - Earpieces and headphones - Google Patents

Description

  The present invention relates to an earpiece and headphones.

There is known an inner ear type headphone that is called a canal type (or earplug type, insertion type, etc.) and has a removable earpiece.
The canal-type headphones have a sound tube portion projecting in a cylindrical shape in the housing, and are detachably fitted so that a flexible earpiece made of rubber or the like is covered with the sound tube portion. It is like that.
Further, the speaker unit is accommodated in the housing or arranged at the tip of the sound tube portion.
Such a canal type headphone has an overall shape determined so that, in use, the sound tube portion is inserted into the ear canal together with the earpiece fitted thereto, and the housing can be satisfactorily held in the auricle. Yes.

At the tip of the earpiece, an opening is formed as a sound emission hole. When the speaker unit is accommodated in the housing, the sound output from the speaker unit during use is the opening of the sound tube and earpiece. And when the speaker unit is disposed at the tip of the sound tube portion, it is discharged into the ear canal through the opening of the earpiece.
The earpiece has an umbrella-like portion that is in close contact with the inner wall of the earpiece while being inserted into the ear canal. In addition, the sound tube portion is fitted with no gap.
For this reason, the external auditory canal is generally sealed when the headphones are used, and the sound insulation is high, and noise from the outside and sound leakage from the speaker unit to the outside are satisfactorily reduced.
Therefore, the user of the canal type headphones can hear high-quality sound without being affected by external noise, and furthermore, the possibility that the leaked sound may cause discomfort to surrounding people is reduced.

On the other hand, since the canal type headphones have high sound insulation as described above, there is a problem that it is difficult to hear the sound when it is better to hear the external sound.
In order to solve this problem, Patent Document 1 proposes providing an ear cap (corresponding to an ear piece) with a vent hole for guiding external sound into the ear canal in use.

JP 2012-015589 A

By the way, in the case of canal-type headphones, in the process of inserting the earpiece into the ear canal, the umbrella-shaped portion and the ear canal are already inserted when the umbrella-shaped portion enters the ear canal entrance before the earpiece reaches a predetermined position in the ear canal. The space inside the ear canal becomes almost sealed due to close contact with the inner wall.
Therefore, when the air is pushed further from that position to a predetermined position, the air in the space in the ear canal is compressed without any escape and the pressure increases.
When the speaker unit is of a general dynamic type, the diaphragm is greatly moved in the direction of the drive shaft or is partially deformed by this high pressure (for example, it is crushed. When it is crushed, an abnormal noise is often generated). Such a phenomenon is caused.
The former causes problems such as a decrease in volume and disconnection of the voice coil, and the latter causes deterioration in sound quality and generation of abnormal sounds.

In the headphones described in Patent Document 1, when the earpiece is inserted into the ear canal, the earpiece is provided with a vent hole that allows the inside of the ear canal to communicate with the outside, so that the space in the ear canal is sealed. There is no. Therefore, the above-described problem does not occur.
However, since external noise can enter the external auditory canal in use, there is a problem that noise may be mixed with the original sound and it may be difficult for the user to listen to high-quality sound.

  Therefore, the problem to be solved by the present invention is to provide an earpiece and headphones that have high sound insulation and allow the user to listen to high-quality reproduced sound while preventing problems caused by the diaphragm accompanying wearing on the ear. It is in.

In order to solve the above problems, the present invention has any one of the following configurations 1) to 9).
1) A cylindrical base (5a) that is detachably fitted to the sound tube (1a) of the headphone (51);
Umbrella-shaped part (5b) that contacts the inner wall of the ear canal when using the headphones (51),
An earpiece with
A groove (5g) formed on the inner peripheral surface of the base (5a) from one end side to the other end side;
A valve body (5h) that is formed with flexibility at a position to close the groove (5g) and divides the groove (5g);
With
The base portion (5g) is externally fitted to the sound tube portion (1a), and the one end side is divided by the valve body (5h) by the groove portion (5g) and the sound tube portion (1a). 1 space (A) and the second space (B) on the other end side are formed,
The valve body (5h) is bent by the pressure difference (PS1) between the first space (A) and the second space (B), and the first space (A) and the second space ( The earpiece (5) is characterized in that it allows ventilation between and B).
2) The earpiece (5) according to 1), wherein a plurality of sets of the groove (5g) and the valve body (5h) are formed apart from each other in the circumferential direction.
3) The earpiece (5) according to 1) or 2), wherein the earpiece (5) has a mark (5m) visually visible according to a circumferential position of the groove (5g).
4) One of the first space (A) and the second space (B) is a space communicating with an external space when the headphones (51) are used,
The portion on the external space side in the space communicating with the external space has a larger air chamber (5j) in the radial direction of the cylindrical base portion (5a) than the other portion in the space communicating with the external space. ) Is formed, the earpiece (51) according to any one of 1) to 3).
5) Housing (1H),
A sound tube portion (1a) protruding in a cylindrical shape from the housing (1H),
A speaker unit (7) attached to the housing (1H) or the sound tube portion (1a);
An earpiece (5) that is detachably fitted to the sound tube portion (1a) and has an opening (5c) at the tip for emitting sound from the speaker unit (7);
Headphones with
Ventilation formed between the earpiece (5) and the sound tube portion (1a) and connecting the external space (V1) on the opening (5c) side and the external space (V2) on the housing (1H) side. Road (TK),
The vent passage (TK) is formed at a position where the vent passage (TK) is closed and is divided to divide the vent passage (TK), and the internal pressure on one side and the other internal pressure of the divided vent passage (TK) are divided. And a valve body (5h) that is bent by a pressure difference and allows ventilation between the one side and the other side,
A headphone (51) characterized by comprising:
6) When the pressure difference between the internal pressure on one side and the internal pressure on the other side of the divided ventilation path is equal to or greater than a predetermined value (PS1), the valve body (5h) The predetermined value (PS1) is set to allow the earpiece (5) to be used in the ear canal in order to use the headphones (51) when the ventilation path (TK) is not provided. It is smaller than the maximum value (P1) of the ear canal pressure that rises when inserted, and exceeds the maximum value (P3) of the ear canal pressure at the maximum output of the speaker unit (7) in the usage state of the headphones (51). The headphone (51) according to 5), characterized in being in a range.
7) The headphone (51) according to 6), wherein a plurality of sets of the air passage (TK) and the valve body (5h) are formed apart from each other in the circumferential direction.
8) The earpiece (5) has a mark (5m) that can be visually recognized according to the position in the circumferential direction of the air passage (TK). Headphones (51).
9) An air chamber (5j) having a larger space in the radial direction of the sound tube portion (1a) than the other portion of the air passage (TK) is provided in a portion of the air passage (TK) on the outer space side. Is the headphone (51) according to any one of 5) to 8).

  According to the present invention, it is possible to obtain an effect that the user can listen to high-quality reproduced sound with high sound insulation.

It is an external appearance perspective view which shows the headphones in embodiment of this invention. It is an external appearance perspective view which shows the earpiece in embodiment of this invention. It is sectional drawing for demonstrating the earpiece in embodiment of this invention. It is a perspective sectional view in other cutting positions for explaining an earpiece in an embodiment of the present invention. It is a fragmentary sectional view for demonstrating the headphones in embodiment of this invention. It is a fragmentary sectional view for demonstrating the principal part of the headphones in embodiment of this invention. It is a perspective view for demonstrating the function of the principal part of the earpiece in embodiment of this invention. It is a figure for demonstrating the pressure fluctuation in an ear canal. It is a fragmentary sectional view for explaining the modification of the earpiece in the embodiment of the present invention. It is a fragmentary sectional view for explaining another modification of an earpiece in an embodiment of the present invention. It is an external appearance perspective view for demonstrating the other modification of the earpiece in embodiment of this invention.

The preferred embodiments of the present invention will be described with reference to FIGS.
First, the earpiece 5 and the headphone 51 of the embodiment will be described with reference to FIGS.
FIG. 1 is a perspective view showing the overall appearance of a headphone 51 to which the earpiece 5 is attached. FIG. 2 is a perspective view showing the appearance of the earpiece 5. FIG. 3 is a longitudinal sectional view of the earpiece 5. 4 is a perspective view of a cross section at a position shifted by 90 ° around the axis with respect to FIG. FIG. 5 is a cross-sectional view of the vicinity of the sound tube portion 1a for explaining the earpiece 5 attached to the sound tube portion 1a. The cross-sectional position in FIG. 5 is set to be shifted by 90 ° around the axis (S1-S1 cross section in FIG. 4).

As shown in FIG. 1, the headphone 51 of the embodiment includes a main body portion 1, a bushing 2 provided so as to extend from the main body portion 1, and a cord 3 drawn from the tip of the bushing 2. doing.
The main body 1 has a substantially cylindrical housing 1H formed of, for example, resin, metal, wood, etc., and a cylindrical sound tube portion 1a extends from one end of the housing 1H. Yes. An earpiece 5 is detachably fitted to the sound tube portion 1a.

As shown in FIG. 5, a pan-like unit holder 6 having a slightly larger diameter than the sound tube portion 1a is fixed to the tip of the sound tube portion 1a by caulking or the like.
A speaker unit 7 is accommodated inside the unit holder 6.
A sound emitting hole (not shown) is provided in the bottom 6a of the unit holder 6. The sound output from the sound emitting surface 7a of the speaker unit 7 to the right side in FIG. 5 is emitted to the outside through the sound emitting hole. The
A pair of terminals 7 c are provided on the back surface 7 b opposite to the sound emitting surface 7 a of the speaker unit 7, and the single cords 3 a and 3 b connected to each terminal 7 c are formed as one cord 3 of the bushing 2. It extends through the inside and outside.
The bushing 2 is formed of a flexible material (rubber or the like) and is fitted into the housing 1H of the main body 1.

The earpiece 5 is formed of a flexible material such as silicone rubber.
The earpiece 5 is connected to a cylindrical base portion 5a fitted to the outer peripheral surface of the sound tube portion 1a and one end side (right side in FIG. 5) of the base portion 5a as a starting point, and the other so as to cover the base portion 5a. And an umbrella-like portion 5b extending like an jellyfish toward the end side. The umbrella-shaped portion is a portion that comes into contact with the inner wall of the ear canal so as to be softly deformed when the ear piece 5 is inserted into the ear canal.
An opening 5c having a smaller diameter than the central portion of the base 5a in the direction of the axis CL1 is provided as a sound emitting hole on one end side of the base 5a.
The inner peripheral surface of the base portion 5 a has a plurality of portions formed according to the outer peripheral diameters of the sound tube portion 1 a and the unit holder 6.
That is, the base portion 5a is formed on the opening 5c side and has a holder fitting portion 5d having an inner diameter substantially the same as the outer diameter of the unit holder 6, and a sound tube fitting portion having an inner diameter substantially the same as the outer diameter of the sound tube portion 1a. 5e, and a circumferential rib portion 5f that fits in the axial direction and the radial direction with respect to the circumferential groove portion 1a1 provided in the sound tube portion 1a.
When the earpiece 5 is fitted to the sound tube portion 1a, the holder fitting portion 5d is in close contact with the outer peripheral surface of the unit holder 6, and the sound tube fitting portion 5e is in close contact with the outer peripheral surface of the sound tube portion 1a. The portion 5f is in close contact with the outer peripheral surface of the circumferential groove portion 1a1.

In addition, the earpiece 5 has at least one place in the circumferential direction, and is a ventilation path that allows the space V1 inside the opening 5c and the space V2 outside the housing 1H to communicate with each other while being fitted to the sound tube portion 1a. Part TK.
Specifically, the ventilation portion TK is wound at a predetermined depth with a predetermined circumferential width in the holder fitting portion 5d, the sound tube fitting portion 5e, and the circumferential rib portion 5f, and along the axis CL1. It is formed with a continuous groove portion 5g. Further, the ventilation portion TK is formed with a flange-shaped flange portion 5h that closes the recess of the groove portion 5g in the width direction and divides the groove portion 5g in the direction of the axis CL1.
Specifically, in FIG. 5, the flange portion 5 h divides the space surrounded by the groove portion 5 g and the sound tube portion 1 a into a space A on the opening 5 c side and a space B on the peripheral rib portion 5 f side. Yes.
In the example shown in FIGS. 3 and 4, a pair of groove portions 5 g are provided 180 degrees apart in the circumferential direction, and the flange portions 5 h are formed at positions corresponding to the sound tube portion 1 a on the housing 1 H side with respect to the unit holder 6. ing.

Next, the detail of the collar part 5h is demonstrated with reference mainly to FIGS. FIG. 6 is a cross-sectional view taken along the line S2-S2 in FIG. 5 and is a view for explaining the groove 5g and the flange 5h.
FIG. 7 is a perspective view for explaining the bending of the flange portion 5h.
FIG. 8 is a diagram for explaining the pressure in the ear canal.

As shown in FIG. 6, the groove 5g is a groove formed in, for example, a cross-sectional arc shape, and the flange 5h has a slit 5h3 formed along the radial direction at a central position in the circumferential direction. By the slit 5h3, the flange part 5h is divided into two parts, a flange part 5h1 and a flange part 5h2.
The slit 5h3 may be a simple cut and is formed so as to have almost no gap in an unloaded state where no pressure is applied.

The flange portions 5h1 and 5h2 are formed to be relatively thin so as to bend with predetermined flexibility. Further, the tip is formed so as to contact or extremely close to the outer peripheral surface 1a2 of the sound tube portion 1a.
Accordingly, the flange portion 5h closes the groove portion 5g in a state where no pressure is applied, and sets the closed state in which no air can flow between the space A and the space B.

FIG. 7 illustrates the deformation of the flange portion 5h when a pressure difference of a predetermined value or more is generated between the space V1 and the space V2, that is, between the space A and the space B, in the usage state of the headphones 51. FIG. In FIG. 7, the sound tube portion 1 a is not shown and is shown in a perspective view from the inside.
For example, when the pressure in the space A is higher than the space B by a predetermined value or more, the flanges 5h1 and 5h2 are deformed so as to bend from the space A side to the space B side.
As a result, a gap is generated between the slit 5h3 and the tips of the flange portions 5h1 and 5h2 and the outer peripheral surface 1a2 of the sound tube portion 1a, and the air is opened from the space A side to the space B side in the groove portion 5g. Movement (see arrow) is allowed. And it is prevented that the space A becomes the high pressure more than a predetermined value with respect to the space B (outside air).

That is, when the headphone 51 to which the earpiece 5 is attached is attached to the ear, the spatial pressure in the ear canal associated with the entry of the umbrella-shaped portion 1b does not exceed a predetermined value. It does not move greatly in the direction of the drive shaft due to the pressure when it is mounted on the diaphragm, and the diaphragm itself does not partially deform.
Therefore, the headphones 51 are configured not to suffer from problems such as volume reduction, voice coil disconnection, sound quality degradation, and generation of abnormal noise caused by the diaphragm attached to the ear.

By the way, the pressure change in the ear canal in the conventional headphones is roughly divided into a pressure increase when the earpiece is inserted, a pressure increase / decrease due to a reciprocating motion accompanying vibration of the diaphragm during use, and a pressure decrease when the earpiece is removed. .
When inserting the conventional headphone into the ear, the earpiece is inserted in close contact with the ear canal while the amount of movement is about 5 mm, so the volume of the conventional headphone is reduced by this 5 mm. Thus, the air in the ear canal is compressed. Further, the air that has become high pressure in the ear canal is decompressed over time due to slight leakage or the like, and finally becomes approximately equal to the external air pressure.
At the time of extraction, conversely, the volume is expanded by the amount of movement of about 5 mm, and the air is expanded, resulting in a negative pressure.
The vibration of the diaphragm at the time of sound output is about 0.1 mm at a maximum in one amplitude, and the air is repeatedly compressed and expanded by increasing or decreasing the volume corresponding to this amount.
The half amplitude of this diaphragm is only about 2% with respect to the amount of movement during insertion (and removal). Therefore, the pressure change in the external auditory canal space during audio output is much smaller than the pressure change during insertion and removal.
The above numerical values are those for headphones of the type in which the speaker unit 7 is disposed at the tip of the sound tube portion 1a. However, even if the headphones are of the type in which the speaker unit 7 is housed inside the housing 1H, the diaphragm Is only about a few percent of the amount of movement during insertion (and removal), and the pressure change in the external auditory canal during voice output is much smaller than the pressure change during insertion and removal.

The pressure change in the ear canal in the conventional headphones is as shown in the graph of FIG. The time range in which this pressure change occurs is roughly divided into bands of an insertion area S1 corresponding to the earpiece insertion operation, a vibration area S2 corresponding to the sound output, and an extraction area S3 corresponding to the earpiece extraction operation.
In the insertion zone S1, the pressure rises until reaching a predetermined use position from the insertion until the pressure reaches the maximum pressure P1, and then gradually attenuates as the air leaks little by little and finally becomes the external pressure. Is equivalent to
In the vibration region S2, it fluctuates between a pressure P3 that is the maximum positive pressure corresponding to the maximum output and a pressure P4 that is the maximum negative pressure.
In the extraction area S3, the pressure gradually decreases to the maximum negative pressure, and when the earpiece comes out of the ear canal, it rises at once and returns to the external pressure.

Here, in the earpiece 5 of the embodiment, the threshold pressures PS1 and PS2 are preset as the minimum pressure that allows the air flow between the space A and the space B by bending the flange portion 5h, and the flange portion 5h The shape, thickness, slit insertion method, and the like are determined so as to operate as a valve body that is opened when the threshold pressure PS1 is exceeded. The threshold pressure PS2 is a pressure having the same absolute value and a reverse sign with respect to the threshold pressure PS1.
Specifically, the threshold pressure PS1 is a pressure smaller than the pressure P1 and larger than the pressure P3. The threshold pressure PS2 is a pressure that is larger than the pressure P2 (small absolute value) and smaller than the pressure P4 (large absolute value).
The threshold pressure PS1 (PS2) is preferably closer to the pressure P3 (P4) because the diaphragm is less likely to be exposed to high pressure during insertion and removal.

With this setting, the collar 5h allows air flow between the space A and the space B when the earpiece 5 is inserted into the ear canal and when the earpiece 5 is removed from the ear canal, and is attached to the ear. When the sound is output, air circulation between the space A and the space B is prohibited and the space in the ear canal is maintained in a sealed state.
The air flow in a state where the air flow between the space A and the space B is allowed is indicated by arrows in FIG. That is, the air in the space V1 enters the space B of the groove portion 5g from the space A of the groove portion 5g through the flange portion 5h that is bent to create a gap, passes through the peripheral rib portion 5f, and escapes to the outer space V2.
It should be noted that the portion adjacent to the peripheral rib portion 5f in the space B (the space near the tip of the lead line indicated by the reference sign B) is more radial than the other portions in the space B (the cylindrical base portion 5a). It is preferable to make a wide space in the circumferential direction). By providing such a wide space (air chamber 5j), a certain amount of air is accumulated, and air easily passes through the peripheral rib portion 5f and escapes to the outer space V2.

  As a result, the headphone 51 provided with the earpiece 5 does not suffer from problems such as volume reduction, disconnection of the voice coil, deterioration of sound quality, and generation of abnormal noise caused by the diaphragm accompanying insertion / extraction to the ear, and has high sound insulation. The user can listen to high-quality sound without being affected by external noise.

  It goes without saying that the embodiment of the present invention is not limited to the above-described configuration, and may be further modified without departing from the gist of the present invention.

The groove 5g is not limited to an arc-shaped cross section, and forms a space A and a space B together with the outer peripheral surface 1a2 of the sound tube portion 1a, and air flows between the space A and the space B via the flange 5h. The cross-sectional shape is not limited as long as the shape is possible.
FIG. 9 shows a modification of the groove 5g. FIG. 9 corresponds to FIG.
For example, the cross section may be rectangular as shown in FIG. 9 (a), the cross section may be triangular as shown in FIG. 9 (b), or the cross section may be a base as shown in FIG. 9 (c). It may be a shape.

On the other hand, the shape or the like of the collar portion 5h is not limited as long as the above-described threshold pressures PS1 and PS2 can be set.
FIG. 10 shows a modification of the flange portion 5h. FIG. 10 corresponds to FIG.
For example, as shown in FIG. 10A, the base 5a may be connected only at the bottom 5g1 of the groove 5g, and may be separated from the side 5g2 and 5g3 by a slit 5h3.
Further, as shown in FIG. 10B, a plurality of slits 5h3 may be provided in the flange portion 5h. The way of providing the plurality of slits 5h3 is not limited. For example, they may be parallel to each other or provided radially.

The groove 5g is not limited to the one provided along the axis CL1. For example, it may be formed in a spiral shape. Further, the circumferential position and the number of the grooves 5g are not limited.
Regarding the circumferential position where the groove 5g is provided, the cross-sectional shape of the ear canal is generally slightly long (long in the vertical direction when standing upright), so that the groove 5g is not crushed when worn on the ear. It is preferable that the sound tube portion 1a is positioned in the up-down direction (the top-neck direction when worn on the ear) so that the space can be surely secured by 5g.
Therefore, when the headphones 51 are worn on the ear, it is preferable to provide a mark 5m at a position corresponding to the groove 5g on the outer surface so that the position of the groove 5g can be visually recognized on the appearance of the earpiece 5.

FIG. 11 is an external perspective view showing the earpiece 5 provided with the mark 5m.
In this example, a mark 5m in the case where four grooves 5g are provided at intervals of 90 ° in the circumferential direction is shown. That is, the marks 5m are provided as a total of four concave portions at positions corresponding to the grooves 5g on the tip surface of the earpiece 5.
The mark 5m is, for example, a concave portion or a convex portion formed when the earpiece 5 is molded, or ink applied secondarily.

Then, when the earpiece 5 provided with the mark 5m is fitted into the sound tube portion 1a of the headphone 51, any one of the marks 5m is placed in the direction of the head (top direction) with the headphone 51 attached to the ear, Or the groove part 5g can be arrange | positioned in the direction by making it fit in the direction located in a neck direction (ground direction). Note that it is not always necessary to provide the mark 5m at a position where the groove 5g is present, and the mark 5m may be provided at a position corresponding to the position where the groove 5g is present. For example, a mark such as “front” or “rear” may be provided at a position shifted by 90 ° in the circumferential direction from the position where the groove 5g is present, depending on the position where the groove 5g is present.
Therefore, even if the cross-sectional shape of the external auditory canal is vertically long, there is almost no possibility that the groove portion 5g will be crushed in the used state, and the headphones 51 can be used in a state where sound insulation is high and high-quality reproduced sound can be heard.

  When the earpiece 5 is shared by both the headphone 51 in which the speaker unit 7 is housed in the housing 1H and the type in which the head unit 51 is disposed at the tip of the sound tube portion 1a, the former has a length of the sound tube portion 1a. Since it is short, the flange portion 5h is preferably provided in a portion close to the peripheral rib portion 5f in the groove portion 1g corresponding to the length of the sound tube portion 1a.

DESCRIPTION OF SYMBOLS 1 Main-body part 1a Sound pipe part 1a1 Circumferential groove part 1a2 Outer peripheral surface 1H Housing 2 Bushing 3 Cord 3a, 3b Single cord 5 Earpiece 5a Base part 5b Umbrella-shaped part 5c Opening part 5d Holder fitting part 5e Sound pipe fitting part 5f Circumferential rib part 5g Groove 5g1 Bottom 5g2, 5g3 Sides 5h, 5h1, 5h2 Gutter 5h3 Slit 5j Air chamber 5m Mark 6 Unit holder 6a Bottom 7 Speaker unit 7a Sound emitting surface 7b Back surface 7c Terminal 51 Headphones A, B, V1, V2 Space CL1 Axis P1 to P4 Pressure PS1, PS2 Threshold pressure S1 Insertion area S2 Vibration area S3 Removal area TK Ventilation part

Claims (9)

A tubular base that is detachably fitted to the sound tube of the headphones;
An umbrella-like portion that contacts the inner wall of the ear canal when the headphones are used;
An earpiece with
A groove formed on the inner peripheral surface of the base from one end to the other end;
A valve body that is formed with flexibility at a position to close the groove and divides the groove;
With
A first space on the one end side and a second space on the other end side divided by the valve body by the groove portion and the sound tube portion with the base portion fitted on the sound tube portion. With the formed
The valve body is bent by a pressure difference between the first space and the second space, and allows ventilation between the first space and the second space.   The earpiece according to claim 1, wherein a plurality of sets of the groove and the valve body are spaced apart in the circumferential direction.   The earpiece according to claim 1, wherein the earpiece has a mark that can be visually recognized according to a circumferential position of the groove. One of the first space or the second space is a space communicating with an external space when the headphones are used,
An air chamber having a larger space in the radial direction of the cylindrical base portion is formed in a portion on the outer space side in the space communicating with the outer space than in other portions in the space communicating with the outer space. The earpiece according to any one of claims 1 to 3, wherein: A housing;
A sound tube portion protruding in a cylindrical shape from the housing;
A speaker unit attached to the housing or the sound tube unit;
An earpiece that is detachably fitted to the sound tube portion and has an opening for emitting sound from the speaker unit at the tip;
Headphones with
An air passage formed by being surrounded by the earpiece and the sound tube portion and connecting the external space on the opening side and the external space on the housing side;
The air passage is formed to have a flexibility at a position where the air passage is blocked, and the air passage is divided, and the one bent by the pressure difference between the internal pressure on one side and the internal pressure on the other side of the divided air passage. A valve body that allows ventilation between a side and the other side;
Headphones characterized by comprising. The valve body is formed to allow ventilation between the one side and the other side when a pressure difference between the internal pressure on one side and the internal pressure on the other side of the divided ventilation path is a predetermined value or more. Has been
The predetermined value is smaller than the maximum value of the external ear canal pressure that rises when the earpiece is inserted into the ear canal to use the headphones when the ventilation path is not provided, and the speaker in the use state of the headphones The headphone according to claim 5, wherein the headphone is in a range exceeding a maximum value of the internal pressure of the ear canal at the maximum output of the unit.   The headphone according to claim 6, wherein a plurality of pairs of the air passage and the valve body are formed apart from each other in the circumferential direction.   The headphone according to any one of claims 5 to 7, wherein the earpiece has a mark visually visible according to a circumferential position of the air passage.   The air chamber having a larger space in the radial direction of the sound tube portion than the other portions in the air passage is formed in a portion on the external space side in the air passage. The headphone according to any one of 8.

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