JP5573574B2 - Sound equipment - Google Patents

Description

  The present invention relates to an acoustic device such as an earphone, and more particularly to a cord retaining structure for transmitting an audio signal.

JP 2009-165155 A JP-A-2005-349508

In an acoustic device such as an earphone, a speaker, or a microphone, a cord serving as an audio signal transmission path is connected to the housing.
In order to prevent the cord from coming off even if the cord is pulled during use, a device for preventing the cord from coming off in the housing has been devised.
In order to form the cord stopper, both the core wire and the sheath of the cord must be fixed in the casing.

  As one of the simplest techniques, as described in the above-mentioned Patent Document 1, a cord (core wire and sheath) is formed by making a knotted ball of the cord itself and locking the knotted ball portion within the housing. Those that prevent omission are known.

  An example of using knot balls is schematically shown in FIG. 7 (d), and a knot ball portion M of the cord 70 itself is formed so as not to come out of the housing (51, 53).

The method of making knot balls is highly reliable as a stopper. However, by tying the cord itself, the diameter of the knot is usually about three times the cord diameter.
In order to store the knotted ball portion in the housing, a relatively large volume is required as a space in the housing. For this reason, it is disadvantageous for reducing the size of the housing of the acoustic device.
In particular, in the earphone, if the housing size is large, the housing interferes with the auricle when the user wears it on the auricle, which deteriorates the wearability. For this reason, it is important to reduce the housing size in the earphone, but in that case, it is not preferable that the size reduction is limited by the knotting ball of the cord.

  Therefore, an object of the present invention is to provide a retaining structure effective for both the sheath and the core wire while being suitable for downsizing the housing.

The acoustic device of the present invention houses a cord in which a plurality of core wires forming an audio signal transmission path are covered with a sheath, and an acoustic device portion to which the plurality of core wires of the introduced cord are electrically connected. A housing. An engagement portion that engages with the sheath of the introduced cord is formed in the housing. Further, in the casing, the plurality of core wires in a portion where the sheath is peeled off are connected to the acoustic device portion via knotted ball portions in which the core wires are connected to each other.
The sheath of the cord has an engaged portion that engages with the engaging portion of the housing.
In the cord, a plurality of core wires are divided into two or more core lines in the sheath.
Alternatively, in the cord, a plurality of core wires are arranged in a single core line in the sheath, and the plurality of core wires in a portion where the sheath is stripped in the casing are each core wire. The knotted ball portion is formed through a portion where the path is separated by the separating structure formed in the housing.

  The acoustic device unit is an acoustic conversion device that outputs sound based on an audio signal transmitted by the cord, and the housing includes an earpiece unit that is inserted into a user's ear hole, An earphone housing in which a sound path for guiding the sound output from the acoustic conversion device to the earpiece unit is formed. For example, the acoustic conversion device is formed of a balanced armature unit.

  In the present invention, since the knot is made only by the core wires arranged in the sheath, the diameter of the knot is not so large. With the knotted ball, each core wire can prevent the sheath from coming off. On the other hand, the sheath side is locked by the engagement piece in the device casing, so that the removal preventing action is obtained.

According to the present invention, both the sheath and the core wire in the cord can be appropriately prevented from coming out, and the knotting ball does not require a relatively large volume in the housing, which is suitable for downsizing of the acoustic device. It can be a structure.
In particular, in the case of earphones, it is possible to reduce the size of the housing and contribute to improving the wearability to the auricle.

1 is a plan view, a side view, a bottom view, a front view, and a perspective view of an acoustic conversion device mounted on an earphone according to an embodiment of the present invention. It is a disassembled perspective view of the acoustic converter of embodiment. It is sectional drawing which shows the internal structure of the acoustic converter of embodiment. It is a perspective view of the earphone of an embodiment. It is explanatory drawing of the example of the 1st retaining structure of embodiment. It is explanatory drawing of the code | cord | chord in the 1st retaining structure of embodiment. It is explanatory drawing of the effect of the 1st retaining structure of embodiment. It is explanatory drawing of the code | cord | chord of the 2nd example of retaining structure of embodiment. It is explanatory drawing of the 2nd example of retaining structure of embodiment. It is explanatory drawing of the code | cord | chord of the 3rd example of retaining structure of embodiment. It is explanatory drawing of the 3rd example of retaining structure of embodiment.

Hereinafter, as an embodiment of the acoustic device of the present invention, an earphone will be described as an example and described in the following order.
<1. Structure of acoustic transducer mounted on earphone>
<2. Example of first retaining structure of earphone>
<3. Second example of retaining structure of earphone>
<4. Third example of retaining structure of earphone>
<5. Modification>

<1. Structure of acoustic transducer mounted on earphone>

The earphone of the embodiment is an example in which an acoustic conversion device of a type called a balanced armature unit is mounted in a structure described later with reference to FIG. The earphone according to the embodiment is characterized by a cord retaining structure. Prior to the description of the retaining structure, the balanced armature unit will be described.

  1A to 1E are a plan view, a side view, a bottom view, a front view, and a perspective view of an acoustic conversion device 1 mounted on an earphone according to an embodiment.

In the acoustic transducer 1, the storage unit 4 is formed by the case body 26 and the cover body 27 shown in FIG. The storage unit 4 serves as a housing of the acoustic transducer 1, and a yoke, a coil, an armature, a diaphragm, and the like are disposed therein as will be described later.
A circuit board 8 (flexible board) is led out from the storage unit 4. The circuit board 8 is formed with a circuit portion for supplying a drive signal to an internal coil.

  An audio output hole 27 a is formed on the upper surface of the cover body 27 that forms the storage unit 4. The sound output hole 27a is formed in a surface facing the vibration surface of an internal diaphragm unit 3 to be described later in the storage unit 4.

FIG. 2 is an exploded perspective view of the acoustic conversion device 1, and FIG. 3 is a cross-sectional view of the acoustic conversion device 1. An example of the internal structure of the acoustic transducer 1 will be described with reference to FIGS.
In the following description of the structure of the acoustic transducer 1, the side expressed in the front view of FIG. 1 (d) is the front, the direction in which the circuit board 8 is derived is the rear, and the front / rear / up / down / left / right expressions are used. However, the front, rear, upper, lower, left and right are merely for convenience of explanation.

  As shown in FIGS. 2 and 3, the acoustic conversion device 1 is configured by storing a drive unit 2 and a diaphragm unit 3 in a storage unit 4.

The drive unit 2 includes a yoke 5, a pair of magnets 6, 6, a coil 7, a circuit board 8, and an armature 9.
The yoke 5 is composed of a flat plate-like first member 10 facing in the up-down direction and a U-shaped second member 11 opened upward. The left and right side surfaces of the first member 10 are attached to the inner surface side of the side surface portion of the second member 11 by, for example, adhesion. As a result, the yoke 5 is formed in a rectangular tube shape in which the first member 10 and the second member 11 are joined and penetrated back and forth.

  A pair of magnets 6 and 6 are attached in the yoke 5. The magnets 6 and 6 are arranged in a state of being spaced apart from each other in the vertical direction and facing each other, and the poles on the opposite sides are different. The upper magnet 6 is attached to the lower surface of the first member 10, and the lower magnet 6 is attached to the upper surface of the bottom surface of the second member 11.

The coil 7 is formed in a cylindrical shape whose axial direction is the front-rear direction, and is formed in, for example, a long hole shape when viewed from the front-rear direction. The coil 7 is wound in an aligned manner, and the upper surface and the lower surface are each formed in a planar shape.
The circuit board 8 is attached to the upper surface of the coil 7. The circuit board 8 has a length in the front-rear direction that is longer than the length in the front-rear direction of the coil 7, and a part of the circuit board 8 is attached to the upper surface of the coil 7. The substantially rear half of the circuit board 8 protrudes rearward from the coil 7, and the rear side is led out from the storage unit 4.
Both ends of the coil 7 are connected to predetermined terminals on the circuit board 8, and an electric circuit for applying a drive current to the coil 7 is formed.
Since the coil 7 is wound in an aligned manner and the upper surface is formed in a flat shape, a good bonding state between the coil 7 and the circuit board 8 can be ensured.

Each part of the armature 9 is integrally formed of a magnetic metal material.
The armature 9 includes a coil mounting portion 12 that faces in the vertical direction, a connecting portion 13 that protrudes upward from the rear end portion of the coil mounting portion 12, and a vibrating portion 14 that protrudes forward from the upper end portion of the connecting portion 13. Side wall portions 15 and 15 projecting upward from the left and right end portions of the coil attachment portion 12, respectively, and fixed portions 16 and 16 projecting forward from the front surfaces of the substantially upper half portions of the side wall portions 15 and 15, respectively. Are integrally formed.

The vibration part 14 has a length in the front-rear direction that is longer than a length in the front-rear direction of the coil attachment part 12, and a front end is positioned forward of the front end of the coil attachment part 12.
A connecting concave portion 14a that opens forward is formed at the center of the front surface of the vibration portion 14 in the left-right direction.
The upper surfaces of the side wall portions 15 and 15 and the upper surfaces of the fixed portions 16 and 16 are the same plane, and the same planes spaced apart on the left and right are formed as the fixing surfaces 17 and 17, respectively.
For example, the coil 7 is attached to the upper surface of the coil attachment portion 12 by adhesion. Since the coil 7 is wound in an aligned manner and the bottom surface is formed in a flat shape, a good bonding state of the coil 7 with respect to the coil mounting portion 12 can be ensured.

As can be seen from FIG. 3, in the state where the coil 7 is attached to the coil attachment portion 12, the vibration portion 14 is penetrated through the coil 7 and a part thereof is protruded forward from the coil 7.
In the acoustic conversion device 1, the armature 9 is provided with a coil attachment portion 12 to which the coil 7 is attached and a vibration portion 14 that penetrates the coil 7. Therefore, the position of the vibration part 14 with respect to the coil 7 can be ensured with high accuracy, and the position accuracy of the vibration part 14 with respect to the coil 7 can be improved.
In the armature 9, the fixed portions 16 and 16 are fixed to the outer surface of the side surface portion of the yoke 5 by adhesion, welding, or the like in a state where the coil 7 is attached to the coil attachment portion 12. In the state where the armature 9 is fixed to the yoke 5, the upper surface of the side surface of the yoke 5 is positioned slightly above the fixed surfaces 17, 17 of the armature 9. Further, the connecting recess 14 a formed at the front end portion of the vibrating portion 14 is positioned slightly forward from directly below the front end portions of the magnets 6 and 6.

  Here, the armature 9 in which the respective parts are integrally formed is shown as an example. However, in the armature, at least the vibrating part, which is a magnetized part, may be formed of a magnetic metal material.

The diaphragm unit 2 includes a holding frame 20, a resin film 21, a diaphragm 22 and a beam portion 23.
For example, the holding frame 20 is formed in a vertically long frame shape with a metal material, and the width in the left-right direction is substantially the same as the width in the left-right direction of the armature 9.
The resin film 21 has the same size as the outer shape of the holding frame 20, and is attached to the upper surface of the holding frame 20 by adhesion or the like so as to close the opening of the holding frame 20, for example.

The diaphragm 22 is formed in a rectangular shape whose outer shape is made slightly smaller than the inner shape of the holding frame 20 by using a thin metal material such as aluminum or stainless steel. The vibration plate 22 is provided with reinforcing ribs 22a, 22a, 22a that extend in the front-rear direction and are spaced apart from each other in the left-right direction.
For example, the diaphragm 22 is in a state of being attached to the resin film 21 from below.
The rear end of the diaphragm 22 is positioned slightly forward from the inner surface of the rear end portion of the holding frame 20, and a gap is formed between the rear end of the diaphragm 22 and the inner surface of the rear end portion of the holding frame 20. Yes. As shown in FIG. 3, an adhesive 24 is applied so as to fill this gap. Therefore, the diaphragm 22 and the holding frame 20 are coupled via the adhesive 24 and the resin film 21.
As the adhesive 24, for example, an acrylic non-curable adhesive or an acrylic ultraviolet curable adhesive is used.
The adhesive 24 fills the gap and extends on the surface of the diaphragm 22 opposite to the side attached to the resin film 21. That is, the diaphragm 22 is supported by the holding frame 20 by the resin film 21, but functions as a reinforcing member that reinforces it.

  The beam portion 23 is formed integrally with the diaphragm 22, and is formed, for example, by bending a part of the diaphragm 22 downward. The beam portion 23 is formed in, for example, a narrow plate shape extending vertically.

The diaphragm unit 3 is fixed to the drive unit 2 from above by, for example, adhesion or laser welding. That is, the diaphragm unit 3 is fixed by joining the lower surface of the holding frame 20 to the fixing surfaces 17 and 17 of the armature 9.
Further, when the diaphragm unit 3 is fixed to the drive unit 2, the lower end portion of the beam portion 23 is attached to the front end portion of the vibration portion 14 in the armature 9 by bonding. That is, the beam portion 23 is connected to the armature 9 by the adhesive 25 in a state where the beam portion 23 is inserted into the connection recess 14 a formed in the vibration portion 14.
As described above, since the beam portion 23 is formed integrally with the vibration plate 22, the vibration plate 22 and the armature 9 are connected via the beam portion 23 only by attaching the lower end portion of the beam portion 23 to the vibration portion 14. Thus, a structure for transmitting the vibration of the vibrating portion 14 of the armature 9 to the diaphragm 22 is formed.
The shape of the beam portion 23 is not limited to a narrow plate shape.

As described in FIG. 1, the storage unit 4 includes a box-shaped case body 26 opened upward and a shallow box-shaped cover body 27 opened downward.
The case body 26 is formed with an audio output hole 27a on the upper surface thereof. The surface on which the sound output hole 27a is formed is a surface facing the vibration surface of the internal diaphragm 22.
As shown in FIG. 3, sound due to vibration of the diaphragm 22 is emitted to the space 31 on the vibration surface, and this sound is output from the sound output hole 27 a formed at a position facing the vibration surface. .

In the acoustic conversion device 1 having such a structure, when the drive current based on the audio signal is applied to the coil, the vibrating portion 14 of the armature 9 inserted between the magnets 6 and 6 of the coil 7 and the yoke 5 is provided. Vibrate.
The vibration of the vibration part 14 is transmitted to the diaphragm 22 via the beam part 23, and the diaphragm 22 vibrates. The sound generated by the vibration of the diaphragm 22 is emitted to the space 31 on the vibration surface shown in FIG. 3, and this sound is output from the sound output hole 27a formed on the surface facing the vibration surface. It becomes.

<2. Example of first retaining structure of earphone>

As a cord retaining structure of the earphone according to the embodiment, a first retaining structure example will be described.
4A and 4B are perspective views showing the appearance of the earphone 50. FIG. The housing of the earphone 50 is formed by joining a front housing 52 and a rear housing 51.
An earpiece 53 to be inserted by the user into the ear canal is attached to the front housing 52.
A cord 70 for supplying an audio signal is introduced and fixed in the earphone housing.

  FIGS. 5A and 5B show structural examples of the earphone 50. FIG. 5A shows a state in which the cord 70 is omitted, and FIG. 5B shows a state in which the cord 70 is fixed.

As shown in FIGS. 5A and 5B, the front housing 52 and the rear housing 51 are joined by, for example, ultrasonic welding or a technique using an adhesive to form each space in the earphone housing. Is done.
That is, the sound path tube 90 is formed inside the front housing 52 side. A storage space 91 is formed by the front housing 52 and the rear housing 51. A cord space 92 into which the cord 70 is inserted is formed on the rear housing 51 side.
In this example, the inner lid member 54 is used. The inner lid member 54 is attached so as to be crimped to the cord 70 side in a state where the end portion of the cord 70 is set in the cord space 92 of the rear housing 51 as shown in FIG. For example, the inner lid member 54 is fixed to the rear housing 51 using ultrasonic welding or an adhesive. The inner lid member 54 partitions the storage space 91 and the cord space 92 in the housing.

  For example, an earpiece 53 formed of, for example, a flexible material is engaged and attached to the front housing 52. In this state, the sound emission hole 53 a of the earpiece 53 is in a state of linearly communicating with the sound path tube 90.

In the case of this example, the above-described acoustic conversion device 1 as a balanced armature unit is fixedly disposed in the storage space 91. As described above, in the acoustic conversion device 1, the audio output hole 27a is formed on the upper surface of the casing (the cover body 27).
As can be seen from FIGS. 5 (a) and 5 (b), the sound output hole 27 a of the acoustic conversion device 1 is acoustically connected to the sound path tube 90. With this structure, the sound output from the acoustic conversion device 1 reaches the sound emission hole 53a of the earpiece 53 through the sound path tube 90, and reaches the ear hole of the user wearing the earphone 50.

The circuit board 8 derived from the acoustic conversion device 1 has two core wires derived from the cord 70 inserted into the cord space 92 (L-channel or R-channel audio signal line and ground line). Is soldered and connected.
As a result, either the L channel or the R channel audio signal is supplied to the acoustic conversion device 1, and a drive current based on the audio signal flows through the internal coil 7. When the drive current flows, sound is output from the sound output hole 27a due to vibration of the internal diaphragm 22, and the sound passes through the sound path tube 90 and the sound output hole 53a as described above, and the user's ear hole. To reach.

As a retaining structure for the cord 70, an engagement piece 51 a that projects into the cord space 92 is formed in the rear housing 51. The engaging piece 51 a engages with a concave portion as the engaged portion 73 formed in the sheath 71 of the cord 70.
Further, the two core wires 72, 72, which are derived by peeling off the sheath of the cord 70 from the sheath 71, are formed with a knotted ball portion M in which the core wires are bonded to each other. 54 is led to the circuit board 8 through the opening 54a, and is soldered.

The structure of the cord 70 is shown in FIGS. FIG. 6A is a perspective view of the end portion of the cord 70, and FIG. 6B shows a cross section taken along the line AA in FIG.
The sheath 71 which is a covering body of the cord 70 has a flat shape. In such a flat cord 70, two core wires 72, 72 are disposed inside the sheath 71. Each core wire 72 has an insulating portion 75 formed around the copper wire 76.
For example, in a cord 70 attached to an L-channel earphone unit, the copper wire 76 of one core wire 72 is used as a transmission channel for an L-channel audio signal, and the copper wire 76 of the other core wire 72 is used as a common line (ground line). .
The two core wires 72, 72 are divided into two core lines 78, 78 inside the sheath 71, and are arranged respectively.

Further, the sheath 71 is formed with an engaged portion 73 at a position corresponding to the engaging piece 51 a when the sheath 71 is disposed in the cord space 92 in the rear housing 51.
As shown in the figure, the engaged portion 73 has a recess formed in the sheath 71 at a portion between the two core lines 78 and 78.

As described above, the engagement piece 51 a is formed in the rear housing 51 as a structure for preventing the cord 70 from coming off. The engagement piece 51 a is engaged with the engaged portion 73 formed in the sheath 71. Thus, the sheath 71 can be prevented from coming off.
FIG. 7A is a plan view of the cord, and FIG. 7B is a simplified diagram showing a state in which the cord 70 is disposed in the earphone housing. FIG. 7C shows a BB cross section of FIG.
As can be seen from FIGS. 7B and 7C and FIG. 5B, the engaging piece 51 a engages with the engaged portion 73. That is, the cord 70 is engaged with the engaging piece 51 a and the engaged portion 73 while being pressed by the inner lid member 54 in the cord space 92 formed by the inner lid member 54 and the rear housing 51. Fixed and fixed. Since the engagement piece 51a and the engaged portion 73 are engaged, even if the cord 70 is pulled in the removal direction, the removal of the cord 70 is prevented.

However, the engagement between the engagement piece 51a and the engaged portion 73 directly exhibits the effect of preventing the sheath 71 from coming off from the earphone housing. Of course, this alone is highly effective in preventing the disconnection, but in this example, the core wires 72 and 72 are also prevented from being directly disconnected.
That is, as shown in FIGS. 6C and 7A, the two core wires 72 and 72 led out from the sheath 71 are connected to each other to form a knotted ball portion M.
Then, as shown in FIG. 5B, the core wires 72 and 72 are guided to the circuit board 8 side and connected to the circuit.

  The two core wires 72 and 72 pass through different core lines 78 and 78 in the sheath 71, respectively. For this reason, even if the situation where only the core wires 72 and 72 are pulled occurs due to the formation of the knotted ball portions M of the core wires 72 and 72, the knotted ball portions M abut against the end of the sheath 71. In this case, only the core wires 72, 72 are not pulled out.

  As described above, in this example, the knotted ball portion M is formed on the core wires 72 and 72 and the external force that the core wires 72 and 72 are pulled out from the sheath 71 can be countered, and the sheath 71 further includes the engaging piece 51a and the engaged portion. By engaging 73, it is possible to counter an external force that causes the sheath 71 to be pulled out. As a result, appropriate removal prevention is realized for both the sheath 71 and the core wires 72 and 72.

In this example, an appropriate retaining structure is realized, and in this example, the earphone housing is suitable for downsizing.
If a knotted ball portion M of the cord itself is made to obtain a retaining effect as in the conventional case, a large volume for storing the knotted ball portion M is provided in the earphone housing as shown in FIG. Necessary. This is because the knotted ball portion M has a diameter about three times the diameter of the cord 70.
However, in the case of the present embodiment, the knotted ball portion M is formed by the core wires 72, 72, and therefore the knotted ball portion M does not become large. Actually, the diameter of the knotted ball may be equal to or smaller than the cross-sectional size (thickness) of the sheath 71.
Now, assuming that the cord thickness is equivalent, the thickness Ta of the required space in the housing when the method of forming the knotted portion M of the core wires 72, 72 as in the present embodiment is used is the conventional cord itself When forming the knot ball, a thickness reduction of 30% or more can be expected with respect to the thickness Tb of the necessary space.

  Thus, in this Embodiment, the storage space volume by the knotted ball part M can be reduced significantly. Therefore, the earphone housing itself can be reduced in size. This is very advantageous for improving the wearability when the user wears the ear.

In the case of this example, a balanced armature unit is employed as the acoustic transducer 1. The balanced armature unit is a component in which the components of the acoustic conversion device 1 are compactly housed in a storage unit, and is suitable for small devices, which contributes to the miniaturization of the earphone housing.
Further, as shown in FIG. 5, in this example, the sound output hole 27a of the balanced armature unit directly outputs sound to the sound path tube 90 in the earphone housing. There is no need for an internal structure or separate parts for guiding the sound to the tube 90. This also contributes to the miniaturization of the earphone housing.
As described above, the present embodiment is effective for reducing the size of the earphone housing both in the structure for preventing the cord 70 from coming off and in the configuration of the acoustic conversion device 1 and the output sound path.

<3. Second example of retaining structure of earphone>

A second retaining structure example will be described with reference to FIGS. FIG. 8A shows a perspective view of the cord 70, and FIG. 8B shows a CC cross section of FIG. 8A.
As shown in FIG. 8A, an example is shown in which a round cord 70 is used.
A sheath 71 that is a covering body of the cord 70 has a circular cross section, and two core wires 72 are disposed inside the sheath 71. The two core wires 72, 72 are divided into two core lines 78, 78 inside the sheath 71, respectively.

In addition, the sheath 71 is formed with an engaged portion 73 that is engaged when the sheath 71 is disposed in the cord space 92 in the rear housing 51.
In this case, the engaged portion 73 has two recesses formed along the peripheral surface of the sheath 70 as shown in the figure.

FIG. 9 shows a state where the cord 70 is fixed in the earphone housing. Note that the same parts as those in FIG.
In the case of this example, an engagement piece 51 a that projects into the cord space 92 is formed on the rear housing 51 side in the earphone housing, and the inner lid member 54 also engages into the cord space 92. A piece 53a is formed.
The engagement pieces 51a and 53a engage with the engaged portions 73 and 73 of the sheath 71 from both sides, respectively, thereby preventing the sheath 71 from coming off.

  The retaining of the core wires 72, 72 is the same as that of the first structural example described above. That is, the core wires 72 and 72 are connected to each other as shown in FIG. 8A to form a knotted ball portion M, and after passing through the knotted ball portion M as shown in FIG. 9, the core wires 72 and 72 are guided to the circuit board 8 side. To be connected to the circuit.

This second structural example can achieve the same effect as the first structural example described above. That is, the earphone housing can be miniaturized while preventing the sheath 71 and the core wires 72 and 72 from coming off.
Further, although it is not directly depending on whether the cord 70 is round or flat, if the depth of the recessed portion of the engaged portion 73 is not so large, as in the second structural example, In addition, by providing two engaged portions 73 and engaging the two engagement pieces 51a and 53a in the earphone housing, sufficient strength for preventing the sheath 71 from coming off can be obtained.

<4. Third example of retaining structure of earphone>

A third retaining structure will be described with reference to FIGS.
FIG. 10A is a perspective view of the cord 70, and FIG. 10B shows a DD cross section of FIG.

As shown in FIG. 10A, a round cord 70 is used.
A sheath 71 that is a covering body of the cord 70 has a circular cross section, and two core wires 72 are disposed inside the sheath 71. However, in this example, the two core wires 72 and 72 are arranged together in one core line 78 inside the sheath 71.

In addition, the sheath 71 is formed with an engaged portion 73 that is engaged when the sheath 71 is disposed in the cord space 92 in the rear housing 51.
In this case, the engaged portion 73 is formed with a groove-like recess that circulates around the peripheral surface of the sheath 70 as shown in the figure.

FIG. 11 shows a state in which the cord 70 is fixed in the earphone housing. Note that the same parts as those in FIG.
In the earphone housing, an engaging piece 51a that protrudes into the cord space 92 is formed on the rear housing 51 side, and an engaging piece 53a that protrudes into the cord space 92 is also formed on the inner lid member 54. ing. For example, in a state where the inner lid member 54 is fixed to the rear housing 51, the engagement pieces 51a and 53a are formed to form ring-shaped protrusions, which are formed in the groove-shaped covering shown in FIGS. 10 (a) and 10 (b). Engage with the engaging portion 73. Note that the engagement pieces 51a and 53a do not necessarily have to form ring-shaped protrusions. In other words, any shape that engages with at least a part of the groove as the engaged portion 73 may be used.
The engagement pieces 51 a and 53 a engage with the engaged portion 73 on the peripheral surface of the sheath 71, thereby preventing the sheath 71 from coming off.

In order to prevent the core wires 72 and 72 from coming off, a separation pin 51 b that separates the paths of the core wires 72 and 72 in the housing is provided in the rear housing 51.
In this case, since the core wires 72 and 72 pass through the common core line 78, even if the knotted ball portion M is formed at the portion where the sheath 71 is peeled off, the core wires 72 and 72 are not sufficiently prevented from coming off.
Therefore, as shown in FIG. 11, the paths of the core wires 72, 72 led out from the sheath 71 are once divided by the separation pins 51b. Thereafter, the core wires 72 and 72 are connected to each other to form a knotted ball portion M. And it is made to connect with the circuit board 8 through the opening 54a through the knotted ball portion M.
In this way, since the knotted ball portion M is locked by the separating pin 51b, the core wires 72, 72 can realize a strong retaining of the core wires 72, 72.

This third structural example can also achieve the same effect as the first structural example described above. That is, the earphone housing can be miniaturized while preventing the sheath 71 and the core wires 72 and 72 from coming off.

<5. Modification>

As mentioned above, although the various structural examples as embodiment were demonstrated, the structure of the earphone of this invention is not limited to said each example.
There are many possible external shapes and internal structures of the earphone housing. In any case, a structure that engages with the sheath 71 may be taken in the earphone housing.

Regarding the retaining structure of the sheath 71, the following modified examples are also conceivable.
For example, in FIGS. 6A and 6B, the engaged portion 73 is a recess, but the engaged portion 73 may be formed as a through hole as shown in FIG. 6D. In the earphone housing, the engagement piece 51a is inserted into the through hole and the sheath 71 is locked.

  In each of the above examples, the engaging piece 51a (and 53a) is given as an example of the engaging portion in the earphone housing, and the engaged portion 73 on the sheath 71 side is a concave portion, but the concave and convex portions may be reversed. That is, the engaged portion on the sheath 71 side is, for example, a convex portion formed on the outer peripheral surface of the cord or a circular convex portion, and the engaging portion in the earphone housing is a concave portion or a groove portion that engages with this. It is also possible.

  8 and 9, an example in which a plurality of engaged portions 73 and a plurality of engaging portions (engaging pieces 51a and 53a) are provided has been described. However, as the engaged portion 73 on the sheath 71 side, an example is provided. Three or more recesses may be provided, and three or more engagement pieces may be formed in the earphone housing accordingly.

  Furthermore, an example in which the engaged portion 73 is not provided in advance on the sheath 71 side is also conceivable. In the earphone housing, an engagement piece is provided as a protrusion to be crimped to the sheath. For example, according to the structure of the embodiment, when the inner lid member 54 is fixed while pressing the cord 70 with the inner lid member 54 after the cord 70 is disposed in the rear casing 51, the rear casing 51 ( Alternatively, the engagement piece also received by the inner lid member 54) crimps the peripheral surface of the sheath 71 and dents a part of the sheath 71, so that the sheath 71 can be used as an engaged portion later on the sheath 71 side. A recess may be formed. Alternatively, in this case, the engagement piece to be crimped may have a sharp pin shape and may penetrate or penetrate the sheath 71.

  In any case, as a structure for preventing the sheath 71 from coming off, it is only necessary to be able to resist the force applied in the longitudinal direction (withdrawal direction) of the cord by the engagement of the engaging portion and the engaged portion.

Various examples of the retaining structure for the core wire 72 are also conceivable.
Even if there are three or more core wires 72, the knotted ball portion M may be made by connecting these three or more core wires together.
Even if there are three or more, the knotted balls abut against the end surface of the sheath 71 even if a force is applied to the core wire 72 in the pulling direction as long as the core wires 72 are arranged on the independent core lines 78. A stop is made.
Note that it is not necessary for all the core wires to be disposed on the independent core line 78. If there are at least two core lines 78 in the sheath 71, even if there are three or more core lines 72, the function of preventing the core lines 72 from being removed can be obtained by forming the knotted portion M. For example, even when two core wires 72 are arranged on each of the two core lines 78 and there are a total of four core wires 72, knots of the four core wires 72 may be made.

10 and 11 show an example in which there is one core line 78. In this case, there is a method in which the separation pin 51b as shown in FIG. 11 is not provided.
For example, the opening 54a is formed in a minimum hole size through which the plurality of core wires 72 can pass. And after passing each core wire 72 through opening 54a, you may make it make the knotted ball part M. FIG.

In the embodiment, an example is described in which a balanced armature unit is used as the acoustic transducer 1 in the earphone housing, but the acoustic transducer 1 may naturally have a configuration that does not use a balanced armature unit.
However, as shown in the embodiment, the sound output hole 27a is provided on the surface (cover body 27) facing the vibration surface of the internal diaphragm 22, and the sound output hole 27a is directly connected to the sound path tube. Arranging the balanced armature unit so as to emit sound to 90 is suitable for downsizing the earphone housing.

In the case of using a balanced armature unit, various forms of the balanced armature unit can be considered. The shape of the audio output hole 27a can be various shapes other than a circle, such as an ellipse, an ellipse, a polygon, and the like.
Various sizes of the audio output holes 27a can be considered. In particular, it is preferable to set a large hole area in consideration of the high-frequency loss.

In the embodiment, the earphone has been described as an example of the acoustic device of the present invention. However, the present invention can be applied not only to the earphone but also to a headphone, a speaker, a microphone, an audio transmitter, a receiver, and the like.
In any acoustic device, the structure for fixing the cord in the housing can be made small without impairing the reliability of the sheath and the core wire.
In particular, the present invention is suitable for an acoustic device in which a small housing is desired, such as a small microphone to be worn on clothes.
In the case of an earphone, the user puts it in his / her ear. Therefore, the present invention has a great effect in terms of improving the wearability by downsizing the housing.

  DESCRIPTION OF SYMBOLS 1 Acoustic converter, 8 Circuit board, 9 Armature, 22 Diaphragm, 26 Case body, 27 Cover body, 27a Audio | voice output hole, 50 Earphone, 51 Rear housing | casing, 51a Engagement piece, 51b Separation pin, 52 Front part Case, 53 earpiece, 54 Inner lid member, 54a Engagement piece, 70 cord, 71 sheath, 72 core wire, 73 engaged portion, 78 core line

Claims (23)

A cord in which a plurality of core wires forming an audio signal transmission path are covered with a sheath;
A housing that houses an acoustic device portion to which the plurality of core wires of the introduced cord are electrically connected;
An engagement portion provided in the housing and engaged with the sheath of the introduced cord;
An engaged device that engages with the engaging portion of the housing provided on the sheath of the cord. The acoustic device according to claim 1, wherein the cord includes a plurality of core wires divided into two or more core lines within the sheath. The cord has a plurality of core wires arranged in one core line in the sheath,
In the casing, the plurality of core wires of the portion where the sheath is peeled off pass through the portion where the paths are separated by the separation structure formed in the casing, and the core wires are connected to each other. The acoustic device according to claim 1, wherein knotting ball portions are formed to bind each other . The acoustic device unit is an acoustic conversion device that outputs sound based on an audio signal transmitted by the code,
The earphone case is provided with an earpiece part to be inserted into a user's ear canal and in which a sound path for guiding the sound output from the acoustic conversion device to the earpiece part is formed. The acoustic device according to any one of 1 to 3. The acoustic device according to claim 4 , wherein the acoustic conversion device is formed of a balanced armature unit. The acoustic device according to claim 2, wherein the engaged portion has a recess formed in a sheath between core lines. The acoustic device according to any one of claims 1 to 3, wherein the sheath has a flat plate shape. The acoustic device according to claim 7, wherein the engaged portion has a concave portion formed on one side of the flat plate shape. The acoustic device according to claim 7, wherein the engaged portion has recesses formed on both sides of the flat plate shape. The acoustic device according to claim 7, wherein the engaged portion is a through hole. The acoustic device according to any one of claims 1 to 3, wherein the sheath has a round shape. The acoustic device according to claim 11, wherein the engaged portion is formed with a concave portion along the circumferential surface of the round shape. The acoustic device according to claim 11, wherein the engaged portion is formed with two concave portions along the peripheral surface of the round shape. The acoustic device according to claim 13, wherein the positions of the two concave portions are formed at symmetrical positions. The acoustic device according to claim 11, wherein the engaged portion is formed with a groove-shaped recess that circulates around the round-shaped peripheral surface. The acoustic device according to claim 4, wherein the engaging portion is located on an opposite side of the earpiece portion with the acoustic device portion interposed therebetween. The acoustic device according to any one of claims 1 to 16, wherein the engagement portion is located in a rear housing that is located behind a housing that houses the acoustic device portion. The said engaging part contains the 1st engaging part which protrudes toward the said acoustic device part, and the 2nd engaging part which protrudes in the direction away from the said acoustic device part side. Sound equipment. The acoustic device according to claim 18, wherein the second engaging portion is provided on an inner lid member. The acoustic device according to claim 17, wherein the cord is accommodated in a space generated by engagement of a housing that houses the acoustic device portion and a rear housing that is located behind the housing. Acoustic device according to any one of claims 1 or 2 or 6 comprising a core retaining structure. It said core retaining structure is an acoustic device according to claim 21 in which the plurality of core wires is turned in knot mating knot ball portion to each other. The acoustic device according to any one of claims 1 to 22, wherein the acoustic device is an earphone.

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