WO2025017959A1 - Earphone - Google Patents

Abstract

[Problem] To provide an earphone which has excellent wearability and which is worn by being securely fit to the ear of a user, and which ensures an excellent volume-feeling and high sound-quality. [Solution] An earphone 1 comprises: an acoustic duct 3 that is made of a hard material and that is inserted into the external auditory canal of an ear; an earphone body 2 that is connected to an end of the acoustic duct 3 on the side thereof opposite the insertion direction; and an elastically deformable ear-ring 4 that is attached to an outer lateral surface of the acoustic duct 3. The length of the acoustic duct 3 on the central axis is 5-13 mm. The ear-ring 4 extends from the outer lateral surface of the acoustic duct 3 so that an angle of inclination with respect to the acoustic duct 3 is 60-100°. The earphone body 2 extends, from the site of connection with the acoustic duct 3, in a direction opposite the ear-ring 4 and at an inclination angle of 50-70° with respect to the acoustic duct 3.

Description

Earphones

The present invention relates to earphones that are worn by inserting an acoustic duct extending from the earphone body into the ear canal of the user's ear.

Normally, sound vibrations transmitted by air conduction are transmitted to the eardrum inside the ear, and the vibrations of the eardrum are transmitted to the cochlea via three ossicles inside the eardrum. The cochlea contains lymphatic fluid, and the vibrations of this lymphatic fluid are converted into electrical signals and transmitted to the auditory nerve, and the brain recognizes these electrical signals as sound.

Earphones worn in the user's ears include air-conduction earphones, which reproduce sound by applying an audio signal to a speaker placed close to the ear and transmit the sound to the eardrum via air conduction. Air-conduction earphones can be broadly divided into two types: in-ear type and in-ear (earplug) type.

Inner-ear type earphones (see, for example, Patent Document 1) are earphones that are used by hooking onto a part of the ear called the concha, which is located at the entrance to the ear. The advantage of inner-ear type earphones is that they do not feel oppressive and make it easy to hear surrounding environmental sounds. In contrast, canal type earphones (see, for example, Patent Document 2) are used by inserting earplug-type earpieces into the ear. The advantage of canal type earphones is that they provide high sound insulation and do not leak sound.

Bone conduction earphones are also known as earphones that allow you to hear surrounding sounds even while wearing them. Bone conduction is a mechanism that omits the process in which vibrations in the air conduction mechanism described above pass through the eardrum and ossicles, and instead transmits sound vibrations directly to the cochlea via the user's skull. Therefore, even if a person with hearing loss has an abnormality in the eardrum or ossicles, as long as the cochlea and auditory nerve are normal, they can still hear sounds reliably through bone conduction. Bone conduction earphones apply this principle.

Various proposals have been made regarding bone conduction earphones. For example, Patent Document 3 proposes a bone conduction earphone that is comfortable to wear, can be made completely waterproof and dustproof, and has a bone conduction microphone whose acoustic characteristics (frequency characteristics) can be partially controlled. Specifically, this bone conduction earphone is composed of a rear cover and an earphone case that houses a bone conduction microphone and a bone conduction speaker and is attached to the rear cover, and a hard resin earplug attached to the earphone case is covered with a sensing cover made of a softer material than the hard resin earplug.

Patent Document 4 also proposes a bone conduction earphone that is unlikely to shift out of position even when the user moves vigorously. This bone conduction earphone is composed of a holder that is inserted into the ear canal and held there, and a device main body, with the device main body having an elastic part that connects the holder to a housing that vibrates due to an electromechanical conversion part. With this bone conduction earphone, when the bone conduction earphone is attached to the user's auricle, the elastic force of the elastic part can press the housing against the inner surface of the intertragic notch, so that the bone conduction earphone is unlikely to shift out of position even when the user moves vigorously.

JP 2006-222492 A JP 2019-145962 A International Publication No. WO2013/118539 JP 2021-175144 A

However, inner-ear earphones have the disadvantage of low sound insulation and a tendency for sound to leak. In contrast, canal-type earphones have the disadvantage that, because the earpieces are inserted deep inside the ear, they put a lot of pressure on the ear and make it difficult to hear surrounding environmental sounds. Therefore, there is a demand for earphones that have high sound insulation, can prevent sound leakage, and do not put pressure on the ears.

In addition, if the diameter of the diaphragm of the speaker housed in the earphone body is increased in order to improve the sound quality of the earphone and ensure high volume and sound quality, the earphone body will become larger. Furthermore, if functions such as a microphone function or noise canceling function are added to the earphone, the battery and circuit board, etc. will become larger, and the earphone body will become larger and heavier. With the structure of conventional earphones, if the earphone body becomes larger or heavier, the earphone will become more likely to fall out of the ear or the pressure on the ear will increase, resulting in a worsening fit for the user.

The present invention was made in consideration of the above problems, and its purpose is to provide earphones that are comfortable to wear and fit securely in the user's ears while ensuring high volume and sound quality.

In order to solve the above problems, the present invention provides earphones that are made of a hard material and include an acoustic duct that is inserted into the ear canal of the ear, an earphone body that is connected to the end of the acoustic duct opposite the insertion direction, and an elastically deformable ear ring that is attached to the outer surface of the acoustic duct, the length of the acoustic duct on the central axis being 5 mm to 13 mm, the ear ring extending from the outer surface of the acoustic duct at an inclination angle of 60° to 100° relative to the acoustic duct, and the earphone body extending from the connection with the acoustic duct in the opposite direction to the ear ring at an inclination angle of 50° to 70° relative to the acoustic duct.

The present invention also provides the above earphone, in which the length of the earphone body along the central axis is 15 mm to 75 mm.

The present invention also provides an earphone in which, when worn, the earring elastically deforms due to the force received when the side of the acoustic duct abuts against the tragus of the ear, pressing against the inner wall of the concha, and the end of the earphone body presses against the cheek due to a moment generated by a reaction force received by the earring from the inner wall of the concha.

The present invention also provides the above-mentioned earphones, in which the earrings are removably attached to the acoustic duct.

The present invention also provides the above earphones, in which the longitudinal length of the earring is 12 to 20 mm.

The present invention also provides the above-mentioned earphones, in which the earring is formed by connecting two rings together.

The present invention also provides the above earphones, in which the acoustic duct is integrally formed with the earphone body.

The present invention also provides the above earphones, in which a speaker is built into the earphone body and is positioned directly above the acoustic duct.

The present invention also provides an earphone, wherein the earphone is an air conduction earphone.

The present invention also provides an earphone, wherein the earphone is a bone conduction earphone.

The present invention also provides the above-mentioned earphones, in which the acoustic duct is equipped with at least one sensor that detects biometric information of the user.

The present invention has the effect of ensuring high volume and sound quality while allowing the earphones to fit securely in the user's ears.

1 is a perspective view of an earphone according to an embodiment of the present invention; 1 is a side view of an earphone according to an embodiment of the present invention. 1 is a plan view of an earphone according to an embodiment of the present invention; FIG. 2 is a bottom view of the earphone according to the embodiment of the present invention. 1 is an exploded partial perspective view showing an earring attachment/detachment structure of an earphone according to one embodiment of the present invention; 1 is a side cross-sectional view of a user's ear showing an earphone being worn according to an embodiment of the present invention; 13 is a diagram showing a substrate incorporated in an earphone according to a modified example of the present invention. FIG. 11 is a cross-sectional view of an acoustic duct of an earphone according to a modified example of the present invention. FIG. 11 is a cross-sectional view of an earphone according to a modified example of the present invention. FIG. 2 is a diagram showing the names of each part of the auricle.

(Embodiment)
An embodiment of the present invention will be described below with reference to the accompanying drawings. Fig. 1 is a perspective view of an earphone 1 according to the present embodiment. Fig. 2 is a side view of the earphone 1 according to the present embodiment. Fig. 3 is a plan view of the earphone 1 according to the present embodiment. Fig. 4 is a bottom view of the earphone 1 according to the present embodiment. Fig. 5 is an exploded partial perspective view showing the attachment/detachment structure of the ear ring of the earphone 1 according to the present embodiment. Fig. 6 is a side cross-sectional view of the user's ear showing the earphone 1 according to the present embodiment being worn.

In the following explanation, the arrow directions in Figures 1 and 2 refer to the "front-to-back" and "up-down" directions, respectively, as shown.

The "up and down" direction is the direction in which the earphone 1 is connected to the user's ear when the user wears the earphone 1 in their ear, in other words, the direction in which the earphone 1 is inserted into or removed from the ear. The direction from the earphone 1 to the user's ear, i.e., the direction in which the earphone 1 is inserted into the ear, is defined as the "down" direction, and the direction from the user's ear to the earphone 1, i.e., the direction in which the earphone 1 is removed from the ear, is defined as the "up" direction.

The "front-to-back" direction is a direction perpendicular to the "up-down" direction, and is the direction connecting the position where the earphone 1 abuts against the tragus of the user's ear and the position where it abuts against the inner wall of the concha when the user wears the earphone 1 in their ear. The direction from the earphone 1 toward the tragus of the ear, i.e., toward the user's cheek, is defined as the "back" direction, and the direction from the earphone 1 toward the inner wall of the concha, i.e., toward the back of the head, is defined as the "front" direction.

Here, FIG. 10 shows the names of each part of the auricle. As shown in FIG. 10, the tragus (also called the tragus) is a protrusion on the face side of the entrance to the ear canal. The outer curved part of the auricle is called the helix. The concha is composed of the cavity of the concha and the velum of the concha shown in FIG. 10. The cavity of the concha is a depression located immediately at the entrance to the ear canal. The velum of the concha is located outside the cavity of the concha when viewed from the entrance to the ear canal, and is a depression separated from the cavity of the concha by a part of the helix. The earphone 1 of the present invention abuts against the inner wall of the velum of the concha. In this specification, the "inner wall of the concha" or "inner wall of the velum of the concha" refers to the wall that forms the edge of the depression that constitutes the concha or the velum of the concha.

As shown in Figs. 1 to 4 and 6, the earphone 1 according to this embodiment includes an acoustic duct 3, an earphone body 2, and an ear ring 4. The earphone 1 according to this embodiment may be a bone conduction earphone or an air conduction earphone, or may be an earphone with both bone conduction and air conduction functions.

The acoustic duct 3 is a rectangular rod-shaped member that is inserted from the external ear canal of the user's ear deeper than the tragus into the ear canal, with its side abutting the tragus of the ear. The acoustic duct 3 is formed to extend diagonally downward from the front end of the lower case 2B of the earphone body 2. Note that in the present invention, the shape of the acoustic duct may be any shape that allows easy insertion from the external ear canal into the ear canal deeper than the tragus, and can be any shape, such as a rod shape, a tube shape, a cylinder shape, or a polygonal prism shape.

The length of the acoustic duct 3 is such that it can be inserted deeper than the tragus into the ear canal of the user's ear. The length from the bottom surface of the earphone body 2 to the tip of the acoustic duct 3 on the central axis of the acoustic duct 3 is not particularly limited as long as it is a length that can introduce speaker sound into the ear canal of the user's ear, but if it is, for example, 5 mm or more, the speaker sound can be reliably introduced into the ear canal of the user's ear. Also, if the length on the central axis of the acoustic duct 3 is, for example, 8 mm or more, the speaker sound can be more reliably introduced into the ear canal of the user's ear. The length on the central axis of the acoustic duct 3 is not particularly limited, but can be, for example, 13 mm or less, which allows the user to feel comfortable wearing without feeling any pressure. Also, if the length on the central axis of the acoustic duct 3 is, for example, 10 mm or less, the user can feel even more comfortable wearing without feeling any pressure.

The length of the acoustic duct in the present invention can be such that it is inserted at least 10 mm or more from the point where it abuts against the tragus in the ear canal of the user's ear. With this length, speaker sound can be reliably introduced into the ear canal of the user's ear when worn on a standard adult's ear. Furthermore, with this length, the acoustic duct abuts firmly against the tragus, so the acoustic duct, ear ring, and earphone body swing like a seesaw to fit and be securely attached to the user's ear.

The acoustic duct 3 may be made of a solid material or a hollow material. For example, if the earphone 1 is a bone conduction earphone, the acoustic duct 3 may be made of a solid material. Also, if the earphone 1 is an air conduction earphone, the acoustic duct 3 may be made of a hollow material.

The earphone body 2 is a long, thin case body connected to the end of the acoustic duct 3 on the opposite side of the insertion direction in the longitudinal direction, and is located outside the ear when the earphone 1 is worn in the ear. The earphone body 2 is formed so as to extend from the connection part with the acoustic duct 3 in the opposite direction to the ear ring 4, that is, toward the rear (see Figures 1 and 2). The earphone body 2 is configured so as to extend toward the rear from the connection part with the acoustic duct 3 at an inclination angle of a predetermined angle θ (see Figure 2) relative to the acoustic duct 3. Therefore, the acoustic duct 3 extends downward from the front end part of the earphone body 2 so as to be inclined diagonally backward by the angle θ. The angle θ can be set to, for example, θ = 60°, but in the present invention, the inclination angle θ is not limited to this and can be set to, for example, 60° ± 10° (50° to 70°).

When the inclination angle θ is within the range of 50° to 70°, for example, when the earphone 1 is worn, the side of the acoustic duct 3 comes into contact with the tragus 11 of the ear, causing the ear ring 4 to elastically deform due to the force F it receives, and presses against the inner wall 13 of the concha. Then, the rear end of the earphone body 2 presses against the cheek 14 due to the moment M generated by the reaction force R1 that the ear ring 4 receives from the inner wall 13 of the concha. The earphone 1 is worn to fit securely in the user's ear, with the tip of the ear ring 4 pressing against the inner wall of the concha and the end of the earphone body 2 pressing against the cheek.

Furthermore, when the tilt angle θ is, for example, 68° or less, the earphone 1 fits more softly when worn. When the tilt angle θ is, for example, 65° or less, the earphone 1 can be fitted even more softly when worn. Furthermore, when the tilt angle θ is, for example, 55° or more, the earphone 1 has the advantage of fitting more tightly when worn and being less likely to fall off. When the tilt angle θ is, for example, 58° or more, the earphone 1 has the advantage of fitting more tightly when worn and being less likely to fall off.

The length of the earphone body 2 on the central axis is not particularly limited as long as it extends from the end of the acoustic duct 3 and can abut against the user's cheek, but if it is at least 15 mm or more, the end of the earphone body 2 presses against the cheek 14 with moderate strength when worn, so that the earphone body can be securely fitted to the user's ear when worn. The length of the earphone body 2 on the central axis is preferably 20 mm or more, so that the end of the earphone body 2 presses against the cheek 14 more strongly when worn, so that the earphone body can be more securely fitted to the user's ear when worn. The length of the earphone body 2 on the central axis is not particularly limited, but if it is, for example, 75 mm or less, the earphone body can be securely fitted to the user's ear without the user feeling a sense of pressure, and a high wearing comfort can be provided. The length of the earphone body 2 on the central axis is preferably 70 mm or less, so that the earphone body can be securely fitted to the user's ear without the user feeling a sense of pressure, and a high wearing comfort can be provided.

The earphone body 2 is formed by joining together an upper case 2A and a lower case 2B. The earphone body 2 houses the speaker 5 (see FIG. 2), as well as a circuit board on which various electronic components are mounted, a battery, and a switch (not shown). The electronic components mounted on the circuit board include an electromagnetic or piezoelectric converter that converts the electrical signal output from the speaker 5 into mechanical vibrations. As shown in FIG. 3, a round multifunction button (command button) 6 is located in the longitudinal center of the top surface of the earphone body 2 (upper case 2A). Also, as shown in FIGS. 1, 2, and 4, a cover 7 is detachably attached to the front of the bottom surface of the earphone body 2 (lower case 2B) to cover an opening (not shown) from below for battery replacement.

As shown in FIG. 2, the speaker 5 is placed directly above the acoustic duct 3 at the front end of the earphone body 2 in a position where it does not come into contact with the user's ear. Because the speaker 5 is placed in such a position, even if the aperture of the speaker 5 is made sufficiently large to improve the sound quality of the speaker 5, the speaker 5 does not get in the way of the ear. Note that in this embodiment, the speaker 5 is housed horizontally along the longitudinal direction within the earphone body 2, but the speaker 5 may also be housed by arranging it perpendicular to the longitudinal direction of the earphone body 2.

The acoustic duct 3 and the earphone body 2 may be formed integrally or separately. By forming the acoustic duct 3 and the earphone body 2 integrally, the strength and rigidity of these components can be increased.

In this embodiment, the earphone body 2 (upper case 2A and lower case 2B) and acoustic duct 3 are made of a hard resin such as ABS resin, which has high rigidity. Note that in the present invention, the earphone body and acoustic duct are not limited to this embodiment and can be made of a hard material. For example, not only ABS resin but also various resins such as polypropylene and polystyrene can be used as the hard material. The acoustic duct may also be made of metal.

The earphone of the present invention is fitted by the earring elastically deforming due to the force received when the side of the acoustic duct abuts against the tragus of the ear, pressing the inner wall of the concha, and the end of the earphone body pressing against the cheek due to the moment generated by the reaction force received by the earring from the inner wall of the concha. Therefore, by making the acoustic duct out of a hard material, the acoustic duct acts as a fitting pillar, allowing the earphone to fit securely and stably. In addition, the acoustic duct in the earphone of the present invention does not need to completely cover the inside of the ear canal, and a gap may be formed between the acoustic duct and the inner wall of the ear canal. Therefore, the earphone of the present invention does not require a component such as an earpiece that is attached to the tip of a canal-type earphone and elastically deforms in order to be inserted deep into the ear and fixed, and therefore can provide a comfortable fit without putting pressure on the ear. In addition, by making the acoustic duct out of a hard material, it is possible to attach a sensor that detects biological information, as in the modified example described below.

The ear ring 4 is attached to the outer surface of the acoustic duct 3 opposite the surface that abuts against the tragus of the ear, and is an elastically deformable member that extends forward (to the left in Figures 1 to 4) from the front surface of the acoustic duct 3. The ear ring 4 is formed so as to extend in the direction opposite to the direction in which the earphone body 2 extends. The ear ring 4 is formed by connecting and integrating two ring-shaped rings 4A and 4B. One of the ear rings 4, ring 4A, is formed so as to abut against the side surface on the front side of the acoustic duct 3 and protrude forward. Ring 4B is formed outside ring 4A and protrudes forward. In this embodiment, rings 4A and 4B are approximately circular, but this is not particularly limited in the present invention, and any shape surrounded by curves or straight lines may be used, for example, an ellipse or a polygon. The ear ring 4 is made by connecting two rings 4A and 4B together, which improves the springiness of the ear ring 4 and allows it to flexibly and elastically deform to fit the shape of the user's ear, making it easy to fit any ear.

The longitudinal length of the ear ring 4, i.e., the length from the part of ring 4A attached to acoustic duct 3 to the tip of ring 4B protruding forward, can be set appropriately depending on the size of the ear, and is not particularly limited, but can be, for example, 12 to 20 mm from the perspective of stability of fit. Furthermore, if the longitudinal length of ear ring 4 is, for example, 13 to 18 mm, the stability of fit can be further improved.

As shown in FIG. 2, the ear ring 4 is attached so as to be parallel to the longitudinal direction of the earphone body 2. Note that in the present invention, the angle at which the ear ring is attached is not limited to this embodiment, and for example, the ear ring can be attached so that the inclination angle with respect to the acoustic duct is 60 to 100 degrees. The angle at which the ear ring is attached can be any angle between an angle that is approximately parallel to the longitudinal direction of the earphone body and an angle that is approximately perpendicular to the acoustic duct.

The earring 4 can be made of any elastically deformable material, such as flexible silicone, elastomer, and rubber.

The ear ring 4 may be detachable from the acoustic duct 3, or may be configured as one piece with the acoustic duct 3. If the ear ring 4 is detachable, multiple types of ear rings of different sizes can be prepared, allowing the user to select the ear ring that best suits the size and shape of their own auricle and ear canal. This allows all users to enjoy a comfortable fit.

An example of the structure for attaching and detaching the ear ring 4 will be described with reference to Figure 5. A semicircular ring-shaped mating protrusion 3A is formed integrally with the upper front surface of the acoustic duct 3, and an engagement projection 3a is integrally formed at the circumferential center of this mating protrusion 3A. In addition, an engagement groove 3b is formed in the vertical direction at the width center of the front surface of the acoustic duct 3, extending linearly downward from the mating protrusion 3A.

On the other hand, one of the rings 4A of the ear ring 4 is formed with a curved (semicircular) mating recess 4a that fits into the mating protrusion 3A formed in the acoustic duct 3, and an engagement groove 4b is formed along the circumferential direction on the inner peripheral surface of this mating recess 4a. At the circumferential center of the engagement groove 4b, a recess (not shown) is formed into which the engagement protrusion 3a protruding from the circumferential center of the mating protrusion 3A is inserted. In addition, an engagement protrusion 4c that engages with the engagement groove 3b formed in the acoustic duct 3 is integrally formed and protrudes from the lower center of the mating recess 4a.

Therefore, the mating recess 4a formed on one ring 4A of the ear ring 4 is fitted into the mating protrusion 3A of the acoustic duct 3, the engagement protrusion 3a protruding from the mating protrusion 3A is engaged with the engagement groove 4b formed on the ear ring 4 (ring 4A), and the engagement protrusion 4c protruding from the ring 4A of the ear ring 4 is engaged with the engagement groove 3b formed on the acoustic duct 3, so that the ear ring 4 is detachably and non-rotatably attached to the upper front side of the acoustic duct 3. In addition, the engagement protrusion 3a protruding from the circumferential center of the mating protrusion 3A is inserted into a recess (not shown) formed in the circumferential center of the engagement groove 4b, thereby improving the non-rotatable strength between the ear ring 4 and the acoustic duct 3. Here, when fitting the ear ring 4A into the acoustic duct 3, the mating position between the acoustic duct 3 and the ear ring 4A can also be determined by engaging the engagement protrusion 4c with the engagement groove 3b.

The position where the earring 4 is attached to the acoustic duct 3 can be any position between the bottom surface of the earphone body 2 and the tip of the acoustic duct 3. On the central axis of the acoustic duct 3, the length from the front end of the earphone body 2 to the earring 4 attachment position and the length from the earring 4 attachment position to the tip of the acoustic duct 3 are not particularly limited, but if they are, for example, 1:9 to 9:1, the earphone 1 can be securely fitted and worn in the user's ear. In the acoustic duct 3, the length from the front end of the earphone body 2 to the earring 4 attachment position and the length from the earring 4 attachment position to the tip of the acoustic duct 3 are preferably 2:3 to 2:5, which allows the earphone 1 to be more securely fitted and worn in the user's ear.

The above describes the configuration of the earphone 1 that is worn in one ear (left or right) of the user, but as the configuration of the earphone 1 worn in the other ear (right or left) is exactly the same as or symmetrical to that of the other, illustrations and descriptions thereof are omitted. If the configurations of the earphones worn in the left and right ears are exactly the same without distinction between left and right, the user can wear both earphones in either the left or right ear without distinction between left and right, which increases user convenience.

Here, FIG. 6 shows the state in which the earphone 1 according to this embodiment is worn in the user's ear. The earphone 1 is worn in a direction in which the rear surface of the acoustic duct 3 abuts against the tragus 11 (tragus) of the ear. That is, the earphone 1 is worn in the user's ear by inserting the acoustic duct 3 into the ear canal 12 of the ear, and at this time, the rear surface of the acoustic duct 3 abuts against the tragus 11 of the ear. Then, the acoustic duct 3 is pressed by the tragus 11, so that the ear ring 4 attached to the acoustic duct 3 is pressed against the inner wall 13 of the concha, more specifically, the inner wall of the concha, and bends due to elastic deformation as shown in FIG. 6. In this case, the ear ring 4 is configured by connecting and integrating two rings 4A and 4B, so it easily elastically deforms and is pressed against the inner wall 13 of the concha.

Next, in the X-Y coordinate plane in Figure 6, with the left-right direction (front-back direction) as the X axis and the up-down direction as the Y axis, the forces acting on the earphone 1 and the moments generated by these forces can be analyzed as follows. Note that the point where the rear surface of the acoustic duct 3 abuts against the tragus 11 of the ear is designated as a, the point where the earring 4 abuts against the inner wall 13 of the concha is designated as b, and the point where the earphone body 2 abuts against the cheek is designated as c.

When the earphone 1 is worn, an external force F is applied from the tragus 11 of the user's ear to point a on the rear surface of the acoustic duct 3 of the earphone 1. The application of external force F pushes the ear ring 4 forward and strikes point b on the inner wall 13 of the concha, compressing the ear ring 4 between the acoustic duct 3 and the inner wall 13. This causes the ear ring 4 to elastically deform and bend into an arc as shown in FIG. 6, and receives a reaction force (resistance) R1 from the inner wall 13 of the concha at point b. This reaction force R1 then generates a moment M in the earphone 1 in the direction of the arrow (clockwise), and the earphone body 2 of the earphone 1 that receives this moment M has its rear end abut against the user's cheek 14 at point c, and receives an upward reaction force (reaction force) R2 from the cheek 14.

Here, the X-axis components Fx, R1x, and R2x of the external force F and the two reaction forces R1 and R2 are respectively expressed by the following equations.
Fx = F sinθ
R1x=R1・sinθ
R2x = 0
As shown in the above equation, the X-axis component of the reaction force R2 is R2x = 0, so
F=R1
holds true.

Furthermore, the Y-axis components Fy, R1y, and R2y of the external force F and the two reaction forces R1 and R2 are expressed by the following equations, respectively.
Fy = F cosθ
R1y=R1・cosθ
R2y = R2

Here, if the distance in the X-axis direction between points a and b is L1, and the distance in the X-axis direction between points a and c is L2, and the balance of the moment is considered, the following equation is established.
R1y・L1=R2・L2…(1)

Therefore, the reaction force R2 that the earphone main body 2 (lower case 2B) of the earphone 1 receives from the user's cheek 14 can be calculated from the above equation (1) as follows:
R2=R1y・(L1/L2)
=R1・cosθ・(L1/L2)
=F・cosθ・(L1/L2)…(2)

Therefore, according to the principle of action and reaction, the user's cheek 14 receives a pressure force P from the earphone 1 at point c that is equal to but opposite in direction to the reaction force R2 expressed by equation (2).

The user then receives a pressing force Q at point b that is equal in magnitude to but opposite in direction to the reaction force R1 acting on the inner wall 13 of the concha. In this way, the earphone 1 worn in the user's ear presses the inner wall 13 of the user's concha with pressing force Q at point b, and presses the user's cheek 14 with pressing force P at point c, so that the earphone 1 fits securely in the user's ear, improving its wearability. Variations in the size and shape of the user's concha and ear canal 12 are absorbed by the elastic deformation of the ear ring 4, so that the earphone 1 can be worn with high wearability for any user, and will not easily come off and fall out of the ear, even if the user moves vigorously.

As explained above, when wearing the earphone 1 of this embodiment, the force F received when the side of the acoustic duct 3 comes into contact with the tragus 11 of the ear causes the ear ring 4 to elastically deform and press against the inner wall 13 of the concha, more specifically, the inner wall of the concha. Then, the moment M generated by the reaction force R1 received by the ear ring 4 from the inner wall 13 of the concha causes the rear end of the earphone body 2 to press against the cheek 14. The earphone 1 is securely fitted and worn in the user's ear by the tip of the ear ring 4 pressing against the inner wall of the concha and the end of the earphone body 2 pressing against the cheek.

As such, unlike conventional earplug-type earphones that are worn by inserting earpieces attached to acoustic ducts into the ears, the earphones 1 of this embodiment do not put pressure on the inner walls of the ear canal with the acoustic duct 3. For this reason, the acoustic duct 3 can be made of a hard material and its thickness can be made thinner than the ear canal. This allows the user to achieve a comfortable fit without feeling any pressure.

When the earphone 1 of this embodiment is a bone conduction earphone, when the earphone 1 is fitted to the left and right auricles 10 of the user and worn, the electrical signal of the sound (speaker sound) emitted from the speaker 5 is converted into mechanical vibration by a converter (not shown) built into the earphone body 2. The mechanical vibration is conducted to the bone near the user's ear via the acoustic duct 3, vibrating the bone. The bone vibration is then transmitted to the cochlea, and the vibration of the lymph fluid in the cochlea is converted into an electrical signal and transmitted to the auditory nerve, and the brain recognizes this electrical signal as sound. Therefore, even if a person with hearing loss has an abnormality in the eardrum or ossicles, as long as the cochlea and auditory nerve are normal, they can reliably hear the sound through this bone conduction. In the earphone 1 of this embodiment, the vibration from the speaker 5 is transmitted directly to the user's bone via the acoustic duct 3 inserted into the ear canal 12, so a high sense of volume and sound quality can be obtained. That is, in this embodiment, the acoustic duct 3 is inserted into the ear canal 12 of the user's ear, and the acoustic duct 3 is made of a hard resin with high rigidity (e.g., ABS resin), so that the vibrations caused by the speaker sound are transmitted directly and efficiently to the bones around the user's ear without attenuation, resulting in a high sense of volume and sound quality.

If the earphone 1 of this embodiment is an air conduction earphone, a communication passage may be formed in the acoustic duct 3 of the earphone 1 to connect the speaker 5 to the ear canal of the ear. The speaker sound is introduced into the ear canal of the user's ear through this communication passage and is transmitted to the cochlea via the eardrum. With the earphone 1 of this embodiment, the speaker sound is reliably introduced into the ear canal, allowing the speaker sound to be heard clearly even in places with loud environmental sounds, and preventing touch noise and the user's own voice from resonating.

As a result, according to the earphone 1 of this embodiment, when a user wears the earphone, the side of the acoustic duct comes into contact with the tragus of the ear, which presses against the acoustic duct, and the ear ring elastically deforms due to the force received by the acoustic duct and comes into contact with the inner wall of the concha, more specifically, the inner wall of the concha, pressing against the inner wall. The ear ring then receives a reaction force from the inner wall of the concha, more specifically, the inner wall of the concha. The moment generated by this reaction force causes the longitudinal end of the earphone body to come into contact with the user's cheek, pressing against the cheek and receiving a reaction force from the cheek. Therefore, the earphone of this embodiment presses against the inner wall of the concha and the cheek with a pressing force that is equal in magnitude to the two reaction forces but in the opposite direction, according to the principle of action and reaction. As a result, even earphones that use a configuration in which an acoustic duct is inserted into the ear canal can be securely worn in a state that fits the user's ear, improving the comfort of wearing them.

The earphone 1 of this embodiment can also be called a "seesaw-type earphone" because the entire earphone can swing like a seesaw around the point where the tragus of the acoustic duct abuts (point a in Figure 6).

As described above, the earphone 1 of this embodiment is fitted by swinging like a seesaw, so even if the earphone body becomes larger or heavier, it can be fitted securely without feeling any pressure on the ear. This makes it possible to increase the diameter of the speaker's diaphragm to improve sound quality, or to increase the size of the battery and circuit board by adding various functions.

Furthermore, with the earphone 1 of this embodiment, one side of the acoustic duct only needs to come into contact with the tragus of the ear, and there is no need to stabilize the earphone solely with an earpiece that is inserted into the ear canal as with conventional canal-type earphones, so the feeling of pressure on the ear can be reduced.

Furthermore, with the earphone 1 of this embodiment, the acoustic duct is inserted deeper than the tragus into the ear canal, so sound vibrations can be reliably introduced into the ear canal. For example, if the earphone of the present invention is a bone conduction earphone, vibrations from the speaker are transmitted directly and efficiently to the user's bones via the acoustic duct inserted into the ear canal, resulting in a high sense of volume and sound quality.

(Modification)
Next, a modified example of the above-mentioned embodiment will be described with reference to Figs. 7 to 9. Fig. 7 is a diagram showing a substrate incorporated in an earphone according to a modified example of the present invention. Fig. 8 is a cross-sectional view of an acoustic duct of an earphone according to a modified example of the present invention. Fig. 9 is a cross-sectional view of an earphone according to a modified example of the present invention. Note that in the following description of this modified example, only configurations that differ from the above-mentioned embodiment will be described, and descriptions of common parts will be omitted.

This modified example differs from the above-described embodiment in that the acoustic duct 3 is equipped with at least one sensor that detects the user's biometric information. In other words, the earphones of this modified example also function as a device for measuring the user's biometric information. In this specification, "biometric information" means information related to the state of a living organism, and more specifically, information related to the health and exercise state of the living organism. Biometric information detected by the present invention is not limited to, but includes, for example, pulse rate, heart rate, blood oxygen saturation (SpO2), blood pressure, blood flow, HRV analysis (stress level), vascular age, head tilt, activity level, body temperature, and ear temperature.

In this modification, the acoustic duct 3 has a function of detecting the user's biological information in addition to the function of introducing speaker sound into the user's ear canal. In this modification, the acoustic duct 3 has a pulse sensor (HR sensor) 8 and a temperature sensor 9. In this modification, as shown in Figures 7 to 9, the acoustic duct 3 incorporates a board 10 on which the pulse sensor 8 and temperature sensor 9 are mounted. The pulse sensor 8 and temperature sensor 9 are attached so as to be exposed on the surface of the acoustic duct 3 that abuts against the tragus, and when worn, they come into contact with the skin behind the tragus in the ear canal. The board 10 is not particularly limited, but can be a deformable board, for example a flexible printed circuit board (FPC).

The pulse sensor 8 is a reflective pulse wave sensor that detects the pulse rate and blood oxygen saturation (SpO2), etc., by shining light of a specific wavelength onto the skin inside the ear canal and measuring the reflected light.

The temperature sensor 9 is a sensor that has a thermal contact type temperature detection element such as a thermistor and detects the skin temperature, i.e., body temperature, by contacting the skin in the ear canal.

In the present invention, the sensor equipped in the acoustic duct is not particularly limited as long as it is a sensor capable of acquiring biometric information of the user, and can be, for example, a pulse sensor, a temperature sensor, a body temperature sensor, an acceleration sensor, a gyro sensor, a nine-axis sensor, a blood pressure measurement sensor, etc.

In the present invention, the sensor provided in the acoustic duct is not limited to a sensor that contacts the skin in the ear canal and obtains biological information through the skin, but may be a sensor that obtains biological information without contacting the skin in the ear canal. For example, the sensor provided in the acoustic duct may be a non-contact temperature sensor that measures surface temperature using infrared rays or the like.

The earphones of the present invention may also be equipped with an acceleration sensor to obtain biometric information such as the user's head tilt (posture) and movement state.

The earphone 1 of this modified example has two sensors, a pulse sensor 8 and a temperature sensor 9, but the earphone of the present invention is not limited to this and may have only one sensor, or three or more sensors. Furthermore, the earphone of the present invention may measure one or multiple pieces of biological information.

The earphone 1 of this modified example measures biometric information inside the ear canal, so when measuring pulse waves using a reflective pulse wave sensor such as an HR sensor, it is not affected by sunlight or other factors, and biometric information can be obtained stably.

The main body 2 of the earphone 1 of this modified example may house a board connected to the board 10 built into the acoustic duct 3, or the board may be formed integrally with the board 10. The electronic components mounted on the board in the main body 2 include an A/D converter that converts the analog signals detected by the pulse sensor 8 and the body temperature sensor 9 into digital signals, a storage means that temporarily stores the converted digital signals, and a communication means that transmits the measured data to an external terminal, etc.

The earphone 1 according to this modified example fits securely in the user's ear without causing the user to feel any pressure, which has the effect of allowing the user's biometric information to be measured accurately.

The earphones of the present invention may be arranged so that, for example, the earphone worn in one ear further functions as a bioinformation measuring device as in the above-mentioned modified example, and the earphone worn in the other ear only functions as an earphone. This makes it possible to wear an earphone with the function of a bioinformation measuring device and an earphone with only earphone function in each of the left and right ears, and to measure bioinformation in one ear while enjoying music or the like with both ears.

Furthermore, the earphones of the present invention may be configured so that the earphone worn in one ear is equipped with a pulse sensor and a body temperature sensor, and the earphone worn in the other ear is equipped with an acceleration sensor. This makes it possible to enjoy music or the like with both ears while measuring different biological information with each ear.

Conventionally, wristwatch-type biometric measuring devices worn on the user's wrist are known as devices for measuring biometric information. However, wristwatch-type biometric measuring devices are prone to generating noise when the user moves their hand during training and in daily life. In addition, wristwatch-type devices are unable to completely block out external light, resulting in low accuracy of the light sensor.

In contrast, the earphones of the present invention are worn with the entire earphones swinging like a seesaw around the point where the tragus of the acoustic duct, which serves as the measuring part, comes into contact (point a in Figure 6). When the earphones of the present invention are worn as described above, the side of the acoustic duct comes into close contact with the surface of the tragus side inside the user's ear canal. Because the tragus is highly elastic, there is very good adhesion between the side of the acoustic duct and the skin on the tragus side inside the ear canal. Because the tragus has many capillaries and the skin is thin, the sensor of the acoustic duct comes into close contact with this part, allowing accurate measurement of biological information such as pulse rate.

In addition, because the earphones of the present invention measure biometric information inside the ear canal, they are able to block external light compared to conventional wristwatch-type earphones, and can improve accuracy even when using optical sensors. In addition, because there is less movement inside the ear than inside the arm, noise caused by movement is less likely to occur. Therefore, the earphones of the present invention can accurately measure biometric information even while the user is active during training and in daily life.

In addition, the earphones of the present invention have sensors in an acoustic duct that is long enough to be inserted into the ear canal, so multiple sensors can be placed along the length of the acoustic duct.

In addition, the portion that functions as the biometric information measuring device in the present invention can be attached to other types of earphones in addition to the earphones of the present invention. In other words, the sensor that detects the user's biometric information in the present invention can be attached to the acoustic duct of any earphone, not limited to the earphones of the present invention, to make it an earphone that can detect biometric information within the ear canal.

The present invention is not limited to the embodiments described above, and various modifications are possible within the scope of the claims and the technical ideas described in the specification and drawings.

1: Earphone, 2: Earphone body, 2A: Upper case, 2B: Lower case,
3: acoustic duct, 3A: fitting protrusion of acoustic duct, 3a: engagement protrusion of acoustic duct,
3b: Acoustic duct engagement groove, 4: Ear ring, 4A, 4B: Ring,
4a: Ring fitting recess, 4b: Ring engagement groove, 4c: Ring engagement protrusion,
5: Speaker, 6: Multifunction button, 7: Cover, 11: Tragus, 12: External auditory canal, 13: Inner wall of the concha, 14: Cheek

Claims (11)

An acoustic duct made of a hard material and inserted into the ear canal;
An earphone body connected to an end of the acoustic duct opposite to an insertion direction thereof;
and an elastically deformable ear ring attached to an outer surface of the acoustic duct,
The length of the acoustic duct on the central axis is 5 mm to 13 mm;
The ear ring extends from an outer surface of the acoustic duct at an inclination angle of 60 to 100 degrees with respect to the acoustic duct,
The earphone body extends from a connection portion with the acoustic duct in a direction opposite to the ear ring at an inclination angle of 50° to 70° with respect to the acoustic duct. The earphone according to claim 1, wherein the length of the earphone body on the central axis is 15 mm to 75 mm. The earphone according to claim 1 or 2, wherein, when worn, the earring elastically deforms due to the force received when the side of the acoustic duct abuts against the tragus of the ear, pressing against the inner wall of the concha, and the end of the earphone body presses against the cheek due to a moment generated by a reaction force received by the earring from the inner wall of the concha. The earphone according to claim 1 or 2, wherein the earring is removably attached to the acoustic duct. The earphone according to claim 1 or 2, wherein the longitudinal length of the earring is 12 to 20 mm. The earphone according to claim 1 or 2, wherein the earring is formed by connecting two rings together. The earphone according to claim 1 or 2, wherein the acoustic duct is integrally formed with the earphone body. The earphone body has a built-in speaker,
The earphone according to claim 1 or 2, wherein the speaker is disposed directly above the acoustic duct. The earphone according to claim 1 or 2, which is an air conduction earphone. The earphone according to claim 1 or 2, which is a bone conduction earphone. The earphone according to claim 1 or 2, wherein the acoustic duct is equipped with at least one sensor that detects biometric information of the user.