Earphone

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

[0001] The present invention relates to an earphone that is worn by inserting an acoustic duct extending from the earphone body into the ear canal of a user's ear.

[0002] 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 lymph, and the vibrations of this lymph are converted into electrical signals and transmitted to the auditory nerve, which the brain recognizes as sound.

[0003] Air-conduction earphones are earphones worn in the user's ears that 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: inner-ear type and in-ear (earplug) type.

[0004] 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. Inner-ear type earphones have the advantage of not feeling any pressure and making 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. Canal type earphones have the advantage of providing high sound insulation and preventing sound leakage.

[0005] Bone conduction earphones are also known as earphones that allow users to hear surrounding sounds while wearing them. Bone conduction eliminates the process in which vibrations pass through the eardrum and ossicles in the air conduction mechanism described above, and instead transmits sound vibrations directly to the cochlea via the user's skull. Therefore, even if a person with hearing loss has abnormalities 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.

[0006] Various proposals have been made regarding bone conduction earphones. For example, Patent Document 3 proposes a bone conduction earphone that is comfortable to wear, has a completely waterproof and dustproof structure, and allows for partial control of the acoustic characteristics (frequency characteristics) of the bone conduction microphone. Specifically, this bone conduction earphone is composed of a rear cover and an earphone case that houses the bone conduction microphone and bone conduction speaker and is attached to the rear cover. A hard resin earplug provided in the earphone case is covered with a sensing cover made of a softer material than the hard resin earplug.

[0007] Furthermore, Patent Document 4 proposes a bone conduction earphone that is less likely to shift out of position even during vigorous physical movements. This bone conduction earphone is composed of a holder that is inserted into and held in the ear canal, and a device main body, and the device main body has 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 the bone conduction earphone is less likely to shift out of position even during vigorous physical movements.

[0008] Japanese Patent Application Laid-Open No. 2006-222492 Japanese Patent Application Laid-Open No. 2019-145962 International Publication No. WO2013 / 118539 Japanese Patent Application Laid-Open No. 2021-175144

[0009] However, inner-ear earphones have the disadvantage of low sound insulation and prone to sound leakage. In contrast, canal-type earphones have the disadvantage of placing earpieces deep in the ear, which creates a strong sense of pressure on the ear and makes 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 cause a sense of pressure on the ear.

[0010] Furthermore, if the diameter of the diaphragm of the speaker housed in the earphone body is increased 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 or noise canceling function are added to the earphone, the battery and circuit board will become larger, and the earphone body will become larger and heavier. With conventional earphone structures, if the earphone body becomes larger or heavier, the earphone will easily fall out of the ear or the pressure on the ear will increase, resulting in a worsening fit for the user.

[0011] The present invention has been made in consideration of the above problems, and its purpose is to provide earphones that are comfortable to wear and that fit securely in the user's ears while ensuring high volume and sound quality.

[0012] In order to solve the above-mentioned problems, the present invention provides earphones comprising an acoustic duct made of a hard material and inserted into the ear canal of the ear, an earphone main body connected to the end of the acoustic duct opposite the insertion direction, and an elastically deformable ear ring attached to the outer surface of the acoustic duct, wherein the length of the acoustic duct on the central axis is 5 mm to 13 mm, the ear ring extends from the outer surface of the acoustic duct so that the inclination angle to the acoustic duct is 60 to 100 degrees, and the earphone main body extends from the connecting part with the acoustic duct in the opposite direction to the ear ring at an inclination angle of 50 to 70 degrees to the acoustic duct.

[0013] The present invention also provides the above earphone, wherein the length of the earphone body along the central axis is 15 mm to 75 mm.

[0014] The present invention also provides earphones 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 the reaction force received by the earring from the inner wall of the concha.

[0015] The present invention also provides the above earphone, wherein the ear ring is detachably attached to the acoustic duct.

[0016] The present invention also provides the above earphone, wherein the length of the ear ring in the longitudinal direction is 12 to 20 mm.

[0017] The present invention also provides the above-mentioned earphone, wherein the ear ring is configured by connecting two rings together.

[0018] The present invention also provides the above-mentioned earphone, wherein the acoustic duct is integrally formed with the earphone body.

[0019] The present invention also provides the above-mentioned earphone, wherein a speaker is built into the earphone body and is disposed directly above the acoustic duct.

[0020] The present invention also provides an earphone, wherein the earphone is an air conduction earphone.

[0021] The present invention also provides an earphone, wherein the earphone is a bone conduction earphone.

[0022] The present invention also provides the above-mentioned earphone, wherein the acoustic duct is provided with at least one sensor that detects biological information of the user.

[0023] According to the present invention, it is possible to obtain the effect that earphones can be worn in a secure fit in the user's ears while ensuring high volume and sound quality.

[0024] FIG. 1 is a perspective view of an earphone according to an embodiment of the present invention. FIG. 2 is a side view of an earphone according to an embodiment of the present invention. FIG. 3 is a plan view of an earphone according to an embodiment of the present invention. FIG. 4 is a bottom view of an earphone according to an embodiment of the present invention. FIG. 5 is an exploded partial perspective view showing the earring attachment / detachment structure of an earphone according to an embodiment of the present invention. FIG. 6 is a side cross-sectional view of a user's ear showing how an earphone according to an embodiment of the present invention is worn. FIG. 7 is a diagram showing a substrate incorporated into 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. FIG. 10 is a diagram showing the names of each part of the auricle.

[0025] (Embodiments) An embodiment of the present invention will now be described with reference to the accompanying drawings. Fig. 1 is a perspective view of an earphone 1 according to this embodiment. Fig. 2 is a side view of the earphone 1 according to this embodiment. Fig. 3 is a plan view of the earphone 1 according to this embodiment. Fig. 4 is a bottom view of the earphone 1 according to this embodiment. Fig. 5 is an exploded partial perspective view showing the earring attachment / detachment structure of the earphone 1 according to this embodiment. Fig. 6 is a side cross-sectional view of the user's ear showing the earphone 1 according to this embodiment being worn.

[0026] In the following description, the directions of the arrows in FIGS. 1 and 2 are the "front-rear" and "up-down" directions, respectively, as shown.

[0027] The "up and down" direction is the direction in which the earphone 1 connects with 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 toward 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 toward the earphone 1, i.e., the direction in which the earphone 1 is removed from the ear, is defined as the "up" direction.

[0028] 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 is wearing the earphone 1 in their ear. The direction from the earphone 1 toward the tragus of the ear, i.e., the direction 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., the direction toward the back of the head, is defined as the "front" direction.

[0029] 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 curved outer part of the auricle is called the helix. The concha is composed of the cavity of the concha and the vestibulum of the concha, as shown in FIG. 10. The cavity of the concha is a depression located immediately at the entrance to the ear canal. The vestibulum 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 part of the helix. The earphone 1 of the present invention abuts against the inner wall of the vestibulum of the concha. In this specification, the "inner wall of the concha" or "inner wall of the vestibulum of the concha" refers to the wall that forms the edge of the depression that makes up the concha or vestibulum of the concha.

[0030] 1 to 4 and 6, the earphone 1 according to this embodiment includes an acoustic duct 3, an earphone main 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 that has both bone conduction and air conduction functions.

[0031] The acoustic duct 3 is a rectangular rod-shaped member that is inserted from the external auditory canal of the user's ear to a depth deeper than the tragus, with its side surface abutting against the tragus. 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 acoustic duct may have any shape that allows for easy insertion from the external auditory canal to a depth deeper than the tragus, and may have any shape, such as a rod shape, a tube shape, a cylindrical shape, or a polygonal prism shape.

[0032] 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 of the earphone body 2 to the tip of the acoustic duct 3 along the central axis of the acoustic duct 3 is not particularly limited as long as it is long enough to introduce speaker sound into the ear canal of the user's ear. For example, a length of 5 mm or more can reliably introduce speaker sound into the ear canal of the user's ear. Furthermore, a length of 8 mm or more along the central axis of the acoustic duct 3 can more reliably introduce speaker sound into the ear canal of the user's ear. The length of the acoustic duct 3 along the central axis is not particularly limited, but can be, for example, 13 mm or less, which can provide a comfortable fit without causing the user to feel any pressure. Furthermore, a length of 10 mm or less along the central axis of the acoustic duct 3 can provide a more comfortable fit without causing the user to feel any pressure.

[0033] The length of the acoustic duct in the present invention can be at least 10 mm deep from the point where it contacts the tragus in the ear canal of the user's ear. This length ensures that speaker sound can be reliably introduced into the ear canal of a standard adult's ear when the earphone is worn. Furthermore, this length allows the acoustic duct to contact the tragus firmly, allowing the acoustic duct, earring, and earphone body to swing like a seesaw, ensuring a secure fit around the user's ear.

[0034] 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.

[0035] The earphone main body 2 is a long, thin case body connected to the end of the acoustic duct 3 on the opposite side of the longitudinal direction of the earphone 1 relative to the insertion direction, and is positioned outside the ear when the earphone 1 is worn in the ear. The earphone main body 2 is formed so as to extend from the connecting portion with the acoustic duct 3 in the direction opposite the earring 4, i.e., toward the rear (see FIGS. 1 and 2). The earphone main body 2 is configured so as to extend from the connecting portion with the acoustic duct 3 toward the rear at a predetermined angle θ (see FIG. 2) relative to the acoustic duct 3. Therefore, the acoustic duct 3 extends downward and obliquely rearward from the front end of the earphone main body 2 at an angle θ. The angle θ can be set to, for example, θ = 60°, but in the present invention, the angle θ is not limited to this and can be set to, for example, 60° ± 10° (50° to 70°).

[0036] When the inclination angle θ is within a range of 50° to 70°, for example, when the earphone 1 is worn, the ear ring 4 elastically deforms due to a force F received when the side of the acoustic duct 3 abuts against the tragus 11 of the ear, and presses against the inner wall 13 of the concha. Then, a moment M generated by a reaction force R1 received by the ear ring 4 from the inner wall 13 of the concha causes the rear end of the earphone main body 2 to press against the cheek 14. The earphone 1 fits securely in the user's ear when worn, with the tip of the ear ring 4 pressing against the inner wall of the concha and the end of the earphone main body 2 pressing against the cheek.

[0037] Furthermore, when the tilt angle θ is, for example, 68° or less, the earphones 1 fit more softly when worn. When the tilt angle θ is, for example, 65° or less, the earphones 1 can be worn even more softly. When the tilt angle θ is, for example, 55° or more, the earphones 1 have the advantage of fitting tightly and being less likely to fall out. When the tilt angle θ is, for example, 58° or more, the earphones 1 have the advantage of fitting tightly and being less likely to fall out.

[0038] The length of the earphone body 2 along 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. However, if it is at least 15 mm or more, the end of the earphone body 2 presses against the cheek 14 with an appropriate amount of pressure when worn, allowing the earphone to fit securely in the user's ear. The length of the earphone body 2 along the central axis is preferably 20 mm or more, which allows the end of the earphone body 2 to press more firmly against the cheek 14 when worn, allowing the earphone to fit securely in the user's ear. The length of the earphone body 2 along the central axis is also not particularly limited, but if it is 75 mm or less, the earphone body 2 will fit securely in the user's ear without causing a feeling of pressure, providing a comfortable fit. The length of the earphone body 2 along the central axis is preferably 70 mm or less, which allows the earphone body 2 to fit securely in the user's ear without causing a feeling of pressure, providing a comfortable fit.

[0039] The earphone main body 2 is formed by joining an upper case 2A and a lower case 2B together. The earphone main body 2 houses a speaker 5 (see FIG. 2 ), a circuit board mounted with various electronic components, a battery, and a switch (not shown). The electronic components mounted on the circuit board include an electromagnetic or piezoelectric transducer that converts the electrical signal output from the speaker 5 into mechanical vibration. As shown in FIG. 3 , a round multi-function button (command button) 6 is located in the longitudinal center of the top surface of the earphone main body 2 (upper case 2A). Additionally, as shown in FIGS. 1 , 2 , and 4 , a cover 7 is detachably attached to the front of the bottom surface of the earphone main body 2 (lower case 2B) to cover an opening (not shown) for battery replacement from below.

[0040] 2, the speaker 5 is located at the front end of the earphone body 2, directly above the acoustic duct 3, in a position where it does not come into contact with the user's ear. Because the speaker 5 is located in this position, even if the diameter of the speaker 5 is made large enough to improve the sound quality of the speaker 5, the speaker 5 will 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 vertically relative to the longitudinal direction of the earphone body 2.

[0041] The acoustic duct 3 and the earphone main body 2 may be formed integrally or separately. By forming the acoustic duct 3 and the earphone main body 2 integrally, the strength and rigidity of these components can be increased.

[0042] In this embodiment, the earphone body 2 (upper case 2A and lower case 2B) and the 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 the acoustic duct are not limited to this embodiment and can be made of any hard material. For example, the hard material can be not only ABS resin, but also various other resins such as polypropylene and polystyrene. The acoustic duct may also be made of metal.

[0043] The earphone of the present invention is fitted by elastically deforming the earring 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 then by the moment generated by the reaction force received by the earring from the inner wall of the concha, pressing the end of the earphone body against the cheek. Therefore, by making the acoustic duct out of a hard material, the acoustic duct acts as a support for fitting, ensuring a secure fit and stable fit around the ear. Furthermore, the acoustic duct in the earphone of the present invention does not need to completely cover 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 elastically deforming earpiece attached to the tip of a canal-type earphone to be inserted deep into the ear and fixed, thereby providing a comfortable fit without pressuring the ear. Furthermore, 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.

[0044] 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 FIGS. 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 extension direction of the earphone main body 2. The ear ring 4 is composed of two ring-shaped rings 4A and 4B that are connected together as a single unit. One of the ear rings, ring 4A, abuts against the side surface on the front side of the acoustic duct 3 and is formed so as to protrude forward. Ring 4B is formed outside ring 4A and protrudes forward. Note that, while in this embodiment, rings 4A and 4B are substantially circular, this is not particularly limited in the present invention and may be any shape surrounded by curves or straight lines, such as an ellipse or a polygon. The ear ring 4 is constructed 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.

[0045] 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 wearing stability. Furthermore, if the longitudinal length of ear ring 4 is, for example, 13 to 18 mm, wearing stability can be further improved.

[0046] As shown in Figure 2, the ear rings 4 are attached so that they are parallel to the longitudinal direction of the earphone body 2. Note that in the present invention, the angle at which the ear rings are attached is not limited to this embodiment, and they can be attached so that their inclination angle with respect to the acoustic duct is, for example, 60 to 100 degrees. Furthermore, the angle at which the ear rings are 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.

[0047] The ear ring 4 can be made of any elastically deformable material, such as soft silicone, elastomer, rubber, and the like.

[0048] The ear rings 4 may be detachable from the acoustic duct 3, or may be integral with the acoustic duct 3. If the ear rings 4 are 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 ensures a high level of wearing comfort for all users.

[0049] 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 integrally formed on the upper front side of the acoustic duct 3, and an engagement projection 3a is integrally formed at the circumferential center of this mating protrusion 3A. Furthermore, an engagement groove 3b is formed in the vertical direction at the center of the width of the front side of the acoustic duct 3, extending linearly downward from the mating protrusion 3A.

[0050] On the other hand, one ring 4A of the ear ring 4 is formed with a fitting recess 4a having a concave curved surface (semicircular) that fits into the fitting protrusion 3A formed on the acoustic duct 3, and an engagement groove 4b is formed in the inner peripheral surface of this fitting recess 4a along the circumferential direction. 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 fitting protrusion 3A is inserted. Furthermore, an engagement protrusion 4c that engages with the engagement groove 3b formed on the acoustic duct 3 is integrally formed at the lower center of the fitting recess 4a.

[0051] Therefore, the ear ring 4 is detachably and non-rotatably attached to the upper front side of the acoustic duct 3 by fitting the mating recess 4a formed on one ring 4A of the ear ring 4 into the mating protrusion 3A of the acoustic duct 3, engaging the engagement protrusion 3a protruding from the mating protrusion 3A with the engagement groove 4b formed on the ear ring 4 (ring 4A), and engaging the engagement protrusion 4c protruding from the ring 4A of the ear ring 4 with the engagement groove 3b formed on the acoustic duct 3. Furthermore, 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.

[0052] The position at which the earring 4 is attached to the acoustic duct 3 can be any position between the bottom surface of the earphone main 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 main 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 for example, a ratio of 1:9 to 9:1 allows the earphone 1 to be securely fitted and worn in the user's ear. In the acoustic duct 3, the ratio of the length from the front end of the earphone main 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 is preferably 2:3 to 2:5, which allows the earphone 1 to be securely fitted and worn in the user's ear.

[0053] While the above has described the configuration of the earphone 1 worn in one ear (left or right) of the user, the configuration of the earphone 1 worn in the other ear (left or right) is exactly the same as or symmetrical to that of the other, and therefore illustrations and descriptions thereof will be omitted. If the configurations of the earphones worn in the left and right ears are exactly the same regardless of left or right, the user can wear both earphones in either the left or right ear without distinguishing between left and right, which increases user convenience.

[0054] FIG. 6 shows the earphone 1 according to this embodiment being worn in a user's ear. The earphone 1 is worn with the rear surface of the acoustic duct 3 abutting against the tragus 11 (tragus). That is, the earphone 1 is worn in the user's ear by inserting the acoustic duct 3 into the ear canal 12, with the rear surface of the acoustic duct 3 abutting against the tragus 11. As a result, the acoustic duct 3 is pressed by the tragus 11, and 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, because the ear ring 4 is composed of two rings 4A and 4B connected together, it easily elastically deforms and is pressed against the inner wall 13 of the concha.

[0055] Next, in the X-Y coordinate plane, with the left-right direction (front-back direction) of Figure 6 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: The point where the rear surface of the acoustic duct 3 contacts the tragus 11 of the ear is designated a, the point where the earring 4 contacts the inner wall 13 of the concha is designated b, and the point where the earphone body 2 contacts the cheek is designated c.

[0056] 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, hitting point b on the inner wall 13 of the concha, and the ear ring 4 is compressed between the acoustic duct 3 and the inner wall 13. This causes the ear ring 4 to elastically deform and bend in an arc as shown in FIG. 6 , and at point b, it receives a reaction force (resistance) R1 from the inner wall 13 of the concha. This reaction force R1 then generates a moment M in the direction of the arrow (clockwise) in the earphone 1, 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.

[0057] 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 sin θ R1x = R1 sin θ R2x = 0 As shown in the above equations, the X-axis component of the reaction force R2 is R2x = 0, so F = R1 holds.

[0058] Furthermore, the Y-axis components Fy, R1y, and R2y of the external force F and the two reaction forces R1 and R2 are respectively expressed by the following equations: Fy = F · cos θ R1y = R1 · cos θ R2y = R2

[0059] Here, when 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 holds: R1y L1 = R2 L2 (1)

[0060] Therefore, the reaction force R2 that the earphone main body 2 (lower case 2B) of the earphone 1 receives from the cheek 14 of the user can be calculated from the above formula (1) as follows: R2 = R1y (L1 / L2) = R1 cos θ (L1 / L2) = F cos θ (L1 / L2) (2)

[0061] Therefore, according to the principle of action and reaction, the user's cheek 14 receives a pressure P at point c from the earphone 1 that is equal in magnitude to but opposite in direction to the reaction force R2 expressed by equation (2).

[0062] 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 the earphone 1 fits securely into the user's ear, improving wearability. Variations in the size and shape of the user's auricle and ear canal 12 are absorbed by the elastic deformation of the earring 4, so the earphone 1 can be worn securely by any user and will not easily come off or fall out of the ear, even when the user moves vigorously.

[0063] As explained above, when wearing the earphone 1 of this embodiment, the earring 4 elastically deforms due to the force F received when the side of the acoustic duct 3 abuts against the tragus 11 of the ear, and presses against the inner wall 13 of the concha, more specifically, the inner wall of the concha. Then, a moment M generated by a reaction force R1 received by the earring 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 fits securely in the user's ear when worn, with the tip of the earring 4 pressing against the inner wall of the concha and the end of the earphone body 2 pressing against the cheek.

[0064] As such, unlike conventional earplug-type earphones that are worn by inserting earpieces or the like attached to acoustic ducts into the ear, the earphone 1 of this embodiment does not press against the inner wall of the ear canal with the acoustic duct 3. For this reason, the acoustic duct 3 can be made of a hard material and can be thinner than the ear canal. This allows the user to enjoy a comfortable fit without feeling any pressure.

[0065] When the earphones 1 of this embodiment are bone conduction earphones, when the earphones 1 are fitted and worn on the left and right auricles 10 of a user, the electrical signals of the sound (speaker sound) emitted from the speakers 5 are converted into mechanical vibrations by a transducer (not shown) built into the earphone body 2. The mechanical vibrations are conducted to the bones near the user's ears via the acoustic duct 3, vibrating the bones. The bone vibrations are then transmitted to the cochlea, where the vibrations of the lymphatic fluid in the cochlea are converted into electrical signals and transmitted to the auditory nerve, which the brain recognizes as sound. Therefore, even hearing-impaired individuals with abnormalities in the eardrum or ossicles can reliably hear sounds through bone conduction as long as their cochlea and auditory nerves are normal. The earphones 1 of this embodiment can achieve high volume and sound quality because the vibrations from the speakers 5 are transmitted directly to the user's bones via the acoustic duct 3 inserted into the ear canal 12. That is, in this embodiment, the acoustic duct 3 is inserted into the external auditory canal 12 of the user's ear, and the acoustic duct 3 is made of a highly rigid hard resin (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, thereby achieving a high sense of volume and sound quality.

[0066] When 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, connecting the speaker 5 to the ear canal of the ear. Speaker sound is introduced into the ear canal of the user's ear through this communication passage and 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 ambient noise, and preventing touch noise and the user's own voice from echoing.

[0067] As a result, with the earphone 1 according to this embodiment, when a user wears the earphone, the acoustic duct is inserted into the ear canal through the external auditory canal of the user's ear. The side of the acoustic duct abuts against the tragus of the ear, which presses against the acoustic duct. The force exerted by the acoustic duct causes the earring to elastically deform and abut against the inner wall of the concha, more specifically, the inner wall of the concha, pressing against the inner wall. The earring 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 abut against the user's cheek, pressing against the cheek and receiving a reaction force from the cheek. Therefore, according to the principle of action and reaction, the earphone according to this embodiment presses against the inner wall of the concha and the cheek with a pressure force equal in magnitude to the two reaction forces but in opposite directions. As a result, even earphones that employ 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 wearing comfort.

[0068] 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).

[0069] As described above, the earphone 1 of this embodiment is fitted by swinging like a seesaw, so even if the earphone body is large or heavy, it can be fitted securely without feeling any pressure on the ear. Therefore, it is possible to increase the diameter of the speaker diaphragm to improve sound quality, or to increase the size of the battery and circuit board to add various functions.

[0070] Furthermore, with the earphone 1 of this embodiment, one side of the acoustic duct only needs to abut 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, thereby reducing the feeling of pressure on the ear.

[0071] 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 perceived volume and sound quality.

[0072] (Modification) Next, a modification of the above-described embodiment will be described with reference to Figs. 7 to 9. Fig. 7 is a diagram showing a substrate incorporated into an earphone according to a modification of the present invention. Fig. 8 is a cross-sectional view of an acoustic duct of an earphone according to a modification of the present invention. Fig. 9 is a cross-sectional view of an earphone according to a modification of the present invention. Note that in the following description of this modification, only the configuration that differs from the above-described embodiment will be described, and a description of the common parts will be omitted.

[0073] This modification differs from the above-described embodiment in that the acoustic duct 3 includes at least one sensor for detecting the user's biological information. In other words, the earphones of this modification also function as a device for measuring the user's biological information. In this specification, "biological information" refers to information related to the state of a living organism, specifically, information related to the living organism's health and physical activity. Biological information detected by the present invention includes, but is not limited to, 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.

[0074] In this modification, the acoustic duct 3 has the 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 is equipped with a pulse sensor (HR sensor) 8 and a temperature sensor 9. In this modification, as shown in FIGS. 7 to 9 , the acoustic duct 3 incorporates a substrate 10 on which the pulse sensor 8 and the temperature sensor 9 are mounted. The pulse sensor 8 and the temperature sensor 9 are attached so as to be exposed on the surface of the acoustic duct 3 that abuts the tragus, and when worn, they come into contact with the skin behind the tragus inside the ear canal. The substrate 10 is not particularly limited, but can be a deformable substrate, such as a flexible printed circuit (FPC).

[0075] The pulse sensor 8 is a reflective pulse wave sensor that detects pulse rate, blood oxygen saturation (SpO2), etc. by irradiating light of a predetermined wavelength onto the skin inside the ear canal and measuring the reflected light.

[0076] The temperature sensor 9 is a sensor that includes a thermal contact type temperature detection element such as a thermistor, and detects the temperature of the skin, that is, body temperature, by contacting the skin in the ear canal.

[0077] In the present invention, the sensor provided in the acoustic duct is not particularly limited as long as it is a sensor capable of acquiring the user's biometric information, 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.

[0078] 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 to acquire biological information through the skin, but may also be a sensor that acquires 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.

[0079] The earphone of the present invention may also be equipped with an acceleration sensor to acquire biometric information such as the tilt (posture) of the user's head and the state of movement.

[0080] Although the earphone 1 of this modified example is equipped with two sensors, a pulse sensor 8 and a temperature sensor 9, the earphone of the present invention is not limited to this and may be equipped with only one sensor or three or more sensors. Furthermore, the earphone of the present invention may measure one or multiple pieces of biological information.

[0081] 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, the biometric information can be acquired stably without being affected by sunlight or other factors.

[0082] The main body 2 of the earphone 1 of this modified example may house a board connected to the board 10 incorporated in the acoustic duct 3, or the board may be formed integrally with the board 10. The electronic components mounted on the board inside the main body 2 include an A / D converter that converts analog signals detected by the pulse sensor 8 and the body temperature sensor 9 into digital signals, storage means that temporarily store the converted digital signals, and communication means that transmits measured data to an external terminal or the like.

[0083] The earphone 1 according to this modification fits securely in the user's ear without causing any pressure on the user, thereby achieving the effect of accurately measuring the user's biometric information.

[0084] The earphones of the present invention may be configured such that, for example, the earphone worn on one ear further functions as a biological information measuring device, as in the above-described modified example, and the earphone worn on the other ear only functions as an earphone. This allows the user to wear an earphone with the functions of a biological information measuring device and an earphone with only earphone functions on the left and right ears, respectively, and enjoy music or the like with both ears while measuring biological information with one ear.

[0085] 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, allowing you to enjoy music or other sounds with both ears while measuring different biological information with each ear.

[0086] Conventionally, wristwatch-type biological information measurement devices worn on the user's wrist have been known as devices for measuring biological information. However, wristwatch-type biological information measurement devices are prone to noise caused by the user's hand movements during training and daily life. Furthermore, wristwatch-type devices cannot completely block external light, which reduces the accuracy of the optical sensor.

[0087] In contrast, the earphone of the present invention is worn by swinging the entire earphone like a seesaw around the point where the tragus of the acoustic duct, which serves as the measurement unit, abuts (point a in Figure 6). When the earphone of the present invention is worn as described above, the side of the acoustic duct closely contacts the tragus side of the user's ear canal. Because the tragus is highly elastic, the side of the acoustic duct adheres very closely to the skin on the tragus side of the ear canal. Because the tragus is home to many capillaries and has thin skin, the sensor included in the acoustic duct closely contacts this area, enabling accurate measurement of vital signs such as pulse rate.

[0088] Furthermore, because the earphones of the present invention measure biometric information inside the ear canal, they can block external light better than conventional wristwatches, improving accuracy even when using optical sensors. Furthermore, 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, whether during training or daily life.

[0089] Furthermore, in the earphone of the present invention, sensors are provided in a long acoustic duct that is inserted into the ear canal, so multiple sensors can be arranged along the length of the acoustic duct.

[0090] Furthermore, the portion functioning as the biological information measuring device of the present invention can be attached to other types of earphones in addition to the earphones of the present invention. That is, the sensor for detecting the user's biological information of the present invention can be attached to the acoustic duct of any earphone, not just the earphones of the present invention, to make the earphones capable of detecting biological information in the ear canal.

[0091] It should be noted that the present invention is not limited to the application of the above-described embodiments, and various modifications are possible within the scope of the claims and the technical ideas described in the specification and drawings.

[0092] 1: Earphone, 2: Earphone body, 2A: Upper case, 2B: Lower case, 3: Acoustic duct, 3A: Acoustic duct mating convex portion, 3a: Acoustic duct engagement protrusion, 3b: Acoustic duct engagement groove, 4: Ear ring, 4A, 4B: Ring, 4a: Ring mating recess, 4b: Ring engagement groove, 4c: Ring engagement protrusion, 5: Speaker, 6: Multifunction button, 7: Cover, 11: Tragus, 12: Ear canal, 13: Inner wall of concha, 14: Cheek

Claims

1. An earphone comprising: an acoustic duct made of a hard material and inserted into the ear canal; an earphone main body connected to the end of the acoustic duct opposite the insertion direction; and an elastically deformable ear ring attached to the outer surface of the acoustic duct, wherein the length of the acoustic duct on the central axis is 5 mm to 13 mm, the ear ring extends from the outer surface of the acoustic duct at an inclination angle of 60° to 100° relative to the acoustic duct, and the earphone main body extends 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.

2. The earphone according to claim 1, wherein the length of the earphone body along the central axis is 15 mm to 75 mm.

3. The earphone according to claim 1 or 2, wherein, when worn, the earring is elastically deformed by a force received when the side of the acoustic duct comes into contact with the tragus of the ear, pressing against the inner wall of the concha, and a moment generated by a reaction force received by the earring from the inner wall of the concha causes the end of the earphone body to press against the cheek.

4. The earphone according to claim 1 or 2, wherein the ear ring is removably attached to the acoustic duct.

5. The earphone according to claim 1 or 2, wherein the longitudinal length of the ear ring is 12 to 20 mm.

6. The earphone according to claim 1 or 2, wherein the earring is formed by connecting two rings together.

7. The earphone according to claim 1 or 2, wherein the acoustic duct is formed integrally with the earphone body.

8. The earphone according to claim 1 or 2, wherein a speaker is built into the earphone body, and the speaker is disposed directly above the acoustic duct.

9. The earphone according to claim 1 or 2, which is an air conduction earphone.

10. The earphone according to claim 1 or 2, which is a bone conduction earphone.

11. The earphone according to claim 1 or 2, wherein the acoustic duct is provided with at least one sensor for detecting a user's biological information.

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