JP7502095B2 - Assistive listening devices - Google Patents

Description

The present invention relates to a hearing assistance device that includes a speaker that converts an acoustic signal indicative of ambient sound into sound and outputs it from a sound outlet, and a mounting part that positions the speaker at a predetermined position away from the ear canal with the sound outlet facing the listener's ear canal (the entrance to the ear canal).

As this type of device, the hearing assistance device and near-ear speaker device disclosed in the following Patent Documents 1 and 2 are known. In the hearing assistance device disclosed in Patent Document 1, the speaker is configured to include an enclosure, a speaker unit, a speaker cover, a connecting pin, a sound reflecting material, and a sound absorbing material. In this case, the enclosure is configured to have a circular opening at the front (the front functions as a sound outlet) and a closed rear side. The speaker unit is attached to the front of the enclosure so that the front (sound output surface) side from which sound is output is located at the front side of the enclosure. The speaker cover is formed to cover the opening (sound output port) on the front side of the enclosure and includes a cover portion in which numerous through holes are formed. In addition, as disclosed in the corresponding drawings (Figures 4 and 5 in the same document 1), this cover portion is formed in a flat plate shape and is configured to have small diameter through holes (through holes) that are sufficiently small compared to the diameter of the opening portion of the enclosure formed over almost the entire area. The speaker thus constructed is rotatably connected to a support arm that constitutes the mounting unit via a connecting pin. The mounting unit is also configured to be mountable on the listener's head, and when mounted on the head, the connected speaker can be positioned at a predetermined position away from the ear hole to the side of the head (a predetermined position outside the ear hole) with the speaker facing the listener's ear hole.

The near-ear speaker device disclosed in Patent Document 2 includes a speaker unit (corresponding to the speaker in Patent Document 1) and an ear hook unit (corresponding to the mounting unit in Patent Document 1), and is configured to be mountable on the side of the head (near the ear) of the person to wear it (listener). This near-ear speaker device is also configured such that when mounted on the side of the head (near the ear) of the person to wear it (listener), the ear hook unit can be positioned at a predetermined position away from the ear hole to the side of the head (a predetermined position outside the ear hole) with the connected speaker unit facing the direction of the listener's ear hole.

This speaker section is configured by housing a speaker body (corresponding to the speaker unit in Patent Document 1) in a casing (corresponding to the enclosure in Patent Document 1) attached to one end of the ear hook section. In this speaker section, as in the speaker in Patent Document 1, the opening of the casing is covered by a member corresponding to the cover in Patent Document 1, as disclosed in the corresponding drawing (Figure 1 in Patent Document 2), and this member corresponding to the cover is formed in a flat plate shape and is configured with small-diameter through holes (through holes) that are sufficiently small compared to the diameter of the opening of the casing formed over almost the entire area.

JP 2013-172373 A (pages 7-8, Figures 2-5) Japanese Patent No. 6408243 (page 5, Figure 1)

In the above-mentioned listening assistance device and near-ear speaker device, multiple small-diameter through holes are formed over almost the entire area of the cover portion so that sound from the speaker disposed within the enclosure or casing is output from the opening (sound outlet) of the enclosure or casing to the outside of the enclosure or casing without being impeded by (not affected by) the cover portion attached to this opening. In other words, in this listening assistance device and near-ear speaker device, the cover portion is configured so as not to affect the frequency characteristics related to the sound pressure level of the entire device.

Therefore, in the above-mentioned listening assistance device and near-ear speaker device, the frequency characteristics are tuned by components other than the cover (the speaker unit (speaker body) and the enclosure (casing)) so that a sound that is easy for the listener to hear can be output. In this case, the main purpose of using the listening assistance device and near-ear speaker device is to make it easier for the listener to hear voices among the sounds around the listener (ambient sounds), just like a general hearing aid (a hearing aid in which the sound outlet is inserted into the ear canal). For this reason, in the listening assistance device and near-ear speaker device, the frequency characteristics have been tuned so that the sound pressure level in a specific frequency band, particularly 2 kHz to 4 kHz, in the audio frequency band (for example, a frequency band from 250 Hz to 4 kHz) is higher than the sound pressure level in other frequency bands and is as flat as possible, following the frequency characteristics of a general hearing aid.

As a result, users of these assistive listening devices and near-ear speaker devices have commented that using these devices has significantly improved their ability to hear surrounding sounds, including voices, but there have also been many requests for improvements to be made so that voices can be heard even more clearly.

The present invention was made to meet such demands, and its main objective is to provide a hearing assistance device that enables sounds contained in ambient sounds to be heard more clearly.

In order to achieve the above object, a hearing assistance device according to claim 1 comprises a speaker that converts an acoustic signal indicative of an ambient sound into sound and outputs the sound, and a mounting part that is mounted on the base of a listener's head or auricle and that positions the speaker at a predetermined position away from the listener's ear hole with the sound output port of the speaker facing the listener's ear hole, the speaker having a cylindrical enclosure with a closed rear end and an open front end, and a sound output surface that is located a predetermined distance back from the front end and that is spaced apart from the listener's ear hole by a mounting part that is mounted on the base of a listener's head or auricle and that positions the speaker at a predetermined position away from the listener's ear hole with the sound output port of the speaker facing the listener's ear hole, the speaker having a cylindrical enclosure with a closed rear end and an open front end, the cap has a bottom surface that contacts the front end and a top surface that is formed in a truncated cone shape that protrudes outward from the enclosure, the through hole being formed only on the top surface , and a conductive plate is erected on the periphery of the cap, the tip of which enters the interior of the auricle and contacts the tragus and antitragus of the auricle .

The hearing assistance device of claim 2 is the hearing assistance device of claim 1, in which a plurality of small diameter through holes are formed as the through holes.

The hearing assistance device of claim 3 is the hearing assistance device of claim 1, in which the through hole is a large-diameter through hole that extends over almost the entire top surface, and the cap is provided with a mesh member that covers the large-diameter through hole.

According to the hearing aid device of claim 1, the internal space of the speaker located in front of the sound emission surface of the speaker body is composed of a cylindrical space formed between the sound emission surface and the front end of the enclosure, and a truncated cone-shaped space (space continuous with the cylindrical space) formed by the cap formed in a truncated cone shape, so that the sound pressure level in a specific frequency band of 2 kHz to 4 kHz is not flat overall, but is particularly high at a specific frequency within this specific frequency band, and the specific frequency band as a whole is also high, thereby realizing a frequency characteristic. As a result, with the hearing aid device equipped with this speaker, the sound is more emphasized and the sound contained in the surrounding sound can be heard more clearly compared to a speaker with a frequency characteristic that is flat in the specific frequency band. Furthermore, with this hearing aid device, in addition to the sound emitted from the speaker reaching the eardrum directly, the air-conducted sound generated in the ear canal due to the vibration transmitted to the tragus and the antitragus through the conductive plate reaches the eardrum, so that the listener can hear the surrounding sound including the sound better.

According to the hearing assistance device described in claim 2, since multiple through holes are formed as small diameter through holes, it is possible to prevent foreign matter (such as dust) from entering the speaker from the outside while ensuring a necessary and sufficient amount of sound to be emitted.

According to the hearing assistance device described in claim 3, one large-diameter through hole is formed as the through hole, and a mesh member that covers this large-diameter through hole is arranged in the cap, so that it is possible to prevent foreign matter (such as dust) from entering the speaker from the outside while ensuring a necessary and sufficient amount of sound is emitted.

1 is a perspective view of the external appearance of a hearing assistance device 1. FIG. FIG. 3 is an exploded perspective view of the speaker 2 as viewed from the arrow side in FIG. 2. 2 is a cross-sectional view of the speaker 2 taken along the line W-W in FIG. 5 is a schematic diagram for explaining the cylindrical space SP1 and the truncated cone space SP2 of the speaker 2 in FIG. 4. 4 is a frequency characteristic diagram of the sound pressure level of the speaker 2. FIG. FIG. 2 is an explanatory diagram for explaining a predetermined position of the speaker 2. 11 is a cross-sectional view for explaining another structure of the speaker 2. FIG. 10A and 10B are schematic diagrams for explaining other configurations of the cap 13 of the speaker 2. 10A and 10B are schematic diagrams for explaining other configurations of the cap 13 of the speaker 2. 11 is a cross-sectional view for explaining another structure of the speaker 2. FIG. 2 is a perspective view for explaining the structure of a speaker 2 provided with a conductive plate 41. FIG. FIG. 13 is an explanatory diagram for explaining the speaker 2 of FIG. 12 . 13 is an explanatory diagram for explaining a contact state between a conductive plate 41 and an auricle 54 in the speaker 2 of FIG. 12.

The following describes an embodiment of the hearing assistance device with reference to the attached drawings.

First, the configuration of the hearing assistance device 1 will be explained with reference to the drawings.

Hearing assistance device 1 is an example of a "hearing assistance device" and, as shown in FIG. 1, includes speakers 2, 2 as an example of a "speaker" and a mounting unit 3 as an example of a "mounting unit", and is configured to be mountable on the listener's head by mounting unit 3, as described below.

As shown in Figures 1 to 4, each speaker 2, 2 is identically configured with an enclosure 11, a speaker body (speaker unit) 12, and a cap 13, and converts an acoustic signal output from a sound collection device (not shown) (a device that detects ambient sounds including voice and converts them into an acoustic signal, which is an electrical signal, for output) into sound and outputs it.

The speaker 2, like the speakers and speaker units disclosed in Patent Documents 1 and 2 described in the Background Art, outputs sound toward the ear hole 52 of the listener 51 by the mounting unit 3 mounted on the listener's head, while being held at a predetermined position (outside the ear hole 52) to the side of the ear hole 52 (the entrance to the ear canal 53) of the listener 51 and away from the ear hole 52 and the auricle 54, as shown in FIG. 7. For this reason, the speaker 2 is provided with an enclosure 11 capable of housing a speaker body 12 of a size (diameter) sufficient to output sound to the listener 51 at a necessary and sufficient volume, while being formed in an outer shape that does not disturb the listener 51. In this example, as an example, the speaker 2 is formed in an overall outer shape of a substantially cylindrical body with a diameter L1 of about 18 to 30 mm and a length (thickness) L2 of about 15 to 22 mm, as shown in FIG. 1.

As shown in Figs. 2 and 3, which are exploded perspective views of the speaker 2, and Fig. 4, which is a cross-sectional view of the speaker 2 (cross-sectional view taken along line W-W in Fig. 1), the enclosure 11 is formed as a tube (in this example, a cylinder) having a cylindrical peripheral wall 11a and a disk-shaped bottom wall 11b (both made of synthetic resin material) with a back end (one end of the peripheral wall 11a) closed (specifically, closed by the bottom wall 11b) and a front end (the other end of the peripheral wall 11a) open. Note that the front end of the enclosure 11 refers to the end of the speaker body 12 housed in the enclosure 11 on the side of the diaphragm 12b (which is also the sound-emitting surface) described later, and the back end of the enclosure 11 refers to the end of the speaker body 12 on the side of the magnetic circuit 12c described later. Therefore, the front end of the enclosure 11 refers to the right end in Figures 2 and 4, and refers to the left end in Figure 3. Also, the rear end of the enclosure 11 refers to the left end in Figures 2 and 4, and refers to the right end in Figure 3.

2 and 4, the peripheral wall 11a is formed with a uniform inner diameter (an inner diameter that allows the speaker body 12 to be mounted from the front end) that is approximately equal to the diameter of the speaker body 12 (the outer diameter of the frame 12a described below) in a first region AR1 from the front end to the intermediate portion (the intermediate portion (midway) in the longitudinal direction of the peripheral wall 11a). The peripheral wall 11a is formed with a uniform inner diameter that is smaller than the diameter of the speaker body 12 in a second region AR2 from the intermediate portion to the inner bottom surface of the bottom wall 11b. With this configuration, a step 11c is formed in the above-mentioned intermediate portion (the boundary between areas AR1 and AR2) on the inner surface of the peripheral wall 11a by the portion of the second area AR2 in the peripheral wall 11a, for positioning the speaker body 12 housed in the enclosure 11 in this intermediate portion with the central axis of the speaker body 12 coinciding with the central axis A of the enclosure 11 (which is also the central axis of the peripheral wall 11a).

In this example, the step portion 11c is formed around the entire circumference of the inner circumferential surface of the peripheral wall 11a, but it is not necessary to form the step portion 11c around the entire circumference of the inner circumferential surface of the peripheral wall 11a in order to position the speaker body 12. For example, although not shown, various configurations can be adopted instead of the configuration of this example, such as forming the inner diameter of the peripheral wall 11a to be the same from the front end to the inner bottom surface of the bottom wall 11b, and arranging three or more positioning protrusions at equal intervals along the circumferential direction of the peripheral wall 11a at a position corresponding to the above-mentioned intermediate portion on the inner circumferential surface of the peripheral wall 11a.

In this example, the speaker body 12 is a dynamic speaker unit that includes a cylindrical frame 12a, a diaphragm 12b whose entire outer edge is connected to one end of the frame 12a via an edge (not shown), and a magnetic circuit 12c that drives a voice coil (not shown) disposed on the other end of the frame 12a and connected to the center of the diaphragm 12b. Note that the speaker body 12 is not limited to a dynamic type, and various other types of speaker units such as a capacitor type can be used.

In this embodiment, the cap 13 includes a cylindrical member 13a and a front wall 13b (both made of synthetic resin material) as shown in Figs. 2 to 4. In this case, the cylindrical member 13a has an outer diameter that is approximately equal to the inner diameter of the first area AR1 of the peripheral wall 11a of the enclosure 11 and is formed uniformly so that it can be inserted into the first area AR1 of the peripheral wall 11a of the enclosure 11 with little wobble. The cylindrical member 13a also has a uniform wall thickness, so that the inner diameter is also uniform. The length of the cylindrical member 13a is shorter than the length of the first area AR1 of the peripheral wall 11a that constitutes the enclosure 11 by the width of the frame 12a.

As shown in FIG. 4, the front wall 13b has an outer shape of a truncated cone (a truncated cone with the entire bottom surface open). In addition, the outer diameter of the bottom side of the front wall 13b is formed to be equal to the diameter of the peripheral wall 11a (which is also the diameter L1 of the entire speaker 2) as an example in this example. Therefore, the outer diameter of the bottom side of the front wall 13b is formed to be larger than the cylindrical member 13a inserted into the peripheral wall 11a. In addition, a through hole 13c that functions as a sound outlet (an opening for releasing sound output from the diaphragm 12b of the speaker body 12 to the outside of the speaker 2) is formed in the center of the front wall 13b (a part that has a circular shape in front view corresponding to the upper surface of the truncated cone). In this example, this through hole 13c is formed only in the center as a small-diameter through hole smaller than the diameter of the center of the front wall 13b.

As shown in FIG. 4, the cap 13 is constructed by connecting the outer peripheral edge of the front wall 13b to one end (the right end in the figure) of the cylindrical member 13a configured as described above. The cylindrical member 13a and the front wall 13b thus integrated are in a state in which their respective central axes are aligned.

Next, the assembly of the speaker 2 including the above-mentioned enclosure 11, speaker body 12, and cap 13 will be described. First, as shown in FIG. 4, the speaker body 12 is inserted into the peripheral wall 11a of the enclosure 11 from the magnetic circuit 12c side until the frame 12a abuts against the step portion 11c. As a result, the speaker body 12 is attached to the middle part of the enclosure 11 with its central axis coinciding with the central axis A of the enclosure 11. In other words, the speaker body 12 is housed inside the enclosure 11 with the diaphragm 12b (sound emission surface) located at a position recessed by a predetermined distance L3 (a distance approximately equal to the distance obtained by subtracting the width of the frame 12a from the length of the first region AR1) from the front end of the enclosure 11, and the diaphragm 12b (sound emission surface) facing this front end side.

Next, as shown in FIG. 4, the cylindrical member 13a of the cap 13 is inserted from its other end (the left end in the figure) into the peripheral wall 11a of the enclosure 11 until the outer periphery of the front wall 13b abuts against the front end of the peripheral wall 11a. This attaches the cap 13 to the front end of the enclosure 11 (peripheral wall 11a) and completes the assembly of the speaker 2.

In this assembled state, the front wall 13b of the cap 13 functions as the cap itself, covering the front end of the enclosure 11 (peripheral wall 11a). The other end of the cylindrical member 13a of the cap 13 is in a state where it holds the frame 12a of the speaker body 12 without any rattle between itself and the step portion 11c formed on the inner circumferential surface of the peripheral wall 11a. In addition, since the outer peripheral edge of the front wall 13b is in contact with the front end of the peripheral wall 11a, the entire front wall 13b, including the central portion where the multiple through holes 13c are formed, is in a state where it protrudes outward (outside the enclosure 11) from the front end of the peripheral wall 11a (which is also the front end of the enclosure 11).

In this assembled state, as shown in FIG. 5, which is a schematic representation of FIG. 4, the speaker body 12 is disposed in the middle of the peripheral wall 11a constituting the enclosure 11 (so that the diaphragm 12b (sound emitting surface) of the speaker body 12 is located at a position recessed by a predetermined distance L3 from the front end of the enclosure 11), and the entire front wall 13b of the cap 13, which is disposed in contact with the front end of the enclosure 11, protrudes outward from this front end. As a result, the internal space of the speaker 2 located in front of the diaphragm 12b (sound emitting surface) of the speaker body 12 is composed of a cylindrical space SP1, which is the internal space of the cylindrical member 13a constituting the cap 13, and a truncated cone-shaped space SP2 (a space continuous with the cylindrical space SP1), which is the internal space of the front wall 13b constituting the cap 13.

As shown in FIG. 6, the speaker 2 in this example has frequency characteristics in which the sound pressure level does not rise flatly overall in a specific frequency band between 2 kHz and 4 kHz, but rather rises particularly at specific frequencies within this specific frequency band, while also rising across the entire specific frequency band (in the example in the same figure, as an example, the sound pressure level rises particularly (at a positive peak) at a specific frequency of 3 kHz, while also rising across the entire specific frequency band).

It was confirmed by experiments that such frequency characteristics for sound pressure level could be achieved by forming the cylindrical space SP1 and the truncated cone space SP2 as described above. Furthermore, it was confirmed by experiments that the speaker 2 of this example has such frequency characteristics for sound pressure level, so that the sound is emphasized and can be heard more clearly compared to when the frequency characteristics are such that a specific frequency band is flat.

It was also confirmed through experiments that the specific frequency at which the sound pressure level is particularly high can be tuned by changing the total volume of the cylindrical space SP1 and the truncated cone space SP2, specifically, that the frequency can be shifted to a higher frequency by decreasing the total volume, and that the frequency can be shifted to a lower frequency by increasing the total volume. In addition, experiments were conducted in which multiple types of speakers 2 were prototyped by changing the total volume, but the specific frequency was included in the specific frequency band (2 kHz to 4 kHz), and users were asked to try them out to actually confirm how easy it was to hear. As a result, it was confirmed that the speaker 2 whose specific frequency was included in the frequency band of 2.5 kHz to 3.5 kHz (i.e., the speaker 2 whose specific frequency was a frequency in the vicinity of 3 kHz) was the easiest to hear. Based on the results of these experiments, the speaker 2 in this example has the volumes of the cylindrical space SP1 and the truncated cone space SP2 tuned so that the sound pressure level has the frequency characteristics shown in FIG. 6. The method for changing the total volume may be any of the following: changing only the volume of the cylindrical space SP1, changing only the volume of the truncated conical space SP2, or changing both the volumes of the cylindrical space SP1 and the truncated conical space SP2.

In this embodiment, as shown in FIG. 1, the mounting unit 3 is provided with an elastic arch-shaped band 21 and is configured to be mounted on the listener's head (specifically, from the top to both sides of the head). Specifically, in addition to the band 21, the mounting unit 3 has a pair of pressing parts 22, 22 connected to the respective ends of the band 21 and pressed against the sides of the head by the elastic force of the band 21 when the band 21 is mounted on the head, and support arms 23, 23 connected at one end to the corresponding pressing part 22 and connected to the corresponding speaker 2 at the other end to support the speaker 2 at the above-mentioned predetermined position (a position away from the ear hole 52 and where the sound outlet of the speaker 2 (the multiple through holes 13c formed in the center of the front wall 13b) faces the ear hole 52).

The mounting unit 3 is not limited to the configuration shown in FIG. 1, as long as it can support the speaker 2 in the above-mentioned predetermined position when worn by a listener. For example, it is of course possible to adopt the configuration disclosed in Patent Document 1 described in the background art (a configuration in which the mounting unit is mounted on the back of the listener's head from the back of the head to both sides of the head, and supports two speakers 2 in predetermined positions relative to the left and right ear holes) or the configuration disclosed in Patent Document 2 (a configuration in which the mounting unit is hung on the base of the listener's auricle, and supports one speaker 2 in a predetermined position relative to the ear hole located in the center of the auricle).

In this manner, in this listening assistance device 1, the speaker 2 is housed inside the enclosure 11 with the diaphragm 12b (sound emission surface) located a predetermined distance L3 from the front end of the enclosure 11 and facing the front end, the cap 13 is formed in a truncated cone shape (one end of the cylindrical member 13a is connected to the outer periphery of the truncated cone-shaped front wall 13b), the cylindrical member 13a is inserted into the enclosure 11, the outer periphery of the front wall 13b (the outer periphery of the open bottom surface) comes into contact with the front end of the enclosure 11, the upper surface located in the center (the upper surface of the truncated cone) protrudes outward from the enclosure 11, and a through hole 13c that functions as a sound emission port is formed only in this upper surface.

Therefore, according to the speaker 2, the internal space of the speaker 2 located in front of the diaphragm 12b (sound emitting surface) of the speaker body 12 is composed of a cylindrical space formed between the diaphragm 12b and the front end of the enclosure 11 (in this example, the cylindrical space SP1 which is the internal space of the cylindrical member 13a constituting the cap 13) and a truncated conical space formed by the cap 13 which is formed in a truncated cone shape (in this example, the truncated conical space SP2 which is the internal space of the truncated conical front wall 13b constituting the cap 13; a space continuous with the cylindrical space SP1). Therefore, in a specific frequency band of 2 kHz to 4 kHz, the sound pressure level does not rise flatly overall, but rather it is possible to realize a frequency characteristic (the frequency characteristic shown in FIG. 6 as an example) in which the sound pressure level rises particularly at a specific frequency within this specific frequency band and rises as a whole in the specific frequency band. As a result, with the hearing assistance device 1 equipped with this speaker 2, the sound is emphasized more and the sounds contained in the surrounding sounds can be heard more clearly compared to a speaker with a frequency characteristic that is flat in a specific frequency band.

In addition, with the hearing assistance device 1 equipped with this speaker 2, multiple small-diameter through-holes 13c are formed only in the center (top surface of the truncated cone) of the front wall 13b that constitutes the cap 13, so that a necessary and sufficient amount of sound can be emitted while preventing foreign matter (such as dust) from entering the speaker 2 from the outside.

The through hole 13c formed only in the center (top surface of the truncated cone) of the front wall 13b constituting the cap 13 is not limited to the above-mentioned configuration (a configuration in which multiple small-diameter through holes are formed). For example, as shown in FIG. 8, a single through hole 13c may be formed in the center (top surface of the truncated cone) of the front wall 13b as a large-diameter through hole that extends over almost the entire center (top surface), and this through hole 13c may be covered with a mesh member 31 (which may be made of metal, resin, or cloth). Even with this configuration, it is possible to prevent foreign matter (such as dust) from entering the speaker 2 from the outside while ensuring a necessary and sufficient amount of sound to be emitted. Note that the components of the speaker 2 shown in the figure that are the same as those of the speaker 2 shown in FIG. 4 above will be assigned the same reference numerals and redundant explanations will be omitted.

In addition, as shown in FIG. 5, the front wall 13b constituting the cap 13 has a configuration in which the contour line OL from the outer periphery (bottom surface of the truncated cone) to the center (top surface of the truncated cone) is a straight line when viewed from the side (i.e., the front wall 13b is an exact truncated cone). However, the "frustum shape" in this application is not limited to this exact truncated cone shape, and includes, for example, the front wall 13b shown in FIG. 9 and the front wall 13b shown in FIG. 10, in which the contour line OL from the outer periphery (bottom surface of the truncated cone) to the center (top surface of the truncated cone) is a curved line when viewed from the side (i.e., the front wall 13b is an exact truncated cone). Note that the components of the speaker 2 shown in FIG. 9 and 10 that are the same as those of the speaker 2 shown in FIG. 5 above are given the same reference numerals and redundant explanations are omitted.

In addition, in the above-mentioned configuration of the speaker 2, as shown in Fig. 4, the length of the cylindrical member 13a is set to a predetermined distance L3 in order to sandwich the frame 12a of the speaker body 12 between the other end (left end) of the cylindrical member 13a and the step portion 11c, so that the cylindrical space SP1 is configured as the internal space of the cylindrical member 13a that constitutes the cap 13, but is not limited to this configuration. For example, as in the speaker 2 configured as shown in Fig. 11, in a configuration in which the diaphragm 12b (sound emitting surface) is located at a position recessed by a predetermined distance L3 from the front end of the enclosure 11, the speaker body 12 is fixed to the inside of the enclosure 11 with an adhesive (not shown) or the like, so that there is no need to sandwich the frame 12a of the speaker body 12 between the other end (left end) of the cylindrical member 13a and the step portion 11c, so the length of the cylindrical member 13a can be made shorter than the predetermined distance L3. In a speaker 2 of this configuration, the main function of the cylindrical member 13a that constitutes the cap 13 is to position the front wall 13b that constitutes the cap 13 on the peripheral wall 11a of the enclosure 11, and the cylindrical space SP1 is mainly composed of the internal space of the peripheral wall 11a of the enclosure 11. Even in a speaker 2 of this configuration, because it has a configuration with a cylindrical space SP1 and a truncated cone space SP2, it is possible to realize the frequency characteristics shown in FIG. 6.

In addition, in the above-mentioned hearing assistance device 1, the speaker 2 is supported by the support arm 23 so that the speaker 2 is in a predetermined position away from the ear hole 52 and away from the auricle 54 (in other words, floating from the auricle 54) with the pressing part 22 pressed against the temporal part of the head as a fulcrum. Therefore, in the above-mentioned hearing assistance device 1, the sound emitted from the speaker 2 passes through the ear hole 52 and the ear canal 53 and reaches the eardrum (not shown) directly, so that the listener 51 can hear the surrounding sounds including voice, but the hearing assistance device 1 is not limited to this configuration. The speaker 2 is configured to emit sound to the outside by vibrating the diaphragm 12b of the speaker body 12, so the enclosure 11 of the speaker 2 that houses the diaphragm 12 also vibrates at the frequency of the sound emitted to the outside. Therefore, a configuration can be adopted that utilizes this vibration of the enclosure 11 to enable the listener 51 to better hear the surrounding sounds including voice. Below, the hearing assistance device 1 that employs this configuration will be described with reference to Figures 12 to 14. Note that this hearing assistance device 1 differs from the hearing assistance device 1 described above in that it is equipped with a conductive plate 41 (described below) that transmits vibrations from the enclosure 11 to the auricle 54 of the listener 51, but the rest of the configuration is almost the same. Therefore, the same components are given the same reference numerals and duplicated descriptions will be omitted.

As shown in Figs. 12 and 13, a conductive plate 41 is erected on the periphery of the cap 13 (the outer periphery of the front wall 13b of the cap 13) constituting the speaker 2. In this example, the conductive plate 41 is formed of a synthetic resin material such as elastically deformable silicone rubber on a flat plate (i.e., a flat plate curved along the periphery of the cap 13) that has an arc shape when viewed in plan from the cap 13 side and has a substantially uniform standing height H (see Fig. 13) from the cap 13 and a substantially uniform thickness. The conductive plate 41 has a tip that enters the inside of the auricle 54 (more specifically, the inside of the concha cavity 57 in the auricle 54) as described later. For this reason, the two corners at the tip of the conductive plate 41 are rounded as shown in Figs. 12 and 13 as an example in this example, to facilitate easy entry and improve the fit. The rounding of the corners is optional, and a configuration that does not round them can also be adopted. In addition, the tip of the conductive plate 41 that has entered the inside of the auricle 54 (inside the cavity of the concha 57 in the auricle 54) contacts the tragus 55 and the antitragus 56 located at the entrance of the cavity of the concha 57 at the same time (see FIG. 14), as described below. For this reason, the length L4 (see FIG. 12) of the conductive plate 41 is formed to be longer than the length between the tragus 55 and the antitragus 56.

As a configuration for erecting the conductive plate 41 on the peripheral portion of the cap 13 as described above, although not shown in the figure, a configuration in which the base of the conductive plate 41 is directly fixed to the peripheral portion of the cap 13 or a configuration in which the base of the conductive plate 41 is directly fixed to the front end of the peripheral wall 11a constituting the enclosure 11 can be adopted. However, as an example, in this example, as shown in FIG. 12, a configuration in which the base of the conductive plate 41 is integrally attached to a band member 42 made of a cylindrical elastic body having a diameter slightly smaller than the outer diameter of the peripheral portion of the cap 13 and the front end of the peripheral wall 11a is adopted. In this example, specifically, the conductive plate 41 and the band member 42 are integrally molded using silicone rubber. With this configuration, in this example, the band member 42 is elastically deformed and fitted onto the peripheral portion of the cap 13 and the front end of the peripheral wall 11a, so that the conductive plate 41 is attached in an upright state to the peripheral portion of the cap 13 by the elastic force of the band member 42 (standing on the peripheral portion of the cap 13). Although not shown, a groove into which the band member 42 fits can be provided on the peripheral edge of the cap 13 or on the outer peripheral surface of the front end of the peripheral wall 11a, and the band member 42 can be fitted into this groove.

As described above, in the hearing assistance device 1 in which the conductive plate 41 is erected on the periphery of the cap 13 that constitutes the speaker 2, when the device is worn on the listener's head, as shown in Figs. 13 and 14, the conductive plate 41 provided on the speaker 2 held in a predetermined position to the side of the ear hole 52 of the listener 51 and away from the ear hole 52 and the auricle 54 advances in the direction shown by the white arrow in the figures, with its tip entering the inside of the auricle 54 (more specifically, the inside of the concha cavity 57 shown in Fig. 14), and this tip simultaneously comes into contact with the tragus 55 and the antitragus 56 as shown in Fig. 14.

As a result, in the hearing assistance device 1 equipped with this conductive plate 41, the diaphragm 12b vibrates, causing the sound emitted from the speaker 2 to pass through the ear hole 52 and the ear canal 53 and reach the eardrum (not shown) directly, and the vibration of the diaphragm 12b is transmitted to the tragus 55 and antitragus 56 of the listener 51 (i.e., to the cartilage around the entrance of the ear canal 53) through the enclosure 11 (or the enclosure 11 and the cap 13) and the conductive plate 41. In this case, the vibration transmitted to the tragus 55 and antitragus 56 causes the inner wall of the ear canal 53 to vibrate, generating air-conducted sound from this inner wall into the ear canal 53, which then reaches the eardrum.

Therefore, with the hearing assistance device 1 equipped with this conductive plate 41, in addition to the sound emitted from the speaker 2 reaching the eardrum directly, the above-mentioned air-conducted sound generated in the external auditory canal 53 due to vibrations transmitted through the conductive plate 41 to the tragus 55 and antitragus 56 also reaches the eardrum, allowing the listener 51 to hear surrounding sounds, including voices, better (clearer).

REFERENCE SIGNS LIST 1 hearing assistance device 2 speaker 3 mounting part 11 enclosure 12 speaker body 13 cap 13c through hole (sound outlet)
41 Conductive plate

Claims (3)

A hearing assistance device comprising: a speaker that converts an acoustic signal representing an ambient sound into sound and outputs the sound; and a mounting part that is mounted on the base of a listener's head or auricle and that positions the speaker at a predetermined position away from the listener's ear hole with a sound outlet of the speaker facing the listener's ear hole,
The speaker includes:
a cylindrical enclosure having a closed rear end and an open front end;
a speaker body accommodated in the enclosure with a sound emitting surface located at a position recessed a predetermined distance from the front end and facing the front end;
a cap having a through hole functioning as the sound outlet and attached to the front end of the enclosure,
the cap has a bottom surface in contact with the front end portion, an upper surface formed in a truncated cone shape protruding outward from the enclosure, and the through hole is formed only in the upper surface ;
A conductive plate is provided on the periphery of the cap, and a tip of the conductive plate enters the inside of the auricle and contacts the tragus and antitragus of the auricle . The hearing aid device of claim 1, in which multiple small diameter through holes are formed as the through holes. The through hole is a large-diameter through hole that extends over substantially the entire upper surface,
2. The hearing aid according to claim 1, wherein the cap is provided with a mesh member that covers the large diameter through hole.

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