JP2008278329A - Hearing aid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hearing aid which can be improved in usability. <P>SOLUTION: A rechargeable battery 5 is used as the power source of a hearing aid 1, which has a charging unit 12 for charging the rechargeable battery 5. The hearing aid 1 is stored in a dry case 17 when not used and then a charger 19 provide din the dry case 17 supplies electric power to the charging unit 12 without contacting, so that the charging unit 12 fully charges the rechargeable battery 5. Further, a lithium ion secondary battery which can be charged fast with a current of ≥10C is used as the built-in rechargeable battery 5. Here, "C" is a unit representing a charging/discharging rate, and 1C represents a calculated rate at which constant-current charging from a fully discharged state to a fully charged state is completed within one hour. When a 1/10 hour is needed, the rate is represented as 10C. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a hearing aid used as an auxiliary tool for a hearing impaired person.

  Hearing aids are extremely important for hearing impairment, and the number of elderly people who require hearing aids tends to increase due to the extension of life expectancy due to the development of medical technology.

  By the way, although the thing of various structures, such as what is disclosed by patent document 1, for example, is considered, the hearing aid uses the air zinc battery as a power supply. This was due to the fact that mercury batteries were used before, but production was discontinued due to environmental problems, and the replacement of air zinc batteries with the same voltage has been promoted.

  A zinc-air battery is a battery that uses zinc for the negative electrode and oxygen in the air for the positive electrode. Its energy density is higher than other batteries, so the battery life, that is, the period until battery replacement is relatively long. It is said to be excellent. However, on the other hand, since the air holes are opened by taking in air from the outside, changes in the external environment affect the battery characteristics. For example, depending on external humidity and temperature, battery performance may be reduced and battery life may be shortened.

  In addition, since the zinc-air battery requires an air hole for taking in air, the hearing aid cannot have a sealed structure, and a special waterproof mechanism is required to provide a waterproof function, and an extremely complicated structure is required. The Therefore, it is difficult to enter a place that requires waterproofing with the hearing aid attached, and until now, the hearing aid has to be removed one by one.

  Furthermore, the air zinc battery is a disposable primary battery, although it has a high energy density and a long life. For this reason, it is necessary to periodically replace the battery before the battery performance is lowered and the battery cannot be used. However, it is troublesome to take out and replace a small zinc-air battery from the hearing aid body, and it cannot be said that it is particularly easy for elderly people. In addition, the cost burden for purchasing a battery is not light, and it is one of the problems, and the need to reduce battery replacement is increasing. Conventionally, in order to make the battery last longer, it has been considered to remove the battery when the hearing aid is not used, but this also requires a troublesome work similar to battery replacement.

  On the other hand, hearing aids are stored in a dry case without removing the battery even when not in use, in order to remove moisture such as sweat that is attached to the hearing aid.

However, in this method, when a zinc-air battery is used as the battery, the zinc-air battery has a hole for taking in air from the outside, so that moisture in the battery is removed by long-term storage in a dry case. The battery performance may be significantly reduced and the life may be shortened. Therefore, it is not preferable to put the hearing aid in a dry case without removing the battery.
Japanese Patent Laid-Open No. 9-215098 JP-A-2005-123183

  Therefore, conventionally, a hearing aid using a rechargeable battery as a power source has been considered. Since rechargeable batteries do not require battery replacement, there is no need to perform the troublesome work of handling small batteries when replacing batteries, and there is no cost for purchasing batteries. Furthermore, since there is no problem even if it is dried, it can be stored in a dry case without removing the battery when not in use.

  However, the rechargeable battery has a lower energy density than the primary battery. In particular, the zinc-air battery is a high energy density battery among primary batteries, and the difference from the rechargeable battery is very large. Therefore, a hearing aid employing a rechargeable battery has a short battery life and must be repeatedly charged. However, in the case of a nickel metal hydride battery that has been generally used as a rechargeable battery, charging time of 8 to 12 hours is required. Therefore, if the battery runs out during use, the rechargeable battery is charged. You have to wait for a long time to complete, and you will not be able to use the hearing aid during that time.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a hearing aid that can improve usability.

  According to the first aspect of the present invention, there is provided a hearing aid main body for converting sound from the outside into an electric signal by a microphone, amplifying the converted electric signal and reproducing it from a speaker, and provided in the hearing aid main body. And a rechargeable battery that can be rapidly charged with a current of 10 C or more, which is used as a power source for supplying electric power necessary for the operation.

  The invention according to claim 2 is characterized in that, in the invention according to claim 1, further comprising a drying case, the drying case further includes charging means for charging the rechargeable battery.

  According to a third aspect of the present invention, in the second aspect of the present invention, the charging unit is configured to transmit a radio wave having a predetermined strength, and to receive the radio wave transmitted from the unit and to charge the rechargeable battery. It has the means to generate | occur | produce.

  The invention according to claim 4 is the invention according to claim 3, characterized in that the hearing aid main body has a waterproof function.

  ADVANTAGE OF THE INVENTION According to this invention, the hearing aid which can improve usability can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIGS. 1A and 1B show a schematic configuration of a hearing aid to which the first embodiment of the present invention is applied. In FIG. 1, reference numeral 1 denotes an ear hook type hearing aid. The hearing aid 1 includes a main body 1a and an ear hook 1b as a hearing aid body. The main body 1a is provided with a microphone 2 and a volume 3, and further, a battery storage 4 is provided. The microphone 2 converts sound from the outside into an electric signal. The volume 3 adjusts the volume of the playback sound of the speaker 6 described later. The battery storage unit 4 stores a rechargeable battery 5. The rechargeable battery 5 will be described later.

  In addition, a speaker 6 is built in the ear hook 1b. The speaker 6 reproduces the electric signal converted into an electric signal by the microphone 2 and generates an audio output.

  In this case, the microphone 2, the volume 3, the battery storage unit 4, and the speaker 6 are waterproofed by waterproof means such as packing (not shown), starting between the main body 1 a and the ear hook 1 b. The whole has a waterproof function.

  FIG. 2 shows a circuit configuration of the hearing aid 1. In FIG. 2, the same parts as those in FIG.

  In FIG. 2, the rechargeable battery 5 is used as a power source that supplies power necessary for the operation of the hearing aid 1. As this rechargeable battery 5, a lithium ion secondary battery capable of rapid charging is used in the present embodiment. This lithium ion secondary battery includes a container made of an outer member made of an aluminum can, a nonaqueous electrolyte housed in the container, and lithium cobalt oxide in a positive electrode current collector made of aluminum foil and housed in the container. A positive electrode carrying a positive electrode layer containing as a positive electrode active substance; and a negative electrode carrying a negative electrode layer containing lithium titanium oxide as negative electrode active material particles in a negative electrode current collector made of aluminum foil and housed in the container. Have a structure.

  Here, the lithium ion secondary battery of the embodiment will be described in more detail. Such a lithium ion secondary battery includes a negative electrode containing lithium titanium oxide as an active material. As disclosed in Patent Document 2, lithium titanium oxide as an active material is a material capable of inserting and extracting lithium, and insertion / extraction of lithium ions is performed in the vicinity of 1.4 V to 1.7 V / Li. . For this reason, even if the secondary battery is rapidly charged with a large current, it is possible to ensure safety without causing lithium deposition compared to the case where a carbon material is used as a conventional negative electrode active material. In addition, since expansion and contraction associated with insertion and extraction of lithium can be suppressed, structural destruction of the negative electrode active material can be suppressed even when rapid charging with 20 C current is repeatedly performed. As a result, a long life can be maintained even when charging and discharging are repeated. The battery potential is about 2.4V.

  Specifically, it was confirmed that the lithium ion secondary battery assembled by the following method is a fast charge secondary battery that can be charged to about 80% battery capacity by charging at 20 C for 3 minutes. ing. Here, “C” is a unit representing a charge / discharge rate, and a rate that can be calculated in one hour when a constant current charge from full discharge to full charge (or from full charge to full discharge) is calculated is expressed as 1C. In the case of 1/10 hour, it is expressed as 10C. Therefore, for example, 20C charging requires 20 times as much current as 1C charging.

<Production of negative electrode>
As an active material, lithium titanate (Li ₄ Ti ₅ O ₁₂ ) powder having an average particle diameter of 5 μm and an Li storage potential of 1.55 V (vs. Li / Li ⁺ ), and carbon having an average particle diameter of 0.4 μm as a conductive agent. The powder and polyvinylidene fluoride (PVdF) as a binder were blended in a weight ratio of 90: 7: 3, and these were dispersed in an n-methylpyrrolidone (NMP) solvent to prepare a slurry.

  In addition, the laser diffraction type particle size distribution measuring apparatus (Shimadzu Corporation model number SALD-300) was used for the measurement of the particle diameter of an active material. First, about 0.1 g of a sample was put in a beaker or the like, and then a surfactant and 1 to 2 mL of distilled water were added and stirred sufficiently, and poured into a stirred water tank. The light intensity distribution was measured 64 times at intervals of 2 seconds, the particle size distribution data was analyzed, and the particle size (D50) having a cumulative frequency distribution of 50% was defined as the average particle size.

Next, an aluminum foil (purity: 99.99%) having a thickness of 10 μm was applied to the negative electrode current collector, dried, and then pressed to prepare a negative electrode having an electrode density of 2.4 g / cm ³ .

<Preparation of positive electrode>
Lithium cobalt oxide (LiCoO ₂ ) as an active material, graphite powder as a conductive material, and polyvinylidene fluoride (PVdF) as a binder are blended in a weight ratio of 87: 8: 5. -A slurry was prepared by dispersing in a methylpyrrolidone (NMP) solvent. The slurry was applied to an aluminum foil (purity 99.99%) having a thickness of 15 μm, dried, and pressed to prepare a positive electrode having an electrode density of 3.5 g / cm ³ .

<Assembly of secondary battery>
As a forming material for the container (exterior member), an aluminum-containing laminate film having a thickness of 0.1 mm was prepared. The aluminum layer of this aluminum-containing laminate film had a thickness of about 0.03 mm. Polypropylene was used as the resin for reinforcing the aluminum layer. By laminating this laminate film by thermal fusion, a container (exterior member) was obtained and further contained in a metal aluminum container.

  Next, a positive electrode terminal was electrically connected to the positive electrode, and a negative electrode terminal was electrically connected to the negative electrode. A separator made of a polyethylene porous film having a thickness of 12 μm was coated in close contact with the positive electrode. The positive electrode covered with the separator was overlapped with the negative electrode so as to face each other, and these were wound in a spiral shape to produce an electrode group. Then, the prepared electrode is inserted using the cylindrical aluminum can as a battery container. At this time, the aluminum foil as the positive electrode current collector is electrically connected to the cylindrical aluminum can.

Furthermore, 1.5 mol / L of LiBF ₄ as a lithium salt was dissolved in an organic solvent in which ethylene carbonate (EC) and γ-butyllactone (GBL) were mixed at a volume ratio (EC: GBL) of 1: 2. A liquid non-aqueous electrolyte was prepared. The obtained nonaqueous electrolyte was poured into the container, and the container opening was sealed with a sealing body using laser welding to assemble a cylindrical lithium secondary battery. Such a lithium secondary battery can be used at a full charge voltage of 2.8 V and a discharge end voltage of 1.5 V.

  In this embodiment, the rechargeable battery 5 is a small cylindrical lithium ion secondary battery having a diameter of about 6 to 7 mm and a length of about 20 mm. More than 80% in 5 minutes by 10C charging and 80% in 3 minutes by 20C charging. What can be charged as described above is used.

  The rechargeable battery 5 is connected to a control unit 11 as a control unit. The control unit 11 is connected to the microphone 2, the volume 3, and the speaker 6 described above.

  Further, the control unit 11 has a hearing aid processing unit 111. The hearing aid processing unit 111 performs hearing aid processing such as frequency adjustment and amplification on the electrical signal output from the microphone 2 and outputs the signal from the speaker 6.

  A charging unit 12 is connected to the rechargeable battery 5 as a means for generating charging power of the charging means. The charging unit 12 supplies charging power to the rechargeable battery 5 in a state where the hearing aid 1 is housed in a dry case 17 described later. In this case, the charging unit 12 includes an antenna coil 13, a receiving unit 14, a rectifying / smoothing unit 15, and a storage unit 16. The antenna coil 13 is disposed inside the main body 1a of the hearing aid 1, and receives radio waves (electromagnetic waves) from a transmitter 21 of the charger 19 described later. The receiving unit 14 detects the radio wave received by the antenna coil 13. The rectifying / smoothing unit 15 converts the signal detected by the receiving unit 14 into DC power. The storage unit 16 stores the DC power converted by the reception unit 14 and charges the rechargeable battery 5 using the stored power.

  When such a hearing aid 1 is not used, it is stored in a dry case 17 as shown in FIG. 3 in order to remove moisture such as sweat attached during use. In this case, the drying case 17 has a case body 17a made of a synthetic resin having a bottomed cylindrical shape, and a lid body 17b made of a synthetic resin that closes the opening of the case body 17a with airtightness. The case body 17a stores a desiccant (not shown) such as silica gel. A shelf 18 is provided inside the case body 17a. The shelf 18 is formed with a large number of holes 18a, and the hearing aid 1 is placed on the top. In addition, a charger 19 is provided below the shelf 18 as means for transmitting radio waves (electromagnetic waves) having a predetermined strength of the charging means. The charger 19 generates electric power necessary for charging the rechargeable battery 5 in a non-contact manner by using electromagnetic induction in the charging portion 12 of the hearing aid 1 placed on the shelf portion 18. As shown, the power supply unit 20, the transmission unit 21, and the coil 22 are included. The power supply unit 20 generates power necessary to drive the transmission unit 21 from a 100 V commercial power supply supplied via the power cord 23. The transmitter 21 is driven by the power supply of the power supply unit 20 and transmits a predetermined radio wave via the coil 22. In this case, the transmitter 21 outputs a radio wave having a strength that can obtain power necessary for charging the rechargeable battery 5 by the charging unit 12 of the hearing aid 1.

  Next, the operation of the embodiment configured as described above will be described.

  First, when the hearing aid 1 is used, the ear hook 1b is put on the user's ear and used. In this case, the hearing aid 1 is supplied with power necessary for the entire operation by the rechargeable battery 5.

  In this state, the sound from the outside is converted into an electric signal by the microphone 2 and given to the hearing aid processing means 111 of the control unit 11. The hearing aid processing unit 111 performs hearing aid processing such as frequency adjustment and amplification on the electrical signal output from the microphone 2 and outputs the electrical signal from the speaker 6.

  On the other hand, when not in use, the hearing aid 1 is stored in a dry case 17 in order to remove moisture such as sweat attached during use. In this case, as shown in FIG. 3, the lid 17b of the opening of the case body 17a of the dry case 17 is opened, the hearing aid 1 is placed on the shelf 18, and the lid 17b is closed again. The case body 17a contains a desiccant (not shown) such as silica gel, and moisture attached to the hearing aid 1 is removed in the sealed case body 17a.

  In this state, when 100 V commercial power is supplied to the power supply unit 20 of the charger 19 through the power cord 23, the transmission unit 21 is driven by using the power supply unit 20 as a power source, and the predetermined power is supplied via the coil 22. Radio waves are transmitted. At this time, the radio wave output from the transmitting unit 21 is strong enough to obtain the power necessary for charging the rechargeable battery 5 by the charging unit 12 of the hearing aid 1.

  The charging unit 12 of the hearing aid 1 receives the radio wave output from the transmitting unit 21 of the charger 19 by the antenna coil 13 and detects the radio wave received by the receiving unit 14. Then, the rectifying / smoothing unit 15 converts the signal detected by the receiving unit 14 into DC power, stores the DC power in the storage unit 16, and charges the rechargeable battery 5 to full charge using the stored power. To do.

  Therefore, in this way, the rechargeable battery 5 is used as the power source of the hearing aid 1, and the charging section 12 for charging the rechargeable battery 5 is provided, and the hearing aid 1 is stored in the dry case 17 when not in use. Thus, electric power is supplied to the charging unit 12 from the charger 19 provided in the drying case 17 in a non-contact manner, and the charging unit 12 can charge the rechargeable battery 5 until it is fully charged. Further, as the rechargeable battery 5 to be incorporated, a lithium ion secondary battery that can be rapidly charged with a current of 10 C or more is used.

  As a result, the rechargeable battery 5 can be rapidly charged in a short time of about several minutes, and the rechargeable battery 5 can be repeatedly charged. Therefore, even when the hearing aid 1 is continuously used, Can be recharged quickly, can be used without interrupting the use of the hearing aid 1 for a long time, and the usability can be improved.

  Further, the use of the rechargeable battery 5 as a power source eliminates the troublesome work of replacing the battery. In this case, it is necessary to charge the rechargeable battery 5 instead of replacing the battery. Since the battery capacity is smaller than that of the air zinc battery, the number of times of charging is increased. Since it is only necessary to be unaware of charging such as storing it, a small and troublesome work such as battery replacement is not required at all, and the usability of the hearing aid 1 can be improved in this respect as well.

  Furthermore, by using the rechargeable battery 5 as the power source, eliminating the air hole for taking in air by not using the air zinc battery, and further adopting terminalless charging using electromagnetic induction as the charging method of the hearing aid 1 Since the entire hearing aid 1 can be made waterproof with a liquid-tight structure, the user can enter a water area such as a bath or a pool even with the hearing aid 1 attached, and the user's range of action can be expanded. There is also.

  In addition, this invention is not limited to the said embodiment, In the implementation stage, it can change variously in the range which does not change the summary. For example, in the above-described embodiment, an example in which a non-contact electromagnetic induction method is used for charging the hearing aid 1 has been described, but contact-type charging can also be applied. In this case, since the waterproof function of the hearing aid 1 is impaired, the behavior of entering the water field such as a bath or a pool with the hearing aid 1 on is restricted. In the above-described embodiment, the ear-hook type hearing aid is described. However, the present invention can also be applied to an ear-shaped hearing aid.

  Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, the problem described in the column of the problem to be solved by the invention can be solved, and is described in the column of the effect of the invention. If the above effect is obtained, a configuration from which this configuration requirement is deleted can be extracted as an invention.

The figure which shows schematic structure of the hearing aid of the 1st Embodiment of this invention. The figure which shows the circuit structure of the hearing aid of 1st Embodiment. The figure which shows schematic structure of the drying case used for 1st Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Hearing aid, 1a ... Main part, 1b ... Ear hook 2 ... Microphone, 3 ... Volume 4 ... Battery storage part, 5 ... Rechargeable battery 6 ... Speaker, 11 ... Control part, 111 ... Hearing-aid processing means 12 ... Charging , 13 ... antenna coil 14 ... receiving part, 15 ... rectifying and smoothing part 16 ... accumulating part, 17 ... drying case 17a ... case main body, 17b ... lid body, 18 ... shelf part 18a ... hole part, 19 ... charger 20 ... Power supply part, 21 ... Transmitting part 22 ... Coil, 23 ... Power supply cord

Claims (4)

A hearing aid body that converts external sound into an electric signal by a microphone, amplifies the converted electric signal, and reproduces it from a speaker;
A hearing aid, comprising: a rechargeable battery that is provided in the hearing aid body and that can be rapidly charged with a current of 10 C or more used as a power source for supplying power necessary for the operation of the hearing aid body. The hearing aid according to claim 1, further comprising a drying case, and charging means for charging the rechargeable battery in the drying case. The said charging means has a means to transmit the electromagnetic wave of predetermined intensity | strength, and a means to receive the electromagnetic wave transmitted from this means, and generate | occur | produce the charging power of the said rechargeable battery. hearing aid. The hearing aid main body according to claim 3, wherein the hearing aid body has a waterproof function.

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