JP5359511B2 - Artificial larynx - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an artificial larynx capable of obtaining the voice of a desired pitch in a simple structure. <P>SOLUTION: The artificial larynx includes: a cylindrical body 2 to be a body provided with an insertion hole 4 for introducing exhaled air; a piston 3 movably inserted to the insertion hole 4 and moved to one side by an expiratory pressure; an outflow hole 8 for communicating the insertion hole 4 and the outside on the other side of the piston 3; and an elastic vibrator film 11 vibrated by the exhaled air flowing out from the outflow hole 8 and changed in tension by the movement to one side of the piston 3. When the exhaled air is introduced to the insertion hole 4, the piston 3 is pressed to one side by the pressure, the elastic vibrator film 11 is stretched, and the exhaled air passes through the outflow hole 8 and vibrates the elastic vibrator film 11. In such a manner, the piston 3 receives the expiratory pressure, pressed to one side and stopped at a position balanced with the tension of the elastic vibrator film 11, and since the vibration of the elastic vibrator film 11 is changed by the tension and length, especially the tension, a vibration frequency can be changed by the expiratory pressure. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an artificial larynx.

  Conventionally, as a substitute voice acquisition method of this type, there are an esophageal utterance method, a method using an artificial throat, a method using an electric artificial larynx, a TE shunt utterance method, and the like.

  Furthermore, in addition to the above method, attempts have been made in recent years to provide an appropriate sound source driven by exhalation inside the shunt valve, and the shunt valve is provided between the pharynx and the trachea and provided in the airway communicating with the pharynx. As shown in FIG. 12, a shunt valve 101 that allows exhalation to flow only in one direction is provided on the tracheoesophageal wall, and the permanent tracheal hole 102 is closed to guide exhalation to the esophagus 103, and a vocal body is placed in the shunt valve. By providing (for example, Patent Document 1 and Patent Document 2), substitute voice is obtained.

JP 63-116200 A JP-A-1-217400

  The above substitute sound has many problems to be solved such as sound duration, suppression, fundamental frequency, appearance, and convenience, and the demand for a new implantable substitute sound source is very large.

  The sound source with a built-in TE shunt valve must be extremely small, and it is not easy to obtain frequency characteristics similar to those of a healthy person. Moreover, since it is calculated | required to operate | move stably even when saliva, a bodily fluid, and the inflow of food and drinks, structure must be simple.

  Therefore, the present invention provides an artificial larynx that can be easily controlled by changing the expiratory pressure with a simple structure.

(1) In order to achieve the above object, the artificial larynx of the present invention is an artificial larynx through which exhalation passes, a main body having an insertion hole for introducing exhalation, a movably inserted into the insertion hole, and one unit by exhalation pressure. A piston that moves to the side, an outflow hole that communicates the insertion hole and the outside, and an elastic vibrating membrane that vibrates due to exhaled air that has flowed out of the outflow hole and that changes in tension due to movement to one side of the piston, It is characterized by providing.

  When exhalation is introduced into the insertion hole, the piston is pushed to one side by the pressure, the elastic vibrating membrane is extended, and the exhalation passes through the outflow hole and vibrates the elastic vibrating membrane. In this way, the piston receives the expiratory pressure, is pushed to one side, stops at a position that balances with the tension of the elastic vibrating membrane, and the vibration of the elastic vibrating membrane changes depending on the tension and length, especially the tension. The frequency can be changed by the atmospheric pressure. Therefore, the inflection control can be easily performed by changing the expiratory pressure.

  (2) In the above artificial larynx, the elastic vibrating membrane is provided so as to cover the outflow hole.

  As a result, when the exhaled air flows out through the outflow hole and creates a gap between the elastic vibrating membrane and the main body, the elastic vibrating membrane can be vibrated.

  (3) In the artificial larynx, an opening portion communicating with the outside is provided on one side of the insertion hole, and the elastic vibrating membrane is provided in the opening portion.

  The piston moves to one side from the aperture by the expiratory pressure, and tension can be applied to the elastic vibrating membrane provided in the aperture.

  (4) In the artificial larynx, the elastic vibratory membrane is mixed with powder having a specific gravity larger than that of the elastic vibratory membrane.

  Although it is difficult to lengthen the elastic vibrating membrane from the usage conditions, the natural frequency can be lowered by increasing the linear density of the elastic vibrating membrane by mixing metal powder.

  (5) In the above artificial larynx, the powder is a tungsten powder.

  Tungsten is suitable for use because it has a large specific gravity and is chemically stable.

  According to the artificial larynx of the present invention, it is possible to obtain a sound having a desired height with a simple structure.

It is a partially cutaway perspective view of the artificial larynx showing Example 1 of the present invention. It is sectional drawing same as the above. It is a side view same as the above. It is a cross-sectional explanatory drawing of an experimental apparatus same as the above. It is a graph which shows the relationship between a frequency and a sound pressure level same as the above. It is a graph figure which shows an experimental result same as the above. It is sectional drawing of the artificial larynx which shows Example 2 of this invention. FIG. 8 is a cross-sectional view taken along line AA in FIG. It is a side view same as the above. It is a graph which shows the relationship between a driving pressure and a frequency in the case where a piston is movable and fixed same as the above. It is a graph which shows the relationship between the drive pressure at the time of changing the amount of metal powder mixing same as the above. It is a median cross-sectional view of a human head and neck showing a conventional example.

  Preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments described below do not limit the contents of the present invention described in the claims. In addition, all of the configurations described below are not necessarily essential requirements of the present invention. In each embodiment, an unprecedented artificial larynx is obtained by adopting a new artificial larynx different from the conventional one, and the artificial larynx will be described.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 6 show Embodiment 1 of the present invention. As shown in FIG. 1, an artificial larynx 1 is inserted into a cylindrical body 2 that is a substantially cylindrical body and slidably inserted into the cylindrical body 2. A piston 3. An insertion hole 4 for inserting the piston 3 is provided on one side in the length direction in the cylindrical body 2, and an opening 4 </ b> K is provided on one side of the insertion hole 4. On the other side in the direction, an exhalation introduction hole 5 communicating with the insertion hole 4 is provided. The cylindrical body 2 has a size of, for example, an outer diameter of 10 mm and a length of about 20 mm. The artificial larynx 1 is provided in an airway that is interposed between the pharynx and the trachea and communicates with the pharynx. It can be provided in the outer case of the shunt valve provided in the airway.

  The exhalation introduction hole 5 has a circular shape, the exhalation introduction hole 5 is smaller than the insertion hole 4, and a step portion 7 is formed between the exhalation introduction hole 5 and the insertion hole 4. Further, flat surfaces 6 and 6 are formed on both sides of the cylindrical body 2 in the radial direction.

  The piston 3 is connected to the piston main body 3A that is slidably fitted in the insertion hole 4, the contact portion 3B that contacts the stepped portion 7, and the piston main body 3A and the contact portion 3B. The piston main body 3A has a substantially cross-shaped cross section and a gap is provided between the piston main body 3A and the insertion hole 4. The exhaled air introduced from the exhalation introducing hole 5 is the piston main body 3A. It is configured to press. In addition, an outflow hole 8 that penetrates the inside and outside of the cylindrical body 2 is provided at approximately the center in the length direction of the insertion hole 4, and the outflow hole 8 opens in one of the flat portions 6. As shown in FIG. 2, the position where the contact portion 3 </ b> B contacts the stepped portion 7 is the initial position of the piston 3.

  The artificial larynx 1 includes a belt-like elastic vibrating membrane 11 that covers the outflow hole 8 and one side surface 3M of the piston main body 3A. The elastic vibrating membrane 11 has a substantially constant thickness and a substantially constant thickness. Make. The elastic vibrating membrane 11 has one end 11 </ b> A fixed to the other side from the position of the outflow hole 8 of the flat portion 6 on one side of the cylinder 2 by bonding or the like, and the other end 11 </ b> B is fixed to the flat portion 6 on the other side of the piston 3. The one end 11A and the other end 11B are not fixed. When the elastic body film 11 and the outflow hole 8 are arranged in the flat portions 6 and 6 as described above, when the cylindrical body 2 is stored in the cylindrical outer case, the space between the outer case and the cylindrical body 2 is reduced. The elastic vibrating membrane 11 and the outflow hole 8 can be disposed in the space, and a sound generation space can be formed.

  Therefore, when exhalation is introduced from the exhalation introduction hole 5, the piston body 3 </ b> A is pushed to one side by the pressure, the elastic vibrating membrane 11 extends, the exhalation passes through the outflow hole 8, and the elastic vibrating membrane 11 and the cylindrical body 2. The elastic vibrating membrane 11 is vibrated when a gap is formed between the elastic vibrating membrane 11 and the fluid.

  In this way, the piston 3 receives the expiratory pressure, is pushed to one side, and stops at a position that balances the tension of the elastic vibrating membrane 11. It is considered that the vibration of the elastic vibration film 11 can be approximated to the self-excited vibration of the string, and its natural frequency fn is expressed by the following formula 1.

  In Equation 1, T is tension, L is length, and ρ is linear density.

  Since the tension T changes according to the expiratory pressure, the artificial larynx 1 can be easily controlled by changing the expiratory pressure. The elastic vibrating membrane 11 is required to be flexible and have high strength and an appropriate elastic modulus. As a result of trying several materials, silicone rubber (X-32-242, manufactured by Shin-Etsu Chemical Co., Ltd., hardness after curing 12 (durometer A), tensile strength 15 kPa) was adopted. The liquid raw material was molded to a thickness of 0.5 mm using a self-made mold, and then cut into a width of 5 mm and a length of 12 mm to form the elastic vibration member film 11. When the elastic vibrating membrane 11 was used alone, the frequency was very high, which was inappropriate as compared with a general voice frequency of about 130 Hz for men and about 200 Hz for women. This is because the length L and the linear density ρ are small, but it is difficult to increase the length L due to use conditions. Therefore, in order to effectively increase the gland density ρ while maintaining the mechanical properties, tungsten powder having a particle size of 2 μm was mixed into the silicone rubber. The mixing amount was 7% by weight based on the result of the preliminary test. Since the vibration frequency is also affected by the initial tension of the elastic vibration member film 11, care was taken not to apply tension as much as possible when bonding the elastic vibration member film 11 to the cylindrical body 2.

  As shown in FIG. 4, in the experiment, the artificial larynx 1 is held on the upper part of the sealed air chamber 51, and the drive air corresponding to exhalation is sent to the decompressor 53 and adjusted by the compressor 52, and then the drive air A method of guiding the gas from the exhalation introduction hole 5 to the artificial larynx 1 through the flow meter 54 and the air chamber 51 was adopted. In order to prevent resonance with the artificial larynx 1, a sound absorbing material 55 was affixed to the inner wall of the air chamber 51, and the internal pressure was regarded as the driving pressure of the artificial larynx 1 and measured by the air pressure sensor 56. A sound level meter 57 and a microphone 58 were installed at positions 300 mm away from the artificial larynx 1 in order to measure and record the sound pressure level of the artificial larynx 1. The voltage outputs obtained from the air pressure sensor 56, the sound level meter 57, and the microphone 58 were recorded in the computer 61 by the A / D converter 59 at a sampling frequency of 20 kHz. After the experiment, the frequency analysis of the speech waveform was performed by FFT analysis with a Hamming window. In the figure, 60 is an amplifier for amplifying the data of the microphone 58, and 61 is a personal computer.

FIG. 5 shows, as an example, a voice waveform and an FFT analysis result when the driving pressure is 4.0 kPa. Several peak frequencies obtained from the FFT analysis, as the fundamental frequency f ₀ of the lowest frequency to be measured and compared with the supply pressure and flow rate. In addition, the peak seen for every 50 Hz in the lower graph of FIG. 5 originates in power supply noise. In the measurement, the pressure was increased by 0.5 kPa by referring to the display value of the air pressure sensor 56, data was recorded for 4 seconds each time, and three times were tried.

  FIG. 6 shows the relationship among the measured drive pressure, air flow rate, and sound pressure level. There is a tendency that the plot points of the generated sound frequency are slightly scattered, but the plot points are generally controlled in proportion to the driving pressure. Further, the frequency changed around about 175 kHz, and the effect of mixing tungsten powder was as expected. The frequency fluctuation range was less than the original target value of 1 octave (twice the frequency ratio). The driving pressure at the time of continuous voice generation was about 2 to 5 kPa, which was slightly higher than the expiratory pressure at the time of human generation of about 0.5 to 2 kPa.

  The artificial larynx 1 of the present embodiment exhibits good characteristics with respect to pitch, its controllability, volume, and air flow rate, and adopts a simple structure and a simple vibration form, so that foreign substances and moisture during actual use are used. It is excellent in terms of prevention of mixing, and has excellent practicality as an implantable artificial larynx capable of inflection control.

  Thus, in this embodiment, corresponding to claim 1, in the artificial larynx 1 provided in the airway and through which exhalation passes, the cylinder 2 as the main body having the insertion hole 4 for introducing exhalation and the insertion hole 4 are moved. The piston 3 that can be inserted and moved to one side by the expiratory pressure, the outflow hole 8 that communicates the insertion hole 4 with the outside on the other side of the piston 3, and vibrates due to the exhaled air that has flowed out of the outflow hole 8. 3 is provided with an elastic vibrating membrane 11 whose tension is changed by movement to one side, and when exhalation is introduced into the insertion hole 4, the piston 3 is pushed to one side by the pressure, and the elastic vibrating membrane 11 is extended. Then, exhaled air passes through the outflow hole 8 and vibrates the elastic vibrating membrane 11. In this way, the piston 3 receives the expiratory pressure and is pushed to one side, and stops at a position that balances with the tension of the elastic vibration member film 11, and the vibration of the elastic vibration member film 11 changes depending on the tension and the length, particularly the tension. Thus, the frequency can be changed by the expiratory pressure. Therefore, the inflection control can be easily performed by changing the expiratory pressure.

  In this way, in this embodiment, since the elastic vibration member film 11 is provided so as to cover the outflow hole 8 in correspondence with the second aspect, exhalation passes through the outflow hole 8 and becomes the elastic vibration member film 11 and the main body. The elastic vibrating membrane 11 can be vibrated when a gap is created between the cylindrical body 2 and the cylindrical body 2 flows out.

  In this way, in this embodiment, corresponding to claim 3, the opening 4K communicating with the outside is provided on one side of the insertion hole 4, and the elastic vibrating membrane 11 is provided in the opening 4K. The piston 3 moves to one side from the opening 4K by the expiratory pressure, and tension can be applied to the elastic vibration member film 11 provided in the opening 4K.

  Further, in this embodiment, in correspondence with the fourth aspect, since the powder having a specific gravity larger than that of the elastic vibration film 11 is mixed in the elastic vibration film 11, the elastic vibration film is lengthened from the use conditions. Although difficult, it is possible to increase the linear density of the elastic vibration member film 11 by mixing powder having a large specific gravity, and to reduce the natural frequency. In this case, the powder is not limited to a metal as long as the specific gravity is large, but may be a stable carbide such as tungsten carbide or ceramic.

  In this way, in this embodiment, corresponding to claim 5, the powder is tungsten powder, so that tungsten has a large specific gravity and is chemically stable, so that it is suitable for use.

  A second embodiment of the present invention will be described below with reference to FIGS. In addition, the same code | symbol is attached | subjected to the same part as the said Example 1, the detailed description is abbreviate | omitted and explained in full detail. As shown in the figure, the artificial larynx 21 includes a cylindrical body 22 and a piston 23 slidably inserted into the cylindrical body 22. An insertion hole 24 for inserting the piston 23 is provided on one side in the length direction in the cylindrical body 22, and an opening portion 24 </ b> K is provided on one side of the insertion hole 24. An exhalation introduction hole 25 communicating with the insertion hole 24 is provided on the other side in the direction.

  A flat surface 26 is formed on one side of the cylindrical body 22 in the radial direction. The exhalation introduction hole 25 has a circular shape, the exhalation introduction hole 25 is larger than the insertion hole 24, and a step portion 27 is formed between the exhalation introduction hole 25 and the insertion hole 24. The insertion hole 24 has a shape in which a semicircular arc inner surface 24A and a flat inner surface 24B substantially parallel to the flat portion 26 are connected by curved inner surfaces 24C and 24C. In addition, an outflow hole 28 that penetrates the inside and outside of the cylindrical body 22 is provided at the approximate center in the length direction of the insertion hole 24.

  The piston 23 has a shape in which a semicircular arc outer surface 23A and a flat outer surface 24B corresponding to the flat portion 26 are connected by curved outer surfaces 23C and 23C, and the outer shape corresponds to the shape of the insertion hole 24. Yes. Further, the piston 23 is formed with a communication groove 29 that communicates the exhalation introduction hole 25 and the outflow hole 28, and the communication groove 29 is opened on one side in the longitudinal direction of the piston 3 to open the exhalation introduction hole. 25, and the other side in the length direction is closed by a closing portion 29A. As shown in FIG. 8, the communication groove 29 has a square cross section and communicates with the exhalation introduction hole 25. The position where the piston 23 contacts the stepped portion 27 is the initial position of the piston 23, and the communication groove 29 communicates with the outflow hole 28 at the initial position.

  The artificial larynx 21 includes the elastic vibrating membrane 11 that covers the outside of the outflow hole 28, and the elastic vibrating membrane 11 has one end 11 </ b> A bonded to one side of the flat portion 26 from the position of the outflow hole 8. The other end 11B is fixed to one side surface 23M of the piston 23 by adhesion or the like, and the end 11A and the other end 11B are not fixed.

  Next, the mixing effect of tungsten, which is a metal powder, will be described with reference to FIGS. FIG. 10 shows the relationship between the driving pressure and the frequency, and shows the case of “fixed” in which the piston 23 is fixed at the initial position and the case of “movable” in which the piston 23 is slidable. It can be seen that the frequency increases as the driving pressure increases. For both “fixed” and “movable”, the elastic vibrating membrane 11 is 0.5 mm thick and 22 wt% tungsten powder is mixed. FIG. 11 shows a structure in which the piston 23 is movable and the mixing amount of tungsten powder is changed. The elastic vibration member film 11 has a thickness of 0.5 mm, and the mixing amount of tungsten powder is 0 wt% and 2 wt% from the top. , 12 wt%, 22 wt%. From this graph, it was confirmed that the frequency decreased as the mixing amount of tungsten powder increased.

  Therefore, when exhalation is introduced from the exhalation introduction hole 25, the piston 23 is pushed to one side by the pressure, the elastic vibrating membrane 11 extends, the exhalation passes through the outflow hole 28, and the elastic vibrating membrane 11, the cylindrical body 22, The elastic vibrating membrane 11 vibrates when a gap is formed between the two and the fluid flows out to the outside.

  Thus, the exhaled air guided from the exhalation introducing hole 25 passes through the communication groove 29 of the piston 3 and is discharged from the outflow hole. Although the outflow hole 28 is closed by the elastic vibrating membrane 11 when not in operation, a gap is formed between the flat surface 26 by applying exhalation pressure. At this time, the elastic vibrating body, which is an elastic body, is formed. It vibrates due to the relationship between the restoring force of the membrane 11, the expiratory pressure, and the expelling fluid force (Bernoulli force), and it becomes a sound source by intermittently circulating and blocking the exhaled breath. The elastic vibration member film 11 is fixed to the cylindrical body 22 and the piston 23 by adhesion or the like at both end portions 11A and 11B, respectively. In a state where no expiratory pressure is applied, the piston 23 abuts against the stepped portion 27 and stops. However, when the expiratory pressure is applied, the piston 23 slides to a position that matches the longitudinal tension of the elastic vibrating membrane 11 and stops. To do. Therefore, the tension in the major axis direction of the elastic vibrating membrane 11 changes in proportion to the pressure of exhalation causing vibration, and therefore the vibration frequency also changes in proportion to the expiratory pressure (actually, the tension It is proportional to the square root, but it can be regarded as almost linear in the actual usage range). As a result, the user can easily add inflection to the voice by consciously and unconsciously changing the expiratory pressure.

  Thus, as a means for a larynx extractor to obtain a substitute sound after the operation, an artificial larynx 21 as a one-way valve is provided on the tracheal wall esophagus side, and when the exhalation is guided to the esophagus, the artificial larynx 21 is driven by exhalation. By incorporating a sound source and inducing a sound source frequency change according to the expiratory pressure, it is possible to add inflection to the sound according to the user's intention.

  The artificial larynx 21 of the present invention has a small number of parts, can be manufactured at low cost, and itself has a one-way valve function, so that inflow of food and drink, saliva, body fluid and other secretions in daily life, etc. It is also extremely functionally robust.

  In addition, the elastic vibrating membrane 11 serving as a sound source can be adjusted in density at the time of production by mixing, for example, tungsten powder having a specific gravity of about 19, and an appropriate pitch can be selected regardless of age or sex. Further, even if a tungsten powder having a particle size of 1 to 3 μm, preferably 2 μm, is mixed in silicone rubber by about 1% to more than 20%, the elastic modulus is hardly affected.

  A conventional sound source with a built-in TE shunt valve must be extremely small, and it is not easy to obtain a desired frequency. Moreover, since it is calculated | required to operate | move stably even when there exists inflow of saliva, a bodily fluid, and food and drinks, a structure must be simple. The artificial larynx 21 of this embodiment can satisfy these requirements at a high level. That is, the component is composed of only three points of the cylindrical body 22, the piston 23, and the elastic vibration body film 11, and has a simple structure. Therefore, the manufacturing is easy and inexpensive, and the elastic vibration body film 11 that is a sound source. Acts as a one-way valve for exhaled air, and even if any inflow is mixed, it can be naturally eliminated by exhaled air. Although the piston is provided as the only movable part, even if the piston 23 is fixed for some reason, the utterance function is not lost. Further, although tungsten powder is used for the purpose of increasing the mass of the elastic vibration member film 11, it seems that the toxicity of tungsten itself to the human body is not recognized. Furthermore, since the voice height can be adjusted by changing the mixing ratio of the tungsten powder at the time of producing the elastic vibration film 11, it is easy to obtain a voice of a desired height regardless of gender or age.

  Thus, in the present embodiment, corresponding to claim 1, in the artificial larynx 21 provided in the airway and through which exhalation passes, the cylinder 22 as the main body having the insertion hole 24 for introducing exhalation and the insertion hole 24 are moved. The piston 23 that is inserted and moved to one side by the expiratory pressure, the outflow hole 28 that communicates the insertion hole 24 with the outside on the other side of the piston 23, and vibrates due to the exhaled air that has flowed out of the outflow hole 28. 23, the elastic vibrating membrane 11 whose tension is changed by movement to one side is provided, and thus the same operations and effects as the first embodiment are obtained.

  The present invention is not limited to this embodiment, and various modifications can be made within the scope of the gist of the present invention. For example, the elastic vibrating membrane is not limited to the embodiment, and various types can be used as long as they have elasticity and vibrate. The artificial larynx is not limited to the implantable type, and may be used outside the body.

DESCRIPTION OF SYMBOLS 1 Artificial larynx 2 Cylindrical body 3 Piston 4 Insertion hole 8 Outflow hole 11 Elastic vibration body film | membrane 11A One end 11B Other end 21 Artificial larynx 22 Cylindrical body 23 Piston 24 Insertion hole 28 Outflow hole

Claims (5)

In an artificial larynx through which exhalation passes, a main body having an insertion hole for introducing exhalation, a piston that is movably inserted into the insertion hole and moves to one side by exhalation pressure, and an outflow hole that communicates the insertion hole with the outside And an elastic vibrating membrane that vibrates due to exhaled air that has flowed out of the outflow hole and that changes in tension due to movement toward one side of the piston. The artificial larynx according to claim 1, wherein the elastic vibrating membrane is provided so as to cover the outflow hole. The artificial larynx according to claim 1, wherein an opening portion communicating with the outside is provided on one side of the insertion hole, and the elastic vibrating membrane is provided in the opening portion. The artificial larynx according to any one of claims 1 to 3, wherein powder having a specific gravity greater than that of the elastic vibrating membrane is mixed in the elastic vibrating membrane. The artificial larynx according to claim 4, wherein the powder is tungsten powder.

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