JP5980049B2 - Silencer and method for adjusting amplitude of diaphragm - Google Patents

Description

  The present invention relates to a silencer applied to a human ear and an amplitude adjusting method for a diaphragm portion thereof.

  2. Description of the Related Art Conventionally, earplugs for blocking external noise have been disclosed that are inserted into the external auditory canal using a plastic material (for example, Patent Documents 1 and 2).

Also, external noise is input as an electrical signal using an electronic circuit, and the sound wave of the noise is canceled by outputting a signal in the opposite phase to that, so that only unnecessary noise is selectively blocked (so-called noise canceller) Is also disclosed (for example, Patent Document 3).
What is silenced using an electronic circuit in this way is not limited to earplugs, but to noise or noise generated from an exhaust port or a cooling fan, or to a magnetic resonance imaging apparatus (MRI apparatus) that generates large noise. Those have already been disclosed (for example, Patent Documents 4 and 5).

  Furthermore, two opposing diaphragms fixed to the frame are connected by a mechanical anti-phased vibration transmission mechanism, and the vibration of one diaphragm is mechanically reversed into a vibration having an opposite phase to the other diaphragm. A silencing wall is also disclosed that exhibits a silencing effect by transmitting to (for example, Patent Document 6).

Japanese Patent No. 4047162 Japanese Patent Laid-Open No. 11-000357 JP 2008-099163 A JP-A-2005-234203 JP 2005-152420 A Japanese Patent No. 3136562

  However, although the earplugs of Patent Documents 1 and 2 are useful with a simple configuration, the sound that has passed through the earplug itself cannot be blocked, and it is extremely difficult to create a completely sound-insulated state.

  In addition, the noise canceling headphone disclosed in Patent Document 3 uses an electronic circuit, which complicates the device and becomes expensive, and consumes extra power to operate the circuit. The same applies to the configurations disclosed in Patent Documents 4 and 5.

  Furthermore, at the time of examination using an MRI apparatus, it is common for a user to wear an earplug. However, since the MRI apparatus generates a strong electromagnetic field, the user cannot basically wear metals to avoid disturbing the inspection. Therefore, in the end, the earplugs as described in Patent Documents 1 and 2 had to be used.

  Furthermore, the sound deadening wall described in Patent Document 6 is premised on that the surface area of one diaphragm and the other diaphragm is the same, and the vibration of one diaphragm is changed to the vibration of the other diaphragm. Due to energy attenuation due to friction or the like of the mechanical anti-phase vibration transmission mechanism that transmits the vibration, the vibration of the diaphragm shifts with respect to the sound wave vibration of the noise, and there is a problem that the silencing effect is reduced.

  Therefore, an object of the present invention is to provide a silencer that can be suitably silenced and can be used for diagnosis using, for example, an MRI apparatus without relying on an electronic device, with a configuration as simple as possible.

  The present invention is a silencer that is applied to a human ear, and includes a cylindrical silencer main body, and the silencer main body has an inner part disposed on the eardrum side of the ear and a diameter expanding from the inner part. And an outer portion that extends along the cylinder axis direction of the inner portion, and is disposed on the outside side, and a diaphragm portion is provided so as to cover the opening of the inner portion, and the inner portion A sound collecting plate portion is provided so as to cover the opening of the outer portion having a larger area than the opening of the inner portion, and the inner space portion of the silencer body is set to be orthogonal to the cylinder axis direction of the inner portion. A lever shaft that is rotatably attached to the side wall of the silencer body, and extends from the lever shaft toward the sound collecting plate, and an end thereof is fixed to the sound collecting plate. A sound collecting plate side rod portion, and a diaphragm portion side rod portion extending from the lever shaft portion toward the vibrating plate portion and having an end portion fixed to the vibrating plate portion. When the sound collecting plate portion is vibrated by sound waves, the vibration transmitting lever member rotates about the lever shaft portion when the sound collecting plate portion vibrates. Thus, the muffler is characterized in that the diaphragm portion vibrates in a phase opposite to that of the sound collecting plate portion.

  In such a configuration, the external sound first vibrates the sound collecting plate portion. When the sound collecting plate portion vibrates, the vibration transmitting lever member connected to the sound collecting plate portion rotates about the lever shaft portion to vibrate the diaphragm portion. At this time, the vibration plate portion vibrates in a phase opposite to that of the sound collection plate portion. That is, when the sound collecting plate portion side rod portion and the vibration plate portion side rod portion are interlocked with each other, the sound collecting plate portion and the vibration plate portion vibrate in opposite directions, and are emitted in the outside world. The sound wave and the pressure wave formed by the vibration of the vibration plate portion cancel each other, and thereby the external sound is suitably muted.

  By the way, it is conceivable that the vibration of the diaphragm portion is smaller than the vibration of the external sound due to the frictional resistance generated when the lever shaft portion is rotated. However, since the area of the diaphragm portion is smaller than that of the sound collecting plate portion, even if the vibration of the diaphragm portion becomes smaller than the vibration of the external sound for the above reason, the diaphragm portion vibrates with sufficient amplitude. An appropriate antiphase wave can be generated. In addition, the present invention has a configuration in which the diaphragm portion is vibrated using the so-called lever principle, so that no electronic circuit is required, and all the constituent materials can be made of nonmetal (synthetic resin or the like). For this reason, for example, it can be used even during use of an MRI apparatus that cannot wear metal.

  In addition, a through portion through which the sound collecting plate portion side rod portion is inserted is provided between the lever shaft portion of the vibration transmission lever member and the sound collecting plate portion, which is an inner space portion of the silencer body. It is desirable that a shield plate is provided.

  With this configuration, since the sound (vibration) that has passed through the sound collecting plate portion is partially shielded by being reflected or absorbed by the shielding plate, the area of the vibration plate portion is the sound collecting plate portion. A sufficient silencing effect can be expected even if it is smaller than the area.

  An opening penetrating the side wall may be provided on the side wall of the silencer body corresponding to the position where the shielding plate is disposed.

  By adopting such a configuration, the sound (vibration) that has entered the inside of the silencer body and the sound (vibration) reflected by the silencer body or the shielding plate go to the outside from the opening, so the silencer body The sound (vibration) that passes through the inner space in the direction of the diaphragm is limited. For this reason, even if the area of the diaphragm portion is smaller than that of the sound collecting plate portion, a sufficient silencing effect can be expected. Further, even when a pressure fluctuation occurs around the shielding plate when external sound (vibration) is reflected or absorbed by the shielding plate, the pressure fluctuation is preferably relaxed through the opening to It is possible not to disturb the silencing effect.

  Furthermore, it is desirable that the cylinder axis on the outer side of the silencer body is eccentric with respect to the cylinder axis on the inner side, and the cylinder axis on the inner side does not pass through the center of the sound collecting plate part. .

  By adopting such a configuration, for example, when the silencer is used as an earplug, the sound collecting plate portion side is directed to the outside, and the diaphragm portion side is directed to the eardrum side, the tube axis line at the outer portion and the tube axis line of the inner portion. Therefore, the silencer body can be more closely attached to the inner peripheral surface of the user's ear, and the silencing effect can be further improved.

  Further, the present invention provides the above silencer, wherein the position of the lever shaft portion of the vibration transmitting lever member relative to the sound collecting plate portion and the vibration plate portion is changed, thereby accompanying the vibration of the sound collecting plate portion. Then, the amplitude adjustment method of the diaphragm part in the silencer is characterized by adjusting the amplitude when the diaphragm part vibrates.

  Thus, by adjusting the position of the lever shaft portion of the vibration transmission lever member and changing the overall length of the rod portion, etc., the vibration can be obtained so as to obtain the most excellent silencing effect against external noise. The plate portion can be vibrated.

  The silencer of the present invention does not use an electronic device or the like, and therefore does not need to use electric power, and can exhibit a silencing effect far superior to a silencer such as a conventional earplug. Furthermore, by using a resin material or the like, it is not necessary to use metal, and it can be used even in situations where it is impossible to wear metal (for example, during diagnosis using an MRI apparatus).

  Moreover, the amplitude adjustment method of the present invention can provide a silencer that can obtain the most effective silencing effect according to the use conditions.

BRIEF DESCRIPTION OF THE DRAWINGS It is a silencer concerning Example 1, Comprising: (a) is a front view, (b) is a side view, (c) is a longitudinal cross-sectional view. Explanatory drawing for demonstrating the structure of the silencer concerning Example 1. FIG. The schematic diagram of the experiment for confirming the silencing effect. It is a silencer concerning Example 2, Comprising: (a) is a front view, (b) is a side view, (c) is a longitudinal cross-sectional view. It is a silencer concerning Example 3, Comprising: (a) is a front view, (b) is a side view, (c) is a longitudinal cross-sectional view. The perspective view of the headset provided with the silencer concerning Example 4. FIG. Sectional drawing of the earpiece part of the headset provided with the silencer concerning Example 5. FIG.

  Hereinafter, embodiments embodying the silencer of the present invention will be described in detail. In addition, this invention is not limited to the Example shown below, A design change is possible suitably.

[Example 1]
In order to confirm the silencing effect of the silencer applied to the human ear, a silencer 1A as an experimental model was created. 1 and 2 show a silencer 1A.

  The silencer 1 </ b> A includes a cylindrical silencer body 2. The silencer body 2 is arranged on the outer side, which is extended along the cylindrical axis direction of the inner part 3 so as to expand from the inner part 3 and the inner part 3 on the ear drum side. The outer portion 4 is provided. The outer portion 4 includes a tapered portion 4a that is continuous with the inner portion 4, and a straight pipe portion 4b that extends from the tapered portion 4a.

  A thin sound collecting plate portion 5 is disposed on the outer side portion 4 of the silencer body 2 so as to cover the opening. Furthermore, a thin plate-like diaphragm portion 6 is disposed on the inner side portion 3 of the silencer body 2 so as to cover the opening. The sound collecting plate 5 is dimensioned so as to have a larger area than the diaphragm 6. Further, the sound collecting plate portion 5 and the vibration plate portion 6 are obliquely oriented so as not to be orthogonal to the cylinder axis of the inner portion 3 of the silencer body 2.

  Further, a vibration having a lever shaft portion 7 which is set in the inner space portion of the silencer body 2 so as to be orthogonal to the cylinder axis direction of the inner portion 3 and is rotatably attached to the side wall of the outer portion 4. A transmission lever member 8 is provided. More specifically, the vibration transmission lever member 8 extends from the lever shaft portion 7 toward the sound collecting plate portion 5, and the end portion thereof is fixed to the sound collecting plate portion 5. A rod portion 8a is provided. Further, a vibration plate side rod portion 8 b that extends from the lever shaft portion 7 toward the vibration plate portion 6 and has an end portion fixed to the vibration plate portion 6 is also provided.

  Furthermore, a shield plate 9 is provided in the inner space of the silencer body 2. The shield plate 9 is provided with a through-hole 9 a formed in a through hole for allowing the sound collecting plate-side rod portion 8 a to pass therethrough. ing. Specifically, the shielding plate 9 is configured in a shape that decreases in diameter toward the sound collecting plate portion 5. Further, a plurality of apertures 10 are provided in a penetrating manner on the side wall of the outer portion 4 corresponding to the position where the shielding plate 9 is disposed. In addition, the said penetration part 9a may be comprised by the notch part.

  In the above configuration, as shown in FIG. 2a, when the sound collecting plate portion 5 vibrates due to a sound wave generated outside, the sound collecting plate portion side rod fixed to the sound collecting plate portion 5 along with this. The portion 8a is interlocked with the axial direction, and as a result, the vibration transmission lever member 8 is rotated around the lever shaft portion 7 as shown in FIG. 2b. If it does so, the said diaphragm part side rod part 8b will interlock | cooperate with the axial direction, and the said diaphragm part 6 will vibrate with the phase opposite to the said sound-collecting board part 5. FIG.

  Thereby, the sound wave emitted in the external environment and the pressure wave formed by the vibration of the vibration plate portion 6 cancel each other, whereby the external sound is suitably muted.

In this embodiment, as the silencer 1A, the silencer body 2 is a vinyl chloride tube.
A speaker cone having a diameter of 50 mm was used as the sound collecting plate section 5, and a speaker cone having a diameter of 20 mm was used as the diaphragm section 6.
As the vibration transmission lever member 8, a molded product made of a thermoplastic resin material was used.
As the shielding plate 9, a truncated cone shaped product made of a thermoplastic resin material was used.

  In the present embodiment, the area ratio between the sound collecting plate portion 5 and the diaphragm portion 6 is 6.25: 1. As shown in FIGS. 2A and 2B, depending on the area ratio between the sound collecting plate portion 5 and the vibration plate portion 6 or the relative position of the lever shaft portion 7 with respect to the sound collecting plate portion 5 and the vibration plate portion 6. The vibration β having the optimum opposite phase to the vibration α picked up by the sound collecting plate portion 5 can be generated.

  Further, most of the vibration that has passed through the sound collecting plate portion 5 is reflected by the shielding plate 9, is directed from the opening 10 toward the outside z, and only the vibration that has passed through the through portion 9 a of the shielding plate 9 is the vibration plate 6 portion. I will head to the side.

  In order to confirm the silencing effect of the silencer 1A, a test as schematically shown in FIG. 3 was performed. That is, the silencer 1A is inserted into a pipe P made of vinyl chloride having a predetermined inner diameter, a sound wave is emitted from the sound collecting plate portion 5 side by the speaker S, and the microphone M is placed on the opposite side of the silencer 1A in the pipe P. It was installed and it was confirmed whether the sound wave detected by the microphone M was attenuated.

  As Comparative Example 1, a silencer from which the vibration transmission lever member 8 was removed was used. Further, as Comparative Example 2, a rubber plug was used instead of the silencer, and this was inserted into the pipe P to perform a confirmation test.

  As a result of the above experiment, it was confirmed that the amplitude was reduced in the case of Example 1. On the other hand, for Comparative Examples 1 and 2, an effective amplitude reduction could not be confirmed. Further, for Example 1, it was confirmed that the diaphragm 6 vibrates in the opposite phase with respect to the sound collector 5 using an oscilloscope.

  The shielding plate 9 may be made of a known sound absorbing material. The same applies to the shielding plate 9 shown in the following embodiments. In addition, when the silencer 1A is used as an earplug, it is preferable to design the external shape of the silencer main body 2 so that the sound collecting plate portion 5 or the diaphragm portion 6 faces an appropriate direction when worn. . Moreover, although the sound-collecting board part 5 may be arrange | positioned at the opening end of the outer side part 4, it is preferable to arrange | position slightly inside this opening end for damage prevention. The same applies to the diaphragm 6. Further, an opening area adjusting means capable of adjusting the opening area may be provided at the opening end of the outer portion 4.

[Example 2]
FIG. 4 shows a silencer 1B used as an earplug.
The reference numerals of the respective parts are the same as those in the first embodiment, and the description of the parts common to the first embodiment is simplified or omitted.

  In the silencer 1 </ b> B, the cylinder axis Y of the outer portion 4 is formed eccentrically with respect to the cylinder axis X of the inner portion 3, and the cylinder axis X of the inner portion 3 corresponds to the sound collecting plate portion 5. The structure does not pass through the center. This makes it easier for the outer portion 4 of the silencer 1B to be in close contact with the inner peripheral surface of the user's ear. In addition, the size and shape of the vibration transmission lever member 8 are optimized, and vibration can be transmitted efficiently.

  Further, the diaphragm 6 is provided obliquely so as not to be orthogonal to the cylinder axis X of the inner part 3 of the silencer body 2, and when the silencer 1B is attached to the ear, the diaphragm 6 Is designed to face the user's eardrum. With such a configuration, a much higher silencing effect can be obtained.

Example 3
A silencer 1C used as an earplug is shown in FIG. The reference numerals of the respective parts are the same as those in the first and second embodiments.

  In the present embodiment, unlike the second embodiment, not only the diaphragm portion 6 but also the sound collecting plate portion 5 are oriented obliquely so as not to be orthogonal to the cylinder axis X of the inner portion 3 of the silencer body 2. Even with this configuration, it is possible to obtain a silencing effect by vibrating the diaphragm 6 with sufficient amplitude.

Example 4
A headset H1 using the silencer 1D is shown in FIG.
In the present embodiment, a silencer 1D is attached to the ear pad 11 of the headset H1. In this case, the inner part 3 of the silencer 1D is not inserted into the ear of the user of the headset H1, and the sound insulating sponge 12 provided on the inner periphery of the ear pad 11 during use is used by the user. Ears will be covered.

  In the present embodiment, a speaker (not shown) may be disposed inside the sound insulating sponge 12 of the ear pad 11 so as to suitably mute external noise.

Example 5
FIG. 7 shows a cross-sectional view of the ear pad 13 of the headset H2 using the silencer 1E of the present embodiment.

  In the present embodiment, the ear pad 13 of the headset H2 is formed in a dome shape by a sound absorbing material, and a hole 14 is provided in a part thereof to constitute the silencer body 2 of the silencer 1E. The silencer body 2 is provided with a sound collecting plate portion 5 and a diaphragm portion 6.

  In addition, the earpiece 13 of the headset H2 is provided with a speaker 15, and the sound output from the speaker 15 can be surely heard by the user, and external noise is suitably silenced by the silencer 1E. The

  Here, the ear contact portion 13 may be formed in a hollow shape using a hard material instead of the sound absorbing material, and the sound absorbing material may be filled in the cavity. In that case, an opening 10 may be provided in the outer portion 4 of the silencer body 2.

  The silencer of the present invention can be used as an earplug, manufactured entirely with synthetic resin so that it can be used even in places where the introduction of metals is prohibited (diagnosis using an MRI apparatus, etc.). In addition, it is possible to provide a very high silencing effect. In addition, since the silencing effect is high, it can be used for a good night's sleep or at a work site where a loud noise is generated, and can be manufactured at low cost.

  Furthermore, the silencers 1A to 1E of the present invention change the position of the lever shaft portion 7 of the vibration transmission lever member 8 with respect to the sound collecting plate portion 5 and the vibration plate portion 6 to thereby change the sound collecting plate portion 5. As a result of the vibration, the amplitude when the diaphragm 6 vibrates can be adjusted, whereby the diaphragm 6 can be brought into an optimum state in which a silencing effect is exhibited.

  The silencers 1A to 1E of the present invention are not limited to the earplugs of the second and third embodiments and the headsets of the fourth and fifth embodiments, and are applied in a form corresponding to the use environment such as a helmet at a work site. Can do.

  In consideration of the efficiency of vibration transmission, the silencer body 2 is preferably made of a hard material, and the sound collecting plate portion 5 and the vibrating plate portion 6 are preferably as thin as possible.

  By the way, the silencers 1A to 1E described so far improve the followability of the diaphragm 6 with respect to the vibration of the sound collecting plate 5 as the weight is reduced. It is also inferred that the sound range in which the silencing effect is exhibited is widened. Therefore, it is considered that the failure due to the resonance phenomenon of the mechanical operation portion (specifically, the sound collecting plate portion 5, the vibration plate portion 6, and the vibration transmission lever member 8) can be ignored as the weight is further reduced. It is done.

1A to 1E Silencer 2 Silencer body 3 Inner part 4 Outer part 5 Sound collecting plate part 6 Vibration plate part 7 Lever shaft part 8 Vibration transmitting lever member 8a Sound collecting plate side rod part 8b Vibration plate part side rod part 9 Shielding Plate 9a Through-hole 10 Opening X, Y Cylinder axis

Claims (5)

A silencer applied to the human ear,
Provided with a cylindrical silencer body, the silencer body,
An inner part arranged on the eardrum side of the ear;
An outer portion that extends along the cylinder axis direction of the inner portion so as to expand from the inner portion,
Have
A diaphragm part is provided so as to cover the opening of the inner part, and a sound collecting plate part is provided so as to cover the opening of the outer part having a larger area than the opening of the inner part,
Furthermore, in the inner space of the silencer body,
A lever shaft that is set to be orthogonal to the cylinder axis direction of the inner portion and is pivotally attached to the side wall of the silencer body;
A sound collecting plate side rod portion extending from the lever shaft portion toward the sound collecting plate portion and having an end portion fixed to the sound collecting plate portion;
A diaphragm portion side rod portion extending from the lever shaft portion toward the diaphragm portion and having an end portion fixed to the diaphragm portion;
A vibration transmission lever member having
When the sound collecting plate portion is vibrated by sound waves, the vibration transmitting lever member rotates around the lever shaft portion along with the vibration of the sound collecting plate portion, so that the vibration plate portion is moved to the sound collecting portion. A silencer that vibrates in the opposite phase to the plate. A through portion through which the sound collecting plate portion side rod portion is inserted is provided between the lever shaft portion of the vibration transmission lever member and the sound collecting plate portion, which is an inner space of the silencer body. The silencer according to claim 1, wherein a shielding plate is provided. The silencer according to claim 2, wherein an opening penetrating the side wall is provided on a side wall of the silencer body corresponding to a position where the shielding plate is disposed. The cylinder axis of the outer part of the silencer body is eccentric with respect to the cylinder axis of the inner part, and the cylinder axis of the inner part does not pass through the center of the sound collecting plate part. The silencer according to any one of claims 3 to 4. The silencer according to any one of claims 1 to 4, wherein the position of the lever shaft portion of the vibration transmission lever member with respect to the sound collecting plate portion and the diaphragm portion is changed. A method for adjusting an amplitude of a diaphragm part in a silencer, wherein the amplitude when the diaphragm part vibrates with the vibration of the sound collecting part is adjusted.

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