JP3549065B2 - Sound collector vibration isolator - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a vibration isolator for a sound collector. More specifically, it collects solid sounds that transmit low and high-pitched noise to solid parts of resin and metal through the support base that supports the sound collector, and the casing of the recording / recording device that contains the sound collector. The present invention relates to a vibration isolator of a sound collector for preventing a sound device from being picked up.
[0002]
[Prior art]
A high-performance sound collector placed on the conference desk reliably picks up noise generated by the desk through the resin / metal solid part of the sound collector body. The sound collector incorporated in the recording / recording device surely picks up noise picked up by the casing of the recording / recording device through the solid resin / metal portion of the sound collector main body. It is known that a sound collector is supported on a support base or casing via a vibration isolating / attenuating means such as a vibration isolating rubber or a spring, thereby making it difficult to pick up external noise.
[0003]
[Problems to be solved by the invention]
However, those that make it difficult for external noise to be picked up by supporting the sound collector on the support base or casing via anti-vibration and damping means such as anti-vibration rubber and spring High-frequency noise is transmitted through a semi-solid or solid body and reaches the main body.
[0004]
The present invention has been made under the above-mentioned technical background, and achieves the following objects.
[0005]
An object of the present invention is to use a vibration damping / attenuating means for a liquid to which external sound is difficult to transmit so that external noise and noise generated by a device storing the same are not transmitted to the sound collecting unit of the sound collector. To provide an anti-vibration device for a sound collector.
[0006]
Another object of the present invention is to provide an inexpensive vibration isolator for a sound collector.
[0007]
[Means for Solving the Problems]
The present invention employs the following means to achieve the above object.
[0008]
The vibration isolator of the sound collector according to the first aspect of the present invention includes:
A sound collector main body (25) having a sound collecting means having a sound collecting function therein is held at the center, and has a closed cavity surrounding the outer periphery of the sound collector main body (25) and is formed of a resin elastomer. An elastic cavity forming body (11);
A vibration damping liquid (17) sealed in the closed cavity of the elastic cavity forming body (11) for damping vibration;
A vibration isolator for a sound collector, comprising: a vibration isolator main body (1) holding the elastic cavity forming body (11) at a central portion and surrounding an outer peripheral portion of the elastic cavity forming body (11);
The elastic cavity forming body (11) is interposed between the elastic cavity forming body (11) and the sound collector body (25), and is integrally connected to an inner portion of the elastic cavity forming body (11). ) Comprises an axial support (21) for supporting the sound collector body (25) in the axial direction of the central axis.
[0009]
The vibration isolator of the sound collector according to the second aspect of the present invention,
The elastic cavity forming body (11) is formed in an annular shape so that the cavity is annular, and is formed so as to hold an outer peripheral surface (26) of the sound collector body (25). The outer peripheral surface (22) of the elastic cavity forming body (11) is in contact with and joined to the inner peripheral surface (5) of (1).
[0010]
The vibration isolator of the sound collector according to the third aspect of the present invention is the same as the first aspect,
The elastic cavity forming body (11) is formed in an annular shape so that the cavity is annular, the sound collector body (25) is formed to have an outer peripheral surface (26), and the vibration isolator body (11) is formed. The outer peripheral surface of the elastic cavity forming body (11) is inscribed in the inner peripheral surface (5) provided in 1), the axial support (21) is annular, and the outer peripheral surface of the axial support (21) is provided. Are inscribed in the inner peripheral surface of the elastic cavity forming body (11).
[0012]
[Action]
In the vibration isolator of the sound collector according to the present invention, sound waves transmitted at the interface between the elastic bag and the liquid disappear and attenuate. Sound waves transmitted through the liquid in the elastic bag made of a soft rubber-like material are attenuated, and high-frequency components are attenuated. The sound collector body is suspended by the elastic bag. There is no resonance between the sound collector body and the external environment. The bass component does not propagate to the sound collector body.
[0013]
【Example】
(Example 1)
Next, examples of the present invention will be described. FIG. 1 is a sectional view showing Embodiment 1 of a vibration isolator of a sound collector according to the present invention. The vibration damping device main body 1 shown in FIG. 1 is attached to a sound collector support stand (not shown) placed on a desk, or attached to a main body casing 2 of a video device with screws 3. In some cases, the vibration isolator main body 1 and the main body casing 2 are integrally formed by injection molding. For the vibration isolator main body 1, a resin having high mechanical strength and good moldability, such as ABS resin, polycarbonate, PP, PBT, nylon 6, 11, 12, or the like, so-called engineering plastics can be used.
[0014]
The vibration isolator main body 1 has a cylindrical mounting portion 4 at the center. The cylindrical mounting portion 4 has a cylindrical inner peripheral surface 5. An elastic support 7 is joined to the cylindrical mounting portion 4 in contact with the annular end surface 6 of the cylindrical mounting portion 4. The elastic support 7 includes an annular surface 8 that is in contact with and contacts the annular end surface 6 of the cylindrical mounting portion 4 and an inner peripheral surface 10 that is bonded to the outer peripheral surface 9 of the cylindrical mounting portion 4.
[0015]
For the elastic support 7, various soft or hard thermoplastic elastic materials can be used. Various elastomers can be used as the thermoplastic elastic material. Such a thermoplastic elastic material is selected from, for example, nylon elastomer, polyurethane elastomer, polyester elastomer, and the like. In particular, for the material selected from the engineering plastics, a soft or hard elastic material having heat-fusibility is selected. The cylindrical mounting portion 4 and the elastic support 7 can be thermally fused by one-piece injection molding. The resin on the other side is re-melted by the heat of the molten resin at the time of one-piece molding and fuses with each other to form one.
[0016]
An annular sound absorbing cushioning bag 11 is provided inside the cylindrical mounting portion 4 as an elastic cavity forming body. The sound absorbing buffer bag 11 includes an outer peripheral wall 12, an inner peripheral wall 13, an annular outer wall 14 bulging outward, and an annular sealing lid 15 described later. For the sound absorbing buffer bag 11, the soft elastomer is used. The thickness is about 0.5 mm. The outer peripheral wall 12, the inner peripheral wall 13, and the annular outer wall 14 can be produced by injection molding.
[0017]
The sound absorbing buffer bag 11 forms a closed space inside. A vibration damping material 17 is sealed in an annular cavity 16 which is a closed space. Various silicone oils can be used as the vibration damping material 17. In this case, a material having a high viscosity is used. As the vibration damping material 17, for example, silicon having a viscosity of about 10,000 to 50,000 centipoise is used. As the vibration damping material 17, various foams having a high foaming rate and impregnated with silicone oil can be used. As the material of the foam, a nylon elastomer, a polyurethane elastomer, a polyester elastomer, or the like can be used.
[0018]
An axial support 21 is inscribed and joined to the inner peripheral surface of the inner peripheral wall 13 of the sealing lid 15. The outer peripheral surface 22 of the outer peripheral wall 12 of the sound absorbing buffer bag 11 is in contact with the inner peripheral surface of the cylindrical mounting portion 4. The axial support 21 is interposed between the sound-absorbing buffer bag 11, which is an elastic cavity forming body, and a main body of a sound collector described later.
[0019]
The axial support 21 is annular and has a central axis L. The sound collector main body 25 is inserted inside the sound absorbing buffer bag 11. The sound collector main body 25 has an outer peripheral surface 26. In this case, it is a cylindrical outer peripheral surface. The outer peripheral surface 26 of the sound collector main body 25 is in contact with the inner peripheral surface of the sound absorbing buffer bag 11.
[0020]
The small-diameter outer peripheral surface of the sound collector main body 25 is in contact with the inner peripheral surface of the axial support 21. The sound collector main body 25 includes a sound collecting means including a known vibrator (not shown) or the like inside. The vibrator is supported by the sound collector main body 25 so as to freely vibrate. Since the vibrator and other common means for sound collection and recording are well known, their description is omitted.
[0021]
Next, an example of an assembling method of the vibration isolator main body 1, the sound absorbing buffer bag 11, the elastic support 7 and the axial support 21 by injection molding will be described. FIG. 2 shows a first assembly process. A relatively movable mold element 30, 31 is used. The anti-vibration device main body 1 produced by molding in another process is inserted into one of the mold elements 30 and 31.
[0022]
The mold element 31 has an annular mold element portion 32 corresponding to a cavity 34 formed by the outer peripheral wall 12, the inner peripheral wall 13, and the annular outer wall 14. Elastomer resin is injected into the cavity 33 formed by the mold element 30, the mold element 31, and the vibration isolator main body 1 from the runner and the gate 34 formed in the mold element 30.
[0023]
FIG. 3 shows the next second assembling step. A mold element 38 having an annular projection 37a that partially or entirely fits into a cavity 36 of a semifinished product 35 including the outer peripheral wall 12, the inner peripheral wall 13, the annular outer wall 14, and the vibration isolator main body 1 is used. A mold element 40 facing the mold element 38 and movable relative to the mold element 38 is used.
[0024]
A cavity 41 corresponding to the axial support 21 is formed by the mold element 40, the mold element 38, and the semi-finished product 35. Mold elements 42, 42 movable in a direction orthogonal to the movable direction of the mold element 40 are used. The mold elements 42, 42, the mold element 38 and the semi-finished product 35 form a cavity 43 corresponding to the elastic support 7. The cavities 41 and 43 can be made into one by a plurality of connecting cavities without making them independent cavities.
[0025]
Elastomer resin is injected into the cavities 41 and 43 from the runners and gates 44 and 45 formed in the mold element 38. The vibration damping material 17 is put into the cavity 34 of the second semi-finished product produced in the second assembly process, as shown in FIG. The sealing lid 20 produced in another process is pressed into the open end of the cavity 34. This press-fitting employs a method similar to the method described in JP-A-4-157691. The sealing lid 15 and the sound-absorbing buffer bag 11 are heat-sealed by a known heat-sealing means such as high-frequency heating to be integrated. As described above, the sound absorbing buffer bag 11, the elastic support 7, the sealing lid 20, and the axial support 21 are integrated by thermal fusion.
[0026]
Next, the operation of the above embodiment will be described. The vibration isolator main body 1 is attached to a casing of an electronic device such as a video device. Alternatively, it is fitted into a support base body placed on a desk. The casing of the video equipment is fixed to a shooting footrest that is placed on a person's shoulder or placed on the ground. Hard sound (high sound) is transmitted to the main body casing 2 via the desk, the shoulder of the person, and the footrest for photographing.
[0027]
This sound wave is transmitted to the vibration isolator main body 1. The sound wave transmitted to the vibration isolator main body 1 is propagated to the elastic support 7. The elastic support member 7 made of an elastomer and the cylindrical mounting portion 4 of the vibration isolator main body 1 have different natural frequencies, so that they do not easily resonate with each other. Therefore, the sound wave propagated to the cylindrical mounting portion 4 is not easily transmitted to the elastic support 7.
[0028]
The sound wave transmitted to the elastic support 7 is transmitted through the sealing lid 15 of the sound absorbing cushioning bag 11, and the sound wave transmitted to the cylindrical mounting portion 4 is transmitted through the outer peripheral wall 12 of the sound absorbing cushioning bag 11. Is transmitted to. The sound wave propagated to the vibration damping member 17 is absorbed and attenuated by the vibration damping member 17 having high viscosity and easily absorbing various frequencies.
[0029]
Particularly, hard sound is absorbed and attenuated, and the sound wave propagating to the sound collector main body 25 is only a small part. Further, since the sound collector main body 25 is elastically supported by the sound absorbing buffer bag 11 and the single axial support 21, the resonance of the cylindrical mounting portion 4 and the annular inner wall 15 is achieved. Does not happen. As described above, due to the sound absorbing effect and the resonance preventing effect, the sound wave generated in the main body casing 2 does not propagate to the sound collector main body 25.
[0030]
(Example 2)
FIG. 5 shows a second embodiment of a vibration isolator for a sound collector according to the present invention. As in the first embodiment, the cylindrical mounting portion 4 has a cylindrical inner peripheral surface 5 and the elastic support 7 is joined to the cylindrical mounting portion 4 in contact with the annular end surface 6 of the cylindrical mounting portion 4. It is. In the first embodiment, the sealing lid 15 is heat-sealed to the inner peripheral surface of the sound absorbing buffer bag 11, but in the second embodiment, the end face of the sealing lid 15 is butt-welded to the end surface of the sound absorbing buffer bag 11 (heat fusion). ) Has been. The sealing lid 15 according to the second embodiment is different from the sealing lid 15 according to the first embodiment in that the sealing lid 15 swells in a convex shape.
[0031]
(Other Examples)
The space between the inner peripheral surface of the cylindrical mounting portion 4 and the outer peripheral surface of the sound absorbing cushioning bag 11 can be heat-sealed during molding. The cross-sectional shape of the sound absorbing bag 11 is not limited to a concentric circle but may be an ellipse or a square. The sound absorbing bag 11 is not limited to a single continuous ring, and attenuates even if it is made of a plurality of divided cavities. The effect is similar.
[0032]
【The invention's effect】
According to the present invention, the following effects can be obtained. Due to the sound absorbing effect and the resonance preventing effect, the sound wave propagating through the external solid does not propagate to the sound collector, so that the sound collector does not pick up noise. Also, the manufacturing cost is low.
[Brief description of the drawings]
FIG. 1 is a sectional view showing Embodiment 1 of a vibration isolator of a sound collector according to the present invention.
FIG. 2 is a sectional view of a mold for an injection molding machine used in a first step of assembly.
FIG. 3 is a sectional view of a mold for an injection molding machine used in a second step of assembly.
FIG. 4 is a sectional view showing a third step of assembly.
FIG. 5 is a sectional view showing Embodiment 2 of the vibration isolator of the sound collector according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Vibration isolator main body 4 ... Cylindrical mounting part 5 ... Inner peripheral surface 7 ... Elastic support 11 ... Sound absorbing buffer bag 17 ... Vibration damping material 25 ... Sound collector main body 26 ... Outer peripheral surface

Claims (3)

A sound collector main body (25) having a sound collecting means having a sound collecting function therein is held at the center, and has a closed cavity surrounding the outer periphery of the sound collector main body (25) and is formed of a resin elastomer. An elastic cavity forming body (11);
A vibration damping liquid (17) sealed in the closed cavity of the elastic cavity forming body (11) for damping vibration;
A vibration isolator for a sound collector, comprising: a vibration isolator main body (1) holding the elastic cavity forming body (11) at a central portion and surrounding an outer peripheral portion of the elastic cavity forming body (11);
The elastic cavity forming body (11) is interposed between the elastic cavity forming body (11) and the sound collector body (25), and is integrally connected to an inner portion of the elastic cavity forming body (11). ) Comprising an axial support (21) for supporting the sound collector body (25) in the axial direction of the central axis surrounded by the sound collector. In claim 1,
The elastic cavity forming body (11) is formed in an annular shape so that the cavity is annular, and is formed so as to hold an outer peripheral surface (26) of the sound collector body (25). A vibration isolator for a sound collector, wherein an outer peripheral surface (22) of the elastic cavity forming body (11) is in contact with and joined to an inner peripheral surface (5) of (1). In claim 1,
The elastic cavity forming body (11) is formed in an annular shape so that the cavity is annular, the sound collector body (25) is formed to have an outer peripheral surface (26), and the vibration isolator body (11) is formed. The outer peripheral surface of the elastic cavity forming body (11) is inscribed in the inner peripheral surface (5) provided in 1), the axial support (21) is annular, and the outer peripheral surface of the axial support (21) is provided. Is in contact with the inner peripheral surface of the elastic cavity forming body (11).

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