JP2000213595A - Vibration isolating member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To adjust a spring constant and a loss coefficient which are vibration isolating factors, in a wide range by filling granular material in a container to form a vibration isolating member. SOLUTION: This vibration isolating member 5 used to support the flexible structure of a vibrating body 6 of a structure or equipment is constituted by filling granular material 2... such as glass beads in a container 1. In order to support the vibrating body 6 of 1 kg in mass in the vibration isolating state, a large number of granular material 2 with the grain diameter ϕ 125 μm are filled in the cylindrical container 1 with the inner diameter ϕ 50 m. A side wall part 3 of the container 1 of the vibration isolating member 5 is smaller in rigidity than the granular material 2 so that the side wall part 3 of the container 1 swells outward when receiving vibration, thus avoiding the granular material 2 being influenced by the rigidity of the side wall part 3. If necessary, viscoelastic material grain 4 formed of rubber material can be mixed in the powder and grain material 2. Frictional contact damping between the grains of the granular material 2 is therefore increased to adjust loss in a wide range.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-vibration member,
For details, do not transmit vibration generated from various structures and equipment to the floor and other parts, or prevent vibration and vibration insulation from transmitting vibration of the vibrating floor to structures and equipment. The present invention relates to a vibration isolating member having performance.

[0002]

2. Description of the Related Art Vibration prevention will be described with reference to vibration transmission characteristics shown in FIG. In FIG. 9, the horizontal axis represents frequency, and the vertical axis represents the vibration transmission magnification representing how many times the vibration of the vibrating body is transmitted to other parts. The curves (A) and (B) in FIG.
FIG. 11 shows vibration transmission characteristics when a flexible structure supporting portion 5 ′ having a spring constant k and a loss coefficient η is provided on a vibrating body 6 such as a structure or a device having a mass m as shown in FIG. 10. Here, the curve (A) in FIG. 9 shows that the loss coefficient η of the support 5 ′ is very small.
The curve (B) shows the vibration transmission characteristics when the loss coefficient η is large, and f ₀ in the figure represents the resonance frequency determined by the mass m of the vibrating body 6 and the spring constant k of the support 5 ′. The amplitude amplification region M (a region where the vibration is amplified by a factor of 1 or more) is approximately 1.4 times or less of the resonance frequency f ₀ , and the vibration isolation region N is a region where the vibration is reduced by a factor of 1 or less. Area). As a characteristic of the vibration transmission characteristic, when the loss of the support portion 5 'is increased, the vibration transmission is reduced in the amplitude amplification region M, but is increased in the vibration isolation region N.

Here, as shown in FIG. 10, as a vibration isolating member used to support the flexible structure of the vibrating body 6, a rubber material a, a metal spring b, and the like shown in FIG.
Alternatively, an air spring c or the like is used.

[0004] The basic idea of the vibration isolation design is to shift the peak of the resonance frequency f ₀ due to the vibration isolation support to the lower frequency side as much as possible so that the vibration frequency of the vibrating body falls within the frequency band of the vibration isolation region N. Next, the spring constant of the flexible structure is designed.

However, there are cases where it is impossible to shift the resonance peak to a lower frequency side due to vibration-proof support due to restrictions on the rigidity of the support portion. At this time, the support portion 5 '
Is designed so that the loss of the resonance peak is as large as possible and the height of the resonance peak in the amplitude amplification region M is kept low.

Further, there are many cases where the frequency component of the vibrating body as the excitation source is random vibration having various components from a low frequency band including the vibration amplification region M, or a case where an impact external force acts. In this case, in each of the vibration-proof region N and the vibration-amplifying region M, an optimal design of the spring constant k and the loss coefficient η of the support portion 5 ′ according to the frequency component of the vibration source must be performed.

As described above, in an actual anti-vibration design, a member must be designed according to an object to be anti-vibration such as a vibration frequency. However, in the conventional anti-vibration structure, it is not easy to adjust the spring constant k and the loss coefficient η, which are the anti-vibration design factors, and the adjustment range is narrow. Therefore, the conventional anti-vibration design includes different materials, manufacture of the support portion 5 'of various shapes,
Preparation was needed.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to make it possible to adjust a spring constant and a loss coefficient which are design factors for vibration isolation in a wide range. The object is to provide a vibration isolating member.

[0009]

In order to solve the above-mentioned problems, the present invention is characterized in that a granular material 2 is sealed in a container 1 of an anti-vibration member 5, and is configured as described above. Thus, the values of the spring constant and the loss coefficient of the vibration isolating member 5 are determined by the physical property conditions of the granular material sealed in the container 1 of the vibration isolating member 5 and the like. For example, by changing the particle stiffness, particle size, particle surface friction, sealing amount, etc. of the granular material 2, it is possible to adjust the spring constant and the loss coefficient, which are important design factors of the vibration isolation design, over a wide range. .

It is preferable that the rigidity of the side wall 3 of the container 1 is smaller than the rigidity of the granular material 2.
The vibration damping member 5 made of the powder material 2 is not affected by the rigidity of the
The adjustment of the spring and the loss becomes wider.

The viscoelastic material particles 4 are added to the granular material 2.
It is preferable to mix the viscoelastic material particles 4 to increase the frictional contact attenuation between the particles of the granular material 2. The value of the loss can be adjusted over a wide range.

It is preferable that the viscoelastic material particles 4 to be mixed are rubber-based materials. With such a configuration, a small amount of high-viscosity rubber-based particles is mixed to reduce the loss of the vibration isolator 5. The value can be adjusted over a wider range.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a vibration isolating member 5 according to the present invention will be described.
A typical embodiment will be described.

As shown in FIG. 1, the vibration damping member 5 of the present embodiment is configured by enclosing a granular material 2 in a container 1. The vibration isolating member 5 is used for supporting a flexible structure of the vibrating body 6 such as various structures and devices. Vibration generated from the vibrating body 6 is not transmitted to other floors 7 and the like. Anti-vibration so that vibration of the vibrating floor 7 and the like is not transmitted to the vibrating body 6;
Has vibration isolation performance. In this example, a large number of glass beads 2a having a particle diameter of 125 μm are sealed in a cylindrical container 1 having an inner diameter of 50 m so that the vibrating body 6 having a mass of 1 kg can be supported by vibration isolation.

FIG. 2 shows the difference in the height of the glass beads 2a.
The figure shows a vibration transmission characteristic in the case where the vibration is applied. Curve (C)
Is the filling height L₁Is 30 mm, and curve (D) is the encapsulation height L.
_Two(> L ₁) Is 50 mm. This
As can be seen from FIG. 2 of FIG.
Then, the resonance frequency f₀Is low
You. That is, the spring constant of the anti-vibration support can be reduced.

FIG. 3 shows a curve (E) when the glass beads 2a having a particle diameter of 125 μm are sealed up to a height of 50 mm under the same conditions as those of the vibrator 6 and the container 1, and a curve (F) shows a nitrile having a particle diameter of 125 μm. Rubber beads 2b are 50m high
The vibration transmission characteristics when sealing up to m is shown. As can be seen from FIG. 3, by changing the granular material 2 from the glass beads 2a to the nitrile rubber beads 2b, the resonance frequency f ₀ due to the vibration-proof support can be largely shifted to a lower frequency range, and the height of the resonance peak is also reduced. Due to the increased loss, it can be kept low.

As described above, in the same container shape in which the granular material 2 is enclosed, only the type (glass, nitrile rubber, etc.) and the amount of the granular material 2 to be enclosed are design factors of the vibration-proof support. Spring, loss can be changed and adjusted. Therefore, when designing the vibration isolating member 5 according to the object of the vibration isolation such as the vibration frequency, the vibration source N in each of the vibration isolation region N (FIG. 9) and the vibration amplification region M (FIG. It is not necessary to design the spring constant k and the loss coefficient η of the vibration isolating member 5 in accordance with the frequency components of
It is possible to adjust the spring constant k and the loss coefficient η, which are design factors for vibration isolation, in a wide range.

Further, even when the particle stiffness, particle size, particle surface friction, etc. are changed in addition to the type and amount of the granular material 2, the spring and loss, which are design factors of the vibration isolation support, are changed.
Can be adjusted. An example will be described below.

FIG. 4 shows a case where the rigidity of the side wall 3 of the container 1 of the vibration isolating member 5 is smaller than the rigidity of the granular material 2. When vibration is applied, the powders in the container 1 come into contact with each other to cause energy attenuation, and the vibration energy is absorbed. At this time, since the rigidity of the side wall portion 3 of the container 1 is smaller than the rigidity of the granular material 2, the side wall portion 3 of the container 1 expands outward when subjected to vibration as shown in FIG. As a result, the granular material 2 is not affected by the rigidity of the side wall 3 of the container 1, and the adjustment of the spring and the loss of the vibration isolating member 5 by the granular material 2 becomes wider.

FIG. 5 shows a case where the viscoelastic material particles 4 are mixed in the granular material 2 sealed in the vibration isolating member 5. The mixing of the viscoelastic material particles 4 increases the frictional contact attenuation between the particles of the granular material 2, and the loss can be adjusted over a wide range depending on the mixing amount.

Here, the mixed viscoelastic material particles 4
Is preferably a rubber-based material. This rubber-based material is a low-elastic material and has a viscosity (hysteresis property) due to elastic deformation, and isoprene rubber (IR), styrene-butadiene rubber (SBR), butadiene rubber (BR), ethylene-propylene rubber (EPM, EPDM), butyl rubber (IIR), chloroprene rubber (CR), nitrile rubber (NBR), acrylic rubber (ACM), epichlorohydrin rubber (CO, ECO), chlorinated polyethylene (CM), chlorosulfonated polyethylene (CSM) ) And the like. Natural rubber (N
R), and recycled rubber for recycling. As described above, the limitation on the rubber-based material makes it possible to increase the loss for adjusting the loss of the vibration isolating member 5 by mixing a small amount of highly viscous rubber-based particles.

The curve (G) in FIG. 6 shows that glass beads having a particle diameter of 125 μm are placed in a cylindrical container 1 having an inner diameter of 50 mm and a height of 40 μm.
mm is shown, and the vibration transmission magnification to the floor when a 1 kg vibrator is placed thereon is shown. Curves (H), (I), and (J) in FIG. 6 show the case where nitrile rubber beads (viscoelastic material particles) having a particle diameter of 50 μm are mixed into glass beads (powder material). Curve (H) shows a mass ratio of nitrile rubber beads of 5%, (I) shows 10%,
(J) shows the case of 20%. According proportion of incorporation of the nitrile rubber beads as can be seen from FIG. 6 is increased, have reduced peak height of the frequency f ₀ of the resonance, it can be confirmed that the attenuation has increased greatly. It can be seen that by adjusting the amount of the viscoelastic material particles 4 mixed, the loss value of the vibration isolating member of the present invention can be adjusted over a wide range.

Hereinafter, typical embodiments of the vibration isolating member according to the present invention will be described. (Example) An anti-vibration member has an inner diameter of 50 mm and a side wall thickness of 0.1 mm.
A 5 mm rubber material cylindrical container is filled with glass beads having a particle diameter of 125 μm to a height of 40 mm.
The nitrile rubber beads of μm are mixed so that the mass ratio with the glass beads becomes 10%. Then, as shown in FIG. 7, the vibration isolating member 5 is adhered to a healthy home appliance 51. FIG. 7 shows a case where four vibration damping members 5 of the present invention are installed on a support portion of a certain healthy home appliance 51, and the vibration of the installation floor 60 is measured by a vibration acceleration sensor 53 shown in the figure. FIG. 8 is a graph of measurement results showing the reduction of the vibration acceleration level according to the embodiment of the present invention. The curve (A) shows the case without the vibration isolating member, and the curve (B) shows the outer diameter φ50.
In the case of using a vibration-isolating butyl rubber having a height of 40 mm and a height of 40 mm, the curve (C) shows the respective vibration accelerations of 1/3 octave band in the case of using the spring of the member and the vibration-insulating member of the present invention whose loss has been adjusted. The level comparison result is shown. As shown by the curve (C), it can be confirmed that the anti-vibration member of the present invention has high anti-vibration performance.

[0024]

As described above, according to the first aspect of the present invention, since the granular material is sealed in the container of the vibration isolating member, the values of the spring constant and the loss coefficient of the vibration isolating member are reduced. Is determined by physical property conditions of the granular material sealed in the container of the vibration isolation member. For example, by changing the particle stiffness, particle size, particle surface friction, sealing amount, etc. of the granular material 2, when designing a vibration isolating member according to a vibration isolating object such as a vibration frequency, a vibration isolating design factor The spring constant and the loss coefficient can be adjusted over a wide range.

According to the second aspect of the present invention, in addition to the effect of the first aspect, the rigidity of the side wall portion of the container is made smaller than the rigidity of the granular material, so that the granular material is formed on the side wall of the container. The adjustment of the spring and the loss of the vibration isolating member by the granular material becomes wider without being affected by the rigidity of the portion.

According to a third aspect of the present invention, in addition to the effect of the first or second aspect, since the viscoelastic material particles are mixed in the granular material, the powder is mixed with the viscoelastic material particles. The frictional contact attenuation between the particles of the granular material increases, and the value of the loss of the vibration damping member can be adjusted over a wide range depending on the amount of the mixing.

According to a fourth aspect of the present invention, in addition to the effect of the third aspect, since the viscoelastic material particles to be mixed are rubber-based materials, a small amount of highly viscous rubber-based particles can be prevented from being mixed. The value of the loss of the vibration member can be adjusted over a wider range.

[Brief description of the drawings]

FIGS. 1A and 1B show an example of an embodiment of the present invention, in which FIG. 1A is an explanatory view showing a case where a vibration isolating member of the present invention is installed on a supporting portion of a vibrating body such as a structure or a device, and FIG. It is a conceptual diagram of a member.

FIG. 2 is a graph showing a change in vibration transmission characteristics due to a difference in the amount of a granular material filled in the vibration isolating member.

FIG. 3 is a graph showing a change in a vibration transmission characteristic due to a difference in the granular material according to the first embodiment.

FIGS. 4A and 4B show another embodiment, wherein FIGS. 4A and 4B are explanatory views of a case where the vibration isolating member of the present invention is installed on a supporting portion of a vibrating body such as a structure or a device, and FIG. It is a conceptual diagram when vibration is applied to a member.

5A and 5B show still another embodiment, in which FIG. 5A is an explanatory view showing a case where the vibration damping member of the present invention is installed on a supporting portion of a vibrating body such as a structure or a device, and FIG. FIG. 4 is a conceptual diagram when viscoelastic material particles are mixed into the slab.

FIG. 6 is a graph showing a change in vibration transmission characteristics due to a difference in the amount of viscoelastic material particles mixed into the above granular material.

FIG. 7 is an explanatory diagram relating to measurement for confirming a vibration isolating effect of the healthy home appliance according to the present invention.

FIG. 8 is a graph of measurement results showing a reduction in vibration acceleration level according to an embodiment of the present invention.

FIG. 9 is a graph illustrating the principle of image stabilization.

10A is a conceptual diagram illustrating transmission of vibration from a vibrating body to a floor, and FIG. 10B is a conceptual diagram illustrating transmission of vibration from a floor to a vibrating body.

11A and 11B are explanatory diagrams of a conventional vibration isolating member, wherein FIG. 11A shows a case of a rubber material, FIG. 11B shows a case of a metal spring, and FIG. 11C shows a case of an air spring.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container 2 Granular material 3 Side wall part 4 Viscoelastic material particle 5 Vibration isolation member

Claims (4)

[Claims] An anti-vibration member characterized in that a granular material is sealed in a container. 2. The vibration damping member according to claim 1, wherein the rigidity of the side wall of the container is smaller than the rigidity of the granular material. 3. The vibration damping member according to claim 1, wherein viscoelastic material particles are mixed in the granular material. 4. The vibration damping member according to claim 3, wherein the viscoelastic material particles to be mixed are rubber materials.