JP2824922B2 - Vibration absorbing member - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to vibration absorption that can be used in various shapes for various instruments and devices that require vibration isolation, such as precision measuring instruments, audio equipment, vibration isolation tables, and vehicle bodies. It relates to members.

[Related Art] Conventionally, various rubbers represented by butyl rubber are most often used as vibration absorbing members. High-performance materials such as oil-extended rubber and urethane-based shock-absorbing polymers are also known. However, these materials have natural frequencies of several tens to several hundred Hz. Therefore, the range in which the performance can be exhibited is limited to the high frequency range.

Also, recently, a material in which a gel is sealed in a soft solid viscoelastic material has been attracting attention as a high-performance vibration damping material. However, this is not a high-performance material although the natural frequency is low but the vibration transmissibility is not necessarily smaller than that of a solid.

Further, an oil damper is known as a liquid material. However, this was incorporated into a complex system as represented by an engine mount, and its shape was characterized by a lack of versatility.

[Problems to be Solved by the Invention] An object of the present invention is to provide a material having a low natural frequency and a small vibration transmissivity at the time, and having excellent vibration absorption.

[Means for Solving the Problems] In view of the above situation, the present inventors have conducted intensive studies, and as a result, completed the present invention.

That is, the present invention has an elastic modulus of 10 ² to 10 ⁵ dyne / cm ² ,
A composition obtained by adding a flake-like filler to a viscoelastic liquid of 10 poise or more has an elastic modulus of 10 ⁶ to 10 ¹⁰ dyne / cm ² and a loss factor of
The present invention relates to a vibration-absorbing member that is sealed in an exterior material made of a solid viscoelastic material of 0.15 or more.

 The details will be described below.

FIG. 1 is a schematic view showing a cross section of the vibration absorbing member of the present invention. A composition comprising a viscoelastic liquid 1 and a flake-like filler 2 is enclosed in an exterior material 3.

The viscoelastic liquid used in the present invention has an elastic modulus of 10 ² to 10 ⁵ dy.
ne / cm ² , viscosity is 10poise or more. The elastic modulus shown here is a value obtained by measuring at a temperature of 25 ° C. and a frequency of 1 Hz with a viscoelasticity measuring device represented by a Weisenberg Gregoniometer. Elastic modulus is less than 10 ² dyne / cm ² , viscosity is 1
In the case of a viscoelastic liquid of less than 0 poise, the vibration transmissibility at the natural frequency increases, and it is difficult to say that the vibration absorption is excellent.
Further, when the elastic modulus exceeds 10 ⁵ dyne / cm ² , the natural frequency increases, and it is difficult to say that this also has excellent vibration absorption.
Viscoelastic liquid used in the present invention is its elasticity modulus 10 ³ to 10 ⁴ dyne
/ cm ² and a viscosity of 10 ² to 10 ⁴ poise are preferred. Examples thereof include a polymer liquid such as silicone oil, polyethylene glycol and polybutadiene, a polymer viscous solution such as a decalin solution of a styrene-butadiene-styrene copolymer, a plasticizer, glycerin, and liquid paraffin.

The filler used in the present invention is in the form of flakes. The present inventors have studied with the idea that by adding a filler into a viscoelastic liquid, it is possible to express some interaction between the filler and the liquid or between the fillers to improve the performance. However, it has been found that the flake-like filler has the highest performance. Moreover, the effect is not uniform depending on the type and size of the flakes. Examples of the flake-like filler include mica, talc, glass, graphite, and wood chips, and glass or mica can exhibit preferable vibration damping performance. Further, the particle size of the flakes is preferably 40 μ or more. It is more preferable to use flakes of 70 μm or more. This filler can be mixed with the viscoelastic liquid in any ratio, but it is most effective to impregnate the filler with the viscoelastic liquid to make the liquid hard to flow. Filler particle size,
Although it cannot be said unconditionally depending on the thickness etc., for example, viscosity of 1000 po
For glass flakes containing ise silicone oil and 80% or more flakes of 200μ or more, 10: 1 to 2: 1 by weight
The effect of adding the filler can be exhibited by the degree. This idea was not found in the conventional anti-vibration material. These flake-like fillers may be surface-treated with a silane coupling agent or the like, and fillers of other shapes can be added as long as the performance is not deteriorated.

The exterior material 3 used in the present invention has an elastic modulus of 10 ⁶ to 10 ¹⁰ d.
It is necessary that yne / cm ² and the loss coefficient have values of 0.15 or more. The elastic modulus and loss coefficient shown here are measured at an ambient temperature of 25 using a dynamic viscoelasticity measuring device represented by Leo Vibron.
It is a value obtained by measuring at ° C and a frequency of 10 Hz. Elastic modulus
In the case of a solid viscoelastic substance of less than 106 dyne / cm ² , it is difficult to hold the vibrated body in a stable state because it is very soft even when the liquid composition is sealed. The elastic modulus is 10 ¹⁰ dy
If it exceeds ne / cm ² , even if the liquid composition is enclosed, the liquid composition is very hard, and the performance of the liquid composition is not exhibited, and the natural frequency increases. Furthermore, the elastic modulus is 8 × 10 ⁶ to 2 × 10 ⁷
Dyne / cm ² is more preferred. 2 × 10 ⁷ -10 ¹⁰ dyne / cm
^In case ( ² ), a high-performance vibration-absorbing material can be produced by changing the shape such as the thickness and length of the exterior material. Further, it is preferable that the loss coefficient has a large value. For example, rubbers such as butyl rubber and silicone rubber, plastics such as polyvinyl chloride and ethylene-vinyl acetate copolymer, and compositions and mixtures thereof can be used.
Further, the shape of the exterior material is not particularly limited, and those formed into any shape according to the purpose can be used. As the molding method, hot press, injection molding, air pressure molding and the like can be considered, but it is not particularly limited.

The vibration absorbing member of the present invention is obtained by enclosing a composition comprising a viscoelastic liquid and a flake-like filler in an exterior material. As the encapsulation method, pressure bonding of the exterior material with an adhesive, fusion by heat, and the like can be considered, but are not particularly limited. In addition, there is no problem even if an inorganic additive or a flame retardant, which is usually used, is added to the exterior material. Further, for the purpose of enhancing the stability as a member, a metal plate or a wood plate may be bonded or embedded in the exterior material in parallel with a surface in contact with the vibrating body and the non-vibrating body. An example at this time is shown in FIG.

EXAMPLES Hereinafter, the present invention will be described with reference to Examples, but the present invention is not limited to these Examples.

Example 1 As shown in FIG. ² , a silicone rubber having an elastic modulus of 1.5 × 10 ⁷ dyne / cm ² and a loss coefficient of 0.18 was used. In addition, an elastic material of 6 × 10 ³ dyne / cm ² and a viscosity of 100
Enclose a composition in which 0poise silicone oil and glass flakes with an average particle size of 200μ are mixed at a weight ratio of 4: 1,
A vibration absorbing member was obtained.

Examples 2 to 4 Instead of the silicone oil used in Example 1, a silicone oil having an elastic modulus of 6 × 10 ² dyne / cm ² and a viscosity of 100 poise, an elastic modulus of 2 × 10 ⁴ dyne / cm ² and a viscosity of 3000 poise were used. Silicone oil, elasticity 2.5 × 10 ³ dyne / cm ² , viscosity 400poi
A vibration absorbing member was obtained by using each of the liquid polybutadienes of se.

Comparative Example 1 A vibration absorbing member was obtained using water (viscosity 0.01 poise) instead of the silicone oil used in Example 1.

Comparative Example 2 A vibration absorbing member was obtained by using a silicone oil having an elastic modulus of 60 dyne / cm ² and a viscosity of 9.7 poise instead of the silicone oil used in Example 1.

Comparative Example 3 The silicone oil of Example 1 was sealed in the silicone rubber exterior material of Example 1 to obtain a vibration absorbing member.

Example 5 A vibration absorbing member was obtained by using a talc having an average particle size of 47 μ instead of the glass flake used in Example 1.

Example 6 A vibration absorbing member was obtained by using mica having an average particle size of 1000 μm instead of the glass flake used in Example 1.

Example 7 A vibration absorbing member was obtained by using glass flakes having an average particle size of 35 μ instead of the glass flakes used in Example 1.

Example 8 Among the vibration absorbing members of Example 6, a vibration absorbing member was obtained by using a composition obtained by mixing silicon oil and mica at a weight ratio of 2: 1.

Comparative Example 4 Fiber diameter instead of glass flake used in Example 1
A vibration absorbing member was obtained using a glass strand having a size of 13 μ and an average fiber length of 35 μ.

Comparative Example 5 Fiber length instead of glass flake used in Example 1
A vibration absorbing member was obtained using a 1.5 mm glass chopped strand.

Comparative Example 6 A vibration absorbing member was obtained using glass beads having a central particle size of 18 μ instead of the glass flakes used in Example 1.

Comparative Example 7 A vibration absorbing member was obtained by using calcined kaolin clay (clay mineral) having a center particle size of 1.5 μ instead of the glass flake used in Example 1.

Example 9 Instead of the silicone rubber used in Example 1, the elastic modulus was 1.
A vibration-absorbing member was obtained using an exterior material made of polybutadiene rubber having 7 × 10 ⁷ dyne / cm ² and a loss factor of 0.24.

Comparative Example 8 Instead of the silicone rubber used in Example 1, an elastic modulus of 8 was used.
A vibration-absorbing member was obtained using an exterior material made of silicone gel having × 10 ⁵ dyne / cm ² and a loss factor of 0.38.

Example 10 Instead of the silicone rubber used in Example 1, the elastic modulus was 1.
Using polyvinyl chloride with 6 × 10 ⁸ dyne / cm ² and a loss factor of 0.7, the thickness of the side surface in contact with the liquid composition is 1 mm
A vibration absorbing member was obtained using the exterior material prepared as described above.

Comparative Example 9 Instead of the silicone rubber used in Example 1, the elastic modulus was 2.
A vibration-absorbing member was obtained using an exterior material made of polybutadiene rubber having 3 × 10 ⁷ dyne / cm ² and a loss coefficient of 0.12.

Measurement of Vibration Isolation Performance of Vibration Absorbing Member The vibration absorbing members obtained in Examples 1 to 10 and Comparative Examples 1 to 9 were subjected to a vibration test device (MSE-450, manufactured by Akashi Seisakusho Co., Ltd.).
The weight dispersion of 1 kg was placed on the vibration absorbing member, and the frequency dispersion of the vibration transmissibility between the base and the weight was examined. Table 1 shows the natural frequency and vibration transmissibility of the system at that time.

[Effects of the Invention] As is clear from the above description, according to the present invention, a material having a low natural frequency, a small vibration transmissivity at that time, and excellent vibration absorption can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a cross section of the vibration absorbing member of the present invention. FIG. 2 is a schematic view showing a cross section in which a metal plate is mounted on a surface of the vibration absorbing member of the present invention in contact with a vibrating body and a vibrated body. 1: Viscoelastic liquid 2: Flaky filler 3: Exterior material 4: Metal plate

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI F16F 15/08 F16F 13/00 620A

Claims (1)

(57) [Claims] An elastic modulus of 10 ² to 10 ⁵ dyne / cm ² and a viscosity of 10 poise
Vibration obtained by encapsulating a composition comprising the above viscoelastic liquid and a flake-form filler in a solid material made of a solid viscoelastic substance with an elastic modulus of 10 ⁶ to 10 ¹⁰ dyne / cm ² and a loss coefficient of 0.15 or more Absorbing member.