JPS5817504B2 - Vibration isolating material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vibration isolating material, and provides a vibration isolating material which is particularly suitable for application to a vibration isolating device (insulator) for a record player.

Conventionally used vibration isolating materials are made of springs, sponges, felts, liquids, gases, rubber, etc.
Among these, those made of rubber are vulcanized rubber obtained by three-dimensionally crosslinking polymers, or those obtained by dissolving a plasticizer (for example, oil) that is compatible with the base polymer between the rubber molecules.

This anti-corrosion material is suitable for absorbing high-frequency vibrations because when vibrations are applied, internal friction between rubber molecules dampens the vibrations.

However, when considering rainproofing of acoustic products (particularly record players), the influence of external vibrations from the floor on which the player is placed is significant, and frequency analysis of this external imaging shows that the frequency is below 100 Hz (particularly 2 OHz). Therefore, we cannot expect much attenuation effect.

This is because only the internal friction between rubber molecules contributes to the absorption of imaging, and the plasticizer as the second component is dissolved in the first component, so the internal loss due to this OT plasticizer is reduced. This is probably because it is not widely available.

The present invention aims to correct the above-mentioned defects.
The present invention relates to a vibration isolating material comprising a mixture of the first component and the first component, wherein the first component is crosslinked.

By configuring in this way, it is possible to improve the vibration damping effect, and in particular, to improve the absorption efficiency of low frequency vibration components.

The first component according to one aspect of the present invention is a base polymer, which preferably forms a network crosslinked structure, and examples of the material include liquid polybutadiene, liquid silicone rubber, liquid chloroprene, and liquid polysulfide. Rubber, residue 2-
Examples include liquid polymers such as IJ rubber, liquid butyl, and liquid urethane.

Further, the second component according to the present invention has poor compatibility with the first component ζ, and is dispersed and contained in the crosslinked first component, and its materials include liquid polybutene, liquid polyisobutylene, etc. liquid polymers.

The present invention is made by mixing the above-mentioned first and second component materials with each other at a predetermined temperature, and adding a curing agent such as incyanate to cross-link between the first component and the second component. to gel.

As schematically shown in Figure 1, the structure of the anti-vibration gel thus obtained is such that the second component 2 is not dissolved in the first component 1 as the base polymer, but is dispersed and mixed therein. It is something.

Therefore, when the force is applied to the sensor, viscous flow (plastic flow) occurs in the second component 2 at the interface between the first component 1 and the second component 2, for example in the direction of the arrow, and this causes the internal The loss, together with the internal friction between the molecules of the first component 1, contributes to the vibration damping effect and increases the vibration absorption efficiency, especially at low frequencies.

That is, the vibration isolating material according to the present invention has the following features which are necessary conditions for a vibration isolating material.

(1) It has large damping characteristics (internal resistance).

(2) Extremely soft spring characteristics (elastic modulus) can be obtained.

(3) A large strain rate (displacement/thickness) can be obtained.

In addition, to define the above-mentioned compatibility here, when polymer A and polymer B to be mixed are poured into a test tube at a ratio of, for example, 1:1 (volume ratio) and mixed thoroughly, the cloudiness indicates that the polymer It is clear that A and B are not compatible.

Even if it does not become cloudy, for example, if the original polymers A and B separate when left for a day and night, the two polymers are judged to be incompatible; is said to be in good condition.

Next, the vibration isolating material according to the present invention will be explained in more detail with reference to examples.

Example 1 In this example, the following materials were used for the vibration isolating material.

Liquid polybutadiene (first component) 100 parts by weight (product name: Idemitsu Polybutadiene R-45M) Liquid polybutene (second component) 100 ll (product name: Idemitsu Polybutene 1)
00 R,) incyanate (curing agent) 10
(Chemical name: MDl 4.4'-diphenylmethane diisocyanate) In this case, the second component, liquid polybutene (plasticizer), is the first component, liquid polybutadiene (base polymer).
Because of its poor compatibility with the mixture, a high viscosity was used instead.

That is, when a second component with poor compatibility with the first component is used, so-called bleed occurs in which the second component oozes out onto the surface. However, since the second component according to this example has a high viscosity, We were able to effectively prevent such bleeding.

The above compounded materials were mixed with each other at room temperature, and the first component was crosslinked and cured in about 24 hours by the action of the isocyanate, which is a curing agent.

In this case, the incyanate group of the isocyanate (-NC
O) and the terminal hydroxyl group (-OH) of polybutadiene reacted, and the first component, polyphtadiene, became a three-dimensional network structure.

In the above-mentioned formulation example, the first component and the curing agent were mixed in equal amounts (i.e., NC010H-210), but when NC010H=0.
It may be varied within the range of 5 to 1.0.

If this ratio is less than 0.5, the amount of the first component will be too small and it will be difficult to maintain the shape of the net-like three-dimensional structure.
If it exceeds 0, the excess first component no longer contributes to the reaction and is wasted.

In addition, 10 to 10 parts by weight of the second component is added to 100 parts by weight of the first component.
Although it may be changed to 300 parts by weight, it is not desirable if it is outside this range.

That is, if the second component is less than 10 parts by weight, the internal loss due to the second component will be small and the vibration damping effect will be weak, and if it exceeds 300 parts by weight, the second component will be too large and the vibration damping material will not be able to maintain its shape. It becomes difficult to gel.

Next, an example in which the vibration isolating material obtained in this example is used in a record player will be described with reference to FIGS. 2 to 4.

Although not shown in FIG. 2, the vibration isolating device 3 is filled with a gelled vibration isolating material 5 according to this embodiment in a protective rubber cup 4, and the upper opening of the rubber cup 4 is formed by a metal or plastic plate 6.
The peripheries of the rubber cup 4 and the metal or plastic plate 6 are fixed together by a tightening ring 7.

Further, a mounting screw 8 is provided at the center of the upper surface of the metal or plastic plate 6.

In addition, as shown in FIG. 3, a structure may be adopted in which the vibration isolating material 5 is directly sandwiched between metal or plastic plates 6 from both sides.

As shown in FIG. 4, such a vibration isolator 3 is screwed and fixed to the four corners of the bottom surface of the main body 10 of the record player 9, and placed in a predetermined position in this state.

Therefore, external vibrations from the surface on which the player 9 is placed (for example, the floor) are absorbed by the vibration isolating material 5 of the vibration isolator 3 on the bottom of the player 9, and especially low frequency vibrations have a negative impact on the record stylus of the player. Therefore, howling can be effectively prevented.

In fact, when we measured the vibration frequency characteristic curve of this type of player against the external vibration Q, we obtained the results shown in FIG.

In this figure ζ, the curve a corresponds to the case where the vibration isolating material according to the present embodiment ζ is used, and the curve C corresponds to the case where the conventional vulcanized rubber is used as the vibration isolating material.

In the case of conventional vulcanized rubber, as mentioned above, the vibration loss due to the vulcanized rubber is small, so the resonance frequency f.

The gain becomes high, and at this time the Q value also becomes a dog.

This Q value is expressed as tan δ = 1/Q (δ is the loss angle), but when the Q value is large, the vibration transmission characteristic shows an ideal characteristic of -12 dB/oct, but at the resonant frequency fo The peak of the gain becomes high, and as a result, the vibration damping characteristics become extremely poor, and the vibrating string continues to vibrate.

On the other hand, if the Q value is too small, the gain peak at the resonant frequency fo will be low and vibration attenuation will be fast, but on the other hand, the vibration transmission characteristics will deteriorate, making it less effective as a vibration isolator. become scarce.

However, the vibration isolating material according to this embodiment has a large vibration loss, so the gain is low.

That is, as shown by the curve a, the gain peak at the resonant frequency fo is not high, the vibration transmission characteristics are not bad, and the damping effect is sufficient, indicating a good Q value.

Example 2 In this example, the following materials were used for the vibration damping material.

Liquid polybutadiene (first component) 100 parts by weight (same as Example 1) Liquid polybutene (second component) 200 l/(trade name: Idemitsu Polybutene 100 R or 35R) Aroma Oihabe third component) 50 l/(trade name) :Diana Brothess Oil AH-10) Incyanate 10 (same as Example 1) In this case, the amount of liquid polybutene, which is the second component, was increased compared to Example 1. However, in order to prevent this, allofoil is mixed as a third component with good compatibility with both the first component and the second component, which are base polymers (7).

Therefore, in the vibration isolating device for a record player using the vibration isolating material according to this embodiment, the compatibility is determined to some extent by the third component, so that the frequency characteristics of the vibration transmissibility as shown in the curve in FIG. 5 can be obtained. and the resonant frequency f.

It can be seen that the gain peak at is higher than that of curve a (Example 1).

However, it shows that the damping characteristics are better than curve C (conventional vulcanized rubber), and the vibration transmission characteristics are not bad.

Example 3 In this example, sludge was used as a compounding material for the vibration damping material, and the vibration damping effect was good.

Liquid silicone rubber (first component) 100 parts by weight (product name: Shin-Etsu Silicone RTVKE 104 gel) Liquid polyisobutylene (second component) 100 (product name: ES So Vistanex) Chloroplatinic acid (curing agent) 10 In this case The amount of liquid polyisobutylene (plasticizer), which is the second component, may be varied within the range of 10 to 150 parts by weight, but if it is out of this range, the vibration damping effect will be poor or it will gel and become stiff.

Example 4 In this example, the following materials were used as the compounding materials for the vibration damping material, and the vibration damping effect was still good.

Liquid chloroprene (first component) 100 parts by weight (trade name: DENKA-LCR) Liquid polybutene (second component) 100# (same as Example 2) Aliphatic polyamine (curing agent) 10 l・In this case, second component The amount of liquid polybutene (plasticizer) as a component is 10
It may be varied within the range of ~400 parts by weight, but if it is out of this range, the vibration damping effect will deteriorate or it will gel.
It gets rich.

Hereinafter, the present invention has been explained with reference to examples, but in addition to the components listed in the examples above, the following crosslinkable liquid polymers were used as a base polymer, and the following plasticizers were used as a base polymer (in contrast, compatible Can be used as a bad polymer.

That is, as a base polymer, liquid polysulfide rubber (Th1okol Lp Type manufactured by Thioelle Chemical Company, USA) is used.
e) Liquid nitrile rubber (Nirapol 131 manufactured by Nippon Zeon Co., Ltd.)
2) Liquid butyl (Etsobutyl HT45 manufactured by Esso Corporation) and liquid urethane (Eronate casting elastomer manufactured by Nippon Polyurethane Co., Ltd.) are considered, and as plasticizers, liquid polymers such as various oils (paraffin type) and epoxy type are also considered. .

The vibration isolating material according to the present invention can be used to prevent floor vibrations (Q) from electric refrigerators, floor vibrations caused by speaker cabinet vibrations (
It can be applied to prevent vibrations when installing a video device on a transport vehicle, etc.

As described above, the present invention mixes a first component made of a liquid polymer and a second component made of a liquid polymer that has poor compatibility with the first component, and crosslinks the first bean component containing the second component. Therefore, not only the internal friction between molecules but also the internal loss (viscous flow) at the interface between the first component and the second component can be used, which improves the vibration damping effect and has good vibration transmission characteristics. Therefore, the optimum Q value can be selected, and the absorption efficiency of low frequency vibration components can be particularly improved.

[Brief explanation of the drawing]

The drawings are for explaining the vibration isolating material according to the present invention, and FIG. 1 is a schematic sectional view of the vibration isolating material showing a mixed state of the first component and the second component, and FIG. 3 is a sectional view of another example of a vibration isolator, and FIG. 4 is a perspective view of a record player equipped with the vibration isolator shown in FIG. 2. , FIG. 5 is a comparative curve diagram showing frequency characteristics of vibration transmissibility. In the reference numeral Q used in the drawings, 1 is the first component, 2 is the second component, 3 is the vibration isolator, and 5 is the vibration isolator.

Claims (1)

[Claims] 1. Consisting of a mixture of a first component made of a liquid polymer and a second component made of a liquid polymer and having poor compatibility with the first component, the first component is crosslinked. Anti-vibration material.