JP2004218831A - Viscous liquid-filled damper and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a viscous liquid-filled damper and its manufacturing method, capable of improving durability and vibration controllability, especially under a high-temperature condition by preventing volume expansion under a high-temperature condition. <P>SOLUTION: In this viscous liquid-filled damper 1 composed of a container body 4 and a lid 5 and having the damper body which is formed by jointing both of them by means of ultrasonic welding or bonding and filled with a viscous fluid 6, an equilibrium moisture content of the viscous fluid 6 is set at ≤0.2%. This manufacturing method for the damper includes a process for setting the equilibrium moisture content of the viscous fluid 6 at ≤0.2%, and a process for filling the damper body with the viscous fluid 6. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a viscous liquid-filled damper in which a viscous liquid is filled inside a damper body, and is used between a support and a supported object to absorb vibration and to dampen the supported object. The present invention relates to a viscous liquid-enclosed damper and a method for manufacturing the same.

  The viscous liquid-filled damper is mounted between electronic devices such as a computer, a CD player, and an MD player built in the vehicle, for example, and absorbs vibrations caused by the engine and running of the vehicle, so that the vibrations are directly transmitted to the electronic devices. It makes it hard to get through. The viscous liquid sealing damper encloses a fluid having a specific viscosity such as silicone oil in a sealed container, and absorbs the vibration based on the viscous flow of the viscous liquid. The sealed container of the viscous liquid-enclosed damper is usually manufactured separately from the container main body and the lid, and the viscous liquid is put into the container main body. It is formed by welding or the like. Further, generally, the container body is a molded body of a soft resin such as an elastomer or a rubber elastic body, or a two-color molded body of a soft resin and a hard resin, while the lid is a molded body of a hard resin. . Further, the container body is provided with a shaft insertion portion for fitting the shaft at the time of attachment. In some cases, the container body and the lid are made of a rubber elastic body and both are vulcanized and bonded. Such a liquid-filled damper is described in, for example, Patent Document 1, and a liquid particle damper in which solid particles or a powder material is dispersed in a viscous fluid in order to improve damping characteristics has been developed (Patent Document 2). , 3).

  In such a liquid-filled damper, durability is required because the shaft inserted into the shaft insertion portion is always vibrated and a load is applied.

  However, when a liquid-filled damper is mounted on an automobile together with electronic equipment, the temperature inside the vehicle will reach 80 ° C. or higher in summer, so the load will increase due to the volume expansion of the damper, or the damping performance will deteriorate and the durability will decrease. The problem of the decrease in the number has occurred.

  Therefore, measures such as manufacturing the container body using a soft resin with good heat resistance, degassing the viscous liquid, and further increasing the filling rate of the viscous liquid to prevent expansion of the air layer are taken. Has been taken. It has also been studied to completely remove the air layer using a gas-permeable soft resin.

  However, there is a problem that the problem due to volume expansion is not completely improved.

JP-A-8-184345 (FIG. 1) Japanese Patent Application Laid-Open No. 2001-50344 (Claims, etc.) JP-A-2002-242977 (Claims, etc.)

  In view of such circumstances, an object of the present invention is to provide a viscous liquid-enclosed damper that prevents volume expansion under high-temperature conditions, and in particular, has improved durability and vibration damping properties under high-temperature conditions, and a method for manufacturing the same. I do.

  As a result of intensive studies to solve the above problems, the inventors found that the cause of the volume expansion of the damper was not the air in the damper container, but the water vapor contained in the viscous liquid, which was vaporized water vapor. Completed.

  According to a first aspect of the present invention, in a viscous liquid-enclosed damper in which a viscous liquid is enclosed in a damper body, an equilibrium water content of the viscous liquid is 0.2% or less. In the damper.

  According to a second aspect of the present invention, there is provided the viscous liquid-filled damper according to the first aspect, wherein an equilibrium water content of the viscous liquid is 0.1% or less.

  A third aspect of the present invention is the viscous liquid according to the first or second aspect, wherein the damper main body comprises a container main body and a lid, and both are joined by ultrasonic welding or adhesion. In the enclosed damper.

  A fourth aspect of the present invention is the viscous liquid-filled damper according to any one of the first to third aspects, wherein the viscous liquid is silicone oil.

  A fifth aspect of the present invention is the viscous liquid-filled damper according to any one of the first to fourth aspects, wherein the viscous liquid is sealed after being dehydrated under reduced pressure.

  According to a sixth aspect of the present invention, there is provided a method of manufacturing a viscous liquid-enclosed damper in which a viscous liquid is enclosed in a damper body, wherein a step of setting an equilibrium water content of the viscous liquid to 0.2% or less, Filling the damper body with a viscous liquid-filled damper.

  A seventh aspect of the present invention is the method for producing a viscous liquid-filled damper according to the sixth aspect, wherein an equilibrium water content of the viscous liquid is set to 0.1% or less.

  An eighth aspect of the present invention is the method for producing a viscous liquid-enclosed damper according to the sixth or seventh aspect, wherein the equilibrium moisture content of the viscous liquid is reduced by dehydration under reduced pressure.

  In the viscous liquid-filled damper of the present invention, since the equilibrium water content of the viscous liquid enclosed in the damper body is limited to a certain ratio or less, it is possible to limit the volume expansion based on the contained moisture to a certain ratio. Thus, it is possible to prevent a decrease in damping characteristics and a decrease in durability due to volume expansion. The equilibrium water content refers to the water content when the moisture contained in a certain substance has reached an equilibrium state with the surrounding environment.

  The structure of the viscous liquid-enclosed damper of the present invention is not particularly limited, and is applicable to all types of conventionally known viscous liquid-enclosed dampers.

  For example, as a general structure, a damper body includes a container body and a lid body, and a lid body may be joined in a state where the container body is filled with a viscous liquid. And a lid made of a rubber-like elastic body, both of which are vulcanized and adhered, and the container body is formed by integrally molding a soft resin such as a thermoplastic elastomer and a hard resin, or by molding the whole with a soft resin, and forming the lid with a hard resin. Or made of a soft resin, and both are bonded or ultrasonically welded.

  The material of the container body and the lid is appropriately selected in consideration of the required flexibility, mechanical strength, moldability, bondability between them, and swelling resistance to a viscous liquid.

  On the other hand, the type of the viscous liquid is not particularly limited as long as the damping characteristics can be obtained, and a conventionally used liquid can be used. In general, silicone oil is used, and examples thereof include silicone oil in which solid particles or powder for improving damping characteristics are dispersed.

  Here, in the present invention, the equilibrium water content of the viscous liquid is controlled to 0.2% or less, preferably 0.1% or less, more preferably 0.05% or less.

  Moisture contained in the viscous liquid expands by calculation about 3400 times at 80 ° C. and about 1700 times at 100 ° C. by vaporization. However, since it is actually enclosed in the damper body, the damper The damper body expands depending on the thermal expansion property and elastic deformation property of the body. Therefore, in practice, although it depends on the material and thickness of the damper main body, when the filling amount of the viscous liquid, that is, the filling rate is almost 100%, the equilibrium water content is 0 regardless of the volume of the damper main body. If it is 0.2% or less, the volume expansion of the damper body due to heat can be suppressed within about 1.3 times.

  The method for controlling the equilibrium water content is not particularly limited, and if the equilibrium water content of the viscous liquid immediately after production is within the above-described range, the viscous liquid may be filled under conditions or conditions where the equilibrium water content does not increase. In addition, if the equilibrium water content is higher than the above range, a viscous liquid may be used after performing a treatment for reducing the water content by various methods. The method for reducing the water content is not particularly limited, and for example, distillation, dehydration under reduced pressure, or the like may be employed.

  As described above, according to the present invention, since the equilibrium moisture content of the viscous liquid is controlled within a certain range, volume expansion under high temperature conditions is prevented, and durability and vibration damping properties particularly under high temperature conditions are improved. This has the effect of providing a viscous liquid-enclosed damper.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a cross-sectional view of a viscous liquid-filled damper according to an embodiment of the present invention after assembly.

  In FIG. 1, a viscous liquid sealing damper 1 is obtained by ultrasonically welding a lid 5 to a container body 4 in which a soft resin portion 2 and a hard resin portion 3 are integrally formed. Is enclosed. The soft resin portion 2 has a bellows-like projection 2a at the center, and a shaft insertion portion 2b, which is a concave portion, is formed in the projection 2a, and the shaft insertion portion 2b has a supported member. It has a structure in which ten shafts 11 are fitted. The viscous liquid 6 sealed in the container body 4 has a function of absorbing vibration between the lid 5 and the shaft 11.

  Such a viscous liquid-filled damper 1 was manufactured as follows.

  First, after the hard resin part 3 is molded, the soft resin part 2 is integrally molded to obtain the container body 4.

  Next, the viscous liquid 6 is injected into the container body 4 manufactured in this manner. Thereafter, the container body 4 and the lid 5 are joined together by ultrasonic welding to form a viscous liquid-filled damper 1.

(Example 1)
A viscous liquid-filled damper filled with silicone oil stored in a low humidity environment was used as a viscous liquid. When the equilibrium water content of the filled silicone oil was measured by the Karl Fischer method, it was about 0.18%.

The volume expansion coefficients of the viscous liquid-filled damper 1 under the 80 ° C. environment and under the 100 ° C. environment were measured as shown in FIG. That is, using a universal rheometer Dynalyzer 2000 (manufacturer: Reologica Instruments AB), the viscous liquid-filled damper 1 is sandwiched between the plates 20, and the pressure applied to the damper is made constant at 1.0 × 10 ⁻² N. Then, the plate was allowed to stand at an ambient temperature of 80 ° C. and 100 ° C. for 2 hours, and the gap width g between the plates 20 which was widened due to the increase in the pressure applied to the plates 20 due to the expansion of the damper as the temperature increased was measured. At this time, the protruding portion 2a of the soft resin portion 2 of the container body 4 was expanded with the bellows extended as shown in the figure. Therefore, when the volume was calculated by roughly estimating the volume in a substantially cylindrical state and compared with the original volume, the volume expansion rates were about 1.2 times at 80 ° C. and about 1.3 times at 100 ° C.

(Example 2)
A viscous liquid-filled damper in which silicone oil subjected to vacuum dehydration treatment was enclosed as a viscous liquid was used. When the equilibrium water content of the filled silicone oil was measured by the Karl Fischer method, it was about 0.09%.

  When the viscous liquid-filled damper 1 was placed in an environment of 80 ° C. and 100 ° C., it was in an expanded state, but the bellows of the protruding portion was not completely expanded, and the volume expansion was greatly reduced. It became clear.

(Comparative Example 1)
A viscous liquid-filled damper in which silicone oil left in a normal environment was enclosed as a viscous liquid was used. When the equilibrium water content of the filled silicone oil was measured by the Karl Fischer method, it was about 0.32%.

  When this viscous liquid-filled damper was placed in an environment of 80 ° C. and 100 ° C., it was in an expanded state, but the protruding portion swelled in a spherical shape, and the shaft insertion portion was crushed and deformed, so that it could not be used practically. .

(Example 3)
A viscous liquid-filled damper filled with silicone oil that had been heated and dehydrated under reduced pressure was used as a viscous liquid. When the equilibrium water content of the filled silicone oil was measured by the Karl Fischer method, it was about 0.021%.

(Example 4)
A viscous liquid-filled damper filled with silicone oil stored in a low humidity environment was used as a viscous liquid. When the equilibrium water content of the filled silicone oil was measured by the Karl Fischer method, it was about 0.085%.

(Example 5)
A viscous liquid-filled damper in which silicone oil stored under an environment of 65% humidity was enclosed as a viscous liquid was used. When the equilibrium water content of the filled silicone oil was measured by the Karl Fischer method, it was about 0.18%.

(Comparative Example 2)
A viscous liquid-filled damper was filled with silicone oil stored in an environment of 85% humidity as a viscous liquid. When the equilibrium water content of the filled silicone oil was measured by the Karl Fischer method, it was about 0.27%.

(Comparative Example 3)
The viscous liquid-filled damper was filled with the hydrated silicone oil as a viscous liquid. When the equilibrium water content of the filled silicone oil was measured by the Karl Fischer method, it was about 0.69%.

(Test Example 1) Measurement of tan δ Using a universal rheometer Dynalyzer 2000 (manufacturer: Reologica Instruments AB), the viscous liquid-filled dampers 1 of Examples 3 and 4 and Comparative Example 3 were sandwiched between the plates 20 ( The temperature was changed from 130 ° C to 150 ° C. The gap width g between the plates 20 is increased by the expansion of the damper due to the temperature rise and the pressing force on the plate 20 being increased, but the pressing force on the plate 20 is kept constant (1.0 × 10 ⁻² N). Tan δ (1 Hz) was measured by Universal Rheometer Dynalyzer 2000. The results are shown in FIG.

  As a result, in Examples 3 and 4, particularly in Example 3, tan δ was higher than that in Comparative Example 3. Therefore, it was found that when the equilibrium water content of the viscous liquid was low, tan δ was increased, and the vibration damping performance was improved. At 130 ° C. or lower, the tan δ could not be measured accurately because it overlapped with the expansion of the damper.

(Test Example 2) Measurement of Pressure Contact Force Using a universal rheometer Dynalyzer 2000 (manufacturer: Relogica Instruments AB), the viscous liquid-filled dampers 1 of Examples 3 to 5 and Comparative Examples 2 to 3 were placed between the plates 20. And the temperature was changed to about 80 ° C. to 150 ° C. (see FIG. 2). The gap width g between the plates 20 increases due to the expansion of the damper with the rise in temperature and the increase in the pressure contact force on the plate 20, but the pressure contact force on the plate 20 is measured with the gap width g kept constant. did. The results are shown in FIGS. FIG. 5 is an enlarged view of Examples 3 and 4 and Comparative Example 3 in FIG.

  As a result, in Examples 3 to 5 having a low equilibrium moisture content, the pressure contact force was generally lower than that in Comparative Examples 2 to 3, and particularly at 80 to 95 ° C. where the use condition was high, as shown in FIG. As the water content decreased, the pressing force also decreased. Therefore, it was found that when the equilibrium water content of the viscous liquid was low, the pressure contact force was low, and the force with which the viscous liquid-enclosed damper was pressed against the device was weak.

(Test Example 3) Durability test Each of the viscous liquid-filled dampers of Examples 3 to 5 and Comparative examples 2 to 3 was attached to an actual machine (M-X087, manufactured by Chuo Denshi Kogyo) three times and left at 90 ° C for 40 minutes. did. Thereafter, the temperature was 90 ° C., the acceleration was 3G, the frequency was 10 to 30 Hz, and the vibration direction was the vertical direction (Z-axis direction). The oil was leaked from the viscous liquid-filled damper every 10 minutes. The test was terminated when oil leakage was confirmed, that is, when the viscous liquid-filled damper was broken. Table 1 shows the results.

  As shown in Table 1, it was confirmed that the lower the equilibrium water content of the viscous liquid, the better the durability of the viscous liquid-filled damper.

It is sectional drawing of the viscous liquid sealing damper which concerns on one Embodiment of this invention. It is a figure showing the state where the volume expansion coefficient etc. of the viscous liquid enclosure damper of one embodiment of the present invention were measured. FIG. 9 is a view showing a measurement result of Test Example 1. FIG. 9 is a view showing a measurement result of Test Example 2. FIG. 9 is a view showing a measurement result of Test Example 2.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 Viscous liquid enclosed damper 2 Soft resin part 3 Hard resin part 4 Container main body 5 Lid part 6 Viscous liquid 10 Supported body 11 Shaft 20 Plate

Claims (8)

A viscous liquid-filled damper in which a viscous liquid is sealed inside a damper body, wherein the equilibrium water content of the viscous liquid is 0.2% or less. The viscous liquid-filled damper according to claim 1, wherein an equilibrium water content of the viscous liquid is 0.1% or less. 3. The viscous liquid-filled damper according to claim 1, wherein the damper main body comprises a container main body and a lid, and both are joined by ultrasonic welding or adhesion. The viscous liquid-filled damper according to any one of claims 1 to 3, wherein the viscous liquid is silicone oil. The damper according to any one of claims 1 to 4, wherein the viscous liquid is sealed after being dehydrated under reduced pressure. In a method of manufacturing a viscous liquid-enclosed damper in which a viscous liquid is enclosed in a damper main body, a step of setting an equilibrium water content of the viscous liquid to 0.2% or less, and a step of filling the viscous liquid into the damper main body. A method for producing a viscous liquid-enclosed damper, comprising: 7. The method according to claim 6, wherein an equilibrium water content of the viscous liquid is set to 0.1% or less. The method according to claim 6 or 7, wherein the equilibrium moisture content of the viscous liquid is reduced by dehydration under reduced pressure.

Images