JPH0562443A - Multiaxial anisotropic damper for vibration insulation and recording/reproducing device - Google Patents

Abstract

PURPOSE:To obtain the damper having a Coulomb damper effect by coupling a rugged friction generating part provided within the recess of the recessed part of a container and a connecting part connecting the hollow recessed part to the outside. CONSTITUTION:An exterior part 6 and a displacement part 2 are formed of rubber elastic materials which are soft enough to allow displacement. A silicone oil 5 is packed into the container of the recessed part and ruggedness of about 50mum in diameter and 100mum in height is provided on the inner side of the displacement part 2. Large friction is generated between the microrugged part of the displacement part and the oil 5 when a vertical vibration is applied in this constitution. The damper utilizing the loss by such friction is called Coulomb damper. The Coulomb damper characteristic attenuates in vibration in proportion to the square of vibration frequencies and the resonance at f0 is extremely small an excellent multiaxial integral type damper having an excellent vibration insulation characteristic is attained with a small size by utilizing such phenomena.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibration damping damper. The present invention also relates to a recording / reproducing apparatus using the damper.

[0002]

2. Description of the Related Art In recent years, recording / reproducing apparatuses have been remarkably spread, and their applications for use in an environment such as a car where vibration is severe are increasing.

An example of the damper described above will be described below with reference to the drawings. FIG. 3 shows an example of a conventional viscous damper. In the figure, 31 is a hollow elastic body (rubber) in which silicone oil 35 is contained. The displacement portion 32 is inserted into the concave portion of the elastic body 31, and the displacement portion 32 and the lower portion of the attachment portion 34 are attached to the vibration-isolated portion and the housing of the device (not shown), respectively.

In the above structure, when the displacement portion 33 moves,
Resonance can be suppressed by viscous loss (internal loss) of silicon oil flowing inside.

This viscous damper has the effect of suppressing resonance in the three axial directions, is very convenient, and is widely used. The vibration damping characteristics of this viscous damper are as shown in FIG. The horizontal axis of the figure is the vibration frequency, and the vertical axis is the damping rate (X ₁ / X ₀ , X ₁ :
Vibration of the vibration-isolated portion, X ₀ : disturbance vibration).

That is, it has resonance (size Q) at the frequency f ₀ , and vibrations between f _{0 and} Qf ₀ are attenuated in proportion to the square of the frequency. However, at frequencies above Qf ₀ , the vibration is attenuated in proportion to the first power of the frequency. Since the vibration isolation performance deteriorates due to the resonance of f _0, the size Q is made as small as possible in practical use. Then, in fact, it is attenuated only by the first power at frequencies above f ₀ .

[0007]

In principle, the conventional viscous damper can only obtain the vibration damping characteristics shown in FIG.

In view of the above problems, the present invention provides a vibration damping damper that suppresses resonance to a small extent and has a large damping rate.

[0009]

In order to solve the above problems, a vibration damping damper according to the present invention comprises a concave container filled with a liquid inside and small irregularities provided inside the recess of the concave portion of the container. The friction generating part and the connecting part for connecting to the outside are connected to the concave portion.

Further, the recording / reproducing apparatus of the present invention has a spring for elastically supporting the vibration-isolated portion and a friction generating portion having small irregularities inside the recess of the concave portion of the concave container filled with the liquid. A multi-vibration damper for vibration damping having a connecting portion for connecting to the outside provided in a concave portion is attached so as to suppress resonance of the spring.

The characteristic of the above-mentioned vibration isolating multi-axis damper is a resonance suppressing effect utilizing a so-called Coulomb damper effect, which is different from a loss occurring in a viscous substance such as rubber, caused by friction between substances. The unevenness of the friction generating portion has a size of several tens of μm to several mm. In order to have an effect on minute vibrations, such very small unevenness is necessary. number
The friction part of the complex unevenness in which the unevenness of several tens μm is formed on the size of mm is effective for a wide vibration amplitude.

The above recording / reproducing apparatus has a mechanical recording / reproducing mechanism such as an optical disk recording / reproducing apparatus typified by a compact disk player and other magnetic recording / reproducing apparatus. The anti-vibration portion is a portion in the recording / reproducing apparatus that needs to be particularly anti-vibration, and is a portion where the recording / reproducing mechanism is assembled. This part is generally subjected to insulation vibration (vibration isolation) from the housing.

[0013]

With the above-described structure, the present invention enables a multi-axis anti-vibration damper that exhibits a damping factor of a power of 1 or more with respect to a direction in which a large vibration damping factor is required.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An anti-vibration multi-axis damper according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing an embodiment of the present invention. In the figure, 1 is a top mounting portion, 2 is a displacement portion,
Reference numeral 4 is a bottom surface mounting portion, 6 is an exterior, and 7 is a displacement portion, which is made of a rubber elastic body that is soft enough to be deformed.
Silicon oil 5 is filled in these concave containers. The displacement part 2 includes a support part 3 on the bottom surface mounting part 4.
Are joined by. Inside the displacing portion 2 (the side in contact with the silicone oil), irregularities having a diameter of approximately 50 μm and a height of 100 μm are provided.

In the above structure, when vertical vibration is applied, large friction is generated between the minute irregularities of the displacement portion and the silicone oil. A damper that utilizes such a loss due to friction is called a Coulomb damper. In the conventional example shown in FIG. 3, of course, there is friction loss in addition to viscous loss, but the resonance suppression characteristics of the coulomb damper rapidly exerts its effect above a certain loss (see "Vibration Isolation / Shocker Design" Ohmsha). The conventional configuration has no effect.

FIG. 2 shows the principle characteristics of the Coulomb damper. The horizontal axis of the figure is the frequency, and the vertical axis is the vibration damping rate. Vibration is attenuated in proportion to the square of the frequency. Further, the resonance at f ₀ is extremely small.

In the structure of this embodiment, the vibration damping ratio is approximately proportional to the 1.5th power of the frequency and does not reach the second power. However, this difference is practically large.

FIG. 5 is a diagram showing another embodiment of the damper of the present invention. FIG. 5 is an improvement of the uneven pattern of the friction generating portion of the displacement portion of the embodiment of FIG. Reference numeral 51 denotes a large friction generating portion having a large shape, which is a large uneven portion, and has a diameter of 5
The height is 00 μm and the height is 1 mm. 52 is a small friction generating portion having a small shape, and the shape is the same as that of the embodiment of FIG. Basically, this embodiment is different from the embodiment of FIG.
The area of the friction portion increases. Furthermore, it has the characteristic that Coulomb damper characteristics are easily obtained at low vibration frequencies. In the case of the present embodiment, the attenuation characteristic which is proportional to the square of the frequency was obtained.

FIG. 6 shows a recording / reproducing apparatus using the anti-vibration multi-axis damper of the present invention. In the figure, 61 is a vibration-proof part,
Reference numeral 62 denotes a housing, and the vibration-isolated portion 61 has springs 63, 64, 6
5, 66 are supported in the up, down, left, and right (front and back) directions. Reference numeral 67 is a vibration-proof multi-axis damper of the present invention, which is attached so as to have a Coulomb damper effect in the vertical direction. Although only one damper is shown in the drawing, a plurality of miniaturized dampers are actually used in order to minimize the vibration allowance of the support portion.

As described above, the recording / reproducing apparatus of the present invention uses the damper utilizing friction loss, and is small in size and has excellent vibration damping characteristics.

[0022]

As described above, according to the present invention, an excellent multi-axis integrated damper can be realized by realizing the damper having the Coulomb damper effect.

[Brief description of drawings]

FIG. 1 is a schematic diagram illustrating an outline of a vibration-proof multi-axis damper according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram illustrating vibration damping characteristics of the vibration isolation multi-axis damper of FIG.

FIG. 3 is an explanatory diagram illustrating a conventional viscous damper.

FIG. 4 is an explanatory diagram illustrating a conventional viscous damper.

FIG. 5 (a) is a schematic view for explaining another embodiment of the anti-vibration multi-axis damper of the present invention.

FIG. 6 is a schematic diagram illustrating a recording / reproducing apparatus according to an embodiment of the present invention.

[Explanation of symbols]

 1 Upper surface mounting part 2 Displacement part 3 Support part 4 Lower surface mounting part 5 Silicon oil 6 Exterior 7 Deformation part

Claims (2)

[Claims] 1. A container having a concave shape filled with liquid, a frictional generating portion having small irregularities provided inside the recess of the concave portion of the container, and a connecting portion for connecting the outside to the concave portion. Anti-vibration multi-axis damper. 2. A spring for elastically supporting a vibration-isolated portion, and a friction generating portion having a small unevenness inside the concave portion of a concave portion of a concave flexible container filled with a liquid inside the concave portion. A recording / reproducing apparatus mounted so as to suppress the resonance of the spring by a vibration isolating multi-axis damper having a connecting portion for connecting to the outside.