JPH1182583A - Precision part supporting plate spring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide excellent damping performance for a precision part by providing a multilayer structure comprising two or more layers in which metal plates and visco-elastic layered bodies are alternately stacked. SOLUTION: A precision part supporting plate spring (plate spring) is a layered product of a three layer structure in which metal plates 8 are stacked on both sides of a visco-elastic layered body 7 to be integrated with each other. The metal plate 8 may be a metal plate used as an ordinary plate spring. The thickness of the metal plate 8 is not especially limited, but generally it is preferably set to 10-200 μm. As a forming material for the visco-elastic layer body 7, there is no limitation, but a silicone compound is suitable because it little changes in damping characteristic to the change in the atmosphere temperature. Further, it is preferable to mix a filler in the silicone compound to give an effect of further improving the damping characteristic. Thus, it is possible to obtain such a good damping effect of absorbing transmission of vibration to a precision part by the plate spring to be remarkably reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a precision component supporting leaf spring capable of supporting a precision component such as a head of a disk drive and preventing transmission of vibration to the precision component.

[0002]

2. Description of the Related Art In a storage disk device such as an optical disk drive or a magneto-optical disk drive for driving a recording disk to rotate, a head unit for reading and writing information includes a head 1 such as a magnetic head and an optical head as shown in FIG. And a leaf spring 2 supporting the same. Reference numeral 3 denotes a mounting block for fixing the leaf spring 2.

[0003] The head section receives wind pressure due to distortion of the disk when the disk rotates, and vibrations from the outside such as a drive device for the head 1 and a motor for driving the disk to rotate. SUS
Plate), a leaf spring 2 formed of a beryllium copper plate or the like is deformed, and the position of the head 1 is shifted, so that a reading error or a writing error is likely to occur.

In order to reduce or eliminate the vibration in the leaf spring 2, a vibration damping material 4 having a structure shown in FIG. 5 and having a laminated structure of a restraining body 5 and a viscoelastic layered body 6 is shown in FIG. As described above, a method of sticking to the leaf spring 2 has been proposed (Japanese Patent Publication No. 4-8868). According to this method, the viscoelastic layered body 6 sandwiched between the vibrating leaf spring 2 and the restraining body 5 is deformed by the vibration deformation of the leaf spring 2 to generate internal resistance (molecular friction), and Since the energy is converted into heat energy, the vibration damping effect that the vibration energy directly received by the leaf spring 2 is greatly reduced is obtained.

[0005]

However, when the damping member 4 formed by laminating the above-described restraining member 5 and the viscoelastic layered body 6 is used as described above, the damping member 4 is used as the leaf spring 2. Must be attached to the product, resulting in poor productivity and high cost.
Further, the damping material 4 cannot be stuck to the entire surface of the leaf spring 2 to be stuck without any gap, and as a result, the damping property is inferior.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a precision component supporting leaf spring having excellent vibration damping properties for precision components.

[0007]

In order to achieve the above object, a precision component supporting leaf spring according to the present invention is provided between a precision component and a fixing portion to elastically support the precision component. In this case, a metal plate and a viscoelastic layered body have a multilayer structure of two or more layers alternately stacked.

[0008]

Next, an embodiment of the present invention will be described.

As an example of the precision component supporting leaf spring (hereinafter abbreviated as "leaf spring") of the present invention, for example, as shown in FIG. A laminated body having an integrated three-layer structure can be given.

The metal plate 8 is not particularly limited as long as it is a metal plate conventionally used as a leaf spring.
For example, it is common to use stainless steel (SUS), beryllium copper, or the like. In particular, SUS is suitably used in that it has a high elastic modulus and high corrosion resistance.

The thickness of the metal plate 8 is not particularly limited, but is usually preferably set to 10 to 200 μm. That is, if the thickness is too thin, such as less than 10 μm, it becomes difficult to support the head, and if the thickness is more than 200 μm, the modulus of elasticity is too high to be practical as a leaf spring. However, the thickness of the metal plate 8 varies depending on the weight and size of the head to be supported.

As a material for forming the viscoelastic layered body 7,
Although there is no particular limitation, a silicone compound having a small change in vibration damping characteristics with respect to a change in ambient temperature is preferably used. The silicone compound may be a general adhesive, a gel, or a mixture thereof.

Further, it is preferable that a filler is added to the above-mentioned silicone compound in order to give an effect of further improving vibration damping properties. Examples of the filler include, but are not particularly limited to, plastic beads such as acrylic resin and styrene resin, and inorganic fillers such as silica powder and alumina powder. Also, the shape of the filler is not particularly limited, and various shapes such as a spherical shape and an amorphous shape are used, but an amorphous shape having a large surface area is preferable because it is more excellent in vibration damping characteristics. And since this filler acts as a spacer at the time of punching, the average particle diameter is preferably in the range of 10 to 100% with respect to the thickness of the viscoelastic layered body 7, and more preferably. 30-80%.

The amount of the filler is not particularly limited, but may be 100 parts by weight (hereinafter, "parts") of the silicone compound.
) Is preferably set in the range of 1 to 200 parts, more preferably 10 to 60 parts. That is, if the compounding amount of the filler is less than 1 part, a sufficient effect of improving the vibration damping properties cannot be expected, and the filler may not sufficiently fulfill the role of a spacer at the time of punching. This is because, when the ratio exceeds, the viscoelastic layered body 7 becomes hard, and the vibration damping characteristics tend to deteriorate.

The thickness of the viscoelastic layered body 7 is not particularly limited, but is usually preferably set to 5 to 150 μm. That is, if the thickness is less than 5 μm,
It is difficult to obtain sufficient damping characteristics, and if it is thicker than 150 μm,
This is because it is not practical as a leaf spring and tends to have poor punching workability.

The leaf spring of the present invention can be obtained as follows, for example, in the case of a three-layer structure. First, two metal plates and one viscoelastic layered body are prepared, and two metal plates are respectively disposed on both sides of the viscoelastic layered body. Next, a leaf spring having a three-layer structure can be obtained by laminating and integrating them by an appropriate method. As the method of laminating and integrating, specifically, a method in which the above-mentioned arrangement is passed through a pair of opposed rubber rolls and pressed, or a method in which a metal plate is arranged and then pressed by a press And the like.

Further, in addition to the above-mentioned production method, it can be obtained by the following method. That is, first, a viscoelastic layered body forming material is applied to one side of a metal plate so as to have a predetermined thickness, and crosslinked and dried to produce a laminate having a two-layer structure of the metal plate and the viscoelastic layered body. I do. Then, a metal plate is provided on the surface of the viscoelastic layered body of the laminated body and laminated and integrated by an appropriate method, whereby a leaf spring having a three-layer structure can be obtained. As described above, as a method of laminating and integrating, as described above, a metal plate is disposed on the viscoelastic layered body surface of the two-layered laminated body, and then passed between opposed rubber rolls and pressed. And a method of arranging a metal plate and then pressing with a press.

The leaf spring obtained as described above has a three-layer laminated structure of a metal plate / viscoelastic layer / metal plate in which metal plates are laminated and integrated on both sides via a viscoelastic layer. However, the present invention is not limited to this, and it is sufficient if at least two layers of a metal plate and a viscoelastic layer are provided. Therefore, the metal plate and the viscoelastic layer are alternately laminated.
A laminate having a multilayer structure of at least two layers may be used. For example, FIG.
As shown in FIG. 3, a viscoelastic layered body 7 is laminated on both sides of a metal plate 8 as a center, and a metal plate 8 is laminated on each surface of the viscoelastic layered body 7 to form a five-layer laminated body. Leaf spring. As the leaf spring of the present invention, a laminated body in which the metal plates 8 are disposed on both outermost surfaces, which are the outermost layers of the leaf spring, is particularly preferable in terms of excellent vibration damping characteristics. From the relation of the total thickness of the springs and the like, a leaf spring composed of a laminate having a three-layer structure of the metal plate 8 / viscoelastic layered body 7 / metal plate 8 shown in FIG. 1 and the metal plate 8 / viscoelasticity shown in FIG. Layered body 7 / metal plate 8 / viscoelastic layered body 7
A leaf spring composed of a laminated body having a five-layer structure of the metal plate 8 is preferable.

Although the total thickness of the leaf spring of the present invention is not particularly limited, it is 25 μm to 1000 μm (= 1 mm).
Is more preferable, and more preferably 40 to 150 μm.

The leaf spring of the present invention is used, for example, as follows. That is, as shown in FIG. 3, the head 1 is supported by using the leaf spring 9 of the present invention instead of the two conventional leaf springs, and the other end of the leaf spring 9 is attached and fixed to the mounting block 3. You.

Next, examples will be described together with comparative examples.

[0022]

Embodiment 1 A stainless steel plate (SUS30) having a thickness of 25 μm
On one side of 4), a silicone-based pressure-sensitive adhesive (TSR1510, manufactured by Toshiba Silicone Co., Ltd.) was applied to a thickness of 50 μm. Then, after forming a silicone-based viscoelastic layered body by crosslinking at 130 ° C. × 10 minutes and drying, a stainless steel plate (SUS304) having a thickness of 25 μm is disposed on the surface of the viscoelasticized layered body. Then, by passing between the opposed rubber rolls, a laminated sheet (100 μm in thickness) was obtained. Then, the obtained laminated sheet was punched into a 2 mm square by a high-speed press to obtain a target leaf spring. The silicone-based pressure-sensitive adhesive used was a filler in which 20 parts of amorphous silica having an average particle size of 30 μm was blended as a filler.

[0023]

Embodiment 2 A 25 μm-thick stainless steel plate (SUS30
On one side of 4), a silicone adhesive (X-40-3004A, manufactured by Shin-Etsu Chemical Co., Ltd.) was applied to a thickness of 25 μm. Then, after forming a silicone-based viscoelastic layered body by crosslinking at 130 ° C. × 10 minutes and drying, a stainless steel plate (SUS304) having a thickness of 25 μm is disposed on the surface of the viscoelasticized layered body. Then, the sheet was passed between opposed rubber rolls to obtain a laminated sheet (thickness: 75 μm). Then, the obtained laminated sheet was punched into a 2 mm square by a high-speed press to obtain a target leaf spring. Note that no filler is blended in the silicone-based pressure-sensitive adhesive.

[0024]

Example 3 A silicone-based pressure-sensitive adhesive having an average particle size of 50
A mixture containing 20 parts of μm amorphous silica was used.
Otherwise, a leaf spring was obtained in the same manner as in Example 1.

[0025]

Example 4 As a silicone-based pressure-sensitive adhesive, an average particle size of 5 μm was used.
m was mixed with 20 parts of amorphous silica. Otherwise, a leaf spring was obtained in the same manner as in Example 1.

[0026]

Comparative Example 1 A stainless steel plate (SUS30) having a thickness of 25 μm
4) An acrylic double-sided pressure-sensitive adhesive (No. 5911, manufactured by Nitto Denko Corporation) was superposed on the sheet 4) so as to have a thickness of 125 μm, and passed between two pinch rolls to obtain a laminated sheet having a two-layer structure. Then, the obtained laminated sheet was punched into a 2 mm square by a high-speed press to obtain a vibration damping material.

[0027]

Comparative Example 2 A 50 μm thick stainless steel plate (SUS304) was used as a leaf spring.

The product of the above embodiment was incorporated as a leaf spring for holding a pickup lens of an optical disk device. Further, the product of Comparative Example 1 was attached to the surface of a leaf spring holding a pickup lens of an optical disk device.
The product of Comparative Example 2 was used as it was as a leaf spring for holding the pickup lens of the optical disk device.
Then, the items shown in Table 1 below were evaluated, and the results were summarized in the same table. In addition, about each evaluation item, it evaluated according to the following method.

[Vibration Suppression Characteristics] The product of the embodiment and the product of the comparative example were actually incorporated in an optical disk device as described above,
The vibration generated at Hz was detected by an FFT analyzer (manufactured by Advantest). As a result, based on Comparative Example 2, the following evaluation was performed on the assumption that the more the vibration decreased, the better the vibration suppression characteristics were. ◎: reduction of 20 dB or more ○: reduction of 10 dB or more and less than 20 dB ：: reduction of less than 10 dB ×: no reduction in vibration

[Adhering workability] When the embodiment product and the comparative product are actually incorporated into an optical disc apparatus as described above, those requiring a sticking operation to a leaf spring or the like are indicated by x and x.
Those that did not require a sticking operation were evaluated as ○.

[Punching workability] When the above-described example and comparative examples were punched into a leaf spring for holding a pickup lens of an optical disk device, those having no protrusion of the viscoelastic layered body were evaluated as good. It evaluated as x. The product of Comparative Example 2 was not evaluated because it was made only of SUS304.

[Comprehensive Evaluation] The overall evaluation was made according to the following criteria. ◎: at least one ◎, and the rest having a rating of ○: all having a rating of ×: having at least two ratings of ×

[0033]

[Table 1]

From the above Table 1, it can be seen that the working examples in which the leaf spring is directly incorporated in the optical disk device as the head support does not require any sticking work, so that the workability at the time of its use is good. The vibration characteristics were also excellent. Above all, Examples 1, 3, and 4 having a silicone-based viscoelastic layered product containing amorphous silica were particularly excellent in vibration damping properties. In addition, all the products of the examples had no problem in terms of the punching workability, and the work was performed favorably without the viscoelastic layered material protruding when punched. On the other hand, in Comparative Example 1 in which a vibration damping material composed of a stainless steel plate and an acrylic pressure-sensitive adhesive was adhered to a leaf spring, the work was inferior because the adhering work was required. Was also inferior to the above examples. Further, it is natural that Comparative Example 2 in which the stainless steel plate is used as it is as the leaf spring has the lowest vibration damping characteristics.

[0035]

As described above, since the leaf spring of the present invention has a multilayer structure of two or more layers in which a metal plate and a viscoelastic layer are alternately laminated, the transmission of vibration to precision parts is performed. It is excellent in damping effect that it is absorbed by the leaf spring and greatly reduced. Moreover, in the leaf spring of the present invention, a vibration damping material is attached to the surface of a leaf spring made of a metal plate as in the related art in order to elastically support the precision part by interposing between the precision part and the fixing part. There is no need for such a sticking operation.

In the leaf spring of the present invention, when the viscoelastic layered body is formed of a silicone compound, the silicone compound has little change in vibration damping characteristics due to environmental temperature.
A stable vibration damping effect can be exhibited.

When a viscoelastic layered body is formed from a mixture of the above silicone compound and a filler,
It is more preferable that the filler has more excellent vibration damping characteristics, and that the filler functions as a spacer when punching into a leaf spring shape. When the filler has an average particle diameter in the range of 10 to 100% of the thickness of the viscoelastic layered body,
It is even more preferable in terms of improving the vibration damping characteristics and the effect as a spacer.

As the leaf spring of the present invention, it is particularly preferable to use a laminated body having a three-layer structure in which metal plates are laminated on both sides of the viscoelastic layered body from the viewpoint of the total thickness in actual use. .

The leaf spring of the present invention can be used, for example, in a storage disk device for rotatingly driving a recording disk such as an optical disk drive or a magneto-optical disk drive. It is particularly useful as a leaf spring for supporting the plate spring. Vibration received from a fixed portion to which the leaf spring is attached can be significantly reduced or eliminated, and errors in reading and writing by the head can be effectively prevented.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an example of a configuration of a leaf spring of the present invention.

FIG. 2 is an explanatory view showing another example of the configuration of the leaf spring of the present invention.

FIG. 3 is an explanatory diagram showing a configuration in a state where the leaf spring of the present invention is incorporated in a disk device.

FIG. 4 is an explanatory diagram showing a configuration of a head unit of a conventional disk device.

FIG. 5 is an explanatory diagram showing a configuration of a conventional vibration damping material.

FIG. 6 is an explanatory view showing a state in which the vibration damping material is attached to a leaf spring.

[Explanation of symbols]

 7 Viscoelastic layered body 8 Metal plate

Claims (6)

[Claims] 1. A precision component supporting leaf spring interposed between a precision component and a fixing portion for elastically supporting the precision component, comprising at least two layers in which a metal plate and a viscoelastic layer are alternately laminated. A precision component supporting leaf spring having a multilayer structure. 2. The precision component supporting leaf spring according to claim 1, wherein said viscoelastic layered body is formed of a silicone compound. 3. The precision component supporting leaf spring according to claim 2, wherein a filler is compounded in the silicone compound. 4. The precision component supporting leaf spring according to claim 3, wherein the average particle diameter of the filler is in a range of 10 to 100% of the thickness of the viscoelastic layered body. 5. The precision component supporting leaf spring is a laminate having a three-layer structure in which metal plates are laminated on both surfaces thereof via a viscoelastic layered body. Precision parts supporting leaf spring. 6. The precision component supporting leaf spring according to claim 1, wherein the precision component is a head of a disk drive.