KR20080005330A - Dynamic vibration absorber and optical disk apparatus using the same - Google Patents

Abstract

A dynamic vibration absorber and an optical disk apparatus using the same are provided to preclude vibration absorbing efficiency from being lowered by releasing compressive force generated between first and second contact parts through a pressure relief area. A dynamic vibration absorber(10) is attached to a main chassis(18) for supporting a motor for driving an optical disk with an attaching pin(20). The dynamic vibration absorber includes a cylindrical elastic body having through holes(16), and dynamic vibration absorbing devices(17). The attaching pin has a shaft(22) and a head part larger than the shaft at one end of the shaft. The elastic body has an attaching pin supporting part, first and second contact parts(12a,12b), and a pressure relief area. The attaching pin supporting part supports the shaft of the attaching pin. The pressure relief area is arranged to the attaching pin supporting part to relieve compressive force generated between the first and second contact parts. The pressure relief area is a recessed part arranged to a surface opposed to the shaft of the attaching pin of the elastic body.

Description

DYNAMIC VIBRATION ABSORBER AND OPTICAL DISK APPARATUS USING THE SAME

Field of technology

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copper reducer and an optical disc apparatus using the same, and more particularly, to a copper reducer in which a resonance frequency does not change and an optical disc apparatus using the same.

Prior art

Optical disc devices for driving optical discs such as CDs, CD-ROMs, DVDs, DVD-ROMs, optical media such as magneto-optical discs, and large capacity FDs are disclosed in, for example, Japanese Patent Application Laid-Open No. 2001-256762 (Patent Document 1) It is disclosed in 355670 (patent document 2). FIG. 5 is a perspective view showing main parts of the optical disk devices disclosed in Patent Documents 1 and 2, and FIG. 6 is a cross-sectional view of a portion indicated by VI-VI in FIG.

5 and 6, the optical disk device 110 includes a main body 111, a main damper 112 provided at four circumferences of the main body 111, and a main chassis supported by the main damper 112 ( 108). On the main chassis 108, a spindle motor 114 for rotating the optical disk 109, a head 115 for reading the optical disk 109, and a sub damper 101 are provided, and the sub damper 101 is provided. The copper reducer 107 is supported. Here, the copper reducer 100 includes the copper reducer 107 and the sub damper 101.

Patent Document 1: Japanese Patent Laid-Open No. 2001-256762 (described in FIG. 1 and related thereto)

Patent Document 2: Japanese Patent Application Laid-Open No. 2001-355670 (described in Fig. 3 and related thereto)

FIG. 7 is an enlarged view of a portion indicated by 에서 in FIG. 6. Referring to FIG. 7, the sub damper 101 constituting the copper reducer 100 has a cylindrical shape, and is formed by the head 103a of the attachment pin 103 attached to the main chassis 108 and the main chassis 108. Convex parts 102a and 102b which are end faces of the cylinder are supported. The pin support part 104 which abuts on the attachment pin 103 in the center part of the inner periphery of the sub damper 101 is provided. Moreover, the recessed part 105 for supporting the copper reducer 107 is provided in the center part of the outer peripheral part.

Originally, since the vibration reducer 100 is designed to suppress a predetermined vibration, when the sub damper 101 is attached to the main chassis 108 by the attachment pin 103, the sub damper 101 is designed to the designed dimension. ) Needs to be attached. However, since the length of the attachment pin 103 is not necessarily constant, the amount of compression which compresses the sub damper 101 changes with the length of the attachment pin 103 because the length of the attachment pin 103 changes. That is, when the length of the attachment pin 103 becomes short, reaction force as shown by the arrow A in FIG. 7 arises in the sub damper 101, and a compressive force is applied to the pin support part 104. FIG. At the same time, the reaction force of the sub damper 101 pressing the attachment pin 103 changes in response to the compressive force, so that the frictional force of the surface between the pin support portion 104 and the attachment pin 103 of the sub damper 101 changes. . As a result, the stiffness of the inner diameter part of the sub damper 101, such as the pin support part 104 and the recessed part 105, changes. Thereby, there exists a problem that the resonance frequency of the copper reducer 100 shifts with respect to the drive rotation speed of an optical disk apparatus, and the vibration absorption efficiency of the copper reducer 100 falls.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a copper reducer in which vibration absorption efficiency is not deteriorated and an optical disk device using the same.

The copper reducer according to the present invention is attached to a main chassis that supports a motor for driving an optical disk via an attachment pin. The copper reducer includes a cylindrical elastic body having a through hole through which the attachment pin is inserted, and the copper reducer supported by the elastic body, wherein the attachment pin is provided at one end of the shaft and the shaft and has a face wider than the shaft. Has The elastic body is adapted to axially pass both an attachment pin support portion for supporting an axis of the attachment pin, a first contact portion abutting the head of the attachment pin, a second contact portion abutting the main chassis, and a first and second contact portion. It has a pressure relief area | region provided in an attachment pin support part so that it may cross | intersect at least one part of an extended virtual strip | belt, and reliefs the compressive force which arises between a 1st and 2nd abutment part.

Since the elastic body has a pressure relief region provided to intersect at least a portion of the first abutting portion against the head of the attachment pin and an imaginary band extending axially through both the first abutting portion against the main chassis. The compression force generated between the first and second abutments does not affect the elastic body, and the resonance frequency at the time of design does not change.

As a result, it is possible to provide a copper reducer in which the vibration absorption efficiency is not lowered.

Preferably, the pressure relief region does not stress the attachment pin support at the boundary of the non-contact portion between the attachment pin support and the attachment pin.

Moreover, preferably, the pressure relief area | region is a recess provided in the surface which opposes the axis | shaft of the said attachment pin of an elastic body.

According to one Embodiment of this invention, the surface which opposes the axis | shaft of the attachment pin between the recessed part of an elastic body, and a 1st contact part or a 2nd contact part has a space between attachment pins.

The concave portion may be an annular groove, and a plurality of the annular grooves may be provided at intervals from each other in the axial direction of the attachment pin. In addition, a member that is more flexible than the elastic body may be inserted in the recess.

Also preferably, the pressure relief region may include a portion where the elastic body has different strengths in the axial direction of the attachment pin, or may block the transmission of pressure in the axial direction.

In another aspect of the present invention, the optical disk uses the above-described copper reducer.

According to the above configuration, it is possible to provide a copper reducer in which vibration absorption efficiency is not deteriorated and an optical disk device using the same.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described with reference to drawings. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing a state in which a sub damper (elastic material) constituting a copper reducer of an optical disk apparatus according to the present invention is supported on a main chassis with attachment pins, which corresponds to the conventional Fig. 7.

Referring to FIG. 1, in the copper reducer 10 according to this embodiment, the shaft 22 of the attachment pin 20 penetrates through the inner circumference of the cylindrical sub damper 11 to main the sub damper 11. It is attached to the chassis 18. An attachment pin support portion 14 is formed in the center of the inner circumference of the sub damper 11 that abuts on the shaft 22 of the attachment pin 20. The copper oscillator 17 is supported by the recessed part 15 provided in the center part of the outer periphery of the sub damper 11. As shown in FIG. In addition, the contact portion 12a provided at the upper end of the sub-damper 11 abuts against the lower end 21a of the head 21 of the attachment pin 20, and the contact portion 12b provided at the lower end of the sub-damper 11. Abuts against the top surface 18a of the main chassis 18. These points are the same as that of FIG.

This embodiment differs from the prior art in that recesses, such as annular grooves 13a and 13b, are provided in the upper and lower portions of the attachment pin support 14 at the inner circumferential portion of the sub-damper 11.

Here, the annular grooves 13a and 13b are abutting portion 12a (first abutting portion) which abuts the head 21 of the attachment pin of the sub damper 11, and the main chassis 18 of the sub damper 11. Abutment 12b (second abutment) abuts across the imaginary band (part indicated by a in FIG. 1) that extends through both the first and second abutments in the axial direction of the attachment pin 20. It is provided. In this case, the annular grooves 13a and 13b cross the entire virtual band. However, the ring grooves 13a and 13b are not limited to this and may cross at least a part of the virtual band.

Thus, even if the annular groove 13a, 13b formed in the attachment pin support part 14 is shorter than the designed dimension of the axial dimension of the attachment pin 20, even if it is made to compress the sub damper 11 to the axial direction, It acts as a pressure relief area that reliefs that force. That is, the compressive force is not applied to the attachment pin support part 14 by these annular grooves 13a and 13b, and the sub damper 11 is attached to the attachment pin support part 14 by the attachment pin support part 14 with the same force as design. The shaft 22 of the 20 is supported, and the recessed part 15 supports the copper reducer 17 with the same force as the design.

In addition, although the annular groove provided in the inner peripheral part of a contact part was demonstrated as an example as a pressure relief area here, it is not limited to this, The 1st contact part 12a which abuts on the head 21 of an attachment pin, At least the second contact portion 12b abutting the main chassis 18 and the virtual band a extending so as to pass both of the first and second contact portions 12a and 12b in the axial direction of the attachment pin 20. Any shape may be used as long as it is provided so as to traverse and can release the compressive force generated between the first and second abutment portions. In addition, although two annular grooves 13 were provided above and below the sub damper 11 here, not only this but any one may be sufficient.

In addition, this groove | channel does not need to be provided continuously, may be provided intermittently, or may be a cavity part. Moreover, if it exists in the inner peripheral part of a contact part, you may extend to the outer peripheral part.

In addition, the surface facing the shaft 22 of the attachment pin 20 between the annular grooves 13a and 13b and the first and second abutment portions 12a and 12b is disposed between the attachment pin 20. It has space in, but this may not be necessary.

Next, the operation of the pressure relief region described above will be described. Fig. 2 is a CAE (computer aided engineering) showing a state of generation of stress in a copper reducer in one embodiment of the present invention shown in Fig. 1 and a copper reducer in the conventional example shown in Fig. 7. Drawing created by Here, in each case, it is a figure which shows the stress at the time of compressing by 0.2 mm with the attachment pin 20, and attaching. 2 (A) shows the case of the present invention, and FIG. 2 (B) shows the conventional example. In addition, here, the copper reducer is shown rotated 90 degrees for ease of understanding.

First, referring to FIG. 2 (B), according to the conventional example, in the convex portions 102a and 102b of the sub-damper 101, a portion 25 to which high stress is applied exists, and the sub-damper 101 At both ends of the pin support 104 at the center, there is a portion 26 to which low stress is applied. That is, the strength of the pin support part 104 which abuts on an attachment pin receives an external stress, and differs from the strength originally designed.

On the other hand, referring to FIG. 2 (A), according to the copper reducer according to the embodiment of the present invention, in the contact portions 12a and 12b of the sub-damper 11, high stress is generated similarly to FIG. 2 (B). Although the part 25 to be applied exists, the part 26 to which low stress is applied is only the inside part of the groove | channel of the annular groove 13a, 13b. No stress is applied at the boundary between the pin supporting portion 14 where the central portion of the sub-damper 11 abuts against the attachment pin and the annular grooves 13a and 13b, that is, the non-contact portion between the attachment pin. Therefore, the sub damper 11 can exhibit a predetermined design capability.

Next, the effect of this invention is demonstrated. FIG. 3 is a view for explaining the difference between the conventional example shown in FIG. 7 and the effect in the embodiment of the present invention shown in FIG. 1. Fig. 3 (A) is a diagram showing the relationship between the frequency and the resonance magnification when the copper reducer is attached to an attachment pin of a normal length in the copper reducer of the present invention, and Fig. 3 (B) shows the present invention. It is a figure which shows the relationship between the frequency and resonance magnification in the case of length increase of 0.1 mm in a copper reducer. 3 (C) and 3 (D) are diagrams corresponding to FIG. 3 (A) and FIG. 3 (B) in the conventional copper reducer.

Referring to Figs. 3C and 3D, in a conventional copper reducer, when the attachment length by the attachment pin is 0.1 mm long, the resonance frequency f0 is changed from 181.10 Hz to 173.60 Hz. The rate of change of the resonance frequency is (181.10-173.60) /181.10 = 0.041, which is about 4.1%. On the other hand, according to the copper reducer of this invention, when the attachment length by an attachment pin becomes 0.1 mm long, the resonance frequency f0 changes from 190.10Hz to 189.12Hz. The rate of change of the resonance frequency is (190.10-189.12) /190.10 = 0.0052, which is about 0.5%. That is, according to the present invention, the rate of change of the resonance frequency is reduced to about 1/10 as compared with the conventional example.

Next, another embodiment of the present invention will be described. Fig. 4A is a diagram showing another embodiment of the copper reducer according to the present invention. Referring to FIG. 4A, in this dynamic reducer 30, the shaft 22 of the attachment pin 20 penetrates the inner circumference of the cylindrical sub damper 31 in the same manner as in the previous embodiment. The damper 31 is attached to the main chassis 38. Attachment pin support parts 34a and 34b which are divided up and down the inner circumference of the sub-damper 31 and abut on the shaft 22 of the attachment pin are formed, and a recess 36 is provided therebetween. The copper reducer 37 is supported by the concave portion 35 provided in the center portion of the outer circumference of the sub damper 31. In addition, the contact portion 32a (first contact portion) provided at the upper end portion of the sub-damper 31 abuts against the lower end portion 21a of the head 21 of the attachment pin 20, and the lower end portion of the sub-damper 31. The provided contact portion 32b (second contact portion) abuts on the upper surface 38a of the main chassis 38.

Also in this embodiment, annular grooves 33a and 33b are provided in the attachment pin support portions 34a and 34b that support the attachment pin 20 at the inner circumferential portion of the sub-damper 31.

The annular grooves 33a and 33b are the contact portions 32a and 32b of the sub damper 31 which abuts the head 21 of the attachment pin 20 and the main chassis 38, and the contact portions 32a and 32b. Any shape may be used as long as it is provided to cross at least a part of the virtual band a extending to pass both of them in the axial direction of the attachment pin 20, and the compressive force generated between the abutting portions can be relief.

In addition, although two annular grooves 33 were provided above and below the sub damper 31 here, not only this but any one may be sufficient as it. In addition, as shown in Fig. 4B, in addition to the annular grooves 33a and 33b, the attachment between the annular grooves 33a and 33b and the first and second abutment portions 32a and 32b. If spaces 39a and 39b are provided between the shafts 22 on the surface of the fin 20 opposite to the shafts 22, a larger effect can be obtained.

In addition, as shown in FIG. 4 (C), it does not have the annular groove shown in FIG. 4A, but has only the concave portion 36 that does not join the shaft 22 of the attachment pin 20. Cases are also considered. However, in this case, the recessed part 36 is not provided in the attachment pin support part which supports the attachment pin 20 like FIG. 4 (A). Therefore, such recessed part 36 does not correspond to the pressure relief area mentioned here.

In addition, in FIG.4 (B) and (C), the same code | symbol is attached | subjected about the same part as FIG.4 (A), and although it is different from FIG.4 (A), it shows in the corresponding part in FIG.4 (A). Reference numerals added with 100 are assigned to one reference numeral, and description thereof is omitted.

Moreover, in the said embodiment, although the pressure relief area | region like an annular groove was provided in the area | regions other than an attachment pin support part, it is not limited to this, The member which is more flexible than a sub damper is provided in the pressure relief area | region like an annular groove | channel. You may insert it.

In addition, the pressure relief region may be a portion having different strengths in which the sub-damper is provided in the axial direction of the attachment pin. That is, the pressure relief region may be a region that blocks the transfer of pressure in the axial direction of the attachment pin.

Although an embodiment of the present invention has been described with reference to the drawings, the present invention is not limited to the illustrated embodiment. Various modifications can be made to the illustrated embodiment within the same range as the present invention or within an equivalent range.

Since the vibration absorber efficiency does not fall, the copper reducer according to the present invention can be advantageously used in an optical disk device or the like using the same.

BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing of the copper reducer which concerns on one Embodiment of this invention.

Fig. 2 is a diagram showing a state of occurrence of stress in a copper reducer when the present invention is compared with the conventional example.

3 is a view for explaining the effect of the copper reducer according to the present invention.

4 is a view showing a copper reducer according to another embodiment of the present invention.

Fig. 5 is a perspective view showing the main part of the optical disk device.

FIG. 6 is a cross-sectional view of the portion shown as VI-VI in FIG. 5. FIG.

Figure 7 is a cross-sectional view showing a conventional copper reducer.

(Explanation of symbols for the main parts of the drawing)

10, 30: copper reducer

11, 31: sub damper

12, 32: contact part

13, 33: home

14, 34: attachment pin support

15, 35: recess

16: through hole

17, 37: copper reducer

18, 38: main chassis

20: attachment pin

21: tofu

22: axis

Claims (7)

In the copper reducer which is attached to the main chassis which supports the motor which drives an optical disk through an attachment pin, The copper reducer includes a cylindrical elastic body having a through hole through which the attachment pin is inserted, and the copper reducer supported by the elastic body. The attachment pin has a shaft and a head which is provided at one end of the shaft and has a surface wider than the shaft, The elastic body, An attachment pin support for supporting an axis of the attachment pin; A first contact portion abutting the head of the attachment pin; A second abutting portion in contact with the main chassis, Provided on the attachment pin support to traverse at least a portion of the virtual strip that extends both in the axial direction through the first and second abutments, and reliefs the compressive force generated between the first and second abutments. Has a pressure relief zone, The said pressure relief area | region is a recess provided in the surface which opposes the axis | shaft of the said attachment pin of the said elastic body, A surface facing the axis of the attachment pin between the recess and the first contact portion or the second contact portion of the elastic body has a space between the attachment pins. In the copper reducer which is attached to the main chassis which supports the motor which drives an optical disk through an attachment pin, The copper reducer includes a cylindrical elastic body having a through hole through which the attachment pin is inserted, and the copper reducer supported by the elastic body. The attachment pin has a shaft and a head which is provided at one end of the shaft and has a surface wider than the shaft, The elastic body, An attachment pin support for supporting an axis of the attachment pin; A first contact portion abutting the head of the attachment pin; A second abutting portion in contact with the main chassis, Provided on the attachment pin support to traverse at least a portion of the virtual strip that extends both in the axial direction through the first and second abutments, and reliefs the compressive force generated between the first and second abutments. Has a pressure relief zone, The said pressure relief area | region is a recess provided in the surface which opposes the axis | shaft of the said attachment pin of the said elastic body, The concave portion is a copper reducer, characterized in that the ring-shaped groove. The method of claim 2, The annular groove is a plurality of grooves in the axial direction of the attachment pins are characterized in that the plurality of drills are spaced apart. In the copper reducer which is attached to the main chassis which supports the motor which drives an optical disk through an attachment pin, The copper reducer includes a cylindrical elastic body having a through hole through which the attachment pin is inserted, and the copper reducer supported by the elastic body. The attachment pin has a shaft and a head which is provided at one end of the shaft and has a surface wider than the shaft, The elastic body, An attachment pin support for supporting an axis of the attachment pin; A first contact portion abutting the head of the attachment pin; A second abutting portion in contact with the main chassis, Provided on the attachment pin support to traverse at least a portion of the virtual strip that extends both in the axial direction through the first and second abutments, and reliefs the compressive force generated between the first and second abutments. Has a pressure relief zone, The said pressure relief area | region is a recess provided in the surface which opposes the axis | shaft of the said attachment pin of the said elastic body, And said flexible member is inserted into said recessed portion. In the copper reducer attached to the main chassis for supporting the motor for driving the optical disk through the attachment pin, The copper reducer includes a cylindrical elastic body having a through hole through which the attachment pin is inserted, and the copper reducer supported by the elastic body. The attachment pin has a shaft and a head which is provided at one end of the shaft and has a surface wider than the shaft, The elastic body, An attachment pin support for supporting an axis of the attachment pin; A first contact portion abutting the head of the attachment pin; A second abutting portion in contact with the main chassis, Provided on the attachment pin support to traverse at least a portion of the virtual strip that extends both in the axial direction through the first and second abutments, and reliefs the compressive force generated between the first and second abutments. Has a pressure relief zone, And said pressure relief region comprises a portion having different strengths provided in the axial direction of said attachment pin of said elastic body. In the copper reducer attached to the main chassis for supporting the motor for driving the optical disk through the attachment pin, The copper reducer includes a cylindrical elastic body having a through hole through which the attachment pin is inserted, and the copper reducer supported by the elastic body. The attachment pin has a shaft and a head which is provided at one end of the shaft and has a surface wider than the shaft, The elastic body, An attachment pin support for supporting an axis of the attachment pin; A first contact portion abutting the head of the attachment pin; A second abutting portion in contact with the main chassis, Provided on the attachment pin support to traverse at least a portion of the virtual strip that extends both in the axial direction through the first and second abutments, and reliefs the compressive force generated between the first and second abutments. Has a pressure relief zone, The pressure relief region cuts off the transmission of pressure in the axial direction. As a copper reducer attached to the main chassis supporting a motor for driving an optical disk through an attachment pin, The copper reducer includes a cylindrical elastic body having a through hole through which the attachment pin is inserted, and the copper reducer supported by the elastic body. The attachment pin has a shaft and a head which is provided at one end of the shaft and has a surface wider than the shaft, The elastic body, An attachment pin support for supporting an axis of the attachment pin; A first contact portion abutting the head of the attachment pin; A second abutting portion in contact with the main chassis, Provided on the attachment pin support to traverse at least a portion of the virtual strip that extends both in the axial direction through the first and second abutments, and reliefs the compressive force generated between the first and second abutments. An optical disk apparatus using a copper reducer having a pressure relief region.

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