WO2007066468A1 - Optical disk device - Google Patents

Abstract

An optical disk device (21) has a housing (22), a traverse chassis (23) for supporting a motor that drives an optical disk, an elastic member (24) for supporting the traverse chassis (23) from the direction in horizontal to the housing (22), a spindle motor (25), and an optical-pickup holder (26). The elastic member (24) is installed between the housing (22) and the traverse chassis (23) such that it is longer than its natural length by an amount corresponding to an elongation ratio ΔL.

Description

Specification

optical disc device

Technical field

[0001] The present invention relates to an optical disc device installed in a personal computer, a DVD recorder, etc.

Background technology

[0002] As a conventional optical disc device, for example, an optical disc device 1 as shown in FIG. 9 is known. This optical disk device 1 includes a traverse chassis 4 and a dynamic damper 5 supported on the bottom wall of a casing 2 (only a portion of which is shown in FIG. 9) via an elastic member 3, and a dynamic absorber 5 disposed on the traverse chassis 4. A spindle motor 6 and an optical pickup holder 7 are provided.

[0003] As shown in FIG. 10, the elastic member 3 is a cylindrical member having constrictions 3a, 3b, and 3c at three locations. A dynamic damper 5 is attached to each of the four constrictions 3c of the traverse chassis.

[0004] In the optical disk device 1 having the above configuration, a disk (not shown) attached to a spindle motor 6 rotates, and an optical pickup holder 7 having an optical pickup (not shown) moves to a predetermined position. , read information on the disk.

[0005]Here, if the center of gravity of the disk and the center of rotation are shifted by attaching a label or the like to the disk, the traverse chassis 4 vibrates due to the biased centrifugal force generated during rotation. Therefore, as a means to suppress this vibration, a dynamic vibration absorber 5 is provided. This dynamic vibration absorber 5 can cancel the vibration of the traverse chassis 4 by vibrating in the opposite direction to the traverse chassis 4.

[0006] Another example of a conventional optical disc device is described in Japanese Patent No. 3684710. As shown in FIG. 11, the optical disc device 11 described in the publication includes a main chassis 12, a sub-chassis 14 which is also supported by a horizontal force on the main chassis 12 by a vibration isolator 13, and is arranged on the sub-chassis 14. The disc drive means 15 and the information recording/reproducing means 16 are provided. Further, it is stated that the vibration isolator 13 is installed in a state where it is compressed from its natural length. [0007] The optical disc device 1 having the above configuration needs to be equipped with a dynamic vibration absorbing mechanism and a canceler motor to suppress vibrations, which is a cause of increased manufacturing costs. Further, as shown in FIG. 9, when the traverse chassis 4 is vertically supported by the housing 2, there is a problem that the characteristics change greatly due to changes in the attitude of the optical disk device 1. Furthermore, as optical disk devices have become faster in recent years, optical disk devices 1 and 11 are required to further improve their anti-vibration performance.

Disclosure of invention

[0008] Accordingly, an object of the present invention is to provide an optical disc device that is low cost and can effectively suppress vibrations that occur during rotation.

[0009] The optical disc device according to the present invention includes a housing, a traverse chassis that supports a motor that drives the optical disc, and an elastic member that horizontally supports the traverse chassis in the housing. Then, the elastic member is installed in a state where it is stretched by an elongation rate A L from its natural length.

[0010] As in the above configuration, by supporting the traverse chassis on the housing with the elastic member stretched in a horizontal direction, it is possible to suppress the vibration of the optical disc device without using a dynamic vibration absorption mechanism or a canceller motor. Become.

[0011] Furthermore, since this optical disc device does not require a dynamic vibration absorbing mechanism, a canceller motor, etc. to prevent vibration, the number of parts can be reduced. As a result, a reduction in manufacturing costs can be expected.

[0012] Preferably, the elongation rate A L of the elastic member is 0.05≤A L≤0.2. When the elongation ratio is less than 0.05, almost no vibration damping effect is observed. On the other hand, if the elongation ratio exceeds 0.2, there is a risk that the housing or traverse chassis cannot be held properly due to deformation of the elastic member, so it is desirable to install within the above range.

[0013] Preferably, the traverse chassis has a rectangular shape including long sides and short sides, and the elastic member is attached to the long sides. The center of rotation of the disk follows an elliptical orbit with the long axis intersecting the long side of the traverse chassis, so by attaching an elastic member to the long side of the traverse chassis, vibrations of the optical disk device can be suppressed more effectively. can.

[0014] For example, the elastic members are arranged at two locations on each of a pair of long sides of the traverse chassis. It will be done. This makes it possible to stably hold the traverse chassis in the housing.

[0015] According to the present invention, it is possible to obtain an optical disc device that effectively suppresses vibrations generated during rotation and that exhibits small changes in characteristics due to changes in posture. Furthermore, since a dynamic vibration absorption mechanism, canceller motor, etc. are not required, the number of parts can be reduced, and as a result, manufacturing costs can be reduced.

Brief description of the drawing

[0016] FIG. 1 is a perspective view of an optical disc device according to an embodiment of the present invention.

[Figure 2] A diagram showing a state before attachment of the elastic member used in Figure 1.

FIG. 3 is a diagram showing a state in which the elastic member used in FIG. 1 is attached.

FIG. 4 is a diagram showing an optical disc device according to another embodiment of the present invention.

[Figure 5] Test results for confirming the effects of the present invention are diagrams comparing an optical disk in which the housing and traverse chassis are supported vertically and an optical disk in which the casing and traverse chassis are supported horizontally.

FIG. 6 is a diagram showing the relationship between the elongation rate of the elastic member and the amount of internal vibration of the optical disc device, showing test results for confirming the effects of the present invention.

FIG. 7 is a diagram showing the relationship between the loss coefficient of the elastic member and the amount of internal vibration of the optical disc device, showing test results for confirming the effects of the present invention.

FIG. 8 is a diagram showing the relationship between the hardness of the elastic member and the amount of internal vibration of the optical disc device, showing test results for confirming the effects of the present invention.

FIG. 9 is a perspective view of a conventional optical disc device.

[FIG. 10] A cross-sectional view of the elastic member used in FIG. 9.

FIG. 11 is a diagram showing another example of a conventional optical disc device.

BEST MODE FOR CARRYING OUT THE INVENTION

[0017] An optical disc device 21 according to an embodiment of the present invention will be described with reference to FIGS. 1 to 3.

[0018] FIG. 1 is a perspective view of the optical disc device 21. The optical disc device 21 includes a housing 22 having a side wall 22a, a traverse chassis 23, and an elastic member 24 that supports the traverse chassis 23 on the housing 22. [0019] The traverse chassis 23 has a rectangular shape including a pair of long sides 23a and a pair of short sides 23b, and supports a spindle motor 25 that drives an optical disk and an optical pickup holder 26. This traverse chassis 23 is horizontally attached to the side wall 22a of the housing 22 by elastic members 24 arranged at four locations, two on each of the pair of long sides 23a.

[0020] FIG. 2 and FIG. 3 are diagrams showing the state before and after the elastic member 24 is attached. Referring to FIG. 2, the elastic member 24 has a barrel-shaped extension part 24a that can be expanded and contracted in the axial direction, waist parts 24b, 24c which are annular grooves on both sides of the extension part 24a, and waist parts 24b, 24c. It has a cylindrical shape including flanges 24d and 24e on the outside. Further, the elastic member 24 is made of a thermosetting elastic body or a thermoplastic elastic body having a loss coefficient tan δ≥0.8 and a hardness Hs≤40 degrees.

[0021] The housing 22 and the traverse chassis 23 are provided with through holes corresponding to the constrictions 24b and 24c of the elastic member 24, the constriction 24b is provided with the housing 22, and the constriction 24c is provided with the traverse chassis. 23 can be installed each. At the time of installation, the extension portion 24a is installed in a state in which it is extended from its natural length, as shown in FIG. At this time, the expansion rate A L of the expansion section 24a is set within the range of 0.05≤A L≤0.2. In this specification, "elongation rate A L" refers to the natural length L of the elongated portion and the length after elongation! Let Δ L= (same L) refer to the value found by ZL.

[0022] In the optical disk device 21 having the above configuration, a disk (not shown) attached to a spindle motor 25 rotates, and an optical pickup holder 26 having an optical pickup (not shown) is placed in a predetermined direction in the left and right direction in the figure. Move to the location and read the information on the disc. At this time, by supporting the horizontal force of the traverse chassis 23 against the housing 22 by the stretched elastic member 24, it is possible to suppress vibrations caused by the rotation of the disk without using a dynamic vibration absorption mechanism or canceller motor. becomes. Furthermore, compared to conventional optical disk devices, it is possible to obtain an optical disk device whose characteristics change less due to changes in posture.

[0023] Next, the results of tests conducted to confirm the effects of the optical disc device 21 having the above configuration will be described with reference to FIGS. 5 to 8.

[0024] First, FIG. 5 shows a conventional optical disk device having a dynamic vibration absorption mechanism (indicated by ◊ in the figure), a conventional optical disk device without a dynamic vibration absorption mechanism (indicated by △ in the figure), and the present invention. For each of the related optical disk devices 21 (indicated by a circle in the figure), TRACK when the disk rotates. FIG. 7 is a diagram showing the results of measuring the amount of internal vibration in the ING direction. Note that the "TRACKING direction" refers to the moving direction of the optical pickup holder 26 in FIG.

[0025] Referring to FIG. 5, the optical disc device 21 according to the present invention has a reduced amount of internal vibration compared to a conventional optical disc device that does not have a dynamic vibration absorption mechanism, and this effect is effective in the rotation range of 6000 rpm or more. This is particularly noticeable. Further, when comparing the optical disc device 21 according to the present invention with a conventional optical disc device having a dynamic vibration absorption mechanism, the amount of vibration was almost the same in each rotational speed range. This confirmed that the optical disc device 21 according to the present invention can suppress internal vibrations without using a dynamic vibration absorption mechanism.

[0026] Next, FIG. 6 shows the optical disc device 21 according to the present invention, in which the elongation rate A L of the elastic member during assembly is 0% (indicated by ◊ in the figure), 3% (indicated by B in the figure), and 5%. % (indicated by * in the figure) and 20% (indicated by △ in the figure), and shows the results of measuring the amount of internal vibration during disk rotation.

[0027] Referring to Figure 6, the optical disk devices with the elongation rate A L of 0% and 3% obtained almost the same measured values in each rotational speed range, and there was no discernible difference in the amount of internal vibration between the two. Rare na power tsuta. On the other hand, in an optical disk device with an elongation rate A L of 5%, compared to an optical disk device with an elongation rate A L of 3% or less, the effect of reducing the amount of internal vibration becomes greater as the disk rotates at higher speeds around 4500 rpm. This was confirmed. In addition, the optical disk device with an elongation rate A L of 20% was found to have an effect of reducing the amount of internal vibration in each rotation range compared to the optical disk device with an elongation rate A L of 3% or less.

[0028] Also, from this result, it is considered that the larger the elongation rate A L of the elastic member is, the more the amount of internal vibration is reduced. However, in the elastic member 24 shown in Fig. 2, if the elongation rate A L exceeds 20%, the flanges 24d and 24e may deform and may not be able to properly hold the housing 22 or the traverse chassis 23. ≤0.2 is desirable.

[0029] Next, FIG. 7 shows that in the optical disc device 21 according to the present invention, the loss coefficient tan δ of the elastic member is 0.1 (indicated by squares in the figure) and 0.4 (indicated by squares in the figure). ), 0.8 (indicated by △ in the figure), respectively, and shows the results of measuring the amount of internal vibration during disk rotation. In this specification, "loss coefficient" is a value that indicates how much energy a material absorbs when it is deformed, and is a value that indicates how much energy a material absorbs when it is deformed, and is a value that indicates the storage shear modulus (G') and the loss shear modulus (G'). ") ratio, G"ZG ' shall refer to '.

[0030] Referring to FIG. 7, when the loss coefficient tan δ of the elastic member was 0.1 or 0.4, no large difference was observed in the amount of internal vibration in each rotational speed range. On the other hand, when the loss coefficient tan δ was 0.8, the effect of reducing the amount of internal vibration in each rotational speed range was observed compared to other optical disk devices. This confirmed that the larger the loss coefficient tan δ of the elastic member, the greater the effect of reducing the amount of internal vibration.

[0031] Next, FIG. 8 shows that in the optical disc device 21 according to the present invention, the hardness Hs of the elastic member is set to 30 degrees (indicated by ◊ in the figure), 40 degrees (indicated by B in the figure), and 50 degrees (indicated by B in the figure). FIG. 12 is a diagram showing the results of measuring the amount of internal vibration during disk rotation with each setting (indicated by △). In this specification, "hardness Hs" refers to hardness measured by the JIS spring method.

[0032] Referring to Figure 8, an optical disk device with hardness Hs of 40 degrees has a lower vibration amount in the high rotation range of the disk of 4500 rpm or more than an optical disk device with hardness Hs of 50 degrees. A reduction effect was observed. Furthermore, the optical disc device with hardness Hs of 30 degrees was found to be more effective in reducing the amount of vibration in each rotational speed range compared to other optical disc devices. This confirmed that the lower the hardness Hs of the elastic member, the greater the effect of reducing the amount of internal vibration.

[0033] Next, an optical disc device 31 according to another embodiment of the present invention will be described with reference to FIG. The optical disc device 31 includes a housing 32, a traverse chassis 33, an elastic member 34, a spindle motor 35, and an optical pickup holder 36, and the elastic member 34 is connected to a pair of long sides 33a of the traverse chassis 33, respectively. They are placed at three locations in total, one on each side and one on one short side 33b, and support the traverse chassis 33 horizontally on the housing 32 in a state where it is extended beyond its natural length. Note that the other configurations are the same as the optical disc device 21 shown in FIG. 1, so explanations will be omitted.

[0034] When the disk rotates, a larger centrifugal force acts in the direction intersecting the long side 23a of the traverse chassis 23, so in the optical disk device 21 shown in FIG. 1, the elastic member 24 is arranged on the long side 23a. The elastic member 24 may be placed at any position where the traverse chassis 23 can be held stably and horizontally with respect to the housing 22 without being limited thereto. For example, the elastic members may be provided at four locations, two on each of the pair of short sides, or may be provided on each of the long and short sides as shown in FIG. [0035] In addition, the optical disc device 21 having the above configuration has a dynamic vibration absorbing mechanism installed in order to reduce the number of parts. By attaching a filter, it is expected that the amount of internal vibration will be further reduced.

[0036]Also, in each of the above embodiments, an example is shown in which both sides of the traverse chassis are attached to the housing using elastic members, but the present invention is not limited to this, and one end side is attached to the housing. The structure may be such that the traverse chassis is integrated with the traverse chassis, and the casing and the traverse chassis are connected at the other end using an elastic member.

[0037] Furthermore, in each of the above embodiments, an example was shown in which only the elongated portion of the elastic member is elongated, but the present invention is not limited to this, and a structure in which the entire elastic member is elongated may be used. Further, in each of the above embodiments, an example is shown in which the housing and the traverse chassis are attached to the constriction of the elastic member, but the invention is not limited to this, and these may be attached in any manner that can stably hold them. ,.

[0038] In addition, in each of the above embodiments, the force shown as an example of a hollow elastic member is not limited to this, for example, a solid elastic member may be used, or an elastic force that includes a plurality of material forces is not limited to this. A member may also be used.

[0039] Further, as the elastic member 24, a "thermosetting elastic body (rubber)" or a "thermoplastic elastic body (thermoplastic elastomer)" may be used. Specifically, "thermosetting elastomer (rubber)" includes natural rubber, butadiene rubber, styrene butadiene rubber, acrylonitrile butadiene rubber, isoprene rubber, chloroprene rubber, butyl rubber, halogenated butyl rubber, ethylene propylene rubber, chloro Examples include sulfonated polyethylene, chlorinated polyethylene, acrylic rubber, fluororubber, urethane rubber, and silicone rubber.

[0040] As the "thermoplastic elastomer", thermoplastic elastomers such as styrene-based thermoplastic elastomers, olefin-based, polyester-based, polyurethane-based, vinyl chloride-based, polyamide-based, etc. are used. can.

[0041] The embodiments of the present invention have been described above with reference to the drawings. The present invention is not limited to the illustrated embodiments. Various modifications and variations can be made to the illustrated embodiments within the same scope or equivalent scope of the present invention. Industrial applicability

This invention can be advantageously used in optical disc devices installed in personal computers, DVD recorders, and the like.

Claims

The scope of the claims [1] Housing and a traverse chassis that supports a motor that drives an optical disk; an elastic member that supports the traverse chassis on the housing with a horizontal force, the elastic member being attached in a state where it is extended by a predetermined elongation rate ΔL from its natural length. [2] The optical disk device according to claim 1, wherein the elongation rate A L of the elastic member is 0.05≤A L≤0.2. [3] The traverse chassis has a rectangular shape including a pair of long sides and a pair of short sides, The optical disc device according to claim 1, wherein the elastic member is attached to the long side. [4] The optical disc device according to claim 3, wherein the elastic members are arranged at two locations on each of the pair of long sides of the traverse chassis.