JP2001110175A - Optical disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical disk device having a structure capable of reducing a whistling sound caused by the rotation of a disk. SOLUTION: The optical disk device is provided with a housing having a top board 1B, the inner surfaces of which are faced oppositely inside this housing. The inner surface area of this top board 1B is stuck with a sheet having rugged patterns and a sound absorbing effect. These patterns are defined to be a number of crescent patterns arranged in the direction running reverse to the direction of an air-flow generating on a disk surface. The rugged patterns facilitate the separation of an air layer from the disk surface, thereby reducing the noise then caused.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk device, and more particularly to an improvement in an optical disk device in which wind noise generated when an optical disk is driven is reduced.

[0002]

2. Description of the Related Art Due to the large storage capacity of an optical disk, that is, a CD-ROM, an optical disk device, particularly a CD-ROM drive, has been developed as a main peripheral device of a personal computer, and its data reading speed has been increasing rapidly. It is getting bigger. In general, as a method of increasing the data reading speed, a method of increasing the rotation speed of the disk is adopted, and the reference rotation speed of the initial disk drive (220
Assuming that the rpm is 1, the current 10-times speed (2200
(rpm) or higher is common, and 20x speed (4
400 rpm) is now on the market, and recently it is being developed to a 40-times speed (8800 rpm).

[0003]

As the rotation speed of the disk increases, the wind noise generated by the rotation of the disk gradually increases, which is a main factor of the noise source of the disk drive. In a conventional optical disk device, as a measure for suppressing this noise, measures are taken to increase the hermeticity of the disk drive so that no gap is formed in the housing of the disk drive and to confine the noise generated inside the enclosure.

The noise of this disk drive is a single speed,
That is, when the rotation speed is lower than 10 times speed (2200 rpm), the user is not particularly worried.
At a rotation speed of 0 × speed or more, especially 20 × speed or more, a loud noise is generated, and reduction of the noise is demanded.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide an optical disk apparatus having a structure capable of reducing wind noise generated by rotation of a disk. .

It is another object of the present invention to prevent a disk from being deformed or lifted during rotation with an increase in the rotation speed of the disk, and to reduce wind noise generated by the rotation of the disk. The present invention provides an optical disk device having the following.

[0007]

According to the present invention, there is provided a housing having a top plate, a disk rotating mechanism for rotatably holding a disk in the housing, and a housing. An optical disk drive having a mounting mechanism for loading a disk into the body and taking out the disk from the housing, when the disk is loaded, an uneven pattern is formed in a region of the inner surface of the top plate portion facing the disk. An optical disk device is provided.

Further, according to the present invention, a housing having a top plate, a disk rotating mechanism for rotatably holding a disk in the housing, and loading a disk in the housing, And a mounting mechanism for taking out the disk, when the disk is loaded, an uneven pattern is formed in a region of the inner surface of the top plate portion facing the disk, and this pattern is formed by an air flow generated on the disk surface. There is provided an optical disc device characterized by a number of extension patterns arranged in a direction rotating in a direction opposite to the direction.

The inventors have noticed that the wind noise generated with the high-speed rotation of the disk is a noise generated when an air layer on the surface of the disk being rotated is separated from the surface. It is presumed that the noise can be reduced by causing the peeling to occur smoothly, and irregularities are provided on the inner surface of the top plate of the disk drive in order to cause the peeling to occur smoothly. In particular, the unevenness is formed on a sheet having a sound absorbing effect, and when the sheet is attached to the inner surface of the top plate of the disk drive, not only a mere air layer is smoothly separated, but also noise generated by the separation is brought close to its source. Sound can be absorbed in the defined area.

Further, when the disk is rotated at a high speed, an air flow is generated between the disk and the top plate, and when this air flow flows out of the disk to the periphery due to centrifugal force, a negative pressure is generated on the disk periphery. The negative pressure may cause the disk to warp or float. However, by providing unevenness on the inner surface of the top plate of the disk drive, the pressure distribution on the disk caused by the air flow is relatively uniform, and the disk is prevented from floating or warping.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the optical disk apparatus according to the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of an optical disk device, that is, a disk drive, schematically showing a state in which a drawer 2 is pulled out from a housing (cabinet) 1. The housing (cabinet) 1 has a box shape in which the drawer 2 is pulled out, and has a bottom shape. The bottom housing (bottom cabinet) 1A and a top plate portion fixed so as to cover the bottom housing 1A. (Top cabinet) 1B. A PC board for controlling a disk device (not shown), a flexible cable connected to the PC board, a solenoid, and other mechanisms are housed and held in the rear portion of the housing 1.

A slide holder is provided on each of both inside surfaces of the bottom housing 1A, and a slide 3 is slidably held on the slide holder. It is slidably held by a slide holder 4 provided on the surface. The drawer 2 has a mechanism unit 6 mounted in a drawer frame 5 via a cushion (not shown) for absorbing vibration, and a bottom portion thereof is closed by a drawer cover. A bezel plate 7 is attached to the front of the drawer frame 5. The mechanism section 6 includes a chassis 10, and a disk motor unit (not shown) is fixed to the chassis 10, and a spindle of the disk motor unit includes:
A hub 8 for holding the disk 20 and rotating the disk and a turntable 9 are attached. Further, a rectangular hole 13 is formed in the chassis 10 over a range in which the pickup head 12 moves, so that an objective lens 14 and the like of the pickup head 12 are exposed, and the pickup head 12 is attached to the chassis 10. And is slidably held on a pickup shaft (not shown). The chassis 10 is further provided with a feed motor and a gear mechanism (neither is shown) for moving the pickup head 12, and the pickup head 12, the disk motor unit, the feed motor and the like are connected to a PC board. Connected to a flexible cable.

As shown by a dotted line 16 in FIG. 1, a circular hole 16 is formed in a region facing the turntable 9 in the top plate 1B, and a product name or the like is provided on an upper surface of the top plate 1B. The described label 17 is affixed and the circular hole 16 is closed.

Further, in order to reduce noise generated when air is separated from the upper surface of the optical disk 20 when the optical disk 20 is rotated, the inner surface of the top plate 1B is provided with a large number in the radial direction as shown in FIG. Is formed in a spiral shape. FIG. 2 is a plan view of the lower surface of the top plate 1B as viewed from the disk 22 side.
As shown by a broken line 24, it is rotated clockwise. In general, as the disk 20 rotates, the air layer on the disk is pulled on the disk 20 due to its viscosity, and an air flow is generated on the top plate 1B as shown by the arrow 24. In the embodiment shown in FIG. 2, the number of crescent-shaped recesses 22 is
7 is preferably formed so as to extend in an arc shape in the opposite direction (counterclockwise) so as to create a turbulence in the air flow, so that the air layer on the disk 20 is smoothly separated. Even if a large number of crescent-shaped concave portions 22 are formed so as to extend in the direction in which the air flows, turbulence can be produced in the air flow. Has been confirmed to be more preferable.

The area where the many crescent-shaped recesses 22 are formed is the area 2 where the disk 20 indicated by the broken line is opposed.
5 are arranged so that most of them enter, and a number of crescent-shaped recesses 22 are arranged rotationally symmetrically with respect to the center. The crescent-shaped concave portion 22 may be directly formed with a depression (unevenness) 22 in the top plate portion 1B, or as shown in FIG. 3, a sound absorbing sheet having a depression (unevenness) 22 on the back surface of the top plate portion 1B. 26 may be directly attached, or a notch is formed in the top plate portion 1B to form a crescent-shaped hole, and a label 17 is attached to the top surface of the top plate portion 1B so as to cover the crescent-shaped notch hole. Is also good. Here, the depressions (irregularities) 22 are not limited to the case where they are formed on the sound absorbing sheet 26 itself.
A large number of through holes are formed in the sound absorbing sheet 26, and the sound absorbing sheet is attached to the back surface of the top plate 1B, so that the depressions (irregularities) 22 may be provided on the top plate 1B. Preferably, the sound absorbing sheet 26 is made of a material suitable for optimally and effectively reducing the noise in accordance with the frequency of the noise generated from the disk, which varies according to the rotation speed of the disk drive. Specifically, the sound absorbing sheet 26 may be made of PET or the like having a smooth surface, or may be a nonwoven fabric or the like having a rough surface. Further, it may be felt, rubber, or polon, and in some cases, metal or resin.

The crescent-shaped concave portion 22 may be a concave portion or a convex portion itself, or may be formed so that a large number of concave and convex portions are gathered to form a crescent-shaped pattern.

According to the inventor's consideration, this depression (unevenness)
The pattern 22 is provided in the peripheral portion in the region 25 facing the disk, rather than in the central region of the top plate portion 1B, so that noise can be effectively reduced. The reason is,
When the disk 20 is rotated at a certain number of rotations, the rotation speed (linear velocity) is higher at the periphery than at the center region,
This is because the flow velocity of the air flow generated on the disk 20 in accordance therewith is higher in the vicinity thereof, and the noise when the air flow is separated from the disk 20 is larger. For this reason, it is preferable that the depression (concavo-convex) pattern 22 is arranged in a specific area as shown by broken lines 25 and 28, for example, an area having a radius of 7 mm or more from the center point P corresponding to the rotation center of the disk 20. More practically, a radius of 16
If most of the concave (concavo-convex) pattern 22 is arranged within the range of not less than mm and not more than 60 mm, noise can be surely reduced.

Experimentally, the noise is single speed, that is, 1
It has been confirmed that the user does not care much at a rotation speed of less than 0 times speed (2200 rpm), and a large noise is generated at a rotation speed of 10 times speed or more, particularly 20 times speed or more. Therefore, it is more practical to provide the recess (irregularity) pattern 22 in a disk device in which the disk 20 is rotated at a rotation speed of 10 times or more, preferably 20 times or more.

Further, the noise is generated by the top plate 1B and the disk 20.
This is more effective when applied to a thinner disk drive in which the space between the top plate portion 1B and the disk 20 is small because of the separation sound of the air flow between The distance T0 between the top of the pattern 22 and the disk 20 is in the range of 0.5 to 1.5 mm, and more preferably, the distance T0 is in the range of 0.7 to 1.2 mm. In addition, the bottom surface in the concave portion of the concave (irregular) pattern 22 (in the case where this concave portion is formed by making a hole in the sheet 26, the back surface of the top plate portion corresponds to the bottom surface) and the front surface of the disk 20 The larger the interval Tm is, the better, but a sufficient effect is obtained when the sheet 26 having a thickness of 0.35 mm or more (preferably 0.35 mm or more and less than 1.5 mm) is attached. Therefore, it is sufficient to set the distance in the range of (T0 + 0.35 or more) mm. In a more specific example in which the sheet 26 having a thickness of 1.0 to 1.5 mm is adhered, the same applies. (T0 + 1.0-1.
5) It may be set within the range of mm.

As described above, in the structure in which the notch hole is formed in the top plate portion 1B and a label or the like is attached to the upper surface of the top plate portion 1B, the depth of the recess (unevenness) 22 is Part 1B
T0 is the distance from the back surface of the top plate 1B to the front surface of the disk 20. In such a structure, a preferable range can be similarly set by applying the thickness of the top plate 1B to the above-described preferable range of the interval Tm instead of the thickness of the sheet.

As described above, the concave (uneven) pattern 2
2, it has been confirmed that noise can be reduced, but it has also been confirmed that the following effects can be obtained. In the case where the recess (irregularity) pattern 22 is not provided and the inner surface of the top plate 1B is a flat surface, the disk 2
With the rotation of 0, an air flow is generated as described above and flows out of the outer peripheral area of the disk 20 to the outside as shown by an arrow 30 in FIG. 3, but when the velocity of the air flow is high, When a negative pressure is generated on the outer peripheral area of the disk 20 and the outer peripheral area is sucked toward the top plate 1B, the disk 20 floats when the holding force of the disk 20 is weak,
Alternatively, the disk 20 may warp even if the disk 20 is securely held. The disk warps,
In the case of floating, the power consumption of the servo system such as the focus servo increases, the vibration during rotation of the disk increases, and the data reading error increases. However, in the case where the concave (irregular) pattern 22 is provided as in the above-described embodiment,
No negative pressure is generated on the outer peripheral area of the disk 20,
In some cases, a positive pressure is generated to chuck the disk itself, thereby preventing the disk from warping or floating.

Further, when the recess (irregularity) pattern 22 is not provided and the inner surface of the top plate 1B is a flat surface,
As described above, with the rotation of the disk 20, an air flow is generated and flows out from the outer peripheral area of the disk 20 to the outside as shown by an arrow 30 in FIG. An air flow flows between the top plate 1B and the disk 20. With the inflow of the air, dust may be introduced from outside. However, the provision of the concave (irregular) pattern 22 reduces the amount of air that flows in from the outside, and reduces the inflow of dust. As a result, the possibility that an error occurs in reading data by the pickup head is reduced, and deterioration of components due to dust is prevented.

In the embodiment shown in FIG. 2, a crescent-shaped uneven pattern 22 is employed. However, as shown in FIG. A simple track-shaped uneven pattern 29 may be employed, and a half-crescent-shaped uneven pattern 31 may be employed as shown in FIG. Also, in FIG. 4A, the track-shaped uneven pattern 29 is spirally arranged in a counterclockwise direction, but as shown in FIG. 4C, the track-shaped uneven pattern 29 is clockwise. They may be arranged in a spiral. Similarly, in FIG. 2, the crescent-shaped irregular pattern 22 is spirally arranged in a counterclockwise direction, but as shown in FIG. 4D, the crescent-shaped irregular pattern 22 is spirally arranged in a clockwise direction. May be arranged.

4A to 4D, reference numeral 50 denotes
Indicates the rotation direction of the disk 20 as viewed from the optical pickup 12 side. When the disk 20 is rotated in this direction, an air flow is generated on the top plate 1B in a direction opposite to the direction of rotation of the disk 20.

The above-mentioned uneven pattern is not limited to the crescent-shaped pattern 22 or the track-shaped pattern, but various patterns can be adopted. For example, FIG.
As shown in FIG. 5A, the pattern 32 may be a curved arcuate concave-convex pattern 32 extending in the radial direction and arranged substantially symmetrically with respect to a point, or as shown in FIG. ) May be formed on the top plate portion 1B or formed on a sheet, and the sheet may be attached to the top plate portion 1B. Also, a trapezoidal pattern 33 may be arranged around the center of the top plate 1B as shown in FIG. 5C, and as shown in FIG. 5D, the trapezoidal pattern shown in FIG. May be provided on the top plate 1B.

As shown in FIG. 6A, a large number of curved strip-shaped uneven patterns 34 may be arranged concentrically, as shown in FIG. 6B. A part of the large number of band-shaped uneven patterns 34 may be provided on the top plate 1B. In addition, as shown in FIG. 6C, a number of rectangular or trapezoidal patterns extending linearly in the oblique direction of the top panel 1B may be provided on the top panel 1B. As shown in d), a large number of rectangular or trapezoidal patterns that extend linearly substantially parallel to any side of the top plate 1B may be provided on the top plate 1B.

Further, as shown in FIG. 7A, a large number of continuous grooves or continuous protrusions arranged concentrically may be provided in the top plate 1B, or as shown in FIG. 7B. A large number of rectangular uneven patterns may be provided on the top plate 1B substantially parallel to any side of the top plate 1B. Also,
As shown in FIG. 7 (c), a large number of circular concavo-convex patterns may be provided on the top plate 1B, and as shown in FIG. 7 (d), various shapes, in the illustrated example, triangular, square, Circular and track-shaped uneven patterns may be randomly provided on the top plate 1B. Further, as shown in FIG. 8 (a), a large number of circular patterns having different sizes may be provided on the top plate 1B at random, or a concave or convex pattern which is moistened in FIG. 8 (b). A pattern, for example, a circular pattern may be connected to each other by a concave portion or a convex portion.
As shown in FIG. 8, one pattern may be spirally extended, or as shown in FIG. 8D, only one arbitrary pattern may be provided on the top plate 1B.

Further, as shown in FIG. 9 (a), a large number of rectangular concave or convex patterns may be arranged in the radial direction, and the pattern shape may be changed to a rectangular shape as shown in FIG. 9 (b). May be a triangular pattern.

[0030]

As described above, according to the present invention, since the uneven pattern is provided on the inner surface of the top plate portion of the disk device, it is possible to reduce the wind noise generated by the rotation of the disk. it can. Also, it is provided on the inner surface of the top plate that the disk is deformed or floated by an air flow generated between the inner surface of the top plate and the disk when the disk rotates as the rotation speed of the disk increases. It can also be prevented by an uneven pattern.

[Brief description of the drawings]

FIG. 1 is a perspective view of an optical disk device, that is, a disk drive according to an embodiment of the present invention, schematically showing a state where a drawer is pulled out from a housing (cabinet).

FIG. 2 is a plan view schematically showing an inner surface of a top plate portion of the housing shown in FIG. 1 in the optical disc device according to one embodiment of the present invention.

FIG. 3 is a cross-sectional view schematically showing a relationship between an optical disk and a top plate in the housing shown in FIG.

4 (a) to 4 (d) are schematic plan views showing modified examples of the concavo-convex pattern provided on the inner surface of the top plate shown in FIG.

5 (a) to 5 (d) are schematic plan views showing other examples of the concavo-convex pattern provided on the inner surface of the top plate shown in FIG.

FIGS. 6A to 6D are schematic plan views showing other examples of the concavo-convex pattern provided on the inner surface of the top plate shown in FIG.

FIGS. 7A to 7D are schematic plan views showing other examples of the concavo-convex pattern provided on the inner surface of the top plate shown in FIG.

FIGS. 8A to 8D are schematic plan views showing other examples of the concavo-convex pattern provided on the inner surface of the top plate shown in FIG.

FIGS. 9A and 9B are schematic plan views showing another example of the concavo-convex pattern provided on the inner surface of the top plate shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Housing 2 ... Drawer 1B ... Top plate 20 ... Disk 22 ... Concavo-convex pattern 26 ... Sound absorbing sheet

Claims (3)

[Claims] 1. A housing having a top plate portion, a disk rotating mechanism for rotatably holding a disk in the housing, and a mounting mechanism for loading a disk in the housing and removing the disk from the housing. An optical disk apparatus comprising: an optical disk drive, wherein a pattern of projections and depressions is formed in a region of an inner surface of a top plate portion facing the disk when the disk is loaded. 2. A housing having a top plate, a disk rotating mechanism for rotatably holding a disk in the housing, and a mounting mechanism for loading a disk in the housing and taking out the disk from the housing. In the optical disk drive provided with the disk, when the disk is loaded, an uneven pattern is formed in the area of the inner surface of the top plate facing the disk, and the pattern is formed in a direction opposite to the direction of the air flow generated on the disk surface. An optical disc device comprising a number of extended patterns arranged in a rotating direction. 3. The optical disk device according to claim 2, wherein the uneven pattern is provided on a sheet attached to the inner surface of the top plate portion, and the sheet is made of a material having a sound absorbing effect.