JP2000215570A - Disk-holding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable thinning a device and reducing cost by providing a ring member, which is attached to the circumference of a cylindrical press-fitting part and generates stress for compressing the press-fit part at the side of a shaft. SOLUTION: A metallic ring 22 is press-fitted in the outer periphery of a hub 21 in a resin-molded turn table 15. The ring 22 is press-fitted to the hub 21 due to with tensile stress generated in a circumference direction by the shaft 13 of a spindle motor 12 which is press-fitted to the hub 21 of the resin- molded turn table 15 by the ring 22. At the same time, compression stress in the radial direction is generated in the hub 21, tensile stress in the circumferential direction, which is generated in the hub 21, is reduced and, then the press- fitting strength in the shaft 13 and the turn table 15 can be kept, even if the height of the hub 21 of the resin-molded turn table 15 is low as indicated by the arrow h2. Therefore, sufficient press-fitting strength is obtained, in spite of the shallow fitting depth in the shaft 13 and the hub 21 and the device is made thin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk holding device for supporting a disk, such as an optical disk such as a CD-ROM, mounted on the disk turntable so as to be rotatable integrally with the disk turntable. The present invention relates to an improvement in the holding mechanism of the above.

[0002]

2. Description of the Related Art Conventionally, as one of disk clamping methods for portable CD players and CD-ROM drives for notebook computers, there is a self-holding clamping method using a plurality of balls. This is so that a plurality of balls are biased and arranged at the center of the turntable so as to protrude in the radial direction of the turntable, and the disc is held on the turntable by a pressing force due to the protruding balls. It was made. Hereinafter, for example, Japanese Patent Application Laid-Open No. 3-1
A conventional example of this type described in Japanese Patent No. 57859 will be specifically described.

FIGS. 3 and 4 are a plan view and a side view, respectively, showing the structure of a conventional disk holding device. In these figures, a central portion of a turntable 1 which is driven to rotate by a spindle motor has an upper part. The projecting peripheral wall 2 is integrally formed, and the cap-shaped ball holder 3 is fitted to the peripheral wall 2, thereby fixing the ball holder 3 to the turntable 1. The outer diameter of the ball holder 3 is equal to or slightly smaller than the diameter of the center hole of the disk 4. The ball holder 3 has groove-shaped ball guides 5 extending in the radial direction therein at three locations at equal intervals in the circumferential direction. A ball 6 is movably arranged. In addition, each ball guide 5 has an opening that is open on the outer peripheral surface of the ball holder 3,
Further, each ball 6 is urged radially outward by a coil spring 7 arranged in each ball guide 5.

The side walls 8 near the opening of each ball guide 5 protrude inward to prevent each ball 6 from falling off. Each of the balls 6 is urged by a coil spring 7 so that a part thereof projects from the opening of the ball holder 3. Between the projecting position of the ball 6 and the disk receiving surface of the turntable 1,
An appropriate dimension determined from the thickness dimension of the disk 4 is secured. Reference numeral 12 denotes a spindle motor,
Reference numeral 13 denotes a shaft serving as a rotation axis.

Next, the disc mounting operation will be described.
When mounting the disc 4 on the turntable 1,
As shown by a two-dot chain line in FIG. 4, the center hole of the disc 4 is placed on the ball 6, the clamp area 9 of the disc 4 is pressed down by a finger, and the ball 6 is pressed against the urging force of the coil spring 7. The disc 4 is placed on the turntable 1 while moving backward. When the disc 4 is placed on the turntable 1,
A part of the ball 6 protrudes from the opening of the ball holder 3 by the urging force of the coil spring 7, and the projection force of the disc 4
The upper edge of the center hole is pressed, and the disc 4 is pressed on the turntable 1 to be able to rotate integrally with the turntable 1.

On the other hand, when removing the disk 4 from the turntable 4, as shown in FIG.
0 is forcibly lifted up the disk 4 with a finger. By doing so, the edge of the center hole of the disk 4 comes off the ball holder 3 while the ball 6 is retracted against the urging force. When the disc 4 is detached, a large force is applied to the turntable 1 in the vertical direction. Therefore, the height of the hub 11 of the turntable 1 indicated by an arrow h1 is increased, and the hub 11 of the turntable 1 and the spindle motor 12 are moved. It is necessary to strengthen the joint with the shaft 13,
An adhesive 14 is applied to the top surface of the shaft 13 of the spindle motor 12 to assure the press-fitting strength due to aging, so that the press-fitting is strengthened.

[0007]

The conventional disk holding device is configured as described above, and has a structure in which the disk is forcibly attached and detached against the urging force of the ball.
A large force is applied in the vertical direction of the turntable. Therefore, it is necessary to increase the press-fit strength between the spindle motor shaft and the turntable, and as a result,
The length of the portion indicated by the arrow h1 in FIG. 4 is required, the thickness of the turntable increases, the product cannot be made thinner, and the press-fitting strength of the turntable decreases due to aging. Has been applied, so that there was a problem that the cost could not be reduced.
SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a disk holding device capable of reducing the thickness of a product and reducing the cost.

[0008]

According to a first aspect of the present invention, there is provided a disk holding device, wherein a cylindrical press-fit portion formed at the center of a turntable on which a circular disc is mounted is press-fitted into a shaft of a spindle motor. And a ring member which is attached around the cylindrical press-fitting portion and generates a stress for compressing the cylindrical press-fitting portion toward the shaft.

According to a second aspect of the present invention, there is provided a disk holding device according to the first aspect, wherein a plurality of guides are formed radially on the surface of the turntable around the cylindrical press-fit portion. A groove, and a holder disposed in the guide groove so as to be slidable and elastically biased such that a curved end portion protrudes from an opening formed at the guide groove end. The ring member constitutes a bottom surface portion of the guide groove in which the holder is arranged.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) Hereinafter, a disk holding device according to Embodiment 1 of the present invention will be described with reference to the drawings. The disk clamp device according to the present embodiment is a mechanism for holding a disk serving as a recording medium for information signals such as an optical disk such as a so-called portable player and a CD-ROM drive for a notebook personal computer. As shown in FIG. 1, at the center of the upper surface of the resin-molded turntable 15, a cylindrical projection 16 for fitting into the center hole of the disk 4 is integrated with the resin-molded turntable 15. Is provided. The tip of the projection 16 is tapered.
The groove-shaped guides 17 extending in the radial direction are provided at three locations at equal intervals in the circumferential direction inside the projection 16, and are movable along the guide 17 in the guide 17. , A CD holder 18 is arranged. Each of the guides 17 has an opening opening on the outer peripheral surface of the projection 16, and each of the CD holders 18 is directed radially outward by a coil spring 19 arranged in each of the guides 17. Being energized. The side walls 20 near the openings of the guides 17 protrude inward, thereby preventing the CD holders 18 from protruding in the outer peripheral direction. As shown in FIG. 2, a metal ring 22 is pressed into the outer periphery of the hub 21 of the turntable 15 formed of resin.

Next, the function and effect will be described. The tensile stress generated in the circumferential direction by the shaft 13 of the spindle motor 12 pressed into the hub 21 of the resin-molded turntable 15 by the metal ring 22 causes the metal ring 22 to move. When the hub 21 is press-fitted and a radial compressive stress is generated in the hub 21, circumferential tensile stress generated in the hub 21 is reduced. As a result, the resin-molded turntable is formed. 15, the height of the hub 21 is lower than that of the conventional one as indicated by an arrow h2.
2, the press-fit strength between the shaft 13 and the resin-molded turntable 15 can be maintained, and the thickness of the resin-molded turntable 15 can be reduced, so that the product can be made thinner. is there. The metal ring 22 also serves to prevent the CD holder 18 from falling off when the disc 4 is mounted.

As described above, according to the present embodiment, the shaft 13 of the spindle motor 12 of the turntable 15
A metal ring 22 is provided around the hub 21 that fits with the hub 21, and the ring 22 applies a compressive stress in the radial direction to the hub 21. Even if it is shallow, sufficient press-fit strength can be obtained, resulting in a product that can be made thinner. In addition, there is no need to apply adhesive to the press-fit portion of the hub, which reduces the cost as before. can do.

Further, since the ring 22 constitutes the bottom surface of the guide 17 on which the holder 18 is disposed, the hub 21 and the guide 1 are attached to the turntable 15.
7, the holder 18 and the coil spring 19 for urging the holder 18 can be easily incorporated into the guide 17.

[0014]

As described above, according to the disk holding device of the first aspect of the present invention, the cylindrical press-fit portion formed at the center of the turntable on which the circular disk is mounted is connected to the spindle motor. The disk holding device press-fitted to the shaft has a ring member attached around the cylindrical press-fit portion and generating a stress for compressing the cylindrical press-fit portion toward the shaft. A sufficient press-fit strength can be obtained even if the press-fit depth of the shaft press-fit portion of the table with the shaft is shallow, and no adhesive is required to enhance the press-fit strength of the turntable shaft. Since the thickness of the table can be reduced, it is possible to obtain an effect that the thickness of the product can be reduced and the cost can be reduced.

According to a second aspect of the present invention, there is provided the disk holding device according to the first aspect, wherein the plurality of radially formed radially formed on the surface of the turntable around the cylindrical press-fit portion. A guide groove, and a holder that is slidably disposed in the guide groove, and is elastically urged such that a tip portion formed into a curved surface protrudes from an opening formed at the tip of the guide groove. Since the ring member constitutes the bottom surface of the guide groove in which the holder is arranged, the press-fit portion and the guide groove can be integrally formed on the turntable, and the guide The holder can be easily incorporated in the groove.

[Brief description of the drawings]

FIG. 1 is a cross-sectional plan view showing an example of a disk holding device according to a first embodiment of the present invention, centering on a turntable.

FIG. 2 is a front sectional view of the disk holding device.

FIG. 3 is a sectional plan view showing an example of a conventional disk holding device.

FIG. 4 is a front sectional view showing a state in which a disk is attached and detached by the conventional disk holding device.

[Explanation of symbols]

 2 Peripheral wall 3 Ball holder 4 Disk 5 Ball guide 19 Coil spring 20 Side wall 21 Turntable hub 12 Spindle motor 13 Shaft 15 Turntable 16 Turntable projection 17 Guide 18 CD holder 22 Metal ring

Claims (2)

[Claims] 1. A disk holding device in which a cylindrical press-fit portion formed at the center of a turntable on which a circular disk is mounted is press-fitted into a shaft of a spindle motor. A disk holding device, comprising: a ring member that is attached and generates a stress that compresses a cylindrical press-fit portion toward the shaft. 2. The disk holding device according to claim 1, wherein a plurality of guide grooves are formed radially on the surface of the turntable around the cylindrical press-fit portion, and each of the guide grooves is slidably movable in the guide groove. And a holder elastically urged so that a distal end formed into a curved surface protrudes from an opening formed at the distal end of the guide groove, wherein the ring member includes a guide on which the holder is disposed. A disk holding device comprising a bottom surface of a groove.