JPH07114761A - Disk clamping mechanism for optical disk device - Google Patents

Abstract

PURPOSE:To always obtain enough clamping force in a disk clamping mechanism for clamping a thick disk and a thin disk. CONSTITUTION:The state as shown in the figure is a state of clamping the thick disk, where a magnet 16 is not in contact with a protrusion 4a of a disk guide member 4 and a metal plate 6. In this case, when attracting force of the magnet 16 is denoted as M, while assuming weight of the optical disk 8 W and elastic force of a compression coil spring 5 F5, the clamping force is M+W-F5. In the case of clamping the thin optical disk, a clamp member 13 is further lowered from the state as shown in the figure so that the magnet 16 is brought into close contact with a metal plate 6. The magnet 16 is brought into contact with the protrusion 4a of the disk guide member 4 to push upward the disk guide member 4. The clamp member 13 is separated from a clamp member holding part 9, and elastic force F14 of a compression coil spring 14 is applied to the optical disk. In this case, the clamping force is F14+W.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc clamp mechanism for an optical disc device, and more particularly to a disc clamp mechanism for clamping two types of thick and thin discs.

[0002]

2. Description of the Related Art In a conventional disc clamp mechanism for clamping an optical disc by adsorbing a magnet provided on a clamper to a magnetic metal plate provided on a turntable, a magnet provided on a clamp member holding portion of the clamper is attached to a turntable. The clamp member holding part is fixed by adsorbing it to the provided metal plate, and the disc guide member biased upward by the spring with respect to the turntable fits into the center hole of the disc to position the disc and hold the clamp member. The disc is pressed against the turntable by the clamp member against the pressure of the disc guide member by the elastic force of the spring arranged between the portion and the clamp member.

[0003]

In the above-mentioned conventional disc clamp mechanism, when a thin disc is clamped, the spring disposed between the clamp member holding portion and the clamp member is stretched so that its elasticity becomes small and the disc is thick. There is a drawback in that the clamping force when clamping a thin disc is considerably smaller than when clamping a disc.

The present invention has been made in view of the above points, and an object of the present invention is to provide a disc clamp mechanism which can obtain a sufficient clamping force even when a thin disc is clamped. .

[0005]

DISCLOSURE OF THE INVENTION A disc clamp mechanism of an optical disc apparatus according to the present invention includes a turntable fixed to a spindle motor, a disc guide member biased upward by a spring with respect to the turntable, and a turntable. The member to be attracted is provided, and a clamper that moves up and down above the turntable, the clamper pressing the disk to the turntable, a clamp member holding portion for holding the clamp member vertically movable, In a disk clamp mechanism configured by a spring arranged between the clamp member holding portion and the clamp member to urge the clamp member downward, and a suction member provided in the clamp member holding portion for sucking the sucked member, When clamping a thick disc, the disc guide member engages with the disc center hole. Press upwardly disk Te, suction force of the clamp member and the clamp member holding portion and is in close contact suction member and the suction member and approaches suction member is applied to the disk,
When a thin disc is clamped, the suction member descends until it abuts on the member to be attracted, so that the disc guide member is pushed down to separate from the disc, and the clamp member separates from the clamp member holding portion. Is configured to join the disk.

[0006]

According to the disc clamp mechanism of the optical disc apparatus of the present invention, when a thick disc is clamped, the suction force of the suction member is applied as a force for pushing the disc downward from the clamp member to urge the disc guide member upward. The elasticity of the spring acts as a force to push the disc upward. Therefore, the force with which the disc is pressed against the turntable, that is, the clamping force, is the sum of the suction force of the suction member and the gravity of the disc minus the elastic force of the spring.

Further, when a thin disc is clamped, the disc guide member is separated from the disc, and only the elastic force of the spring for urging the clamp member is applied to the disc. Therefore, the clamping force is the sum of the elastic force of the spring and the gravity of the disc. Become.

By setting the suction force of the suction member, the spring force of the spring for urging the disc guide member and the spring force of the spring for urging the clamp member to appropriate values, a clamping force for clamping a thick disc and a thin disc can be obtained. Each of the clamping forces at the time of clamping can be set to the optimum value.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A disk clamp mechanism of an optical disk device according to an embodiment of the present invention will be described based on the drawings. FIG. 1 is a sectional view showing a disc clamp mechanism of an optical disc device according to an embodiment of the present invention. In the figure, 1 is a rotary shaft of a spindle motor. A turntable 3 is fixed to the rotary shaft 1 via a boss 2.

Reference numeral 6 denotes a ring-shaped magnetic metal plate,
It is fastened to the turntable 3 by screws 7. Three screws 7 are fastened to the thick ribs of the turntable 3 at equal intervals.

The disc guide member 4 is loosely fitted to the rotary shaft 1 and is biased upward by a compression coil spring 5. Ribs that connect the inner peripheral portion and the outer peripheral portion of the disc guide member 4 are provided at three locations at equal intervals and lie under the metal plate 6. That is, the metal plate 6 regulates the upper position of the disc guide member 4. Disc guide member 4
The outer peripheral part of is narrowed upward so as to guide the optical disk 8. Protrusions 4 a having a height higher than the thickness of the metal plate 6 are provided on three ribs of the disc guide member 4.

The part held by the clamper lifting member 20 is the clamper. The clamp member holding portion 9 is fitted and integrated with the guide member 10. An upper plate 11 is fastened to the clamp member holding portion 9 with three screws 12. A ball 15 that is pressed by the clamper elevating member 20 is press-fitted in the upper portion of the guide member 10.

The clamp member 13 is a clamp member holding portion 9
Is held by the three compression coil springs 14 so as to be vertically movable. The three claws 13a provided on the clamp member 13 are locked to the clamp member holding portion 9 to regulate the downward position of the clamp member 13.

The ring-shaped magnet 16 is bonded to the yoke 17. The yoke 17 is locked to the clamp member holding portion 9 by three stepped screws 19. The compression coil spring 18 biases the yoke 17 downward.

Next, the operation of the disc clamp mechanism having the above structure will be described. The optical disk 8 is placed on the disk guide member 4 by the loading mechanism as shown in FIG. The elasticity of the compression coil spring 5 is larger than the weight of a large-diameter thick disk (for example, a 30 cm LD disk), and the disk guide member 4 supports the optical disk 8 at the upper limit position regulated by the metal plate 6.

From the state shown in FIG.
0 begins to fall. The clamper is the clamper lifting member 2
The clamp member 13 comes into contact with the optical disk 8 as shown in FIG.

The clamper elevating member 20 further descends from the state shown in FIG. 2, and the clamper elevating member 20 pushes the ball 15 as shown in FIG. The clamp member holding portion 9 descends, and the elastic force F ₁₄ of the compression coil spring 14 is applied to the optical disk 8 from the clamp member 13.

The elastic force F ₁₄ increases as the clamper elevating member 20 descends. The elasticity of the compression coil 5 spring is F
₅ and the gravity of the optical disk 8 is W, F ₁₄ > F ₅ -W
From the point when
With it, it descends and comes into contact with the turntable 3.

The clamper lifting member 20 is further lowered,
When the magnet 16 approaches the metal plate 6 and its attractive force becomes larger than the elastic force of the compression coil spring 14, the clamper descends without being pushed by the clamper elevating / lowering member 20,
As shown in FIG. 4, the clamp member 13 comes into close contact with the clamp member holding portion 9.

After that, the clamper elevating / lowering member 20 rises to the clamped state shown in FIG. The state shown in FIG. 5 shows a state in which a thick disc is clamped, and the magnet 16 includes the protrusion 4 a of the disc guide member 4 and the metal plate 6.
Is not in contact with. When the attraction force of the magnet 16 is M, the clamping force at this time is M + WF- ₅ .

When a thin optical disk is clamped, the clamp member 13 is further lowered and the magnet 16 is moved to the metal plate 6 so that the state shown in FIG. 5 changes to the state shown in FIG.
Stick to. The magnet 16 comes into contact with the protrusion 4a of the disc guide member 4 to push down the disc guide member 4. The disc guide member 4 is separated from the thin optical disc 8a.

The clamp member 13 is separated from the clamp member holding portion 9, and the elastic force F ₁₄ of the compression coil spring 14 is applied to the thin optical disk 8a. The clamping force at this time is F ₁₄ + W.

The elasticity F ₁₄ of the compression coil spring 14, by appropriately selecting the suction force M elasticity F ₅ and the magnet of the compression coil spring 5, when clamping the clamping force and a thin disk when clamping thick disk Each of the clamping forces of can be set to the optimum value.

[0024]

According to the disc clamping mechanism of the optical disc apparatus of the present invention, the clamping force for clamping a thick disc and the clamping force for clamping a thin disc can be optimized.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a disc clamp mechanism of an optical disc device according to an embodiment of the present invention.

FIG. 2 is a sectional view showing an operating state of the disc clamp mechanism.

FIG. 3 is a cross-sectional view showing another operating state of the disc clamp mechanism.

FIG. 4 is a cross-sectional view showing still another operating state of the disc clamp mechanism.

FIG. 5 is a cross-sectional view showing still another operation state of the disc clamp mechanism.

FIG. 6 is a cross-sectional view showing still another operating state of the disc clamp mechanism.

[Explanation of symbols]

 1 Spindle Motor Rotation Shaft 2 Boss 3 Turntable 4 Disc Guide Member, 4a Protrusion 5 Compression Coil Spring 6 Metal Plate 7 Screw 8 Optical Disc 9 Clamp Member Holding Part 10 Guide Member 11 Upper Plate 12 Screw 13 Clamp Member, 13a Claw 14 Compression Coil Spring 15 Ball 16 Magnet 17 Yoke 18 Compression coil spring 19 Stepped screw 20 Clamper lifting member

Claims (1)

[Claims] 1. A turntable fixed to a spindle motor, a disc guide member biased upward by a spring with respect to the turntable, a member to be attracted provided on the turntable, and lifted and lowered above the turntable. A clamp member for pressing the disk to the turntable, a clamp member holding portion for holding the clamp member in a vertically movable manner, and a clamp member arranged between the clamp member holding portion and the clamp member. In a disc clamping mechanism of an optical disc device including a spring that urges the disc downward and a suction member that is provided in the clamp member holding portion and that sucks the suctioned member, when the thick disc is clamped, the disc guide member is used. Fit the center hole and push the disk upward, When the thin member is clamped, the suction member and the suction member come close to each other, the suction force of the suction member and the suction member come close to each other, and when the thin disk is clamped, the suction member descends until it contacts the suction member. A disk clamp mechanism configured such that the member is pushed down to separate from the disk, the clamp member separates from the clamp member holding portion, and the elastic force of a spring for urging the clamp member is applied to the disk.