JPH03273556A - Disk clamping device - Google Patents

Abstract

PURPOSE:To approximate the force for pinching disks to the attraction force of a magnet as for as possible and to shorten the time for rising of the revolution of a spindle motor by providing a 2nd energizing means which energizes a clamper cooperatively with a 1st energizing means when the clamper pinches the thick disk. CONSTITUTION:The 1st energizing means 13 for energizing the clamper 12 when the clamper pinches the thin disk 7 and the 2nd energizing means 15 for energizing the clamper 12 cooperatively with the 1st energizing means 13 when the clamper pinches the thick disk 1 are provided. Namely, the magnet 9 attracts to a attraction cup 3 and the clamper 12 is actuated by the energizing force of a thin disk pressing spring 15 to pinch the thick disk 1. Further, the spring force of the thick disk pressing spring 15 is transmitted from a stopper ring 17 to the clamper 12 to pinch the thick disk 1. The pinching force on the thick disk 1 of this time is set slightly lower than the attraction force of the magnet so that the force to pinch the disk is approximated to the attraction force of the magnet as far as possible. The time for the rising of the revolution of the spindle motor 6 is shortened in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a disc clamping device for clamping an optical video disc between a turntable of a video disc player and clamping the disc.

2. Description of the Related Art In recent years, video disc players for playing optical video discs have become popular. Optical video discs are currently available in discs with an outer diameter of 30 cm and a thickness of 2.5 mm, discs with an outer diameter of 20 cm and a thickness of 2.5 mm (for double-sided playback), and 1.2
There are three types: 5mm (for single-sided playback). below,
A conventional disc clamping device for a video disc player that plays these discs will be described.

In the following description, a disk with a thickness of 2.5 mm will be referred to as a thick disk, and a disk with a thickness of 1.25 mm will be referred to as a thin disk.

FIG. 3 is a sectional view of a conventional disc clamping device showing a state in which a disc is clamped.

In FIG. 3, 1 is a thick disk, and 7 (indicated by a two-dot chain line) is a thin disk, which are placed on the turntable 2 (one of them is placed on the turntable 2 during playback). A magnetic suction cup 3 is fixed to the turntable 2. The centering ring 4 is held on the spindle motor shaft 5 with a tapered surface 4a formed on the outer periphery. The spindle motor 6 rotates together with the turntable 2 and the spindle motor shaft 5. The flange 30 has a positioning hole 30a in the center. magnet 3
1 is fixed to the yoke plate 32.

The yoke plate 32 is attached to the flange 30 with attachment screws 33. The clamper 34 is held by the flange 30 so as to be slidable in the axial direction, and a compression spring 35 is disposed between the clamper 34 and the flange 30. The transfer plate 36 holds the outer circumference 34a of the clamper 34 and moves in the directions of arrows A and B, but in the clamped state it is separated from the clamper 34 as shown in FIG. (The illustration of the drive mechanism of the plate 34 is omitted)
.

The operation of the disk clamp device configured as described above will be explained below.

First, a state in which a thick disk having a thickness of 2.5 mm is clamped will be explained. As shown in FIG. 3, a thick disk drive (indicated by a solid line) is placed on the turntable 2, and its inner diameter abuts against the tapered surface 4a of the centering ring 4, and is positioned coaxially with the spindle motor shaft 5. . Also, flange 3
0 as well, the positioning hole 30a engages with the spindle motor shaft 5 and is positioned coaxially. In this state, the magnet 31 is attracted to the suction cup 3, so the clamper 34 (indicated by a solid line) presses the thick disk 1 with the biasing force of the compression spring 35. The urging force of the compression spring 35 at this time is the force F2 shown in FIG. In this clamped state, the spindle motor 6 rotates, and a pickup (not shown) reads and reproduces signals recorded on the thick disk 1.

Next, a state in which a thin disk having a thickness of 1.25 mm is clamped will be explained. As shown in FIG. 3, a thin disk 7 (indicated by a two-dot chain line) is placed on the turntable 2, and its inner diameter is in contact with the tapered surface 4a of the centering ring 4, and is coaxial with the spindle motor shaft 5. Positioned. Also, flange 30 is also ranked 11! A fixed hole 30a engages with and is positioned coaxially with the spindle motor shaft 5. In this state, since the magnet 31 is attracted to the suction cup 32, the clamper 34 (indicated by the two-dot chain line) presses the thin disk 7 with the biasing force of the compression spring 35. The biasing force of the compression spring 35 at this time is the force Fl shown in FIG. In this clamped state, the spindle motor 6 rotates, and a pickup (not shown) reads and reproduces signals recorded on the thin disk 7. After the reproduction is completed, the transfer plate 36 is moved in the direction of arrow B (the driving mechanism is not explained) to release the clamp.

Problems to be Solved by the Invention However, in the conventional configuration described above, the force of the compression spring must be set smaller than the attraction force of the magnet, as shown in FIG. In this case, as the magnet approaches the suction cup 3, the difference between the attraction force of the magnet and the biasing force of the compression spring 35 gradually increases. When the magnet is attracted to the suction cup, a difference F between the attraction force of the magnet and the spring force shown in FIG. 4 occurs. In the conventional configuration, this difference in F becomes large, and the disk clamping force becomes small.

If this clamping force is small, the disc will slip,
There is a problem in that the rotation startup time of the spindle motor must be slowed down. This problem can be solved by increasing the attraction force of the magnet and increasing the force of the compression spring 35, but in this case, new problems arise such as an increase in the clamp release force and a loud noise during attachment and detachment.

In view of the above-mentioned conventional problems, the present invention is a disk clamping device that increases the disk clamping force by minimizing the difference F between the magnetic attraction force and the spring force, thereby speeding up the spindle motor rotation startup time. The purpose is to provide

Means for Solving the Problems In order to achieve this object, the disk clamping device of the present invention includes a first urging means for applying force when the clamper clamps a thin disk, and a first urging means for applying force when the clamper clamps a thick disk. The structure includes second urging means for urging in cooperation with the first urging means when clamping.

Operation By having the above configuration, the disk clamping device of the present invention allows the thick disk to be moved between the first urging means and the second urging means.
By cooperating with the urging means to increase the clamping force, it is possible to speed up the rotation start-up time of the spindle motor.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing a state in which a thin disk is clamped by a disk clamping device according to an embodiment of the present invention, and FIG.
The figure is a sectional view showing a state in which a thick disk is clamped.

In FIG. 1, a thin disc 7 is placed on a turntable 2. As shown in FIG. A magnetic suction cup 3 is fixed to the turntable 2. The centering ring 4 has a tapered surface 4 on the outer periphery.
a and is held on the spindle motor shaft 5.

The spindle motor 6 rotates together with the turntable 2 and the spindle motor shaft 5. Flange 8
has a positioning hole 8a in the center. magnet 9
is fixed to the yoke plate 10. The yoke plate 10 is attached to the flange 8 with attachment screws 11. 12
is held by a clamper on the flange 8 so as to be slidable in the axial direction. A thin disk pressing spring 13 is disposed between the clamper 12 and the flange 8, and a shaft 1 is attached to the flange 8.
6 is slidably provided. A retaining ring 17 is attached to the shaft 16.
is attached, and a thick disk pressing spring 15 is provided between the retaining ring 17 and the flange 8. The transfer plate 14 holds the outer circumferential portion 12a of the clamper 12 and moves in the directions of arrows A and B, but in the clamped state, it moves in the direction A and is separated from the clamper 12 as shown in FIG. Yes (the diagram of the drive mechanism of this transfer plate 14 is omitted)
.

In FIG. 2, the thick disk 1 is placed on the turntable 2 surface. Hereinafter, since the other configurations are the same as the configuration shown in FIG. 1 above, description of the configuration will be omitted.

The operation of the disk clamp device configured as described above will be explained below.

First, a state in which a thin disk with a thickness of 1.25 mm is clamped will be explained. As shown in FIG. 1, the thin disk 7 is placed on the turntable 2, and the inner diameter portion is in contact with the tapered surface 4a of the centering ring 4, and the spindle motor shaft 5
is positioned coaxially with the

Also, the positioning hole 8a of the flange is connected to the spindle motor shaft 5.
and are positioned coaxially. In this state, the magnet 9 is attracted to the suction cup 3, so the clamper 12 clamps the thin disk 7 with the biasing force of the thin disk pressing spring 13. The clamping force to this thin disk is the force Fl as shown in FIG. In this clamped state, the spindle motor 6 rotates, and a pickup (not shown) reads and reproduces signals recorded on the thin disk 7.

Next, a state in which a thick disk having a thickness of 2.5 mm is clamped will be explained. As shown in FIG. 2, the thick disk 1 is placed on the turntable 2, with its inner diameter abutting the tapered surface 4a of the centering ring 4, and positioned coaxially with the spindle motor shaft 5.

Further, the positioning hole 8a of the flange 8 is engaged with the spindle motor shaft 5, and the flange 8 is positioned coaxially with the spindle motor shaft 5. At this time, the magnet 9 is attracted to the suction cup 3. In this clamped state, the clamper 1 is
2 clamps the thick disc 1, and furthermore, the spring force of the thick disc pressing spring 15 is transmitted from the retaining ring 17 to the clamper 12 to clamp the thick disc 1. In other words, the clamping force on the thick disk 1 includes the biasing forces of both the thin disk pressing spring 13 and the thick disk pressing spring. The clamping force on the thick disk 1 at this time is a force F3 as shown in FIG. 4, which is set slightly lower than the attraction force F4 of the magnet. Therefore, the magnet 9 is reliably attracted to the suction cup. With the thick disk 1 clamped, the spindle motor 6 rotates, and a pickup (not shown) reads and reproduces signals recorded on the thick disk 1. After the reproduction is completed, the transfer plate 12 is moved in the direction of arrow B (the drive mechanism is not shown) to release the clamp (the state after the clamp is released is not shown).

As described above, according to this embodiment, by pressing the thick disk with the thin disk pressing spring and the thick disk pressing spring, it is possible to make the disk clamping force as close as possible to the attraction force of the magnet.

Effects of the Invention As described above, the disk clamping device of the present invention has a first structure for applying force when the clamper clamps a thin disk.
The clamping force of the disk can be maximized by having the biasing means and the second biasing means for biasing in cooperation with the first biasing means when the clamper clamps a thick disk. It can approach the adsorption power of a magnet. Therefore, it is possible to speed up the spindle motor's rotation start-up time, which has a great practical effect.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a state in which a thin disk is clamped by a disk clamping device according to an embodiment of the present invention, and FIG.
The figure is a cross-sectional view showing a state in which a thick disk is clamped, Figure 3 is a cross-sectional view showing a state in which a disk is clamped by a conventional disk clamp device, and Figure 4 is a cross-sectional view showing a state in which a disk is clamped with a conventional disk clamp device. Figure 4 shows the distance between the magnet and the suction cup, the magnetic attraction force, and the spring. FIG. 3 is a characteristic diagram showing a force relationship. 2...Turntable, 7...Thin disc,
8...Flange, 9...Magnet, 12
... Clamper, 13... Thin disk pressing spring, 14... Transfer plate.

Claims (1)

[Claims] (1) A turntable that is rotationally driven by a motor and on which a disk is placed; a clamper that clamps the disk on the turntable surface; a flange provided on the clamper so as to be slidable in the axial direction; and a flange provided on the flange. a magnet that attracts the turntable surface; a transfer means for attaching and detaching the clamper to and from the disk; a first urging means for urging the clamper when clamping the thin disk; When the clamper clamps the thick disk, the first
1. A disk clamping device comprising: a second biasing means for biasing in cooperation with the biasing means.