JPH067475Y2 - Disc clamp device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field of the Invention The present invention relates to a disc clamp device, and in particular, in a compact disc player, a turntable for rotating the disc is arranged so as to face the label surface of the disc, and The present invention relates to a disc clamp device having a structure in which a clamper for holding a disc is arranged in the center.

2. Description of the Related Art Many conventional compact disc players have a disc clamp device as shown in FIG.
In the figure, 1 is a turntable, 2 is a disk clamper, 3
Indicates a compact disc, and 4 indicates an optical pickup.

The turntable 1 is fixed to a spindle 6 of a motor 5, and the clamper 2 is rotatably supported by the tip of a clamp arm 7. The turntable 1 is located on the lower side of the disc 3 and the clamper 2 is located on the upper side of the disc 3.

The disc 3 is clamped by the clamper 2 on the turntable 1 with the signal recording surface 8 facing down and the label surface 9 facing up, and rotated in the direction of arrow A. The pickup 4 moves along the guide rail 10 in the direction of arrow B,
The signal recorded on the disk 3 is read.

However, in the disc clamping device as described above, the disc 3 is clamped by bringing the signal recording surface 8 into contact with the turntable 1, and the pickup 4 facing the signal recording surface 8 faces the inner peripheral portion of the disc 3. Since it moves to the position, the maximum outer diameter d ₁ of the turntable ₁ is restricted to about 30 mm. Therefore, the disk 3 is supported only by the limited narrow portion around the center hole.

On the other hand, due to its structure, the disk 3 is apt to warp and bend, and the warp amount a is actually several hundreds of microns.

Therefore, conventionally, the diameter d ₁ of the turntable ₁ is restricted, and the peripheral portion of the disk 3 cannot be locked, so that the above-mentioned warp cannot be corrected. Therefore, due to the warp and the like, particularly when reproducing the vicinity of the outer circumference, the optical axis of the laser beam of the pickup 4 and the desired track position do not face each other, and a skew error and a defocusing occur, and the reproduction characteristic is deteriorated. There was a problem that it could be adversely affected.

Therefore, in order to improve the above problems, the applicant of the present invention has previously proposed a device as shown in FIGS. 5 and 6 in Japanese Utility Model Application No. 62-68947. As shown in FIG. 5 and FIG. 6, this device uses the disc 3 mounted on the disc tray 15.
The clamper 13 is attracted to the magnets 11a and 11b provided on the turntable 11 from below, and the clamper 1
3 and the turntable 11 sandwich the disc 3, and at this time, the label surface 9 of the disc 3 is in close contact with the turntable 11, the recording surface 8 faces the optical pickup 16, and the turntable 11 is It is rotated by a motor 12 arranged above it. Further, the clamper 13 is housed below the disc tray 15 so as not to get in the way when the disc tray 15 on which the disc 3 is placed moves in the direction of arrow C ₂ . The clamper 13 is clamped by a clamp arm drive device 14 to a clamp arm 14a.
Is rotated in the direction of the arrow D ₂ to raise the disc 3 and hold it on the turntable 11. Further, when the clamp released by rotating the clamp arm 14a in the arrow D ₁ direction, lowering the clamper 13, thereby placing the disc 3 in the disc tray 15.

Note that the disk 3 is taken out, replaced, or the like by operating the disk tray 15 in the direction of arrow C ₁ by an external operation so that the disk tray 15 is projected to the outside of the apparatus.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the conventional disc clamp device having a structure in which the turntable is provided on the label surface of the disc, the disc 3 is moved upward from below the disc 3 by the disc clamper 13 to turn the turntable. 11, the center hole of the disk 3 was fitted with the convex portion provided on the turntable 11 to center the disk 3, so that the user performed an erroneous operation or received an external force. When the disc clamp mechanism 14 operates and the disc clamper 13 moves up and the disc 3 is lifted from the tray 15 without being properly attached to the disc mounting tray 15 due to an impact or the like, the center hole of the disc 3 is It does not fit with the convex part (centering member) provided in the center of the turntable 11, and the deviation is above the limit. However, there are problems such as mis-clamping or damage to the 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 device capable of clamping a disc without mis-clamping or damage to the disc.

Means for Solving the Problems According to the present invention, a disc is held by a clamper and a turntable while the center of rotation of the disc and the rotation axis of the turntable are aligned with each other, and the disc is held on the turntable. In the disk clamp device, the disk has an inclination that the outer diameter decreases toward the disk, is held by the rotary shaft of the turntable so as to be movable in the rotary shaft direction, and is unclamped on the rotary shaft of the turntable when unclamped. A first holder which is held at a position projecting from the turntable and which is fitted in a center hole of the disc, and which makes a center of rotation of the disc coincide with a rotation axis of the turntable;
Centering member, a first urging means for urging the first centering member in the clamper direction, and an inclination that the outer diameter decreases toward the disc, and the center axis of the clamper is Is movably held in the central axis direction, moves with the clamper, and fits with the center hole of the disc before the center hole of the disc fits with the first centering member when the clamper moves; A second centering member that substantially aligns the center of rotation of the disk with a rotation axis of the turntable; second biasing means that biases the second centering member toward the turntable; It is provided on the rotary shaft of the table, and abuts on the second centering member during the movement of the clamper in the direction of the turntable, and the second centering member causes the clamper and the turntable to contact the disc. Against the second biasing means when clamped housed inside the clamper, formed by and a stopper for preventing contact between the first centering member.

When clamping the working disc, first the clamper is moved toward the turntable. When the clamper moves in the direction of the turntable, first, the second centering member held by the clamper is fitted into the center hole of the disc, and the rotation center of the disc is substantially aligned with the rotation axis of the turntable.

When the second centering member hits the stopper, the second centering member is stopped in place. The clamper further moves in the direction of the turntable while releasing the fitting of the center hole of the disk with the second centering member.

The center hole of the disc is then mated with the first centering member. The first centering member aligns the center of rotation of the disk with the axis of rotation of the turntable. The clamper presses the disc toward the turntable, and clamps and holds the disc with the turntable.

By the first and second centering members, even if the center of rotation of the disc is mounted on the tray with the center of rotation displaced from the rotation axis of the turntable, the disc is clamped by aligning the center of rotation with the rotation axis of the turntable. be able to.

Further, the first and second centering members have an inclination that the outer diameter becomes smaller toward the disc, are movably held in the rotation axis direction, and are rotated by the first and second biasing means. Even if the inner diameter of the center hole of the disc is slightly smaller, the first and second centering members move in the rotation axis direction to fit in the center hole of the disc. The center hole of the disc can be accurately aligned with the rotation axis of the turntable, and the disc can be reliably held between the clamper and the turntable. further,
Since the stopper prevents the first centering member and the second centering member from coming into contact with each other, the second biasing means does not adversely affect the operation of the first biasing means, and the clamp operation is performed. I can do it.

Embodiment FIG. 1 and FIG. 2 are sectional views showing an embodiment of the present invention. In the figure, 17 is a disc tray, 18 is a turntable, 1
Reference numeral 9 indicates a disk clamper. The disc 3 is placed on the disc tray 17 with its recording surface facing downward as in a general compact disc player, and information is read from below by the optical pickup 47. The turntable 18 is press-fitted and fixed to the spindle 20 with its surface facing the label surface of the disc 3 facing downward. Turntable 18
A hole is provided in the center of the surface facing the disk 3 and its periphery, and the yoke 23 and the clamp magnet 24 are held by the magnet holder 25 inside the periphery. Further, the first centering member 26 is loosely fitted to the center of the spindle 20 while being pressed downward by the spring 28, and the stopper 27 is fixed to the spindle 20 by press fitting or E-ring. It has been stopped. The shape of the first centering member 26 is conical (trapezoidal in cross section) so that the centering hole 3a of the disk 3 can be easily fitted. Also, turntable 18
A magnet 29 and a yoke 30 are provided on the opposite side of the facing surface of the disk 3.

The spindle 20 is rotatably supported by a radial bearing 32 provided at the center of a housing 31 on the surface of the turntable 18 on the side having the magnet 29.
The housing portion 31 is provided with a coil 33 and a yoke 34 at a position facing the magnet 29 of the turntable 18, and together with the magnet 29 and the yoke 30 of the turntable 18, constitutes a DC brushless motor.

Since the turntable 18 is attracted to the housing portion 31 side by the magnet 29 and the yoke 30, the housing portion 31 is provided with a thrust bearing 21 which receives the thrust load thereof, and is fixed by a bearing holder 22.

A guide shaft 36 is erected at a position facing the spindle 20 of the lower chassis 35, and a bearing portion 37 press-fitted into the clamper 19 is loosely fitted in a vertically movable manner. A second centering member 38 is loosely fitted on the outer periphery of the bearing portion 37 so as to be vertically movable, and is biased by a spring 39 in the direction of the turntable 18 (upward).

Below the clamper 19, a clamper holder 40 is provided with a bearing 41.
It is slidably fitted onto the guide shaft 36 through. As shown in FIG. 4, the clamper holder 40 is provided with a spring locking portion 49, and a pair of springs 52 are stretched between the spring locking portion 49 and the chassis 35 to move the clamper holder 40 downward. Energize. On the other hand, a shaft fixing plate 42 is provided on the chassis 35, a shaft 43 is fixed to the shaft fixing plate 42, and a clamp arm 44 is swingably attached. The clamp arm 44 is rotated in the direction of arrow E ₁ or E ₂ by a motor and a speed reducer (not shown) to move the clamper holder 40 up and down.

Next, the operation of the disc clamp will be described. In response to a command from the outside, the disc tray 17 is moved to the arrow F ₁ or F ₂
The disk tray 17 can be moved in any direction, and after the disk tray 17 is pulled out of the front panel 45, the disk 3 is placed on the disk guide portion 17a on the disk tray 17 and the disk tray 17 is pulled inside. FIG. 1 shows a state in which the disc 3 is placed on the disc tray 17 and the disc tray 17 is pulled into the apparatus.

When the disc tray 17 moves in the direction of arrow F ₁ and is drawn into a predetermined position in the apparatus, the disc arm 44 is rotated in the direction of arrow E ₁ . By the operation of the disc arm 44, the clamper holder 40 is lifted up against the biasing force of the spring 52 via the sliding member 46 fixed to the clamper holder 40. By raising the clamper holder 40,
The damper 19 and the second centering member 38 also rise via the cushioning material 48. The second centering member 38 is the clamper 19
Since it protrudes from the clamp surface of, the clamper holder 4
When the disc 0 is lifted, the disc 3 is first loosely fitted into the center hole 3a of the disc 3 to center the disc 3.

The upper end of the second centering member 38 is conical,
Centering is possible even if the disc 3 is slightly displaced. Further, the urging force of the spring 39 that urges the second centering member 38 upward is the second weight of the disk 3.
The centering member 38 is adjusted so as not to sink into the clamper 19.

After the disc 3 is centered by the second centering member 38 and the clamper 19 is further raised, the second centering member 38 contacts the stopper 27 provided on the turntable 18, and Clamper 1
9 begins to settle. At the same time, the center hole 3a of the disk 3 is fitted into the first centering member 26, and the disk 20 is precisely centered with respect to the spindle 20.

The clamper 19 further rises and is attracted by the magnet 24 fixed to the turntable 18, and the disc 3
The disk 3 is held on the turntable 18 via the disk, and the disk clamping operation is completed. FIG. 2 shows a state after the completion of the clamp operation. At this time, if the inner diameter of the center hole 3a of the disc 3 is smaller than the maximum outer diameter of the first centering member 26 due to manufacturing error or the like, the center hole 3a of the disc 3 is formed in the tapered portion of the first centering member 26. Receiving, centering the disk 3,
The disk 3 is pushed upward by the clamper 19 and the spring 2
The first centering member 26 is pushed into the turntable 18 against the biasing force of 8, and is brought into close contact with the turntable 18.

Next, the operation of releasing the clamp will be described. A motor (not shown) that drives the clamp arm 44 rotates in a direction opposite to that at the time of clamping, whereby the clamp arm 44 rotates in the direction of arrow E ₂ and the clamper holder 40 urges the spring 48 downward. To start descending.

When the clamper holder 40 descends, the clamper holder 40
The bent portion 51 provided at the upper end of the turntable 1 presses the edge portion 50 provided below the clamper 19,
The adsorption of the clamper 19 by the magnet 24 provided on the reference numeral 8 is released. At this time, the center hole of the disk 3 and the first
Is disengaged from the centering member 26 and is engaged with the second centering member 38. The disc 3 descends together with the clamper 19, and is placed on the disc guide portion of the disc tray 17 while descending. The clamper 19 and the clamper holder 40 are further lowered to the state shown in FIG.

When the disc 3 is taken out or replaced, the disc tray 17 is moved in the direction of arrow F ₂ by an operation of an open switch or the like provided on the front panel 45 or the like, and is pulled out of the device from the front panel 45. 3 can be exchanged.

The device of the present invention is not limited to the one that clamps the disc from the recording surface side of the disc as described above, but can be applied to a device provided with a clamper that clamps the disc from the general label surface side.

Advantageous Effect of the Invention As described above, according to the present invention, when the disc is clamped on the turntable, even if the disc is slightly displaced from the predetermined mounting position, the second centering member causes the disc to be in the middle of the clamping. After the rotation axis of the disk is substantially aligned with the rotation axis of the turntable, the rotation axis is aligned with the first centering member, so that even if the disk is slightly displaced from the predetermined mounting position, mis-clamping does not occur and the disk There is no risk of damaging the disc, and the disc can be clamped and unclamped accurately and reliably, and even if the inner diameter of the center hole of the disc is slightly smaller than the outer diameter of the first centering member, Accurate centering is performed by the inclination of the second centering member, and the first and second centering members resist the biasing force of the first and second biasing means in the rotational axis direction. It is possible to move and securely clamp the disc. Further, since the stopper prevents the first centering member and the second centering member from coming into contact with each other, the second biasing means does not adversely affect the operation of the first biasing means. The first centering member is pushed by the second centering member so that the centering cannot be performed.

[Brief description of drawings]

1 and 2 are cross-sectional views of an embodiment of the present invention, FIG. 3 is a cross-sectional view of an essential part of the embodiment of the present invention, and FIG. 4 is a side view of an essential part of the embodiment of the present invention. FIG. 5, FIG. 6, FIG. 6 and FIG. 7 are cross-sectional views of a conventional example. 3 ... Compact disc, 3a ... Disc center hole,
18 …… Turntable, 19 …… Clamper, 20 ……
Spindle, 24 ... Magnet, 25 ... Magnet holder, 26 ... First centering member, 27 ... Stopper, 28 ... Spring, 29 ... Magnet, 31 ...
… Housing, 33 …… Coil, 36 …… Guide shaft, 3
7 ... Bearing part, 38 ... Second centering member, 39 ... Spring, 40 ... Clamper holder, 44 ... Clamp arm, 48 ... Optical pickup.

Claims (1)

[Scope of utility model registration request] 1. A disc clamp device for holding a disc on the turntable by sandwiching the disc with a clamper and a turntable while making the center of rotation of the disc coincide with the rotation axis of the turntable. Has a slope whose outer diameter decreases toward, and is held by the rotary shaft of the turntable so as to be movable in the rotary shaft direction, and when unclamped, the position protruding from the turntable on the rotary shaft of the turntable. A first hole, which is retained by the first disc and is fitted into the center hole of the disc, and which aligns the rotation center of the disc with the rotation axis of the turntable;
Centering member, a first urging means for urging the first centering member in the clamper direction, and an inclination that the outer diameter decreases toward the disc, and the center axis of the clamper is Is movably held in the central axis direction, moves with the clamper, and fits with the center hole of the disc before the center hole of the disc fits with the first centering member when the clamper moves; A second centering member that substantially aligns the center of rotation of the disk with a rotation axis of the turntable; second biasing means that biases the second centering member toward the turntable; The second centering member is provided on the rotary shaft of the table and abuts on the second centering member while the clamper is moving in the direction of the turntable, and the second centering member is provided between the clamper and the turntable. To A disc clamp device comprising: a stopper that is housed inside the clamper against the second urging means when sandwiched and prevents contact with the first centering member.