JPH0311017B2 - - Google Patents

Description

[Detailed description of the invention] Technical field The present invention relates to a disc player.

Background technology In recent years, digital audio disks (hereinafter referred to as
(abbreviated as DAD), by recording digital signals, it can accommodate a larger amount of information than conventional audio disks that record analog signals, and generates less noise during playback. Several types of disks have been developed and are widely used.

Since the DAD is rotated at an extremely high rotation speed compared to the above-mentioned audio disks, the DAD
A disc player that plays the DAD is provided with a clamping mechanism for firmly clamping the DAD onto the turntable. FIG. 5 shows the main parts of a clamp mechanism and a turntable provided in a conventional disc player.

As shown in FIG. 5, an annular protrusion 2 is formed on the outer periphery of a disc-shaped turntable 1, and the turntable 1 supports a disk 3 on the annular protrusion. do. On the other hand, an annular projection 5 that contacts the main surface of the disk 3 is also formed on the outer periphery of the disk-shaped pressing member 4, which is a main member of the clamp mechanism and cooperates with the turntable 1 to perform a disk clamping action. The diameters of both these annular projections 2 and 5 are approximately equal.

The pressing member 4 is rotatably supported via a spherical bearing member 7 by a support member 6 that is movable with respect to the turntable 1 . A guide portion 8 is protruded from the center of rotation of the turntable 1 and fits into the center hole of the disk 3 to position the disk 3 with respect to the turntable. A recess 9 is formed with a circular cross section perpendicular to the rotation center axis. This recess 9 is located at the center of rotation of the pressing member 4.
A cylindrical protrusion 10 is formed which fits into the cylindrical protrusion 10 .
These recesses 9 and protrusions 10 constitute centering means for centering the pressing member 4 with respect to the turntable 1.

In the disk player having such a structure, there is a problem in that the disk 3 tends to vibrate at the portions sandwiched by the annular protrusions 2 and 5 as so-called nodes, as shown in FIG. In order to suppress this vibration, a vibration isolating member such as a rubber plate has been provided on the contact surface of the pressing member 4 with the disk 3, but a sufficient effect has not been obtained.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and its object is to provide a disk player that can suppress vibrations of a clamped disk.

A disc player according to the present invention includes a playing means including a disc-shaped turntable, and a clamp mechanism for clamping a disc placed on the turntable, and the turntable has an annular protrusion formed on its outer periphery. carries a disk,
The above clamp mechanism comes into contact with the main surface of the disk.
It has a disk-shaped pressing member in which two annular projections are formed concentrically around the central axis of rotation and cooperates with the turntable to perform a disk clamping action, and the diameter of the annular projection of the turntable is the same as that of the pressing member. The diameter of one of the two annular protrusions is larger than the diameter of the other and smaller than the diameter of the other.

Embodiment Hereinafter, main parts of a disc player as an embodiment of the present invention will be described with reference to the accompanying drawings.

As shown in FIG. 1, a disc-shaped turntable 21 is directly rotationally driven by a spindle motor 23 fixedly mounted on a chassis 22. As shown in FIG. A carriage 24 in which an optical pickup means (not shown) is disposed is disposed on the chassis 22, and is adapted to move along a plane including the disk carrying surface of the turntable 21. A bracket 26 projects from the lower surface of the chassis 22, and a support member 28 is swingably attached to the bracket via a pin 27. The pin 27 extends parallel to the disk supporting surface of the turntable 21, so that the support member 28 swings in a plane perpendicular to the disk supporting surface of the turntable 21. As is clear from FIG. 2, a disk-shaped pressing member 30 is rotatably attached to the free end of the support member 28 via a spherical bearing member 31, which cooperates with the turntable 21 to perform a disk clamping action. ing. As shown in FIG. 1, the free end of support member 28 and chassis 22
A coil spring 32 is interposed between them, and the support member 28 is biased by the coil spring in a direction in which the pressing member 30 approaches the turntable 21. The above-mentioned bearing member 31 is provided at the rotational center of the pressing member 30 so as to be movable within a predetermined range along the rotational center axis of the pressing member, and is in smooth contact with the support member 28.

As is clear from Fig. 2, turntable 2
An annular protrusion 34 is formed on the outer periphery of the turntable 1 and extends around the entire circumference of the turntable 2.
1 supports a disk 35 on the annular projection. On the other hand, the pressing member 30 also has two annular projections 36 and 37 that abut against the main surface of the disk 35 and are formed concentrically about the central axis of rotation of the pressing member. Annular projection 3 provided on turntable 21
4 is larger than the diameter of one of the two annular projections 36 formed on the pressing member 30 and smaller than the diameter of the other annular projection 37.

As is clear from Fig. 2, turntable 2
A guide portion 39 that fits into the center hole of the disk 35 to accurately position the disk 35 with respect to the turntable is protruded from the center of rotation of the turntable. A recess 40 is formed with a circular cross section perpendicular to the rotation center axis of the table. On the other hand, a cylindrical protrusion 41 that fits into the recess 40 is formed at the center of rotation of the pressing member 30 . As is particularly clear from FIG. 3, which is a view in the direction of the arrows in relation to FIG. A spherical movable piece 43 is provided and is movable in the radial direction of the pressing member 30. The three movable pieces 43 are in contact with the inner peripheral surface of the recess 40 and the upper end of the spherical bearing member 31, and are brought into pressure contact with the inner peripheral surface of the recess 40 when the bearing member moves in a direction approaching the turntable 21. .

The three movable pieces 43 described above will be referred to as second movable pieces, and on the other hand, the spherical bearing member 31 will be referred to as first movable piece. These second movable pieces and the recess 4
0 and the protrusion 41, the turntable 21
A centering means for centering the pressing member 30 with respect to the centering member 30 is configured.

FIG. 4 shows a state in which the disk 35 is clamped, and as is clear from the figure, the three movable pieces 43 are moved by the component of the clamping force transmitted from the bearing member 31, which is the first movable piece. is pressed against the inner circumferential surface of the recess 40. Thereby, the pressing member 30 is accurately centered with respect to the turntable 21. Furthermore, when the disk vibrates as shown in FIG. 5, the annular protrusion 34 of the turntable 21 suppresses the so-called peak of this vibration, as shown in FIG. 4, and the vibration is damped. .

The projection 41 of the pressing member 30 is provided with a restriction portion 45 that restricts the movement of the bearing member 31, which is the first movable piece, in the direction approaching the turntable 21 at a predetermined movement position. 4
The pressing force of the movable piece 43 against the inner circumferential surface of 0 is always constant. Further, although the first and second movable pieces described above are spherical members, by configuring them in this way, commercially available high-precision spherical bearing members can be used as the respective movable pieces, and the cost is reduced. It is also possible to reduce the

Furthermore, each annular projection 34 provided on each disk contact surface of the turntable 21 and the pressing member 30,
The rings 36 and 37 may each have a completely continuous ring shape, or may have a shape in which a portion of the ring is missing, for example, at equal pitches.

Effects of the Invention As detailed above, the disc player according to the present invention includes a playing means including a disc-shaped turntable, and a clamping mechanism for clamping a disc placed on the turntable, and the turntable The disc is supported by an annular protrusion formed on the outer periphery of the clamp mechanism, and the clamp mechanism has two annular protrusions that contact the main surface of the disc and are formed concentrically around the central axis of rotation, and cooperate with the turntable. The turntable has a disc-shaped pressing member that performs a disk clamping action, and the diameter of the annular projection of the turntable is larger than the diameter of one of the two annular projections of the pressing member and smaller than the diameter of the other. In other words, against vibration of the disk,
Since the annular protrusion of the turntable suppresses the so-called peak of the vibration, the vibration of the disk is effectively damped and suppressed.

[Brief explanation of the drawing]

FIG. 1 is a side view of the main parts of a disc player according to the present invention, FIGS. 2 and 3 are partial detailed views of the main parts, and FIG. 4 is a diagram for explaining the operation of the main parts.
FIG. 5 is a diagram for explaining the main parts of a conventional disc player. Explanation of symbols of main parts, 21... Turntable, 28... Support member, 30... Pressing member, 31
... Bearing member, 34, 36, 37 ... Annular projection, 35 ... Disc, 40 ... Recess, 41 ...
...Protrusion, 43...Movable piece.

Claims (1)

[Claims] 1. A performance means including a disc-shaped turntable, and a clamping mechanism for clamping a disc placed on the turntable, the turntable supporting the disc on an annular protrusion formed on its outer periphery; The clamping mechanism includes a disc-shaped pressing member in which two annular protrusions that contact the main surface of the disc are formed concentrically around the central axis of rotation thereof, and cooperate with the turntable to perform a disc-clamping action. , the diameter of the annular projection of the turntable is 2 provided on the pressing member.
A disc player characterized in that one of the two annular protrusions has a diameter larger than the other and smaller than the other diameter.