JPH01162269A - Disk centering device for disk player with double side performance - Google Patents

Abstract

PURPOSE:To surely and easily perform a switching operation with high accuracy by intermittently moving two stages of a supporting member. CONSTITUTION:Cam grooves 38a and 39a are formed in the cam groove in step shape as a whole. Therefore, the supporting member 31 moves two stages intermittently according to the movement of moving members 38 and 39. In other words, the device is constituted in such a way that a first centering part 27 is fitted in the central hole of the circular substrate, and the centering of a circular substrate 25 is performed on a turntable at the time of performing the reproduction and recording of the signal recording layer of the circular substrate on one side, and a second centering member 36 is fitted in the central hole of the circular substrate on the other side, and the centering of the circular substrate is performed on the turntable at the time of reproducing and recording the signal recording layer provided at the circular substrate 24 on the other side. Therefore, even when a pair of circular substrates are deviated from each other, the centering of both circular substrates can be performed accurately on the turntable.

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a centering device for an information recording disc, and in particular,
The present invention relates to a disc centering device for a double-sided disc player that plays both sides of an information recording disc consisting of a pair of circular substrates each having a signal recording layer.

Background Art Optical information recording discs, such as video discs or D RAW (Direct Read After)
In the case of a (write) disc, since information is recorded as a large number of minute bits by a laser beam spot, it is important to protect the layer in which pits are formed, that is, the signal recording layer. For this reason, a type has been developed in which a pair of circular substrates, both of which have a signal recording layer, are bonded to face each other with the signal recording layer on the inside.

FIG. 6 shows a conventional example of a disc centering device for centering the disc with respect to a turntable in a double-sided performance disc player that plays both sides of the information recording disc. As shown in FIG. 6, the disc centering device includes a centering member 4 having a tapered portion 1 on the outer periphery and slidably attached to a drive shaft 3 of a turntable 2; and a ring stopper 6 that prevents the centering member 4 from being removed from the drive shaft 3.

Note that the bowl-shaped suppressing member 8 clamps the disc 9 to the turntable 2, and the ball 10
It is rotatably attached to a support member 12 via a ball seat 11, and is attached to and detached from the disk 9 placed on the turntable 2 by vertical movement of the support member 12.

As described above, the disk 9 is formed by bonding a pair of circular substrates 13 and 14, each having a signal recording layer and a center hole, with the signal recording layer on the inside.

In the disc centering device configured as described above, the disc 9 is centered with respect to the turntable 2 by engaging the tapered portion 1 of the centering member 4 with the center hole of the disc 9 as shown in the figure. Ru. In this state, the recording and reproducing section 16 records and reproduces information on the signal recording layer of one of the circular substrates 13, and
Without turning the disk 9 upside down, the other recording/reproducing section 17 records and reproduces information on the signal recording layer of the other circular substrate 14.

In this way, two recording/reproducing sections 16.17 are provided to correspond to each signal recording layer of the circular substrate 13.14, so that recording and reproduction can be performed on both signal recording layers without reversing the disk 9. In this case, when the pair of circular substrates 13 and 14 forming the disk 9 are connected to each other with an offset of e as shown in the figure, the following problem occurs.

That is, recording and reproducing on the signal recording layer of one of the circular substrates 13 that is in contact with the disk supporting surface of the turntable is performed smoothly, but the central axis of the other circular substrate 14 is e.g. from the central axis of rotation of the turntable 2. Since the circular substrate rotates while being deviated by a certain amount, it is difficult to smoothly perform recording and reproduction on the signal recording layer of the circular substrate.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned points, and its object is to provide a turntable for both circular substrates that constitute an information recording disk even when the two circular substrates are shifted from each other. To provide a low-cost disk centering device that can always accurately center a disk.

A disk centering device according to the present invention is for centering an information recording disk formed by attaching a pair of circular substrates, each having a signal recording layer and a center hole, with the signal recording layer facing inside. , a first centering member that can be fitted into the center hole of one of the circular substrates that is provided so as to be freely protrusive and retractable from the disk supporting surface of the turntable and along the rotation center axis of the turntable, and that comes into contact with the disk supporting surface; a biasing means for biasing the first centering member in the projecting direction; a support member movable in a plane substantially perpendicular to the disk supporting surface; and a drive for moving the support member. and a second centering member rotatably attached to the support member and capable of fitting into a center hole of the one circular substrate, when the second centering member fits into the center hole. The first centering member is recessed from the disk supporting surface of the turntable, and the driving means includes a moving member that has a cam groove that engages with the supporting member and is movable in a predetermined direction, and a driving force applied to the moving member. the cam groove is formed so that the supporting member moves when the movable member moves, and the cam groove includes a plurality of linear portions extending in the moving direction of the movable member. , a step-like cam groove consisting of a diagonal portion that is continuous with each of the linear portions and is inclined with respect to the linear portion.

Embodiment Hereinafter, a disk centering device as an embodiment of the present invention will be explained with reference to the accompanying drawings.

As shown in FIG. 1, the turntable 21 is fitted onto a spindle 22 and rotated by a motor including the spindle. The information recording disk 23 to be centered with respect to the turntable 22 is formed by attaching a pair of circular substrates 24 and 25, each having a signal recording layer and a center hole, to each other so that the signal recording layer is on the inside. A recess 22a is provided in the center of the turntable 22,
A first centering member 27 is provided in the recess so as to be freely protrusive and retractable relative to the disk supporting surface of the turntable 22 and along the rotation center axis of the turntable. The first centering member 27 is slidably fitted onto the spindle 22 and guided by the spindle.

The first centering member 27 has a tapered surface 27a on the outer periphery,
A pair of circular substrates 24 forming an information recording disk 23.
The circular substrate 25 is centered with respect to the turntable 21 by fitting the tapered surface into the center hole of one of the circular substrates 25 that contacts the disk supporting surface of the turntable 21. A coil spring 29 is interposed between the turntable 21 and the first centering member 27, which applies a bias force to the first centering member in the projecting direction.

As shown in FIG. 2, a support member 31 is disposed above the turntable 21, and the supporting member 31 is provided above the turntable 21, and is supported in the vertical direction (the direction of the arrow 2 and the opposite direction) perpendicular to the disk supporting surface of the turntable. It is movable. An opening 31a is formed in the center of the support member 31, and a leaf spring 3 is attached to the support member 31 so as to close this opening 31a.
2 is installed. As shown in FIG.
A rotating member 33 is rotatably attached to the lower surface of 2 via a bracket 32a. A disc-shaped leaf spring 34 is fixed at the center of the rotating member 33, and a spring 34 is provided at the outer periphery, that is, at the free end, for pressing the information recording disc 23 against the disc supporting surface of the turntable 21. A pressing member 35 is fixed. A second centering member 36 is attached to the rotating member 33 together with a leaf spring 34 .

A tapered surface 36a is formed on the outer peripheral part of the second centering member 36, and the tapered surface is fitted into the center hole of the circular substrate 24 forming the information recording disk 23 to center the circular substrate 24 with respect to the turntable 21. to do. Note that a hemispherical abutment part 36b is formed at the upper end of the second centering member 36, and a receiver fixed to the center part of the lower surface of the leaf spring 32 is attached to the member 3.
This contact portion 36b can smoothly slide into contact with 2b. Further, a cylindrical portion 36c extending toward the turntable 21 is formed in the center portion of the second centering member 36, and a center hole 36d of the cylindrical portion is fitted onto the tip of the spindle 22, thereby forming a second core. The centering member 36 is centered with respect to the turntable 21.

As shown in FIG. 2, a pair of rectangular plate-shaped moving members 38 and 39 are arranged so as to sandwich the supporting member 31 from the left and right sides, and in the front-back direction (direction of arrow Y and the opposite direction).
It is capable of reciprocating motion. As shown in FIG. 3, a total of four bottles 31 are provided, two on each side of the left and right sides of the support member 31, and are inserted into cam grooves 38a and 39a formed in each moving member 38 and 39, respectively. The pins are slidably engaged. Each of the cam grooves 38a and 39a as a whole is inclined downward (in the opposite direction to the arrow Z direction) toward the front (in the direction of the arrow Y). That is, the supporting member 31 is moved up and down by moving the moving members 38 and 39 back and forth. Each of the cam grooves 38a and 39a extends in the moving direction of each moving member 38.
9d, and two slanted parts 38e, 38f, 39e and 39 that are continuous with each linear part and are inclined with respect to the linear part.
f, and the overall shape is a step-like cam groove. Therefore, as each of the moving members 38 and 39 moves, the supporting member 31 intermittently moves in two stages.

Rack portions 38g and 39g are formed at the lower front end of each moving member 38 and 39 along the moving direction thereof. A synchronous shaft 41 is provided near each moving member 38 and three
is rotatably provided, and a pair of gears 41a and 41b fitted to both ends of the synchronization shaft move each moving member 3
8.39 are meshed with rack portions 38g and 39g, respectively. A gear 42a fitted to the output shaft of a motor 42 meshes with one gear 41a. That is, as the motor 42 rotates, the support member 31 is moved up and down.

As shown in FIG. 1, a pair of recording and reproducing sections 44 and 45 are arranged to vertically sandwich the information recording disk 23 placed on the turntable 21, and a guide drive (not shown) is provided. It is guided and moved along the recording surface of the information recording disk 23 by the means. The circular substrate 24 is
Signal recording and reproduction are performed on the signal recording layer 25 and 25.

Next, the operation of the disk centering device having the above-mentioned structure will be briefly explained with reference to FIGS.

First, a pair of circular substrates 24.2 forming the disk 23
When recording or reproducing information on the signal recording layer of one of the circular substrates 25 that is in contact with the disk supporting surface of the turntable 21, the motor 42 rotates and moves the moving member as shown in FIG. 38 and 39 are moved to approximately the midpoint of their movement strokes.This results in the state shown in FIG. In response, the first centering member 27 engages the center hole of the circular substrate 25 with its tapered surface 27a to center the circular substrate with respect to the turntable 21. In this state, the lower recording/reproducing section 45 shown in FIG. 1 records and reproduces information.

Next, when recording and reproducing information regarding the signal recording layer of the other circular substrate 24, the motor 42 rotates further and the moving members 38 and 39 move to the end point position of their movement stroke, as shown in FIG. The state shown in FIG. 5 is reached. That is, the second centering member 36 fits into the center hole of the circular substrate 24 with its tapered surface 36a. Further, immediately before this, the cylindrical portion 36c of the second centering member comes into contact with the first centering member 27, and the first centering member 27
5 and sinks below the disk supporting surface of the turntable 21. By this operation, the circular substrate 24 is centered with respect to the turntable 21. Thereafter, the upper recording/reproducing section 44 shown in FIG. 1 records and reproduces information.

Effects of the Invention As detailed above, the disk centering device according to the present invention centers an information recording disk formed by bonding a pair of circular substrates each having a signal recording layer and a center hole, and is capable of centering a disk of a turntable. a first centering member that can be fitted into a center hole of one of the circular substrates that is provided so as to be freely protrusive and retractable with respect to the support surface and along the rotation center axis of the turntable and that comes into contact with the disk support surface; a biasing means for biasing the centering member in a projecting direction; a support member provided movably in a plane substantially perpendicular to the disk supporting surface; a drive means for moving the support member; and a drive means for moving the support member. a second centering member that is rotatably attached to the member and that can be fitted into the center hole of the other circular substrate, and when the second centering member is fitted into the center hole, the first centering member The member is removed from the center hole of the circular substrate and submerged below the disk carrying surface of the turntable.

That is, when performing reproduction or recording on the signal recording layer of one circular substrate, the first centering member fits into the center hole of this circular substrate to center the circular substrate with respect to the turntable, and When performing reproduction or recording on the signal recording layer provided on the turntable, the second centering member is fitted into the center hole of the other circular substrate to center the circular substrate with respect to the turntable. ing.

Therefore, even if the pair of circular substrates are shifted from each other, both sun-shaped substrates can always be accurately centered with respect to the turntable.

Further, the supporting member and the driving means, which are the constituent members of the disk centering device according to the present invention, can also be used as constituent members of the disk clamp mechanism that presses the information recording disk onto the turntable, thereby making it easier to reduce costs. It has become.

Furthermore, in the disk centering device according to the present invention, the driving means includes a moving member that has a cam groove that engages with the supporting member and is movable in a predetermined direction, and a drive that applies a driving force to the moving member. The cam groove is formed such that the support member moves when the movable member moves, and the cam groove includes a plurality of linear portions extending in the direction of movement of the movable member, and a force applying means. The stepped cam groove is made up of a slanted part that is continuous with each part and is inclined with respect to the straight part.

In this way, the step-like cam grooves cause the supporting member to move intermittently in two stages, thereby switching the engagement and disengagement of the first and second centering members with the disk, so that the switching operation is possible. This can be done reliably, accurately, and easily.

[Brief explanation of the drawing]

FIG. 1 is a front view including a partial cross section of a disk centering device according to the present invention and its peripheral mechanism, and FIGS. 2 and 3 are perspective views of a portion of the disk centering device shown in FIG. 1. and a side view, FIG. 4 (FIGS. 5 to 5 are diagrams for explaining the operation of the disk centering device shown in FIGS. 1 to 3,
FIG. 6 is a partially sectional front view of a conventional disk centering device and its surrounding mechanisms. Explanation of symbols of main parts 21...Turntable 23...Information recording disk 24.25...Circular substrate 27...First centering member 29. ... Coil spring 31 ... Support member 32, 34 ... Leaf spring - 33 ... Rotating member 35 ... Pressing member 36 ... ...Second centering member applicant Pioneer Corporation

Claims (2)

[Claims] (1) A pair of circular substrates, each having a signal recording layer and a center hole, are attached to each other so that the signal recording layer is on the inside, and an information recording disk is centered on the turntable of a double-sided disc player. The disk centering device includes a center hole of one of the circular substrates, which is provided so as to be freely protrusive and retractable from the disk supporting surface of the turntable and along the rotation center axis of the turntable, and abuts the disk supporting surface. a first centering member that can be fitted into the disc, a biasing means that biases the first centering member in a projecting direction, and a support member that is movable in a plane substantially perpendicular to the disk supporting surface. a driving means for moving the support member; and a second centering member rotatably attached to the support member and capable of being fitted into a center hole of the other circular substrate relative to the one, the second centering member When the member is fitted into the center hole, the first centering member is recessed from the disk supporting surface, and the driving means has a cam groove that engages with the support member, and is a moving member that is movable in a predetermined direction. and a driving force applying means for applying a driving force to the moving member, the cam groove is formed so that the supporting member moves when the moving member moves, and the cam groove is formed in a direction in which the moving member moves. A disk centering device characterized in that it is a step-like cam groove comprising a plurality of linear portions extending in the cam groove, and a diagonal portion continuous with each of the linear portions and inclined with respect to the linear portion. (2) A patent claim characterized in that when the outer peripheral portion of the second centering member reaches the vicinity of the disk supporting surface, the center portion of the second centering member comes into contact with the first centering member. The disk centering device according to item 1.