JP2547546B2 - Double-sided playback disk player - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a disc player for reproducing information recorded on both sides of a disc.

(B) Conventional technology Conventionally, when playing back a disc recorded on both sides with an optical video disc player, the disc is taken out at the time when the reproduction of the information on one side is completed, and the other side is turned over. Had to play. Therefore, even if the front and back of the disc were inserted by mistake, the disc had to be ejected, turned over, and re-inserted.

Japanese Unexamined Patent Publication (Kokai) No. 57-169936 proposes a technique that enables continuous reproduction of both sides with a single pickup.

In the prior art, the pickup is connected to the movable member through the crank rotation member so as to be rotatable by 180 degrees with respect to the disk surface, so that both surfaces of the optical disk can be continuously recorded or reproduced by one pickup. An optical disc device is disclosed.

(C) Problems to be Solved by the Invention In the above-mentioned conventional technique, continuous reproduction of a disc can be performed without ejecting the disc and turning it over. On the other hand, no measures have been taken and the pickup cannot be automatically moved to the desired reproduction surface designated by the user, and the operation of turning the disc over is indispensable as in the conventional case.

(D) Means for solving the problem The facing surface of the pickup when the disc is mounted is detected and compared with the desired playback surface specified in advance, and the pickup is always moved to the specified playback surface based on this comparison output. It is characterized by being busy.

(E) Operation Since the present invention is configured as described above, the reproduction is started by the desired disc surface regardless of the mounted state of the disc in the disc player.

(F) Example An example of the present invention will be described below with reference to the drawings.

FIG. 2 shows an external view of an optical video disc player, which is a disc tray (disc mounting portion) for setting a disc (2) on the front panel (1) front surface.
(3) can be horizontally moved between the storage position and the withdrawal position. The disc (2) placed on the disc tray (3) is clamped to a turntable (26) driven by a spindle motor (50). Video signals are recorded on both the front surface and the back surface of the disc (2).

On the operation part of the front panel (1), along with various operation buttons such as a PLAY button and a stop button, an A / B designation button (designation that designates whether to start playback from the A side or B side of the disc (2) Means) (1a) are provided.

FIG. 3 is a perspective view of a main part of the pickup feeding device,
A pickup (4) and a feed motor (pickup moving means) (5) are fixed on a movable base (6). A bracket (7) is adhered to the right end of the movable base (6), and a gear (8) is fixed to the motor shaft through the bracket (7). A pinion (pickup moving means) (9) meshing with the gear (8) is pivotally supported on the bracket (7). Two rollers (pickup moving means) (10) and (11) are pivotally supported on the left side surface of the movable base (6).

(12) is a rack that meshes with the pinion (9), and includes a lower linear portion (12a) that extends horizontally on the lower chassis,
An upper linear portion (12c) extending on the lower surface of the upper chassis in parallel with the lower linear portion (12a) and a U-shaped connecting portion (12b) connecting both linear portions are integrated into one body. A guide groove (1) on which the pinion shaft (9a) can be loosely fitted is provided on the inner surface of the connecting portion (12b).
3) extends in a U shape.

(14) is a guide rail on which the rollers (10) and (11) slide, and similar to the rack (12), the lower linear portion (14a),
It is composed of an upper linear portion (14c) and a connecting portion (14b) connecting both linear portions. Like the rack (12), a guide groove (15) into which the roller shaft (10a) can be loosely fitted is provided on the inner surface of the connecting portion (14b), and roller guides are provided on the sliding surfaces of the rollers (10) and (11). A groove (76) is formed.

(16) and (17) are columnar guide poles fixed to the upper and lower chassis (20) and (21), and are arranged parallel to the linear portions of the rack (12) and the guide rail (14). There is.
The guide poles (16) (17) are screwed and fixed on the chassis by screws (19) with a cylindrical fixing member (18) interposed between the guide poles (16) and (17) as shown in FIG.

A fitting hole (22) for fitting with the guide ball (16) is formed on the lower surface of the movable base (6).
2) The lower side is cut out for the escape of the fixing member (18).

The disc (2) placed on the disc tray (3) has upper and lower linear portions (12a) (14a), (12c) (1).
It is clamped by the turntable (26) between 4c).

 Next, the operation of the apparatus of this embodiment will be described.

In the STOP mode, the standby position shown in FIG. 5 and FIG. 6A, that is, the connecting portion (12b) of the lower linear portions (12a) (14a)
(14b) The movable base (6) is located at the immediately preceding position.

The A / B side designation button (1a) is used to specify the A side or B side, and either one of the A side or B side of the disc (2) is on the lower side of the disc tray (3) and the other side is After mounting it so that it is on the upper side, when the PLAY button is turned ON to shift to the PLAY mode, the feed motor (5) starts driving, the driving force is transmitted to the pinion (9) and meshes with the rack (12). At the same time, the movable base (6) moves to the position indicated by B, that is, to the tip position of the lower linear portions (12a) (14a). At this position, the pickup (4) faces the innermost circumference of the lower surface of the disc (2). After that, the spindle motor (25) rotates and the pickup (4) scans the disk (2) for a very short time. By the reproduction for a very short time, the color video signal on the lower surface side of the disc (2), the audio signal of 2 channels, and the digital code added within the predetermined horizontal scanning period of the vertical blanking period of the video signal are taken out. These various signals are demodulated and then inserted into a digital code separation circuit (40) as shown in FIG. 1 to extract only digital codes. Further, the digital code is input to a disc side detection circuit (detection means) (41) to separate only disc side data, and the surface of the disc (2) facing the pickup (4) in the initial state is identified. That is, the disc side data forms a digital code together with frame number data, program time data, chapter number data, etc.
This is for recognizing whether the side is the B side or the B side.

The disc side data thus obtained is input to the comparison circuit (comparison means) (42) together with the output of the A / B designation button (1a), and the coincidence between the two is determined.

As a result of the comparison, the two are the same, that is, the A / B designation button (1a) on the lower surface side of the disc (2) which is the facing surface of the pickup.
If it is the playback surface that you want to playback specified in,
No signal other than the tracking control signal is supplied to the feed motor control circuit (43), and a control signal is supplied to the spindle motor control circuit (44) so as to continue the normal rotation of the spindle motor (25), and the pickup ( The scanning in 4) is continued.

During the scanning, the tracking control circuit of the pickup operates, the output is supplied to the feed motor (5), and the movable base (6) is moved as the lower surface of the disk is scanned.
Is the outer peripheral direction of the disc (2), that is, the lower linear portion (12
a) Move on (14a) toward connecting parts (12b) (14b).
Movable base (6) when scanning of the bottom surface of the disk is completed
Goes through the connecting parts (12b) and (14b) to the upper linear part (12b).
c) It reaches the tip of (14c), reaches the innermost circumferential position of the upper surface of the disk (2), and at the same time, the spindle motor (25) rotates in the reverse direction, and the scanning of the pickup (4) is performed in the same manner as the lower surface of the disk. The movable base (6) moves toward the outer circumference of the disc (2).

FIG. 7 shows a state in which the pickup (4) is scanning the disc (2), that is, the moving state of the lower linear portions (12a) and (14a) of the movable base (6). The guide ball (16) is in the fitted state with the fitting hole (22) in order to prevent the rattling of the pitter up (4) in the vertical and horizontal directions and to improve the tracking accuracy of the pickup. is there.
The same applies to the movement in the upper linear portions (12c) and (14c).

The moving state of the movable base (6) at the connecting portions (12b) and (14b) is shown in FIG. The pinion shaft (9a) and the roller shaft (10a) are loosely fitted in the guide grooves (13) (15) to maintain the meshing between the pinion (9) and the rack (12), and the rollers (10) (11) It moves into the roller guide groove (16) to guide the movement. When the scanning of the upper surface of the disk is completed, the movable base (6) returns to the waiting position and enters the waiting state, and the spindle motor (25) stops.

As a result of comparison by the comparison circuit (42), the two do not match, that is, the reproduction surface on which the lower surface of the disc (2) which is the opposed surface of the pickup (4) is desired to be reproduced specified by the A / B specification button (1a). If it is not, the movable base (6) immediately moves to the lower linear portions (12a) (14a), the connecting portions (12b) (14b) and the upper linear portion after a very short time reproduction operation at the innermost circumference of the disc. The feed motor (5) is controlled by the feed motor control circuit (43) so as to reach the innermost circumference of the upper surface of the disc (2) through the shaped portions (12c) (14c), and the pickup (4) is placed on the upper surface of the disc (2). To start scanning. At this time, the spindle motor (25) is controlled by the spindle motor control circuit (44) so as to rotate in the direction opposite to the scanning of the disk lower surface. When the scanning of the top surface of the disk is completed,
The movable base (6) reaches the innermost circumference of the lower surface of the disc through the connecting portions (12b) (14b) and the lower linear portions (12a) (14a), and the spindle motor (25) reverses again at this position. ,
Further, the lower surface of the disc of the pickup (4) is scanned. Movable base (6) when scanning the underside of the disk is completed
Returns to the waiting position and enters the waiting state, and the spindle motor (25) stops.

Therefore, A of the disc (2) is placed on the disc tray (3).
With the side facing down and the side B facing up, the A / B designation button (1a)
When the A side is designated, or the B side is placed on the lower side and the A side is placed on the upper side, and the B side is designated, the movable base (6) is A → B → A → C → A in FIG. In the case opposite to the above, that is, the A side is on the lower side, the B side is on the upper side, and the B side is designated, or the B side is on the lower side and the A side is on the upper side.
When the surface is designated, the movable base (6) is A → B → A → C →
Move from A to B to A. However, at the time of the first movement of A → B → A, the reproduction of the lower surface of the disc is performed only for a very short time to detect the opposite surface.

FIG. 9 is a flowchart showing the series of operations described above. In this flowchart, PU indicates the pickup (4), the step (50) is the pickup (4) on the innermost circumference of the disc bottom surface, and the step (51) is the pickup (41).
Indicates that it reaches the innermost circumference of the disc upper surface.

In this embodiment, once one of the A side and the B side is designated by the A / B designation button (1a), when the reproduction of the designated disc surface is completed, the other side is automatically reproduced. However, it is also possible to return the movable base (6) to the waiting position and reproduce only one surface when the reproduction of only the specified surface is completed without continuous reproduction. is there.

(G) Effect of the Invention As described above, according to the present invention, it is possible to start reproduction from a desired disc surface without considering the front and back of the disc when mounting the disc, and the reproduction is performed first. With only a single operation of designating a desired disc surface, double-sided reproduction from the designated surface to the other surface can be automatically executed, and a new function can be added to the disc player without any troublesome operation. Further, when determining the orientation of the mounted disc, the rotation direction of the turntable is determined in advance, and reproduction of a predetermined surface is performed to obtain side information.
Spindle servo is quickly applied when distinguishing between front and back,
The time for front / back discrimination can be minimized.

[Brief description of drawings]

The drawings are all related to one embodiment of the present invention, FIG. 1 is a circuit diagram,
2 is an external view, FIG. 3 is a perspective view of main parts, FIG. 4 is an explanatory view of a guide ball, FIG. 5 is a top view, FIG. 6 is a side view, and FIG. 7 is an explanatory view during horizontal movement. , FIG. 8 is an explanatory diagram during the U-turn, and FIG. 9 is a flowchart. (1a) ... A / B designation button (designation means), (2) ... disc, (3) ... disc tray (disc mounting part),
(4) ... pickup, (5) ... feed motor (pickup moving means), (41) ... disk side detection circuit (detection means), (42) ... comparison circuit (comparison means).

 ─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-56-77953 (JP, A) JP-A-59-175066 (JP, A) JP-A-57-105862 (JP, A) Actual development Sho-57- 30865 (JP, U) Actual development Sho 56-174156 (JP, U)

Claims (1)

(57) [Claims] 1. A pickup for selectively reproducing information on both the front surface and the back surface of a disc, and a turn in which the disc is mounted and the rotation direction of which changes according to the reproduction surface of the disc by the pickup. A table and a state in which the disc is mounted on the turntable, the turntable is rotated in a predetermined direction, the opposing disc surface is reproduced for a short time by the pickup at a predetermined initial position, and a reproduction signal obtained is obtained. Detecting means for detecting the disc surface facing the pickup based on the side information of the pickup, designating means for designating the preceding reproduction surface desired to be reproduced first in the disc, the detecting means output and the designating means output. Comparing means for comparing, and moving the pickup to the side of the preceding reproduction surface based on the output of the comparing means. No playback of the serial preceding reproducing surface,
A double-sided reproduction disc player comprising a pickup moving means for moving the pickup to the opposite surface side so as to reproduce the opposite surface opposite to the preceding reproduction surface after the completion of the reproduction.