JPH0468701B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a playback device for a disc in which information is recorded on both the front and back sides.

(b) Prior Art To play the front and back sides of a record or disk on which information such as audio signals and video signals are recorded, after playing one side of the record, the record is removed from the player, turned over, and placed back into the player. Generally, a device is constructed so that one side is set and the other side is played, but when playing both sides continuously, the operability is extremely poor.

Therefore, special public relations number 1986-4762 (G11B3/
085), a roughly U-shaped guide means is provided to move the linear tracking arm from one side to the other side, and after one side of the record is played back by the linear tracking arm, the record is rotated. A technique has been proposed in which the motor is reversed and the linear tracking arm is moved to the other side using guide means for regeneration.

(c) Problems to be Solved by the Invention When performing double-sided playback of a disc as in the prior art described above, especially in the access mode or program mode in which the pick-up is transferred to a predetermined chapter on side A or B, information on the access destination is In addition to the chapter number, side information indicating whether side A or B is also essential. Therefore, when the operator accesses a predetermined chapter, it is necessary to display this side information as well, but depending on the disk, this side information may not be recorded, making it difficult to specify the predetermined chapter. .

(d) Means for Solving Problems The present invention mechanically detects which side of the disk the pick-up faces, and based on this, when side information is not recorded on the disk, , is characterized by displaying whether the disk is on the top or bottom surface.

(E) Effect Since the present invention is configured as described above, even if side information is not recorded, it is possible to issue a pick-up access command between both sides.

(f) Examples Embodiments of the present invention will be described below with reference to the drawings.

Figure 2 is a perspective view of the pick-up drive mechanism;
The figure is a schematic explanatory diagram of the pick-up movement. 6 is a support base (pick-up movement Pinions 12 and 13 driven by a feed motor 5 are pivotally supported on both sides via a drive force transmission mechanism (not shown), and two guide rollers (not shown) are rotated on each side. It is freely pivoted. On the bottom
A linear guide pole 3 is fixed to the lower chassis 49a, 49b so as to extend in the radial direction of the disk.
A guide hole 36 into which 1 and 30 can be fitted is formed.

Reference numerals 17 and 18 denote a pair of support blocks that guide the movement of the support base 6, and include upper linear portions 17a and 18b extending upwardly on the disk 9, and extending downward parallel to the upper linear portions. lower straight parts 17c, 18c, both straight parts 17a, 18a,
Connecting parts 17b, 18b connecting 17c, 18c
It has a U-shape consisting of. Racks 19, 20 and guide grooves 21, 22 are formed on opposing inner peripheral surfaces of the support blocks 17, 18.

The pinions 12 and 13 are engaged with the racks 19 and 20, and the guide rollers are connected to the guide grooves 21 and 22, respectively.
By loosely fitting the support base 6 into the support blocks 17 and 1 as the feed motor 5 is driven.
8 and while the lower linear portions 17c and 18c are moving, the guide hole 30 is fitted into the guide hole 36 and guided linearly, making it possible to scan the lower surface of the disk 9, and while the lower linear portions 17c and 18c are moving, the guide hole 30 is fitted into the guide hole 36 and guided linearly, making it possible to scan the lower surface of the disk 9. While moving the guide pole 18a, the guide pole 31 is fitted into the guide hole 36 and guided in a straight line, making it possible to scan the top surface, and by moving the connecting parts 17b and 18b, continuous scanning of the bottom and top surfaces is possible. becomes.

Next, the first circuit diagram, which is a circuit block diagram of the device of this embodiment, will be described.
The operation will be explained with reference to the figure.

Information recorded on disk 9 is picked up 4
and sent to the information analysis section (side information detection means) 50 and the demodulation circuit 51. The information analysis section 50 separates data codes such as frame numbers and chapter numbers inserted as codes in predetermined lines of the vertical blanking period of the video signal. Particularly in the 16th H of the vertical blanking period, side information is recorded to determine whether the information is recorded on the A side or the B side of the disc, and the information analysis unit 50 records this side information. The information is also separated and input to the main control circuit 52.

On the other hand, reference numeral 53 denotes a mechanical determination section (opposing surface detection means) that mechanically determines whether the side of the disk being played back by the pickup 4 is the top or bottom surface. The mechanical determination section 53 is connected to the upper and lower linear portions 18 of the support block 18.
It is composed of upper and lower lead-in switches 70 and 71 arranged at the ends of the switches a and 18c.

Normally, when regenerating the lower surface of the disk, after the spindle motor 25 is rotated in the normal direction, the support base 6 is connected to the lower linear portion 17c of the support block 18,
18c and lower lead-in switch 7.
1 is moved by the driving force of the feed motor 5 to a position where it is turned on by a pressing protrusion 6a provided on the side surface of the support base 6, and this lower lead-in switch 7
1, the feed motor 5 rotates in reverse and starts scanning the lead-in section with 900 tracks on the innermost circumference of the lower surface of the disk. During this scanning, when the spindle motor 25 reaches a rotational speed (1800 rpm) at which information can be reproduced, a lead-in signal is read out. Immediately after reading out this lead-in signal, a track jump is performed to escape from the lead-in section, and multiple The play track on which the information of the chapter is recorded is played back. Here, when playing back each side of the disc, the pickup 4 always scans the lead-in part on the innermost circumference of the disc, and at the same time the spindle motor 25 is rotated at 1800 rpm to detect the lead-in signal. CAV
This is to accommodate not only CLV (constant angular velocity) but also CLV (constant linear velocity) systems. That is, in a CLV disk, it is necessary to change the rotation speed of the spindle motor according to the position in the radial direction, and therefore it is necessary to read information at the innermost circumference, where the rotation speed of the spindle motor 25 is determined. . This operation is the same when playing a program starting from a predetermined chapter.

Also when reproducing the upper surface of the disk, the spindle motor 25 is rotated in the opposite direction to that when reproducing the lower surface, and the support base 6 is first moved to the upper linear portion 17a,
18a and turn on the upper lead-in switch 70, the lead-in section is regenerated, and after the spindle motor 25 reaches a rotational speed (1800 rpm) at which information can be regenerated, the upper play track is regenerated. will be done. Therefore, the lower side reproduction is performed immediately after the lower lead-in switch 71 is turned on, and the upper side reproduction is performed immediately after the upper lead-in switch 70 is turned on.

The mechanical determination unit 53 connects upper and lower lead-in switches 70 and 71 to the R and S terminals of an R-S flip-flop, respectively, and
By configuring the R terminal to be at H level when 70 is ON, and the S terminal to be at H level when lower lead-in SW 71 is ON, the L level is set to L during top side playback.
When the bottom side is reproduced, a side judgment output of H level is generated.

The main control circuit 52 receives the side information from the information analysis section 50 and the side judgment output from the mechanical judgment section 53, and when both are input, that is, when side information is recorded on the disc being played back, The side information is sent to the character generation section 54 in the subsequent stage.
Furthermore, if side information is not input, that is, if side information is not recorded on the disc, a side determination output is output to the character generation section 54.

When the character generation unit (display means) 54 receives the side information, it displays “SIDE 1” (when playing side A) and “SIDE 2”.
This is a character generator that outputs the character signal (during B-side playback), and when the side judgment signal is input, when the side judgment signal is at H level, "SIDE U" (U: abbreviation for upper), Generates a character signal of "SIDE L" (L: abbreviation for LOWER) when it is at L level. Here, during bottom-side playback, the side judgment output is at H level, but the character signal corresponds to "SIDE U," and conversely, during top-side playback, the side judgment output is at L level, but the character signal corresponds to "SIDE L." This is due to the following reasons. In a normal disc, a label for guiding information on side A is attached inside the lead-in section of side B, and a label for guiding information on side B is attached inside the lead-in section for side A. That is,
The labels that provide information on each side are related to the information on the side opposite to the side on which the label is attached;
The user perceives that the information on the top surface of the disk set on the turntable 26 is provided by a label affixed to the same top surface, that is, the user's perception and reality are opposite. When displaying, the relationship between the side judgment output and the character signal is reversed as described above in order to give priority to the display of the apparent scanning plane as perceived by the user, rather than the true scanning plane. be.

The character signal generated by the character generation section 54 is combined with the demodulated video signal demodulated by the demodulation circuit 51 and the synthesizer 55, and displayed on the TV 56.

FIG. 4 is a diagram showing the display status of character signals on the TV 56. A shows the case where there is side information, and "SIDE 1" or "SIDE" is displayed at the top of the screen.
2” and the chapter signal separated by the information analysis unit 50 are displayed.B is a case where there is no side information, and instead of “SIDE 1” or “SIDE 2”, “SIDE U” or "SIDE L" is displayed.Furthermore, when accessing a predetermined chapter, the side to be accessed and the chapter number are displayed in parallel at the bottom of the display in Figure 4.5.
The figure shows a flowchart of this embodiment. To explain this simply, when a regeneration command is issued, the spindle motor 25 starts to rotate normally, the support base 6 reaches the tips of the lower linear parts 17c and 18c, and the lower lead-in switch 71 detects the position. will be done. When the lower lead-in switch 71 is turned on, the pick-up 4 starts scanning the disk outward, and when the spindle motor reaches a rotational speed of 1800 rpm and the lead-in signal is detected, the pickup 4 starts the track jump and starts reading. When you escape from the inside part, the play track runs, the side information is read, and if there is side information, "SIDE 1" is displayed, and if there is no side information, whichever of the upper and lower lead-in switches is turned ON last. Determines whether it is hot (lead-in SW mode) and displays “SIDE U”. The same is true for top surface playback.
2" or "SIDE L" is displayed.Also, the display is not limited to the TV display, and it is also possible to provide a dedicated display section on the player body.

(G) Effects of the Invention As described above, according to the present invention, if side information is recorded on the disc, the side information itself is displayed, and even if no side information is recorded, the disc surface during playback is displayed. This is done based on the information of whether it is the top side or the bottom side, making it possible to confirm the playback position, improving operability during access operations during program playback and access playback in which playback is performed by moving to a predetermined chapter.

[Brief explanation of drawings]

The drawings all relate to one embodiment of the present invention, and FIG. 1 is a circuit block diagram, FIG. 2 is a perspective view of the pickup moving mechanism, and FIG. 3 is an explanatory diagram of the pickup movement.
FIG. 4 is a display explanatory diagram, and FIG. 5 is a flowchart. 4...Pickup, 6...Support base (Pickup moving means), 9...Disk, 50...
Information analysis section (side information detection means), 53... mechanical determination section (opposing surface detection means), 54... character generation section (display means).

Claims (1)

[Claims] 1. A disk on which information is recorded on the front and back sides, a pick-up that scans the disk to reproduce information, and a pick-up that moves the pick-up so that both sides of the disk can be scanned. means, side information detecting means for detecting side information from reproduced information; opposing surface detecting means for detecting which side of the disk the pick-up faces; side information is recorded on the disk. a display means for displaying the output of the side information detection means when the side information detection means is being recorded; and display means for displaying the output of the facing side information detection means when the opposite side information detection means is not being recorded.