JPS58212658A - Method for accessing pickup - Google Patents

Abstract

PURPOSE:To shorten access time, by carrying a pickup roughly up to a prescribed range close to an objective position, and reducing the working amount of rough carrying up to a half of it successivel in the prescribed range. CONSTITUTION:A control circuit 10 consists of an arithmetic unit 101, a feed motor driving voltage generator 102 to rotate a feed motor 4 and move a pickup 2 and a jump signal generator 102 to jump the pickup 2 to an adjacent track. The position of the pickup 2 can be discriminated by inputting positional information from a digital signal processing circuit 16 to the arithmetic unit 101. The pickup 2 is carried by the feed motor 4 for a fixed time T until the objective position is exceeded and then returned in the reverse direction in the period of time of T/2. The pickup 2 is carried for T/4 moreover and, finally, accessed by track jump.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a disc playback device, and more particularly to a pickup access method for cueing a desired song on a music disc.

Due to recent advances in digital technology, PCM (Pulse
With the advancement of code modulation, the digitalization of music discs has become a reality. When a music signal is digitized and recorded, it becomes easy to record information other than music as well. For example, Figure 1A
is a diagram showing the state of the disc, where the hatched areas represent the intervals between songs, and the first, second, and third songs represent areas where music is recorded. Corresponding to A, for example, there is information NB that indicates whether it is between songs or during a song, information C that indicates the song number, and information about the elapsed time from the start of the performance of each song. It is recorded on a disc together with a PCM music signal (hereinafter referred to as main information). Such information is especially essential for optical discs because the recording density is so high that it is impossible to visually distinguish between tracks and between tracks.

Therefore, in a device for playing such discs, it is essential to have a function such as automatically and quickly accessing the pickup to the beginning of a desired song.

SUMMARY OF THE INVENTION An object of the present invention is to provide a pickup access method for quickly and accurately accessing a pickup to a target position in a disc reproducing apparatus in which position information is recorded together with main information as described above.

For this reason, in case of misfire, eA, is a moving means that coarsely feeds the pickup to a predetermined range near the target position, +F9r, when it enters a predetermined range, a signal track is sent to a jumping means, and a pick-up position is set to a position recorded on the disk. The purpose is to shorten access time by providing an identification means for identifying based on information and sequentially halving the amount of Japanese delivery.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a diagram schematically showing a pickup feeding mechanism according to the present invention.

In FIG. 2, the pickup 2 that reads the signal from the disk 1 is given driving force through the gears 5 and 6 connected to the feed motor 4, the worm gear 7, and the rotary shaft 3, and moves along the disk IK (in the left and right directions in the drawing). Moved. In FIG. 2, 8 is a motor for rotating one disk, and 9 is a rotating shaft, but since these are not essential parts of the present invention, a detailed explanation of their operation will be omitted. 10 is a control circuit that controls the feed motor 4 and the pickup 2, and its control method is an important part of the present invention. Figure 3 shows the part related to the non-inventive trap from the air connection diagram of the system in Figure 2. The pickup 2 consists of a portion 2A for detecting signal errors recorded on the disk 1, and a portion 2B for obtaining a track servo error signal for tracing over the signal track of the disk 1. When playing disc 1,
Since the control signal TSW from the control circuit 1o connects the changeover switch 11 to the (A) side, a track servo error signal is supplied to the actuator 13 of the pickup 2 via the amplifier 12 to track one signal track. Further, the track servo error signal is supplied to the feed motor 4 through an adder 14 and 15 amplifiers, and the pickup 2 is controlled to move along the disk by the feed motor 4 based on the track servo error signal. Incidentally, the track servo error signal will not be described in detail, but its characteristics are, as shown in FIG. 4, an electrical signal that corresponds to the displacement from the center of the track.

In FIG. 3, one control circuit 1o includes an arithmetic unit 101 which is the center of control, rotates the feed motor 4, and rotates the pickup 2.
A feed motor drive voltage generator 1o8 for moving the pick 7 and a jump signal generator 10 for jumping the pick 7 to an adjacent track. And so, pickup 2
The position is determined by the position information from the digital signal processing circuit 16 and the arithmetic unit 10. It can be identified by incorporating it into

Feed motor drive voltage generator 10. is 8LF or 81. depending on the direction of movement from the computing device 10°. When receiving the R signal, +7M as shown in FIG. 5(a) or Φ).

Generates -7M positive or negative voltage. The length T over which the voltage is generated varies depending on how much the pickup 2 is fed by the feed motor 4, but it is assumed that the length is indicated by the length of 8LF and SLR.

Selector switch 11 while 8LF and SLR are output.
It is assumed that TSW, which is the 0 control signal, outputs a signal connected to the ←) side. In this case, pickup 2 is the feed motor 4
The track servo loop is cut off to prevent abnormal operation. Jumping signal generator 1
0. corresponds to the jumping direction JPF or JPR, as shown in Figure 6(a).
Or generate a signal like (d). ! -1 to 1=1
．． Since the voltage up to 1,000 A (or -VA) is an acceleration signal in the jumping direction, the moving speed of the pickup 2 is proportional to the time as shown in FIG. 6(b).

1=1. From 1=1. -VA (or +VA) up to this point is a deceleration signal, and similarly, as shown in (b), the speed decreases to 5 and 1. -1. = 1. Then 1 == 1. The moving speed becomes 0 at the point in time. Therefore, the moving distance of Pink Up 2 is as shown in FIG. 6(C). A and tl, so that the moving distance t is equal to the track spacing of the disk.
If set to tl', trunk jumping operation is possible. In this case, it is not even p5 that the changeover switch 11 should be connected to the ←) side.

7 and 8 show the access procedure according to the present invention.
Show examples of flow and movement in action. 7, W, and 8 are examples in which the beginning of a song number (hereinafter referred to as MNR) N is accessed from a point where MNR is smaller than N. In Fig. 7 ■, the pickup 2 is sent by the feed motor 4 for a certain period of time T, and
Check with ■ whether the pick up position is greater than or equal to the target MNR, N, and repeat until MNR≧N. This operation corresponds to the region ACl in FIG. Next, at ■, the pick-up 2 is returned to the opposite direction using the intermediate feed motor 4, and at ■, it is checked whether it is within the range that can be accessed by a jumping operation (hereinafter referred to as a track jump). This part corresponds to AC2 in the m8 diagram. If the answer is NO in ■, use ■ to determine the direction in which the pickup 2 should be sent next, use ■ or - to send the pickup 2 with the intermediate feed motor 4, and use the track jump to access the area in ■. Determine whether or not. This area corresponds to AC3 in FIG. ■But NO
When , the next direction to be sent is determined by 1 and 0, and the pickup 2 is sent by the feed motor 4 between 1 and 0.

In FIG. 8, this corresponds to the area AC4.

In this example, it is assumed that access by track jump is possible within the feed amount of ", and when the operations of ■ and ■、■ Continue.

Figure 2 is an enlarged view of the track interval and the beginning of the target MNR = N. If the movement to ■, 0 leads to point X in Figure 9, then the track jump of ■, O By A
Access to the target position is completed after completing the complete rotation of the arrow C5.

In this example, the moving distance by the motor 4 is not ideally the same moving distance as T, and the positive and negative voltages of +7M also vary, so that the moving distance is not necessarily proportional to time. Therefore, even if the movement of ■ and ■ is performed, the area that can be accessed by track jump may not be entered. The access method shown in FIGS. 10 and 11 according to the present invention improves this point. The example in Figure 7 is Pickup 2
Movement with feed motor 4 1 - Minimum unit movement for stones - 4
0 until MNR changes. The difference is that improvements are made by making judgments and repeating them. In Figure 11, A
The movement distance of C1 to ACa is based on successive life and death, but taking -1 into consideration for the bara two xo t xI # xt t
"m". In Figure 11, the effect of the improvement in this example is visible where X is moved twice.
Since the track jump operation is the same as that shown in FIG. 9, it will be omitted.

12 and 13 show the flow and actual operation of another embodiment of the present invention. In this example, the disadvantage of the example shown in FIG. 7 has been improved by pressing the feed motor 4 to ensure that the target position is always crossed each time the distance of movement is changed. The characteristic of the movement in this example is that it moves twice in AC2 and AC4 in FIG. 16.

FIG. 14 shows still another example of the access method of the present invention, which shows a method of processing after finding the target position by track jump of ◎ and 0 in FIGS. 7, 10, and 12. If you perform an operation that causes the pause after access (PAVSE) state as shown in Figures 7, 10, and 12, a sudden sound will be heard after the PAVSE is released, which may cause emotional damage. Things may make you feel uncomfortable, but
This example aims to improve this point. As shown in Fig. 14, after the AC5 track jump finally accesses the target position avm, the AC/i operation is added for a certain period of time or a certain distance in the direction opposite to the direction of the disk's playback force. 7, 10, and 1.
This can be done after detecting the target position shown in Figure 2.

As explained above (according to the present invention), in a disk drive device in which position information is recorded in addition to main information, by using the access method χ according to the present invention, it is possible to quickly and accurately bring the pickup to the target position. Although the present invention has been explained using the example of finding the beginning of a desired song, it goes without saying that the same process can be performed in the case of accessing an arbitrary time of a desired song.

In addition, in the explanation of the present invention, as an example of a method of moving the pickup, a method in which the pickup is sent by a feed motor will be described.
However, there are no restrictions on the 1:1 type of pickup or the feeding method, and the access method of the present invention can be widely applied.

Furthermore, it goes without saying that access can be made in the same way even if the position information recorded on the disk includes track numbers of signal tracks other than the example shown in FIG.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of positional information other than the main signal recorded on the disc, FIG. 2 is a schematic diagram of a pickup feeding mechanism according to an embodiment of the present invention, and FIG. 5 is a diagram showing the system of FIG. 2. Figure 4 is a diagram showing the error signal for the truck servo, Figure 5 is a diagram showing the driving waveform applied to the moving means for moving the pickup, and Figure 6 is a diagram to explain the jumping operation of the pickup. 7 shows the flow of an example of the access method of the present invention, FIG. 8 shows the progress of the access operation in FIG. 7, and FIG. 9 shows the progress of the jumping action.
Fig. 10 is a flow diagram of another example of the access method of the present invention, Fig. 11 is a flow diagram of the access operation of Fig. 10, and Fig. 12 is a flow diagram of another example of the access method of the present invention. FIG. 13 is a diagram showing the flow of the access shaft punch of FIG. 12. FIGS. 14 and 15 are diagrams showing still other access embodiments of the present invention. 1...Disc 2...Pink up 4...Feed motor 11...Switch switch 13...Pickup actuator 10,...
Arithmetic device (including position identification function) 10, ... Jump signal generator 10, ... Feed motor drive voltage generator 14 ... Adder 16, ... Digital signal processing circuit agent Patent attorney Usui 1) Li , luck 1 figure t 2 figure 5 figure 2 figure (b) degree L/Pe 11 δ figure Ac2'? ' ---j Eight years old, 11 figures, 10 figures? 72 Figure 13 Figure 14 Figure 1 -m= c6' Figure 15

Claims (1)

[Claims] t. A disc playback device in which position information such as between songs, divisions within songs, song numbers, time, etc. is recorded together with main information,
A moving means for moving the pickup, a jumping means for jumping the pickup to an adjacent truck, and an identification means for identifying the position information, and movement of the pickup by the moving means and identification of the pickup position by the identification means. After the pickup position approaches a predetermined range of the target position, the jump by the jump means and the position identification by the identification means are repeated to access the target position. Access method. 2. Repeating the movement of the pickup by the moving means and the identification of the position by the identifying means until the pickup exceeds the target position, and when the pickup exceeds the target position, the moving distance of the moving means is sequentially halved to reach the target position. i, after completing the movement of the minimum movement unit of the movement means,
2. The pickup access method according to claim 1, wherein said jumping means moves said pickup to a target position. 3. Movement of the minimum movement unit of the movement means. 3. The pickup access method according to claim 2, wherein the pickup is repeatedly accessed by j% in the moving direction of the pickup until the target position is exceeded. 4. Moving the pickup by the moving means and identifying the position by the identifying means in the moving direction of the pickup until the pickup exceeds the target position, and then moving the pickup by halving the moving distance of the moving means. The movement is carried out in the direction of movement until the target position is exceeded, and then the movement distance of the moving means is halved and the same movement is performed, and when the pickup position approaches within a predetermined range, the pickup position is moved to the target position using the jumping means. 2. The pickup access system according to claim 1, wherein the pickup is characterized by: 5. After accessing the target position, the disc is returned for a certain period of time or a certain distance in the opposite direction to the playback direction of the disc.
Pickup access method described in section.