JPH02294287A - Disc rotation controller - Google Patents

Abstract

PURPOSE:To improve responding property by increasing the gain of a rotation control means upon accelerating and/or decelerating a disc. CONSTITUTION:A disc 1 is mounted on a mounting part 15 and is rotated by a motor 2 with a constant linear speed. The tile rotation controller is constituted of a signal regenerating circuit 4, a rotating servo circuit 5, a reference signal generator 6, a buffer amplifier 7, a motor driving circuit 8, a servo control circuit 9 and the like. The servo control circuit 9 indicates acceleration and/or deceleration to the rotating servo circuit 5 and, at the same time, impresses a high level signal on the transistor 14 of the feedback loop of the buffer amplifier 6 to increase the gain of the indication. As a result, the rotation and the stop of the disc 1 may be effected quickly.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a disk rotation control device for rotationally driving a disk.

(Expression) SUMIRAI'S TECHNOLOGY When recording and reproducing information on an information recording medium such as an optical disc, it is advantageous to keep the disc rotating all the time because it allows for faster processing speed than one that rotates only during recording and reproduction.

Therefore, when a disk is inserted into the disk insertion section 5, the disk is immediately rotated and this state is maintained until the disk is ejected.

(C) Problems to be Solved by the Invention Incidentally, the motor that rotationally drives the disk is controlled to always rotate at a predetermined speed (eg, constant linear velocity or constant angular velocity). However, if the rotational state of the disk becomes uncontrollable due to scratches or dust on the disk, feedback cannot be applied to the motor.
Stable rotation control becomes impossible. For this reason, the gain of the rotation control system is reduced to reduce the responsiveness to external disturbances such as scratches and dust on the disk.

However, if the gain of the rotation control system is made small, a lot of time is required to accelerate (or decelerate) the disk when inserting (or ejecting) the disk, which has the disadvantage of lengthening the processing time. Ta.

(2) Means for Solving the Problems The disk rotation control device of the present invention includes a rotating means for rotating a disk on which a signal is recorded, and a voltage applied to the rotating means for accelerating or decelerating the rotation of the disk. The present invention is characterized by comprising a rotation control means for controlling the rotation of the disk, and a control means for increasing the gain of the rotation control means when the rotation of the disk is accelerated or decelerated.

(E) Function According to the present invention, when accelerating or decelerating the rotation of the disk, a large accelerating voltage or decelerating voltage is applied to the motor by increasing the gain of the rotation control means.

(f) Embodiment FIG. 1 is a block diagram showing an embodiment of the present invention. The disc (1) on which the signal has been recorded is inserted into the disc insertion section (1).
5) and rotated by a motor (2) at a constant linear speed. In this state, from disk (1) to big up (3)
), the signal is read by the rotary servo circuit (
5).

On the other hand, the reference signal generator (6) generates a reference signal according to the position of the big absorber (3), and the rotation servo circuit (
5) compares the reference signal and the frame synchronization signal, and if the frame synchronization signal matches the reference signal, the PLL (Pha
Generates an error voltage so that the loop is locked (se Locked Loop).

Then, this error voltage is applied to the motor drive circuit (8) via a resistor (lO) and a buffer amplifier 7), and an appropriate voltage is applied from the motor drive circuit (8) to the motor (2).
given to.

By the above operation, the disk (1) is big up (3
), the rotation is controlled at a constant linear velocity.

However, if you want to insert the disk (1) into the disk insertion section (15) or remove the disk (1) from the disk insertion section (15),
1), the servo control circuit (9) instructs the rotation servo circuit (5) to accelerate (or decelerate). Next, the rotation servo circuit (5) outputs a gradual acceleration voltage (or deceleration voltage) that accelerates (or decelerates) the motor (2) until the PLL is locked (or the disk (1) almost stops). .

Further, the servo control circuit (9) instructs the rotation servo circuit (5) to accelerate (or decelerate), and at the same time, the feedback resistor (I
A high-level signal is applied to the base of the transistor (14) in the line of the resistor (l3) and transistor (14) connected to the feedback loop of the buffer amplifier (6) composed of I) and (l2). Apply.

Therefore, when the disk (1) is inserted into the disk insertion section (15) (or the disk (1) is inserted from the disk insertion section (15))
1), the resistance (lO), (11), (1
2) and (l3) resistance values as R1, R2, R, and R4
Then, the gain of the buffer amplifier (7) is (R2+R3
-+-R2R3/R4)/R. On the other hand, when the PLL is applied, the gain of the buffer amplifier (A) is (
R2+R:I)/R. This allows the disk (1) to be inserted into the disk insertion section (15) (
Alternatively, when the disk (1) is ejected from the disk insertion portion (15), an acceleration voltage (or deceleration voltage) larger than that in the PLL locked state is applied to the motor (2).

Next, the operation will be explained with reference to the timing charts of FIGS. 2 and 3.

The timing chart in FIG.
) The base terminal (A) of the transistor (14), the output terminal (B) of the buffer amplifier (7), and the input terminal of the servo control circuit (9) from when the disk {1} is attached to the PLL until the PLL locks. (Represents the signal state of each point of Cl. When the disk (1) is inserted into the device, at the time point A, the servo control circuit (9) sends a signal (Il2l not shown) to the rotational servo circuit (5) to instruct acceleration. output, transistor (1
4) Apply a high-level signal (A,) to the base of. When the rotation servo circuit (5) receives a signal instructing acceleration, it outputs an acceleration voltage for accelerating the motor (2) to the buffer amplifier (A). At this time, the gain of the buffer amplifier (7) has been switched to (Rz+R3-R2R,/R4)/R+, and the acceleration voltage (B1
) is output to the motor drive circuit (8). disk(
1) starts rotating and reaches a predetermined linear velocity, the rotation servo circuit (5) locks the PLL (at the beginning) and applies a high level signal (C2) to the servo control circuit, and at the same time the acceleration voltage { Stop outputting B, }. When the servo control circuit (9) receives the input of the signal (C2), the transistor (14)
outputs a low level signal (A2) to the buffer amplifier (
7) Switch the gain to (R2+R3)/R+.

The timing chart in Figure 3 shows the signal status at each point <A+, (B), and (C) from the state in which the PLL is locked when the disk (1) is ejected until the rotation of the disk (1) stops. There is.

When the ejection of the disk (1) is instructed, the servo control circuit (9) starts the rotation servo rotation ii'! A signal (not shown) instructing to stop is output to <51, and a high level signal (^1°) is applied to the base of the transistor. When the rotation servo circuit (5) receives a signal instructing stop, it outputs a deceleration voltage to stop the motor (2) to the buffer amplifier (7). At this time, the gain of the buffer amplifier (7) is (R2+R3+R2Rl/R4)/R, 1f! ! 1
The deceleration voltage (B,') according to this gain
is output to the motor drive circuit (7). Disc (1
), and the linear velocity of the disk (1) is reduced to 18 (time point 2), the rotational servo circuit (5) changes the low level signal from the fossa level signal (C,'). (02') and its 1 0 0 m s? &
Stop outputting the deceleration voltage (B1°). When the servo control circuit (9) receives the signal fez゜), the servo control circuit (9)
At 0ms7i, a low level signal (
＾2゜) is output.

(g) Effects of the invention

[Brief explanation of drawings]

1 to 3 are diagrams showing one embodiment of the present invention, in which FIG. 1 is a block diagram, and FIGS. 2 and 3 are timing charts. (1)...Disk, (2)...Motor, (3)...
Big up, (4)...Signal regeneration circuit, (5)...
・Rotary servo circuit, (6)...One reference signal generator, (7
)...Buffer amplifier, (8)...Motor drive circuit, (9)...Servo control circuit.

Claims (1)

[Claims] (1) A rotation means for rotating a disk on which a signal is recorded, a rotation control means for controlling a voltage applied to the rotation means to accelerate or decelerate the rotation of the disk, and a gain of the rotation control means as described above. 1. A disk rotation control device comprising: control means for increasing the rotation speed when accelerating or decelerating the rotation of the disk.