JPH03105766A - Optical disk rotary controller - Google Patents

Abstract

PURPOSE:To draw in a disk in the shortest time even in the presence of difference of inertial mass of disks and dispersion in a spindle motor torque by providing a rotating synchronizing device, accelerating fully the spindle while detecting the rotating speed of a rotation detector close to a prescribed number of revolutions and selecting the torque control by the rotating synchronizing device. CONSTITUTION:The device is provided with a rotating synchronizing detector 12 processing a recording signal from a disk 9 obtained by an optical pickup 12 and extracting a rotating synchronizing signal, a switch device 14 controlling the transfer of the rotating synchronizing signal obtained from the rotating synchronizing detector 12, a rotating speed detector 15 detecting the rotating speed of a spindle motor 10, and a logical arithmetic device 16 controlling a spindle motor driver 13 and the switch device 14 with the rotating speed signal from the rotating synchronizing detector 15. After a disk 9 is fully accelerated close to a prescribed rotating speed while detecting the rotating speed of the disk 9, the control is switched to the torque control from the rotating synchronizing detector 12. Thus, the disk is draw in the shortest time even in the presence of difference of inertial mass of disks and dispersion in a spindle motor torque.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an optical disk rotation control device that minimizes the time it takes for a disk to reach playback speed from a stopped state.

2. Description of the Related Art In recent years, optical discs have become popular due to their large recording capacity and ease of handling, and there are various sizes of discs.

An example of the above-mentioned conventional optical disc rotation control device will be described below with reference to the drawings.

FIG. 2 shows a block diagram of a conventional optical disc rotation control device. In Fig. 2, 1 is an optical disk, 2 is a spindle motor that rotates the optical disk, and 3 is an optical pickup that applies a focus servo and a tracking servo to the optical disk to extract signals recorded on the disk. , 4 is a rotation synchronization detection device that processes the disc reproduction signal obtained from the optical pickup to extract a rotation control signal, 6 is a spindle motor drive device that drives the spindle P motor, and 6 is from the rotation synchronization detection device. a switch device for controlling the transfer of the obtained rotation control signal; 8 a timer device for counting a fixed time for full acceleration of the spindle motor; 7 controlling the spindle motor drive device and the switch device from the signal of the timer device; It is a logic operation device that performs

The operation of the optical disk rotation control device constructed as described above will be explained below.

First, the logical operation device 7 activates the timer device 8 to start the timer, turns off the switch device 6, and simultaneously applies a full acceleration signal to the spindle motor drive device 6 to accelerate the spindle motor 2 by 7μ. When a certain period of time has elapsed, a certain period end signal is sent from the timer device 8 to the logical operation unit @7.
will be forwarded to.

Then, the logical operation device 7 stops applying the funnel acceleration signal to the spindle motor drive device 6, turns on the Nutsch device 6, and detects the υ rotation by the rotation synchronization detection device 4 from the disc playback signal obtained by the optical pickup 3. A control signal is extracted and inputted to the switch device 6, and the spindle motor drive device 6 is controlled by the rotation control signal to draw the disk to a predetermined rotation speed.

Problems to be Solved by the Invention However, in the above structure, since the initial acceleration time is always constant, overshoot may occur with respect to a given rotation speed due to differences in the inertia t of the disks, variations in the torque of the nubindle motor, etc. Otherwise, there is a problem that it takes a long time to draw in due to undershoot. FIG. 3a shows the rotational speed pull-in state of the conventional example. In the case of a disk with a light inertial mass, as shown by the curve a, when full acceleration to t0 occurs for a certain period of time, the rotational speed will rise above the predetermined rotational speed, and then the rotational speed will be pulled down to the predetermined rotational speed by the rotation control signal from the rotation synchronization detection device. It takes a total time t. 1. In the case of a disk with a heavy inertial mass, as shown by the curve b, even if it is fully accelerated to t0 for a certain period of time, it will not reach the specified rotation speed.
After that, a total time t2 is required until the rotational speed is pulled to a predetermined rotational speed by the rotational control signal from the rotational synchronization detection device.

In view of the above-mentioned problems, the present invention provides an optical disk rotation control device that can reach a predetermined rotational speed in the shortest possible time even if there are differences in the inertial masses of the disks or variations in the torque of the Subind P motor. be.

Means for Solving the Problems In order to solve the above problems, the optical disc rotation control device of the present invention includes a spindle motor for rotating an optical disc, and a focus servo and a tracking servo for the optical disc. an optical pickup that extracts a signal recorded on the disc by applying the optical pickup; a rotation synchronization detection device that processes the recording signal of the disc obtained from the optical pickup to extract a rotation synchronization signal; and a spindle motor that drives the spindle motor. a drive device, a switch device that controls the transfer of a rotation control signal obtained from the rotation synchronization detection device, a rotation detection device that detects the rotation speed of the spindle motor, and a rotation speed signal of the rotation detection device that controls the rotation speed of the spindle. This device includes a logic operation device that controls the motor drive device and the switch device.

Effect of the Invention With the above-described configuration, the present invention detects the rotation speed of the disk and fully accelerates the disk until it reaches a predetermined rotation speed, and then switches to rotation control from the rotation synchronization detection device. Even if the spindle motor torque varies, it can be pulled in in the shortest possible time without overshoot or undershoot.

Embodiment Hereinafter, an optical disc rotation control device according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a block diagram of an optical disk rotation control device according to a first embodiment of the present invention. In Fig. 1, 9 is an optical disk, 10 is a spindle motor that rotates the optical disk, 11 is the optical disk, and a focus servo button and a tracking servo are applied to the disk to record information on the disk. 12 is a rotation synchronization detection device that processes the disk recording signal obtained from the optical big adder to extract a rotation synchronization signal; 13 is a spindle-motor drive device that drives the spindle motor; A switch device for controlling the transfer of a rotation control signal obtained from the rotation synchronization detection device; 16 a rotation detection device for detecting the rotation speed of the spindle motor; 16 for driving the spindle motor by the rotation speed signal of the rotation detection device; A logic operation device that controls the device and the switch device.

The operation of the optical disc rotation control device constructed as described above will be explained below with reference to the buttons in FIG. 1 and FIG. 3.

Then, the logical operation device 16 turns off the switch device 14,
A full acceleration signal is applied to the motor drive device 13, and the rotation speed of the spindle motor 10 is detected by the rotation detection device 16 while fully accelerating the spindle motor 10. Then, when it is detected that the rotation speed has reached a predetermined number, full acceleration is stopped, the switch device 14 is turned on, and the rotation synchronization detection device 12 performs multi-rotation control based on the disc playback signal obtained by the optical pickup 11. A signal is extracted and inputted to the switch device 14, and the spindle motor drive device 13 is controlled by the rotation control signal to draw the disk to a predetermined rotation speed. In FIG. 3B, when the inertial mass is light, it takes a total time of t3 to fully accelerate to the rotational speed r0 as shown by the curve C and then to pull the rotational speed to a predetermined rotational speed by the rotational control signal from the rotational synchronization detection device. Furthermore, in the case of a disk with a heavy inertial mass, as shown by the curve d, it takes a total time t4 to reach the predetermined rotational speed.

As described above, according to this embodiment, the rotation detection device is provided,
By fully accelerating the spindle while detecting the rotation speed signal of the rotation detection device until it approaches a predetermined rotation speed, and then switching to rotation control from the rotation synchronization detection device, differences in the inertial mass of the disk and variations in the torque of the Nubindle motor can be avoided. can be drawn in in the shortest possible time without overshoot or undershoot.

Effects of the Invention As described above, the present invention includes a Nubindle motor that rotates an optical disc, an optical pink-up that applies a focus servo button and a tracking servo to the optical disc to extract signals recorded on the disc, and the optical pickup. a rotation synchronization detection device that processes a disk recording signal obtained from the disc to extract a rotation synchronization signal; a spindle motor drive device that drives the spindle motor; and a rotation synchronization detection device that controls transfer of the rotation control signal obtained from the rotation synchronization detection device. By providing a switch device, a rotation detection device that detects the rotation speed of the spindle motor, and a logic operation device that controls the Nupindle motor drive device and the Nuitch device based on the rotation speed signal of the rotation detection device. Even if there are differences in the inertial masses of the disks or variations in the torque of the spindle motor, retraction can be achieved in the shortest possible time without overshoot or undershoot.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an optical disk rotation control device according to a first embodiment of the present invention, FIG. 2 is a block diagram of a conventional optical disk rotation control device, and FIG. 3 is a block diagram of the conventional optical disk rotation control device and the present invention. It is a spindle motor operation diagram. 1, 9... optical disc, 2, 10...
...Spindle motor, 3.11... Optical big annog, 4,12... Rotation synchronization detection device, 6,
13...Spindle motor drive device, 6.14
...- Switch device, 8... Timer device, 7, 16... Logical operation device, 16... Rotation detection device.

Claims (1)

[Claims] A spindle motor that rotates an optical disk, an optical pickup that applies a focus servo and a tracking servo to the optical disk to extract signals recorded on the disk, and a processor that processes the recorded signal of the disk obtained from the optical pickup. A rotation synchronization detection device that extracts a rotation synchronization signal, a spindle motor drive device that drives the spindle motor, a switch device that controls the transfer of a rotation control signal obtained from the rotation synchronization detection device, and a rotation speed of the spindle motor. A rotation detection device for detecting rotation, and a logic operation device for controlling the spindle motor drive device and the switch device based on a rotation speed signal of the rotation detection device, and the logic operation device fully controls the spindle motor drive device from the beginning. When the acceleration signal starts to be applied and the spindle motor reaches close to a predetermined rotation speed, the full acceleration signal to the spindle motor drive device is stopped, and the switch device is turned on to switch to the rotation control signal obtained from the rotation synchronization detection device. An optical disc rotation control device characterized in that: