JPH0437498B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an information recording device for recording information such as a video signal on a disc-shaped record carrier.

Conventional structure and problems Concerning the constant linear velocity (hereinafter referred to as CLV) of a recording device, the recording density is constant at each point on the radius of a disc-shaped record carrier (hereinafter referred to as a disk), and the constant angular velocity (hereinafter referred to as CAV),
It has been widely proposed because it increases the amount of information recorded on a single disk.

A conventional example is shown in FIG. 1 and will be explained based on FIG. A disk 1 is held on a turntable 2 and rotationally driven by a turntable motor 3. The recording pickup 4 records information at point a on the disk 1 optically or mechanically. However, if the recording pickup 4 is an optical type, a photosensitive agent such as a resist must be applied onto the disk 1.

The recording pickup 4 is movable in the radial direction of the disk 1 by means of a feeding means 5, and the radial position of the recording pickup 4 is detected by a potentiometer 6 as a voltage V _R . The voltage V _R from the potentiometer 6 increases proportionally as the radial position of the recording pickup 4 moves outward, as shown in FIG. The rotation speed of the turntable motor 3 is determined by a frequency generator (hereinafter referred to as FG).
7, and the F-V converter 8 generates a voltage _V
occurs. This is shown in FIG.

The respective output voltages of the potentiometer 6 and F-V converter 8 are applied to a differential amplifier 9 to create an error voltage _VE . This error voltage V _E passes through the power amplifier 10 and drives the motor 3. At this time, adjust the potentiometers 6 and F so that the linear velocity becomes a predetermined value.
-V converter 8 must be adjusted.

Using such an analog method will improve the accuracy, linearity, temperature stability, etc. of the potentiometer 6.
Also, the temperature stability of the F-V converter 8 becomes a problem, and it is necessary to adjust the characteristics including the temperature characteristics of the potentiometer 6 and the F-V converter 8. Further, in the conventional example, there is no control of the feeding means necessary for recording, and control of the feeding means 5 including the feeding motor is important as well as control of the turntable motor 3.

Purpose of the Invention In view of these points, the present invention controls the motor of the rotating device that rotates the disk and the motor of the feeding means that moves the recording pickup in the radial direction, thereby recording information.
The purpose of this invention is to provide a disc-shaped information recording device that can be used with CLV.

Structure of the Invention In order to achieve the above object, the present invention provides a rotating device for rotationally driving a disk-shaped record carrier, a recording pickup for recording information on the disk-shaped record carrier, and a recording pickup for moving the recording position of the recording pickup. A recording device for recording information such as a video signal and an audio signal on a disk-shaped record carrier, the recording device having a sending means, a scale for detecting a recording position and digitally outputting data, and a scale for detecting the recording position and outputting the data digitally, and the recording position data and linear velocity. a first reference signal generation circuit consisting of a microprocessor that inputs data and performs arithmetic processing; a crystal oscillator; and a programmable counter;
a second reference signal generation circuit which inputs the output of the reference signal generation circuit and performs frequency conversion; the output of the crystal oscillator and the output of the microprocessor are added to a programmable counter; By changing the frequency division ratio of the programmable counter, the frequency of the output signal of the first reference signal generation circuit is changed, and
controlling the motor of the rotating device so as to be synchronized with the output of the second reference signal generating circuit, and controlling the feeding motor of the feeding means so as to be synchronized with the output of the second reference signal generating circuit;
The recording medium is configured to perform recording at a constant linear velocity at any position on the radius of the disc-shaped record carrier.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below based on the drawings. In FIG. 4, a disk 1 is held on a turntable 2 and rotated by a turntable motor 3. As shown in FIG. The recording pickup 4 optically or mechanically records information at point a on the disk. The recording position point a is detected by a digital scale 11, and the digital output from the digital scale 11 is applied to a microprocessor 12. Similarly, the value of the linear velocity V ₀ is digitally applied to the microprocessor 12 from the outside,
The calculation process is as follows.

N=2πR×f ₀ /V ₀ ×M ₁ ×10 ^3Where , R: Recording position (mm) f ₀ : Crystal oscillation frequency (Hz) V ₀ : Linear velocity (m/sec) M ₁ : Turntable motor The digital output N of the _{microprocessor} 12 is applied to the reference signal generation circuit 13. The reference signal generation circuit 13 includes a crystal oscillator 19 as shown in FIG.
and a programmable counter 20. The digital output N of the microprocessor 12 is applied to a programmable counter 20 to change the frequency division ratio to change the frequency of the reference signal. At this time, the oscillation frequency F of the reference signal A is F=M ₁ ×
(RPs). Here, RPS is the rotational speed (Hz) when the turntable motor 3 is locked to the reference signal.

The rotation speed of the turntable motor 3 is detected by the FG7 and applied to the turntable motor control circuit 14, the reference signal A is also applied to the motor control circuit 14, and the output of the motor control circuit 14 drives the motor 3. In this way, the turntable motor 3 is rotationally driven in synchronization with the reference signal A.

The motor control circuit 14 is constructed as shown in FIG. That is, the reference signal A and the FG signal are applied to the phase comparator 21 to generate an output signal according to the phase difference between the two signals, and the filter 2
2 and is applied to the power amplifier 23. The amplified output drives the turntable motor 3.

On the other hand, the reference signal A is also supplied to the feed motor control circuit 15. In order to move the recording pickup 4 according to the rotation of the turntable 2, the number of teeth M ₂ of the FG 17 of the feed motor 16 and the transmission ratio K of the feed stage 18 must be taken into consideration. For this reason, the feed motor control circuit 15
is the turntable motor control circuit 14
It has an extra frequency conversion circuit 24 compared to the above. The reference signal B produced by the frequency conversion circuit 24 is applied together with the FG signal to a phase comparator 25, and the phase comparator 25 generates a signal according to the phase difference. The output of the phase comparator 25 is sent to the filter 2
6. The signal is applied to the feed motor 16 via the power amplifier 27, and moves the recording pickup via the feed stage 18.

With this method, by controlling the feed motor 16 and turntable motor 3, not only can CLV operation during recording be easily achieved, but also the set linear velocity during recording can be easily changed, allowing It is also possible to perform recording by changing the linear velocity within the disc 1.

Furthermore, since the digital scale 11 generally has high precision and often measures the phase distance magnetically or optically, it is possible to measure the phase distance at any position outside the recording range (for example, at the outermost periphery) as shown in FIG. ), and a magnet 29 is attached to a part of the recording pickup 4. When the recording pickup 4 moves to the position of this Hall element 28, the magnet 29
The Hall element 28 undergoes a change due to the action of , and it is appropriate to preset the data R ₀ to the scale based on this change. Furthermore, when the disk 1 is attached to the turntable 2, it may be moved to the outermost periphery, and the scale may be automatically preset by the function of the Hall element 28 in this outermost periphery state.

All of the explanations so far have been based on the configuration in which the recording pick-up 4 moves, but when the recording pick-up 4 is fixed and the turntable 2, turntable 3, and disk 1 are moved, the position on the disk 1 is measured using the digital scale 11. However, it is sufficient to simply move the disk 1, motor 3, etc. using the feed stage 18.

Further, as shown in FIG. 10, it is possible to easily perform both CAV and CLV in one recording device by switching the reference signal A to the external reference signal C using the changeover switch 30.

Effects of the Invention As described above, according to the present invention, there is provided a scale for detecting the radial position of the recording pickup, the digital output from this scale is processed by a microprocessor, and the output of the microprocessor is changed into a frequency. After that, the motor of the rotating device and the motor of the feeding means are controlled using the signal having the frequency as a reference, so that the constant linear velocity (CLV) of the recording device can be easily obtained. Furthermore, since CLV operation is achieved through digital and pulse processing, it is stable in terms of temperature and steady state.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a conventional example, Fig. 2 is a characteristic diagram of a potentiometer used in the conventional example, Fig. 3 is a characteristic diagram of an F-V converter used in the conventional example, and Fig. 4 is a diagram of the present invention. FIG. 5 is a detailed configuration diagram of the reference signal generation circuit, FIG. 6 is a detailed configuration diagram of the turntable motor control circuit, FIG. 7 is a detailed configuration diagram of the feed motor control circuit, and FIG. FIG. 8 is a configuration diagram when using a scale for measuring relative distance, and FIG. 9 is a configuration diagram when CAV/CLV switching is performed. 1... Disc, 3... Turntable motor, 4... Recording pick-up, 5... Feeding means,
7... Frequency generator, 11... Digital scale, 12... Microprocessor, 13... Reference signal generation circuit, 14... Turntable motor control circuit, 15... Feed motor control circuit, 16... Feed Motor, 17... Frequency generator, 19... Crystal oscillator, 20... Programmable counter, 28... Hall element, 29...
Magnet, 30...Switch.

Claims (1)

[Claims] 1. A rotation device that rotationally drives a disc-shaped record carrier;
A recording device for recording information such as a video signal and an audio signal on the disc-shaped record carrier, comprising a recording pickup for recording information on a disc-shaped record carrier, and a sending means for moving the recording position of the recording pickup, A first reference signal generator consisting of a scale that detects a recording position and digitally outputs data, a microprocessor that inputs and processes the recording position data and linear velocity data, a crystal oscillator, and a programmable counter. circuit and
a second reference signal generation circuit that receives the output of the first reference signal generation circuit and performs frequency conversion;
By adding the output of the crystal oscillator and the output of the microprocessor to a programmable counter, and changing the frequency division ratio of the programmable counter depending on the output of the microprocessor, the first
By changing the frequency of the output signal of the reference signal generation circuit,
controlling the motor of the rotating device so as to be synchronized with the output of the first reference signal generation circuit, and controlling the feed motor of the feeding means so as to be synchronized with the output of the second reference signal generation circuit; A disk-shaped information recording device configured to record constant linear velocity at any position on the radius of the disk-shaped record carrier. 2. The scale for detecting the recording position is used as a length measuring device for measuring relative distance, and when the recording position of the recording pickup matches this reference point with an arbitrary point outside the recording range of the disc-shaped record carrier as a reference point, 2. The disc-shaped information recording device according to claim 1, wherein a reference value is input to a length measuring device. 3. The output of the first reference signal generation circuit is configured to be switchable with an external constant angular velocity (CAV) signal, and also enables recording of CAV. disc-shaped information recording device.