JP2590911B2 - Optical information recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to optical information for optically recording or reproducing optical information on a card-shaped optical information recording medium (hereinafter referred to as "optical card"). The present invention relates to a recording / reproducing device.

<Prior Art> Conventionally, as this type of optical information recording / reproducing apparatus, there is an optical information recording / reproducing apparatus in which an optical card is reciprocated by one-way driving of a driving unit to record and reproduce optical information on the optical card.

FIG. 3 shows an example of an apparatus of this type, in which a holder 1 provided with a card holding portion for holding an optical card on the lower surface, and a holder 1
And a card feed mechanism 4 for reciprocating the holder 1 with respect to the optical head 3. A guide shaft 5 is provided on the rear side of the holder 1 at right angles to the direction in which the holder moves, and a slide member 6 is supported on the guide shaft 5. The slide member 6 is connected to the card feed mechanism 4.

The card feed mechanism 4 has two support shafts 7, 8 with pulleys 9, 1
The endless belt 11 is stretched between the pulleys 9 and 10 by disposing 0 respectively. A connection pin 12 is provided at an appropriate position of the endless belt 11, and the connection pin 12 is pivotally connected to the slide member 6. A pulley is located below one of the support shafts 8.
A transmission means 11 such as a belt is fixed to the pulley 9.
And a rotary encoder (not shown) for detecting the number of rotations of the motor 14 is connected to the other support shaft 7.

FIG. 4 shows a speed control system of a drive unit 15 including the motor 14.
16 shows a detection speed of the drive unit 15, that is, a frequency-voltage converter 17 for converting the output of the rotary encoder into a voltage, and a subtractor 18 for obtaining a difference voltage between the converted voltage and the speed setting voltage. And a power supply unit 19 that supplies an appropriate gain to the difference voltage and supplies the difference voltage to the drive unit 15.

<Problems to be Solved by the Invention> In the above apparatus example, when the motor 14 is driven in one direction to reciprocate the holder 1, the connecting pin 12 provided on the endless belt 11 is pulled by the pulley in the inversion region of the holder 1. It rotates around 9,10, which appears to the motor 14 as a large change in load torque.

FIG. 5 shows the relationship between the position of the holder 1 and the rotation speed fluctuation of the pulleys 9 and 10. In the figure, A indicates an inversion area of the holder 1, and B indicates a recording / reproducing area. When the holder 1 reaches each inversion area A, the photosensors 20 and 21 disposed at appropriate places detect this. Then, the detection signal S is output.

According to the figure, when the holder 1 enters the reversal area A, the rotation speeds of the pulleys 9 and 10 first increase slightly, then decrease rapidly, and then increase more rapidly to reach the set speed V ₀ .
This speed fluctuation occurs not only in the inversion area A but also in the recording / reproduction area B.
The effect remains strong up to.

By the way, the recording and reproduction of the optical information with respect to the optical card are performed in the recording / reproducing area B, so that the speed fluctuation in the reversal area A poses almost no problem. However, if the influence of the speed fluctuations remains strongly in the recording / reproducing area B, the speed fluctuations ΔV have an adverse effect on the reproduction in which the holder 1 is reciprocated at a particularly high speed, and as a result, the optical head 3 detects a disturbed reproduction signal. Thus, there is a problem that information cannot be reproduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problem, and a novel optical information recording / reproducing apparatus capable of reliably and stably recording / reproducing optical information by suppressing a speed fluctuation in a recording / reproducing area due to an inversion operation. The purpose is to provide.

<Means for Solving the Problems> In order to achieve the above object, according to the present invention, the optical information recording medium is reciprocated relative to the optical head by driving the driving unit in one direction by a speed control system. In an optical information recording / reproducing apparatus for recording or reproducing optical information on / from an optical information recording medium, an inversion detecting section for detecting that the optical information recording medium has reached an inversion area for reciprocating operation from a recording / reproduction area. And a speed correction unit for increasing the power supplied to the drive unit when receiving the detection signal from the inversion detection unit and correcting the speed fluctuation of the optical information recording medium in the recording / reproducing area. .

<Operation> When recording or reproducing optical information on or from an optical information recording medium, the drive section is driven in one direction by a speed control system, thereby causing the optical information recording medium to reciprocate relative to the optical head. When the optical information recording medium reaches the reversal area in this reciprocating operation, the reversal detection section detects this and outputs a detection signal to the speed correction section. When the speed correction unit receives the detection signal, the power supplied to the drive unit is increased, and the speed fluctuation of the optical information recording medium in the recording / reproducing area is corrected to be small.
As a result, the speed in the recording / reproducing area is stabilized, and recording and reproduction of optical information can be performed reliably and stably.

<Embodiment> FIG. 1 shows a speed control system 22 of an optical information recording / reproducing apparatus according to an embodiment of the present invention, which includes a drive unit 15, a frequency-voltage converter 17, a subtractor 18, a speed correction circuit. 23, an adder 24, a power supply unit 19, and the like are included in the configuration.

The drive section 15 uses a motor 14 for driving the card feed mechanism 4 shown in FIG.
Is driven in one direction, the holder 1 reciprocates. The speed of the motor 14 is detected by a rotary encoder (not shown).

The frequency-voltage converter 17 converts the output of the rotary encoder into a voltage, and the subtracter 18 obtains a difference voltage between the converted voltage and the speed setting voltage. This difference voltage is output to the power supply unit 19 as it is when the speed correction circuit 23 does not operate, and is supplied to the drive unit 15 after being given an appropriate gain.

The speed correction circuit 23 operates when the holder 1 reaches the reversal area A in the reciprocating operation, outputs a constant voltage for a fixed period, and is added to the difference voltage by the adder 24.
This added output is output to the power supply unit 19, where it is given an appropriate gain and supplied to the drive unit 15. The fact that the holder 1 has entered the inversion area A from the recording / reproduction area B is detected by the photosensors 20 and 21 disposed at the corresponding positions, and the detection signal is output to the speed correction circuit 23. become.

FIG. 2 shows the relationship between the position of the holder 1 and the rotation speed fluctuation of the pulleys 9 and 10 when the speed correction circuit 23 is operated in the reverse area A.

In each inversion area A, as a result of applying a constant voltage for a fixed time by the speed correction circuit 23, more power is supplied to the drive unit 15 than in normal control. Therefore, when the holder 1 enters the reversal area A from the recording / reproducing area B, the rotation speeds of the pulleys 9 and 10 rapidly increase first, and thereafter the inertia force of the holder 1 largely acts as a load on the motor 14, so that the rotation speed is reduced. the set speed V ₀ drops sharply to the point where slightly below. And at the stage of reaching the recording and reproduction area B from inversion region A, in which the rotational speed is gradually restored rises to the set speed V _0.

According to the drawing, the power applied to the drive unit 15 by the speed correction circuit 23 in the inversion area A is increased, and as a result, the speed reduction curve shown in FIG. The variation ΔV ′ is considerably small. Therefore, with this speed fluctuation ΔV ′, the holder 1
In particular, even during reproduction in which the reciprocating operation is performed at a high speed, the reproduction operation is not adversely affected, and an appropriate reproduction signal is reliably detected by the optical head 3. Moreover, as a result of the speed increase in the reversal area A, the time required for the holder 1 to reciprocate is reduced, and the performance of the apparatus is improved.

<Effect of the Invention> As described above, the present invention detects the optical information recording medium from the recording / reproducing area to the reversal area for reciprocating operation and increases the power applied to the drive unit to increase the power for recording / reproducing. Since the speed fluctuation of the optical information recording medium in the area is corrected, the speed in the recording / reproducing area is stabilized, optical information can be recorded / reproduced reliably and stably, and the round trip time of the optical information recording medium is shortened. Thus, remarkable effects of achieving the object of the invention, such as improvement of the performance of the apparatus, are achieved.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram showing one embodiment of the present invention, FIG. 2 is an explanatory diagram showing a relationship between a position of a holder and a rotation speed fluctuation of a pulley, and FIG. 3 is a diagram showing an internal mechanism of an optical information recording / reproducing apparatus. FIG. 4 is a circuit block diagram showing a conventional speed control system, and FIG. 5 is an explanatory diagram showing a relationship between a position of a holder and a rotation speed fluctuation of a pulley in a conventional system. DESCRIPTION OF SYMBOLS 1 ... Holder, 4 ... Card feed mechanism 14 ... Motor, 15 ... Drive unit 20, 21 ... Photosensor 22 ... Speed control system, 23 ... Speed correction circuit

Claims (2)

(57) [Claims] 1. An optical information recording medium is reciprocated relative to an optical head by driving a driving unit in one direction by a speed control system to record or reproduce optical information on the optical information recording medium. In an optical information recording / reproducing apparatus, an inversion detection unit that detects that the optical information recording medium has reached an inversion area for reciprocating operation from a recording / reproduction area, and when receiving a detection signal from the inversion detection unit, An optical information recording / reproducing apparatus comprising: a speed correction unit for increasing a power applied to the unit to correct a speed variation of the optical information recording medium in the recording / reproducing area. 2. A speed control system comprising: means for detecting the speed of an optical information recording medium; means for converting the detected output into a voltage; and a difference voltage between the converted voltage and a speed setting voltage. 2. The optical information recording / reproducing apparatus according to claim 1, further comprising: means for obtaining the difference voltage; and means for giving a gain to the difference voltage and supplying the difference voltage to a driving unit.