JPS63117376A - Control system for drive displacing actuator for recording and reproducing element - Google Patents

Abstract

PURPOSE:To prevent an actuator from being displaced due to a disturbance at the time of recording by compensating the phase of the output signal of a comparator at the time of a recording mode, thereafter, negative feeding back to the actuator and maintaining the posture of the actuator at the time of the recording mode. CONSTITUTION:At the time of recording, the actuator is fixed to a position where the output signal of the comparator COMP in a closed loop is set to zero according to the operation of a negative feedback circuit of the closed loop such as the movable part 8 of the actuator ACT, a sensor 8 for generating a signal corresponding to the displacement of the actuator, the voltage transforming circuit SEC of a sensor output signal, the comparator COMP and a differentiation circuit DFC, an addition circuit ADD1, the fixed contact R of a change over switch SW3, the movable contact v thereof, an actuator drive amplifier ADA, the fixed part 7 of the actuator ACT and the movable part 6 of the actuator ACT. Thereby, when a recording and reproducing device is brought into recording mode, the recording posture of a magnetic head H can be set to a desired one.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a control system for a drive displacement actuator for a recording/reproducing element.

(Prior Art) In recent years, as the demand for high-density recording on rotating recording media has increased, the recording marks sequentially formed on the rotating recording medium during recording have been reduced to extremely minute recording marks, for example, several microns in size. It has become desirable to form recording traces at intervals, and in order to be able to reproduce recorded signals well from recording traces with minute recording trace intervals as described above during reproduction, tracking control has become necessary. Under this method, the reproducing element is made to correctly track the sequential recording traces, and the tracking control method is as follows:
A method that uses tracking reference signals recorded in recording traces on both sides of the recording trace being traced by the reproducing element is generally adopted.

(Problems to be Solved by the Invention) The actuators provided in the above-mentioned tracking control system include those in which a center support with small stiffness (high compliance) is used as a component, or one in which a rotation axis is used as a component. A structure that can be freely rotated is advantageous in that the dynamic range of the tracking control system can be widened.

However, il! A recording element used to sequentially record traces at very fine trace intervals on a rotating recording medium during recording, and a recording element used to sequentially form records on a rotating recording medium under tracking control during playback mode. In a recording and reproducing device that uses a recording and reproducing element as a constituent element, the recording and reproducing element also serves as a reproducing element that is driven and displaced by an actuator provided in the tracking control system so that the recording and reproducing element can be accurately tracked. The actuator to which the is attached is one that uses a center support with small stiffness (large compliance) as a component as described above, or one that is configured to be rotatable by a rotation axis. If the tracking control system has a wide dynamic range, the actuator is likely to be displaced by disturbances during recording, which tends to cause disturbances in the interval between recording marks recorded on the rotating recording medium by the recording/reproducing element.

The above problem can be solved by using an actuator equipped with a central support with large stiffness as the actuator to which the recording/reproducing element is attached, but in this case, of course, the movement of the actuator As the mechanical impedance increases, large amounts of power are required to drive the actuator, which reduces efficiency. In addition, linearity between input and output deteriorates, and the sharpness of resonance increases, resulting in damping. Problems arise, such as making it difficult.

(Means for Solving the Problems) The present invention provides a method for driving and displacing the recording/reproducing element in a closed-loop tracking control system using a tracking reference signal read from the recording medium by the recording/reproducing element during the reproduction mode. an actuator, a sensor for generating a signal corresponding to the displacement of the actuator, a comparator for comparing the signal voltage generated by the sensor with a reference signal voltage, and an output signal of the comparator in a recording mode. A control method for an actuator for driving displacement of a recording/reproducing element, in which negative feedback is given to the actuator after phase compensation is applied to the actuator to maintain the posture of the actuator in the recording mode, and the aforementioned driving displacement of the recording/reproducing element. The present invention solves the conventional problems by providing a control method for an actuator for driving displacement of a recording and reproducing element, in which the output signal of the comparator described above is fed back to the transfer motor after phase compensation in the reproducing mode. It is resolved.

(Example) Hereinafter, specific details of the control system for the drive displacement actuator of the recording/reproducing element of the present invention will be explained in detail with reference to the accompanying drawings. FIG. 1 is a block diagram of an embodiment of a control system for a drive displacement actuator of a recording/reproducing element according to the present invention, and the embodiment shown in FIG. A magnetic recording medium MC is used, a magnetic head H is used as a recording/reproducing element, and an actuator ACT is a movable part that is driven around a rotation axis P according to a tracking control signal. It is assumed that a configuration with the following is used.

The above-mentioned rotating magnetic recording medium MC is rotated at a predetermined number of rotations, that is, at a constant rotation rate that is in an integer ratio with the period of a reference synchronization signal, under rotation control by a rotation control circuit of a drive motor (not shown). Drive motor M that rotates in cycles
It is driven and rotated by d. 1 is a rotating shaft of a drive motor Md.

Mf is a transfer motor, the rotating shaft 2 of this transfer motor Mf is coupled to the input shaft of a reducer 3, and the output shaft of the reducer 3 is coupled to a feed screw 4. . A transfer body FA to which an actuator ACT is attached is meshed with the feed screw 4, and when the feed screw 4 is rotationally driven, the transfer body FA has its guide surface 5 as shown in the figure. Depending on the recording/reproducing mode, the rotating magnetic recording medium MC may be continuously transported in a direction parallel to the direction in which the generatrix of the rotating magnetic recording medium MC rotates as the feed screw 4 rotates while being guided by a guide member that is not However, the transfer body FA, which is transferred as described above according to the rotation of the transfer motor Mf, is thereby transferred to the transfer body FA.
The magnetic head H, which is driven and displaced by the actuator ACT attached to the rotary magnetic recording medium MC, is also transferred onto the generatrix of the rotating magnetic recording medium MC.

The actuator ACT is composed of a movable part 6 that is rotationally driven around the rotation axis P, and a fixed drive part 7 that drives the movable part. A sensor (position detection sensor or angle detection sensor) 8 that generates a signal corresponding to the displacement of the actuator is provided at a position separated from the section 6 by a small distance.

The output signal of the sensor 8 that generates a signal corresponding to the displacement of the actuator is sent to a voltage conversion circuit SE for the sensor output signal.
It is converted into a voltage Es by C and supplied to the inverting input terminal of the comparator COMF and the differentiating circuit DFC. Comparator G
The reference voltage Er is supplied to the non-inverting input terminal of OMP, and the voltage (Er-Es) of the difference between the output voltage Es of the voltage conversion circuit SEC and the reference voltage Er of the sensor output signal is output from the comparator COMP. is output.

SWI to SW3 are such that when the recording/reproducing device is in the recording mode, the movable contact V is switched to the fixed contact R side, and when the recording/reproducing device is in the playback mode, the movable contact ■ is switched to the fixed contact P side. It is a changeover switch, and also an ADD
I and ADD2 are adder circuits.

ADA is an actuator drive amplifier, PrA is a preamplifier, TSC is a tracking control circuit, PCI, PO2 is a phase compensation circuit, FMDC is a transfer motor rotation control circuit,
FDA is a transfer motor drive amplifier, and RA is a recording amplifier.

This is because when the recording/reproducing apparatus is in the recording mode, the movable contacts V of each of the changeover switches SW1 to SW3 are switched to the fixed contacts R side.

Addition circuit ADD adds the FM signal obtained by frequency modulating the composite video signal to be recorded and the tracking reference signal.
The recording signal obtained by the addition in step 2 is amplified by the recording amplifier RA and then supplied to the magnetic head H via the fixed contact R and the movable contact V of the changeover switch SWI.

In addition, the output signal of the transfer motor rotation control circuit FMDC is connected to the fixed contact R and the movable contact V in the changeover switch SWI.
is amplified by the transfer motor drive amplifier FDA and supplied to the transfer motor Mf, thereby rotating the transfer motor Mf, which rotates the output shaft 4 of the reducer 3 to keep the transfer object FA constant. transported at a speed of

The output signal of the sensor 8 that generates a signal corresponding to the displacement of the actuator provided facing the movable part 6 of the actuator ACT attached to the transfer body FA is as follows.
The voltage Es is converted by the voltage conversion circuit SEC of the sensor output signal.
and is supplied to the inverting input terminal of the comparator GOMP and the differentiating circuit DFC.

The comparator GOMP, whose non-inverting input terminal is supplied with the reference voltage Er, outputs a voltage (E
r Es) is output and supplied to the adder circuit ADD2, where it is added to the output signal of the differential circuit DFC, and then passed through the fixed contact R and movable contact V of the changeover switch SW3 to the actuator drive amplifier A.
The signal is supplied to DA, amplified there, and then supplied to the fixed part 7 of the actuator ACT, thereby driving and displacing the movable part 6 of the actuator ACT.

Thereby, the movable part 6 of the actuator ACT → the sensor 8 that generates a signal corresponding to the displacement of the actuator →
Sensor output signal voltage conversion circuit SEC → comparator COMP
and a closed loop negative feedback circuit such as the differential circuit DFC→addition circuit ADDI→fixed contact R of changeover switch SW3→movable contact V→actuator drive amplifier ADA→fixed part 7 of actuator ACT→movable part 6 of actuator ACT. For this purpose, the movable part 6 of the actuator ACT is fixed in a position such that the output signal of the comparator GOMP in the closed loop described above is brought to zero by the operation of the negative feedback loop described above.

Therefore, by appropriately determining the reference voltage Er to be supplied to the non-inverting input terminal of the comparator GOMP, so that the recording state of the magnetic head H is in a predetermined state when the recording/reproducing apparatus is set to the recording mode. , it is possible to set the recording state of the magnetic head H as desired when the recording/reproducing apparatus is in the recording mode.

In the case where the actuator ACT provided in the closed-loop negative feedback circuit described above is of a configuration in which it is pivotally supported by the rotation axis P, the characteristics of the actuator itself and its resistance to disturbance are shown in FIG. The following is an explanation with reference to the block diagram of a).

Generally, an actuator used in a tracking control system has a sufficiently small electrical time constant compared to its mechanical time constant, so its block diagram is shown in Figure 2 (a). expressed.

In Figure 2 (a), Ki is the voltage-current conversion constant, Kt
is the torque constant, J is the rotational inertia, D is the viscous resistance, ΔT is the disturbance, E(S) is the input voltage, and θ(S) is the displacement.

Since the 7-cut unit that is supported by the rotation axis P is a linear system, the displacement due to a step-like disturbance is ψ from equation (2, 1), but in reality, due to the presence of friction, the displacement is Even if it does not become ψ, it will be significantly displaced in response to disturbances, so depending on the recording/reproducing element attached to the actuator with such characteristics, recording will be performed in a constant state during recording mode. It is not possible.

On the other hand, an actuator that is supported by one rotation axis P does not have compliance in its support mechanism, so its mechanical system essentially has no first-order resonance, and therefore has -order resonance. Also, since the movement of the movable parts can be restricted to one dimension, if movement in unnecessary directions can be suppressed, the dynamic range of the tracking control system can be efficiently widened. In this respect, it is suitable as an actuator during playback.

FIG. 2(b) is a block diagram of the actuator when the posture is maintained using a position sensor, where θ is the displacement-voltage conversion sensitivity of the position sensor, and K
p is the gain of the error amplifier.

Then, by rearranging the block diagram in FIG. 2(b) and finding the displacement θ(S) with respect to the input voltage E(S), we get:
The primary actuator in the configuration supported by the rotation axis P has a natural angular frequency ωn isometrically shown in equation (2, 2), and is shown in equation (2, 3). It can be seen that the actuator operates as a secondary system actuator having a damping coefficient ζ such as

However, since the system of the actuator in the state shown in the block diagram of FIG. 2(b) is unstable, a feedback compensation circuit as shown in the block diagram of FIG. Aim for stabilization. Of course, the system described above may be stabilized by, for example, feeding back the output of a tachometer provided separately to the actuator, or by performing series compensation, for example.

When the system is stabilized by a feedback compensation circuit as shown in the block diagram shown in Figure 3,
Since the displacement θ(S) with respect to the disturbance ΔT is given by equation (3), it can be seen that the influence of the disturbance can be greatly reduced by increasing the loop gain of the attitude control system of the actuator.

That is, an actuator having a configuration in which it is pivotally supported by rotation al'1llF is connected to the movable part 6 of the actuator ACT → the sensor 8 that generates a signal corresponding to the displacement of the actuator → the sensor output, as in the embodiment shown in the first diagram. Signal voltage conversion circuit SEC → comparator COMP and differentiator circuit DFC → addition circuit ADD1 → fixed contact R of changeover switch SW3 → movable contact V → actuator drive amplifier A
The actuator ACT is supported with great stiffness by providing it in a stabilized closed-loop negative feedback circuit such as DA → fixed part 7 of actuator ACT → movable part 6 of actuator ACT, and
It can function as an actuator equivalent to a one-dimensional drive actuator in a well-damped state, and according to the control method of the drive displacement actuator of the recording/reproducing element of the present invention shown in FIG. In the mode, the movable part 6 of the actuator ACT is fixed at a position where the output signal of the comparator GOMP in the closed loop becomes zero due to the operation of the negative feedback loop described above, and is not affected by external disturbances. It is also possible to prevent it from being displaced.

Next, when the recording and reproducing apparatus is in the reproducing mode, the movable contacts V of each of the changeover switches SWI to SW3
is switched to the fixed contact P side, so the magnetic head H
The reproduced signal is supplied to the preamplifier PrA via the movable contact V and fixed contact P of the changeover switch SWI.

The output signal from the preamplifier PrA is sent to the reproduction signal processing circuit P.
After receiving the necessary signal processing in the SD, it is sent to the monitor receiver MT.
Also, the output signal from the preamplifier PrA is supplied to the tracking control circuit TSC, and the output signal from the tracking control circuit TSC is supplied to the phase compensation circuit PCI.
After the phase is compensated by
Supplied to DA.

The output signal of the actuator drive amplifier ADA is supplied to the fixed part 7 of the actuator ACT, so that the movable part 6 of the actuator ACT drives and displaces the magnetic head H. So, magnetic head H → movable contact V of changeover switch SWI → fixed contact P → preamplifier PrA → tracking control circuit TSC → phase compensation circuit PC1 → fixed contact P of changeover switch SW3 → movable contact V → actuator drive amplifier ADA → Actuator ACT fixing part 7
The magnetic head H is tracked by a closed-loop tracking control system such as → movable part 6 of actuator ACT → magnetic head H → so as to correctly track the sequential recording traces of the rotating magnetic recording medium MC.

On the other hand, actuator A attached to transport body FA
The output signal of the sensor 8, which generates a signal corresponding to the displacement of the actuator provided facing the movable part 6 of the CT, is converted into a voltage E3 by the sensor output signal voltage conversion circuit SEC, and the voltage E3 is applied to the comparator GOMP. It is supplied to the inverting input terminal and the differential circuit DFC.

Since the reference voltage Er is supplied to the non-inverting input terminal of the comparator COMP, the output voltage E of the voltage conversion circuit SEC of the sensor output signal is output from the comparator C○MP.
The voltage difference (Er-Es) between s and the reference voltage Er is output, and the voltage difference (Er-Es) is applied to the phase compensation circuit PC2.
After phase compensation is performed by do.

Thereby, the movable part 6 of the actuator ACT → the sensor 8 that generates a signal corresponding to the displacement of the actuator →
Sensor output signal voltage conversion circuit SEC → comparator COMP
→ Phase compensation circuit PC2 → Fixed contact P in changeover switch SW2 → Movable contact V → Transfer motor drive amplifier FD
A→Transfer motor Mf→Reducer 3→Feed screw 4→Transfer body FA→Movable part 6 of actuator ACT→The closed loop of the transfer body FA causes the output voltage of the comparator GOMP to be in a zero state. They are transported.

In the explanation so far, the drive motor rotates at a predetermined rotational speed, that is, at a constant rotation period that is an integer ratio with the period of the reference synchronization signal, under rotation control by the rotation control circuit of the drive motor (not shown). The magnetic head H performs recording and reproduction on the rotating magnetic recording medium MC, which is driven and rotated by the driving motor Md.
In this example, the rotation shaft 2 of the transfer motor Mf is connected to the output shaft of the reducer 3, which is connected to the input shaft. As the feed screw 4 rotates, the guide surface 5 of the transfer body FA, which is meshed with the feed screw 4 that is meshed with the feed screw 4, moves parallel to the direction in which the generatrix of the rotating magnetic recording medium MC extends while being guided by a guide member (not shown). An embodiment will be described in which frame-by-frame recording is performed by intermittently being transferred in the direction of

Now, in frame-by-frame recording of a composite video signal, the composite video signal to be recorded is recorded in the recording trace of each revolution of the rotating magnetic recording medium during a predetermined period of a predetermined integral multiple of the vertical scanning period. However, in the frame-by-frame recording of composite video signals, the form of the recording traces to be formed on the rotating magnetic recording medium is as follows: Rather than the recording trace drawn on the medium being continuous, each one of the rotating magnetic recording media
It is advantageous for the recording traces of each revolution to be independent closed circles when a composite video signal recorded on a single revolution magnetic recording medium is to be reproduced as a still image. As mentioned above, in order to make the recording traces of each rotation of the rotating magnetic recording medium into independent closed circles, the recording element is intermittently stepped in a direction approximately perpendicular to the recording traces. Conventionally, the most common intermittent stepping mechanism for intermittently stepping the recording element uses a pulse motor, rotary solenoid, linear motor, etc. as a drive source. had been adopted.

However, with a pulse motor as the drive source,
In addition to requiring a large amount of power to drive, there were other problems such as hunting during step motion and large mechanical noise during motion, and the cost was high. It cannot be used as an intermittent stepping mechanism for small and lightweight devices such as electronic cameras, and rotary solenoids and near motors have almost the same problems as those already mentioned for pulse motors. Because of this, it is unsuitable as a drive source for an intermittent stepping mechanism of a device such as an electronic camera that is required to be small and lightweight.

In particular, when performing high-density recording and playback, the interval between recording traces is on the order of microns, but with the intermittent stepping mechanism using the pulse motor, rotary solenoid, or near motor described above, hunting and repeat errors that occur during stepping operations can be avoided. In some mechanisms, positioning on the order of seven microns is difficult due to the occurrence of stop position errors of the recording and reproducing elements due to backlash.

In order to improve the above-mentioned point, the applicant company first developed a system in which the composite video signal to be recorded is recorded in the recording trace of each rotation of the rotating magnetic recording medium by an integer of its multiplex scanning period. The recording/reproducing element is intermittently stepped in a direction approximately perpendicular to the direction in which a recording trace extends on a rotating magnetic recording medium that is driven and rotated at a predetermined rotation speed so that data can be recorded at times of a predetermined length. In order to achieve this, a DC motor, a rotational phase detector that detects the rotational phase of the DC motor, a reduction mechanism that reduces the rotational speed of the DC motor, and a rotational motion of the output shaft of the reduction mechanism that converts it into linear movement. As a control method for the intermittent transfer mechanism of the recording/reproducing element, which is equipped with a mechanism for recording and reproducing, the recording mode of the composite video signal is operated to be a frame recording mode, and the composite video signal is recorded frame-by-frame on a rotating magnetic recording medium. When this is carried out, the recording element is rapidly and intermittently advanced at predetermined intervals by the intermittent stepping mechanism before and/or after the frame recording period. Further, the stop position of the recording element during the intermittent stepping operation is regulated by controlling the rotational state of the DC motor using a signal indicating the rotational phase of the motor shaft of the DC motor. (Refer to Japanese Unexamined Patent Publication No. 173984/1984)
However, the above-mentioned existing proposal is limited to the entire control system, that is, the reduction mechanism that reduces the rotational speed of the DC motor, and the rotation of the output shaft of the reduction mechanism. Since the actuator transport mechanism that converts motion into linear motion and the actuator that transports the recording/reproducing element are in an open loop, the recording conditions are different in terms of time and temperature like in frame-by-frame recording. If the number of frames is often different for each frame, expansion and contraction due to temperature of the substrate and mechanical parts of the magnetic recording medium may cause the intervals between the recording traces formed in parallel on the magnetic recording medium to be constant. Since there was a problem that it was cumbersome to record in the same way, the applicant company previously decided to change the recording position in the frame shot recording as described in the patent application specification of Japanese Patent Application No. 120851/1983. In a control method, when recording traces of information signals are formed on a magnetic recording medium in parallel at a predetermined interval between recording traces, information from adjacent recording traces in the recording traces recorded in parallel on the magnetic recording medium is used. We have proposed a recording position control method for magnetic recording media that uses the amount of crosstalk in a signal as distance information from adjacent recording traces to control the recording position of a new recording trace to be recorded, thereby solving the problems described above. First, we will explain the case where the control method of the drive displacement actuator of the recording/reproducing element of the present invention is applied to the recording position control method in the already proposed frame-by-frame recording as described above. do.

FIG. 4 is a block diagram when the control method of the drive displacement actuator of the recording/reproducing element of the present invention is applied to the recording position control method in the already proposed frame-by-frame recording as described above. SG is a composite video signal source targeted for recording, and OCT is a control circuit,
RG is the recording signal gate, PAG is the reproduction signal gate, IN
V is an inverter, and the opening and closing of the recording signal gate RG and the reproduction signal gate FAG are controlled by a gate signal sent from the control circuit OCT.

The gate signal (m) for opening and closing the recording signal gate RG is shown in (m) in FIG. 5, and the gate signal (n) for opening and closing the reproduction signal gate hPAG is
) is (n) in FIG. 5 when the polarity of the gate signal (m) for opening and closing the recording signal gate RG shown in (n) in FIG. 5 has been inverted by the inverter INV.
Therefore, the opening/closing control states of the recording signal gate RG and the reproduction signal gate PAG are reversed to each other.

Since the composite video signal generated by the signal composite video signal source SG is given to the recording signal gate RG, when the recording signal gate RG is open, the composite video signal from the composite video signal source SG is sent to the recording signal gate RG. is supplied to the magnetic head H and recorded on the rotating magnetic recording medium MC.

Further, when the reproduction gate PAG is open, a composite video signal is reproduced by the magnetic head H.

The signal is supplied to the regenerated yarn PAG, subjected to necessary signal processing in the reproducing system PAG, and then supplied to the monitor receiver MTV so that one image can be reproduced. A signal detection operation required for recording position control can also be performed.

The composite video signal source SG described above may have any configuration, but in the following example, the synchronization signal that serves as a reference for the operation of the device is transmitted from the composite video signal source SG to the control circuit. It is said that it is given to OCT,
Further, the signal source SG of the composite video signal is provided with a generator of a control signal for controlling the recording position in the rotating magnetic recording medium, and when the composite video signal is recorded on the rotating magnetic recording medium MC, Control signals for controlling the recording position in can also be recorded on the rotating magnetic recording medium MC.

Now, in the circuit arrangement shown in FIG. 4, since the control signal for controlling the recording position in the rotating magnetic recording medium MC is read out as a crosstalk component from the adjacent recording trace, it is necessary to read out the control signal for controlling the recording position in the rotating magnetic recording medium MC. The control signal for controlling the recording position recorded on the MC is a low frequency signal that can be read by the magnetic head H located at an adjacent recording track.

The control signal for controlling the recording position in the rotating magnetic recording medium MC described above is frequency multiplexed with the composite video signal that is recorded and reproduced by the rotating magnetic recording medium MC, and is recorded on the rotating magnetic recording medium MC. be done.

When the control signal for controlling the recording position in the above-mentioned rotating magnetic recording medium MC is recorded in the horizontal blanking period of the composite video signal using, for example, a signal of a specific single frequency. The composite video signal is produced using a recording mode in which the recording position of the horizontal synchronization signal in the composite video signal is aligned in a direction perpendicular to the direction in which the recording traces extend with respect to sequential recording traces that are recorded in parallel. The recording position of the control signal for controlling the recording position in the adjacent recording traces is as shown by the square mark in Figure 6. A control signal for controlling the recording position on the rotating magnetic recording medium MC is provided for every other horizontal blanking period in the horizontal blanking periods that are continuous on the time axis so that the recording position does not match. It will be done. Incidentally, in FIG. 6, the white corner mark indicates the recording position in the horizontal blanking period in which no control signal for controlling the recording position in the rotating magnetic recording medium MC is recorded.

Furthermore, the control signals for controlling the recording position in the rotating magnetic recording medium MC described above may be recorded in the form of a continuous signal by being frequency-multiplexed into the composite video signal. Control signals for two or more possible types of recording position control are sequentially and alternately recorded on successive recording traces.

The operation unit oP is provided with an operation switch for instructing various operation modes of recording, recording, and playback, and in response to the operation of the operation switch, the control circuit OCT:
Required control signals are given to each component of the device so that each component of the device can perform a predetermined operation.

In the operating section OP shown in FIG. 4, only the operating switch S1 is shown, which is operated when performing a frame-by-frame shooting operation that will be described later.

As the control circuit OCT, one configured to include, for example, a microcomputer can be used.

The rotating magnetic recording medium MC is driven and rotated at a predetermined number of rotations by a driving motor Md.
The number of rotations of the drive motor Md (the number of rotations of the drive motor Md) is set to have a specific relationship with the vertical scanning period of the composite video signal to be recorded on the rotating magnetic recording medium MC. Automatically controlled by motor servo circuit.

That is, the drive motor servo circuit compares the phase of the output pulse from the pulse generator indicating the rotational phase of the rotation shaft of the drive motor Md with the vertical synchronization pulse supplied from the control circuit, and A rotating magnetic recording medium MC driven and rotated by a rotary magnetic recording medium MC records a composite video signal corresponding to a vertical scanning period of a predetermined number of g in the composite video signal to be recorded, with the correct recording phase within one circumference of the composite video signal. It is automatically controlled to rotate at a rotational speed and rotational phase that can be recorded.

The rotating magnetic recording medium MC is configured so that, when the vertical scanning period of the composite video signal to be recorded on it is 1760 seconds, for example, a composite video signal with one vertical scanning period is recorded for every rotation of the rotating magnetic recording medium MC. 36 per minute when done
For example, when a composite video signal of two vertical scanning periods is to be recorded for each rotation of the magnetic recording medium MC, the rotation is performed at 1800 rotations per minute.

Further, the rotating magnetic recording medium MC is located on its specific generatrix (
In the case of a disc, the horizontal blanking period in the composite video signal will be recorded on the specific rear element.

Its rotational phase is controlled.

During recording, a magnetic head H used for recording recording signals on a rotating magnetic recording medium MC driven and rotated at a predetermined rotational speed and rotational phase by a driving motor Md is moved by a transport mechanism to a rotating magnetic recording medium MC during recording. By being intermittently transported along a specific straight path on the recording surface of the rotating magnetic recording medium MC, closed circular recording traces are intermittently formed on the rotating magnetic recording medium MC.

In FIG. 4, 1Mf is a transfer motor.

As the transfer motor Mf, a motor that can be controlled to perform forward and reverse rotation, for example, a DC motor, is used. A motor shaft (rotating shaft) 2 of the transfer motor Mf is connected to an input shaft of a speed reducer 3 and provides power thereto.

A feed screw 4 is fixed to the output shaft of the reducer 3, and this feed screw 4 allows the rotational speed of the transfer motor Mf to match the speed of the reducer 3.
rotates at a rotational speed reduced by A screw hole provided in the transfer body FA is screwed into the feed screw 4,
Further, the guide surface 5 of the transfer body FA is guided by a guide portion (not shown).

Therefore, when the transfer motor Mf rotates, the transfer body FA is guided by the guide surface 5 in the guide section and is transferred by the feed screw 4. There is an actuator AC on the transport body FA.
A magnetic head H is fixed to the actuator ACT via a cantilever.

The transfer motor Mf is intermittently driven by an intermittent drive circuit (not shown) that operates under the control of a control circuit OCT, so that the magnetic head H is moved over the rotating magnetic recording medium MC. It is moved intermittently at predetermined intervals.

In FIG. 4, LPFI is a low-pass filter, and this low-pass filter LPFI extracts the signal component of the control signal for controlling the recording position in the rotating magnetic recording medium MC from the output signal of the recycled yarn PBA. and convert it to converter PvC
supply to. The converter PvC converts the voltage into a voltage proportional to the signal amount of the control signal for controlling the recording position in the rotating magnetic recording medium MC, and supplies the voltage to the sample and hold circuit SH1.

The sample hold circuit SHI is a control circuit OCT.
The converter PvC is controlled to sample and hold the voltage supplied from the converter PvC at the timing shown in FIG. 5(g). The output signal from the sample hold circuit SHI described above is sent to the comparator COM.
A displacement reference voltage is supplied to the comparator COM Pa as a comparison signal from a displacement reference voltage source Era.

Now, when recording traces of information signals on a rotating magnetic recording medium in parallel with a predetermined interval between recording traces, information signals from adjacent recording traces among the recording traces recorded in parallel on the rotating magnetic recording medium are generated. In a recording position control method for a rotating magnetic recording medium in which the recording position of a new recording trace to be recorded is controlled using the amount of crosstalk from an adjacent recording trace as distance information from an adjacent recording trace, the displacement reference voltage source described above is used. The magnitude of the displacement reference voltage to be applied from Era to the comparator C0MPa is determined as follows.

That is, when it is assumed that a control signal for controlling the recording position is recorded in each record trace that is sequentially formed on the rotating magnetic recording medium MC while maintaining a regular predetermined record trace interval. , the magnetic head H moves over one of the recording traces, for example, the nth recording trace shown in FIG.
is correctly traced, the control signal for recording position control recorded in the (n-1)th recording trace adjacent to the nth recording trace is read as crosstalk by the magnetic head H. The signal is transferred from the above-mentioned reproduction system PBA → low pass filter LPFI → converter PvC → sample hold circuit SH
The voltage value of the signal supplied from the sample-and-hold circuit SHI to the comparator COM P a via the circuit I → and the voltage value of the displacement reference voltage supplied to the comparator COM P a from the displacement reference voltage source Era are The displacement reference voltage to be supplied from the displacement reference voltage source Era to the comparator COM Pa is determined so that they are the same.

Therefore, the above-mentioned comparator COM P a outputs an error signal between the voltage based on the crosstalk amount of the control signal for controlling the recording position in the adjacent recording trace and the displacement reference voltage Era. Become. The output signal from the comparator COM P a is supplied to the actuator ACT of the magnetic head H via the phase compensation circuit PH1, the fixed contact a of the switch S3, the movable contact C, and the buffer amplifier BAI.

As a result, the actuator AC of the magnetic head described above
T is a state in which the error signal output from the comparator C0MPa is zero, that is, crosstalk of the control signal for controlling the recording position on the rotating magnetic recording medium MC read from the adjacent recording trace by the magnetic head H. The magnetic head H is displaced to a position where the voltage value generated based on is equal to the displacement reference voltage set in the displacement reference voltage source Era.

By the way, the output signal of the sensor 8 which generates a signal corresponding to the displacement of the actuator due to the above-mentioned displacement operation of the actuator ACT is converted into a voltage Es by the sensor output signal voltage conversion circuit SEC, and this is converted into the voltage Es by the comparator C0MPb. It is supplied to the inverting input terminal, the differentiating circuit DFC, and the sample hold circuit SH2.

The movable contact C of the switch S2 is connected to the non-inverting input terminal of the comparator C0MPb, and the fixed contact a of the switch S2 is connected to the reference for the displacement angle of the movable part 6 of the actuator ACT. A reference voltage Erb is applied thereto, and the output signal of the sample and hold circuit SH2 is applied to the fixed contact of the switch S2.

The operation of the switch S2 and sample hold circuit SH2 described above is shown in FIG. 5(f) according to the timing of the control signal shown in FIG. 5(d) sent from the control circuit OCT. controlled as follows. Displays a and b in the fifth time (f) indicate the switching mode of the movable contact C of the switch S2. Further, the sample-and-hold circuit SH2 is assumed to be in a hold state in the portion shown as a high level state in (f) of FIG. 5 (note that (s) and (h) of FIG. 5) a in

b is also displayed on switch S3. (This shows the switching mode of the movable contact C of S4.)

Therefore, the movable contact C of the switch S2 is the fixed contact a.
In response to switching to the fixed contact, the comparator C0MPb outputs an error signal based on the output voltage value Es obtained by converting the sensor output signal by the voltage conversion circuit SEC and the reference voltage value Erb. or
Alternatively, an error signal is output based on the output voltage Es' obtained by converting the sensor output signal by the voltage conversion circuit SEC and the output voltage Es' obtained by converting the sensor output signal held by the sample hold circuit SH2 described above by the voltage conversion circuit SEC. It is.

The output signal of the comparator C0MPb described above is sent to the adder circuit ADD.
In I, the above-mentioned sensor output signal is converted to a voltage conversion circuit S.
After the output voltage Es converted by the EC is added to the signal differentiated by the differentiating circuit DFC, the fixed contact b of the switch S3 → the movable contact C → the buffer amplifier BA
It is supplied to the actuator ACT of the magnetic head H via I.

In a state where the movable contact C of the switch S2 described above is switched to its fixed contact a side, the comparator C0MP
The output signal supplied from b to the adder circuit ADDI is an error signal (Erb-Es) between the output voltage value Es obtained by converting the sensor output signal described above by the voltage conversion circuit SEC and the reference voltage value Erb described above. As described above, this error signal is generated by adding the output voltage Es obtained by converting the sensor output signal by the voltage conversion circuit SEC to the signal differentiated by the differentiation circuit DFC and the addition circuit ADDI, and then adding the output voltage Es to the fixed contact of the switch S3. b → the same movable contact C → the buffer amplifier 11BAI, which is supplied to the actuator ACT of the magnetic head H, so that the movable part 6 of the actuator ACT described above → the sensor 8 that generates a signal corresponding to the displacement of the actuator → the sensor Output signal voltage conversion circuit SEC → comparator C0MPb and differentiation circuit DFC →
Addition circuit ADDI → Fixed contact b of switch S3 → Movable contact C → Buffer amplifier BAI → Actuator ACT
Since a closed-loop negative feedback circuit is constructed such as the fixed part 7 → the movable part 6 →, the movable part 6 of the actuator ACT changes the output of the comparator C0MPb in the closed loop by the operation of the negative feedback loop described above. It is held fixed in a position such that the signal is made zero.

In addition, when the movable contact C of the switch S2 is switched to the fixed contact side, the output signal supplied from the comparator C0MPb to the adder circuit ADDI is converted from the sensor output signal by the voltage conversion circuit SEC. and the output voltage value Es.

A difference signal (Es'') between the voltage Es' held by the sample hold circuit SH2, that is, the output voltage obtained by converting the sensor output signal by the voltage conversion circuit SEC, and the voltage Es' held by the sample hold circuit SH2. -Es), and as described above, after the sensor output signal is added to the signal obtained by differentiating the output voltage Es converted by the voltage conversion circuit SEC by the differentiation circuit DFC and the addition circuit ADDI, By being supplied to the actuator ACT of the magnetic head H via the fixed contact b of the switch S3 → the movable contact C → the buffer amplifier BAI, a signal corresponding to the displacement of the movable part 6 of the actuator ACT → actuator is generated. Sensor 8 that generates → Voltage conversion circuit SEC of the sensor output signal → Comparator C0MPb and differentiation circuit DF
C→addition circuit ADDI→fixed contact b of switch S3→movable contact C→buffer amplifier BAI→fixed part 7 of actuator →movable part 6. → Since a closed-loop negative feedback circuit is constructed, the movable part 6 of the actuator ACT is placed at a position where the output signal of the comparator C0MPb in the closed loop is made zero by the operation of the negative feedback loop. , that is, the sampling pulse sent from the control circuit OCT causes the sample hold circuit SH2 to
The actuator is moved to a position where the voltage Es' held at Es' (the voltage that holds the output voltage obtained by converting the sensor output signal by the voltage conversion circuit SEC) is equal to the output voltage Es' obtained by converting the sensor output signal by the voltage conversion circuit SEC. The movable part 6 of the ACT is placed in a fixed state.

Further, the output signal of the comparator C0MPb described above is generated when the movable contact C of the switch S4 is switched to the fixed contact a side, 1-phase compensation circuit PH2 → fixed contact a of the switch S4 → movable contact C → buffer amplifier BA2 It is supplied to the transfer motor Mf via the transfer motor Mf.

Now, when the apparatus shown in FIG. 4 is in a recording standby state, the gate signal (m) for opening and closing the recording signal gate RG sent from the control circuit CCT is
The gate signal (n) for opening and closing the reproduction signal gate PAG is at a low level as shown in (m) of the figure, and the gate signal (n) for opening and closing the reproduction signal gate PAG is high as shown in (n) of FIG. Level status has been made.

As a result, in the recording standby state, the signal read by the magnetic head H is supplied to the reproduction system PBA through the reproduction signal gate PAG. By the way, since the signal read by the magnetic head H includes a control signal for controlling the recording position in the rotating magnetic recording medium MC, the rotating magnetic field included in the output signal from the recycled yarn PBA A control signal for controlling the recording position in the recording medium MC is a low pass filter LPF.
Extracted by I.

A control signal for controlling the recording position on the magnetic recording medium MC extracted by the low-pass filter LPFI is converted into a voltage by the converter PvC and supplied to the "C sample and hold circuit SHI."

Now, if the magnetic head H is near the n-th recording trace on the magnetic recording medium MC, in this case, the magnetic head H
The control signal for controlling the recording position in the magnetic recording medium MC read by the n
A control signal for controlling the recording position in the magnetic recording medium MC read from the n-th recording trace, and a magnetic field recorded in the (n-1)th recording trace adjacent to the n-th recording trace. A control signal for controlling the recording position on the recording medium MC is read out as a crosstalk signal.

As mentioned above, what is actually used as the control signal for controlling the recording position on the magnetic recording medium MC is the control signal for controlling the recording position on the magnetic recording medium MC recorded in the adjacent recording trace. is a signal read out as crosstalk, so when the magnetic head H is near the n-th recording trace as described above, among the two signals successively output by the magnetic head H, (n-1 ) The control signal for controlling the recording position in the magnetic recording medium MC read as crosstalk from the recording trace is the signal actually needed for position control, and in the example of explanation currently being considered, These are times Tl and T3 in Figure 6.
This is a signal read by the magnetic head H at .

So, as in the explanation example I'm thinking of now, the magnetic head H is
Regarding the condition near the th record trace.

A control signal is supplied from the control circuit OCT to the sample and hold circuit SHI to enable the sample and hold circuit SHI to perform sample and hold operations at time positions according to the time series of times Tl, T3, . . . do.

Note that even when the magnetic head H is near the (n-2)th recording trace, when the magnetic head H is near the (n-4)th recording trace, etc., the time series of times TI, T3, etc. The sample and hold circuit S at the time position according to
The HI causes a sample and hold operation, and when the magnetic head H is near the (n-1)th recording trace and when the magnetic head H is near the (n+1)th recording trace, the magnetic head In cases where H is near the (n+3)th record trace, time T2 in FIG.
．． The sample and hold circuit SHI performs a sample and hold operation at a time position that follows the time series of T4, . . . .

In the state where the magnetic head H is tracing near the n-th recording trace as described above, the voltage sampled and held by the sample-and-hold circuit SHI is adjacent to the n-th recording trace that the magnetic head H is tracing. This is based on a crosstalk signal caused by a control signal for controlling the recording position in the magnetic recording medium MC recorded on the (n-1)th recording trace, and when this is given to the ratio fJ 11 COM P a, the comparison In the case of the comparator C○MPa, the voltage and displacement based on the crosstalk signal and the displacement reference voltage source Era are connected to the comparator COM P a
The comparator COM P a generates a crosstalk signal based on a control signal for controlling the recording position in the adjacent (n-1)th recording trace. An error voltage between the base voltage and the displacement reference voltage is output.

Then, the output signal from the comparator C0MPa described above is 1
The signal is supplied to the actuator ACT of the magnetic head H via the phase compensation circuit PHI, the fixed contact a of the switch S3, the movable contact C, and the buffer amplifier BAI.

As a result, the actuator AC of the magnetic head described above
T is the position where the reference displacement amount of the magnetic head H and the actual displacement amount match, that is, the nth recording trace that is separated from the (n - 1)th recording trace by a predetermined correct recording trace interval. The magnetic head H is positioned above.

The position of the magnetic head H is set as described above, and at time ts after the magnetic head H has come to rest on the nth recording trace at time to in FIG. When operated as shown in FIG. 5 (Q), at the time t1 of the rise of the vertical synchronization signal that appears for the first time after the above-mentioned time ts, the changeover control signal supplied from the control circuit CCT to the switch S4 causes the changeover switch S4 to be turned on. The movable contact C is switched from the fixed contact a side to the fixed contact side as shown in (h) in FIG.
The transfer body FA is held at the rotational position at 1 time t1, and transfer is stopped at time t1, and at the time t1, the control circuit OC
From T to sample and hold circuit SHI in FIG.
A trace switching pulse (g) as shown in g) is supplied.

The recording trace switching pulse (g) is the sixth one by time t1.
The sampling operation in the sample-and-hold circuit SHI that was performed in the time series of times Tl, T3, etc. in the figure is now changed to the sampling operation in the time series of times T2, T4, and so on in Figure 6. Switch to

In some examples, the magnetic head H from time tO to time t1
It is said that the position was correctly located on the nth recording trace, and the error signal from the comparator COM P a between the above-mentioned time to and time t1 was in a zero state. As shown in FIG.
2. By switching to the sampling operation at the time according to the time series T4..., an error signal is output from the comparator COM P a after time t1, and the error signal is sent to the phase compensation circuit PHI. →Switch S3
Fixed contact a → Movable contact C → Buffer amplifier BAI →
The fixed part 7 of the actuator ACT is supplied to the fixed part 7 of the actuator ACT through the path from the fixed part 7 of the actuator ACT to the movable part 6, so that the magnetic head H attached to the movable part 6 of the actuator ACT is adjusted to the reference displacement amount of the magnetic head H. and the actual displacement amount, that is, the position is separated from the nth record by a predetermined correct record trace interval (n+IB
Time t continues until the state is located on the third record trace.
1 to time t2 rapidly from the nth record trace (n+
1) Displaced to the th record trace.

As mentioned above, the magnetic head H attached to the movable part 6 of the actuator ACT between time t1 and time t2
is rapidly displaced from the nth trace to the (n+1)th trace.

After time t1, a sensor (position detection sensor or angle detection sensor) 8 that generates a signal corresponding to the displacement of the actuator, which is provided at a position separated from the movable part 6 of the actuator ACT by a minute distance, An output signal is sent out, which is converted into a voltage Es (indicated as Erb+E1 in FIG. 5) by the sensor output signal voltage conversion circuit SEC, and is connected to the inverting input terminal of the comparator C0MPa, the differentiating circuit DFC, and the sample. The signal is supplied to the hold circuit SH2.

As shown in (e), (f), and (h) of FIG. 5, the switches S2 and S3 immediately after the above-mentioned time t1
．． The movable contact C in S4 is switched to the fixed contact a side for switches S2 and S3, and to the fixed contact side for switch S4, so in this state, the above-mentioned sensor The voltage Es (shown as Erb+E1 in FIG. 5) output from the output signal voltage conversion circuit SEC has no effect.

The sampling operation in the sample-and-hold circuit SHI changes from a state following the time series of times Tl, T3, . . . in FIG. 6 to times T2, . . . in FIG. After time t1 when the state is switched to follow the time series of T4..., the control circuit CCT sends out the signal at time ta immediately before time t2 of the rise of the first appearing field discrimination signal ((b) in FIG. 5). A control signal as shown in FIG. 5(d) causes the switches S2. When the movable contact C of S3 is switched from the fixed contact a side to the fixed contact side at time ta, and the sample hold circuit SH2 is put into the hold mode at time ta (shown as Erb+E1 in FIG. 5). is held in the sample-and-hold circuit SH2, and the held voltage Es' (Er in FIG.
b+E1) is supplied to the non-inverting input terminal of the comparator C0MPb through the fixed contact and the movable contact C of the switch S2, so that after time ta, the comparator COM
At 'Pb,' the voltage Es' held in the sample-and-hold circuit SH2 via the switch S2 (shown as Erb + El in FIG. 5) and the voltage conversion circuit for the sensor output signal described above after time ta. An error signal ((a) in FIG. 5) with respect to the voltage Es output from the SEC is output.

Since the movable contact C of the switch S3 is switched to the fixed contact side after the above-mentioned time ta, the comparator C
0MPb → Adder ADDI → Fixed contact b of switch S3
→ Movable contact C → Buffer amplifier BA1 → Fixed part 7 of actuator ACT → Movable part 6 → Sensor (position detection sensor or angle detection sensor) 8 that generates a signal corresponding to the displacement of the actuator → Voltage of sensor output amount Conversion circuit 5EC-+differentiation circuit DFC and comparator C0MPb→
to form a closed-loop negative feedback circuit.

The movable part 6 of the actuator ACT is connected to the comparator C0M in the closed loop by the operation of the negative feedback loop described above.
It is fixed at a position such that the output signal of Pb is made zero.

As described above, the state in which the output signal of the comparator COM P b in the closed loop is set to zero maintains the initial state in which the magnetic head H is correctly displaced from the n-th recording trace to the (n+1)-th recording trace. It is in a state of being Therefore, the recording state of the magnetic head H when the recording/reproducing apparatus is in the frame recording mode corresponds to the state required at the start of frame recording.

Next, the gate signal (m) for opening and closing the recording signal gate RG sent from the control circuit OCT at time t2 changes from a low level state to a high level state at time t2, and the recording signal gate RG changes to a high level state at time t2. The gate signal (n) for opening and closing the reproduction signal gate PAG changes from a high level state to a low level state at time t2, and the reproduction signal gate PAG closes. Further, the gate signal (m) for opening and closing the recording signal gate RG sent from the control circuit CCT changes from a high level state to a low level state at time t3, and the reproduction signal gate PAG changes from a high level state to a low level state at time t3.
The gate signal (n) for opening and closing changes from a low level state to a high level state at time t3, and the reproduction signal gate PAG opens at time t3, from time t2 to t3 shown in FIG. During the period, when the recording operation for one field period ends at time t3, when the recording signal is recorded on the (n+1)th recording trace on the magnetic recording medium MC for one field period, the magnetic head H finishes the recording operation for one field period. Control circuit OCT
As described above, the gate signal (m) for opening and closing the recording signal gate RG sent from the control port w changes from a high level state to a low level state at time t3.
! As the control signal shown in FIG. 5(d) sent from the ccT changes from a high level state to a low level state at time t3, the control signals shown in FIG. 5(e) and (f)
), as shown in (h), the switch S is turned on at time t3.
2. S3. The movable contact C in S4 is switched from the fixed contact side to the fixed contact a side, and by time t4, the transfer motor Mf and actuator ACT return to the initial state at time to described above.

(o) in FIG. 5 is a diagram showing the state in which the magnetic head H moves from the n-th recording trace to the (n+1)-th recording trace, and (p) in FIG. FIG.

(Effects of the Invention) As is clear from the above detailed explanation, the present invention utilizes a tracking reference signal read out from a recording medium by a recording/reproducing element in a reproduction mode to perform recording/reproduction in a closed-loop tracking control system. an actuator capable of driving and displacing the element; a sensor generating a signal corresponding to the displacement of the actuator; a comparator comparing the signal voltage generated by the sensor with a reference signal voltage; A control method for a drive displacement actuator for a recording/reproducing element, in which the output signal of the comparator is subjected to phase compensation and then negatively fed back to the actuator to maintain the posture of the actuator in a recording mode.

An actuator capable of driving and displacing a recording/reproducing element in a closed loop tracking control system using a tracking reference signal read out from a recording medium by a recording/reproducing element in a reproduction mode, and a signal corresponding to the displacement of the actuator. a comparator for comparing the signal voltage generated by said sensor with a reference signal voltage.

During the recording mode, the output signal of the comparator described above is subjected to phase compensation and then negatively fed back to the actuator.

Control of the actuator for drive displacement of the recording/reproducing element, in which the posture of the actuator is maintained in the recording mode, and in the reproduction mode, the output signal of the above-mentioned comparator is returned to the transport motor after phase compensation. Therefore, in the control method of the drive displacement actuator of the recording/reproducing element of the present invention, the recording method used to sequentially record and form recording traces at very fine recording trace intervals on a rotating recording medium during recording The element also serves as a reproducing element that is driven and displaced by an actuator provided in the tracking control system so that the recording element can correctly track the sequential recording traces on the rotating recording medium under tracking control during the reproducing mode. A recording/reproducing device using a recording/reproducing element as a component, in which a center support with small stiffness (high compliance) is used as an actuator to which the recording/reproducing element is attached, or Even if the dynamic range of the tracking control system is widened by using a structure that can be freely rotated by a rotation axis, and tracking control during playback is performed well, the actuator ACT is not activated during recording. Movable part 6 → sensor 8 that generates a signal corresponding to the displacement of the actuator → voltage conversion circuit SEC for sensor output signal → comparator GOMP and differentiation circuit DFC → addition circuit ADDI → fixed contact R of changeover switch SW3 → movable contact V → Actuator drive amplifier ADA → Fixed part 7 of actuator ACT → Movable part 6 of actuator ACT Since the actuator can be kept in a fixed state, the recording state of the magnetic head H can be set as desired when the recording/reproducing device is in the recording mode, and the actuator has low stiffness (high compliance). Those in which the central support is used as a component.

Alternatively, even if an actuator that is rotatable by a rotation axis is used, the actuator ACT is supported with great stiffness by being installed in the stabilized closed-loop negative feedback circuit as described above. According to the control method of the drive displacement actuator of the recording/reproducing element of the present invention, the actuator can function as an actuator equivalent to a one-dimensional drive actuator in a well-damped state. The movable part 6 of the ACT is fixed at a position where the output signal of the comparator COMP in the closed loop becomes zero by the operation of the negative feedback loop described above, and is prevented from being displaced by disturbances. It is possible,
Furthermore, during playback, the actuator can be transported so that the center of its drive displacement range always faces the recorded trace, and the method of the present invention satisfactorily solves the problems of the conventional methods described above. It will be done.

[Brief explanation of the drawing]

1 and 4 are block diagrams of different embodiments of the control system of the drive displacement actuator of the recording/reproducing element of the present invention, FIG. 2(n) and FIG. 2(b), and FIG. The figure is a block diagram for explanation, FIG. 5 is a waveform diagram for explanation, and FIG. 6 is a plan view of a recording trace pattern. MC...Rotating recording medium, H...Magnetic head, ACT
...actuator, P...rotation axis 1Md...drive motor, FA...phase shifter, SEC...voltage conversion circuit for sensor output signal, COMP...comparator, DEF
...Differential circuit, SWI~SW3...Selector switch,
ADDI. ADD2...addition circuit, ADA...actuator drive amplifier, PrA...preamplifier, TSC...tracking control circuit, Pct, PO2, PH1, P)I
2...Phase compensation circuit, FMDC...Motor rotation control circuit for transfer, FDA...Motor drive amplifier for transfer, R
A...recording amplifier, PSD...playback signal processing circuit,
MTV...Monitor receiver, S Hl, S H2...
- Sample hold circuit, 1... Rotation shaft of drive motor Md, 2... Rotation shaft of transfer motor Mf, 3...
Reducer, 4... Feed screw, 5... Guide surface, 6...
- Movable part of actuator ACT, 7... Fixed part of actuator ACT, 8... Sensor (position detection sensor or angle detection sensor) that generates a signal corresponding to the displacement of the actuator.ゐ2 Plan (b)

Claims (1)

[Scope of Claims] 1. An actuator capable of driving and displacing the recording/reproducing element in a closed-loop tracking control system using a tracking reference signal read out from the recording medium by the recording/reproducing element in the reproduction mode; A sensor that generates a signal corresponding to the displacement of the actuator, a comparator that compares the signal voltage generated by the sensor with a reference signal voltage, and a phase compensation that applies phase compensation to the output signal of the comparator in the recording mode. Control method 2 for the drive displacement actuator of the recording/reproducing element, in which negative feedback is sent to the actuator to maintain the posture of the actuator in the recording mode.As the voltage of the reference signal supplied to the comparator, Control method 3 of the actuator for driving displacement of a recording/reproducing element according to claim 1 using a generated predetermined constant voltage, the voltage of the sensor at the start of recording is used as the voltage of the reference signal supplied to the comparator. Control method 4 for a drive displacement actuator for a recording/reproducing element according to claim 1 using an output signal that maintains the voltage, and a tracking reference signal read from a recording medium by the recording/reproducing element in a reproduction mode. an actuator that can drive and displace a recording/reproducing element in a closed-loop tracking control system, a sensor that generates a signal corresponding to the displacement of the actuator, and a signal voltage generated by the sensor and a reference. A comparator for comparing the signal voltage with the signal voltage, and a negative feedback to the actuator after performing phase compensation on the output signal of the comparator during the recording mode to maintain the posture of the actuator during the recording mode. , Control method 5 for the drive displacement actuator of the recording/reproducing element, in which the output signal of the comparator described above is phase-compensated and then fed back to the transport motor in the reproduction mode. Control method 6 of the actuator for driving displacement of a recording/reproducing element according to claim 4 using a predetermined constant voltage generated by a voltage source, as the voltage of the reference signal supplied to the comparator at the start of recording. A control method of an actuator for driving displacement of a recording/reproducing element according to claim 4, using an actuator that maintains the voltage of the output signal of the sensor in claim 4.