JPH0438745A - Capstan motor controller and reel motor controller - Google Patents

Abstract

PURPOSE:To obtain a reproduced picture very easy to see by controlling the speed of a capstan motor and a reel motor to make mean traveling speed N-fold in a search mode at the time of reproduction so that the picture is outputted at a tape speed N-times as high as the tape speed of recording. CONSTITUTION:A speed data output circuit 102 to set the revolving speed of the capstan motor 107, a frequency generator 109 to detect the revolving speed of the motor 107, and a speed control circuit 103 to make the revolving speed of the motor 107 the revolving speed set by the circuit 102 based on the output of the frequency generator are provided. The output circuit 102 outputs speed setting data so that the mean speed becomes the N-fold speed at the time of the N-fold speed reproduction of the magnetic tape. Thus, a reproduced output level is prevented from lowering in a fixed pattern, and such trouble that the picture data of the specified part of the reproduced picture is left as it is not re-written in a reproduced picture output system can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a capstan motor control device and a reel motor control device of a helical scanning type magnetic recording/reproducing device used in a VTR or the like.

Conventional technology magnetic recording and reproducing devices (hereinafter simply referred to as VTR) include:
A search mode (high-speed playback mode) is provided in which the magnetic tape is run at a speed N times the tape running speed during recording (N>1) to search for a program recorded on the magnetic tape. In the search mode in which the capstan motor is rotated at high speed, the rotation speed of the capstan motor is controlled to be N times the rotation speed in the recording mode.

FIG. 15 shows the relationship between recording tracks and head scanning trajectories during 5x speed reproduction. In FIG. 15, 1501 is a magnetic tape, which is transported in the direction of arrow 1502. On the magnetic tape 15011, recording tracks AI, A2 . ...,
A8. ...and B1°B2. ..., B8.
... is formed. An arrow 1503 indicates the scanning direction of the magnetic head during recording. Magnetic head (PAL) 150
7 is recording track AI.

A2. It is a magnetic head that has the same azimuth angle as the head that recorded ..., and is a magnetic head (FBI) 150.
8 is recording track BLB2. This is a magnetic head that has the same azimuth angle as the head that recorded... 150
4.1506 is magnetic head (PAL) 1 for 5x speed playback
A scanning locus 507 is shown, and a scanning locus 1505 is similarly a scanning locus of a magnetic head (FBI) 1508 during 5x speed reproduction.

FIG. 1θ shows changes in the playback output level during 5x speed playback. FIG. 16(a) shows the rotational position of the magnetic head H-
With the 8W signal, when the H-3W signal is High, the magnetic head (PAL) 1507 scans the magnetic tape 1501, and conversely, when the H-8W signal is Low, the magnetic head (PAL) 1507 scans the magnetic tape 1501.
I) 1508 scans the magnetic tape 15011 and reproduces the signal recorded on the magnetic tape 2. The reproduced signal output waveform obtained at this time is as shown in FIG. 16(b), and the magnetic head (PA1) 1507 moves to the recording track B1. B2. . . , and the magnetic head (FBI) 1508 scans the recording track A1 . A2
．． . . . The reproduction signal output level decreases at the timing of scanning.

In the conventional configuration described in item 1 of "Problems to be Solved by the Invention," black horizontal stripes called noise bars appear on the playback screen at locations corresponding to portions where the playback signal level has decreased. For this reason, in search mode, the tape running speed is set to an odd number multiple of the tape speed during recording, and this noise bar is fixed on the playback screen in order to make the playback screen in search mode as easy to see as possible. . However, on the other hand, in systems that process playback images using image memory, image data in specific parts of the playback screen may remain unwritten, resulting in the problem that the playback screen in search mode is difficult to see. Was.

Furthermore, in JOG mode or a mode in which the running speed of the magnetic tape is controlled by torque control of the take-up reel motor, tracking control is not performed to ensure that the magnetic head correctly scans the recording track, and the running speed of the magnetic tape is If the speed is almost the same as the tape running speed during recording, there is a possibility that the playback output of the magnetic head will always remain low during playback operation, resulting in the problem that a normal playback image cannot be obtained. be.

The present invention solves the above-mentioned conventional problems, and prevents the playback output level from decreasing due to a fixed pattern in a search mode in which magnetic tape is played back at N times the speed of recording. It is an object of the present invention to provide a capstan motor control device or a reel motor control device for a magnetic recording/reproducing device in which image data at a specific portion of a playback screen does not remain unwritten in a playback image output system.

Furthermore, in a mode in which the magnetic tape is run at approximately the same speed as during recording, the output of the magnetic head remains low even if tracking control is not performed, in which the magnetic head scans the regular recording track on-track. It is an object of the present invention to provide a capstan motor control device or a reel motor control device for a magnetic recording and reproducing device that does not perform a reproducing operation.

Means for Solving the Problems To achieve this object, the magnetic recording and reproducing apparatus of the present invention includes a rotation speed setting means for setting the rotation speed of the capstan motor, and a rotation speed for detecting the rotation speed of the capstan motor. a detection means, and a speed at which a capstan motor control signal is output based on the output of the rotation speed detection means so that the rotation speed of the capstan motor becomes a rotation speed set by the output data of the rotation speed setting means. and a control circuit, and the rotational speed setting means changes the set speed to data at N times speed or less and data at N times speed or more during N times speed playback in which the running speed of the magnetic tape is played back at N times the speed at which it was recorded. When combined, speed setting data is output so that the average speed becomes N times faster.

Effect The present invention has the above-described structure, so that when recording a magnetic tape, the N
In search mode, which plays back at twice the speed, a fixed pattern prevents the playback output level from decreasing, and in a playback image output system using image memory, image data in a specific part of the playback screen remains unwritten. It is possible to provide a capstan motor control device for a magnetic recording/reproducing device that does not cause such problems.

Example Embodiments of the present invention will be described based on the drawings.

FIG. 1 is a schematic diagram of a capstan motor control device of a magnetic recording/reproducing apparatus according to a first embodiment of the present invention.

In FIG. 1, 101 is a system control circuit which outputs mode signals corresponding to each mode of the magnetic recording/reproducing apparatus. A speed data output circuit 102 outputs rotational speed setting data for the capstan motor in the N-times search mode based on the N-times search mode signal output from the system control circuit 101. 103 is a capstan motor speed control circuit;
Based on the rotation speed detection signal output from the frequency generator (FG) 109 attached to the capstan motor 107, the rotation speed of the capstan motor is set by the rotation speed setting data output from the speed data output circuit 102. Outputs a speed error signal to achieve the specified speed. Further, 104 is a phase control circuit for the capstan motor,
In the reproduction mode, a phase error signal is output so that the phase reference signal and the reproduction control signal have a predetermined phase relationship. The speed error signal and the phase error signal are mixed by a mix circuit (MIX) 105 and then input to a motor drive circuit 106. The motor drive circuit 106 rotates the capstan motor 107 by passing a drive current corresponding to the input signal to the capstan motor 107. The magnetic tape 108 runs at a transport speed corresponding to the rotational speed of the capstan motor 107. Magnetic head 114,1
15 rotates and scans the magnetic tape 108 and reproduces the signal recorded on the recording track. The signal regenerated by the magnetic herad 114 is amplified by a regenerative amplifier (AMP) 111,
The signal is input to the switch circuit 112. The signal regenerated by the magnetic herad 115 is amplified by a regenerative amplifier (AMP) 110 and input to a switch circuit 112. switch circuit 1
At step 12, the input signal is switched based on the H-8W signal representing the rotational position of the magnetic heads 114, 115, and the reproduced signal is input to the reproduced signal processing circuit 113. The reproduction signal processing circuit 113 processes the input reproduction signal and outputs a reproduction video signal from a terminal 116.

The operation of the first embodiment of the present invention will be explained based on FIGS. 2 and 3. FIG. 2 is a plan view showing the positional relationship between the magnetic tape and the head scanning locus in a search mode in which the running speed of the magnetic tape is five times the speed at which signals are recorded, and FIG. 3 is a plan view showing each part of the circuit shown in FIG. FIG.

Figure 3(a) shows the H-8W signal, and the H-8W signal is
When the H-8W signal is LOW, the magnetic head 114 scans the magnetic tape 108, and conversely, when the H-8W signal is LOW, the magnetic head 115 scans the magnetic tape 108. Same figure (b)
is a waveform indicating the value of the rotational speed setting data output from the speed data output circuit 102, in which the setting speed changes in a sinusoidal manner around ×5 (5x speed), and during one revolution of the rotary head. The average set speed is ×5.

When the rotational speed of the capstan motor 107 is set in this way, the positional relationship between the head scanning locus and the magnetic tape is as shown in FIG. In FIG. 2, a scanning trajectory 206 indicated by a broken line indicates a scanning trajectory of the magnetic heads 114 and 115 when the rotational speed of the capstan motor 107 is constant x5. When the tape running speed changes sinusoidally around the 5x speed as shown in FIG. 3(b), the tape running speed changes sinusoidally around the 5x speed in response to the rotational speed of the capstan motor. Therefore, the scanning trajectory of the magnetic head 114 becomes as shown by curves 203 and 205, and the scanning trajectory of the magnetic head 115 becomes as shown by a curve 204. FIG. 3(C) shows the reproduction signal output level of each magnetic head obtained at this time. As shown in the same figure (C),
Because the positional relationship between the scanning locus of the magnetic head and the recording track is different between the head scanning sections ■ and ■, the head scanning sections ■ and ■ are different.
The reproduced signal output level waveforms are different in these cases, and when the reproduced signal output level waveforms of the head scanning sections ■ and ■ are superimposed as shown in FIG. 3(d), it can be seen that a reproduced signal output of a certain level or higher can be obtained. . In other words, when one field of image is recorded on each track, according to this embodiment, information at a specific position of the image is reproduced without being lost during one rotation of the rotating drum equipped with a magnetic head. This makes it possible to solve the conventional problem that specific pixels cannot always be rewritten in a system that performs reproduction signal processing using an image memory.

As described above, according to the capstan motor control device of the magnetic recording/reproducing apparatus of this embodiment, it is possible to solve the problem that information at a specific location on a recording track cannot always be reproduced in the search mode. Therefore, in a magnetic recording and reproducing device that uses an image memory to process reproduced video signals, the problem of pixels remaining at specific locations without being rewritten can be solved, and a reproduced video that is extremely easy to view can be obtained. The practical effects are great.

Next, the speed data output circuit 10 of the first embodiment of the present invention
A specific circuit for realizing 2 will be explained with reference to FIGS. 4 and 5.

FIG. 4 is a schematic configuration diagram showing an example of the speed data output circuit 102 in FIG. 1.

FIG. 5 is a waveform diagram showing waveforms of various parts of the speed data output circuit shown in FIG. 4.

In FIG. 4, a drum FG signal 5a, which is a signal for detecting the rotational speed of a rotating drum device equipped with a rotating magnetic head, is inputted from a terminal 401.

The waveform of the drum FG signal 5a is shown in FIG. 5(a).

A terminal 405 outputs H-, which indicates the rotational position of the rotating magnetic head.
An 8W signal 5b is input. The reset signal 5 is generated using the mono multi circuit (MM) 403 based on the H-8W signal 5b.
Create c. The H-8W signal 5b is shown in FIG. 5(b), and the reset signal 5C is shown in FIG. 5(c). 402 is a counter circuit, to which the drum FG signal 5a is input as a clock input, and the reset signal 5c is input as a reset signal.
is input. The count value data 5d of the counter 402 is as shown in FIG. 5(d), and the count value data 5d represents the rotational position of the magnetic head. This count value data 5d becomes address data in a storage circuit 404 in a read-only memory (ROM), and from the storage circuit 404, capstan motor speed setting data 5 corresponding to the rotational position of the magnetic head is output.
e is output. The capstan motor speed setting data 5e shown in FIG. 5(0) is data that changes sinusoidally around the 5x speed when the tape speed is 5x, for example, and is data to be written into the storage circuit 404. It goes without saying that by rewriting , it is possible to realize any speed setting data waveform.

As explained above, according to this embodiment, a speed data output circuit can be realized with a simple 11i- configuration. In addition, in this embodiment, the capstan motor speed setting data stored in the storage circuit is waveform data such that the tape running speed changes in a sine wave pattern, but the reason for changing the tape running speed in a sine wave pattern is This is to ensure that the speed changes smoothly in consideration of the responsiveness due to the moment of inertia of the capstan motor, and to reduce fluctuations in the tension of the magnetic tape.

Next, a second embodiment of the present invention will be described using FIGS. 6, 7, and 8.

FIG. 6 is a schematic configuration diagram of a reel motor control device of a magnetic recording/reproducing apparatus according to a second embodiment of the present invention.

In the capstan motor control circuit shown in Figure 1, 1/
It is difficult to achieve slow playback at 30x speed and search mode at 6x speed or higher because the control range is too wide and exceeds the limits of capstan motor control. Therefore, in the search mode of 6x speed or higher, the capstan motor is not used, but the search mode is realized by controlling the rotation of the take-up reel motor to control the tape running speed.

Referring to FIG. 6, a reel motor control device for a magnetic recording/reproducing apparatus, which is a second embodiment of the present invention, will be described using a seven-times-speed search mode as an example.

In FIG. 8, a magnetic tape 609 supplied from a supply reel 607 passes through a post 614 to a rotating drum 608.
After passing through the post 615 , it travels in the direction of arrow 610 and is wound onto a winding wheel 606 . Magnetic heads 114 and 115 are mounted on the rotating drum 608. A system control circuit 601 outputs mode signals corresponding to each mode of the magnetic recording/reproducing apparatus.

A speed data output circuit 602 outputs tape running speed setting data for setting the actual magnetic tape running speed based on the N times speed data output from the system control circuit 601.

620 is a tape running speed detection circuit;
Rotation speed detection signal output from frequency generator (FG) 612 attached to 06 and supply reel 607
The running speed of the magnetic tape 609 is detected based on a rotational speed detection signal output from a frequency generator (FG) 611 attached to the magnetic tape 609 .

A speed control circuit 803 determines the running speed of the magnetic tape 609 based on the tape running speed signal output from the tape running speed detection circuit 620.
A speed error signal is output so that the speed is set by the tape speed setting data output from the tape speed setting data. The speed error signal output from the speed control circuit 603 is input to the take-up reel motor drive circuit 604. The take-up reel motor drive circuit 604 rotates the take-up reel motor 605 by passing a drive current corresponding to the input signal to the take-up reel motor 605, and the magnetic tape 609 is wound onto the take-up reel 606. Therefore, the magnetic tape 609 runs at the transfer speed set by the output data of the speed data output circuit 602.

On the other hand, a tension sensor 613 is provided between the supply reel 607 and the post 614, and the tension sensor 613 outputs a voltage corresponding to the strength of the tape tension between the supply reel 607 and the post 614. The voltage output from the tension sensor 613 is input to the tension control circuit 617.
A tension error signal having a voltage proportional to the difference between the voltage output from the tension sensor 613 and the tension reference voltage input from the terminal 616 is output. The tension error signal is sent to the supply reel motor drive circuit 6.
18, and the supply reel motor drive circuit 618 causes a current corresponding to the tension error voltage to flow through the supply reel motor 619, thereby generating a predetermined rotational torque on the supply reel 607. Therefore, the supply reel 607 and the boss 6
Tension control is performed to set the tension between 14 to a predetermined value.

A second embodiment of the present invention will be described based on FIGS. 7 and 8. FIG. 7 is a plan view showing the positional relationship between the magnetic tape and the head scanning locus in the search mode when the running speed of the magnetic tape is set to 7 times the signal recording speed;
This figure is a waveform diagram for explaining the operation of the reel motor control circuit shown in FIG. 6. FIG. 8(a) shows the H-8W signal, and when the H-8W signal is High, the magnetic head 11
4 scans the magnetic tape 609, and conversely, when the H-8W signal is Low, the magnetic helad 115 scans the magnetic tape 609. FIG. 6(b) is a waveform showing the value of the tape running speed setting data output from the speed data output circuit 602, in which the setting speed changes in a sine wave shape centered on ×7 (seven times speed), and The average set speed during one rotation of the rotary head is x7. In this way, magnetic tape 6
The positional relationship between the head scanning locus and the magnetic tape when the running speed of 09 is set is as shown in FIG.

In FIG. 7, a scanning locus 705 indicated by a broken line indicates the scanning locus of the magnetic heads 114, 115 when the running speed of the magnetic tape 609 is constant x7; As shown in FIG. 8(b), the scanning locus of the magnetic head 114 when the speed is changed sinusoidally around the 7x speed becomes as shown by curves 702 and 704, and the scanning locus of the magnetic head 115 is the curve 703
It will be shown as follows. FIG. 8(C) shows the reproduction signal level obtained in each magnetic head at this time. As shown in FIG. 8(C), since the positional relationship between the scanning locus of the magnetic head and the recording track is different between the head scanning sections ■ and ■, the reproduced signal output level waveform is different between the head scanning sections and ■. As shown in (d), when the reproduction signal output level waveforms of the head scanning sections (2) and (2) are superimposed, it can be seen that a reproduction signal output of a certain level or higher can be obtained. That is,
When one field of image is recorded on each track, according to this embodiment, information at a specific position of the image can be reproduced without missing during one rotation of the rotating drum equipped with a magnetic head. In a system that performs reproduction signal processing using an image memory, it is possible to solve the conventional problem that specific pixels are not always rewritten.

As described above, according to the reel motor control device of the magnetic recording/reproducing apparatus of this embodiment, it is possible to solve the problem that information at a specific location on a recording track cannot always be reproduced in the search mode. Therefore, in a magnetic recording and reproducing device that uses an image memory to process reproduced video signals, the problem of pixels in specific locations remaining without being rewritten can be solved, and a reproduced video that is extremely easy to view can be obtained. The practical effects are great.

Next, a third embodiment of the present invention will be described based on FIGS. 9 to 11.

FIG. 9 is a schematic configuration diagram of a capstan motor control device of a magnetic recording/reproducing apparatus according to a third embodiment of the present invention.

In FIG. 9, 901 is a system control circuit that outputs mode signals corresponding to each mode of the magnetic recording/reproducing apparatus. A speed data output circuit 902 outputs rotation speed setting data for setting the actual rotation speed of the capstan motor based on the 1x speed data output from the system control circuit 901. 903 is a capstan motor speed control circuit, and a frequency generator (FG) 9 attached to the capstan motor 905
Based on the rotation speed detection signal outputted from the speed data output circuit 902, a speed error signal is outputted so that the rotation speed of the capstan motor becomes the speed set by the rotation speed setting data outputted from the speed data output circuit 902. Speed control circuit 90
The speed error signal output from 3 is sent to the motor drive circuit 90.
4 is input. The motor drive circuit 904 rotates the capstan motor 905 by passing a drive current corresponding to the input signal to the capstan motor 905 . The magnetic tape 906 runs at a transport speed corresponding to the rotational speed of the capstan motor 905.

This embodiment targets a mode in which the magnetic tape is transferred by rotating the capstan motor, such as in the JOG mode, but only speed control is applied to the capstan motor control, and no phase control is performed. Therefore, the capstan motor phase control circuit 104 constituting the capstan motor control device of the magnetic recording/reproducing apparatus according to the first embodiment of the present invention shown in FIG. 1 is omitted. The magnetic heads 907 and 908 are connected to the magnetic tape 9
06 and reproduces the signal recorded on the recording track. The signal reproduced by the magnetic head 907 is amplified by a regenerative amplifier (AMP) 909, and the signal is amplified by a regenerative amplifier (AMP) 909.
is input. The signal reproduced by the magnetic head 908 is amplified by a regenerative amplifier (AMP) 910 and then sent to the switch circuit 9.
11. The switch circuit 911 switches the input signal based on the H-3W signal representing the rotational position of the magnetic heads 907 and 908, and inputs the reproduced signal to the reproduced signal processing circuit 912. The reproduced signal processing circuit 912 processes the input reproduced signal and outputs it from a terminal 913 as a reproduced video signal.

A third embodiment of the present invention will be described based on FIGS. 10 and 11. FIG. 10 is a plan view showing the positional relationship between the magnetic tape and the head scanning locus when the capstan motor is controlled so that the running speed of the magnetic tape is approximately the same as that during signal recording. 10 is a waveform diagram showing waveforms of various parts of the circuit shown in FIG. 9. FIG. FIG. 10(a) shows the H-8W signal; when the H-8W signal is High, the magnetic head 907 scans the magnetic tape 906, and conversely, when the H-8W signal is Low, the magnetic head 908 scans the magnetic tape 906. A magnetic tape 908 is scanned. FIG. 9(b) is a waveform showing the value of the rotational speed setting data output from the speed data output circuit 902, in which the setting speed changes sinusoidally around ×1 (1x speed), and the rotating head The average set speed during two rotations is x1. When the rotational speed of the capstan motor is set in this way, the positional relationship between the head scanning locus and the magnetic tape is as shown in FIG.

In FIG. 10, a scanning trajectory 1005 indicated by a broken line is
It represents the scanning locus of the magnetic head 907 when the rotational speed of the conventional capstan motor is constant x1, and the scanning locus 1006 indicated by a broken line similarly represents the scanning locus of the magnetic head 908.

In the operation mode of the magnetic recording/reproducing apparatus described in this embodiment, only speed control is applied to the capstan motor 905, and no phase control is applied to the capstan motor 905.

That is, tracking control for causing the magnetic heads 907 and 908 to scan regular recording tracks is not performed. Therefore, the magnetic head 907 records tracks A1. A
2. A3. . . , the scanning trajectory 1005 is shifted by one track, and similarly, the magnetic head 908 scans the recording tracks B1, B2 .
B3. Where you have to scan...
Since the scanning locus 1006 is shifted by one track, and both the magnetic heads 907 and 908 read back and scan the recording tracks of opposite azimuth, the playback output output from the magnetic heads 907 and 908 is always small during one track scanning. Therefore, the original reproduced image cannot be obtained.

However, in this embodiment, the rotational speed of the capstan motor is changed sinusoidally around x1 as shown in FIG. 11(b), so the tape running speed does not correspond to the rotational speed of the capstan motor. It changes sinusoidally with x1 as the center. Therefore, the scanning locus of the magnetic head 907 is curve 10.
01.1003, and the magnetic head 9
The scanning locus of 08 is shown by curves 1003 and 1004. FIG. 11(C) shows the reproduction signal level obtained in each magnetic head at this time. As shown in FIG. 5C, since the positional relationship between the scanning locus of the magnetic head and the recording track is different in the head scanning sections ■, ■, ■, and ■, the head scanning sections ■, ■, ■, and ■ are different.

The reproduction signal output level waveforms of ■ and ■ are different. Therefore, as shown in FIG. 11(d), the head scanning section ■,
When the reproduced signal output level waveforms of (1), (2), and (2) are superimposed, it can be seen that a reproduced signal output of a certain level or higher can be obtained. In other words, when one field of image is recorded on each track, according to this embodiment, information at a specific position of the image can be reproduced without being lost during two rotations of the rotating drum equipped with a magnetic head. This makes it possible to solve the conventional problem that specific pixels cannot always be rewritten in a system that performs reproduction signal processing using an image memory.

As explained above, according to the capstan motor control device of the magnetic recording and reproducing apparatus of this embodiment, the reproduction mode is such that the running speed of the magnetic tape is almost the same as the tape running speed during recording by controlling the speed of the capstan motor. and
In addition, in a mode where tracking control is not applied, depending on the positional relationship between the magnetic head and the recording track, the reproduction output of the magnetic head is always small during one track scanning period, and a normal reproduced image cannot be obtained. In magnetic recording and reproducing devices that use image memory to process reproduced video signals, pixels at all locations on the screen are rewritten during multiple rotations of a rotating head equipped with a magnetic head, making it extremely easy to see. This has the effect of allowing playback video to be obtained, and its practical effects are great.

Next, a fourth embodiment of the present invention will be described using FIGS. 12, 13, and 14.

FIG. 12 is a schematic configuration diagram of a reel motor control device for a magnetic recording and reproducing apparatus according to a fourth embodiment of the present invention.

In FIG. 12, a mode in which the reel motor is controlled so that the tape speed during playback is almost the same as the tape speed during recording is taken as an example, and the reel motor of the magnetic recording and reproducing apparatus according to the fourth embodiment of the present invention is shown. The control device will be explained.

In FIG. 12, a magnetic tape 1209 supplied from a supply reel 1207 is wound around a rotating drum 1208 via a boss 1214, and after passing through the boss 1209, it travels in the direction of an arrow 1210 and is wound onto a take-up reel 1206. . A magnetic head 1220.1 is mounted on the rotating drum 1208.
221 is installed. A system control circuit 1201 controls the torque of the take-up reel motor 1205 during playback to control the magnetic tape 12.
A mode signal is output that causes the 09 to run at approximately the same speed as when recording. A speed data output circuit 1202 outputs tape running speed setting data for setting the running speed of the magnetic tape 1209 based on a mode signal output from the system control circuit 1201. 122
2 is a tape running speed detection circuit;
The rotation speed detection signal output from the frequency generator (FG) 1212 attached to 6 and the supply IJ-rule 120
Based on the rotation speed detection signal output from the frequency generator (FG) 1211 attached to the magnetic tape 1
The tape running speed is detected and a tape running speed signal is output. The speed control circuit 1203 determines the running speed of the magnetic tape 1209 based on the tape running speed signal output from the tape running speed detection circuit 1222.
A speed error signal is outputted so that the speed set by the tape speed setting data outputted from 202 is achieved.

The speed error signal output from the speed control circuit 1203 is input to the take-up reel motor drive circuit 1204. The take-up reel motor drive circuit 1204 rotates the take-up reel motor 1205 by passing a drive current corresponding to the speed error signal to the take-up reel motor 1205, and the magnetic tape 1209 is wound onto the take-up reel 1206. The magnetic tape 1209 runs at a transfer speed set by the output data of the speed data output circuit 1202.

On the other hand, a tension sensor 1213 is provided between the supply reel 1207 and the post 1214.
A voltage corresponding to the strength of the tape tension between 14 and 14 is output. The voltage output from the tension sensor 1213 is input to the tension control circuit 1217, and the voltage from the tension control circuit 1217 is proportional to the difference between the voltage output from the tension sensor 1213 and the tension reference voltage input from the terminal 1216. A tension error signal is output. The tension error signal is input to the supply reel motor drive circuit 1218, and the supply reel motor drive circuit 1218 supplies a current corresponding to the tension error voltage to the reel motor 1219, thereby generating a rotational torque on the supply reel 1207 to generate a predetermined rotational torque. Pack tension is applied. Therefore, tension control is performed so that the tension between the supply reel 1207 and the boss 1214 becomes a predetermined value.

By the way, as explained in the third embodiment of the present invention, when the tape speed during playback is almost the same as the tape speed during recording, the magnetic head scans the regular recording track while on-track. If tracking control is not performed, depending on the positional relationship between the magnetic head and the recording track, the magnetic head may scan the recording track recorded by the magnetic head with the opposite azimuth, and the reproduction output of the magnetic head at that time There is a problem in that the image is so small that a normal reproduced image cannot be obtained. This embodiment solves this problem.

Next, the operation of the fourth embodiment of the present invention will be explained based on FIGS. 13 and 14.

FIG. 13 is a plan view showing the positional relationship between the magnetic tape and the head scanning locus when the reel motor is controlled so that the running speed of the magnetic tape during playback is approximately the same speed as during signal recording; FIG. 14 is a waveform diagram showing waveforms at various parts of the circuit shown in FIG. 12. FIG. 14(a) shows the H-8W signal; when the H-8W signal is High, the magnetic head 1220 scans the magnetic tape 1209;
When the W signal is Low, the magnetic head 1221 scans the magnetic tape 1209. (b) in the same figure is a waveform showing the value of the tape speed setting data output from the speed data output circuit 1202, in which the setting speed changes in a sine wave shape centered on ×1 (1x speed), and the rotation The average set speed during four rotations of the head is x1. When the running speed of the magnetic tape 1209 is set in this way, the positional relationship between the head scanning locus and the magnetic tape is as shown in FIG. In FIG. 13, a scanning trajectory 130 indicated by a broken line
1 is the scanning locus of the magnetic head 1220 when the running rotational speed of the magnetic tape 1209 is constant x1, and the scanning locus 1302 indicated by a broken line is also the scanning locus of the magnetic head 1209.
221 scanning locus.

At this time, the magnetic tape 1209 is being transported under speed control by a motor, and no tracking control is applied so that the magnetic head scans on-track on a regular recording track. Therefore, the dashed line 130 in FIG.
As shown at 1.1302, the magnetic head 1220. 1
Heads 1220 . 1221
The playback output output from the track is always small during one track scanning period. Therefore, there is a problem that the original reproduced image may not be obtained.

However, in this embodiment, the take-up reel motor is controlled so that the running speed of the magnetic tape changes sinusoidally around the 1x speed as shown in FIG. 14(b).
The scanning trajectory of the magnetic head 1220 is curved 1303, 130.
5,1307. 1309, and the scanning trajectory of the magnetic head 1221 is as shown by curve 1304. 13]
3,1308.1310. Figure 14 (
c) is the reproduction signal level obtained at this time in each magnetic head. As shown in the same figure (C), since the positional relationship between the scanning locus of the magnetic head and the recording track is different in the head scanning sections ■, ■, ■, ■, ■, ■, ■, ■, respectively, the head scanning sections ■~ The reproduced signal output level waveforms during the one-track scanning period of (3) are different, as shown in Fig. 14(d).
As shown in FIG. 3, when the reproduced signal output level waveforms of the head scanning sections (1) to (2) are superimposed, it can be seen that a reproduced signal output of a certain level or higher can be obtained. In other words, when one field of image is recorded on each track, according to this embodiment, information at a specific position of the image can be reproduced without being lost while the rotating drum equipped with the magnetic head rotates four times. This makes it possible to solve the conventional problem that specific pixels cannot always be rewritten in a system that performs reproduction signal processing using an image memory.

As explained above, according to the reel motor control device of the magnetic recording/reproducing apparatus of this embodiment, by controlling the torque of the take-up reel motor, the running speed of the magnetic tape can be made to be approximately the same as the tape running speed during recording. This solves the problem that, depending on the positional relationship between the magnetic head and the recording track, the reproduction output of the magnetic head is always small during one track scanning period, making it impossible to obtain a normal reproduced image. In a magnetic recording and reproducing device that processes reproduced video signals using a magnetic head, pixels at all locations on the screen are rewritten during multiple rotations of a rotating head equipped with a magnetic head, resulting in extremely easy-to-see reproduced video. It's effective.

Further, the present invention is particularly effective in a magnetic recording/reproducing device that converts a video signal into digital data and records the data.

As described in detail, according to the capstan motor control device or reel motor control device of the magnetic recording and reproducing apparatus of the present invention, the magnetic tape is played back at a speed N times the tape speed at the time of recording (N>1). In the search mode that outputs the reproduced image while running the tape, the capstan motor or reel motor speed is controlled so that the average running speed is N times by combining the tape running speed of N times or less and the speed of N times or more. By doing this, the output level of the part corresponding to a specific position of the recording track of the playback signal output in search mode is always low, and therefore, in a system that performs signal processing using image memory, information about a specific pixel is not available. The problem of not being rewritten can be solved, and a reproduced image that is very easy to view can be obtained.

Further, according to the capstan motor control device or the reel motor control device of the magnetic recording and reproducing apparatus of this embodiment, the running speed of the magnetic tape during playback is controlled to be approximately the same as the tape running speed during recording, and In a mode in which tracking control is not performed so that the magnetic head scans on-track on a regular recording track, the reproduction output of the magnetic head may always be small during one track scanning period depending on the positional relationship between the magnetic head and the recording track. In magnetic recording and reproducing devices that process reproduced video signals using image memory, it is possible to solve the problem of not being able to obtain regular reproduced images. Pixels at all locations on the screen are rewritten, resulting in an extremely easy-to-see playback video.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a capstan motor control device of a magnetic recording and reproducing apparatus according to a first embodiment of the present invention, and FIG. 2 is a plan view showing the positional relationship between the magnetic tape and the head scanning locus during 5x speed reproduction. , FIG. 3 is a waveform diagram for explaining the operation of the first embodiment of the present invention, FIG. 4 is a circuit diagram showing a specific example of the speed data output circuit of FIG. 1, and FIG. 5 is a speed data output circuit. A waveform diagram for explaining the operation of the circuit, FIG. 6 is the second waveform diagram of the present invention.
FIG. 7 is a plan view showing the positional relationship between the magnetic tape and the head scanning locus during 7x speed playback, and FIG. FIG. 9 is a schematic diagram of the capstan motor control device of the magnetic recording/reproducing apparatus according to the third embodiment of the present invention, and FIG. 10 is a waveform diagram for explaining the operation of the third embodiment of the present invention. FIG. 11 is a plan view showing the positional relationship between the magnetic tape and the head scanning locus, FIG. 11 is a waveform diagram for explaining the operation of the third embodiment of the present invention, and FIG. 12 is a magnetic diagram of the fourth embodiment of the present invention. A schematic configuration diagram of a reel motor control device of a recording and reproducing apparatus, FIG. 13 is a plan view showing the positional relationship between the magnetic tape and the head scanning locus during 1x speed reproduction, and FIG. 14 shows the operation of the fourth embodiment of the present invention. FIG. 15 is a plan view showing the positional relationship between the magnetic tape and the head scanning locus during 5x speed reproduction, and FIG. 16 is a waveform diagram for explaining the conventional problems. 102.602,902. 1202...speed data output circuit, 103,603,903. 1203・
...Speed control circuit, 104...Phase control circuit, 6
04, 1204... Reel motor drive circuit, 6
02, 1222...Tape running speed detection circuit. Name of agent: Patent attorney Shigetaka Awano and 1 other person 40 years old - Sister 0 years old

Claims (5)

[Claims] (1) a rotational speed setting means for setting the rotational speed of the capstan motor; a rotational speed detection means for detecting the rotational speed of the capstan motor; and a rotational speed detection means for detecting the rotational speed of the capstan motor; and a speed control circuit that outputs a capstan motor control signal so that the rotation speed becomes the rotation speed set by the output data of the rotation speed setting means, and the rotation speed setting means controls the running speed of the magnetic tape. A capstan that outputs speed setting data so that the average speed becomes N times the speed by combining data with the setting speed below N times and data with the setting speed above N times when playing back at N times the speed of recording. Motor control device. (2) The rotational speed setting means includes a rotational head position detection means for detecting the rotational position of the rotational head device, and rotational speed data of the capstan motor corresponding to the rotational head position data output from the rotational head position detection means. 2. The capstan motor control device according to claim 1, further comprising rotational speed data output means for outputting rotational speed data. (3) A reel motor control device for a magnetic recording and reproducing apparatus that controls the running speed of a magnetic tape by controlling the drive torque of a take-up reel motor, the tape running speed setting means for setting the running speed of the magnetic tape. and a tape running speed detection means for detecting the running speed of the magnetic tape, and a running speed of the magnetic tape is set based on the output of the tape running speed detection means using output data of the tape running speed setting means. and a take-up reel motor control circuit for controlling the drive torque of the take-up reel motor so that the magnetic tape travels at a speed N times the speed at which the magnetic tape is recorded. When playing back at N times the speed, the average speed of the magnetic tape is set to N times by outputting a combination of setting data that causes the running speed of the magnetic tape to be N times the speed or less and setting data that makes the running speed of the magnetic tape N times the speed or more. Reel motor control device that outputs setting data. (4) rotational speed setting means for setting the rotational speed of the capstan motor; rotational speed detection means for detecting the rotational speed of the capstan motor; and rotational speed detection means for detecting the rotational speed of the capstan motor; and a speed control circuit that outputs a capstan motor control signal so that the rotation speed becomes the rotation speed set by the output data of the rotation speed setting means, and the capstan motor rotation speed setting means is configured to control the rotation speed of the magnetic tape. When replaying the running speed of at almost the same speed (V_0) as at the time of recording, the set speed is set to data below V_0 and V_0.
By combining the above data, the average speed is V_
A capstan motor control device that outputs speed setting data so that the speed becomes 0. (5) A reel motor control device for a magnetic recording and reproducing device that controls the running speed of a magnetic tape by controlling the drive torque of a take-up reel motor, the tape running speed setting means for setting the running speed of the magnetic tape. and a tape running speed detecting means for detecting the running speed of the magnetic tape, and a running speed of the magnetic tape is set based on the output of the tape running speed detecting means with output data of the tape running speed setting means. and a take-up reel motor control circuit for controlling the driving torque of the take-up reel motor so that the magnetic tape travels at a speed approximately equal to that at the time of recording (V_0). ), the reel motor control device outputs speed setting data such that the average speed becomes V_0 by combining data of the setting speed below V_0 and data above V_0.