JPH01298501A - Tape device - Google Patents

Abstract

PURPOSE:To set up the rotational loci of rotary heads on a magnetic tape to optional shapes even when a reading angle is different by controlling the rotational angular velocity of the rotary heads so that the rotational angular velocity in the recording/reproducing period of the magnetic heads is different form that in no recording/reproducing period. CONSTITUTION:The rotational angular velocity of the rotary heads 2a, 2b is controlled so that the rotational angular velocity of the heads 2a, 2b in the recording/reproducing period of the magnetic tape 21 based upon the magnetic heads is different from that in no recording/reproducing period. For instance, the rotational velocity of the rotary heads 2a, 2b are controlled so as to be different between the opposite contact of the heads 2a, 2b with the magnetic tape 21 and no opposite contact and a horizontally synchronizing frequency of a TV signal supplied to the heads 2a, 2b is set up to a high value corresponding to the angular velocity of the heads 2a, 2b. Thus, even when a loading angle is different, the loci of the rotary heads 2a, 2b on the magnetic tape 21 can be set up to optionally shapes.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a tape device for recording and reproducing information signals, and in particular, to maintain compatibility of a tape-shaped recording medium at a plurality of tape transfer speeds and to reduce the size of the device. It measures the

(Prior Art) In recent years, many systems such as tape devices and disk devices have been proposed as means for recording and reproducing various types of information.

Generally used as a tape device for high-density recording.

A magnetic recording method using magnetic tape is often adopted, and the so-called helical scan method is a method in which two rotating heads are attached to a tape guide drum and these rotating heads record video signals on the magnetic tape at high density. It has been adopted.

However, in such a helical scan method, the diameter of the tape guide drum of, for example, a rotating two-head VTR must have a predetermined diameter.

When attempting to downsize a VTR device, particularly to make it portable, the most important issue is the diameter of the tape guide drum.

Generally, the larger the diameter of the tape guide drum, the greater the amount of information that can be recorded, but this leads to an increase in the size of the device.

Therefore, many methods have been proposed in the past in order to record and reproduce a large amount of information without increasing the diameter of the tape guide drum.

For example, without increasing the diameter of the tape guide drum,
As a means of recording large amounts of information,
A method such as that shown in No. 06 has been proposed.

The conventional technology will be explained below based on the drawings.

FIG. 8 is a diagram showing an example of the configuration of a conventional video signal recording device. In the figure, a tape guide drum 1 rotates at a frequency of 59.94 Hz, and its diameter is the same as that of an ordinary rotating two-head type tape guide drum 1. It has been downsized to approximately 60% of its diameter. Two rotary heads 2a and 2b (see FIG. 9) are attached to this tape guide drum 1 in close proximity to each other as will be described later. The direction of rotation of the tape guide drum 1 is indicated by an arrow 1a, and the direction of movement of the magnetic tape 21 is indicated by an arrow 1b.

Magnets 5a and 5b are attached to the rotating shaft 4 of the drum motor 3 at positions corresponding to these rotating heads 2a and 2b. The rotary heads 2a and 2b are attached by first providing the rotary heads 2a and 2b on the same head substrate at the same height and spaced apart from each other by a predetermined distance, and then attaching this head substrate to the tape guide drum 1.

Further, the rotation of the rotating shaft 4 is transmitted to the capstan 6 by a pulley, a flat belt, etc.

The rotation of the rotating shaft 4 is detected by a detection element 7a arranged to face the magnets 5a and 5b, respectively.

7b.

That is, the output of the detection element 7a is supplied to the set terminal S of the flip-flop 9 via the amplifier 8a, and the output of the detection element 7b is supplied to the reset terminal R of the flip-flop 9 via the amplifier 8b.

Further, the output phase of the amplifier 8a is compared with the phase of the output from the reference oscillator 11 by a phase comparator 10, and the comparison output is supplied to the drive amplifier 12 of the drum motor 3 in order to control the rotational speed of the tape guide drum 1. do.

Further, the normal output of the flip-flop 9 is supplied to the synchronous board 13.

This synchronization board 13 creates a vertical synchronization signal VD and a horizontal synchronization signal HD from the regular output of the flip-flop 9, respectively, and the deflection system of the television camera 14 is driven by these synchronization signals. This television camera 14 creates a television signal consisting of a vertical synchronization signal, a horizontal synchronization signal, and an image, supplies the Y signal (luminance signal) in the television signal to a viewfinder 15, and sends an FM signal by an FM modulator 16. The signal is modulated and supplied to the adder circuit 17. On the other hand, as an input to this adder circuit 17, a low-frequency converted chroma signal is supplied.

As will be described later, since the horizontal synchronization frequency in the Y signal is set higher than usual, the frequency of the carrier wave for low frequency conversion of the chroma signal is also increased.

The pattern of carrier waves recorded on the magnetic tape is the same as in the prior art. And the above-mentioned addition circuit 1
7 is supplied to switch circuits 18 and 19. In this case, the normal output of flip-flop 9 is “1” or 11
0'', the switch circuit 18 or 19 supplies the output of the adder circuit 17 to the rotary head 2a or 2b.The normal output of the flip-flop 9 is also supplied to the control signal recording head 20.

Hereinafter, the operation of the conventional example which is ovalized as described above will be explained.

FIG. 9 shows the arrangement of the rotary heads 2a and 2b in FIG. 8, and the winding angle of the magnetic tape 21 with respect to the tape guide drum 1 is a (a4300'), α=2π-a,
Let β be the angular interval between the rotating heads 2a and 2b. Now, the rotating head 2 is attached to the magnetic tape 21 as shown in FIG. 9(A).
When a starts to come into contact with each other, the detection element 7a detects a signal from the magnet 5a provided at a position corresponding to the rotary head 2a, and sends a pulse as shown in FIG. 10A to the flip-flop 9 via the amplifier 8a. Supplied to set terminal S.

At this time, the normal output of the flip-flop 9 becomes "1" as shown in FIG. 10C, and the output of the adder circuit 7 is supplied to the rotary head 2a via the switch circuit 18. At this time, the length L of the recording track ta recorded by the rotary head 2a as shown in the 10th diagram corresponds to the winding angle a of the magnetic tape 21 with respect to the tape guide drum 1.

Next, as shown in FIG. 9(B), when the rotary head 2b begins to come into contact with the magnetic tape 21, the detection element 7b detects a signal from the magnet 5b provided at a position corresponding to the rotary head 2b. A pulse as shown in FIG. 10B is supplied to the reset terminal R of the flip-flop 9 via the amplifier 8b.

At this time, the normal output of the flip-flop 9 becomes '0'' as shown in FIG. 10C, and therefore the complementary output is rr I I
It becomes +. Therefore, the output of the adder circuit 17 is supplied to the rotary head 2b via the switch circuit 19.

Then, the rotary head 2b forms a recording track tb of length tb as shown in FIG. 10E. Here, the length Ll from when the rotary head 2a leaves the magnetic tape 21 to when the rotary head 2b comes into contact with the magnetic tape 21 is shown in FIG.
) As is clearer, it corresponds to the angle α−β.

Next, as shown in FIG. 9(C), the rotary head 2b leaves the magnetic tape 21, the rotary head 28 comes into contact with the magnetic tape 21, and a recording track ta is formed by the rotary head 2a. Head 2b is magnetic tape 2
1, the length from when the rotary head 2a comes into contact with the magnetic tape 21 again is r, and 2 corresponds to the angle α+β, as is clear from FIG.

In the 10th diagram or E, the shaded area indicates the recording track ta or tb through the rotary head 2a or 2b.
The lj direct synchronization signal recorded in is shown. The vertical deflection signal of the television camera 14 corresponding to this vertical synchronization signal is as shown in FIG. 10F. That is, the period Ta during which all recording signals are supplied to the rotary head 2a corresponds to the angle a+α−β,
Further, the period Tb during which the signal to be recorded is supplied to the rotary head 2b corresponds to the angle a+α+β, and has different lengths.

The period Ta+Tb is the length of one frame period.

Also, the number of horizontal synchronization signals recorded on recording tracks ta and tb is 262.5, and these recording tracks ta,
Since there is a horizontal synchronization signal within one frame period other than tb, the horizontal synchronization frequency is approximately 20 in the case of a normal television signal (262.5 horizontal synchronization frequencies are included in one vertical period). % higher.

As described above, the tape guide drum 1 is approximately 6011z.

In other words, although the magnetic tape rotates at a rate of one rotation in the time corresponding to one field of the television signal, since the horizontal synchronization frequency of the television signal supplied to the rotary drum is set high, the magnetic tape does not reach the tape guide drum. In the contact area, a video signal (262,5 horizontal signal sections) for one field of a normal television signal is recorded on the magnetic track.

That is, the magnetic pattern recorded by this recording device is
The magnetic pattern can be similar to the magnetic pattern of a commonly known rotating two-head type VTR.

Number of horizontal synchronizing signals 11a in period Ta, period Tb
Let Hb be the number of horizontal synchronization signals in , then Ha ==
a + (Z-β

Recording track ta recorded as described above.

FIG. 11 shows the position of the magnetic tape 21'' of tb. In the recording track of FIG. 11, the shaded area indicates a vertical synchronization signal.

At this time, the black and white effective screen 2 by the viewfinder 15
2 is shown in FIG. Here, horizontal scanning lines are schematically shown using solid lines and broken lines, the solid line showing the horizontal scanning line during the period Ta, and the broken line showing the horizontal scanning line during the period Tb.

As shown in FIG. 12, the signal of one field corresponding to the winding angle a of the magnetic tape 21 on the tape guide drum L is on the effective screen 22, but the lengths Ll and L in FIG.
The portion corresponding to l is outside the effective screen 22.

Now, the number of horizontal scanning lines corresponding to the winding angle a of the magnetic tape 21 wound around the tape guide drum 1 is 262.5, and the number of horizontal scanning lines corresponding to the angle α on the invalid screen is m (positive ), and the number of horizontal scanning lines corresponding to the angle β is n (negative integer). When Ta is one period, the number of horizontal scanning lines in the invalid screen is m-n as shown in Figure 12. , and the number of horizontal scanning lines in the invalid screen during period Tb is m + n.

The magnetic tape 21 recorded azimuthally in this manner is then played back by a normal two-head VTR device having a rotating tape guide drum with an angular spacing of approximately 180" and 301 [z between the rotating heads. In this case, the playback The rotary heads for the recording medium are configured to scan over the recording tracks ta and tb, respectively.

By the way, the winding angle a of the magnetic tape 21 with respect to the tape guide drum 1 rotating at approximately 6011z in FIG. 8 is 3.
Considering the relative speed between the one-rotation head and the magnetic tape, the diameter of the tape guide drum 1 may be approximately 1/2 of that of the tape guide drum of a normal two-head VTR.

(Problem to be Solved by the Invention) However, in such a system, the relative speed between the heads 2a, 2b and the magnetic tape 21 is essentially 1.
Since the 80 degree wrap is different from that of a regular VTR, several problems arise.

Hereinafter, a VH8 system VTR in the NTSC broadcasting system, which is popular as a home VTR, will be explained as an example. For example, in the standard mode, the tape transport speed is increased to increase the track pitch in order to improve the S/N ratio, and in the standard mode, the transport speed is reduced to reduce the amount of time consumed when the tape is lit. There is also a long-time mode that reduces the track pitch. VTR devices that have both of these two operating modes are generally in widespread use.

Table 1 shows the tape format of the VH8 system. As shown in the table, in the VH3 system, the angle of the track recorded on the magnetic tape with respect to the longitudinal direction of the magnetic tape,
The so-called track angle is 5' in the target mode.
58'9.9", while in long time mode,
5"56'48.2".

These values are the diameter of the tape guide drum 1, the angle of the lead groove provided on the tape guide drum with respect to the rotating plane of the rotating head (hereinafter abbreviated as lead angle), the winding angle of the magnetic tape, and the magnetic tape per unit time. It is uniquely determined by the transfer speed.

However, in the system shown in Japanese Patent Publication No. 60-51306, if the winding angle of the magnetic tape and the moving speed of the magnetic tape per m open time are determined, the tape guide drum 1 is required to obtain the same track angle as the VHS format.
The diameter and lead angle are uniquely determined for both the standard mode and long-time mode.

For example, when the winding angle of the magnetic tape around the tape guide drum is 300 degrees, the diameter and lead angle of the tape guide drum corresponding to the standard mode or long time mode take values as shown in Table 2.

Generally, information recording devices are particularly required to be compatible with each other, and tape devices are required to have a deviation amount in the track width direction below a certain value.

However, according to Table 2, when the magnetic tape is wound 300'' around the tape guide drum, the difference in lead angle between standard mode and long-time mode is approximately 13.5'', which is converted into a deviation in the track width direction. Then it becomes about 6.4-. Therefore, the magnetic tape is placed on the tape guide drum using 300B.
Wind it around and set the lead angle to 5, for example, corresponding to the standard mode.
With the device set to ``56'27.7'', the magnetic tape transfer speed is set to 11.12m+/, which corresponds to the long-time mode.
The magnetic tape transferred and recorded in sec is φ62nvn,
When played back on a deck equipped with a two-head tape guide drum, a track shift of about 6.4 IIm will occur. This means that when the track width is small, such as in long-time mode, the S/N ratio will deteriorate, resulting in a deterioration of the image quality.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a system for rotating the rotary head so that the rotational angular velocity of the rotary head is different between a period in which the rotary head records and reproduces data on a magnetic tape and a period in which it does not perform recording and reproducing on a magnetic tape. It is an object of the present invention to provide a control means for controlling the rotational angular velocity so that the track angle becomes a predetermined value in both the long-time mode and the target Y (Q mode).

(Function) The present invention includes a control means for controlling the rotational angular velocity of the rotary head so that the rotational angular velocity of the rotary head is different between a period when the rotary head records and reproduces information on a magnetic tape and a period when it does not perform recording and reproduction on a magnetic tape. Even when the lead angles are different, the rotation locus of the rotary head on the magnetic tape can take any shape. That is, even if the lead angle is set to an angle corresponding to the standard mode, it is possible to make the recorded track angle match the track angle defined in the long time mode format.

Therefore, the diameter of the tape guide drum of a rotating two-head VTR type VTR is reduced to make the VTR more compact, and moreover, recording is performed in the same recording format (azimuth recording) as in the above-mentioned rotating two-head type VTR. Moreover, even if recording is performed at a plurality of tape transport speeds, it is possible to obtain a track angle determined for format 1-.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a block diagram during a recording operation of a tape device in an embodiment taking the VH8 system as an example.

In FIG. 1, the time period required for one rotation of the tape guide drum 1 is L 159.94 seconds, and its diameter is approximately 6 times the diameter of a normal rotating two-head type tape guide drum 1.
It has been made 37.165nwn, which is equivalent to 37.165nwn.

The lead angle is set to 5°56'27.7''.

This tape guide drum 1 has two rotating heads 2a and 2b.
are mounted close to each other as shown in FIG. The direction of rotation of the tape guide drum 1 is indicated by an arrow 1a, and the direction of movement of the magnetic tape 21 is indicated by an arrow 1b. An encoder 70 is integrally attached to the rotating shaft 4 of the drum motor 3 so as to be in a predetermined phase with the rotating heads 2a, 2b. The method for attaching the rotary heads 2a and 2b is to first install the rotary heads 2a and 2b on the same head substrate (not shown) at the same height and separated by a predetermined distance, and then attach the head substrate to the tape guide drum. Attach to 1.

Note that in order to drive the capstan 6, the drum motor 3
Separately, a capstan motor 30 is directly attached to the capstan 6.

Here, the tape transport speed information 110 is given to the capstan motor drive amplifier 64 via the phase angular velocity information memory 100 and the velocity phase comparator 740, and the capstan motor 30 rotates the capstan 6 at a constant angular velocity.

Here, the capstan 6 cooperates with the pinch roller 120 to transport the magnetic tape 21 at a constant speed.

On the other hand, an encoder 71 is integrally attached to the capstan 6, the rotational angular velocity and rotational phase of the capstan 6 are detected by a speed phase detector 62, and this speed phase information is fed back to a speed phase comparator 740.

The rotational angular velocity and rotational phase of the tape guide drum 1 are detected by the encoder 70, and the encoder output is inputted to a speed phase comparator 74 via a speed phase detector 72. Here, the tape transport speed information 110 allows predetermined memory information in the phase angular velocity information memory 100 to be selected. This memory information consists of reference information of the rotational speed corresponding to the tape transport speed and the rotational phase of the tape guide drum 1.

The output of the speed phase detector 72 is inputted to a speed phase comparator 74, and is further input to the drive amplifier I2 of the drum motor 3.
The rotation of the drum motor 3 is controlled so that the rotation angular velocity of the tape guide drum 1 becomes a predetermined value corresponding to the rotation phase.

Here, the instantaneous rotation speed of the drum motor 3 is expressed as f! as shown in Table 3. Regardless of phase in mode: 3
It is 5416.4 rpm. On the other hand, in the long-time mode, the :too' interval is 5971.63 rpm, 60
'' section rotates at 1203.31 rpm. However, the time required for the tape guide drum 1 to rotate once in both the standard mode and the long time mode is 1159.94 seconds.

In addition, a velocity phase detector 72 and a phase angular velocity information memory 10
The output of 0 is supplied to the synchronous board 13. This synchronization board 13 creates a vertical synchronization signal VD and a horizontal synchronization signal HI) corresponding to the rotational phase of the tape guide drum based on the outputs of a velocity phase detector 72 and a phase velocity information memory 100, and these synchronization signals are used to generate a television camera 14. deflection system is driven. This television camera 14 creates a television signal consisting of a vertical synchronization signal, a horizontal synchronization signal, and an image, and supplies the Y signal (l11 degree signal) in the television signal to a viewfinder 15, and uses an FM modulator 16 to
The signal is modulated into a signal and supplied to the adder circuit 17. On the other hand, as an input to this adder circuit 17, a low frequency converted C signal (chroma signal) is supplied.

As shown in Table 3, the horizontal synchronization frequency in the Y signal is higher than normal, so the frequency of the carrier wave for low frequency conversion of the chroma signal is also increased, and the carrier wave recorded on the magnetic tape is The pattern is the same as before. Then, the output of this adder circuit 17 is transferred to a switch circuit 18.
Supply to 0. Then, depending on the output of the synchronous disk 13, the output of the adder circuit 7 is alternately supplied to the rotary heads 2a and 2b. The output of this synchronous disk 13 is supplied to a control signal recording head 20.

The operation of this embodiment configured as described above will be described below.

In FIG. 2, the winding angle of the magnetic tape 2 with respect to the tape guide drum 1 is a (a phrase 300'),
α=2π−a1 The angular interval between the rotating heads 2a and 2b is β
shall be. , when the rotating head 2a starts to come into contact with the magnetic tape 21 as shown in FIG. 2(A), the encoder 70 detects the signal shown at the position corresponding to the rotating head 2a, and the encoder 70 detects the signal shown in FIG. 3A. Such a pulse is supplied to a set terminal (not shown) of a flip-flop (not shown) provided in the velocity phase detector 72.

At this time, the normal output of the flip-flop becomes 11'' as shown in FIG. The length L of the recording track ta as shown in the third diagram is the length L of the tape guide drum 1.
The winding of the magnetic tape 21 around the angle corresponds to the angle a.

Next, as shown in FIG. 2(B), when the rotary head 2b starts to come into contact with the magnetic tape 21, the encoder 70 detects a signal indicating the position corresponding to the rotary head 2b, and as shown in FIG. The pulse is sent to a reset terminal (not shown) of a flip-flop (not shown) provided in the speed phase detector 72.
supply to.

At this time, the normal output of the flip-flop becomes ``0'' as shown in FIG. 3C, and therefore the supplementary output becomes 1''. Therefore, the output of the adder circuit 17 is supplied to the rotary head 2b via the switch circuit 180. Then, a long recording track tb as shown in FIG. 3E is formed by the rotary head 2b. Next, the length Ll from when the rotary head 2a leaves the magnetic tape 21 to when the rotary head 2b comes into contact with the magnetic tape 21 is determined by the angle α-
It corresponds to β.

Next, as shown in FIG. 2(C), the rotating head 2b separates from the magnetic tape 1 and the rotating head 2a comes into contact with the magnetic tape 21, and the recording track ta is formed by this rotating head 2a. The rotating head 2b separates from the magnetic tape 21 and the rotating head 2a returns to the magnetic tape 2.
As is clear from FIG. 2, the length Ll until it comes into contact with 1 corresponds to the angle α+β.

Further, the rotational speed of the rotary head is controlled so that it takes different values in the long-time mode when the rotary heads 2a, 2b are in contact with the magnetic tape 21 and when they are not in contact with the magnetic tape 21. In this embodiment, the rotational angular speeds of the standard mode and long-time mode are set as shown in Table 3.6 Here, the rotational speed of the drum in the long-time mode is set as:
The reason for setting as shown in the table is as follows.

FIG. 4 shows the formation of a tape pattern in this example. Here, ■ and G indicate the lead grooves of the tape guide drum 1, and TS and TL are tracks defined in the standard mode and long time mode formats, respectively. Also T17
．． Wrap the tape on this tape guide drum, and set the number of rotations of the tape guide drum 1 to a constant rotation speed of 3596.4.
rpm, and the tape transport speed is set to the long-time mode speed 1], , 12 nwn/sec.

As is clear from the figure, the amount by which the tape is transported during one rotation of the tape guide drum 1 is the value obtained by dividing the tape transport speed by the frequency of the vertical synchronization signal. Here, the lead angle is fixed at 5°56'27.7", so if the rotational speed of the tape guide drum tx1 is constant in the marking mode, the track angle is 5°58'9.9". ”, which corresponds to the value of V FI S (7) standard mode.

However, when the rotational speed of the tape guide drum 1 is kept constant in the long-time mode, the trunk angle is 5°57'1.
7”, and the original long-time mode track angle is 5°56.
The difference from '4L2' is 13.5".

Therefore, in order to eliminate this difference, the magnetic tape 21 should be 0.0
93417nni It is necessary to rotate the tape guide drum 1 by 300 degrees during the transfer. That is, if the rotational speed N i (rpm) of the tape guide drum 1 in the 300° section is set, the same track angle as the track T L in the long-time mode is obtained. The time T300 required for the tape guide drum 1 to rotate 300 degrees is as follows.

Also, since the time required for one revolution of the tape guide drum 1 is 1159.94 seconds, the 60° section in which the tape guide drum 1 does not record is 8.3]04 (=100015
9.94-8.3729) It is necessary to rotate at m5ec. The rotational speed N2 in this 60° section is N2=60X-X-knee=1203.3rpm360
It is necessary to set it as 8.3104.

The instantaneous rotational speeds in the long-time mode and standard mode are shown in FIG. As mentioned above, in the standard mode, it is driven at a constant rotational speed, and in the long-term mode, the speed is changed according to the phase to obtain a predetermined track angle.

Next, in the third diagram or E, the shaded area is the recording track ta or t through the rotary head 2a or 2b.
The vertical synchronization signal recorded in b is shown. The vertical deflection signal of the television camera 14 corresponding to this vertical synchronization signal is shown in FIG.
It becomes as shown in . That is, the periods Ta and Tb during which signals to be recorded are supplied to the rotary heads 2a and 2b correspond to the angle a, and both have the same length. That is, when the rotary heads 2a, 2b are not recording, the vertical synchronization signal and the horizontal synchronization signal are stopped.

Further, Ta+Tb is the length of one frame period, and the number of horizontal synchronization signals recorded on recording tracks ta and tb is 262.5, respectively.
Considering that horizontal synchronization signals apparently exist within one frame period other than tb, in the case of a normal television signal (262.5 horizontal synchronization signals are included within one vertical period).

), the horizontal sync frequency is approximately 20% in standard mode,
It is set to be 99% higher in long-term mode.

As mentioned above, the rotation speed of the rotating head is
The rotation of the rotating heads 2a and 2b is controlled to take different values when they are in contact with each other and when they are not in contact with each other, and the horizontal synchronization frequency of the television signal supplied to the rotating heads is adjusted to correspond to the angular velocity of the rotating heads. Set it high.

Therefore, in the area where the magnetic tape is in contact with the tape guide drum 1, the video signal for one field of the normal television signal (262,5 horizontal signal sections) is converted into formats with different tape transport speeds. It can be formed on matched magnetic tracks. That is, the magnetic pattern recorded by this recording apparatus can be made similar to the magnetic pattern of a commonly known rotating two-head type VTR.

Recording track ta recorded as described above.

The position of tb on the magnetic tape 21 is shown in FIG. In the recording track in FIG. 6, the shaded area indicates a vertical synchronization signal.

At this time, the black and white effective screen 2 by the viewfinder 15
2 is shown in FIG. Here, horizontal scanning lines are schematically shown using solid lines and broken lines, the solid line showing the horizontal scanning line during the period Ta, and the broken line showing the horizontal scanning line during the period Tb.

As shown in FIG. 7, the signal of one field corresponding to the winding angle a is on the effective screen 22, but the length L in FIG.
Vertical synchronization and horizontal synchronization are stopped in the portions corresponding to I and I2.

The magnetic tape 21 recorded in this manner is then reproduced by an ordinary rotary two-head type VTR device having a tape guide drum that rotates at 30)1z with an angular spacing of approximately 180 degrees between the rotary heads. In this case, the reproducing rotary heads are configured to scan over recording tracks ta and tb, respectively.

By the way, the wrapping angle a of the magnetic tape 21 with respect to the tape guide drum 1 rotating at approximately 60 Hz in FIG. 1 is approximately 30 Hz.
0@, so considering the relative speed between the one-rotation head and the magnetic tape, the diameter of this tape guide drum 1 can be approximately 60% of that of the tape guide drum of a normal two-head VTR. In the embodiment, the capstan motor 30 is directly attached to the capstan 6, but it is obvious that the capstan 6 may be rotated by the drum motor 3 via a flat belt or the like. Further, although the embodiment takes the VIIS format as an example, it is obvious that the present invention can be applied to other tape formats as well.

(Effects of the Invention) As explained above, the present invention is capable of controlling the rotational angular velocity of the rotary head so that the rotational angular velocity of the rotary head is different between the period in which the magnetic head records and reproduces data on a magnetic tape and the period in which it does not. Therefore, even if the lead angles are different, the locus of the rotary head on the magnetic tape can take any shape. In other words, even if the lead angle is set to the angle corresponding to the standard mode, the set track angle will be changed to the track angle specified in the long mode format.
M can be matched.

Therefore, the diameter of the tape guide drum of a one-rotation, two-head VTR type VTR is made smaller to make the VTR smaller, and it is possible to record in the same recording format (azimuth recording) as that of a two-rotation, two-head type VTR, and to record multiple types of tape. Even when recording is performed at the tape transport speed, the track angle defined in the format can be followed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a video signal recording apparatus according to the present invention, and FIG. 2 shows a rotary head 2a attached to the tape guide drum 1 in FIG. 2b is a diagram showing the arrangement relationship in FIG. 2b, FIG. 3 is a diagram for explaining the operation of FIG. 1, and FIG. FIG. 515th! ? 6 is a diagram showing the rotational speed of the tape guide drum according to this embodiment, FIG. 6 is a diagram showing the magnetic tape 21 recorded by the video signal recording device according to this embodiment, and FIG. 7 is a diagram showing the viewfinder 15 in FIG. 1. A diagram showing the relationship between both surfaces 22 and horizontal scanning lines, FIG. 8 is a configuration diagram of a conventional video signal recording device, and FIG. 9 is a diagram showing the tape guide drum 1 in FIG.
A diagram showing the arrangement of rotating heads 2a and 2b attached to the
Fig. 10 is a diagram for explaining the operation of Fig. 8;
This figure shows a magnetic tape 21 recorded by a conventional video signal recording apparatus, and FIG. 12 is a diagram showing the relationship between both surfaces 22 of the viewfinder 15 in FIG. 8 and the horizontal scanning line. 1... Tape guide drum, 2a, 2b... Rotating head, 3... Drum motor. 4...rotating shaft, 6...capstan, 12.
64...Drive amplifier, 13...Synchronization board, I4...
TV camera, I5... Viewfinder, 1
6... FM modulator, 17... Adding circuit, 20...
・Control signal recording head, 21... Magnetic tape, 30... Capstan motor, 62.72...
Velocity phase detector, 70.71... encoder, 74.
740... Speed phase comparator, 100... Phase angular velocity information memory, 110... Tape transport speed information, 12
0...Pinch roller, 180... Switch circuit. Patent applicant Matsushita Electric Industrial Co., Ltd.

Claims (1)

[Claims] When a tape is wound over a predetermined angle around a tape guide drum equipped with a rotating head and information signals are recorded and reproduced on the tape by the rotating head, a period of recording and reproduction;
A tape device characterized in that the rotational angular velocity of the rotary head is controlled so that the rotational angular velocity of the rotary head is different between periods in which recording and reproduction are not performed.