JPS6057505A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To extend a recordable band without increasing the diameter of a head cylinder by supplying independent signals of respective magnetic heads while plural magnetic head provided on the head cylinder are brought into contact with a magnetic tape in a reproducing device of the helical scan system. CONSTITUTION:A head cylinder 2 is provided with magnetic heads 3, 4, 5 and 6 on the same rotative face, and an erasing head 9 is provided to precede the magnetic head 6. Azimuth angles of magnetic heads 3 and 5 are equal to each other, and those of magnetic heads 4 and 6 are equal to each other, but azimuth angles of magnetic heads 3 and 5 are different from those of magnetic heads 4 and 6. A magnetic tape 1 is wound spirally around the outside circumference of the head cylinder 2 at >=270 deg. by tape guides 7 and 8 and is run. Recording tracks are formed in the order of tracks CH6, CH5, CH4 and CH3 by magnetic heads 6, 5, 4 and 3 and signals A, B and C are recorded in order on respective fields of each recording track, and thus, recording and reproducing of wide-band signals are possible without increasing especially the diameter of the head cylinder 2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a helical scan type i&magnetic recording/reproducing apparatus equipped with a plurality of magnetic heads, and particularly to a magnetic recording/reproducing apparatus capable of wideband recording.

[Background of the invention]

In recent years, helical scan video tape recorders (
Regarding VTRs (hereinafter referred to as VTRs), whether for home use, business use, or broadcasting, there is an increasing demand for further improvement in the image quality of the reproduced image fco ξ. Since a new broadcasting system that targets high-definition images with a large number of images has been proposed, it has become necessary to be able to record and reproduce the broadcast signals of such a new broadcasting system.

For this reason, the recordable frequency band of VTRs must be expanded more and more, and one way to do this is to increase the relative speed between the magnetic head and the magnetic tape. To achieve this, it is necessary to increase the rotational speed while keeping the rotational speed of the magnetic head constant.
The diameter of the head cylinder on which the magnetic head is mounted must be made thicker. However, if the diameter of the head cylinder is made thicker, the VTR itself will naturally become larger and its weight will also increase. Going against the trend of smaller size and lighter weight, the V
This is not a good thing for TR.

On the other hand, by installing a large number of magnetic heads on a head cylinder and switching between these magnetic heads in sequence, the relative speed between the magnetic head and the magnetic tape can be increased without increasing the diameter of the head cylinder. V'l"
I-L was proposed.

FIG. 1 is a plan view showing the head cylinder section of such a conventional magnetic recording and reproducing device, in which 1 is a magnetic tape, 2 is a head cylinder, 3, 4, 5.6 are magnetic heads, and 7.8 is a tape guide. It is.

In the figure, magnetic heads 3, 4, and 5.6 are arranged at equal intervals of 90° on the outer circumference of a head cylinder 2, and the magnetic tape 1 is transferred to the head cylinder 2 by a tape guide 7.8. The winding runs in a helical manner over at least 270° around the outer periphery of. For this purpose, the magnetic head 3
, 4, 5 and 6 each scan the magnetic tape 1 by 3/4 rotation.

The wrapping angle of the magnetic tape 1 around the head cylinder 2 is now 27.
0°, the magnetic tape 1 runs in the direction indicated by the arrow, and the head cylinder 2 rotates in the direction indicated by the arrow Y. Then, each magnetic head 3, 4, 5, and 6 starts scanning the magnetic tape 1 from the point S. Then, scanning of the magnetic tape 1 ends at point E rotated by 270°, and this 270° scanning period is used as one part of the video signal.
Match field duration. Then, when the magnetic head 3 makes a 1/4 rotation after coming into contact with the magnetic tape 1 at point S, the magnetic head 6 reaches point S and comes into contact with the magnetic tape 1.
Furthermore, when the head cylinder 2 rotates 1/4, the magnetic head 5 reaches the point S and comes into contact with the magnetic tape 1. In this way, each time the head cylinder 2 rotates 1/4, the magnetic head 3 degrees rotates in the order of 3 degrees, 6.5 degrees, and 4 degrees. Scanning of the magnetic tape 1 is started.

Similarly, every time the head cylinder 2 rotates 1/4,
The magnetic heads 3, 6, 5.4 finish scanning the magnetic tape 1 at point E in this order, and start scanning the magnetic tape 1 again from point S.

Next, a method of recording the e@hakugo by such a head cylinder section will be explained.

Now, assuming that the magnetic head that reaches point S and starts scanning the magnetic tape 1 is the magnetic head 3, this magnetic head 3
From point S to point E-! One field of video signals is supplied and recorded during the 3/4 rotation period.

When the magnetic head 3 reaches point E, the magnetic head 4 reaches point SK.
has reached the magnetic head 4 during the next 3/4 rotation period.
Supplies and records field video signals. When the magnetic head 4 reaches point E, the magnetic head 5 has reached point S, and one field of video signals is supplied to the magnetic head 5 for the next 3/4 rotation period to record. In this way, each time the magnetic head that was performing a recording operation reaches point E, the magnetic head at point SK starts recording operation, and in the case shown, the magnetic heads 3.4, 5, 6.3', . . . The video signal is recorded field by field in the following order.

As a result, as shown in Fig. 2, on the magnetic tape 1,
Sequential recording tracks CH,, C'H4, CH5°CH,,
CH, . . . are formed with a track pitch P.

Note that the recording track CH3 is formed by the magnetic head 3, and will hereinafter be referred to as recording track CH.

CH, , CH, are formed by magnetic heads 4, 5, and 6, respectively.

In such a V Tlt, the head cylinder 2 rotates 3/4 during one field) tlJ, so it makes one rotation at 4/3 feed, whereas in a normal VTR equipped with two magnetic heads, So, the head cylinder is 2
Since the field rotates once, the number of revolutions is 1.5 times larger than that of this normal helical scan method v'rl.Therefore, the VTR described above is different from the normal VT.
If the diameter of the head cylinder is equal to R, the relative speed between the magnetic head and the magnetic tape will be large, and wider band recording will be possible. can be made smaller, making it possible to be smaller and lighter.

However, although such conventional VTRs are equipped with a large number of magnetic heads, only one of them is in the recording operation, so only one channel of the signal is recorded. It is. Therefore, when considering color television (No. A is the recording power),
Due to the extremely slow running speed of magnetic tape for high-density recording, it has become necessary to record audio signals with a rotating head, and even more so. The signals are combined and supplied to the magnetic head. On the other hand, in order to further improve the reproduced image, it is necessary to widen the frequency band of the recording signal supplied to the magnetic head. In this case, the recorded signal has a much wider frequency band. Therefore, when recording multiple signals by frequency division multiplexing as in this prior art, the total frequency band of these signals is very wide, and if you try to widen the frequency band of these signals, In order to expand the recordable band by increasing the relative speed between the magnetic tape and the magnetic head, the diameter of the head cylinder becomes larger and the V
The drawback was that it was not possible to reduce the size and weight of the TR.

[Purpose of the invention]

An object of the present invention is to eliminate the drawbacks of the prior art described above, to sufficiently expand the recordable band without increasing the diameter of the head cylinder, to significantly improve the quality of reproduced images, and to achieve a compact and lightweight design. The present invention provides a magnetic recording and reproducing device.

[Summary of the invention]

In order to achieve this object, the present invention provides n magnetic heads (where n is an integer of 3 or more) at equal angular intervals on the outer periphery of a head cylinder, and also extends the outer periphery of the cylinder by at least 360° x ( It is wound spirally over an angular range of n 1 / n ) and run, m (however, m is 2
The recording signals of the above integer and genus m≦n are supplied to different magnetic heads for recording, and the magnetic head k (n'-1/n) for recording each recording signal
It is characterized in that it is switched every rotation, and the recording i= number is multi-channeled.

Therefore, the recordable band can be regulated by the frequency band of each recording signal to prevent widening of the band, and the diameter of the head cylinder can be made smaller accordingly.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 3(A) shows a head cylinder portion of an embodiment of the magnetic recording/reproducing device according to the present invention, FIG. 3(5) is a plan view thereof, and FIG. 3(13) is a side view thereof. , 9 is an erasing head, 10 is a rotating cylinder, and 11 is a fixed cylinder, and parts corresponding to those in FIG. 1 are given the same reference numerals.

In FIGS. 3A and 3B, magnetic heads 3, 4, . ．． 5.6 are provided, and an erasing head 9 is further provided preceding the magnetic head 6. The azimuth angles of the magnetic heads 3 and 5 are the same, and the azimuth angles of the magnetic heads 4 and 6 are also the same, but the azimuth angles of the magnetic heads 3 and 5 and the magnetic head 4°6 are different. 1 is wound spirally and runs over the entire outer circumference of the head cylinder 2 by a tape guide 7.8 over 270 degrees. The head cylinder 2 is a rotating cylinder 10
and a fixed cylinder 11, and this rotating cylinder 10
A magnetic head is attached to the magnetic head (FIG. 3 (+3) only shows the magnetic head 3). Actually, the rotating cylinder 10 rotates and the magnetic head 3. 4. 5. 6
scans the magnetic tape 1, and for the sake of simplicity, this is referred to as the rotation of the head cylinder 2.

Point S is the recording start position, point E is the recording end position, and the angle between points S and 8 is 270 degrees in the rotational direction of head cylinder 2 (arrow Y), and head cylinder 2 is 27
The period of 0° rotation, that is, the period of 3/4 rotation, is set equal to one field of the television signal. Therefore, the rotation period of the head cylinder 2 is equal to 4/3 of the field period of the television signal.For example, if the field frequency of the television signal is 59Hz, then the rotation period of the head cylinder 2 is equal to the field period of the television signal. This will be explained using figures.

Assuming that 381 type signals such as signal A, signal B, and signal C are to be recorded, in Fig. 4, Tyo is head cylinder 2.
0 rotation period, 'Pa is the field period. Also S,
is a signal supplied to the magnetic head 3, and hereinafter, s, ,
s, , s are signals supplied to heads 4, 5, and 6, respectively.

In FIG. 3(f), any three of the magnetic heads 3, 4, and 5.6 are always scanning the magnetic tape 1 in the section from point S to point E. Signal A is sent to each magnetic head.

Either B or C is supplied. Now, at time t0, if the magnetic head 6 to which the signal B is supplied reaches point E, the magnetic head 3 is at the point S, and the supply of the signal B is switched from the magnetic head 6 to the magnetic head 3.

At this time, the signal A is supplied to the magnetic head 4 which is 90 degrees ahead of the magnetic head 3, and the signal C is supplied to the magnetic head 5 which is further 90 degrees ahead of the magnetic head 3.

Next, when the head cylinder 2' rotates 1/4, the magnetic head 5 reaches point E, and the magnetic head 6 reaches point S. Then, when the signal C is supplied, the magnetic head 5 starts recording the signal C'(il-), the magnetic head 3 records the signal B gold, and the magnetic head 4 records the signal A.

In this way, when the head cylinder 2 further rotates by 1/4, the magnetic head 4 turns on, the magnetic head 5 reaches the point S, and the signal A is no longer supplied from the drowsy head 4 to the magnetic head 5.
Then, the signal A is recorded by the magnetic head 5.

When the head cylinder 2 further rotates by 1/4, the aerodynamic head 3 reaches point E and the magnetic head 4 reaches point S, and the supply of signal B is switched from the magnetic head 3 to the aerodynamic head 4. Time t. Since then, the head cylinder 2 has rotated 3/4, during which time the signal B for one field period Ill has been recorded by the magnetic head 3.

In this way, each time a magnetic head reaches point E, the signal that was being supplied to that magnetic head is switched to the magnetic head at point S, which is 90 degrees ahead of that magnetic head, and the next 3/3 It is recorded on the magnetic tape j during four rotations. So, there are three signals A and H.

C is continuously recorded by different magnetic heads.

In actuality, as shown in FIG. 3, the magnetic tape 1 is wound around the outer periphery of the head cylinder 2 by more than 270 degrees, and after each magnetic head passes point E, the signal is not transmitted for a while. is supplied, and each magnetic head is connected to the point S
The signal is already supplied before reaching , and for this purpose an overlap period δ (FIG. 4) is provided.

FIG. 5 is a pattern diagram showing recording tracks formed on the magnetic tape 1, where CH is a recording track by the magnetic head 3, CH4 is a recording tractor by the magnetic head 4, and CH is a recording track by the magnetic head 5. , CI(,
is a recording track by the magnetic head 6, and the same reference numerals are given to the parts corresponding to Fig. 3 (f).

FIG. 5 shows that the magnetic head 6 is at point 8 in FIG.
, shows the state at the time when the magnetic head 5 is at point E, and shows the moment when the signal C is switched from the magnetic head 5 to the magnetic head 6. δ is omitted). At this point, the magnetic head 3 has formed only 1/3 of the recording track CH5, and the magnetic head 4 has formed only 2/3 of the recording track CH4.

Therefore, from this point on, the magnetic head 6 begins to form the recording track CH6 for the signal C, and the magnetic head 4 begins to form the recording track CH6 for the signal A.
A recording track CH is formed by the signal B by the magnetic head 3.

In this way, the recording tracks Cl-16, C)1. , CH4, CH3
A recording trunk is formed in this order, and each signal is recorded in the order of signals A, B, and C for each recording track, one field at a time.

Now, assuming that the total width of three adjacent recording tracks is pitch P, the track width of magnetic heads 3, 4, and 5.6 is set slightly wider than V3, and the recording track formed by the preceding magnetic head is , the next magnetic head forms a recording track so as to partially overlap, and the width of the formed recording track is P/3. Further, since the azimuth angle of the magnetic head 3.5 and the azimuth angle of the magnetic heads 4 and 6 are different, the magnetization directions differ between adjacent tracks, and crosstalk between adjacent tracks during reproduction can be prevented. Furthermore, the track width of the erasing head 9 is made slightly wider than the pinch P so that a portion corresponding to the width of three recording tracks can be erased at the same time.

When a color television signal is to be recorded, the signals A, B, and C are the 几, G, and H signals, respectively, and the luminance signals Y and 2.
The color difference signals R, -Y, B-Y can be used as two color difference signals R, -Y, B-Y, or other component signals such as a luminance signal Y and chroma signals I and Q can be used.

In the prior art shown in FIG. 1, these signals A.

Combine B and C to create any one of the four magnetic heads.
However, in this embodiment, each can be recorded using separate magnetic heads. therefore,
The frequency band of the signals supplied to each magnetic head is narrower than in the prior art described above, and as a result, the diameter of the head cylinder 2 can be reduced. Also, in this example,
When using the head cylinder 2 with the same diameter as in the prior art described above, the frequency bands of each signal A, B, and C can be made wider. Therefore, when these are each component signal of a color television signal, It is possible to obtain high-quality reproduced images. In short, it is possible to record and reproduce broadband signals without particularly increasing the diameter of the head cylinder 2.

FIG. 6(A) is a block diagram showing a specific example of the recording circuit in the above embodiment, and FIG. 6(C) is a block diagram showing a specific example of the reproducing circuit. , 15.16.17 are reference pulse addition circuits.

18 is an index adding circuit, 19 is a distribution circuit, 20 is a tack signal generator, 21. , 22.23.24 is a frequency modulator, 25.26.27.28 is a recording amplifier,
29. '30.31.32 is a regenerative amplifier, 33 is a distribution circuit, 34 is a tack signal generator, 35.36.37 is a demodulator, 38 is a switching circuit, 39.40 is a variable delay circuit, 41.42.43 is a It is an output terminal, and 3,
4, 5.6 are the magnetic heads shown in FIG. 3 (G).

First, I will explain the recording circuit in FIG. 6(g).
Assume that the signal to be recorded is a color television signal, which is separated into primary color signals R, G, and B (hereinafter referred to as R signal, q signal, and B signal) and recorded. Therefore, the R signal corresponds to the signal A, the G signal corresponds to the signal B, and the B signal corresponds to the signal C.

R and G signals are output from input terminals 12, 13, and 14, respectively.

The B signal is supplied, and the reference pulse addition circuit 15, 16゜1
At 7, a pulse or bar for time axis alignment is added to the back porch of each horizontal retrace period, for example, a straight reference pulse. Figure 7 (5), @.

0 and a reference pulse Sb added to each IH (however, H
indicates the R, (3, B signals in the horizontal period). The JB signal to which the reference pulse has been added is supplied to the distribution circuit 19, and the q signal to which the reference pulse has been added is supplied to the index addition circuit 1.
8, for example, the vertical retrace period's one foot %41
A K index signal is added and supplied to the distribution circuit 19.

The tack signal generator 2o is connected to the head cylinder 2 (Fig. 3 (A).
A tack signal that is phase-synchronized with the rotation of )) is generated, and the distribution circuit 19 generates y(b) based on this tack signal.

The distribution circuit 19 distributes the 1t, G, and B signals to four channels, one field each, in synchronization with the tack signal.
The four signals shown in Fig. 4 when the signal A is the l(, signal, the signal B is the G signal, and the signal C is the B signal, s3゜S,'',
Ss, Ss full output. Ko'h, LaM No.Ss
, 84. ss.

S6 is modulated by frequency modulators 21, 22, 23; 24, amplified by recording amplifiers 2, 5, 26, 27, 28, and sent to magnetic heads 3.4', 5.6 at the timing shown in FIG. Supplied by R, G, B in distribution circuit 19
Signal distribution timing and image head 3, 4, 5°6
The relationship with the position of is explained earlier in relation to Figure 4,
The recording tracks formed on the magnetic tape are A and B.
The pattern shown in FIG. 5 is shown when G is G and C is B.

Next, the reproduction circuit shown in Fig. 6 σ) will be explained.

The magnetic heads 3, 4, 5, and 6 reproduce and scan recording tracks corresponding to azimuth angles using servo threads. The reproduction signals from the magnetic heads 3, 4, 5.6 are transmitted to the reproduction amplifier 2, respectively.
The signal is amplified at 9.30.31.32 and supplied to the distribution circuit 33. By the tack signal from the distribution circuit 33 and the tack signal generator 34, the distribution circuit 19 (FIG. 6 (c)))
The color signals for each field distributed by the distribution circuit 19 are combined by the reverse operation to generate reorganized R, G, . . . B signals. Regarding the R signal, the reorganization of the color signal by this distribution circuit 33 is as shown in FIG.
=A) is recorded on the recording track CH6 by the magnetic head 6.
When the magnetic head 6 is scanning for reproduction, the reproduction R of this magnetic head 6 is
The signal is output to, for example, the output line 33, and when the magnetic head 6 completes scanning this recording track CH, next, the magnetic head 3 reproduces the recording track CH in which the ratio signal is recorded. Since scanning is performed, the reproduced R signal of the magnetic head 3 is sent to the output line 33. Switching operation is performed to output the output. Similarly, when the magnetic head 3 finishes scanning the recording track CH of the R signal, the magnetic head 4 then scans the recording track CH of the R signal.
Furthermore, since the magnetic heads 5, 3, 4, 5, 6 sequentially reproduce the R signal one field at a time, the reproduced R signal one field at a time is transferred to the output line 33. The distribution circuit 33 operates to output the signal. Further, the magnetic heads 3, 4, 5.6 are R, , G, respectively.
Since the B signal is reproduced one field at a time, the magnetic heads 3, 4 . ! The G signal and B signal are reproduced one field at a time in the order of 5 and 6, and the distribution circuit 33 picks up the reproduction signals of the magnetic heads 3, 4, 5, and 6 and sends them to the output line 3.
3. It also picks up the B signal and outputs it to the output line 333.

J (
The r and B signals are demodulated by demodulators 35, 36, and 37, respectively, and supplied to a switching circuit 38.

By the way, the output line 33. KR ratio signal,
The G signal is not obtained on the output line 332 and the B signal is not obtained on the output line 333, but the distribution circuit 33
, 4, 5.6 JG from the reproduced signal.

Output line 33 according to the phase of pinking up the B signal,
, 33. ,．． 333, the color signals obtained are different. The switching circuit 38 switches Rl from the demodulators 35, 36, and 37 based on the index signal added to the G signal.
The Q and B signals are discriminated, and the R signal is always output to the output terminal 41.
Channel switching is performed so that the G signal is obtained at the output terminal 42 and the B signal is obtained at the output terminal 43.

In this case, the R signal is supplied to the variable delay circuit 39, and the B signal is supplied to the variable delay circuit 40, and is delayed by a predetermined amount.
, B signals are time-base aligned.

This time axis alignment is performed using a reference pulse S added to the G signal.
b (Fig. 7 (B)) as a reference, and the time difference between the rise of the reference pulse Sb of the R signal (Fig. 7 (A)) with respect to this rise, and the reference pulse Sb of the B signal (Fig. 7 (A)). This is done by detecting the time difference between the rises of 0) and setting the delay mk of the variable delay circuit 39 and 40 according to these time differences, so that the phases of the R and B signals match the phase of the G signal. .

In order to perform such time axis alignment, it is not necessarily necessary to use the above reference pulse, and it is also possible to omit the reference pulse by using the rising or falling edge of the horizontal synchronizing signal.

In the specific example of FIGS. 6(A) and (B), signal processing such as emphasis, clamping, clipping, de-emphasis, and dropout compensation for each color signal is also performed in lines C)', r
(iiff increased V T ]), the influence of the difference in each color signal at the time of head switching does not matter at all.

Of course, the configuration can be such that the head switching points for the It, G, and B signals are all set within the vertical retrace period.

In order to do this, if we assume that the head is switched during the vertical retrace period, the B signal corresponding to the signal C is sent to the head cylinder 2 (as is clear from FIG. 5). (see Fig. 3)) is delayed by a period corresponding to 1/4 of the rotation period TT1, and the R signal corresponding to signal A is similarly TI
It is sufficient to delay the period corresponding to I/2. Regeneration circuit (6th
In Fig. υ)), the G signal is delayed by T,/2, and the B
TI the signal! It is necessary to align the time axes of the G and B signals with a delay of /4.

Incidentally, in order to generate the overlap portion δ shown in FIG. 4, the start of recording is slightly earlier than point S, and the end of recording is slightly later than point E.

Furthermore, the audio <a> may be recorded in the longitudinal direction of the magnetic tape 1 (Fig. Make the corner sufficiently thicker than 270° (Figure 3 (A)
), 几, G, and B signals may be recorded in an overlapping portion before recording starts or after recording ends. This audio signal recording method is hereinafter referred to as an overlap recording method.

Furthermore, the tack signal generator 20 in FIG. 6(5) and the tack signal generator 20 in FIG.
The tack signal generator 34 of I3) is the same device.

FIG. 8(g) is a block diagram showing another specific example of the recording circuit in the embodiment shown in FIG.
44 is a block diagram showing another specific example of the reproduction circuit,
-48 are input terminals, and 49-53 are frequency modulators.

54. 55 is an addition circuit, 56 is a distribution switching circuit, 57.
58 is a high-pass filter, 59.60 is a low-pass filter, 61-65 are post-adjusters, 66-70 are output terminals, and 8F! Parts corresponding to FIGS. 6 (5) and (B) are given the same reference numeral t.

In this specific example, the signals to be recorded are a color preview signal and a stereo audio signal, and the color television signal is a luminance signal Y (hereinafter referred to as Y signal) and two color difference signals RY and B-Y (hereinafter referred to as Y signal). , respectively R-Y signal, B-Y
The stereo audio signal is obtained by frequency division multiplexing the left channel signal (hereinafter referred to as the AL signal) with the rt-y signal and dividing it into the right channel signal (hereinafter referred to as the A3 signal)'eB-Y signal. Recording is performed by frequency division multiplexing.

First, the recording circuit of 'd 8 IZI (A) will be explained.
The signal, R-Y signal, and B-Y signal are supplied to reference pulse addition circuits 15 and 16.17, respectively, and reference pulses are added thereto in the same manner as in the specific example of FIG. 6(g). It is modulated at 49,50°51. The frequency-modulated Y signal is supplied to an index adding circuit 18, an index signal is added thereto, and the signal is supplied to a distribution circuit 19. In this case, a pilot signal with a constant frequency is suitable as the index signal, and as is clear from Figure 9,
The frequency of this pilot signal P is set outside the frequency band of the frequency modulated Y signal (hereinafter referred to as F M (Y) signal).

On the other hand, the frequency modulated R-Y signal (hereinafter, 41% to F)
-Y,) signal) is supplied to the adder circuit 5.1, and the AL signal (hereinafter referred to as II''M(AL) signal) supplied from the input p1!6 child 47 and modulated by the frequency modulator 52. 1!'MCAL) signal frequency 'J range is set below the frequency band of FM (RY) signal,
Therefore, from the addition circuit 54 to the distribution circuit 19, the ninth
As shown in figure (IJ), FM (AL) signal and FM
A signal obtained by dividing the frequency division length IR of the (normal-Y) signal is supplied. Similarly, frequency modulated E −Y I @
signal (hereinafter referred to as the M(B-Y) signal), and an AR signal (hereinafter referred to as the FM(An) signal) supplied from the input terminal 48 and frequency modulated by the frequency modulator 53. is frequency division multiplexed in the adder circuit 55 as shown in Figure 9 (q) and is supplied to the distribution circuit 19.
Since the M (I also -Y) signal and the l;'M (B-Y) signal can have a sufficiently narrower limb numbering area than the FM (Y) signal, in this way, the F M (AL)'
1m issue.

It is possible to perform frequency division multiplexing with the Fh■(A4) signal.

The following is the same as the recording circuit shown in the 6th Q~-n, and 1! ” M (Yl signal and pilot signal P, which multiplexed signal is the signal A in Fig. 4, same <, F'M (R-Y)
The multiplexed signal of the signal and the i' M (A,,) signal corresponds to the signal B, and the multiplexed signal of the FM (1-3-Y) and FK'4 (AR) signals corresponds to iL'j +jC. The signals b3, b4, S5, shown in FIG.
S6 is obtained from the distribution circuit 19, and the self-recording increase 111'I
The signals are multiplied and subtracted by the N units 25, 26, 27, and 28 and supplied to the magnetic heads 3, 4, and 5.6, and each multiplexed signal is recorded for one field period at a time, as shown in FIG.

Next, to explain the reproducing circuit of Fig. 8 0), the 6th
The magnetic head 3°4.5.
The signals regenerated from 6 are sent to regenerative amplifiers 29, 30, .
31 and 32 and supplied to the distribution switching circuit 56.

Similar to the distribution circuit 33 in FIG. At the same time, each multiplexed signal is discriminated by the pilot signal PI+, and the FM (Y) signal is sent to the output line 56°, and the FM (H, -Y) signal and ii'M (
The multiplexed signal with the FM (B-AL) signal is sent to the output line 563.
A multiplexed signal of the Y) signal and the FM (AR) signal is output, respectively.

The FM (Y) signal is demodulated by a demodulator 61 and sent to an output terminal 66.
A Y signal is obtained. The high-pass filter 57 is
The low-pass filter 59 separates the M(RY) signal, and the low-pass filter 59
The high-pass filter 58 separates the FM (AL) signal.
(B-Y) signal and the low pass filter 60
(A,) Separate the signals. These F M (RY) signal, F'M (A,,) signal, F'M (B-Y) signal, and F'M (A,) signal are sent to demodulators 62, 63, and 64, respectively.
It is demodulated at ゜65, and At and (
ci, AI times signal is obtained. Also, the demodulated R-
The Y signal and the BY signal are respectively supplied to variable delay circuits 39 and 40, and the time axis is aligned with the Y signal using a reference pulse in the same manner as in the reproducing circuit of FIG. 6 (E3).

Therefore, the 1(, -Y signal, and B-Y signal whose time axes coincide with the Y signal are obtained at the output terminals 67 and 68, respectively.

Note that in the above specific example, the pilot signal P.

(See Figure 9)) can also be added only to the vertical retrace period of the FM (A) signal, in which case the influence of this pilot signal P on the FM (Y) signal is displayed. This does not occur within the screen, and a high-quality reproduced image can be obtained.

Furthermore, it is not necessary to record the audio signal by frequency division multiplexing the color difference signals R-Y and B-Y, but it is also possible to record the audio signal in the longitudinal direction of the magnetic tape, or by using the overlap recording method described earlier. It may also be recorded. Furthermore, the left channel signal AL.

The right channel signal A and the BY signal may be frequency division multiplexed and recorded.

Furthermore, the color television signal is the Y signal.

Although the recording is performed by dividing into the RY signal and the BY signal, the recording may be performed by dividing into the Y signal, I signal, and Q signal. The color television signal may be divided and recorded using other division methods. That-
As a specific example, the low frequency components Y1 . ．． The high-frequency component Y3 and the two color difference signals 1 (, -Y, B-Y are divided into YL-fold signal from the input terminal 44 and YY signal from the input terminal 45 in FIG. 8 (6),
Further, it is possible to supply line-sequential signals of the R-Y signal and the B-Y signal from the input terminal 46, and from the frequency modulator 49, the frequency modulation of the frequency spectrum shown in FIG. YL multiplied signal F M, (YL
) signal) is obtained, and the addition circuit 54 outputs a frequency-modulated YH times signal FM (Y
A frequency division multiplexed signal of the F1\4 (AL) signal) and the F1\4 (AL) signal is obtained, and from the adder circuit 55, the
As shown in , the line sequential signal (li'M (R-Y/B-Y)
A frequency division multiplexed signal of an FM (AR) signal and an FM (AR) signal is obtained.

In this way, recording and reproducing the color television signal by dividing it involves frequency-dividing the luminance signal, so it is possible to expand the entire frequency band of the luminance signal, and the number of scanning lines is lower than that of the current broadcasting system. This is particularly effective for broadcasting systems that have become high-definition by increasing the number of pixels.

Although the above example was about recording three types of signals, signals A, B, and C, it is also possible to record two types of signals.

Now, if these signals are called signals A and B, Fig. 3 (
In Fig. 11), which of the three magnetic heads scanning the magnetic tape 1 in an angular range of 270° from point S to point E performs recording by two magnetic heads, as shown in Fig. 11. As shown, recording tracks where signal A is recorded and recording tracks where signal B is recorded are alternately formed.

FIG. 12 shows each magnetic head 3 for performing such recording.
4,5. FIG. 4 is a timing chart showing signals supplied to "6", and each symbol corresponds to the symbol in FIG. 4.

Figure 3 GA), at the 12th y+, now time t0
is the base wall, and at this time t. Assume that the magnetic head 3 is at a point S. Assuming that the signal B has been supplied to the magnetic head 6 and the signal A has been supplied to the magnetic head 4 until just before this, time t. At , the signal B is switched from the magnetic head 6 to the magnetic head 3 (note that for the sake of simplicity, a description of recording in the overlap portion will be omitted).

After that, when the head cylinder 2 rotates 1/2, the magnetic head 4 reaches the point E, and the signal A is sent from the magnetic head 4 to the point SK.
The magnetic head 5 is switched to a certain magnetic head 5.

After the next quarter revolution, the magnetic head 3 reaches point E and the signal B is switched from the magnetic head 3 to the magnetic head 4 at point S.

Thereafter, every time the head cylinder 2 rotates 3/4, the signal A is switched from the magnetic head that has reached point E to the magnetic head 90 degrees ahead of it, and 1/4 times more than this switching of signal A. , and signal B is similarly switched.

Therefore, no signal is supplied to one of the three magnetic heads that scan the magnetic tape 1;
As shown in the figure, a guard band GB occurs every two recording tracks, and the recording track immediately before it (in the figure, the recording track where signal B is recorded) has another recording track overlapping a portion above it. Since no data is written, the width of the recording track is wider than the width of the recording track where the signal A can be completely recorded, and is equal to the track width of the magnetic heads 3, 4, and 5.6.

FIG. 13(g), 03) is a spectrum diagram showing a specific example of the signals A and B when the recording target is a color television signal.

In this specific example, as shown in FIG. As shown in (B)K in the same figure, a human being receives a frequency-modulated signal by time-division multiplexing the time-compressed R-Y signal and B-Y signal (hereinafter, this signal is referred to as a time-blend color difference signal). (Hereinafter, F'M (RY/B-Y
)t) and a frequency-modulated right channel signal 1''M(A, ).The time breech color difference signal is a mixture of the it-y signal and the B-Y signal, as shown in FIG. R-Y with IH period compressed to 1/2 and time-compressed into 4 periods (same as i4 <B-Yi with IH period compressed to H/2 period) Furthermore, as mentioned earlier, a reference pulse Sb for time axis alignment is added by the reference pulse addition circuit to the portion of the back porch in the horizontal retrace period. Of course, the same reference pulse Sb is added to the FM(1) signal in FIG. 13(g).

Note that in signal A in FIGS. 11 and 12, R-
The Y signal and the BY signal may be frequency modulated using separate carriers and frequency division multiplexed.

Further, as the tape running control means, means using control signals recorded in the longitudinal direction of the magnetic tape can be used, as in conventional VTRs, but the magnetic heads 3', 4. ．． 5.6, it is also possible to record the low frequency pilot ID@ for tracking and use this.

In other words, in FIG. 5, in the recording track where the signal A is recorded, a tracking pilot M with a frequency fPA set lower than the frequency band for the signal is set.
P A is recorded together with signal A, and similarly, signal B
On the recording track where is recorded, a tracking pilot signal P with a frequency fa11 set lower than the frequency band of Shingetsu B is added together with signal B, and also signal CiJ''
- In the recording track to be recorded, a tracking pilot signal P with a frequency fPc set lower than the frequency band of the signal C is recorded together with the signal C, and the frequencies f□, f□, fpc are different from each other −
5 and, for example, 1 fp, fpm 1 % 1 fpm - fpc l
By doing so, the track deviation li of each magnetic head can be determined from the difference in the amount of pilot signals reproduced from respective recording tracks adjacent on both sides of the recording trunk where signal B is recorded. To separate the reproduced pilot signals from the recording tracks adjacent on both sides,
As is well known, frequency fPB and frequency fPA
+fPe and the respective frequency differences may be utilized.

Also, such a tracking pilot signal PA.

P, , PC can also be used to identify whether the signal recorded on the recording track is signal A, B, or C. Fig. 15 shows the tracking pilot signal P.
The recording pattern of P,,PC is shown. For example, a filter is provided to extract each tracking pilot signal, and this filter determines the frequency of the tracking pilot signal (M) reproduced from the recording track currently being scanned, and from this, the frequency of the tracking pilot signal reproduced from the recording track currently being scanned is determined. The signal recorded on the recording trunk is number A,)3. C, or the signal currently being reproduced is the signal A, , B.
.

It can be determined which one is C.

Next, in this embodiment, a so-called overlapped PCM audio encoding/recording method will be described in which a time-compressed PCM audio signal is recorded by increasing the overlap portion.

FIG. 16 shows each magnetic head 3, 4, 5.6 (FIG. 3 (to)) in such an overlapped PCM voice encoding recording method.
2 is a timing chart showing signals supplied to the
D is a time-compressed PCM audio signal, and signals corresponding to those in FIG. 4 are given the same symbols.

When the signal to be recorded is a color television signal, signals A, B, and C are the L of the color television signal.
These are component signals such as L, G, B signals, Y signal, RY signal, B-Y signal, etc. (see Figure 3), when the magnetic tape 1 hits the YIC head cylinder 2 in the rotational direction well beyond point E. A contiguous section is provided, and the time compressed P is set in that section.
A D signal, which is a CM audio signal, is recorded.

For this purpose, as shown in FIG.
4, 5.6, signals A, B, of one field period T,
After C is supplied (of course, an overlap period δ is also included, but the explanation is omitted), a signal is further supplied for a period T corresponding to the section from the above point E. As a result, as shown in FIG. 17, for each recording trunk CH, CH6, CH, .
, B, and C. The D signal is recorded on an extension of the recording areas of , B, and C. In this case, the D signal is recorded for each recording track, so
Each field is recorded three times, and thus an audio signal corresponding to 1/3 field period is recorded on each recording track. For example, if an audio signal is time-compressed to 1/6, the audio signal recorded on one recording track will be 1/6 x 1/3 = 1/1
This corresponds to 8 field periods, and the angle of winding the magnetic tape 1 around the head cylinder 2 (FIG. 3) to record this is 360° x 1/18 x 3/4 = 15°. Become. That is, the increase in tape wrapping angle is, in this case,
It is approximately 15°, and there is no need to increase the tape wrapping angle as much. Of course, when after-recording is not performed and the luminance signal and color difference signal are recorded, the time-compressed PCM audio signal is placed in the vertical blanking period of the color difference signal, and the overlap wrap angle is adjusted. You can also choose not to increase it.

In addition, in FIG. 17, signals A,
A guard section G is provided between the B and C recording areas and the signal recording area to separate these signals and prevent interference.

Next, another specific example of the signals supplied to each magnetic head in this embodiment will be described.

Figure 18 is a timing chart showing signal conversion during recording, where S is the signal to be recorded and A, B, and C are the signals A, B, C, H, , H, respectively, in Figure 4.

(3, . . . are IH signals.

In FIG. 18, the recording target signal S is referred to as a video signal)
From this, IH video signals are extracted every 3H,
Furthermore, the time axis of the IH video signal is expanded three times to 3H.
IH video signal whose time axis has been expanded (hereinafter referred to as time axis expanded IH video signal) Hl*H4+i-i,
A signal A consisting of t... is formed.

In the same way, other IH video signals every 2H are extracted from the video signal S, and from this, time axis expansion 11'' video signals n; , n; , [(; , . . .
From the remaining IH video signals every 214 in the video signal S, time axis expansion I
A 4S No. C consisting of an H video signal is formed. These signals A, B, and C are recorded as shown in Figure 5.

As the time axis expansion means, a memory equivalent to IH is used, and by setting the reading speed to 1/3 of the writing speed, it is possible to expand the time 1ssI nAn by three times. For example, to explain the formation of signal A, two memories corresponding to 111 are provided, and one memory has 114 videos each issue 1-1. and write this at 1/3 of the writing speed
The video signal H+k is read out at a readout speed of 3HK to obtain a time-axis expanded II-1 video signal H+k. This 11
1 When 2 I-1 has elapsed after the start of reading of video signal H1, loading of IH video signal H4 to the other memory is started, and reading of IH video signal H, is completed, and at the same time, reading of IH video signal H, convolution speed 1
The time axis expanded IH video signal H4' which is started at a readout speed of /3 and expanded to 3H is obtained.

In this way, the two memories are operated alternately and the write mode and output mode are different between the two memories.
11-1 video signal n, , H4,H, every H.

The oath of... is read out. signal B,
The same applies to the case of forming C.

Note that analog memory may be used as the memory equivalent to IH, but digital memory may also be used. In this case, the IH video signal is converted to a digital signal by an analog/digital converter, and this is converted into a digital signal. It is sufficient to expand the time axis using a digital memory as described above, and then convert it into an analog signal using a digital/analog converter.

FIG. 19 is a timing chart showing the process of converting the signals A, H, and C in FIG. 18 into the original signal S (g process, and the signals corresponding to those in FIG. 18 are given the same reference numerals.

Signals A, B, and C in FIG. 18 are recorded one field at a time in each recording track, respectively, as shown in FIG. 5. During reproduction, signals A, B, and C are generated from each recording track. As explained above, B and C are each turned into continuous signals by the switching means.

Therefore, in FIG. 19, each signal A, B, C is a time-axis expanded IH video signal HI H'H2#...
The time axis is compressed to 1/3 sequentially, and the IH video signal H1
゜H,,H,,... howl. As a result, signal A
, B, and C are shifted in phase by IH and become intermittent signals every 2H, and by combining these, the original video signal S is obtained.

As the time axis compression means, a 3H phase memory is used, and by setting the reading speed to three times the writing speed, a 3H time axis expanded IH video signal can be converted into an IH video signal. For example, to explain the time axis compression of signal A, use two 3H equivalent notes IJ'& 18th
Similarly to the case of time axis expansion in the figure, one and two memories are written in alternately, and the two memories are written in different read modes to expand the time axis of signal A.IH video signal H
1'z Toi:l H? Time axis compression is performed every #. The same applies to signals B and C.

Note that by using the recording tracks formed as shown in Figure 5, the three signals reproduced from each magnetic head can be compressed directly in time without converting them into continuous signals A, B, and C. In this case, the original video signal S is restored by combining the three time-axis compressed signals.

In such a specific example, the signals A and B recorded by the magnetic head
, C are three-channel signals obtained by expanding the time axis of the original video signal S by three times, so the frequency band of the signal recorded per channel is 1/1 of that of the original video signal S.
3, and can record video signals with three times the frequency band compared to conventional one-channel recording systems.

From this, it is possible to realize a magnetic recording and reproducing device that is compact and capable of recording and reproducing broadband analog signals. Furthermore, the present invention is particularly effective when converting an analog signal into a digital signal for recording and reproduction, since the digital signal requires a wider frequency band than the analog signal (Th signal).

Next, the above specific example will be explained assuming that the signal to be recorded is a color television signal.

FIG. 4(f) is a block diagram showing a specific example of a recording circuit for this purpose, and 70, 71, and 72 are input terminals.

73, 74.75 is a time axis compression circuit, 76 is a synthesis circuit,
77 is a switch circuit, 18, 79, and 80 are time axis expansion circuits, and parts corresponding to those in FIG. 6(A) are given the same reference numerals, and some explanations will be omitted.

In Fig. 4 (A), input terminals 70, 71, and 72 respectively supply a Y signal, an R-¥ signal, and a B-Y signal.
The time axis is compressed for each IH by time axis compression circuits 73, 74, and 75. Time axis compressed Y signal, RY signal.

The B-Y signals are temporally shifted from each other, and the synthesis circuit 76
A time-division multiple signal, that is, a time-plex signal, is obtained. In this case, the time axis compression circuit 73.
74L Y signal, RY signal from 75.

The B-Y signals are compressed on the time axis so that their frequency bands are almost equal to each other. For example, as shown in FIG. 21, for each IH, the R-Y signal, the B-Y signal, and the Y signal are Arranged chronologically. This time-plex signal is the video signal S shown in FIG.

This timeplex signal is supplied to a switch circuit 77, and distributed and supplied to time axis expansion circuits 78, 79, and 80 sequentially for each IH. Therefore, from the time axis expansion circuit 78, the first
A signal corresponding to signal A in Figure 8 is obtained, and in the same way, the time axis compression circuit '/! -) and 80, signals corresponding to signals B and C in FIG. 18 are obtained.

The subsequent processing is similar to that of the recording circuit shown in FIG. 6 (5), and as shown in FIG. 4, each magnetic head 3.4.
．． 5.6 is supplied with a signal.

FIG. 4(B) is a block diagram showing a specific example of a reproducing circuit, in which 81.82.83.84 is a demodulator, 85.8
6゜87.88 is a time axis compression circuit, 89 is a synthesis circuit, 9
0 is the separation circuit, 91.92.93 is the time axis expansion circuit,
94.95°96 is an output terminal, and the portion corresponding to the 6th @ (b) is given the same reference numeral.

In FIG. 4 (I3), the reproduction signals of the magnetic heads 3, 4, and 5.6 are amplified by reproduction amplifiers 29, 30, 31, and 32, respectively, and demodulated by demodulators 81, 82, 83, and 84, and the time axis The compression circuit 85.86.87.88 is supplied. The time axis compression circuit 85 generates a timeplex signal A consisting of a time axis expanded IH video signal as shown in FIG.

A signal in which B and C are arranged at intervals of 1/3 field period for each field period (see Figure 4) is called 3H.
The time axis is compressed to 1/3 for each period and arranged every 2H.
An intermittent signal consisting of 14 video signals is formed. Similarly, time axis compression circuits 86, 87, and 88 form interval signals consisting of IH video signals arranged every 2H. That is, during recording, as shown in FIG.
5.6 signal S,.

Since S4h "'I+ +"'6 is recorded, the magnetic head 3. 4. The signal reproduced in 5.6 is also represented in FIG. Therefore, the reproduction signal is supplied to three of the time axis compression circuits 85, 86, 87, and 88, and the reproduction signal is supplied from one of these three for every 1/3 field. is switched to the remaining one that was not supplied. Then, one of the above three compresses the time axis of signal A,
One of the other two compresses the signal Bi on the time axis, and the other compresses the signal C on the time axis. In short, the combining circuit 89 is always supplied with intermittent signals A, B, and C made up of IH video signals that are time-base compressed for each time-base expanded IH video signal and arranged every 2H.

As is clear from Fig. 19, the reproduced signals A, B, and C are sequentially shifted in time by the IH punishment period, and furthermore,
This is because the information content is delayed by IH in the order of signals A, E, and C (that is, for example, the 19th
In the figure, HJ is IH behind H8' and I-
1,'), the signals A and B are eventually supplied to the combining circuit 89.
, C are in an interpolation relationship with each other on the time axis. Therefore, these signals A.

By combining B and C-i, a time-plex signal (FIG. 21), which is the same as the time-plex signal obtained by the combining circuit 76 of FIG. 4(A), is obtained.

This time-plex signal is supplied to a separation circuit 90, and the time-axis compressed Y signal, l(, -Y signal).

It is separated into B and Y signals. These Y signals, R-Y signals,
The B-Y signal is supplied to time axis expansion circuits 91 and 92° 93, respectively, where the time axis is expanded, and output terminals 94.95° 96 output the Y signal, R'-Y signal, and B- signal on the original time axis, respectively. A Y signal is obtained.

Note that when the time axis compression circuits 85, 86, 87, and 88 compress the time axis of each reproduced signal, the time axis compression circuit 85
, 86, 8'7, and 88 are written to the memory using a clock signal synchronized with the reproduction signal, and reading is performed using a clock signal that has a frequency three times that of the writing clock signal and has no time axis fluctuation. By doing so, it is possible to correct the time-axis fluctuations of the reproduced signal, and it is possible to obtain a reproduced image without time-curved axis fluctuations.

Next, a case will be described in which an analog signal is recorded as a digital signal in this embodiment.

FIG. 22(A) shows a recording circuit for this purpose, and FIG. 22(C) is a block diagram showing a reproducing circuit, where 97°98.99 is an input terminal, 100. 101. 102 is an analog/digital converter, 103. 104. 10
5 is memory.

106 is a clock generation circuit; 107. 108. 10
9 is a synthesis circuit, 110. 111. 112 is an error check bit addition circuit; 113. 114. 115.
116 is a modulation circuit.

117, 118. 119. 120 is a demodulator, 121
．． 122゜123, 124 is an error correction circuit, 12
5. 126. 127°1' 128 is a time axis compression circuit, 129 is a synthesis circuit, 130 is a separation circuit, 131. 1
32. 133 is a time axis expansion circuit.

134, 135. 136 is a digital/analog converter.

137, 138. 139 is an output terminal, as shown in FIG. 6 (5).

Parts corresponding to (8) are given the same reference numerals.

First, the recording circuit shown in FIG. 22(A) will be explained.

Y signal supplied from input terminal 97.98.99, R-
The Y signal and the B-Y signal are each output from an analog/digital converter (hereinafter referred to as an A/D converter) ioo.

101; 102, respectively, for example, into an 8-pit digital signal, and the IH annual memo I7103. 1
04°105. A/D converter 100. 1
As the sampling clock No. 6 of 01°102,
A clock signal synchronized with a horizontal synchronization signal included in the Y signal from input terminal 97 is used, and this clock signal is generated by a clock generation circuit 106 which receives this horizontal synchronization signal as input.

Memory 103. 104. 105 and a synthesis circuit 107.
108°109 is the digitized Y signal, )L
-Y signal.

The B=y signal (hereinafter referred to as digital/L/Y signal, digital (R-Y) signal, and digital (B-Y) signal, respectively) was formed into a timeplex signal, and the time axis was expanded three times. 3. Formation of glaze signals.

Taking a 4:2:2 component format digital VTR as an example, the time prep signal to be formed is arranged in a digitized 160-bit format as shown in Figure 23. Starting with synchronization signal H8,
Assuming 1 sample is 8 bits, 720 samples of digital/l/Y signal, 36o samples of digital (几-Y)<
Th number and 360 sample digital (BY) signal.

Therefore, a memory 103 for expanding the time axis of the time-plex signal three times and forming three types of signals. 1
04. 105 and a synthesis circuit 107. 108. 109
The operation of ゜ will be explained using FIG. 24. In addition, the 24th
In the figure, corresponding signals in FIG. 22 (6) are given the same reference numerals.

The memories 103, 104, and 105 each have three memory devices equivalent to IH. To explain the memory 103, the supplied digital Y signal Y, ll
are sequentially distributed and written into these three memory devices 6 by IH. The digital Y signals written to each memory device are indicated by Y, , Y, , Yo in the diagram. Each memory device reads at about 2/3 of the write speed, so each memory device reads every 11-1 digital Y
The time axis of signal YD is expanded to 3/21-1.

Therefore, from the memory 103, every 21-1 IH
Intermittent digital Y signal Y, , Y, , '
3-glaze signal Y in which Yc has been expanded in time by approximately 3/2 times;
Y; , Y; are obtained. These signals y, l,
Y; , Y≦ are sequentially shifted in time by IH, and the signal Y1 is supplied to the synthesis circuit 107, the signal Yz to the synthesis circuit 108, and the signal YJ to the synthesis circuit 109, respectively.

Similarly, in the memory 104, the digital (1 and -Y) signal (RY)D is sequentially distributed to three memory devices II-i and stored. The signals written to each memory device are shown in Figure z1 ()! , -Y),.

(R-y)ll, (R-\)c. Each memory device reads at about 4/3 the write speed, thus (RY)A, (RY),.

(RY), a signal in which the time axis of each IH signal is compressed to about 3/4 (l(,-y); , (R-y)≦,
(a-y),' are obtained. Note that (RY), the read timing of the memory device in which the signal is written is memory 1.
After the memory device that reads the signal Y in 03 finishes reading the IH signal sound, it is set to start reading immediately. Similarly, the signals (1 also -Y), , (R
-Y) The read timing of the memory device for convolving the signals Y and Yc in the memory 103, respectively, is such that the memory device that writes all the signals starts reading out the foi immediately after the memory device has finished reading the IH signal. Set.

Also in the memory 105, the digital (B-Y) signal (B
-Y) IH is sequentially distributed and stored into three memory devices. The signals stored in each memory device are shown in Figure 24 as (B-Y)A, (B-Y)l, (B-Y)
Y) Shown as c. Each memory device reads at a speed of approximately 473 times the write speed, <B-y,),
CB-Y)+t, (B-Y,)c Signal valley IH
A signal whose time axis is compressed to about 3/4 (B-y)
:, (B-Y);, (B-y);

(H-Y), , (B-Y)B, (B Y)c are stored in the memory device ``h5 output timing, respectively (1 is also -Y), , (ratio- y)m, (R-
Y) After the memory device that writes c to M' finishes reading out the IH signal, it is set to start reading at 111.

Next, note +) 103. 104. 105 Karano Y
; The signal (and -Y)A signal and the (BY)A signal are synthesized by a synthesis circuit 107. As a result, from the synthesis circuit 107, the 11-1 period is about 3/2 the I-1 period, and the I-1 period is time-axis expanded, and the IH period is about 3/4H period/time-axis compressed, respectively. A time-plex signal λ is obtained in which the RY) signal and the digital (13-Y) signal are arranged in time series.

Similarly, in the synthesis circuit 108, the ¥8' signal, (R-Y
), 'signal and (A3-Y)B'id signal are combined to generate time-plex signal B', and in the synthesis circuit 109, Yc' signal, (R-Y)e' times signal and ( 1
3-Y) are synthesized to form a time-plex signal C'
is obtained.

These time-plex signals A', B', C' are approximately (3
/2H+3/4)1 +3/4H) :=A signal with a period of about 3H, and at a ratio of 4:222 for each period, digital Y signal, digital) L/(R-Y) signal, digital ( B-
Y) The signals are arranged in a time-series manner, and the time-plex signal 'f' shown in FIG.

IH including information contents shifted by IH in the order of B' and C'
These are signals that are shifted in time. Therefore, the time-plex signals r, H', c/ are shown in FIG. 18, respectively.

This corresponds to signals A, B, and C in FIG.

These timeplex signals A', B', and C' are
Error check pit addition circuit 110. Error check bits are added at 111° and 112. Figure 5 shows a specific example of error check bit addition, in which 12 samples of a time-plex signal are taken as one block, and check pits are added using a Galois field (GF'(28)) (16, 12) lead dot Romon code. This is an example of the data arrangement when S is an 8-bit synchronization bit, and A
D is 8-bit address bit), ST is 12 samples 8
Bit data bit.

PC is a 32-bit parity bit, and ER is a 16-bit error detection code.

Signals A and B' with error check bits added.

C' is divided into four channels by the distribution circuit 19 as already mentioned, and each channel is divided into four channels by the modulation circuits 113, 114,
115, a predetermined modulation is applied to each magnetic head 3, 4.
, 5.6 as described above.

Next, the reproduction circuit shown in FIG. 22 σ3) will be explained.

Reproduction signals from the magnetic heads 3, 4, 5, and 6 are amplified by reproduction amplifiers 29, 30, 31, and 32, respectively, and then sent to a demodulator 11.
7. 118. 119. At 120, the signal is demodulated to the original digital signal. Each demodulated digital signal is sent to an error correction circuit 121. 122. 123. At step 124, the errors are corrected, respectively, and the time-plex signals A', B', and C' having a period of 3H in the diagram are obtained. These time-plex signals A', B', and C' are compressed to 1/3 in time by the time-base compression circuits 125, 126, and 127, and are also compressed by the time-base compression circuit 85 in the diagram (13).
．． Similarly to 86.87.88, the time axis fluctuations are corrected and synthesized in the synthesis circuit 129 to obtain the IHi period, and as shown in FIG. Digital (l(, -Y') signal, digital (B-Y)
A timeplex signal is obtained in which the newspapers are arranged in chronological order. This timeplex signal is minute 1ijli
The circuit 130 generates a digital Y signal, digital (R-Y) (f
i issue.

Separated into digital (B-Y) signals.

The digital Y signal is supplied to the time axis expansion circuit 131 and
Similarly, the digital (RY) signal and the digital (B-Y) signal are expanded by the time axis expansion circuit 132.
133, the time axis is expanded by four times, and time alignment is performed with the digital Y signal whose time axis length is lengthened. 135.
136, it is converted into an analog signal. As a result, the original Y signal is sent to the output terminal 137, and the original R-Y signal is sent to the output terminal 138.
The original H-Y signal is also available at output terminal 139.

This specific example is an example of channel division of a digital signal, and unlike analog signals, digital signals can be easily divided into channels, and other channel divisions are also possible. Furthermore, in this specific example, memory 103. 104. The A/D converter 100.105 simultaneously performs time axis expansion, compression, and channel division. Digital Y signal from 101°102,
First, a time-plex signal is formed using the digital (RY) signal and the digital (B-Y) signal, and from this time-plex signal, channel division and time axis expansion are performed to obtain the signals h' and B shown in FIG. ', C' can also be formed.

Furthermore, in addition to the video signal, digital audio signals or digital data can also be recorded simultaneously with the video signal. - For example, by slightly reducing the entire video signal area of the time-plex signal shown in Figure 81423 and inserting digital audio signals and digital data signals into the resulting margins, it becomes possible to record and reproduce these signals.

FIG. 26 is a plan view showing the head cylinder section of another embodiment of the magnetic recording/reproducing device by Kinoe I.
Parts corresponding to A) are given the same reference numerals.

In Figure n, the outer periphery of the head cylinder 2 has 120
Magnetic heads 3 having mutually different azimuth angles at equal intervals of °,
4.5 are provided, and the magnetic tape 1 is guided by a tape guide 7.
8, it is wound around the head cylinder 2 in a strong 240° spiral. Therefore, three magnetic heads 3
, 4.5, two magnetic heads rotate in the Y direction over a 240° section from point S to point E and scan the magnetic tape, but the remaining magnetic head scans the magnetic tape from point E to point S
There is a section VC up to VC, which is separated from the magnetic tape 1 except for the overlapped portion. The head cylinder 2 rotates 240° in 1 field, and therefore rotates 240° in 1 field.
/3 rotations, rotation period TI! is a 3/2 field. In other words, when the field frequency of the head cylinder 2 is 60 Hz, the speed of the head cylinder 2 is 60 x 2/3 = 40 rps.
Rotate with.

In this embodiment, the recording signals are two types of signals A and H.
(which is shown in the figure), at time t0,
When the magnetic head 5 to which the signal B was supplied crosses the point 1 bow, if the recording of the overlapped portion is ignored, the signal 13
The supply force is switched from the magnetic head 5 to the magnetic head 3, which reaches the point S 120 degrees ahead of the magnetic head 5. At this time, the signal A is being supplied to the magnetic head 4.

Then, the magnetic head 3 starts recording the signal B, and the magnetic head 4 continues recording the signal A. The head is switched to head 5.

In this way, each magnetic head 3, 4.5 records a signal one field per 240° rotation interval from point S to point E, and when it reaches point E, it reaches point S 1000 times earlier. Switch the signal supply to the magnetic head that is connected.

Therefore, as shown in FIG.
．． The signals S3,' S4. S is one field T for every rotation period of the head cylinder 2.
.

No. 6 A and B are supplied alternately for each period, and the signal A
, B supply timing is signal 8M + S4 y
As a result, as shown in FIG. 28, the recording trunk where the signal A is recorded and the recording track where the signal B is recorded are arranged in the order of are formed alternately.In this case, the magnetic heads 3,
4.5 has different azimuth angles, so V! The directions of the four-contact tracks are different, and crosstalk from adjacent trunks can be eliminated during playback. Furthermore, if the width of the recording trunk of the magnetic tape 1 is P/2, and P is the pitch, then the track width of the magnetic heads 3 and 4.5 is slightly thicker than P/2 (formed by the preceding magnetic head). Next, Me

In this embodiment, when the signal to be recorded is a color television signal, the signal A is the frequency-modulated luminance signal FM (g) shown in FIG. It can be a time-plex color difference signal of trowel). However, this is not the only signal, and other signals may be used. In addition, the audio signal is also shown in Figure 13 (5).
However, it is clear that frequency division multiplexing with the video signal may be used as shown in (), or an overlap recording method may be used as shown in FIGS. 16 and 17.

The cases where the number of magnetic heads is 4 and 3 have been described above, but as is clear from the above description, it is generally possible to have n magnetic heads of 3 or more.
In this case, by arranging n magnetic heads at equal intervals around the outer circumference of the head cylinder and setting the winding angle of the magnetic tape around the head cylinder to the above value, it is possible to
It becomes possible to record No. 1.

Further, so far, the case has been described in which the magnetic head has an azimuth angle, but if a guard band is provided between adjacent tracks, it is also possible to make the magnetic head not have an azimuth angle.

Furthermore, although the case where one field's worth of signals is recorded on one recording track has been described, the present invention is not limited to this, for example, one field's worth of information is recorded on one recording trunk.
/lc (where k is a natural number) may be recorded, and in this case, the number of rotations of the head cylinder will be doubled.

Furthermore, in the above embodiments, the recording and reproduction of television signals has been mainly explained, but the present invention 1.
It is clear that other information signals may also be used. It is also clear that the multiple product signals recorded may be independent signals that are not related to each other.

Furthermore, it is obvious that all conventional methods are applicable to the present invention, including the running direction of the magnetic tape and the scanning direction of the magnetic head, including the directions shown in the above embodiments.

〔Effect of the invention〕

According to the above-described VC, according to the present invention, a different number is supplied to each magnetic head during the period when the number of magnetic heads provided in the head cylinder is in contact with the magnetic tape. It is possible to expand the frequency band of recording No. 48 to the recordable band of each band, which makes it possible to record and reproduce wideband signals.Moreover, it is possible to prevent the diameter of the head cylinder from increasing, making it possible to improve the performance of the device. small, V
It is possible to reduce i quantity, cost, etc.,
It is possible to provide a magnetic recording/reproducing device with excellent functionality by eliminating the drawbacks of the prior art described above.

[Brief explanation of drawings]

FIG. 1 is a plan view showing a head cylinder section of a conventional magnetic recording/reproducing device 9, FIG. 2 is a schematic diagram showing a recording trunk pattern on a magnetic tape formed by the head cylinder section of FIG. 1, and FIG. 5), however, Fig. 5 shows one embodiment of the magnetic recording/reproducing device according to the present invention, and
Figures (G) and υ) are a plan view and side view showing the head cylinder section, Figure 4 is a timing chart of the signals supplied to each magnetic head in Figure 3 (G), and Figure 5 is a diagram showing the head cylinder section. A schematic diagram showing the recording track pattern formed on the tape [Sl, i6 (c)], @ is a block diagram showing a specific example of the recording circuit and the reproducing circuit, and Fig. 7 shows the distribution of Fig. 6 (5). Signal waveform diagram showing input signals of the circuit, Ki 8 (8), Q3
) is a block diagram showing another specific example of a recording circuit and a reproducing circuit, FIG. 9 (5), however), 0 is a frequency spectrum diagram showing a specific example of a recording signal in FIG. Fig. 10 (g), σ3), 0 is a frequency spectrum diagram showing another specific example of the recording signal of Fig. 8 (A), ' (f3), Fig. 11
The figure is a schematic diagram showing another recording track pattern formed on a magnetic tape. Fig. 12 is a timing chart of signals supplied to each magnetic head for this purpose, Figs. 13 (A) and (B) are frequency spectrum diagrams showing a specific example of a recording signal for this purpose, and Fig. 14 is a timing chart of signals supplied to each magnetic head for this purpose. Figure 13 (B) is a signal waveform diagram showing a recording signal having the frequency spectrum, Figure 15 is a schematic diagram showing a recording pattern of a tracking pilot signal, and Figure 16 is a signal waveform diagram showing a recording pattern of a tracking pilot signal. 17 is a schematic diagram showing the recording track pattern, FIG. 18 is a timing chart showing signal conversion during recording, and FIG. 19 is a timing chart of the supplied signal.
The figure is a timing chart showing signal conversion during playback, Figure 1 (G). ()3) is a block diagram showing a recording circuit and a reproducing circuit for recording and reproducing a color video signal as a timeplex signal, FIG. 21 is a schematic diagram showing an example of a timeplex signal, and FIG. (B) is a block diagram showing a recording circuit and a reproducing circuit for recording and reproducing a color video signal as an all-digital timeplex signal, FIG. n is a schematic diagram showing an example of a digital timeplex signal, and FIG. FIG. 5 is a schematic diagram showing one block of a digital time-plex signal to which an error check bit has been added; FIGS. Figure A shows another embodiment of the magnetic recording and reproducing device according to the present invention,
The second figure is a plan view showing the head cylinder section. FIG. 27 is a timing chart of signals supplied to each magnetic head in FIG. 26, and FIG. 27 is a schematic diagram showing a recording track pattern formed on the magnetic tape. 1...magnetic tape, 2. song/head cylinder,
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Claims (1)

[Claims] In a helical scan type magnetic recording/reproducing device, n magnetic heads (where n is a positive integer of 3 or more) are arranged at approximately equal intervals in the circumferential direction of a head cylinder, and a magnetic tape is spread around the outer circumference of the head cylinder. at least 360°
The winding is made to run spirally over an angular range of -1/n), m (however, m is an integer of 2 or more, and m≦n).
Separate recording signals are supplied to different magnetic heads running the magnetic tape for at least (n-1/n) rotation periods to record the magnetic tape, and the magnetic heads for recording each of the recording signals are supplied for at least (n-1/n) rotation periods. 1/n) A magnetic recording/reproducing device characterized in that it is configured to sequentially switch each rotation.