JPS6185603A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To record various information signals on areas divided in the breadthwise direction by recording and reproducing individual information signals with rotary head groups different from one another and providing a step in the direction of a revolving shaft between rotary head groups and setting the winding angle of a magnetic tape around a rotary drum to 180 deg.. CONSTITUTION:A pair of rotary heads 25 and 26 are provided at an angular interval of 180 deg. on the outside peripheral surface of a rotary drum 2 and at the same height in the direction of the revolving shaft and are different in azimuth angle from each other. A pair of rotary heads 27 and 28 are provided at an angular interval of 180 deg. on the outside peripheral surface of the drum 2 and at the same height in the direction of the revolving shaft and are different in azimuth angle from each other. The plane of rotation of heads 25 and 26 is different from that heads 27 and 28 in the direction of the revolving shaft by a height (d). A magnetic tape 1 is wound at about 180 deg. around the drum 2 by guide posts 4 and 5. Thus, a video signal and a time base compressed PCM sound signal are recorded and reproduced on a section RT having a width WV of the tape 1 and a section RA having a width WA' respectively.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention is a method for separately dividing different information signals such as video signals and PCM audio signals into different areas divided in the width direction on a magnetic tape. The present invention relates to a Vericals-Yang type magnetic recording and reproducing device for recording.

[Background of the invention]

In recent years, helical scan type magnetic recording and reproducing devices (hereinafter referred to as
In the field of VTR (abbreviated as VTR), there is a trend toward increasingly higher density recording. One way to increase the recording density is to slow down the running speed of the magnetic tape.The adoption of this method results in a relative increase in fluctuations in the running speed of the magnetic tape, and also reduces the recording frequency. Bandwidth is becoming narrower and narrower. As a result, it has become extremely difficult to obtain reproduced audio of good quality using conventional audio signal recording and reproducing systems using fixed heads.

Therefore, in order to solve this problem, the magnetic tape is wound more than 180 degrees around a rotating drum equipped with a one-rotation head. Record the signal and also record the continuous audio signal over a unit time (e.g.
The PCM audio signal is divided into periods (corresponding to the field period of the video signal), time axis compressed, and PCM modulated to obtain an intermittent time axis compressed PCM audio signal, which is recorded on a magnetic tape with 18
The rotation head is used to record excess winding beyond 0° (hereinafter referred to as an overlap section), and video signals and audio signals are recorded separately in different areas divided in the width direction of the magnetic tape. A so-called audio signal overlap recording method has been proposed.

FIG. 1 is a perspective view showing the cylinder part of the VTR,
l is a magnetic tape, 2 is a rotating drum, 3 is a fixed drum, 4
．． 5 is a guide post.

In the same figure, the magnetic tape l has a guide post voltage of 4.5V.
From C, the rotary drum 2Vc is wound spirally and travels in the direction of arrow a. Rotating drum 2.

It rotates in the direction of the arrow at a rotation frequency equal to the frame frequency (rs, for example, 30 Hz) of the video signal.

In the audio signal overlap recording method, as shown in FIG. 2, which is a plan view of FIG.
@100 wrapped around it.

On the outer periphery of the rotating drum 2, two rotating heads 6.7 having different azimuth angles are arranged at an angular interval of 180° and with the same gap height, that is, the same rotating surface)rc
It is installed as it is.

As is clear from FIG. 1, these rotating heads 6.7 scan the running magnetic tape l obliquely from the lower edge to the upper edge.
During the winding of 180' + θ, one of the rotating heads 6 and 7 scans the magnetic tape l, and for the remaining θ, the rotating head 6. 6.7 are simultaneously scanning the magnetic tape l.

The scanning of the magnetic tape by the rotary head 6.7 will be explained in more detail with reference to FIG. 2. The rotary drum 2 rotates in the direction indicated by the arrow,
) has started scanning the magnetic tape 1 and is scanning the winding portion of θ, the other rotating head is still scanning the magnetic tape l, and the one rotating head is scanning the magnetic tape l. When the winding .theta. finishes scanning the magnetic tape l, the other rotary head finishes scanning the magnetic tape l.

This θ winding of the magnetic tape l is an overlap section in which the time axis is compressed and a PCM audio signal (hereinafter referred to as a time axis compressed PCM audio signal) is recorded.゛Video signals can be recorded in minutes.

FIG. 3 is a pattern diagram showing tracks on a magnetic tape l formed by such an audio signal overlap recording method, and 8 is a track.

The rotating heads 6.7 (Fig. 2) each start scanning from a position separated by a predetermined distance y0 from the lower end of the magnetic tape l, and the winding of the magnetic tape l corresponds to an angle θ (Fig. 2). After scanning the section RA of the width WA, the winding of the magnetic tape l scans the section Rv of @Wv corresponding to the corner 180'. The magnetic heads 6.7 alternately scan the magnetic tape 1, forming tracks 8 at a predetermined track pitch during recording, and reproducing and scanning tracks 8 at a predetermined track pitch during reproduction. Note that β is the inclination angle of the track 8 with respect to the longitudinal direction of the magnetic tape l.

Figure Wc4 is a block diagram showing an example of a conventional recording/reproducing system, where 9.10 is an input terminal, 11.12 is a switch, and 13 is an input terminal.
．． 14 is a recording amplifier, 15.16 is a switch, 17.18
is a rotary transformer, 19°20 is a preamplifier, 21
．． 22 is a switching device, 23° and 24 are output terminals, 25 is an input terminal, and 6.7 is a rotating head shown in the gz diagram.

In FIG. 4, the switching devices 11, 12, 21, 22 are controlled by the head switching pulse 5WVc from the input terminal 25, and the rotating head 6.7 is wound at an angle σ (FIG. 2).
Every time you finish scanning the overramp section, contact points a to b
Again, switch from contact to a. Switch 15.16
The contact P@tc is closed during recording, and the contact P@tc is closed during playback.

Next, the operation of this recording/reproducing system will be explained using the timing charts of FIGS. 2, 3, and 5.

First, during recording, time axis compression P is input from input terminal 9.
A CM audio signal A is supplied, and a video signal (hereinafter simply referred to as a video signal) (2) that has undergone predetermined processing such as FM modulation is supplied from the input terminal IO. In a time-axis compressed PCM audio signal, a continuous audio signal is divided into one field period of a video signal as a unit of time, and the audio signal for each unit time is PCM-modulated at a predetermined ratio θ/180°. It is an intermittent signal that has been covered by a shaft.

Now, as shown in FIG. 2, it is assumed that the rotating head 7 scans the magnetic tape 10 around the rotating drum 2 by 180 degrees, and that the rotating head 6 is away from the magnetic tape.
The head switching pulse SW is 'L', and the switching device 11.1
2, the contact a side (opposite side as shown) Ic is closed. At this time, the time-base compressed PCM audio signal A is not supplied from the input terminal 9, and the video signal ■ from the input terminal 1O is passed through the switch 12, the recording amplifier 14, the switch 16, and the rotary transformer 18, and the recording signal It is supplied to the rad 7 for rotation as S8. Therefore, the VC video signal is recorded in section Rv (FIG. 3) of the magnetic tape 1.

When the rotary drum 2 rotates and the rotary head 6 starts scanning the magnetic tape 1, the time-base compressed PCM audio signal A is transmitted from the input terminal 9 to the switching device 11, the recording amplifier 13. Switch 15
, the recording signal S1 is supplied to the rotary head 6 via the rotary transformer 17. This time-base compressed PCM audio signal is supplied to the rotating head 6 while the rotating head 6 scans the overlap section of the magnetic tape L at an angle θ, and during this time, the rotating head 7 is supplied with the video signal . is supplied as the recording signal S2.

As a result, on the magnetic tag l, the time axis compression P
CM audio signal person should be recorded.

When the rotating head 6 finishes scanning the overlap section of the magnetic tape l at an angle θ, the head switching pulse SW changes to l.
IH'', the switch 11, 12 switches to contact b@, and becomes the state shown in the figure.Therefore, the time-base compressed PCM audio No. G A is no longer supplied from the input terminal 9, and the video signal V
The recording signal S,
A rotary head 6tC is supplied to the magnetic tape 1, and a time-base compressed PCM audio signal is recorded on the magnetic tape 1 in a section Rv following the time axis compressed PCM audio signal.

Thereafter, this operation is repeated every rotation of the rotary drum 2, and the section RA of each track of the magnetic tape 1 shown in FIG.
Time base compressed PCM with VC1 field period information
A signal person is recorded, and a video signal V of section Rv[1 field is recorded.

Next, at the time of playback +c, the switch 15.16 is connected to the contact P.
@VC can be switched.

Now, the rotating head 7 is wrapping the magnetic tape l at an angle of 180 degrees.
When scanning the section Rv of the part of °, and assuming that the rotary head 6 is away from the magnetic tape l, the head switching pulse SW is "L", and the switches 21 and 22 are closed to the contacts a@, as shown in the figure. is in the opposite situation.

Therefore, the reproduced signal S2 from the rotary head 7 is supplied to the output terminal 24 via the rotary transformer 18, the switch 16, and the preamplifier zO1 switch 22.
A 4tC video signal ■ is obtained.

When the rotary drum 2 rotates and the rotary head 6 starts scanning the winding of the magnetic tape 1 over the corner 00 overlap section, that is, the section RA in FIG. 3, the rotary head 6 reproduces the signal. This reproduction signal 81 is transmitted to the rotary transformer 17,
It is supplied to the output terminal 23 via the switching device 5, the preamplifier 19, and the switching device 21, and the time axis compression P is supplied to this output terminal 23.
A CM audio signal A is obtained.

When the rotating head 6 finishes scanning the over-ramp section with the winding angle θ, the rotating head 7 separates from the magnetic tape 1, and the head switching pulse SW becomes 'H' and the switching device 21
．． 22 switches to contact b@.

Therefore, the rotating head 6 wraps the magnetic tape l at an angle of 18 mm.
The 0° portion, that is, the section Rv shown in FIG. 3 is scanned. The reproduced signal S1 from the rotary head 6 is transmitted to the rotary transformer 17. The signal is supplied to an output terminal 24 via a switch 15, a preamplifier 19, and a switch 22, and a video signal V is obtained at this output terminal 24.

Thereafter, this operation is repeated every rotation of the rotary drum 201, and an intermittent time-base compressed PCM audio signal A is obtained at the output terminal 23, and a continuous video signal V is obtained at the output terminal 24.

Note that during recording, a signal for tracking control such as a magnetic tape IK control signal is recorded, and during playback, this signal is reproduced and the one-rotation head 6.7 accurately reproduces and scans the track corresponding to each azimuth angle. Needless to say, tracking control should be performed so as to

Further, the reproduced time-base compressed PCM audio signal A is then digitally time-base expanded and PeM demodulated to become a continuous audio signal. The reproduced video signal V is subjected to processing such as FM demodulation, but in the case of recording a color video signal, the VC is, for example, a luminance signal is FM modulated, a chroma signal is low frequency converted, and frequency multiplexed recording is performed. During playback, the luminance signal is FM demodulated, and the chroma signal is converted to its original frequency to form the original color video signal.

The above is the result of the conventional audio signal overlap recording method.
This is a recording/reproducing operation of a T-box, but in such a VT-box, a video signal and an audio signal are recorded and played back using the same rotating head, and a track for recording an audio signal is formed on an extension of a track for recording a video signal. Therefore, compared to a VTRK in which input of video signals is recorded using a rotating head, the winding angle of the magnetic tape around the rotating drum becomes larger. As a result, (1) the movement locus of the guide boss (4.5 for winding the magnetic tape around the rotating drum) (Fig. 2) becomes longer, and as a result, the necessary flat parts such as the chassis become wider. In addition, (2) the rotational load that the rotating drum receives from the magnetic tape and the running load that the magnetic tape receives from the fixed drum increase, resulting in adverse effects such as an increase in jitter and a deterioration in the quality of the reproduced image. It turns out.

[Purpose of the invention]

An object of the present invention is to eliminate the drawbacks of the above-mentioned prior art, reduce the angle of winding the magnetic tape around the rotating drum, and reduce the angle of the magnetic tape around the rotating head.
Accordingly, it is an object of the present invention to provide a magnetic recording/reproducing device which is capable of recording two different information signals in different areas divided in the width direction on a magnetic tape.

[Summary of the invention]

In order to achieve this object, the present invention performs VC so that each information signal is recorded and reproduced by different groups of rotary heads, and also provides a step between the groups of rotary heads in the direction of the rotation axis so that the respective rotation surfaces are The VC is characterized in that the positions at which the rotary heads start contacting the magnetic tape are shifted from each other in the width direction of the magnetic tape.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to FIGS. 6 to 9.

@Figure 6 (al, (bl) are a plan view and a side view showing one embodiment of the magnetic recording/reproducing device according to the present invention,
5 to 28 are rotary heads, and parts corresponding to those in FIG. 2 are given the same reference numerals.

In FIG. 6 Tag, fb) Ic, the rotating head 25.
26 are arranged in pairs on the outer periphery of the rotating drum 2 at an angular interval of 180' and at the same height in the direction of one rotational axis (not shown), that is, in the same rotational plane), and have different azimuth angles. There is. Further, the rotating heads 27 and 28 also form a pair, and are provided on the outer periphery of the rotating drum 2 at angular intervals of 180° and within the same rotational plane, and have mutually different azimuth angles. However, the rotating surfaces of the rotating heads 25 and 26 and the rotating surfaces of the rotating heads 27 and 28 are different from each other in the direction of the rotating axis.
A step is provided by CD. Here, the rotary heads 25 and 26 are provided higher than the rotary heads 27 and 28 by an amount d, and the former pair is used for recording and reproducing time-base compressed PCM audio signals, and the latter pair is used for recording and reproducing video signals. do.

Also, the line connecting the rotating head 25°26 and the rotating head 27
．． The line connecting 28 is set at a predetermined angle α. Furthermore, the magnetic tape l is wound around the rotating drum 2 by approximately 180° by the guide post 4.5.

FIG. 7 is a pattern diagram showing tracks formed on the magnetic tape L&C of FIG. 6(a), 25', 26
'.

27' and 28' are scanning trajectories of the rotary head, respectively.

In FIGS. 6(a) and 7, the inclination angle of the rotating drum 2 with respect to the longitudinal direction of the magnetic tape 1 is defined as β', and the rotating heads 27 and 28 are moved y from the lower end of the magnetic tape 1. When the contact is started from a position separated by 180° and the 180° winding section is scanned to move away from the magnetic tape l, the rotary head 25,26 moves from the lower end of the magnetic tape l to y0+W.
Starting contact at a distance A, the 180° wrap scans the section away from the magnetic tape l. here,
WA=acos β'. Further, the area where the rotary heads 25, 26 are in contact with the magnetic tape has a width Wv.

In addition, as described above, the rotary head 25 is higher than the rotary head 27, and the rotary head 26 is higher than the rotary head 28.
Since the rotary head 25 is placed ahead of K in the rotational direction (arrow b) by an angle α, when the rotary head 25 scans the magnetic tape, the rotary head 2 is placed ahead of the magnetic tape with a delay corresponding to the angle α.
7 starts scanning the magnetic tape. At this time, since the magnetic tape l is running, the rotating head 2 on the magnetic tape l
5 scanning locus 25', scanning locus 27' of rotating head 27
The inclination angle with respect to the longitudinal direction of the magnetic tape l is an angle! Differently, if this inclination angle is β and the traveling distance of the magnetic tape l per rotation of the rotating drum is V, then the scanning trajectory 25'
, 27' is the pinch p between.

The same applies to the rotary heads 26, 28, and the respective scanning trajectories 26', 28' also follow the scanning trajectories 25', 2'.
It has the same relationship as 7'. Note that the scanning trajectories 25', 26
It goes without saying that the pitch between ' and the scanning trajectories 27' and 28' is equal to T and is constant.

In this way, the rotary heads 25 to 28 scan the magnetic tape 1, and the rotary heads 25 and 26 are supplied with a video signal for the entire period of scanning the magnetic tape 1 (that is, the period Rv of width Wv). Therefore, the scanning trajectories 25', 26
' is also a recording track for video signals. On the other hand, the rotary heads 27 and 28 hold the magnetic tape l in a section R having a width WA.
When scanning A, a time-base compressed PCM audio signal is supplied, so that among the scanning trajectories 27', 2B',
Hatched parts 27' and 28' are time axis pressure @PCM
This is a recording track for audio signals.

Next, the video signal and time axis compression P in this example are
A specific example of a CM audio signal recording and reproducing system will be described with reference to FIG. In the same figure, 29.30 is an input terminal, 31.32 is a recording amplifier, 33 to 36 are switching devices, and 3
7 to 40 are rotary transformers, 41.42 is a preamplifier, 43.44 is an output terminal, and 25 to 28 are respective rotary heads shown in FIG.

In Figure 8, the switches 33 and 34 are closed to the contact R side during recording and to the contact P side during playback. Also, switch 35.36
When the rotary head 25, 26 starts scanning the magnetic tape, the head switching pulse 8 W vc switches contact point a to b and vice versa.

FIG. 9 is a timing chart showing the video signal and time-base compressed PCM audio signal of FIG. 8.

Next, the operation of the specific example shown in FIG. 8 will be explained using FIGS. 6 and 9.

First, during recording, the rotary head 25 rotates the magnetic tape
When scanning starts, the head switch SW becomes "H" and the switches 35 and 36 close to the contact a side. At this time, the video signal V is continuously supplied from the input terminal 29, and this video signal V is sent to the recording amplifier 31. Switch 33
, 35, the rotating head 2 via the rotary transformer 37
Please supply 5vc.

When the rotary drum 2 rotates by an angle α and the rotary head 27 starts scanning the magnetic tape l, signals are sent from the input terminal 30 to the recording amplifier 32 and the switching devices 34 and 36 during the period when the rotary drum 2 rotates by an angle θ. A time-base compressed I'CM audio signal is supplied to the rotary head 27 via the rotary transformer 39.

Thereafter, when the rotary head 25 finishes scanning the 180" winding of the magnetic tape 1 by one rotation of the drum 20 times, the head switching pulse becomes 8WtX"L", and the switch 35.3
Switch 6 to contact b@.

As a result, by scanning the rotary head 25, a recording track 25' of the video signal V of the section RvVCl field is formed on the magnetic tape 1 as shown in FIG. time within the rotation period of the angle θ! By supplying the compressed PCM audio signal A, the length of the section on the magnetic tape L is increased! A recording track 2f of the time axis compressed PCM audio signal is formed. In addition, this time-base compressed PCM audio signal for each field period is θ/180.
It is an intermittent signal whose time axis has been compressed at a ratio of ”.

As described above, when the head switching pulse SW becomes "L" and the switch 35, 36 switches the contact b911Vc, the video signal V is transmitted to the rotating head 2 via the rotary transformer 38.
6, and to the rotary head 28 which starts scanning the magnetic tape l after an angle α delay from the rotary head 26: During the period when the rotary drum 2 further rotates by an angle θ, the magnetic tape is supplied to the rotary transformer 40. Time axis compression PC
M audio signal A is supplied. As a result, as shown in FIG. 7, the recording track 26' of the video signal V in the section RvVcl field also becomes
A recording track 28' of the audio signal is formed.

The above operation is repeated every 201 rotations of the rotating drum,
On the magnetic tape l, as shown in FIG.
Recording tracks of the video signal V for each c1 field are sequentially formed, and at the same time, recording tracks of the time-base compressed PCM audio signal are sequentially formed in the section RA.

Next, the operation during playback will be explained.

In this case, the recording tracks 1 and 7 shown in FIG.
1lVc closed.

Now, the rotating head 25 is moving to the recording track 25' (Fig. 7).
When the reproduction scan starts, the head switching pulse SW is ``H'' at this point, the switches 35 and 36 are closed to the contact a side, and the video signal V reproduced from the recording track 25' is Rotary transformer 37, switch 35.33
, are supplied to an output terminal 43 via a preamplifier 41.

Further, after the rotary head 25 starts reproducing and scanning the recording track 25' and the rotary drum 2 rotates by an angle α, the rotary head 27 starts reproducing and scanning the recording track 2f on the magnetic tape l, and the rotary drum 2 rotates at an angle of While rotating by θ, the time axis compressed PCM audio signal A is reproduced from the recording track 27'. This time-base compressed PCM audio signal is supplied to an output terminal 44 via a rotary transformer 39, a switch 36, 34, and a preamplifier 42.

Further, when the rotary drum 2 rotates and the rotary head 25 completes the reproducing scan of the recording track 25', the head switching pulse SW becomes "L" and switches to the contact side of the switch 35°361. During this time, the rotary head 25 reproduces the video signal V of the 1 field.

Next, in the same manner, the rotary head 26 moves to the recording track 26.
1 (Fig. 7) is reproduced and scanned to obtain the video signal V of l field.
is played back, while the rotating head 28 is moving the recording track 28.
# (FIG. 7) is reproduced and scanned to reproduce the time axis compressed PCM audio signal A.

Thereafter, such operations are repeated, and a continuous video signal V is obtained at the output terminal 43, and an intermittent time-base compressed PGM audio signal is obtained at the output terminal 44. These reproduced signals are processed in the same manner as in the prior art described above. Also,
At the time of reproduction, each of the rotary heads 25 to 28 is subjected to racking control (51C1) so that it accurately reproduces and scans a predetermined recording track, as in the prior art described above.

As described above, in this embodiment, the video signal and the time-axis compressed PCM audio signal are both recorded at a high recording density in different areas divided in the width direction of the magnetic tape by a rotating head. You can also play these signals.

By the way, in the above embodiment, in FIG. 7, the section Rv
Recording track and section RAVC of video signal formed by FC
The relative positional relationship between the time axis pressure and the recording track of the PCM audio signal was arbitrary, but the rotating head 25.2
Match the azimuth angles of 7 and also rotate the head 26.2.
8 and the rotating head 25.
．． 26 and the pair of rotary heads 27 and 28, and furthermore, the angle α corresponding to the delay amount of the time-base compressed PCM audio signal with respect to the head switching pulse SW is 2nπ+α.
As a result, in FIG. 7, on the extension line of the recording track of the video signal formed in the section Rv, a recording track of the time-axis compressed PCM audio signal with the same magnetization direction is formed in the section RAVc, and the conventional audio It is compatible with VTRs using the signal overlap recording method.

In addition, in FIG. 6(a), the angle α corresponding to the lag of the time axis subline PCM audio signal with respect to the VC tilt angle α and the head switching pulse 8WK is set to 180'' (π), that is, the rotary head 25. 28 are arranged in the direction of the rotation axis, and the rotation heads 26, 27 are arranged in the direction of the rotation axis), and the rotation heads 25, 27 and 26, 28 are connected in parallel, respectively, as shown in FIG. The recording track pattern shown in Fig. 7 can be formed on the magnetic tape l by the recording/reproducing system.That is, in Fig. 4, the rotary transformer 17 is connected in parallel with the rotary heads 25°27, A rotary head 26.28 is connected in parallel to the transformer 18.Thereby, the rotary head 25.28 and the rotary head 26.27 scan the magnetic tape l alternately.In this case, the rotary head 25.28 scans the magnetic tape l. While scanning Hl, the head switching pulse SW becomes II Hl'', and the switch 11.12 switches to contact b.
Closed to a, the video signal V is rotated by a rotating head of 25.27 degrees, and the time axis compressed PCM audio signal is rotated by a rotating head of 26 degrees and 28 degrees.
However, the video signal ■ is supplied to the rotary head 25,
In addition, the time axis compressed PCM audio signal co-rotating head 28 generates sections Rv, RA (FIG. 7) rc on the magnetic tape l.
Be recorded respectively. The rotating head 26.27 is a magnetic tape l.
During the scanning period, the head switching pulse SW becomes "L" and the switch 11.12 closes to the contact a@, and in the same way, the rotating head 26Vc outputs the video signal V, and the rotating head 26Vc also outputs the video signal V. The time-base compressed PCM audio signal is recorded on magnetic tape IVC. In this way,
A recording and reproducing system in the conventional audio signal overlap recording method can be used.

In this case, it goes without saying that the recording current is optimized in accordance with the inductance due to the parallel connection of the rotary heads 25, 27 and 26, 28.

The present invention has been described in detail above, but the present invention is applicable not only to time-base compressed PCM audio signals, but also to other information signals such as data information, or multiplexed signals of arbitrary information signals. [Effects of the Invention] As explained above, according to the present invention, the angle of winding the magnetic tape around the rotating drum can be made smaller compared to the conventional audio signal overlap method. In this way, two information signals can be recorded in different areas divided in the width direction of a magnetic tape using respective rotary heads, and furthermore, these information signals can be reproduced.
1) The moving path of the magnetic tape pull-out member can be shortened, reducing the required plane area of the mechanical system and simplifying the mechanical system. (2) The rotational load on the magnetic tape rotating drum is reduced. (3) The contact area of the magnetic tape with the fixed drum is reduced, reducing the sliding noise of the magnetic tape. Tape load can be reduced when the tape runs at high speed.

You can get remarkable effects such as:

[Brief explanation of drawings]

1 to 5 show a magnetic recording and reproducing device using a conventional audio signal overlap recording method, in which FIG. 1 is a perspective view showing the cylinder portion, FIG. 2 is a plan view seen from the rotation axis direction of FIG. FIG. 3 is a pattern diagram showing recording tracks of a magnetic tape, FIG. 4 is a block diagram showing a recording/reproducing system, FIG. 5 is a timing chart showing the operation of FIG. 4, and FIGS. 6 to 9 are diagrams of the present invention. 6(a) and (b) are a plan view and a perspective view of the clinder portion, FIG. 7 is a pattern diagram showing recording tracks on a magnetic tape, and FIG. 9 is a block diagram showing a specific example of a recording/reproducing system, and FIG. 9 is a timing chart showing the operation of FIG. 8. l...magnetic tape, 2...rotating drum, 25°26.27.28...rotating head. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 (a) %

Claims (1)

[Claims] The magnetic tape is divided into first and second areas in the width direction, and the first area has a recording track for a first information signal, and the second area has a recording track for a second information signal. In a magnetic recording and reproducing apparatus, each of which is formed diagonally on the magnetic tape, a first rotary head group for recording and reproducing the first information signal and a second rotating head group for recording and reproducing the second information signal. The first,
The scanning start position of the second rotating head group on the magnetic tape is varied in the width direction of the magnetic tape, and the winding angle of the magnetic tape around the rotating drum can be set to approximately 180 degrees. A magnetic recording/reproducing device characterized by comprising: