JPH03212080A - Magnetic recording device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic recording device that simultaneously records signals of a plurality of channels on a magnetic tape.

[Conventional technology]

Generally, when recording a video signal digitally, a significantly wider band is required than when conventionally recording a video signal by FM modulating it and recording it in analog form.

In addition, in recent years, EDT V (extended d
efinition television) and HD
TV (high definition tele)
Development of new broadcasting systems such as ``Vision'' is underway, and video tape recorders (VTRs) that record these signals in analog form require a wide band. Moreover, a VTR that digitally records the above-mentioned signals requires an even wider band. In response to this, the following countermeasures are being considered.

■ Improve recording density by using new materials such as metal tape and metal heads.

■ Divide the video signal into multiple channels and record.

■ Increase the rotation speed of the rotating drum to increase the relative speed between the magnetic tape and the magnetic head.

Here, based on FIGS. 6 and 7, the video signal is
A conventional example of dividing and recording into channels will be explained as follows.

As shown in Fig. 6, magnetic helads a1, a2, bl, b
2, C1, C2, dl, and d2 are arranged on the rotating drum 21. The magnetic heads a1 and a2 are installed on the periphery of the rotating drum 21 at an interval of approximately 180°. The magnetic heads b1 and b2, the magnetic heads c1 and 02, and the magnetic heads di and d2 are also placed at an interval of 180° so as not to overlap each other. The azimuths of the magnetic heads a1, cl, a2, and C2 and the magnetic helads bl, dib2, and d2 are set, for example, in opposite directions.

This causes the azimuths of adjacent tracks to be in opposite directions, making it possible to perform high-density recording without guard panning. Note that the magnetic tape 22 has a diameter of 180 mm.
It is wrapped around the rotating drum 21 at a wrapping angle of '.

As described above, when the magnetic head is placed on the rotating drum 21, the magnetic tape 22 is placed on the magnetic tape 21 at the timing shown in FIG.
The video signal is divided into four channels and recorded.

That is, the signal of channel (hereinafter referred to as CH) 1 is supplied to the magnetic head a1, and the signal of the magnetic head a is supplied to the magnetic tape 22.
Recording starts after 1 makes contact. Assuming that the rotating drum 21 and the magnetic tape 22 are rotating in the direction shown in FIG. 6, when the magnetic head a1 rotates 45 degrees from the state shown in FIG.
Contact 2. At this time, the CH2 signal is supplied to the magnetic head bl to record on the magnetic tape 22.

When the magnetic head a1 rotates 90', the magnetic head C
1 contacts the magnetic tape 22. At this time, the magnetic head c
1 and records on the magnetic tape 22.

When the magnetic head a1 has rotated 135 degrees, the magnetic head di comes into contact with the magnetic tape 22. At this time, the CH4 signal is supplied to the magnetic head d1 to record on the magnetic tape 22.

When the magnetic head a1 has rotated 180 degrees, the magnetic head a2 comes into contact with the magnetic tape 22. At this time, the CHI signal supply destination is switched from the magnetic head a1 to the magnetic head a2. Then, the CHI signal is supplied to the magnetic head a2 and recorded on the magnetic tape 22.

When the magnetic head a1 has rotated 225 degrees, the magnetic head b2 comes into contact with the magnetic tape 22. At this time, the destination of the CH2 signal is switched from the magnetic head bl to the magnetic head b2. Then, the CH2 signal is supplied to the magnetic head b2 and recorded on the magnetic tape 22.

When the magnetic head a1 rotates 270 degrees, the magnetic head c2 comes into contact with the magnetic tape 22, and the CH3 signal is switched from the magnetic head cl to the magnetic head c2. Then, the CH3 signal is supplied to the magnetic head b2 and recorded on the magnetic tape 22.

When the magnetic head a1 has rotated 315 degrees, the magnetic head d2 comes into contact with the magnetic tape 22, and the CH4 signal is switched from the magnetic head d1 to the magnetic head d2. Then, the CH4 signal is supplied to the magnetic head d2 and recorded on the magnetic tape 22.

When the magnetic spatula F'a1 rotates 360 degrees (one rotation), the magnetic spatula a1 comes into contact with the magnetic tape 22, and the CH1 signal supply destination is switched from the magnetic head a2 to the magnetic spatula a1. Then, the CHI signal is supplied to the magnetic head a1 and recorded on the magnetic tape 22.

Thereafter, by repeating the above operating procedure, the desired video signal is divided into four channels and recorded. Therefore, since the video signal is divided into four channels, the band per track can be compressed and recorded to 1/4 of that in the case of one channel recording.

[Problem to be solved by the invention] However, in the above conventional magnetic recording device, N (positive integer)
In order to record the signal of the channel continuously, a total of 2
N magnetic heads are required.

Accordingly, the same number of ancillary parts such as a rotary transformer and ancillary circuits as magnetic heads are required.

Furthermore, as the number of channels increases, the number of parts described above also increases, resulting in a large-scale magnetic recording device, which has the problem of becoming extremely expensive.

[Means for Solving the Problems] In order to solve the above problems, the magnetic recording device according to the present invention provides a magnetic recording device that is close to the periphery of a rotating tram, where m is an integer of 2 or more and n is an integer of 3 or more. A total of n'Mi magnetic heads are arranged so that the central angle is 360°/n, and the winding angle is approximately 36°.

A tape-shaped magnetic recording medium, for example, a magnetic tape, is wound around the rotating drum so that x(n-1)/n, and (
It is characterized in that signals of mX(n-1) channels are recorded on the magnetic recording medium by m×n) magnetic heads.

[For production]

According to the above configuration, a set of m magnetic heads is arranged around a rotating drum provided with a total of n sets of magnetic heads so that the winding angle is approximately 360°X(n-1)/n. , a tape-shaped magnetic recording medium is wound around it. Therefore, since mX(nl) magnetic hands are always in contact with the magnetic recording medium, signals of mX(n-1) channels can be continuously recorded.

In addition, when (m×n) is an even number, if the azimuths of adjacent magnetic heads placed on the periphery of the rotating drum are set in opposite directions, it is possible to easily record the information on the magnetic recording medium in a guard-handless manner.
High-density azimuth recording is possible.

〔Example〕

An embodiment of the present invention will be described below based on FIGS. 1 to 4.

The first example of the configuration of the magnetic helad of the magnetic recording device according to the present invention is as follows.
As shown in the figure. As shown in the same figure, magnetic heads A1, A2
, B1, B2, C1, and C2 are installed at the periphery of the rotating drum 11. The installation positions of magnetic heads At and A2 (hereinafter referred to as AMi magnetic heads), the installation positions of magnetic heads B1 and B2 (hereinafter referred to as 8 sets of magnetic heads), and the installation positions of magnetic heads C1 and C2 (hereinafter referred to as 0 sets of magnetic heads). (referred to as magnetic heads) are installed on the periphery of the rotating drum 11 so that their center angles are 120°.

The magnetic heads A1 and A2 are arranged close to each other on the circumference of the rotating drum 11, and are configured to have a step corresponding to the track width. The magnetic heads of group B and the magnetic hands of group 0 are also constructed in the same manner as the magnetic heads of group A. In addition, magnetic head A
1, B1, and CI azimuth, and magnetic head A2,
The azimuths of B2 and C2 are set in opposite directions.

As shown in FIG. 1, a magnetic tape 12 serving as a magnetic recording medium is wound around a rotating drum 11 at a winding angle of about 240 degrees. The rotating drum 11 is, for example, a conventional
/3 times the speed, i.e. 4/3x1800=2400 [r
pm) in the direction shown in the figure.

Here, four channels of signals are sent to the magnetic tape by magnetic heads A1, A2, B1, B2, C1, and C2.
2 will be explained based on FIGS. 2 to 4 as follows.

As shown in FIG. 3, the analog luminance signal Y and two color difference signals PR'PR obtained from the input video signal are
Each is input to the A/D conversion circuit 1. The A/D conversion circuit 1 converts the luminance signals Y, Y, and Y based on the clock signal.
and two color difference signals P, .P, are A/D converted into digital signals. Note that the above clock signal is generated in the PLL clock generator 4 based on the input synchronization signal 5YNC. The PLL clock generator 4 generates a timing signal in addition to a clock signal.

A luminance signal Y, and two color difference signals P, -P.

The outputs from the A/D conversion circuit 1 corresponding to the above are respectively sent to the channel division signal processing circuit 2.

In the channel division signal processing circuit 2, the signal is divided into four channels of signals CHI to CH4 based on the timing signal, and signal processing necessary for recording is performed.

The four outputs from the channel-divided signal processing circuit 2 are sent to the modulation circuit 3, respectively. In the modulation circuit 3, the PLL
Based on the timing signal from the clock generator 4, signals of four channels CHI to CH4 are respectively modulated.

The output of the modulation circuit 3 (hereinafter referred to as a modulation signal) modulated corresponding to each signal of CHI to CH4 is sent to a switch circuit 8.
It is now sent to As shown in Figure 3, C
The HI modulation signal is sent to SWI SW5 in the switch circuit 8.
, and 5W9(7)- contacts, respectively. The modulation signal of CH2 is sent to SW3 in the switch circuit 8.
, SWl, and one contact of 5WII. The modulation signal of CH3 is connected to one contact of SW2, SW6, and 5WIO (7) in the switch circuit 8, respectively. The modulation signal of CH4 is connected to one contact of SW4, SW8, and 5W12 in the switch circuit 8, respectively.

The other contact of SWI~5W12 is connected to the recording amplifier 7 in the latter stage.
and each modulation signal of CHI to CH4 is
The magnetic tape 1 is transferred to the recording amplifier 7 via the magnetic head.
It is designed to be amplified to the extent that it can be recorded on 2. That is, the other contact of SWI.2 is connected to the input of the recording amplifier 7a in the recording amplifier 7, the other contact of SW3.4 is connected to the recording amplifier 7b, and the other contact of SW5.6 is connected to the input of the recording amplifier 7c. It is connected to the. Also, SWl・
The other contact of SW 8 is connected to the recording amplifier 7d in the recording amplifier 7, and the other contact of SW9 and SW 10 is connected to the recording amplifier 7e.
The other contact of 5WII.12 is connected to the recording amplifier 7f. Each output of the recording amplifiers 7a to 7f is connected to the magnetic head At-C2.

In addition, 2 connected to each input of the recording amplifiers 7a to 7f
Two spinches are never both in the ON state at the same time. For example, regarding SWI-2, when SWI is in the ON state, SW2 is in the OFF state. On the contrary, S
When W2 is in the ON state, SWl is in the OFF state. Furthermore, among the three sets of magnetic heads A to C, the recording signal, which is the output of the recording amplifier 7, is always sent to only one set. A signal is being sent.

For example, in the case of magnetic heads of group A, corresponding recording signals are sent to magnetic heads A1 and A2, respectively, and are recorded on the magnetic tape 12.

Switching of 5WI-3WI2 is performed under the control of SW timing generator 5. That is, P
The above switching is performed based on the timing signal output from the LL clock generator 4. This timing signal is also used to control various servo mechanisms 6 of the magnetic recording device.

The recording operation on the magnetic tape 12 by the magnetic heads A1 to C2 will be explained below.

First, only SWI and SW3 are turned ON, and the CHI recording signal is supplied to the magnetic head A1.
The recording signal of CH2 is supplied to the magnetic head A2. Then, the magnetic heads of group A (A1-A2) are connected to the magnetic tape 12.
As shown in Figure 2, the CHI
Two recording signals are recorded on the magnetic tape 12. The ON state of SWI and SW3 indicates that the magnetic head of the next B group (Bl
- B2) is held until it comes into contact with the magnetic tape 12.

The rotating drum 11 rotates in the direction shown in FIG.
When the magnetic head i rotates 120', SWl and SW3 are turned off, and only SW6 and SW8 are turned on. At this time, the magnetic heads of group B come into contact with the magnetic tape 12.

Along with this, the recording signal of CH3 is supplied to the magnetic head B1, the recording signal of CH4 is supplied to the magnetic head B2, and these recording signals are recorded on the magnetic tape 12. In addition, the ON state of SW6 and SW8 is
The rotating drum 11 is held until it has rotated an additional 120 degrees.

When the magnetic head of group A rotates 240 degrees, SW6 and SW8 are turned off, and SW9 and 5W11 are turned off.
only is in the ON state. At this time, the magnetic head of set 0 comes into contact with the magnetic tape 12.

Along with this, the supply destination of the recording signal of CH1 is switched from the magnetic head Al to the magnetic head FCI, and the
The supply destination of the H2 recording signal is switched from the magnetic head A2 to the magnetic head C2, and the recording signal is transferred to the magnetic tape 12.
These recording signals are recorded. In addition, SW9 and 5
When the WII is in the ON state, the rotating tram 11 is further
° Holds until rotated.

When the magnetic head of group A rotates 360 degrees, SW9 and 5WII turn OFF, and SW2 and SW4 turn OFF.
only is in the ON state. At this time, the magnetic nodes of group A come into contact with the magnetic tape 12.

Along with this, the supply destination of the recording signal of CH3 is switched from the magnetic head Bl to the magnetic head A1, and the
The supply destination of the H4 recording signal is switched from the magnetic head B2 to the magnetic head A2, and these recording signals are recorded on the magnetic tape 12. Note that the ON state of SW2 and SW4 is maintained until the rotating drum 11 further rotates by 120 degrees.

When the magnetic head of group A rotates 480 degrees, SW2 and SW4 are turned off, and only SW5 and SW7 are turned on. At this time, the magnetic heads of group B come into contact with the magnetic tape 12. Along with this, the supply destination of the CHI recording signal is switched from the magnetic head C1 to the magnetic head B1, and the supply destination of the CH2 recording signal is switched from the magnetic head C2 to the magnetic head B2, and the recording signal is transferred to the magnetic tape 12. , these recording signals are recorded. Note that the ON state of SW5 and SW7 is maintained until the rotating drum 11 further rotates by 120 degrees.

When the magnetic head of group A rotates 600 degrees, SW5 and SW7 are turned off, and 5WIO and 5W1
Only 2 is in the ON state. At this time, the magnetic nodes of the 0th set come into contact with the magnetic tape 12.

Along with this, the supply destination of the recording signal of CH3 is switched from magnetic head Al to magnetic head C1, and the supply destination of the recording signal of CH3 is switched from magnetic head Al to magnetic head C1.
The supply destination of the recording signal H4 is switched from the magnetic head A2 to the magnetic head C2, and these recording signals are recorded on the magnetic tape 12. In addition, 5WIO and 5W1
The ON state of No. 2 is maintained until the rotating drum 11 rotates a further 120'.

When the magnetic node of group A rotates 720 degrees, 5WIO
and 5W12 are in the OFF state, SWl and SW
Only 3 is in the ON state. At this time, the magnetic heads of group A come into contact with the magnetic tape 12. Along with this, the supply destination of the CHI recording signal is switched from the magnetic head B1 to the magnetic head A1, and the supply destination of the CH2 recording signal is switched from the magnetic head B2 to the magnetic head A2, and the recording signal is transferred to the magnetic tape 12. , these recording signals are recorded.

Note that the ON state of SWI and SW3 means that the rotating drum 1
1 is held until rotated an additional 120°. below,
By repeating the above operations, desired recording can be performed on the magnetic tape 12.

C) 11 recorded on the magnetic tape 12 as described above
~ The track pattern of the recording signal of CH4 is shown below.
The result will be as shown in the figure. CHI to CH4 in the figure correspond to CHI to CH4 in FIG. 2, respectively. In this embodiment, as shown in FIG. 4, the azimuths of adjacent tracks are set to be opposite to each other. For example, if CHl is recorded with L azimuth, CH2 is recorded with R azimuth, CH3 is recorded with L azimuth, and C
H4 is recorded in R azimuth. This makes it easy to perform high-density recording without guard panning.

According to the above embodiment, the tape winding angle of the magnetic tape 12 is set to approximately 240 degrees, and the rotation speed of the rotary drum 11 is set to 4/3 times the normal rotation speed (1800 rpm). The diameter of the rotating drum is 3 times the normal diameter.
/4 times smaller. However, the present invention
Not limited to these various settings, in order to increase the relative speed between the rotating drum 11 and the magnetic tape 12, each channel is divided into N segments, and the rotational speed of the rotating drum 11 is reduced to (4/3) of the normal one. It goes without saying that it is also possible to record by setting it to x N ) times. In this case, it is possible to form the same trunk pattern as when the number of rotations of the drum is set N times higher in the seven-head arrangement shown in the conventional example.

Further, in the above embodiment, a case has been described in which two magnetic heads disposed close to each other on the periphery of the rotating drum 11 form one set, but the present invention is not limited to this, and for example, one set may be formed. The number of magnetic heads is increased to m (m is an integer of 3 or more), and the central angle of the n&l magnetic head is 360°/n.
At the same time, the magnetic tape 12 is wound at the winding angle θ [°] shown below, and mX (nl) channel signals are continuously transmitted onto the magnetic tape 12 using (m×n) magnetic heads. You can also record it.

θ = 360° As shown, a total of 12 magnetic nodes A1, A2, A3, Bl, B
2, B3, C1, C2, C3, and DI, B2, B3
Accordingly, nine channels of signals can be continuously recorded on the magnetic tape 12. Furthermore, at this time, (m×
If n) is an even number, guardless, high-density azimuth recording can be easily performed by setting the azimuths of adjacent magnetic heads in opposite directions. Note that the same reference numerals are used for members having the same functions as those in the above embodiment, and detailed explanations thereof are omitted.

〔Effect of the invention〕

As described above, the magnetic recording device according to the present invention includes a set of m magnetic heads arranged close to the periphery of a rotating drum, where m is an integer of 2 or more and n is an integer of 3 or more. A total of n sets of magnetic nodes are arranged so that the central angle is 360°/n, and the winding angle is approximately 360°.
A tape-shaped magnetic recording medium is wound around the rotating drum so that the ratio of This is a configuration in which data is recorded on a medium.

This makes it possible to simultaneously record signals of many channels continuously without significantly increasing the number of magnetic heads. Also, the rotating column can be made smaller. Therefore, the entire magnetic recording device can be downsized. Furthermore, (m
When ×n) is an even number, azimuth recording can be easily performed, which improves the recording density of the magnetic recording medium and
This also has the effect of reducing the area consumed by the magnetic recording medium.

[Brief explanation of drawings]

1 to 4 show one embodiment of the present invention. FIG. 1 is a diagram schematically showing a configuration example of a magnetic head of a magnetic recording device according to the present invention. FIG. 2 is a diagram schematically showing the timing when four channels are recorded on a magnetic tape in a magnetic recording apparatus having the configuration example of the magnetic head shown in FIG. FIG. 3 is a diagram showing an example of a circuit configuration for recording a video signal in a magnetic recording device having the configuration example of the magnetic head shown in FIG. FIG. 4 is a diagram schematically showing a trunk pattern of four channels of recording signals recorded on a magnetic tape. FIG. 5 shows another example of the structure of the magnetic head according to the present invention, and is a diagram schematically showing a case where recording is performed using four sets of magnetic heads, each set having three magnetic nodules. . FIGS. 6 and 7 show conventional examples. FIG. 6 is a diagram schematically showing a configuration example of a magnetic head of a conventional magnetic recording device. FIG. 7 is a diagram schematically showing the timing when four-channel recording is performed on a magnetic tape in a magnetic recording apparatus having the configuration example of the magnetic head shown in FIG. 7 is a recording amplifier, 8 is a switch circuit, 11 is a rotating tram, and 12 is a magnetic tape (magnetic recording medium).

Claims (1)

[Claims] 1. When m is an integer of 2 or more, and n is an integer of 3 or more, m magnetic heads arranged close to the periphery of the rotating drum are considered to be one set, and a total of n sets of magnetic heads are arranged so that the central angle is 36
A tape-shaped magnetic recording medium is wound around the rotating drum so that the angle is approximately 360° x (n-1)/n, and the winding angle is approximately 360° x (n-1)/n.
1. A magnetic recording device, characterized in that signals of m×(n-1) channels are recorded on the magnetic recording medium using ) magnetic heads.