JPS60224103A - Multiplex information recording and reproducing device - Google Patents

Abstract

PURPOSE:To record the information on a field of 1CH in a 270 deg. revolving angle range in the case of the nCH recording, for example, by distributing (n+1) units of rotary magnetic heads to a tape guide equidistantly and winding a magnetic tape by 360 deg.(n-1)/n or more. CONSTITUTION:When the 3CH recording is desired, four rotary magnetic heads are distributed equidistantly to a tape guide drum. Then a magnetic tape is wound round the drum by 270 deg. or larger. Each head records the information on a field of 1CH to the magnetic tape in the form of a locus of magnetization within a 270 deg. revolving angle range. The information on 3CH are supplied in parallel as well as to three rotary magnetic heads having a contact with the magnetic tape respectively by switching. Thus no effect is given to an existing format.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic recording and reproducing apparatus that records and reproduces video signals by winding a magnetic tape around a tape guide drum at a predetermined angle.

Conventional configuration and its problems Currently, household magnetic recording and reproducing devices (hereinafter referred to as VTRs)
All of the systems that have been put into practical use are basically one-channel recording and reproducing. Although the extension of the length was achieved with great momentum, the number of records for multiple channels in the same time period was V.
There is no other way than to prepare a TR.

However, it is not impossible to record multiple channels with one VTR. One example is the system shown in FIGS. 1 to 3.

In FIGS. 1 to 3, reference numeral 1 denotes a rotating magnetic head device as a whole, which includes rotating magnetic head assemblies 2 and 2', an upper drum 4, and a lower drum 3, which are arranged at a rotation angle of approximately 18o0. The magnetic tape 6 is connected to the rotating magnetic head assembly 2.
and 2' are inclined with respect to the rotating surface and are in contact with each other over a rotational angle range of approximately 18oO. The magnetic head assembly 2 has three magnetic heads Ha, Hb, Ha,
The magnetic head assembly 2' also has three magnetic heads Ha.
', Hb', and Ha'. 6° indicates the running direction of the magnetic tape, and 7 indicates the rotating direction of the tape guide drum.

The three magnetic heads Ha, Hb, and Ha are arranged with a height difference of h and a circumferential position difference of 8, respectively. If the first information A is supplied to the magnetic heads Ha and Ha', the second information B is supplied to Hb and Hb/, and the third information C is supplied to He and Hc', information A is supplied to TAL and TA2,
Information B is TBL, TB2..., information C is TCl
, TC2, and so on.

This recording method does not form adjacent tracks in sequence like in conventional home VTRs, so if you try to record azimuthally overlapping at the position of the recording pattern in FIG. 4, for example, the TC track will be changed as shown in FIG. TA forms a wide track called T3, and TA forms a narrow trunk called T1.
B forms a track T2 having an intermediate width. If a guard band is provided, this problem will not be solved, but the recording density will be completely inferior. The reason why we did not adopt the method of recording adjacently and sequentially is that the value of 8, h
This is because there is a limit to the value of and is not realistic. Also, as is clear from this example, six rotating magnetic heads are required to record three pieces of information. Heat theory, magnetic tape 36
There is also a method of using three rotating magnetic heads by winding the magnetic head around 0 degrees, but this involves the conventional one-head system, which has problems unique to this one-head system.

Purpose of the Invention The present invention enables high-density recording of azimuth recording without guard panning, similar to home VTRs, and is suitable for n-channel recording (
The present invention provides a multiplex information recording/reproducing device in which n+1 ) magnetic heads are sufficient.

Structure of the Invention According to the present invention, for example, when three-channel recording is desired, rotating magnetic heads are arranged at equal intervals on four tape guide drums, and more than 2,700 magnetic tapes are wound. Each head has 2
In a range of 700 rotation angles, information of one field of one channel is recorded on the magnetic tape as one magnetization locus. The three channels of information are supplied in parallel, and switching is performed so that the information is supplied to each of the three rotating magnetic heads in contact with the magnetic tape.

DESCRIPTION OF EMBODIMENTS As an embodiment of the present invention, a three-channel recording system will be described below with reference to the drawings.

FIG. 7 shows four rotating magnetic heads Ga and Gb.

A tape guide drum 14 is shown in which Gc and Gd are arranged in 900 divisions. The magnetic tape 11 runs in the direction of arrow 6,
27° on the outer periphery of the tape guide drum 14.

It has been rolled up over the years. 12 and 13 are tape guide posts. Since the tape guide drum 14 is rotating in the direction of arrow 7 at a rotation speed of 270 or-pm,
/4 rotation takes 1/60 seconds. Each rotating magnetic head forms a magnetization locus by converting one field of information into one track of the magnetic tape 11 by 3/4 rotation of the tape guide drum 14. This tape guide drum 14
FIG. 10 shows the magnetic tail pattern recorded using the magnetic tail, and FIG. 11 shows the information timing chart of the Raku rotary insect head. Figures 12 to 15 refer to P of Figure 11.
1, P2, p3, and p4, respectively.

H3, H4, H5...Hlo is the flow of the first information H, 11, 12... Is...Is is the second flow of information I, and Ko is 1. 2. ...Team K7 is the third
This is the flow of information. Focusing on the rotating magnetic head Ga, information such as 1-Hs-15- and 5-H9 is sent to I1-. Tsumashi 1st information H1 2nd information■,
The third information K is sent sequentially. The other rotating magnetic heads also receive information on H, 1, and H, 1, sequentially, although the timings are different. In the case of a Ga rotating magnetic head, information is switched during the g00 rotation interval from FIG. 15 to FIG. 12, and new information is sent to the rotating magnetic head again from FIG. It will be washed away during the section. Therefore, the rotating magnetic head Ga is between Pl and P4, and Gb is between p4.
-p3, Gc between p3 and p2, and Gd between p2 and p1, so that information is always passed to three rotating magnetic heads in parallel. Focusing on information H,
G c -G d -G a -G b -G c -
G d - Ga and the rotating magnetism that transmits that information, Rad, changes. Looking at the magnetic tape pattern, the first
It can be seen that the information H1, the second information (2), and the third information K are repeatedly formed alternately. The recording order is from the state shown in Fig. 12 to Ga (head) - 1 (information), from Fig. 13 to Gd - H4, from Fig. 14 to G c - J 3 and 1
From Figure 6, Gb-2. Returning to Figure 12 again, G2-H5
becomes. In terms of tape pattern, adjacent tracks are scanned one after another, and adjacent trunks are Ga-G d-
Since the track pattern of the rotating magnetic head is Gc-Gb-Ga, for example, if Ga and Gc are set to positive azimuth Cid and Gb is set to negative azimuth, azimuth recording is possible and high density recording is possible.

A block diagram of the state of PP in FIG. 11 will be explained with reference to FIG. 16. 15, 16, and 17 are video signal input terminals, and the input H, I, and information signals are frequency modulated by a 18° 19.20 frequency modulator, amplified by a 21° 22.23 recording amplifier, and 24 , 25°26 recording@), playback (I
)) Go through the switch. 27.28° 29.30 is a head switch, which detects the rotation of the tape guide drum 14 and sends information signals to the rotating magnetic heads 33.34, 35.36 based on the control signal 32 obtained from the control signal 32. selectively switched and supplied. In this way, the three information signals H, J, and the rotating magnetic heads Ga, Gb, and Gc
, G d.

During playback, the signals obtained from the head switches 27 to 3o are output via the playback amplifiers 37, 38, 39 and frequency demodulators 40, 41, 42 because the recording/playback switches 24, 25, and 26 are switched. Leading to terminals 43, 44, 45. In this way, the information signals are H to N, J to M, K
is output to L.

Next, to explain the compatibility between the tape guide drum 14 of the present invention shown in FIG. 7 and the two-head type tape guide drum, the two-head type tape guide drum 1 shown in FIG.
o is a rotating magnetic head Fa.

Fb is arranged at 180°, and the magnetic tape 11 guided by the tape guide guide post 12.13 is wound around the tape guide drum 1o over 180° and runs. The rotation speed of the tape guide drum 10 is 18oOr-p.
-m, the diameter D1 of the tape guide drum 1o is 3 of the diameter D2 of the tape guide drum 14 of the four-head type shown in FIG.
/2 times.

If the lead angle and tape speed are also the same, the two are completely compatible. The tape speed has a 2-hour mode and a 6-hour mode, as is the case with one of the formats of home VTRs that are currently popular, and if you try to achieve this with two heads, you will need a narrow-track head that is optimal for the 6-hour mode. becomes. If this head is used to perform 2-hour mode recording at a high tape speed, the tape pattern shown in FIG. 17 will be obtained. This is a 4-head tape guide drum 1
This coincides with the magnetization locus of one piece of information in FIG. 10, which is tape pattern No. 4.

In other words, when the tape shown in Fig. 10 is mounted on the two-head type tape guide drum 1o shown in Fig. 6, the recorded information H
, J, it becomes possible to reproduce any information from within. On the contrary, it is also possible to load the tape shown in FIG. 17 on the four-head type tape guide drum 14 shown in FIG. 7 and play it back.

Next, change the tape speed to 1/3 of the standard speed like 6 hour mode.
, the 2-head tape guide drum 10
The tape pattern is recorded without a guard band, as shown in FIG.

When the tape speed is reduced to 1/3 using the 4-head tape guide drum 14, it is easy to achieve the tape pattern shown in Figure 8 by recording one piece of information K according to the timing chart in Figure 9. It will be easy to understand.

In this embodiment, three pieces of information are recorded, but two pieces of information can be recorded by arranging three heads equally into 1200 pieces and winding the magnetic tape 240°. Similarly, by winding the magnetic tape 360-1 (-7-) times using N heads, it becomes possible to record and reproduce (N-1) pieces of information.

Effects of the Invention The present invention has the following effects as a multiple information recording/reproducing device.

(1) For recording and reproducing N pieces of information, the rotating magnetic head is N+
Since one piece is sufficient, it is very advantageous in terms of cost and component mounting.

(2) Since the rotating magnetic heads are arranged on the same rotation plane, it is advantageous in terms of head indexing, mounting, and machining.

(3) Since it is an adjacent track sequential recording method, high-density recording is possible due to the azimuth effect.

(4) Recording one piece of information for a long time at a low tape speed can also be achieved by high-density recording using the azimuth effect.

(5) Due to multiple information recording, when the number of rotating magnetic heads is increased, the winding angle of the magnetic tape around the tape guide drum also increases, making it possible to downsize the tape guide drum, contributing to downsizing of equipment.

The four-head type three information recording system described in this embodiment has the advantage of being compatible with the 2-hour and 6-hour modes of existing home VTRs and being usable without affecting existing formats.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a conventional tape guide drum, Fig. 2 is a plan view of a conventional tape guide drum, Figs.
Fig. 5 is a diagram of a conventional tape pattern, Fig. 6 is a plan view of a two-head type tape guide drum, and Fig. 7 is a plan view of a four-head type multiple information recording tape guide drum showing an embodiment of the present invention. , Figure 8 is a tape pattern diagram for long-term single information recording, Figure 9 is a timing chart for single information long-term recording, Figure 10 is a tape pattern diagram for multiple information recording, and Figure 11 is a tape pattern diagram for multiple information recording. Timing chart, 1st
Figures 2 to 15 are phase relationship diagrams of the rotating magnetic head of a tape guide drum for four-head multiplexed information recording, Figure 16 is a block diagram, and Figure 17 is a tape pattern for a two-head tape guide drum at high tape speed. It is a diagram. 1o... Tape guide drum, 14...
・Tape guide drum, Ga, Gb, Gc, Gd・
...Rotating magnetic head, H, 1, K...Input information. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 4 Figure 6 Figure 7 Figure 8 Figure 9 H% ratio Figure 10 Figure 11 P Mak V Figure 12 Figure 16 Figure 17

Claims (1)

[Claims] n (an integer of 3 or more) rotating magnetic heads provided on a rotating body at equal intervals; the rotating magnetic heads are rotatably built in;
-) The tape guide drum is wound diagonally over a range of 100 degrees, and each magnetic head sequentially records and reproduces substantially one field or one frame of video signals onto the magnetic tape each time the rotating magnetic head rotates (□). have the means,
(n-1) information signals are sequentially supplied to the n rotating magnetic heads in parallel, and the (n-1) information signals are sequentially distributed on the magnetic tape for each rotation of the rotating magnetic head. A multiple information recording/reproducing device characterized in that a magnetization trajectory is formed.