JPH0415534B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a dubbing method for a rotary head type tape recorder, and in particular to a rotary head type tape that can increase the running speed of a magnetic tape during dubbing and shorten the dubbing time. Concerning a dubbing method for a recorder.

BACKGROUND TECHNOLOGY In recent years, tape recorders such as video tape recorders that use rotating heads have come into widespread use. ing. These commercially available magnetic tapes are produced by dubbing a master magnetic tape on which predetermined magnetic recording has been performed.

By the way, in order to perform rapid dubbing with a conventional audio tape recorder using a fixed head, it is sufficient to simply increase the running speed of the magnetic tape, and thereby a large number of dubbing tapes can be produced in a short time. Ta. However, in order to perform rapid dubbing in a rotary head type tape recorder such as a video tape recorder, simply increasing the running speed of the magnetic tape will affect the scanning locus of the magnetic head and the recording on the magnetic tape due to the recording angle of the video track. Due to the misalignment between the video tracks, smooth dubbing is not possible, and in order to correct this, it is necessary to increase the rotation angle of the magnetic head as well.

Problems to be Solved by the Invention When attempting to dub using the above-mentioned conventional rotary head type tape recorder, the rotation angle of the magnetic head must be increased as described above in order to shorten the time required for dubbing. Due to the structure of the rotating head drum, there is a limit to increasing the rotation angle of the magnetic head, which is impractical. Therefore, by preparing a large number of rotary head type tape recorders, reproducing a master magnetic tape at a constant speed, and supplying the reproduced signal to a large number of rotary head type tape recorders whose magnetic tapes also run at a constant speed, dubbing tapes can be reproduced. Dubbing records were being made. Therefore, in order to perform dubbing recording, a large number of rotary head type tape recorders for dubbing must be prepared, resulting in a problem that a large amount of equipment cost is required. Furthermore, the running speed of the magnetic tape was a steady speed, and the time required for dubbing was the time required to normally play back the master magnetic tape, so the dubbing efficiency was poor compared to the dubbing time of audio tape, which can run at a faster running speed of the magnetic tape. There was a problem.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a dubbing device for a rotary head type tape recorder that solves the above-mentioned problems by simultaneously reproducing a plurality of video tracks recorded on a magnetic tape and recording them on another magnetic tape. purpose.

Means for Solving the Problems In order to solve the above problems, the present invention provides a reproducing device and a recording device each with a plurality of pairs of rotating heads, so that the plurality of magnetic heads of the reproducing device form a predetermined track and magnetically A plurality of video tracks magnetically recorded on a tape are simultaneously played back, and a plurality of magnetic heads of a recording device supplied with a playback signal from the playback device simultaneously dub and record the playback signal onto another magnetic tape. It was configured as follows.

Function: In the dubbing method of the rotary head type tape recorder having the above configuration, a plurality of video tracks (for example, n video tracks) are simultaneously played back and recorded by a plurality of pairs of rotary heads provided in the playback device and the recording device, respectively. As a result, the amount of signals reproduced or recorded when the rotary head makes one revolution is n times that of a conventional rotary head tape recorder (a rotary head tape recorder that has only one pair of magnetic heads). The time required to create a video track of a book is relatively 1/n times longer. Correspondingly, it has become possible to increase the running speed of the magnetic tape, and the discrepancy between the scanning trajectory of the magnetic head and the video track recorded on the magnetic tape due to increasing the running speed of the magnetic tape can be reduced by rotation. This can be corrected by appropriately selecting the diameter of the head drum.

Embodiment FIG. 1 shows a dubbing apparatus using an embodiment of the dubbing method (hereinafter simply referred to as dubbing method) for a rotary head tape recorder according to the present invention. A dubbing device 1 shown in the figure includes a helical scan type reproducing device 2 and a recording device 3. The reproducing device 2 generally includes a rotating head drum 4, a plurality of magnetic heads 5 _-1 to 5 _-10 , a switch means 6 _-1 ,
6 _-1 , regenerative amplifiers 7 _-1 to 7 _-5 , etc. Further, the recording device 3 includes a rotating head drum 8,
A plurality of magnetic heads 9 _-1 to _{9 -10} , switch means 1
0 _-1 to 10 _-5 , recording amplifiers 11 _-1 to 11 _-5 and the like. A master magnetic tape 12 (indicated by a one-dot chain line) on which a predetermined track has already been formed and magnetically recorded is wound around the rotary head drum 4 of the reproducing device 2, and a master magnetic tape 12 (indicated by a dashed line) is wound around the rotary head drum 4 of the recording device 3. A magnetic tape 13 (indicated by a one-dot chain line) is wound thereon.

Here, the arrangement positional relationship of the plurality of magnetic heads 5 _-1 to 5 _-10 with respect to the rotary head drum 4 will be explained below with reference to FIGS. 1 and 2. Note that the playback device 2
The arrangement positional relationship between the rotary head drum 4 and the plurality of magnetic heads _5-1 to _5-10 in the recording device 3 is similar to that of the rotary head drum 8 and the plurality of magnetic heads _9-1 in the recording device 3.
Since the arrangement positional relationship is exactly the same as that of _9-10 , only the arrangement positional relationship in the playback device 2 will be explained, and the explanation of the arrangement positional relationship in the recording device 3 will be omitted. Further, in each configuration of the recording device 3, the components corresponding to the configuration of the reproducing device 2 are indicated by their reference numerals in parentheses. As shown in FIG. 1, the rotating head drums 4 and 8 have a total of 10 magnetic heads _5-1 to _5-10 , _9-1 to _9-1.
0 is placed. Among these, magnetic heads 5 _-1 , 9 _-
1 and magnetic heads _5-6 and _9-6 are rotating head drums 4,
Similarly, magnetic heads 5 _-2 , 9 _-2 , 5 _-7 , 9 _-7 , magnetic heads 5 _-3 ,
_9-3 , _5-8 , _9-8 , magnetic head _5-4 , _9-4 , _5-9 ,
9 _-9 , magnetic heads 5 _-5 , 9 _-5 , 5 _-10 and 9 _-10 also form pairs, respectively. The magnetic heads 5 _-1 to 5 _-10 and 9 _-1 to 9 _-10 forming pairs of the plurality of rotating heads are as follows:
Switch means 6 _-1 provided corresponding to each pair
~6 _-5 , 10 _-1 ~10 _-5 .

The magnetic heads 5 _-1 to 5 _-10 and 9 _-1 to _{9 -10} are arranged as shown in FIG. _5-5 ) are arranged along the inclination angle of the magnetic tape 12 wound around the rotating head drums 4, 8, and each adjacent magnetic head _5-1 to _5-5 , _9-1
The separation distance of _9-5 is selected to be equal to the predetermined pitch of the video track recorded on the magnetic tape 12. The magnetic tapes 12 and 13 are wound around the rotating head drums 4 and 8 along an angle of 180° (not including the overlap angle), and each magnetic head 5 _-1 to 5 _-5 , 9 _-1 to 9 _-5 rotates in the direction of arrow A in the figure, and the magnetic tapes 12 and 13 run in the direction of arrow B in the figure. Further, the diameters of the rotary head drums 4 and 8 are selected to be predetermined dimensions, which will be described later.

Switch means 6 _-1 to 6 _-5 , 10 _-1 shown in Fig. 1
~10 _-5 is a plurality of pairs of magnetic heads 5 _-1 ~5 _-1
0,9-1 to _9-10 are alternately arranged on the magnetic tapes 12 and 1 _, respectively.
The magnetic heads 5 _-1 to 5 -10 and 9 -1 to 9 -10 are switched so that magnetic heads 5 -1 to _{5 -10} and 9 _-1 to _{9 -10} can be brought into sliding contact with magnetic heads 3 for magnetic recording/reproduction. This switch means 6 _-1 to _{6 -5} ,1
0 _-1 to 10 _-5 are respectively reproducing amplifiers _{7 -1 to 7 -5} as shown in FIG _. Each regenerative amplifier 7 _-1 of the reproducing device 2 is connected to
7 _-5 is each recording amplifier 11 _-1 to 11 _-5 of the recording device 3
are connected to each other. When connecting the reproducing amplifiers 7 _-1 to 7 _-5 and the recording amplifiers 11 _-1 to 11 _-5 , the reproducing amplifiers 7 - 1 are connected to each pair of magnetic heads disposed at a predetermined position on the rotary head drum 4 of the reproducing device 2 _{. 1} ～
_7-5 is configured to be connected to recording amplifiers _11-1 to _11-5 connected to each pair of magnetic heads disposed on the rotary head drum 8 of the recording device 3 corresponding to each pair of magnetic heads described above. There is. That is, for example, in the reproducing device 2, a pair of magnetic heads 5 _-1 and 5 _-6
The reproducing amplifier 7 _-1 connected to the recording device 3 is connected to a pair of magnetic heads 9 _-1 and 9 _-6 arranged at positions corresponding to the pair of magnetic heads 5 _-5 and 5 _-6 . The recording amplifier 11-1 is connected to the recording amplifier _11-1 .

In the dubbing device 1 constructed as described above, the running speeds of the magnetic tapes 12 and 13 wound around the respective rotary head drums 4 and 8 and running are selected to be faster than the normal running speed. The diameter of the rotating head drums 4, 8 is kept the same as the predetermined diameter of a general video tape recorder, and the magnetic tape 12, 13 is simply
When the traveling speed of each magnetic head is increased, each magnetic head 5 _-1 to 5 _-1
The scanning loci of ₀ , 9 _-1 to 9 _-10 deviate from the predetermined video track, and good recording and reproduction cannot be performed. However, by selecting the diameters of the rotary head drums 4, 8 to be appropriate dimensions corresponding to the running speeds of the magnetic tapes 12, 13, the above deviation can be corrected. The method for selecting the diameter dimensions of the rotary head drums 4 and 8 will be explained below.

There is a certain relationship between the running speed of the magnetic tape and the diameter of the rotating head drum that winds it (Corona Publishing, "Introduction to Home VTR", Katsuya Yokoyama,
Co-authored by Akira Hirota and Yoshimi Watanabe, see). That is, P=V _t /Nsinθ...(1) The relationships in equations (1) and (2) above hold true. However, θ ₀ : Tape inclination angle when stationary θ : Tape recording angle Vt : Tape speed D : Drum diameter N : Field frequency P : Track pitch. In order for a plurality of magnetic heads to simultaneously reproduce a plurality of video tracks recorded on a magnetic tape and for dubbing onto the magnetic tape, it is necessary to change the track pitch P without changing the tape recording angle θ. That is, if the tape recording angle θ changes, it becomes incompatible with general video tape recorders, and as shown in _{FIG .
0} (the magnetic heads _5-6 to _5-10 are not shown because they are on the back side of the rotary head drum 4), in which a plurality of video tracks are played back or dubbed at the same time, for example, the magnetic head _5-1 and its counterpart 5
_-6 (see Figure 1), the track pitch of the video track formed by this pair of magnetic heads _5-1 and _5-6 is the value shown by arrow _P1 in the figure, and compared with the track pitch of a general video tape recorder. It becomes large. Therefore, from equation (2) assuming θ=constant, V _t /ND=k (constant)...(3) Also, in order to increase the track pitch P, (1)
In the formula, V _t /N is assumed to be large. Therefore, from equation (3), D=1/k·V _t /N (4). Therefore, it can be seen that the diameter of the rotating head drum should be selected to be large enough to satisfy equation (4) in order to increase the tape speed _Vt . Note that the diameter of the rotating head drum is also restricted by the upper limit recording frequency and color signal band recorded on the magnetic tape, so it is not possible to increase the running speed of the magnetic tape by unnecessarily increasing the diameter of the rotating drum. Of course it can't be done. Playback device 2 and recording device 3 shown in FIG.
The rotary head drums 4 and 8 provided respectively are selected to have a predetermined diameter that satisfies the above conditions, and the running speed of the magnetic tapes 12 and 13 is also selected to be an appropriate speed higher than the normal running speed. Therefore, a plurality of magnetic heads 5 _-1 to 5 arranged on the rotating head drum 4
_-10 accurately scans the video track recorded on the magnetic tape 12 and outputs a reproduction signal, and a plurality _{of magnetic heads 9--9-10 arranged} on the rotary head drum 8 scan a predetermined video track on the magnetic tape 13. to perform dubbing recording.

Next, the operations and functions of each component when the dubbing apparatus 1 having the above configuration performs dubbing recording will be described below. The rotary head drum 4 of the reproducing device 2 and the rotary head drum 8 of the recording device 3 are rotated synchronously at a predetermined rotational speed by a drive mechanism (not shown). Moreover, the switching means 6 _-1 to 6 _-5 of the reproduction device 2
are configured to switch in synchronization with the switching means 10 _-1 to 10 _-5 of the recording device 3. When the rotary head drum 4 rotates 180 degrees in the playback device 2, one of the magnetic heads _5-1 to _5-5 on one side of the plurality of pairs of magnetic heads will read five videos of the master magnetic tape 12 on which magnetic recording has already been performed. truck
A ₁ to _{A 5} (shown in FIG. 3) are scanned simultaneously to reproduce the recorded signal. In this reproducing process, the magnetic tape 12 is running at a speed higher than the normal running speed, but since the diameter of the rotary head drum 4 is appropriately selected as described above, the reproducing process is carried out smoothly. Further, the switch means _6-1 to _6-5 connect the magnetic heads _5-1 to _5-5 , which perform regeneration processing, to the regenerative amplifiers _7-1 to 7-5.
7 Connected to _-5 . Therefore, magnetic head 5 _-1 ~ 5
The reproduced signal regenerated by _-5 is sent to the regenerative amplifier 7 _-1 ~
7 _-5 amplified by recording amplifier 1 of playback device 3
1 _-1 to 11 _-5 are supplied simultaneously.

The switch means 10 _-1 to 10 _-5 of the recording device 3 are synchronized with the switch means 6 _-1 to 6 _-5 of the playback device 2, and the recording amplifiers 11 _-1 to 11 _-5 are synchronized with the switch means 6 of the playback device 2.
_-1 to _6-5 are connected to magnetic heads _9-1 to _9-5 . Further, since the rotation of the rotary head drum 8 is synchronized with the rotation of the rotary head drum 4, the magnetic heads 9 _-1 to 9 _-5 simultaneously dub and record the reproduction signals as five video tracks on the magnetic tape 13. Since the running speed of the magnetic tape 13 and the diameter of the rotary head drum 8 in the recording device 3 are the same as those in the reproducing device 2, the video tracks recorded by dubbing by the magnetic heads _9-1 to _9-5 are master tracks. It has the same shape as the video track recorded on the magnetic tape 12. Subsequently, when the rotary head drum 4 of the playback device 2 rotates 180 degrees, the magnetic heads _5-6 to _5-10 on the other side record the next five video tracks _A6 on the master magnetic tape 12.
~ _A10 (shown in FIG. 3) are scanned simultaneously to reproduce the recorded signal. At this time, the switch means 6 _-1 to 6 _-5 ,
10 _-1 to 10 _-5 are magnetic heads 5 _-6 to 5 _-10 , 9 _-6 to
The connection is switched to _9-10 , and the above reproduction signals are simultaneously dubbed and recorded on the magnetic tape 13 as five video tracks. Thereafter, the same process is repeated and the information recorded on the master magnetic tape 12 is dubbed onto the magnetic tape 13.

By simultaneously reproducing a plurality of (for example, five) video tracks recorded on the master magnetic tape 12 as described above and dubbing and recording the reproduced signals on another magnetic tape 13 at the same time, the rotary head drums 4 and 8 are The number of video tracks that are played back or recorded during rotation becomes large (five times as many in this embodiment), and the number of magnetic tapes 12,
13 scanning speed can be increased. Note that when setting the diameter dimensions of the above-described rotary head drums 4 and 8, the number of magnetic heads (the number of video tracks formed during one rotation of the rotary head drums 4 and 8) is added to the parameters as track pitch P and calculated. magnetic tape 12, 13
The traveling speed of the magnetic head is set to an appropriate speed corresponding to the number of magnetic heads. It goes without saying that the above-described dubbing method can be applied not only to video tape recorders but also to various devices such as digital audio tape recorders using rotating heads.

Effects of the Invention As described above, according to the dubbing method of the present invention, a plurality of magnetic heads of a playback device simultaneously play back a plurality of video tracks of a master magnetic tape, and a recording signal supplied with a playback signal from the playback device is reproduced. By configuring a plurality of magnetic heads of the device to simultaneously dub and record the playback signals onto other magnetic tapes, a large number of video tracks can be played back or dubbing recorded during one rotation of a pair of rotary heads. Therefore, the running speed of the magnetic tape can be correspondingly increased, and the deviation between the magnetic head and the prescribed video track caused by increasing the running speed of the magnetic tape can be reduced by the diameter of the rotating head drum. The time required for dubbing recording can be shortened because it can be corrected by selecting appropriately.In addition, since the time required for dubbing recording is shortened, the magnetic tape can be dubbed and recorded within a predetermined time. Since the number of dubbing video tape recorders can be increased, there is no need to prepare a large number of video tape recorders for dubbing as in the past, and the equipment cost can be reduced.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing a dubbing device using an embodiment of the dubbing method of a rotary head type tape recorder according to the present invention, and FIG. 2 explains the arrangement positional relationship of a plurality of magnetic heads with respect to the rotary head drum. FIG. 3 is a diagram for explaining the locus scanned by the magnetic head disposed on the rotary head drum during reproduction or dubbing recording. 1...Dubbing device, 2...Playback device, 3...
Recording device, 4, 8... Rotating head drum, 5 _-1 ~
_5-10 , _9-1 to _9-10 ...magnetic head, _6-1 to _6-5 ,
10 _-1 to 10 _-5 ... switch means, 7 _-1 to 7 _-5 ...
...Reproducing amplifier, 11 _-1 to 11 _-5 ... Recording amplifier,
12,13...magnetic tape.

Claims (1)

[Claims] 1. A reproducing device and a recording device are each provided with a plurality of pairs of rotating heads, and the plurality of magnetic heads of the reproducing device form a predetermined track to simultaneously reproduce a plurality of video tracks magnetically recorded on a magnetic tape, A dubbing system for a rotary head type tape recorder, characterized in that a plurality of magnetic heads of the recording device supplied with a reproduction signal from the reproduction device simultaneously dub and record the reproduction signal onto another magnetic tape. .