JPS6199942A - High speed dubbing system of vtr - Google Patents

Abstract

PURPOSE:To keep a relative speed constant by making the second running speed vector different from the first running speed vector in the course of stop of the first and the second magnetic tapes at a speed of (n) times, running the first and the second magnetic tapes at a speed of (n) times, and executing a high speed dubbing. CONSTITUTION:When magnetic tapes 1, 11 run in the direction Q, rotary magnetic heads 5a,...5d, 10a,...10d rotate in the direction R centering around a shaft 14. Also, when the magnetic tape 1 runs by a vector Vt1, a prescribed information signal is recorded in the magnetic tape 1. In case a high speed dubbing is executed to the magnetic tape 11 from the magnetic tape 1 by running the magnetic tapes 1, 11 at a speed of (n) times, since an information signal is recorded in advance in the magnetic tape 1 by a relative speed vector, the relative speed vector of the magnetic tapes 1, 11 must not be varied. Accordingly, the second running speed vector of the rotary magnetic heads 10a,... in the course of stop of the magnetic tapes 1, 11 is made different from the first running speed vector, also the rotary magnetic heads of the number corresponding to the speed of (n) times are provided, and a high speed dubbing is executed by running the magnetic tape at a speed of (n) times.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to a dubbing method for a VTR dedicated to dubbing, in which information signals are read from a magnetic tape on which information signals are recorded and recorded on another magnetic tape. .

(B) Conventional technology Conventionally, a dubbing device for recording an information signal recorded on a magnetic tape onto another magnetic tape has been used.
"rVTR high speed dubbing device shown in No. 134416"
There is. In this device, multiple video heads are attached to the cylinder.

Video heads were arranged in multiple rows in the axial direction of the cylinder, and a master tape was played back and dubbed onto a slave tape using the number of running systems corresponding to the multiple rows.

(c) Problems to be Solved by the Invention However, since a plurality of video heads are provided, when the magnetic tape is run at normal speed.

It is written that dubbing is possible at twice the speed (F &> 1), but if the number of video heads used when recording to the master tape and the number of video heads when dubbing are different, the master tape will be played back at the same speed. Even if you double the rotational speed of the video head and dub, the relative speed between the magnetic tape and the video head will be different, so it is difficult to reliably play the master tape. It had become impossible to do so.

Furthermore, by increasing the rotational speed of the video head to correspond to the running speed of the magnetic tape, it is possible to dub a given noise signal in one hour. The relative speed of the video head relative to the running speed has increased, and the frequencies handled have become extremely high, making most of the existing circuits used in dubbing equipment unusable and making it impossible to perform high-speed dubbing. There were some problems.

B) Means for Solving the Problems The present invention has been made to solve the above problems, and it reads information signals from a first magnetic tape on which the information signals are recorded and transfers them to a second magnetic tape. VTR to record on
In the dubbing method.

a rotational speed of a rotating magnetic head provided on the reproduction side and recording side of the VTR to which the first and second magnetic tapes are mounted, respectively, and that diagonally scans the first and second magnetic tapes wound around a cylinder; When the relative speeds to the running speeds of the first and wE2 magnetic tapes are made equal, and the first and second magnetic tapes run at a speed 93 times the normal running speed (3>1).

The normal running speed vector of the first and wIJ2 magnetic tapes, and the vector of the rotating magnetic head when the rotating magnetic head obliquely scans the first and second magnetic tapes that are stopped at the normal running speed. the first and second magnetic tapes obtained from a vector sum with one running speed vector;
In order to keep the relative velocity vector of the rotary magnetic head constant, the second traveling velocity vector of the rotary magnetic head while the first and second magnetic tapes are stopped is changed to the first velocity vector while the first and second magnetic tapes are stopped. different from the running speed vector and providing the number of rotating magnetic heads for the double speed;
This is a high-speed dubbing method for VTRs in which high-speed dubbing is performed by running the first and second magnetic tapes mounted on the VTRs on the reproduction side and the recording side at double speeds.

(e) Effect In a high-speed dubbing method for a VTR according to the present invention.

The first magnetic tape on which information signals are recorded is transferred to a VTR on the playback side.
Then, dubbing is performed by attaching the second magnetic tapes on which the information signals are to be dubbed to the VTR on the recording side. The vector sum of the running speed vector when the rotating magnetic head scans the second magnetic tape, that is, the relative velocity vector, is changed to the normal running speed of the first and second magnetic tapes (3>1). The number of rotating magnetic heads is set to keep the speed constant even when the speed is multiplied.

From this, the first and second magnetic tapes are run at n times the speed, and the information signal recorded on the first magnetic tape in time α is dubbed in 7 hours without generating noise bars.

(f) Example The details of the present invention will be specifically explained with reference to illustrated embodiments.

Fig. 1 is a block diagram showing a high-speed dubbing method for a VTR according to the present invention, and Fig. 2 shows an embodiment of a device using the high-speed dubbing method for a VTR according to the present invention, in which a magnetic tape is wound around a cylinder. A perspective view, FIG. 3 is a VT of the present invention.
A vector diagram showing the relative speed of the rotating magnetic head with respect to the running speed of the magnetic tape in the R high-speed dubbing method,
FIG. 4 shows the high-speed dubbing method of the VTR of the present invention.
5 is a diagram showing the number of rotating magnetic heads and their scanning states; FIG.

To explain the figure numbers and configurations of Figures 1 and 2,
(1) is a magnetic tape as a first magnetic tape on which a predetermined information signal is recorded, (2) is a control unit that controls the operation of the entire device, and (3) is a magnetic tape that is a first magnetic tape on which a predetermined information signal is recorded. A control head on the playback side receives a control output and detects a control signal from the magnetic tape (1).

(4) is a rotating magnetic heald (5a) (5b) (!M) on the playback side which operates in a plurality of circuits in response to the control signal output and corresponds to the running speed of the magnetic tape (1). ... (5d) head switching circuit that switches the scanning output;
(6) is the rotating magnetic head (5a) (5b) (5c)
...(5d) An amplifier for amplifying the video signal read out from the magnetic tape (1) by the IC, and (7) a waveform for performing predetermined waveform shaping processing on the video signal after being amplified by the amplifier (6). a shaping circuit (8) is the waveform shaping circuit (7);
), an amplifier that amplifies the video signal after waveform shaping by (9
) is a recording-side rotary magnetic head (
a head switching circuit that switches the scanning output of 10aX10b3 (IOC) (10d) and records the video signal amplified by the amplifier (8) on the magnetic tape αDK;
z receives the control output from the control unit (2) and controls the rotating magnetic head (10a) (10b) (IOC) (1
A control head on the recording side that records a control signal corresponding to the switching of 0d) on the magnetic tape α1)K, Q
l is a cylinder that rotates around axis α4, US is a tape guide, (16aX16b) is a loading post,
(17a) and (17b) are inclined poles.

Note that the rotating magnetic head (5M) (5b) (5
G')--(5d) and rotating magnetic head (10a) (1
0b)(10c)...(10d) are equal in number, and the magnetic tape shown by the two-dot chain line in FIG.
) (1m) and one rotation magnetic head is a rotating magnetic head (5a) (5b) (5c) = (5d)
, (10a) (10b) (10c) - (10d)
, one of the following.

FIG. 1 shows a high-speed dubbing system for a VTR according to the present invention.

This will be explained using FIGS. 2, 3, and 4.

First, to explain the vector diagram shown in Fig. 3, vector
'Xejh l IZJ9 Magnetic Tape (1) Shows the running speed vector at 1x, 2x, 3x, . . . le times the speed of αB.

V, n=le VH It is.

Generally, as shown in Figure 2, magnetic tape +1) (1m) is
When traveling in the direction, the magnetic head (5a) (5b) (
5c)・(5d), (10a)(10b)(IOC
)! -(10d) rotates around the axis α field in the direction of the center KR force.

Furthermore, it is assumed that a predetermined information signal is recorded on the magnetic tape (1) by running the magnetic tape (1) at a normal speed of 1x, that is, at the vector Vts. From this, when the vector MU of the magnetic tape (1) is used as a reference, the relative velocity vector of the rotating magnetic head when a predetermined information signal is recorded is Vhs. Also, the relative velocity vector when the magnetic tape (1) is stopped is ■. VhO is obtained from the vector sum of and Vhs.

When performing high-speed dubbing from magnetic tape (1) to magnetic tape (1υ) by running magnetic tape (1) αυ twice as fast as described above, the magnetic tape (1) K is the relative velocity vector v
This is because the information signal is recorded by hl.

Even if the running speed of the magnetic tape (1) Ql) changes, the relative speed vector vht must not change.

From this, the running speed vector V of the magnetic tape (1) αυ,
,.

Magnetic tape (1) corresponding to V, ...Vt, (
11) Rotating magnetic head (5a) (5b) while stopped
) (5c) ・, ...<5d) .

'(10a), (10b), (10c) and (10d), respectively, and the traveling speed vector is 1. ÷t1
．． ...÷t, and the relative velocity vector v[1].
(t-n).

Here, using mathematical formulas, the rotating magnetic head (5a) (5b) (
5c) - (5d), (10a) (10b) (10c)
...Let's find the relative velocity of (10d). Relative velocity vectors Vht, Vho.

Let the angle formed by ÷h(sss) be θ3. θ. , θ1−. ．．
If so.

The absolute value of the relative velocity vector vho, that is, the relative velocity vho
Hato becomes. From this, relative velocity vector Vh (t-+s)
The absolute value of , that is, the relative velocity vh o-rb) is Vh(s
4)=Vb”t+Vtrc+2VtsVhtcosi
9. −=■. Also, θ becomes -11.

Furthermore, when the running speed of the magnetic tapes (1) and (11) is taken as a reference, the total track width W of the magnetic tape (1) 9 is proportional to and constant, and the track length is also constant. ) (5b) (5c) - (5d), (10a)
It is proportional to the relative velocity of (10b) (10e)...(10d). From this, when the magnetic tapes (1) and (11) run at high speed twice as fast, the rotating magnetic heads (5a) (5b) (5c) ... (5
d) , (10a) (10b) (10c) ...(
The track length L1-1 of the track generated by scanning the magnetic tapes (1) and (1 m) respectively by the magnetic tapes (10d) and (10d) is as follows. Furthermore, the effective winding of the magnetic tape (1) αB when viewed from the top of the cylinder (13) is such that the angle is θ1 and the magnetic tape (1
) (If the diameter of the cylinder 83 when the LD running speed is double the speed is φ, -1, then the track length, -1 is also expressed, and to keep the track length L1-n constant, θ and φ , -1 must be inversely proportional.

Calculating φ and -5 from the above equations ■ and 0.

becomes.

Next, the rotating magnetic head (5a) (5b) (5c) is based on the running speed of the magnetic tape (1) (11) at double speed.
”・(5d).

(10a) (10b) (IOC) ・If the number of rotations per unit time of (10d) is R1-%, then R1-hk
Using @■ and 0 formula.

becomes.

Next is the number of rotating magnetic heads.

If the running speed of the magnetic tape (1) aυ is 1x speed, that is, the normal speed, the number of rotating magnetic heads is 2,
The angle θr of the effective winding on the cylinder α is π(rad
). Here, when the magnetic tape (1) (111) runs at a high speed that is twice as fast as R, if the number of magnetic heads per revolution is two, the magnetic head per revolution scans one track in the rack. It becomes only Therefore, the number of rotating magnetic heads ``xs 't'L 111''2
3 °°°°°°°°°゛°゛°°°°°°°°°°
°°°"−----＊＊＊m-1n■.In addition, r&Ml in the formula It is also possible to increase or decrease the number of rotating magnetic heads.

Next, the effective winding is the relationship between the angle θ and the number of rotating magnetic heads ζ. 1) When αD travels at a high speed of 9 times the traveling speed, the effective winding is that a predetermined number of rotating magnetic heads must be arranged within an angle 01 with a pitch angle of θ, and from this, θ, = θ. , (rad) ・・・・・・・・・・・・
・・・・・・・・・・・・・・・・・・・・・■. on the other hand.

From equations (1) and 0, the relationship between the number of rotating magnetic heads - and the effective winding angle θ is as follows. However, normally every track (3. is an even number because the azimuth of the rotating magnetic head is changed, and the effective winding per track is an angle θ).

must not exceed 2π (rad).

Next, the drawing shown in FIG. 4 will be explained. This is done by running the magnetic tapes (1) and (11) at a high speed of 4 times the running speed, and using equation 0, (a) becomes n, = 8 (pieces), θ
, = 180°, (b) is n, = 6 (pieces), θ, =
24 o.

This is an example showing the case of Furthermore, the vertical axis θr (A~P
) indicates the pitch angle, and the rotating magnetic head will be written with a number.

First, in case (a), the pitch angle of the eight rotating magnetic heads,
is 451, and the diagonal lines in the one-rotation magnetic head indicate azimuths, and these azimuths are alternately different so that recording can be performed without guard panning.

The rotating magnetic heads 1, 2, 3.4 are connected to the magnetic tape (1
) When scanning aυ, the rotating magnetic heads 5, 6, 7°8 do not scan the magnetic tape (1) fil), and the rotating magnetic heads 5. 6,7. 8 scans the magnetic tape (1) αB, the rotating magnetic heads 1, 2, 3, and 4 scan the magnetic tape (1) αB.
1) If the number of the rotating magnetic head that does not scan αB and scans the magnetic tape (11 αB) shifts by a predetermined number forward or backward, the number of the rotary magnetic head that does not scan the magnetic tape (1) or (11) also shifts by a predetermined number forward or backward. It shifts.

Next, in case (b), the pitch angle of the six rotating magnetic heads is 60", and the azimuths of the one-turn magnetic heads are alternately different, so wiring can be done without guard panning. Then, the rotating magnetic heads 1 and 2 .3 and 4 are magnetic tapes (1) (11
), the rotating magnetic head 5゜6 scans the magnetic tape (
1) If the number of the rotating magnetic head that does not scan (11) and scans the magnetic tape (11 (11)) shifts forward or backward by a predetermined number, the number of the rotating magnetic head that does not scan the magnetic tape (1) (11) will also change. , and are also shifted by a predetermined number of pieces forward and backward.

In this way, by configuring the device defined by the formula with the above-mentioned numbers, as shown in FIG. 1, the magnetic tape (1 ) (11) is run at high speed at the same speed as the rotating magnetic spatula)" (5a)
) (empty b) (5c) ... (5d) , (10a)
(10b) (10C)...(10d) High-speed dubbing is performed using the following.

Furthermore, there is no problem in using the reproducing side and recording side VTRs as mutually independent devices.

(g) Effects of the invention According to the VTR high-speed dubbing device of the present invention.

Even if the magnetic tapes attached to the playback and recording sides of a VTR are run at high speeds that are double the normal recording/playback speed, the relative speed of the rotating magnetic head with respect to the running speed of the magnetic tape remains constant. From this, it is possible to dub an information signal recorded for α hours in one hour without generating noise bars.Furthermore, the number of rotating magnetic heads used can be adjusted so that the effective winding of the magnetic tape around the cylinder is Consider 1. , which can be set to a minimum, which provides advantages such as cost reduction.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a dubbing device for a VTR according to the present invention. FIG. 1wcZ is a perspective view showing an example of a state in which a magnetic tape is wound around a cylinder in a device using a high-speed dubbing system for a VTR according to the present invention. FIG. 3 shows the high-speed dubbing method of the VTR of the present invention.
FIG. 4 is a vector diagram showing the relative speed of the rotating magnetic head with respect to the running speed of the magnetic tape. FIG. 4 is a drawing showing the number of single rotating magnetic heads and their scanning state in the high-speed dubbing system of the VTR of the present invention. Explanation of main drawing numbers (1) αn-...magnetic tape, (5a) (5b)
(5c)F...(5d). (10a) (10b) (10c) −(10d) =・
Rotating magnetic head. a3... cylinder. Applicant Sanyo Electric Co., Ltd. and one other agent Patent attorney Shizuo Sano No. 2g Figure 3 Figure 4

Claims (1)

[Claims] (1) A VT that reads information signals from a first magnetic tape on which the information signals are recorded and records them on a second magnetic tape.
In the R dubbing method, rotation is provided on the reproduction side and the recording side of a VTR to which the first and second magnetic tapes are mounted, respectively, and diagonally scans the first and second magnetic tapes wound around a cylinder. The relative speed between the rotational speed of the magnetic head and the running speed of the first and second magnetic tapes is made equal, and the first and second magnetic tapes are set at n times the normal running speed (n>1). A normal running speed vector of the first and second magnetic tapes when running, and a vector of the first and second magnetic tapes when the rotating magnetic head obliquely scans the first and second magnetic tapes while they are stopped at the normal running speed. In order to maintain constant the relative velocity vector of the first and second magnetic tapes and the rotating magnetic head obtained from the vector sum with the first running velocity vector of the rotating magnetic head, and a second running speed vector of the rotating magnetic head while the second magnetic tape is stopped is different from the first running speed vector, and a number of rotating magnetic heads is provided for the n-times speed, and This is a high-speed dubbing method for VTRs, which is characterized in that high-speed dubbing is performed by running the magnetic tape of No. 2 at n times the speed.