JPS6022705A - Signal recorder - Google Patents

Abstract

PURPOSE:To record a tape pattern equal to that of a two-head type VTR and at the same time to attain miniaturization of a rotor by setting the number of recording heads attached to the rotor at >=4 even numbers. CONSTITUTION:Six heads are attached to a rotor 1 with equal angular intervals, and heads HA and HB have gaps of azimuth angles theta and -theta respectively. Each head has the track width equal to a track pitch, and different azimuth angles are set between adjacent heads respectively. A magnetic tape 2 touches the rotor 1 within a range of angles alpha and beta respectively for overlap recording with 300 deg. effective winding angle. The rotor 1 is revolved by F(n-1)/n number of revolutions per second (n: number of heads). The video signal is supplied selectively to either one of heads. When a head HA1, for example, is set near a guide pole 3, the video head is supplied only to this head continuously until the head HA1 comes close to a guide pole 4. In this case, the supply of the signal is started to a head HB1.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a signal recording device, and in particular, an even number of 4 or more female Cu heads installed on a rotating body at equal angular intervals improves the current state of the art. Two-head magnetic recording/reproducing device (VTR)
The same tape pattern is recorded on the magnetic tape.
Related to equipment.

Prior art and its problems In a conventional two-head helical scan type VTR using an azimuth recording/reproducing method, two heads are placed opposite each other on a rotating body, and the azimuth angles are opposite to each other with respect to the track width direction. J
: Information signals such as video signals are recorded on magnetic tape (as is well known).

However, in the above-mentioned VTR, the valid angle of the magnetic tape with respect to the rotating body is 180°, and even if a slight overlap recording is added, it can only be used for about half a turn of the rotating body. Since it was not used for recording with a head of -, a rotating body with a large diameter had to be used in order to obtain the required relative speed between the tape and head (by the way, the relative speed between the tape and head was 5. 8017 S (
7, the diameter of the rotating body is 62vn.

On the other hand, the portaple type V T is desired to be smaller and lighter.
In R, the size of the rotating body has such a great influence that it affects the amount of equipment downtime.

However, when standards such as tape patterns are established, the diameter of this rotating body becomes constant, and therefore even porta-pull type VTRs must be equipped with a rotating body of the above-mentioned large diameter.
This has placed restrictions on miniaturization and weight reduction of the device.

SUMMARY OF THE INVENTION An object of the present invention is to provide a signal recording device that solves the above problems by increasing the number of recording heads attached to a rotating body to an even number of four or more.

Means for Solving the Problems The present invention provides n pieces having one of two different azimuth angles and one herb width approximately equal to one track pitch (where 1, n more than i
Heads (number) are arranged at equal angular intervals on a rotating body, and adjacent heads on the rotating body are arranged with different azimuth angles, and the field frequency F (1
-1z) When recording video No. 13, the rotating body was rotated every second ((n
On a magnetic data j that is rotated at a rotation speed of l)/II)・F and is made to travel while being wound around a rotating body at a right-handed winding angle f'' that satisfies the formula 360°・(n-1)/n. Then, the above n heads are sequentially and cyclically switched at intervals equal to I+3 during the effective winding angle rotation period.
This system was developed to record signals by sequentially forming racks of rack pitches, and one embodiment thereof will be described below with reference to the drawings.

Embodiment FIG. 1 shows an embodiment of the relationship between the head arrangement and deep winding of the device of the present invention, and FIG. 2 is a perspective view of an embodiment of the head rotation mechanism of the device of the present invention. In the figure, the same components are designated by the same reference numerals.

In both figures, a rotating body 1 such as a rotating drum or a disk plate 1 rotatably disposed between upper and lower solid gamma drums is shown.
Above, six heads 1-IAI, I-IB+.

IA2. He2. IA3 and t-1e3 are fixed at equal angular intervals of 60 degrees. Head HA I.

1''A2 and 1-IA3 each have a gap with an azimuth angle inclined by θ (for example, 6°) with respect to the track width direction, and the head Hot.

1'' 82 and 1-In2 each have a gap with an azimuth angle inclined by -θ (for example, -6°) with respect to the track width direction. In addition, six heads 1] A1 to 1-IA
3, Hs + ~ 1'' B3 each has a track width equal to one track pitch, and each 40 adjacent heads have different azimuth angles.
As shown in the figure and FIG. 2, it is arranged on the rotating body 1.

This rotary body 1 is attached to the rotating body 1 by guide poles 3 and 4, so that an angle of just over 300° is formed by adding angles α° and β° for A-burlap recording to the effective winding angle of 300°, respectively, as shown in FIG. The magnetic tape 2 is spliced and wound over the circumference of e.

The magnetic tape 2 passes in front of the A-dio control head 5 from the guide pole 4 and is held between a capstan 6 and a binding roller 7, and is moved in the direction of arrow X by the rotation of the capstan 6. .

In addition, the center of the rotating body 1 is shown in FIG.
The disks 10, 11 and '12 are fixed to the rotational end of the motor 8 at the rotation end 9, and the disks 10, 11 and '12 are coaxially attached with their central portions penetrating and fixed to the rotating shaft 9.

On the disc 10, a magnet 13a magnetized to N pole and a magnet 13b magnetized to 34 are mounted facing each other.

1" B2 is mounted at a position parallel to the axial direction of the rotating shaft 9, and on the disk 11 there are magnets 14a magnetized to the north pole and magnets 14a magnetized to the south pole. The magnetized magnets h 14 b are connected to the heads He, respectively.
+, 1-IA It is attached corresponding to the attachment position of 3. Further, in a direction parallel to the axial direction of the rotating shaft 9, a magnet 15a magnetized to the N pole is fixedly attached to a position on the disk 12 corresponding to the head HAz position (=1 position), and similarly the head l -183 Corresponding to the mounting position, a magnet (not shown) having four S poles is mounted and fixed at a position on the disc 12.

Rotating body 12 discs 10-12 and heads HAI-1-IA
3, 1-1s +~H [+3 is the magnetic tape 2, respectively
([When recording a video signal with field frequency F(1-(z)), the motor 8
・It is rotated integrally at a rotation speed of F. Here, n is the number of heads. In this embodiment, n is 6, and assuming that a video signal with a field frequency of Gof-1z is to be recorded, the number of revolutions of the motor 8 is 50 from the above equation.
rps, and therefore the rotating body 1, circle'! The rotation speed of A10 to A12 etc. is also 50 rps.

The rotating body 1 is rotated counterclockwise in FIG.

Due to the above rotation, the magnets 1-13a on the disk 10,
13tl is yen! Same as 10? The rotation detection head 16 passes in front of the gap of the rotation detection head 16 (not shown in FIG. 2) provided at the 3-point position at a constant period, and as a result, as shown in FIG. passes in front and outputs a positive pulse when it is an IC, and when magnets 1-i3b passes in front, it outputs a negative pulse.

Similarly, the rotation detection pulse as shown in FIG. The rotation detection head 18 shown in Fig. 3 (C
) A rotation detection pulse as shown in FIG.

The above rotation detection heads 16 to 18 (well, head HA
I~FIA3. H131 to H11B3 are positioned so as to output rotation detection pulses when recording of the overlap recording angle α° on the guide pole 3 side shown in FIG. 1 is completed. Therefore, the rotation detection heads 16 to 18 are provided on the same line parallel to the axial direction of the rotating shaft 9 of the motor 8.

Next, head HAI~1-IA3. IBI~l-1B3
The video signal recording operation will be explained below. For example 7
Eel frequency 601-1z (or 5ri, 94t
-1z) is converted into a signal format suitable for magnetic recording and reproduction, and then the switch circuit converts the video signal to head 1'' A1.
~HA 3 , 1-Is I~1'' is selectively supplied to any one of the heads below B3. Also, the head l-l
Assuming that Al comes near the guide pole 3 shown in FIG. The magnetic tape continues to be supplied until A1 comes close to the guide pole 4 and is no longer in contact with the magnetic tape 2.

Head 1- (When head HA+ rotates 60 degrees after recording of one field of the recording video signal is started by A+, head 1" 83, which is provided at a trailing position with respect to the rotational direction, starts recording one field of the recording video signal. started contacting head 1.
When A1 rotates a total of 120 degrees, head 1-IA3 begins to contact magnetic tape 2, and further head 1''A1 rotates at word 180.
At the point when the head HBz rotates to form a trunk portion of about 315 degrees long for one video track, the head HBz starts to come into contact with the magnetic tape 2, and the head HA+ rotates a total of 240 degrees to form one video track. At the point when a track portion having a length of about 415 is formed, the head 1''A2 starts to come into contact with the magnetic tape 2, and the head HA+ becomes ff+30.
The head 11B1 begins to come into contact with the magnetic tape 2 at the time when it has rotated 0" and has recorded substantially all of the first through racks of one bidet.

Here, since the tape running speed is selected so that the magnetic tape 2 is run by one track pitch when the head HAI rotates 300', the head 1-IAI
The above-mentioned heads t-le 3, HA contact the magnetic tape 2 sequentially during the formation of a video 1-rack recording of a tree.
3, 1-le2, and HA2 overlap and scan a part of the video 1 rack that is being recorded by the head 1-IAI. However, these heads 1-18
Since recording video signals are not supplied to 3, 1-IA 3 , 1-+82 and 1-IA2, no video track is recorded or formed by these heads. When the head HA+ has rotated approximately 300 degrees and recorded almost the entire video track of one tree, the video signal for recording of the next field is transferred to the head 11B1 at the spatula 11B1 which starts to come into contact with the magnetic tape 2. From then on, the head Ha+
The recording video signal continues to be supplied until it rotates about 300' and comes out of contact with vA-Dave 2. As a result, one video track on which a little more than one field worth of video signals is recorded by the head 1-Ie+ is formed at a position adjacent to the video track recorded and formed by the head HAI 1w. Here, since the track width of each of the heads I''AI~l-I A 3°He+~l-183 is equal to one track pitch, there is no overlapping recording on the already recorded and secondary racks. New bidets are recorded.

During the period when head 1''B1 is recording and forming one video track, head 1-(A+, 1-IB
3'.

HA3 and I-IB2 perform single and multiple scans on a part of the racks, respectively, but since recording video signals are not supplied to these heads, a libide 711-rack is formed by these heads. Never. Above head H
Immediately before the o+ finishes recording one video track, the head HA2 begins to come into contact with the magnetic tape 2.
At this point, the video signal of the next field is transmitted to head l-,
Begins to be supplied to IA2.

As a result, J: Rivide 1-rack is recorded and formed on head 1''^2 without a guard band at a position adjacent to the video 1-rack recorded and formed by head 11B1. Thereafter, the same operation as above is repeated.

In this way, head 1''8+, t-1Bt.

HΔ21 +−IB 21FIA3 and [''B3,
Figure 3 (D), (E), (F), (G), (H) and (
, 1), the video signal is switched and inputted based on the rotation detection pulses shown in FIGS. ” A1 → To1s+ → HA 2
→ HO2 → To1 8 3 → l-1B3 → To I
A1→...Video tracks are sequentially formed in which video (Z! signals) are recorded for one field plus an overlap recording period.

Note that in FIG. 1, the video signals of the fields before and after one field are recorded in an overlapping manner during the α° rotation period before the start of signal recording of one field period and the β° rotation period after the end of recording. , Figures 3(D)-(I)
It is clear from this. As is well known, this makes it possible to prevent the reproduced signal from being cut off even if the head switching point during reproduction changes somewhat.

In addition, the disks 10, 11.12 and the rotation detection head 16.17
．． Reference numeral 18 denotes, for example, the disc 10 and the rotation detection head 1G, and other rotation detection pulses obtained by the rotation detection head 17 and 18 are electrically generated by a Y extension circuit, and these are used as head switching signals. There may be.

Figure 4 shows head 1-(81-I(A 3 , 1-IB+
~14B3 etc. show tape patterns recorded and formed, bidet 1 ~ rack'l+'2+13. ”+ts,t
s, . . . head 1-1A+, tIs+, 1-
IA2.

The video tracks recorded and formed by Hoz, HA3, HO3, . . . are shown. In addition, pulses as shown in FIG. 13 (J), which are generated by dividing the vertical synchronization signal in the recorded video signal by half, etc., are generated by the control head in the head 5 shown in FIG. 1 to the size shown in FIG. control track 1
Recorded on 9th. Bidet 1st to rack t+, t2. t3.
t4. ts,, t6°... are shown in Figure 3 (1<).
1st field F1, 2nd field F2, 3rd field F3, 4th field of the video signal for recording]
1st field F4. 5th field F5, 6th field F6. ... are recorded sequentially without guard bands.

That is, the 1' tape pattern shown in FIG.
+ to 1-1Δ3, 1-1e+ to l-183, it is possible to record a tape pattern that is completely similar to the above-mentioned two-head VTR.

Here, the diameter of the rotary body in which n heads are taken at equal angular intervals to form tape per-recording shown in FIG. The relationship with d is expressed by the formula D=116/(2(n-1>)' (1). In this example, since n=(3), the rotating body 1
The diameter of
315 times. Therefore, according to this embodiment, a tape pattern that is completely tape compatible with the current 2-head VTR as shown in FIG. can do.

Figure 5 shows the relationship between the diameter and the number of heads, n.
As is clear from the figure, as the number of heads n (n is an even number of 4 or more) increases, the diameter approaches half of the diameter d of the head mounting rotating body of the current two-head VTR.

In addition, as mentioned above, the field frequency of the video signal is F
(Hz), and the number of heads is 0 and J゛, then the rotation speed N (
rps) is expressed by the formula N=F(n-1)/n (rl)s> (2), so as shown in Figure 6, as the number of heads increases from 11 to 1, the rotation speed N approaches F. To go.

Here, since the flywheel effect of a rotating body with a diameter is proportional to the square of the rotation speed N, the second moment of inertia of the rotating body 1 is In this embodiment, the rotational speed is 1.67 times that of the current two-head VTR, so it is 0.36. This leads to a reduction in the overlap of the rotating body 1, and the same moment of inertia l as that of the rotating body to which the head of a 2-head VTR is mounted is caused on the rotating body 1.
When a - rotational φλ body is used, the flywheel effect is more than doubled, and as a result, jitter induced by uneven rotation of the rotating body 1 is reduced.

In addition, by using the apparatus configured as shown in FIGS. 1 and 2,
It is also possible to reproduce the tape parkon magnetic tape 2 shown in FIG.

Application Examples Note that the present invention is not limited to the above embodiments, and the number n of heads may be 4 or an even number of 8 or more. In that case, the diameter of the rotating body for mounting the head is expressed by equation (1), the number of rotations N is expressed by equation (2), and the effective tape winding angle is ((n-1)'/r+) ・It is expressed in 360°. Note that, as a matter of course, the running speed of the tape is the same as that of the current two-head VTR, regardless of the number of heads n.

Effects As described above, according to the present invention, there are n tracks whose width is approximately equal to 11 track widths (however, 0 is an even number of 4 or more).
Since recording is performed using a head of 1, it is possible to prevent the recording of the next video track by overlapping a part of the video track that was recorded immediately before, and this makes it possible to prevent the recording of the next video track from overlapping a part of the video track that was recorded immediately before. It is possible to prevent the phenomenon in which a long low-frequency conversion carrier color signal remains as a residual signal without being completely erased and is reproduced as crosstalk during playback, degrading the image quality.
A rotary body is rotated every second ((11-1)/n)・F onto a magnetic tape wound at an angle of 4(), which is a valid ticket of n−i)/n.
(where F is the field frequency of the recorded video), the head is rotated at a rotational speed of By means of a rotating body with a diameter smaller than the
The same tape pattern as that of the current two-head VTR can be recorded, and the rotating body can be made smaller in diameter, making the device more compact.

It is possible to reduce the weight, and if a rotating body with the same moment of inertia as the rotating body for mounting the head of a 2-head Vl-R is used, the flywheel effect will be more than twice as loud, which is caused by uneven rotation. 1) It has a length that can reduce jitter.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of the head arrangement and tape winding relationship of the device of the present invention, and FIG. 2 is a diagram showing the head rotating machine 4 of the device of the present invention.
7'3 Part A'' A recent example is taken from a perspective view, Figures 3 (A) to (] <) are time charts for explaining the operation of this unexploded device, and Figure 4 is a time chart recorded by the unexploded device. A diagram showing the formed tape pattern, Figure 5 is a partial diagram showing the relationship between the diameter of the rotating body and the number of heads, and Figure 6 is a diagram showing the relationship between the rotation speed of the rotating body and the number of heads. . DESCRIPTION OF SYMBOLS 1...Rotating body, 2...Magnetic tape, 5...A-dio control head, 6...Ki A7 bustan,
7... Pinch roller, 8... Motor, 9... Rotating shaft, 10 to 12... Disc, 16 to 18... Rotation detection head, 1-IAI to l-lA3... First Heads with an azimuth angle of H81 to HB3...heads with a second azimuth angle. Fan 3 figure m - the time

Claims (1)

[Claims] n heads (where n is an even number of 4 or more) having one of two different azimuth angles and a track width approximately equal to one track pitch are placed on a rotating body at equal angular intervals. At the same time, adjacent heads on the rotating body are arranged so that they have different azimuth angles, and when recording a video signal of field frequency F (Iz), the rotating body is rotated every second (( n-1)/n)・
Rotate at a rotation speed of F and give the rotating body 360° (
On a magnetic tape that is wound and run while being wound at an effective winding angle that satisfies the formula n-1>/n, the n pieces are sequentially and cyclically switched at intervals approximately equal to the effective winding angle rotation period. A signal recording apparatus characterized in that signals are recorded by sequentially forming tracks of one track pitch with a head.