JPH01124181A - Rotary head type recorder - Google Patents

Abstract

PURPOSE:To monitor recording so that a recording head can be prevented from missing recording due to an accident such as jam by holding a head tracing a recording medium at a reproducing state other than a recording head during the recording of signals. CONSTITUTION:In a recording mode, heads 1-4 other than a recording head 1, 2, 3 or 4 are constituted so as to trace the recording medium 6 simultaneously with the recording head to reproduce record. Since the heads other than the recording head is set up to a reproducing mode, a pattern recorded by the recording head can be traced and whether recording can be normally executed without generating jam by a reproduced output level or not can be immediately monitored.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a rotary head type recording device, and particularly to a rotary head type recording device in which a plurality of rotary heads are arranged so as to simultaneously trace a recording medium. be.

[Prior Art] Conventionally, in a video tape recorder (VTR), confirmation of recording is as follows: (1) Recording is performed for a certain period of time, and then that portion is played back and confirmed on a monitor television. ■-The body type camera records one scene, and during the rec pause, the last few seconds of the scene are played back and confirmed by a so-called rec review.

That is, after recording, it was not known whether the recording was successful or not until later.

Furthermore, in general, in a VTR, a head mounted on a rotating drum rotates relative to the tape at a speed of several meters and seven seconds, and is very susceptible to clogging due to magnetic powder, dust, and the like.

[Problems to be Solved by the Invention] As mentioned above, when checking the recording of a VTR, the conventional method is used to check whether what was intended to be recorded or not was recorded due to causes such as head clogging. , there was a problem in that the user did not notice it during recording and could not notice it until later when playing it back, and furthermore, there was a problem in that important recorded scenes were not recorded.

This invention was made in order to solve this problem, and it is possible to monitor the recording head even during recording so that recording does not fail due to clogging or other malfunction of the head that is supposed to be recording. The purpose of the present invention is to provide a magnetic recording/reproducing device that can perform the following functions.

[Means for Solving the Problems] In order to achieve the above object, the rotary head type recording device of the present invention provides a rotary head type recording device that uses a head different from the head that is currently recording during the recording mode, and that The rotary head other than the head 1 traces the recording medium at the same time, and the head performs reproduction.

[Function] With the above configuration, by setting a head different from the head used for recording into the reproduction mode, the pattern recorded by the recording head is traced, and the recording is performed according to the reproduction output level. Does not cause clogging,
This is to immediately monitor whether the process has been carried out normally.

[Example] As an example of the present invention, a small diameter tram having a first head having the same azimuth angle facing each other by 180" and a second head having the same azimuth angle orthogonal to this and facing 180° A video tape recorder having a unit will be described.

This small-diameter type drum unit maintains compatibility with the drum diameter of a conventional drum unit in which heads with different azimuth angles are arranged 180' opposite each other, and has a diameter reduced to 180%.

When recording signals using such a small-diameter drum unit, there is a possibility that while a certain head is recording, a head that is not recording at the same azimuth angle as the recording head may trace the recording track. In this embodiment, by putting the head that is not used for recording into the playback mode, it is immediately monitored whether or not the recording head is able to record normally without becoming clogged.

FIG. 1 is a schematic diagram of a rotating drum having four small-diameter heads (hereinafter referred to as "small-diameter four heads") in a VTR which is an embodiment of the present invention, and FIG. 2 shows a tape traced by the heads of FIG. This shows a pattern diagram. Figure 1.

In FIG. 2, 1 and 3 are magnetic heads (hereinafter referred to as heads) having the same first azimuth angle, and 2°4 is orthogonal to this head 1.3, and is a head l.

A head having a second azimuth angle different from 3, 5 a rotating drum on which the heads 1, 2, 3.4 are mounted, 6 a magnetic tape, 7, 8, 9.10 a rotating drum 5 on which the magnetic tape 6 is mounted.
This is a guide post for winding the material at a predetermined angle, and while the angle of the winding was more than 180° in the conventional 2-head rotating drum, in the small-diameter 4-head drum in this embodiment, the angle is 270°. It is wrapped around the above angle range. Arrow 11 indicates the rotational direction of heads 1, 2, 3.4, and arrow 12 indicates the tape running direction during recording/normal playback.The number of rotations of the 0-rpm drum 5 is as follows in the NTSC system.
While the conventional rotating drum described above rotates at 1800 rpm, the drum of this embodiment rotates at 2700 rpm. Also, 13a is the track recorded by head 1, hereinafter 13
b, 13c.

13d, 13a', 13b' each have a head of 2°3
．． Tracks 4, 1, 2 are recorded sequentially. 13a
, 13c, 13a' or the same atsimus angle, 13b, 13d
, 13b' have an azimuth angle different from the above.

Figure 3 shows the recording pattern using a small-diameter 4-head drum.
FIG. 4 is a block diagram of a circuit that immediately monitors head clogging in this embodiment, and FIG. 5 shows the head switching signal in FIG. 4. This is a timing chart. In Fig. 4, 40 indicates a small diameter 4-height tram unit, and 41
4 is a tram motor that rotates the rotating drum in this drum unit 40; 42 is a driver circuit for the tram motor 41; 43 is a servo control circuit for controlling the driver circuit 42 and the capstan motor unit 44;
5 is attached to the rotating drum, and is attached to a frequency generator (FG) for detecting the rotation speed of the rotating drum and for controlling the phase of the rotating drum, and generates a signal synchronized with the rotation of the rotating drum. Pulse generator (PG)
) is shown. Further, 46 is a timing generation circuit that generates a timing signal based on a signal from the servo control circuit 43, and 47 is this timing generation circuit 46.
a head switching circuit that outputs a head switching signal for switching the four heads based on a signal from the head switching circuit 47; an amplifier 48 that amplifies the signal extracted from each head switched based on the signal from the head switching circuit 47; 4
9 is a detection circuit for detecting the signal reproduced from each head; 50 is a level determination circuit for determining whether or not the head is clogged by determining the level of the signal detected by the detection circuit 49; , 51 is this level judgment circuit 50
52 is a light emitting diode (LED) that emits light as a warning in response to a signal from the clogging warning circuit 51, and 53 is a light emitting diode (LED) that emits a warning signal to be recorded on a recording medium. 54 is a video signal processing circuit that processes a video signal among the input signals; 55 is an audio signal processing circuit that processes an audio signal; 56 is a signal input unit that processes four types of frequencies for tracking control; 57 is a mixing circuit for mixing the video signal, audio signal, and pilot signal to be recorded.

Further, FIG. 6 is a circuit diagram showing a specific example of the head switching circuit in FIG. 4.

3 to 6, when writing track 13a along the head operation direction arrow 11 is completed, the next head 2 reaches the beginning of writing track 13b. Further, the track width Tw of the recording head is generally set wider than the track width T remaining on the tape. At this time, the positions of heads 3 and 4 other than heads 1 and 2 are shown in FIG.

The lower end of head 3.4 is on line 14 and the position is head 1
．． It is three equal parts above 2. The head 3 having the same azimuth angle as the recording head 1 also has a track width T8, of which the width TP straddles the track recorded by the head I.

That is, as shown in the waveform of FIG. 5, the head switching circuit 47 turns ON the switch C of FIG. 6 to put the head 3, which is not used for recording, into the playback mode while the head L is recording, and its output level is detected. By doing so, it is possible to determine whether or not the head 1 has recorded normally without being clogged. The same holds true for heads 2, 3, 4°1, . . .

As described above, the timing generating circuit 46 sets the head that is not used for recording into the playback mode (
PB), extract the signal of the part that was just recorded, check the playback output level with the detection circuit 49, and make a level judgment with the level judgment circuit 50. If the playback level does not reach the set value, it is determined that there is a blockage. The clogging warning circuit 51 lights up the warning LED 52.

In addition, in this embodiment, another head with the same azimuth angle as the recording head is set to playback mode and used to judge whether or not recording has been performed. Detecting, for example, the level of the low frequency converted chroma signal, or the level of the pilot signal described above is also a circuit.

However, as in the head configuration described above, n heads (n≧3) are arranged with different phases by (31i0/n)'', and the tape is placed on a drum equipped with these heads [:t60
(n −1)/n ] ' A device of the type that winds the winding over an angular range of 1' is effective to apply the present invention since it is not necessary to provide a monitoring head even in a recording-only device.

Further, the present invention is not limited to the above-mentioned four-head configuration, but can also be applied to a type of drum having a normal diameter and having heads for each of the normal mode and the time mode.

[Effects of the Invention] As explained above, according to the present invention, an accident may occur in which important scenes were not recorded due to head clogging, etc., when what was originally intended to be recorded was later played back. It is possible to prevent this from happening in advance. That is, in a configuration that includes other heads that are not used for recording and that are in contact with the recording medium, the head other than the head that is recording is put into the playback state, and a signal is detected from the recorded recording track and its level is determined. It is possible to immediately monitor whether or not clogging has occurred. This allows the user to minimize time lost and damage caused by cleaning the head, etc.

[Brief explanation of the drawing]

1 is a schematic diagram showing the head configuration of a VTR according to an embodiment of the present invention, FIG. 2 is a diagram of a tape pattern traced by the head configured as shown in FIG. 1, and FIG. 3 is a diagram showing the head configured as shown in FIG. 1. Figure 4 is a block diagram of a circuit that immediately monitors head clogging in this embodiment, and Figure 5 shows the head switching signal in Figure 4. timing chart,
FIG. 6 is a circuit diagram showing a specific example of the head switching circuit in FIG. 4. In the figure. 1.2, 3, 4: Head 5: Rotating drum 6: Magnetic tape 40 Double drum unit 50 Double level judgment circuit 51: Clogging warning circuit 52: LED Agent Patent attorney 1) Haru Kitatake Figure 1 Figure 2 Figure 3

Claims (1)

[Claims] A rotation characterized in that a plurality of rotary heads are arranged so as to trace a recording medium at the same time, and during recording of a signal, a head other than the recording head that is tracing the recording medium is brought into a reproducing state. Head type recording device.