JPH08279984A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE: To utilize a sound signal for a time plus magnetic recording and reproducing device by setting up the occupied frequency band of a sound recording signal to a value lower than that of a video signal and recording the set value in the deep layer of a magnetic tape. CONSTITUTION: The occupied frequency band of a frequency-modulated wave recording signal for a sound signal is set up to a frequency band lower than the lower area of that of a video signal and recorded in a magnetic tape T by rotating magnetic heads Haa, Hab 180 deg. symmetrically arranged on a drum Du and having respectively different azimuth angles. A video recording signal is recorded on the tape T in which the sound signal has been recorded by rotating magnetic heads Hva, Hvb by 180 deg. symmetrically arranged on the drum Du and having prescribed azimuth angles different from that of the heads Haa, Hab. The video recording signal is recorded in a part close to the surface of the magnetic tape T, the sound recording signal is recorded in a deep layer part and n prescribed sound information recording traces are formed in a prescribed video information recording trace interval Tp. Consequently sound continued on a reproducing time base can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing apparatus, and more particularly, it has different azimuth angles and
Due to the rotation locus of the rotary magnetic head provided at the position of 0 degree symmetry, the magnetic tape is continuously wound at a predetermined constant running speed while being obliquely wound around at least a part of the peripheral surface of the drum. The present invention relates to a time-lapse type magnetic recording / reproducing apparatus which records a video signal by taking a frame.

[0002]

2. Description of the Related Art A video tape recorder as a typical example of a magnetic recording / reproducing apparatus in which a rotary magnetic head is used for a magnetic tape to record / reproduce information signals.
As one of (VTR), the position of the reference edge of the magnetic tape obliquely wound around at least a part of the peripheral surface of the drum is regulated by a guide portion provided on the drum, and There is a magnetic recording / reproducing apparatus (helical scanning type magnetic recording / reproducing apparatus) in which a recording / reproducing operation with respect to the magnetic tape is performed by a rotating magnetic head. 1 formed on a magnetic tape
A video signal for one field period can be recorded and reproduced for each record of a book.

The helical scan type magnetic recording / reproducing apparatus described above has conventionally been used as a monitoring (security) apparatus in combination with, for example, a monitoring (security) imaging apparatus (TV camera). Has been done. When the helical scanning type magnetic recording / reproducing apparatus is used in the above-described usage mode, the video signal is continuously output from the TV camera on the time axis at predetermined time intervals. A time-lapse magnetic recording / reproducing apparatus is used in which the video signal of the one field period or the one frame period extracted in 1 is recorded and reproduced on a magnetic tape. Conventionally, as a time-lapse type magnetic recording / reproducing apparatus, a video signal output from a surveillance (security) TV camera is recorded on a magnetic tape which is continuously run at a slow running speed at predetermined intervals. In the video signal output from the surveillance (crime prevention) TV camera, the magnetic tape in the stopped state is configured to be shot and recorded, or as disclosed in JP-A-58-62985. A VTR or the like has been proposed in which the magnetic tape is intermittently run so that the running speed of the magnetic tape becomes a specified running speed during normal reproduction operation only during a period in which frames are taken and recorded at predetermined intervals. It is coming.

[0004]

The above-mentioned time-lapse type magnetic recording / reproducing apparatus has been conventionally used in a store of a financial institution.
It is well known that it has been widely used for crime prevention in supermarket stores, convenience store stores and the like. By the way, as described above, the time-lapse magnetic recording / reproducing apparatus is used for monitoring (for crime prevention) T-recording.
Since the video signal output from the V camera is photographed and recorded on the magnetic tape at predetermined time intervals, even if the video content recorded on the magnetic tape is reproduced, a desired result is obtained from the reproduced image. Sometimes you can't get it. The above problems are
As described above, it may be possible to solve the problem by continuously recording the acoustic signal on the time axis on the magnetic tape on which the image is frame-recorded and using the reproduced acoustic signal. However, in the magnetic recording / reproducing apparatus of the type described above, since the magnetic tape repeats the operation of stopping and running, the above-mentioned solving means cannot be applied. In the magnetic recording / reproducing apparatus of the type described above, the magnetic tape is run at an extremely slow running speed. Therefore, when an audio signal is recorded on the audio track at the edge of the magnetic tape by the fixed audio head, S / N is good, and it is impossible to reproduce an audio signal with good intelligibility. As described above, in any of the conventional time-lapse magnetic recording / reproducing apparatuses described above, any of them can use the acoustic signal accompanying the frame-recorded image content recorded on the magnetic tape. There wasn't one, so a solution was sought.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a peripheral surface of a drum is formed by a rotation locus of a first type rotary magnetic head which has azimuth angles different from each other and which are provided at 180-degree symmetrical positions. Of the predetermined recording in the state of being obliquely wound around at least a part of the peripheral surface of the drum by the rotation locus of the rotary magnetic head of the first type in a state of being obliquely wound around at least a part of the On the magnetic tape continuously running at a constant running speed so as to obtain the trace interval Tp, recording traces of the frequency modulated wave type video signal are sequentially formed at the recording trace intervals of Tp, and the above-mentioned first Prior to the formation of the recording mark by each rotating magnetic head of the type, the magnetic tape has an occupied frequency band in a frequency band lower than the lower part in the occupied frequency band of the frequency modulated wave form video signal. A recording trace of an audio signal in the form of a frequency-modulated wave is sequentially formed by a rotation locus of a second type rotary magnetic head having an azimuth angle greatly different from that of the first type magnetic head described above. In the magnetic recording / reproducing apparatus, the above-mentioned first
In the recording traces sequentially formed on the magnetic tape at the recording trace intervals of Tp by the recording operation by each rotary head of the above type, n (however, n Provides a magnetic recording / reproducing apparatus in which a recording trace of 2 or more natural number) is formed.

[0006]

The magnetic tape wound obliquely around at least a part of the peripheral surface of the drum is provided with a predetermined recording mark interval T.
The vehicle is continuously run at a constant running speed so that p can be obtained. A predetermined number of rotations related to the vertical scanning period of the video signal to be recorded by the first type rotary magnetic heads having mutually different azimuth angles and provided at positions symmetrical by 180 degrees. Then, the recording traces of the video signal in the frequency modulated wave form are sequentially formed at the recording trace intervals of Tp by the rotation locus of the rotary magnetic head of the first type. The formation of the recording traces (recording traces of video information) sequentially formed at the recording trace intervals of Tp on the magnetic tape by the rotation loci of the rotating magnetic heads of the first type described above, Rotation of a second type rotary magnetic head having an azimuth angle greatly different from that of the first type rotary magnetic head in each record (recording trace of video information) by each type 1 rotary magnetic head. According to the locus, n (however, n by audio signals in the frequency modulated wave form having an occupied frequency band in a frequency band lower than the lower part in the occupied frequency band of the frequency modulated wave form video signal described above.
Forms a recording trace (natural information of 2 or more) (recording trace of audio information).

Among n recording traces (recording traces of voice information) of voice signals in the form of frequency-modulated waves which are continuous on the time axis and recorded on the magnetic tape by the rotary magnetic head of the second type. The recording information of is close to the surface of the magnetic tape when the recording trace of the video signal is recorded and formed by the frequency modulated wave by the video signal accompanied by the audio signal by the first type rotary magnetic head. The recorded information in the depth portion is erased, but the recorded information in the portion distant from the surface of the magnetic tape remains without being erased. That is, the recorded information of the video information is recorded in the portion close to the surface of the magnetic tape, and the recorded magnetic tape in which the recorded information of the audio signal is deeply recorded can be obtained.

From the recorded magnetic tape, the recorded magnetic tape is made to run at the running speed at the time of recording and is rotated by the first type rotary magnetic head and the second type rotary magnetic head described above. When the recorded information is reproduced, the frequency-modulated wave by the video signal is reproduced from the first type rotary magnetic head, and the frequency-modulated wave by the audio signal is reproduced from the second type rotary magnetic head. . By subjecting each of the frequency-modulated waves described above to frequency demodulation and then subjecting them to predetermined signal processing, a video signal in the frame-taken state and an audio signal in a continuous state on the time axis are reproduced. Will be.

By the recording operation by the rotary heads of the first type, the rotary heads of the second type are recorded in the recording traces (recording traces of video information) sequentially formed on the magnetic tape at the recording trace intervals of Tp. When an odd number of recording traces (recording traces of audio information) are formed by the recording operation by, the recording traces of the video information sequentially formed on the magnetic tape are always recorded in the video in the odd field period. The recording traces by the signal and the recording traces by the video signal in the even field period are sequentially and alternately adjacent to each other, and a reproduced image in a state in which good interlace scanning is performed can be easily obtained.

By the recording operation by each rotary head of the first type, the rotary heads of the second type are recorded in the recording traces (recording traces of video information) sequentially formed on the magnetic tape at the recording trace intervals of Tp. When an even number of recording traces (recording traces of audio information) are formed by the recording operation by, the recording traces of the video information sequentially formed on the magnetic tape are always recorded in the odd field period. Only the recording trace by the signal (or the recording trace by the video signal in the even field period) is provided. By providing a so-called H / 2 (H is 1 horizontal scanning period) processing circuit in the reproducing system, excellent interlace scanning is performed. It is possible to easily obtain a reproduced image in the state of being displayed.

As an example, it is assumed that the video signal to be recorded / reproduced is configured according to the scanning standard for performing the interlaced scanning of 2: 1 at the vertical scanning frequency of 60 Hz, and the VHS (registered trademark) system is used. Tape speed (3.3) in standard play mode (SP mode) of VTR standard
(35 cm / sec), using a magnetic tape capable of recording and reproducing for 120 minutes, the SP mode of 3.335c
With the tape speed of m / sec being 1/13, the first type of rotary magnetic head was used to form sequential video tracks on the magnetic tape with a track pitch (video track pitch) of 58 μm. When an audio track with a track width of 58 μm / 13 is formed by a rotary magnetic head, a 120-minute magnetic tape is used to record 26 hours of frames (60/13 frames per second) and continuously for 26 hours. Therefore, the sound signal is recorded in good condition.

As another example, it is assumed that the video signal to be recorded / reproduced is configured in accordance with a scanning standard for performing interlaced scanning of 2: 1 at a vertical scanning frequency of 60 Hz, and VHS (registered) is registered. A magnetic tape capable of recording / reproducing for 160 minutes at a tape speed (3.335 cm / sec) in a standard play mode (SP mode) in the VTR standard of the trademark system is used, and in the SP mode described above.
With the tape speed of 335 cm / sec set to 1/9, the first type of rotary magnetic head was used to form sequential video tracks on the magnetic tape at a track pitch (video track pitch) of 58 μm. When an audio track with a track width of 58 μm / 9 is formed by a rotating magnetic head, a 24-hour frame recording (60/9 frames per second) is performed with a 160-minute magnetic tape, and continuous recording is performed for 24 hours. Therefore, the sound signal is recorded in good condition.

As still another example, the video signal to be recorded / reproduced has a vertical scanning frequency of 60 Hz and a video signal of 2 Hz.
The tape speed (about 1.112 cm / sec) in the extended play mode (EP mode) in the VHS (registered trademark) VTR standard is assumed to be configured according to a scanning standard for performing interlaced scanning on a one-to-one basis. A magnetic tape capable of recording and reproducing for 160 minutes was used, and the tape speed of about 1.112 cm / sec in the EP mode was set to 1/3, and a 19 μm track was formed on the magnetic tape by the first type of rotary magnetic head. When a video track is sequentially formed at a pitch (video track pitch), and an audio track having a track width of 19 μm / 3 is formed by the second type rotary magnetic head, a magnetic tape for 160 minutes is used. 24 hours frame recording (60 / s / s)
(3 frames), and good audio signals are continuously recorded for 24 hours.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The specific contents of the magnetic recording / reproducing apparatus of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a block diagram showing a schematic configuration of an example of a magnetic recording / reproducing apparatus of the present invention. In the upper part of FIG. 1, some mechanical parts considered necessary for explaining the magnetic recording / reproducing apparatus of the present invention are shown. In the drum base DB fixed to the machine plate 35,
A drum structure including a fixed drum Dd and an upper drum Du driven and rotated by a drum motor 36, guide rollers 39 and 40, inclined poles 41 and 42, and the like are attached. 38 is a drum rotation pulse (DFF signal) generator, and 37 is a drum FG signal generator. Further, 43 is a control head, 44 is a capstan, 45 is a pinch roller, 46 is a bearing portion of the pinch roller 45, 30 is a capstan motor, and 31 is a capstan FG signal generator. The drum rotation pulse (DFF signal) generator 38, the drum FG signal generator 37, the capstan FG signal generator 31 and the like are constituted by, for example, a rotating disk fixed to a rotating shaft and a photo interrupter. ,
Alternatively, a magnetic disk and a magnetic disk having a predetermined magnetic pattern fixed to the rotary shaft may be used.

Upper drum Du in the above-mentioned drum structure
Is driven and rotated at a predetermined rotation speed under the control of the drum motor drive control circuit 25. The upper drum Du has a first azimuth angle different from each other and a first kind of rotation used for recording a frequency-modulated wave signal by a video signal on a magnetic tape at a position symmetrical with 180 degrees. Besides being provided with a magnetic head, it is used for recording a frequency-modulated wave signal by an audio signal on a magnetic tape prior to the formation of a recording trace by each rotary magnetic head of the first type described above. A second type of rotating magnetic head is also provided. The magnetic tape T that is obliquely wound around a part of the peripheral surface of the drum is a capstan motor drive control circuit 29.
44 which rotates at a predetermined speed under the control of
And is pinched by the pinch roller 45 so that it can travel at a predetermined traveling speed. It should be noted that, in order to simplify the drawing, in FIG. 1, a concrete illustration of the running path of the magnetic tape between the guide roller 40 and the control head 43 is omitted.

In FIG. 2A, Hva and Hvb are
It is a rotary magnetic head of the first kind mounted at 180-degree symmetrical positions on the upper drum Du, and also has a Ha
a and Hab are the rotary magnetic heads Hv of the first type described above.
a, Hvb is a rotary magnetic head of the second type mounted at a position preceding the corresponding one in a, Hvb and at a position symmetrical by 180 degrees on the upper drum Du.
FIG. 2B is a diagram showing a configuration example of the above-described first and second types of rotary magnetic heads Hva, Hvb, Haa, Hab, and the first type of rotary magnetic head Hva,
Hvb is a different azimuth angle ± α degrees (for example, the azimuth angle of the magnetic gap of the rotary magnetic head Hva is +6 degrees,
The azimuth angle of the magnetic gap of the rotating magnetic head Hvb is -6.
Degree).

The second type of rotary magnetic head Ha
a and Hab are the rotary magnetic heads H of the first type described above.
An extremely large azimuth angle ± β degree compared to the azimuth angle ± α degrees of va and Hvb (for example, the azimuth angle of the magnetic gap of the rotary magnetic head Haa is −45 degrees, the rotary magnetic head Hab
The azimuth angle of the magnetic gap is +45 degrees). In FIG. 2B, tva is a recording mark formed by the rotary magnetic head Hva, and tvb is a rotary magnetic head Hv.
b is a recording mark formed by b, taa is a recording mark formed by the rotating magnetic head Haa, and tab is also
Is a recording mark formed by the rotating magnetic head Hab. The reference numerals for indicating the above-mentioned recording marks are similarly used for the recording marks shown in FIGS. 3 and 4.
The numbers in the reference numerals attached to the recording marks in FIGS. 3 and 4 are for distinguishing the recording marks sequentially formed on the time axis for each rotary magnetic head.

In the magnetic recording / reproducing apparatus of the present invention, a video signal formed in accordance with a predetermined scanning standard (in the following description, horizontal scanning frequency fh, vertical scanning frequency 60 Hz, 2: 1 interlaced scanning scanning) An occupied frequency band Zv of a recording signal (frequency modulated wave signal of a video signal) by a frequency modulated wave signal obtained as a modulation wave of a video signal configured according to the standard) and an acoustic signal (audio signal). ) As a modulated wave, the relationship between the recording signal (frequency modulated wave signal of a voice signal) occupied by the frequency modulated wave signal and the occupied frequency band Zs is as illustrated in FIG. Frequency occupied by the signal is lower than the lower part in the occupied frequency band Zv of the frequency modulated wave form video signal. In addition to satisfying the relationship of being located in the area, both the frequency-modulated wave signal of the video signal and the frequency-modulated wave signal of the audio signal are recorded on the magnetic tape T by the rotary magnetic head. First, the frequency-modulated wave signal of the voice signal is recorded by the second type rotary magnetic heads Haa and Hab as traces taa1 → tab1 → taa2 → tab3 → (FIGS. 3 and 4).
2) rotation of the second kind of the frequency modulated wave signal by the video signal on the magnetic tape T of the portion which has been recorded by the frequency modulated wave signal by the audio signal. By recording with the magnetic heads Hva and Hvb, the recorded information of the video information is recorded in the portion near the surface of the magnetic tape, and the recorded information of the audio signal is recorded in the deep layer. In the magnetic recording / reproducing apparatus having the structure as described above, the frequency-modulated wave signal generated by the audio signal is placed within the recording mark interval Tp of the record mark recorded by the rotary magnetic head. Recording traces for recording signals are formed by the rotating magnetic head in the number of n (where n is a natural number of 2 or more).

Next, referring to FIG. 3 and FIG. 4, recording traces of video information which are frame-recorded on the magnetic tape T by the magnetic recording / reproducing apparatus of the present invention and the magnetic tape T continuously on the time axis. The relationship between the audio information recorded in and the recording trace will be described. First, in FIGS. 3 and 4, taa1, taa2, t
aa3, taa4 ... Denote recording marks formed on the magnetic tape T by the second type rotary magnetic head Haa, and tab1, tab2, tab3, tab4 ... Are recorded by the second type rotary magnetic head Hab. The recording marks formed on the magnetic tape T are indicated by tva1, tva2, ..., The recording marks formed on the magnetic tape T by the second type rotary magnetic head Hva, and tvb14 are indicated by the second mark. The recording marks formed on the magnetic tape T by the rotary magnetic heads Hvb of the above types are shown.

The video signal to be recorded / reproduced is 60
It is assumed that it is constructed in accordance with a scanning standard for performing an interlaced scanning of 2: 1 at a vertical scanning frequency of Hz, and it is mounted at a 180-degree symmetrical position on the upper drum Du.
Each of the rotary magnetic heads of the rotary magnetic heads is arranged from one edge of the magnetic tape T wound around the drum circumferential surface over an angle of slightly more than 180 degrees at the central angle of the drum to the other. If the number of rotations of the rotary magnetic head (the number of rotations of the upper drum Du) is set so that a video signal of one vertical scanning cycle can be recorded up to near the edge of the One rotary magnetic head of the two rotary magnetic heads provided at the position is attached to the magnetic tape T during the half rotation of the upper drum Du,
A recording trace is formed by a signal corresponding to one vertical scanning period, and during the next half rotation of the upper drum Du, a magnetic tape is produced by the other rotary magnetic head of the above two rotary magnetic heads. It is well known that a recording trace is formed on T by a signal corresponding to the next one vertical scanning period.

Now, tva1, va2 ... Shown in FIG.
Is a sequential recording trace of the video information formed on the magnetic tape T by the first type rotary magnetic head Hva having an azimuth angle of + α degrees, and tvb1 ...
Is a recording trace by the image information formed on the magnetic tape T by the first type rotary magnetic head Hvb having an azimuth angle of −α degrees. Each rotating magnetic head (Hva, H
vb, Haa, Hab) are attached to the upper drum Du that is driven and rotated at a predetermined rotation speed and rotation phase under the control of the drum motor drive control circuit 25, On the recording trace formed on the magnetic tape T by the rotary magnetic heads Hva and Hvb, video information of one vertical scanning period between adjacent vertical synchronizing signals in the video signal is recorded in a state of being properly recorded. Further, the magnetic tape T is driven by a capstan motor so that the above-mentioned sequential recording traces are continuously run at a predetermined constant speed so that the magnetic tape T is formed at a predetermined recording trace interval TP. The traveling speed and the phase are controlled by the control operation of the control circuit 29.

By the way, by the above-mentioned two rotary magnetic heads Hva and Hvb of the first type, recording traces tva1, tvb1 and tva2 by the image information formed on the magnetic tape T with a predetermined recording trace interval TP. ... is not formed by the video signals of successive vertical scanning periods continuous on the time axis, but is a predetermined ratio from among the video signals of successive vertical scanning periods continuous on the time axis. Is a recording trace in which a video signal in the vertical scanning period obtained by performing frame dropping at N is recorded. And, the ratio N of dropping pieces is 2
Although the above natural numbers are used, when N is an odd number, the recording traces of the video information sequentially formed on the magnetic tape are always the recording traces of the video signal in the odd field period and the even field. This is a desirable mode of implementation in that the recorded traces of the video signals of the periods are sequentially and alternately adjacent to each other, and a reproduced image in a state in which good interlace scanning is performed can be easily obtained. FIG. 3 and FIG. 4 exemplify recording trace patterns when the frame drop ratio N is set to 5, as described later.

In the example shown in FIG. 4, the video information recorded on the recording trace tva1 by one rotary magnetic head Hva of the two rotary magnetic heads Hva, Hvb of the first type is, for example, m in the video signal. Assuming that the video signal has the th vertical scanning period, the video information recorded on the recording trace tvb1 by the other rotary magnetic head Hvb of the above two first type rotary magnetic heads Hva and Hvb is: The video signal has the (m + 5) th vertical scanning period of the video signal, and the video information recorded on the recording trace tva2 by the rotary magnetic head Hva is the (m + 10) th vertical scanning period of the video signal.

That is, when the frame drop ratio N is 5, the video signal of the m-th vertical scanning cycle in the video signal is continuously transmitted at a predetermined constant speed by the rotary magnetic head Hva of the first type. After being recorded on the magnetic tape T running on the magnetic tape T, the video signal of the (m + 5) th vertical scanning period in the video signal is recorded on the magnetic tape T by the first type rotary magnetic head Hvb. (M + 1) th, (m + 2) th in the existing video signal,
The video signals of the (m + 3) th and (m + 4) th vertical scanning periods are discarded without being recorded on the magnetic tape T. On the other hand, the magnetic tape T is made to always run at a predetermined constant speed, and the two recording magnetic heads Haa, Hab of the second type are used to sequentially record traces taa1 → tab1 → taa2 → tab3 of audio information. → taa4 → tab4 → taa5
.. tab5.fwdarw.taa6.fwdarw.tab6.fwdarw.taa7 ... Is formed at the recording mark interval TP / 5 (when N = 5) as illustrated in FIGS.

FIGS. 3 and 4 show sequential recording traces taa1 → tab1 → taa2 → tab3 → taa4 ... By the audio information continuously recorded on the magnetic tape T on the time axis as described above, and the frame drop. In this state, recording of sequential recording traces tva1, tvb1, tva2 ... By the video information intermittently recorded on the time axis,
It is a figure for illustrating and explaining under what kind of time relationship it is formed on the magnetic tape T. Each recording mark shown in the figure is attached to the upper drum Du. It is formed on the magnetic tape T by a semi-strong rotation locus of each specific one of the plurality of rotating magnetic heads.

The recording operation of the magnetic recording / reproducing apparatus shown in FIG. 1 will now be described with reference to FIGS. 3 and 4 as well. When a predetermined instruction input is given from an operation unit (not shown) so that the magnetic recording / reproducing apparatus operates in the recording operation mode, a switching control signal output from a control circuit (not shown) causes a change in FIG. The respective movable contacts of the changeover switches 23, 27, 33, 34 shown are switched to the fixed contact R side. In the frequency modulator 5 to which the composite video signal to be recorded is supplied via the input terminal 1, a predetermined carrier wave is frequency-modulated using the composite video signal as a modulation wave, and Zv in FIG. A frequency-modulated wave signal is generated by a video signal having an occupied frequency band as shown, and this is generated by the video signal selection circuit 6
Supply to.

Further, in the sync separation circuit to which the composite video signal is supplied through the input terminal 1, the vertical sync signal obtained by sync separation from the composite video signal is waveform-shaped and the vertical scanning cycle is obtained. Output as a signal. The signal of the vertical scanning period output from the vertical sync separation circuit 22 is
The reference signal is given to the phase comparator 24 via the fixed contact R and the movable contact of the changeover switch 23, and is given to the phase comparator 28 via the fixed contact R and the movable contact of the changeover switch 27. The reference signal of the vertical scanning period output from the vertical sync separation circuit 22 is also supplied to the control head 43 via the fixed contact R and the movable contact of the changeover switch 34.

In the phase comparator 24, the reference signal of the vertical scanning period and the drum rotation pulse (DFF) generated by the drum rotation pulse (DFF signal) generator 38 are generated.
Signal) and gives an error signal generated corresponding to the phase error between the two signals to the drum motor drive control circuit 25. The drum motor drive control circuit 25 is also supplied with the drum FG signal generated by the drum FG signal generator 37. In the drum motor drive control circuit 25, the rotational speed and rotation of the first type rotary magnetic head The drive current that can bring the phase (which may be referred to as the rotational speed and rotational phase of the drum motor 36, and the upper drum Du rotational speed and rotational phase) to a desired state can be applied to the drum motor 36.
Supply to.

As a result, each rotary magnetic head mounted on the upper drum Du driven and rotated by the drum motor 36, that is, a position having a different azimuth angle and 180 ° symmetry, is subjected to a frequency control by a video signal. For forming the first type rotary magnetic heads Hva, Hvb used for recording the modulated wave signal on the magnetic tape T, and the recording marks tva, tvb by each of the first type rotary magnetic heads Hva, Hvb described above. Previously, the rotational speed and rotational phase of the second type rotary magnetic heads Haa, Hab used for recording the frequency-modulated wave signal by the audio signal on the magnetic tape T are also controlled to a desired state, On the magnetic tape T by the above-mentioned first type of rotary magnetic heads Hva and Hvb, one vertical scanning period between adjacent vertical synchronizing signals in the video signal is displayed. It becomes possible to form a recording trace of a state in which the video information in the interval is properly recorded.

In the phase comparator 28, the signal of the vertical scanning period supplied from the vertical sync separation circuit 22, that is, the vertical sync signal in the composite video signal to be recorded corresponds to the signal. The reference signal of the vertical scanning period and the capstan FG signal generated by the capstan FG signal generator 31 are frequency-divided by the frequency divider 32 and then supplied through the fixed contact and the movable contact of the changeover switch 33. The output signal is output to the capstan motor drive control circuit 29 after phase comparison with the comparison signal. In the capstan motor drive control circuit 29, one vertical scan obtained by performing frame dropping at a predetermined ratio N from the video signals in the successive vertical scan periods which are continuous on the time axis. The video signals of the period are sequentially recorded by the video information by the two rotary magnetic heads Hva and Hvb of the first type with a predetermined recording track interval TP.
Reference signals corresponding to the traveling speeds required to form va1, tvb1, tva2 ... On the magnetic tape T are set.

The capstan motor drive control circuit 29 is also supplied with the capstan FG signal generated by the capstan FG signal generator 31, and the capstan motor drive control circuit 29 operates as described above. By comparing the capstan FG signal with a reference signal corresponding to the traveling speed required for the magnetic tape,
To allow the magnetic tape T to run at a predetermined running speed so that the recording marks by the video signals dropped by a predetermined ratio N can be recorded on the magnetic tape T at a predetermined recording mark interval TP. And the phase comparator 28 described above.
Using the error signal supplied to the capstan motor drive control circuit 29 from the magnetic tape T, the magnetic tape T is run so that the phase relationship between the composite video signal to be recorded and the vertical synchronizing signal is in a desired state. The drive current is supplied to the capstan motor 30 so that it can be driven.

By the control operation of the capstan motor drive control circuit 29 described above, the magnetic tape T obliquely wound around a part of the peripheral surface of the drum has a continuous vertical scanning period which is continuous on the time axis. Image signals in each vertical scanning period obtained by performing frame dropping at a predetermined rate N from among the image signals of the above-mentioned two types of the above two rotary magnetic heads Hv of the first type.
a, Hvb and a capstan 44 that rotates at a predetermined rotation speed at a running speed such that a sequential recording trace tva1, tvb1, tva2 ... With image information is formed with a predetermined recording trace interval TP. , And can be continuously run while being sandwiched between the pinch rollers 45.

During the recording operation of the magnetic recording / reproducing apparatus, the frequency-modulated wave signal of the video signal output from the frequency modulator 5 and supplied to the video signal selection circuit 6 is supplied to the video signal selection circuit 6. , A frequency-modulated wave signal in the vertical scanning period to be recorded in a state in which frame dropping has been performed at a predetermined ratio N, from among video signals in successive vertical scanning periods on the time axis. Then, it is supplied to the video information recording amplifiers 7 and 8. The frequency-modulated wave signal generated by the video signal output from the video information recording amplifier 7 is a fixed contact R1 in the recording / reproducing switch 21.
The frequency-modulated wave signal based on the video signal output from the video information recording amplifier 8 is applied to the fixed contact R2 in the recording / reproduction changeover switch 21.

Fixed contact R in the recording / reproducing switch 21
The frequency modulated wave signal by the video signal supplied to 1 is
It is supplied to the rotary magnetic head Hva of the first type through the movable contact v1 and a rotary transformer (or brush and slip ring) not shown, and also to the fixed contact R2 in the recording / reproduction changeover switch 21. The frequency-modulated wave signal of the video signal is supplied to the first type rotary magnetic head Hvb via the movable contact v2, a rotary transformer (or brush and slip ring) not shown, and the like.

Next, an audio signal to be recorded, such as an audio signal accompanying the composite video signal to be recorded, other audio signals, etc., is input to the frequency modulator via the input terminal 3. 15 are supplied. The frequency modulator 1
In 5, a predetermined carrier wave is frequency-modulated by using an audio signal as a modulation wave to generate a frequency-modulated wave signal by an audio signal having an occupied frequency band as shown by Zs in FIG. The audio information recording amplifier 16 is supplied. The frequency-modulated wave signal of the audio signal has a relationship that its occupied frequency band Zs is located in a lower frequency band than the lower part of the occupied frequency band Zv of the frequency-modulated wave form video signal. Will be satisfied. The frequency-modulated wave signal generated by the audio signal output from the audio information recording amplifier 7 is applied to the fixed contact R3 in the recording / reproduction changeover switch 21, and the frequency-modulated wave signal generated by the audio signal is transferred to the movable contact v3 or The rotary magnetic head H of the second type is passed through a rotary transformer (or a brush and a slip ring) not shown.
It is supplied to aa and Hab. The curve Zc shown by the dotted line in FIG. 5 shows the occupied frequency band Zc of the low-frequency conversion carrier color signal when the color TV signal is the recording target.

When the video signal to be recorded / reproduced by the magnetic recording / reproducing apparatus is a video signal configured according to the horizontal scanning frequency fh, the vertical scanning frequency of 60 Hz, and the scanning standard of the interlaced scanning of 2: 1. Is the drum motor 36
Since the upper drum Du is driven and rotated at a rotation speed of 30 revolutions per second, the magnetic tape is driven by a specific semi-rotational strong locus of each one of the plurality of rotary magnetic heads attached to the upper drum Du. A signal for one vertical scanning period can be recorded in the recording trace formed at T. Now, after the magnetic recording / reproducing apparatus in which the ratio of dropped frames is set to N, the vertical synchronizing signal first appears after the time when the recording operation becomes possible after the recording operation mode is set ( N
-1) During the vertical scanning period, a control circuit (not shown) controls the video signal selection circuit 6 so that no output signal is output.

On the other hand, the frequency-modulated wave signal by the audio signal output from the audio information recording amplifier 16 is the vertical synchronizing signal which first appears after the recording operation becomes possible after the recording operation mode is set. During the period from the point of time to the point of ending the recording operation, the second type rotary magnetic head Haa via the fixed contact R3 and the movable contact v3 in the recording / reproducing changeover switch 21 and the rotary transformer (not shown). , Hab continues to be supplied. Then, the frequency-modulated wave signal by the audio signal is sequentially recorded on the magnetic tape T by the second type rotary magnetic heads Haa, Hab during the above period.

Next, the (N-1) vertical scanning period ends from the time of the vertical synchronizing signal first appearing after the time when the recording operation becomes possible, and the (N-1) vertical scanning period is illustrated in the figure during the Nth vertical scanning period. The video signal selection circuit 6 outputs a frequency-modulated wave signal by the video signal of the N-th vertical scanning period under the control of the control circuit which is not provided. After being amplified by the recording amplifier 7, it is supplied to the rotary magnetic head Hva of the first type through the fixed contact R1 and the movable contact v1 in the recording / reproduction changeover switch 21 and a rotary transformer (not shown), and is supplied to the magnetic tape T. Will be recorded.

Next, during a vertical scanning period from the (N + 1) th to the (2N-1) th vertical scanning period from the time of the vertical synchronizing signal first appearing after the time when the recording operation becomes possible, a control not shown is performed. After the circuit controls the video signal selection circuit 6 so that no output signal is output, during the 2Nth vertical scanning period, the control circuit (not shown) controls the video signal selection circuit 6 to output the first Nth signal. A frequency-modulated wave signal based on the video signal in the vertical scanning period is output,
The frequency-modulated wave signal of the video signal in the one vertical scanning period is amplified by the video information recording amplifier 8 and then passed through the fixed contact R2 and the movable contact v2 in the recording / reproduction changeover switch 21 and a rotary transformer (not shown). It is supplied to the first type rotating magnetic head Hvb and recorded on the magnetic tape T. As described above, by the video signal of one vertical scanning period for every iNth (where i is 1, 2, 3, ...) From the time of the vertical synchronizing signal that first appears after the time when the recording operation becomes possible. Sequential recording traces of frequency modulated wave signal tva,
tvb ... is two rotary magnetic heads Hva of the first type,
By the sequential and alternating recording operation by Hvb, the recording mark intervals TP are formed on the magnetic tape T.

By the way, the recording information by the audio information recorded in the sequential recording traces formed on the magnetic tape T by the second type rotary magnetic heads Haa and Hab are alternately recorded. Types of rotary magnetic heads Hva
(Or Hva), the recorded content of the portion near the surface of the magnetic tape T is erased during the recording operation of the recorded information by the video information, so that the reproduction output is 12d.
However, as described above, the recorded information based on the audio information has a lower occupied frequency band Zs than the lower part of the occupied frequency band Zv of the frequency-modulated wave form video signal. Since it is located in the band, the recorded information recorded in the magnetic layer in the portion distant from the surface of the magnetic tape is recorded on the magnetic tape T as so-called deep layer recording.
It is well known that the magnetic recording layer is left in the magnetic layer of the magnetic recording medium of the present invention. The recording information in the n recording traces (recording traces of audio information) by the audio signal in the form of a modulated wave is a recording trace of the video signal by the frequency-modulated wave by the video signal by the first type rotary magnetic heads Hva and Hvb. Even if the recorded information at the depth near the surface of the magnetic tape is erased when is recorded, the recorded information of the video information is recorded near the surface of the magnetic tape, and The recorded information is a recorded magnetic tape in a state of being deeply recorded.

FIGS. 3A to 3H and FIG. 4 show the frequency-modulated wave signal by the audio signal during the recording operation of the magnetic recording / reproducing apparatus in which the frame drop ratio N is set to 5. Sequential recording traces taa1, tab1, taa2, tab2 ...
Are sequentially formed by the second type rotary magnetic heads Haa and Hab, and the sequential recording traces tva1, tvb1, tva2 by the frequency-modulated wave signal of the video signal.
Shows an example of a state in which the rotary magnetic heads Hva and Hvb of the first type are sequentially formed. In addition,
In FIG. 4, the second layer is formed on the magnetic layer of the magnetic tape T.
With the rotary magnetic heads Haa and Hab of the type, the sequential recording marks taa are generated by the frequency-modulated wave signal of the audio signal.
After the formation of 1, tab1, taa2, tab2, ..., Sequential recording traces tva1, tv by the frequency modulated wave signal by the video signal by the first type rotary magnetic heads Hva, Hvb
In order to clearly show the state after b1, tva2 ... Is formed, a sequential recording trace tva which should have been formed by the frequency modulated wave signal by the video signal for the upper part in the figure.
The illustration of 1, tvb1, tva2, ... Has not been made.

Next, the magnetic recording / reproducing shown in FIG. 1 is performed from the recorded magnetic tape T in the state in which the recording trace by the video information and the recording trace by the audio information are recorded by the recording operation as described above. A case where the recorded information is reproduced by the device will be described. When a predetermined instruction input is given from an operation unit (not shown) so that the magnetic recording / reproducing apparatus operates in the reproduction operation mode, a switching control signal output from a control circuit (not shown) causes Changeover switches 23, 27, 3 shown
The respective movable contacts in 3, 34 are switched to the fixed contact P side. By switching the movable contacts of the changeover switches 23 and 27 to the fixed contact P side, the reference signal oscillated by the reference oscillator 26 is supplied to the phase comparator 24 and the phase comparator 28.

Therefore, in the phase comparator 24, the reference signal generated by the reference signal generator 26 and supplied to the phase comparator 24 via the fixed contact P and the movable contact of the changeover switch 23 and the drum rotation pulse. (DFF signal) generator 3
The phase comparison operation with the drum rotation pulse (DFF signal) generated in 8 is performed, and the error signal generated corresponding to the phase error between the above two signals is output to the drum motor drive control circuit 25.
Give to. In the drum motor drive control circuit 25 to which the drum FG signal generated by the drum FG signal generator 37 is also supplied, the rotational speed and rotational phase of the first type rotary magnetic head (rotational speed and rotational phase of the drum motor 36, And the upper drum Du rotation speed and rotation phase) may be supplied to the drum mode 36 with a drive current that can bring them into a desired state. Therefore, each rotary magnetic head mounted on the upper drum Du driven and rotated by the drum motor 36, that is, an image recorded on the magnetic tape T at a position having a different azimuth angle and 180 degrees symmetry. The first type of rotary magnetic heads Hva, Hvb used for reproducing the frequency modulated wave signal by the signal, and the first type used for reproducing the frequency modulated wave signal by the sound signal recorded deeply on the magnetic tape T. The two types of rotary magnetic heads Haa and Hab also rotate in a state in which the number of rotations and the rotation phase are controlled to desired states.

In the phase comparator 28, the changeover switch 27 is generated by the reference signal generator 26.
Error signal by comparing the phase of the reference signal supplied to the phase comparator 28 via the fixed contact P and the movable contact of the control signal and the control signal reproduced by the control head 43 from the control track on the recorded magnetic tape T. Is output, and the capstan motor drive control circuit 2
Give 9 In the capstan motor drive control circuit 29, one vertical scan obtained by performing frame dropping at a predetermined ratio N from the video signals in the successive vertical scan periods which are continuous on the time axis. The video signal of the period is the above-mentioned first
With two rotating magnetic heads Hva, Hvb of
At a predetermined recording mark interval TP, a reference signal corresponding to the running speed required to form the sequential recording marks tva1, tvb1, tva2, ... Of video information on the magnetic tape T is set. .

The capstan motor drive control circuit 29 is also supplied with the capstan FG signal generated by the capstan FG signal generator 31. In the capstan motor drive control circuit 29, the capstan motor drive control circuit 29 is operated. The stun FG signal is compared with a reference signal corresponding to the traveling speed required for the magnetic tape, and each recording trace recorded on the recorded magnetic tape T is recorded by the rotary magnetic head. In order to allow the magnetic tape T to run at a running speed that allows the corresponding one to work well, the error signal supplied from the phase comparator 28 to the capstan motor drive control circuit 29 is used. Then, the magnetic tape T is run so that each of the rotary magnetic heads described above can satisfactorily follow each of the sequential recording marks that are targeted for reproduction. Supplying a driving current which can cause the capstan motor 30.

By the control operation of the capstan motor drive control circuit 29, the recorded magnetic tape T, which is obliquely wound around a part of the peripheral surface of the drum, is recorded on the recorded magnetic tape T. The recording magnetic head rotates at a predetermined rotation speed at a traveling speed at which the reproducing operation can be performed in a state in which the corresponding rotary magnetic heads of the first and second types track the recording trace well. Capstan 44
Then, it can be continuously run while being sandwiched between the pinch rollers 45. If necessary, each rotary magnetic head described above is attached to an actuator that performs a displacement operation in accordance with a tracking control signal output from a tracking control circuit so that each rotary magnetic head can properly track a corresponding recording trace. May be.

Next, by the reproducing operation of the magnetic recording / reproducing apparatus, the frequency of the video signal sequentially reproduced from the sequential recording traces tva1, tva2 ... Of the recorded magnetic tape T by the first type rotary magnetic head Hva. The modulated wave signal is
The movable contact v1 of the recording / reproducing switch 21 from the input terminal 47
And the fixed contact P1 to the preamplifier 9, and the frequency of the video signal reproduced from the sequential recording traces tvb1, tvb2, ... Of the recorded magnetic tape T by the first type rotating magnetic head Hvb. The modulated wave signal is supplied from the input terminal 48 to the preamplifier 10 via the movable contact v2 and the fixed contact P2 of the recording / reproducing switch 21. The frequency-modulated wave signal based on the reproduced video signal amplified by each of the preamplifiers 9 and 10 is a signal selection circuit 11.
, A frequency modulated wave signal based on a video signal reproduced by one of the first type rotary magnetic heads Hva (or Hvb) which is reproducing a frequency modulated wave signal based on a video signal from the recorded magnetic tape T is selected. And feed it to the bandpass filter 12.

The band pass filter 12 extracts a signal component in the frequency band (frequency domain indicated by Zv in FIG. 5) in which the frequency-modulated wave signal by the reproduced video signal exists, and extracts it. It is supplied to the frequency demodulator 13 to perform frequency demodulation. The video signal frequency-demodulated by the frequency demodulator 13 is output as a reproduced video signal from the output terminal 2 after being subjected to predetermined signal processing by the reproduced video signal processing circuit 14. In the explanation so far,
For simplification of description, it is assumed that the video signal to be recorded / reproduced is only the luminance signal (monochrome signal). However, in the magnetic recording / reproducing apparatus of the present invention, for example, NTS is used.
Like the C signal, a color TV signal configured by band-sharing multiplexing two color difference signals in the band of the luminance signal, the above two color difference signals occupy the frequency region Zc shown by the dotted line in FIG. A recording signal in a signal form in which the low-frequency conversion carrier signal as described above is frequency-multiplexed with the low-frequency conversion carrier signal and the frequency-modulated wave signal by the luminance signal is recorded and reproduced on the magnetic tape T. However, in that case, the color demodulation operation is performed in the reproduction video signal processing circuit 14 described above.

Next, by the reproducing operation of the magnetic recording / reproducing apparatus, the sequential recording marks taa1, tab of the recorded magnetic tape T are recorded by the first type rotating magnetic heads Haa, Hab.
The frequency-modulated wave signal by the audio signal reproduced from 1, taa2, tab2, ...
1 through the movable contact v3 and the fixed contact P3 of the preamplifier 17
Is supplied to. The frequency-modulated wave signal based on the reproduced audio signal amplified by the preamplifier 17 is supplied to the bandpass filter 18. The band pass filter 1
In 8, the signal component of the frequency band (frequency region indicated by Zs in FIG. 5) in which the frequency-modulated wave signal by the reproduced audio signal is present is extracted and supplied to the frequency demodulator 19 Demodulate. The frequency demodulator 19
The reproduced audio signal processing circuit 20 performs predetermined signal processing on the audio signal frequency-demodulated by. That is, in the reproduction audio signal processing circuit 20, for example, the audio signal supplied thereto is given to the sample hold circuit,
The noise in the joint portion of the audio signal reproduced from the two second rotary magnetic heads Haa, Hab is removed, and then a known signal processing operation is performed on the audio signal by a de-emphasis circuit, a noise removal circuit, or the like. . The output signal from the reproduced audio signal processing circuit 20 is output to the output terminal 4 as a reproduced audio signal.

As described above, in the magnetic recording / reproducing apparatus of the present invention, the recorded magnetic tape is made to run at the running speed at the time of recording, and the rotary magnetic head H of the first type described above is used.
va, Hvb, and the second type rotary magnetic head Haa,
When the recorded information is reproduced from the recorded magnetic tape by the Hab, the frequency-modulated wave signal by the video signal is reproduced from the video tracks tva, tvb by the first type rotary magnetic heads Hva, Hvb, and the second kind is also reproduced. In the rotating magnetic heads Haa and Hab, the audio tracks ta and tb
To reproduce a frequency modulated wave signal by an audio signal. Then, by subjecting each of the frequency modulated wave signals described above to frequency demodulation, and then subjecting them to predetermined signal processing, the video signal in the frame-taken state and the audio signal in a state continuous on the time axis Is played.

Each rotary head Hva, Hvb of the first type
In the recording traces tva, tvb (recording traces by video information ... video track) sequentially formed on the magnetic tape T at the recording trace interval of Tp by the recording operation by, the rotary heads Haa, Hab of the second type are used. When an odd number of recording traces taa and tab (recording traces of audio information ... audio tracks) are formed by the recording operation, the recording traces of video information sequentially formed on the magnetic tape are always The recorded traces of the video signal in the odd field period and the recorded traces of the video signal in the even field period are sequentially adjacent to each other, and a reproduced image in a good interlaced scanning state can be easily obtained. To be

By the recording operation by the respective rotary heads of the first type, the second is formed in the recording traces tva and tvb (recording traces by video information ... video track) sequentially formed on the magnetic tape at the recording trace interval of Tp. When an even number of recording marks taa, tab (recording marks of audio information ... audio tracks) are formed by the recording operation by the rotary heads of the above type, the image information sequentially formed on the magnetic tape. The recording trace of is always the recording trace by the video signal in the odd field period (or the recording trace by the video signal in the even field period), but the so-called H / 2 (H is 1 horizontal scanning period) processing in the reproducing system. By providing the circuit, it is possible to easily obtain a reproduced image in a state in which the interlace scanning is favorably performed.

As an example, it is assumed that the video signal to be recorded / reproduced is configured according to the scanning standard for performing the interlaced scanning of 2: 1 at the vertical scanning frequency of 60 Hz, and the VHS (registered trademark) system is used. Tape speed (3.3) in standard play mode (SP mode) of VTR standard
(35 cm / sec), using a magnetic tape capable of recording and reproducing for 120 minutes, the SP mode of 3.335c
The tape speed of m / sec is set to 1/13, and the magnetic tape T is moved to 5 by the first type rotary magnetic heads Hva and Hvb.
When the video tracks tva and tvb having a track pitch of 8 μm (video track pitch) are formed, and the audio tracks taa and tab having a track width of 58 μm / 13 are formed by the second type rotary magnetic head, With a magnetic tape for 120 minutes, 26 hours of frame recording (60/13 frames per second) is performed and
Good audio signal recording is continuously performed over time.

As another example, it is assumed that the video signal to be recorded / reproduced is configured according to the scanning standard for performing the interlaced scanning of 2: 1 at the vertical scanning frequency of 60 Hz, and VHS (registered) is registered. A magnetic tape capable of recording / reproducing for 160 minutes at a tape speed (3.335 cm / sec) in a standard play mode (SP mode) in the VTR standard of the trademark system is used, and in the SP mode described above.
A track pitch (video track pitch) of 58 μm was formed on the magnetic tape by the first type rotating magnetic heads Hva and Hvb with the tape speed of 335 cm / sec being 1/9.
When the video tracks tva and tvb of No. 1 are formed, and when the audio tracks taa and tab having the track width of 58 μm / 9 are formed by the second type of rotary magnetic head, the magnetic tape for 160 minutes is used for 24 hours. In addition to the recording of frames (60/9 frames per second), a good audio signal is continuously recorded for 24 hours.

As still another example, a video signal to be recorded / reproduced has a vertical scanning frequency of 60 Hz and a video signal of 2 Hz.
The tape speed (about 1.112 cm / sec) in the extended play mode (EP mode) in the VHS (registered trademark) VTR standard is assumed to be configured according to a scanning standard for performing interlaced scanning on a one-to-one basis. A magnetic tape capable of recording / reproducing for 160 minutes is used, and the tape speed of about 1.112 cm / sec in the EP mode is set to 1/3, and the magnetic tape is formed by the first type rotary magnetic heads Hva and Hvb. Video tracks tva and tvb having a track pitch (video track pitch) of 19 μm are formed,
In addition, the rotary magnetic head of the second type produces 19 μm /
When audio tracks taa and tab having a track width of 3 are formed, a magnetic tape for 160 minutes is used for 24 tracks.
Recording of time frames is recorded (60/3 frames per second), and good audio signals are continuously recorded for 24 hours.

In the magnetic recording / reproducing apparatus described above, one rotary magnetic head is used as each of the first type rotary magnetic heads Hva and Hvb, but the present invention has been described. In carrying out the magnetic recording / reproducing apparatus of the present invention, as the first type of rotary magnetic heads Hva and Hvb, as shown in FIG. It is also possible to use a so-called double azimuth head in which the two are arranged close to each other. The rotary magnetic head Hv illustrated in FIG.
a is a rotary magnetic head Hva1 having a magnetic air gap of azimuth angle + α (for example +6 degrees) and a rotary magnetic head Hva2 having a magnetic air gap of azimuth angle -α (for example -6 degrees).
And 2 are arranged so as to be separated by a distance 2HL corresponding to the recording length of the video signal in the two horizontal scanning periods on the magnetic tape.

The rotary magnetic head Hvb illustrated in FIG. 6B includes a rotary magnetic head Hvb1 provided with a magnetic gap having an azimuth angle of -α (for example, -6 degrees) and an azimuth angle of +.
The rotary magnetic head Hvb2 provided with a magnetic gap of α (for example, +6 degrees) is arranged so as to be separated by a distance 2HL corresponding to the recording length of the video signal of two horizontal scanning periods on the magnetic tape. ing. The track width of the rotary magnetic heads Hva2 and Hvb2 is smaller than that of the rotary magnetic heads Hva1 and Hvb1 (for example, 1/3 of the tock width of the rotary magnetic heads Hva1 and Hvb1).

First type rotary magnetic heads Hva, Hv
When the so-called double azimuth head as described above is used as b, the rotary magnetic head Hva,
Even if the Hvb does not accurately track the video track to be reproduced, the signal level of the reproduced signal from the two rotary magnetic heads that are provided adjacent to each other in a pair By selecting the larger reproduction signal and using it as the reproduction signal, it is possible to output a reproduction signal capable of obtaining a good reproduction image.

That is, the recording traces by the rotation loci of two rotary magnetic heads having different azimuth angles are
In the magnetic recording / reproducing apparatus configured to sequentially and alternately form the magnetic tape T, the sequential recording marks recorded on the magnetic tape are alternately recorded by the rotating magnetic heads having different azimuth angles. When the magnetic head is set to perform reproduction while crossing, the video signal reproduced from the recording mark by the rotary magnetic head having the same azimuth angle as the rotary magnetic head used at the time of recording, and the rotation used at the time of recording. Only the reproduction signal in which the video signal reproduced from the recording mark by the rotary magnetic head having an azimuth angle different from the azimuth angle of the magnetic head is alternately arranged on the time axis is obtained.

However, assuming that the azimuth angle of the original magnetic air gap of one rotary magnetic head Hva is + α and the azimuth angle of the original magnetic air gap of the other rotary magnetic head Hvb is −α, As the rotary magnetic head Hva, the rotary magnetic head Hva1 having the original magnetic gap having the azimuth angle of + α and the rotary magnetic head Hva.
A small distance (eg 2
A rotary magnetic head Hva having a magnetic gap having an azimuth angle of -α at a position preceded by a distance 2HL) corresponding to a recording length of a video signal on a magnetic tape in a horizontal scanning period.
2 is used as a pair, and as the other rotary magnetic head Hvb, the rotary magnetic head Hvb1 having the azimuth angle of -α and the position of the magnetic gap of the rotary magnetic head Hvb1 are used. And a rotary magnetic head Hvb2 having a magnetic gap having an azimuth angle of + α at a position preceded by a small distance (for example, a distance 2HL corresponding to the recording length of a video signal in two horizontal scanning periods on a magnetic tape). By using the rotary magnetic head having a pair of the above-mentioned configurations, the signal having the larger reproduction output among the signals reproduced from the two magnetic gaps in each of the rotary magnetic heads described above is selected and used. Even when the rotary magnetic heads Hva and Hvb sometimes do not accurately track the video track to be reproduced, the rotary magnetic heads Hva and Hvb are installed adjacent to each other in pairs. Among the reproduction signals from the two rotating magnetic heads Hva1 and Hva2 (or Hvb1 and Hvb2) that are present, the reproduction signal with the higher signal level can be selected and the reproduction signal can be output. A reproduction signal capable of obtaining an image is obtained.

First type rotary magnetic heads Hva, Hv
As b, even when the so-called double azimuth head as described above is used, only two rotary magnetic heads Hva1 and Hvb1 provided symmetrically at 180 degrees are used for recording the frequency modulated wave signal by the video signal. Therefore, the recording operation is the same as the configuration operation of the recording system described above with reference to FIG. Further, regarding the recording and reproducing operations of the frequency-modulated wave signal by the audio signal by the rotary magnetic heads Haa and Hab of the second type, there is a difference from the recording and reproducing operation described above with reference to FIG. Absent. However, the first type of rotary magnetic head Hva,
When a reproducing operation is performed using the so-called double azimuth head as described above as Hvb, the reproducing operation from the recording mark recorded by using the rotating magnetic head Hva1 is performed by the pair of rotating magnetic heads. The reproducing operation from the recording traces performed by the heads Hva1 and Hva2 and recorded by using the rotary magnetic head Hvb1 is performed by the pair of rotary magnetic heads Hvb1 and Hvb2 and the pair 2 described above. Rotating magnetic head Hva
The configuration of the reproduction system is shown in FIG. 1 because it is necessary to select the reproduction signal having the larger signal level of the reproduction signal from 1, Hva2 (or Hvb1, Hvb2) to be the reproduction signal. It is different from the configuration mode.

That is, the first type rotary magnetic head H
As a reproduction system for a video signal when a so-called double azimuth head is used as va and Hvb, a reproduction signal from the rotary magnetic head Hva1 in the double azimuth head used as the first type rotary magnetic head Hva is recorded. A double azimuth which is supplied to the signal selection circuit 11 through the circuit of the movable contact v1 of the re-switching switch 21 → the fixed contact P1 → the preamplifier 9 → the signal selection circuit 11 and is also used as the first type rotary magnetic head Hvb. The reproduction signal from the rotary magnetic head Hvb1 in the head is changed from the movable contact v2 of the recording / reproduction changeover switch 21 to the fixed contact P2.
→ preamplifier 10 → supplied to the signal selection circuit 11 via the circuit of the signal selection circuit 11
The reproduction signal from the rotary magnetic head Hva2 in the double azimuth head used as the rotary magnetic head Hva of the type and the reproduction signal from the rotary magnetic head Hvb2 in the double azimuth head used as the first type of rotary magnetic head Hvb are also The recording / reproduction changeover switch 21 is provided with a movable contact and a fixed contact that are individually provided to a preamplifier that is individually provided, amplified there, and then supplied to the signal selection circuit 11. .

The rotary magnetic head Hva of the first type is also used.
Signal from the rotary magnetic head Hva1 and the rotary magnetic head Hv in the double azimuth head used as
Envelope detection is performed on each of the reproduced signals from a2 to obtain information on the signal levels of the two reproduced signals, and on the basis of the information on the signal levels of the reproduced signals, reproduction of the larger signal level is performed. A component for generating a signal that causes the signal to be selected by the signal selection circuit 11, and a rotary magnetic head Hv in a double azimuth head used as the first type rotary magnetic head Hvb.
Envelope detection is performed on the reproduced signal from b1 and the reproduced signal from the rotary magnetic head Hvb2 to obtain information on the signal levels of the two reproduced signals, and based on the information on the signal level of the reproduced signal. And a component for generating a signal that causes the reproduction signal having the higher signal level to be selected by the signal selection circuit 11,
It is added to the device shown in FIG.

The rotary magnetic head of the second type used in the construction of the magnetic recording / reproducing apparatus of the present invention has the first magnetic recording head formed prior to the formation of the recording mark by the rotary magnetic head of the first type.
It is possible to form n (where n is a natural number of 2 or more) recording traces in the recording traces sequentially formed on the magnetic tape at the recording trace interval of Tp by the rotary magnetic head of It suffices that the arrangement with respect to the first type rotary magnetic head is determined, and the arrangement relationship in the track width direction between the first type rotary magnetic head and the second type rotary magnetic head is shown in FIG. It is not limited to the state as illustrated in (b) of.

[Effects of the Invention] As is clear from the above description, the magnetic recording / reproducing apparatus of the present invention is
The magnetic tape wound obliquely around at least a part of the peripheral surface of the drum is continuously run at a constant running speed so that a predetermined recording mark interval Tp can be obtained. A predetermined number of rotations related to the vertical scanning period of the video signal to be recorded by the first type rotary magnetic heads having mutually different azimuth angles and provided at positions symmetrical by 180 degrees. And the recording traces of the video signal in the frequency-modulated wave form are sequentially formed at the recording trace intervals of Tp by the rotation locus of the rotary magnetic head of the first type. Prior to the formation of the recording traces (recording traces of image information) sequentially formed on the magnetic tape at the recording trace intervals of Tp by the rotation loci of the respective rotating magnetic heads, the respective rotating magnetisms of the first type described above are formed. In each recording trace (recording trace of video information) by the head, the frequency locus described above is generated by the rotation locus of the second type rotary magnetic head having an azimuth angle greatly different from that of the first type rotary magnetic head. Of modulated wave Recording traces of n (where n is a natural number of 2 or more) (recording traces of audio information) by a frequency-modulated wave type audio signal having an occupied frequency band in a lower frequency band than a lower part of the occupied frequency band of the image signal ) Is formed,
Recording information in n recording traces (recording traces of audio information) by audio signals in the form of frequency-modulated waves that are continuous on the time axis and recorded on the magnetic tape by the above-mentioned second type rotary magnetic head When a recording trace of a video signal is recorded and formed by a frequency-modulated wave of the video signal accompanied by the above-mentioned audio signal by the rotary magnetic head of the first type, a portion near the surface of the magnetic tape is The recorded magnetic tape in which the recorded information of the video information is recorded and the recorded information of the audio signal is deeply recorded is obtained, and the recorded magnetic tape described above is run at the time of recording. While the vehicle is running at a speed, the first type rotary magnetic head reproduces the frequency-modulated wave by the video signal, and the second rotary magnetic head reproduces the frequency-modulated wave by the audio signal. Then, for each of the above frequency-modulated waves, frequency demodulation is performed, and then predetermined signal processing is performed, so that a video signal in a frame-taken state and an audio signal in a continuous state on the time axis are obtained. Since it was made to reproduce, the video signal to be recorded and reproduced is
According to the present invention, the above-mentioned conventional problems can be solved satisfactorily, even if the frames are taken and recorded for a long time at a predetermined frame drop rate. it can.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of an example of a magnetic recording / reproducing apparatus of the present invention.

FIG. 2 is a diagram for explaining a rotary magnetic head.

FIG. 3 is an explanatory diagram of recording marks formed on a magnetic tape by a rotary magnetic head.

FIG. 4 is an explanatory diagram of recording marks formed on a magnetic tape by a rotary magnetic head.

FIG. 5 is a frequency allocation diagram of a recording signal.

FIG. 6 is a diagram for explaining a rotary magnetic head.

[Explanation of symbols]

5, 15 ... Frequency modulator, 6 ... Video signal selection circuit, 7,
8 ... Video information recording amplifier, 9, 10 ... Preamplifier, 11
... Signal selection circuit, 12, 18 ... Band pass filter, 13,
19 ... Frequency demodulator, 14 ... Reproduction video signal processing circuit, 1
7 ... Preamplifier, 20 ... Playback audio signal processing circuit, 21 ...
Recording / reproduction changeover switch, 23, 27, 33, 34 ... Changeover switch, 29 ... Capstan motor drive control circuit, 30 ...
Capstan motor, 31 ... Capstan FG signal generator, 35 ... Machine board, 36 ... Drum motor, 37 ... Drum F
G signal generator, 39, 40 ... Guide roller, 38 ... Drum rotation pulse (DFF signal) generator, 41, 42 ... Inclined pole, 43 ... Control head, 44 ... Capstan, 45 ... Pinch roller, 46 ... Pinch roller Bearing part, 38 ... Drum rotation pulse (DFF signal) generator, 4
3 ... control head, 44 ... capstan, DB ...
Drum base, Dd ... Fixed drum, Du ... Upper drum, T
... magnetic tape, Hva, Hvb ... first type rotary magnetic head, Haa, Hab ... second type rotary magnetic head, tva ... recording mark formed by rotary magnetic head Hva, tvb ... by rotary magnetic head Hvb Recording marks formed,

Claims (2)

[Claims] 1. A rotary locus of a rotary magnetic head of the first type, which has mutually different azimuth angles and is provided at 180-degree symmetry, causes an inclination on at least a part of the peripheral surface of the drum. In the wound state, a recording trace of the frequency modulated wave form video signal is recorded on the magnetic tape continuously running at a constant running speed so that a predetermined recording trace interval Tp is obtained. To form sequentially,
In addition, prior to the formation of the recording trace by each of the rotary magnetic heads of the first type described above, the magnetic tape has a lower frequency than the lower part in the occupied frequency band of the frequency modulated wave type video signal. Recording traces by a frequency-modulated wave type audio signal having an occupied frequency band in the band are sequentially recorded by a rotation locus of a second type rotary magnetic head having an azimuth angle greatly different from that of the first type magnetic head described above. In the magnetic recording / reproducing apparatus configured to be formed on the magnetic recording / reproducing apparatus, the recording operation is performed by the rotary heads of the first type described above, in the recording tracks sequentially formed on the magnetic tape at the recording track intervals of Tp. According to the recording operation by each rotary head of the second type,
Is a natural recording number of 2 or more). 2. A recording operation by each of the rotary heads of the second type described above in a recording track sequentially formed on a magnetic tape at a recording track interval of Tp by the recording operation by each rotary head of the first kind. The magnetic recording / reproducing apparatus according to claim 1, wherein an odd number of recording marks are formed by the above.