JPS63229656A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To perform patch recording and editing with a high precision by providing a buffer oscillator which oscillates while being locked to a reproduced control signal in the reproducing mode and being locked to the rotation phase signal of a capstan motor in the recording mode. CONSTITUTION:A buffer oscillator 17 is provided which oscillates while being locked to a reproduced control signal SCTL in the reproducing mode of patch recording and editing and being locked to a rotation phase signal SPG of the capstan motor in the recording mode, and an oscillation output SOSC of the buffer oscillator 17 is used as a comparison signal STP to be compared with a reference signal SV of a capstan servo or a recording control signal. Consequently, in case of patch recording and editing where the mode is switched from the reproducing mode to the recording mode, the buffer oscillator 17 is allowed to oscillate at the same timing as the reproduced control signal continuously in the recording mode. Thus, servo disturbance at joints (editing points) and discontinuity of the control signal on a control track are prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic recording/reproducing apparatus having a continuous shooting/editing function.

2. Description of the Related Art A conventional example of continuous shooting editing in a magnetic recording/reproducing apparatus (hereinafter referred to as VTR) is Japanese Patent Publication No. 18805/1983. FIG. 7 is a block diagram of such a conventional device,
FIG. 8 is a diagram of its operating waveforms. In Fig. 7, 1 is a magnetic tape, 2 is a capstan, 3 is a pinch roller, and 4 is a magnetic tape.
is a control head, 5 is a capstan motor, 6 is a rotation detector, 7 is a speed control means, 8 is a frequency dividing means, 9゜1
0 is the first. In the second switch, 11 is a recording means, 12 is a phase adjustment means, 13 is a phase control means, 14 is a mode switching signal input terminal, and 16 is a reference signal input terminal.

As is well known, the magnetic tape 1 is transported by a capstan 2 and a pinch roller 3, and the capstan 2 is driven by a capstan motor 5. The capstan motor 6 is provided with a rotation detector (generally referred to as a frequency generator, hereinafter referred to as FC1) θ for detecting the rotation speed, and an FG multiplied signal FG as shown in FIG. 8G obtained from this is provided. The frequency of the capstan motor 5 is discriminated by the speed control means 7, and the speed of the capstan motor 5 is controlled by the discrimination output so that the rotational speed of the capstan motor 5 is constant.

On the other hand, the phase control means 13 has different roles in the recording mode and the reproduction mode, and in the recording mode, the capstan motor 5
The magnetic tape 1 is used to accurately control the number of rotations of the magnetic tape 1, and enables highly accurate transfer of the magnetic tape 1. In the playback mode, tracking controls are provided to allow a video head (not shown) to accurately trace the video track.

A mode switching signal SMO as shown in FIG. 8 is input to the input terminal 14, and the first . The second switch 9.10 is connected to the R side in storage mode and to the P side in playback mode.

A vertical synchronizing signal Sv having a frame frequency (30 Hz) as shown in FIG. 8B is input to the input terminal 15, and is used as a reference signal for the phase control means 13 and is also supplied to the recording means 11 as a recording control signal. The output of the recording means 11 is supplied to the control head 4 via the first switch 9 and recorded on the control track of the magnetic tape 1 as a control signal.

The FG multiplied signal rc is supplied to the frequency dividing means 8, and the rotating phase signal S as shown in FIG.
pa (hereinafter referred to as PG times signal).

P(r signal ppc is supplied to the phase adjustment means 12 via the second switch 1o, and the time T, as shown in FIG. 8E,
The phase control means 13 outputs a signal SτP delayed by
It is used as a comparison signal. In the phase control means 13, the reference signal S
v, a trapezoidal wave having a slope for phase comparison as shown in FIG. 8C is formed, and the phase comparison is performed by sampling with the comparison signal STP. and,
The phase comparison output is supplied to the speed control means 7 and mixed with the frequency discrimination output to control the rotational phase of the capstan motor 5. Thereby, the capstan motor 5 can be quartz-locked to the reference signal Sv.

The above is the operation in recording mode. In the playback mode, a playback control signal 5CTL as shown in Figure 8, which is played back from the magnetic tape 1 by the control head 4, is obtained via the first switch 9.
The positive pulse of rt is used as a reset signal for the frequency dividing means 8 and is also input to the phase adjusting means 12 via the second switch 1o. This causes the playback control signal 5CTL to change to the time T.

Since the output STP whose phase has been adjusted by 1 is obtained from the phase adjustment means 12, tracking control of the magnetic tape 1 can be performed by comparing the phase of this signal STP and the reference signal Sv. That is, the tracking position can be adjusted by the phase adjustment means 12.

The above enables normal recording and playback on a VTR.

When performing splicing editing, the magnetic tape 1 is rewound by a predetermined amount, and a switching operation is performed in which the magnetic tape 1 is moved through the playback mode and then into the recording mode. With this switching, the second switch outputs the playback control signal 5CTL in the playback mode.
Since the recording mode is switched to select the PG doubler SPG, if the phases of the reproduction control signal 5CTL and the PG doubler SPG are not approximately equal, step-out occurs in the phase control means 13 and servo disturbance occurs. In this case, there is a problem that continuity of the recording pattern at the seam cannot be obtained, and the reproduced image in the reproduction mode is disturbed. In the conventional example, this problem was solved by an extremely simple configuration in which the frequency dividing means 8 was reset by the reproduction control signal 5CTL. If such a reset means is used and the FG double signal sra is set to a sufficiently higher frequency than the reproduction control signal ScτL, the reproduction control signal SCτ
By taking out the FG double trust SFG immediately after L, the PG double trust spa can be obtained. At that time, the phase difference between spG and SCτL is less than one period of the FG doubler SFG, and servo disturbance can be suppressed to a small level.

Problems to be Solved by the Invention However, with the above configuration, it is not possible to prevent servo disturbance corresponding to one cycle of the FG doubler src.
In addition, if the frequency dividing means 8 is configured not to be reset by the reproduction control signal 5cTt, the effect can no longer be obtained. In addition, when using the reference signal Sv as a recording control signal, the timing (positive pulse) of the reproduction control signal 5cTt as shown in Figure 8
must match the rise of the reference signal Sv, and it is necessary to fix the adjustment amount TP of the phase adjustment means 12 so that the above relationship is obtained. For this reason, there is no problem with self-recording and playback, but when considering compatibility between VTRs, it is necessary to
Or, even if you want to shift the timing in the direction of (b), you cannot shift the timing, and the recording pattern at the seam ends up being discontinuous. There were other problems.

Means for Solving the Problems The present invention locks to the playback control signal in the playback mode of spliced editing, which transitions from the playback mode to the record mode, and locks to the rotational phase signal of the capstan motor in the record mode to oscillate. The present invention is a magnetic recording/reproducing device that uses an oscillation output of the buffer oscillator as a comparison signal with respect to a reference signal of a capstan servo, as a recording control signal, or as a comparison signal and a recording control signal.

The present invention also includes a buffer oscillator that locks to a playback control signal in playback mode and oscillates while locking to a vertical synchronization signal that becomes a capstan servo reference signal in record mode, and records and controls the oscillation output of the buffer oscillator. This is a magnetic recording and reproducing device that uses signals as signals.

The present invention also includes a first buffer oscillator that locks to a playback control signal in a playback mode and oscillates while locking to a rotational phase signal of a capstan motor in a record mode;
a second buffer oscillator that locks to the playback control signal in the playback mode and oscillates while locking to the vertical synchronization signal that becomes the capstan servo reference signal in the record mode; The present invention is a magnetic recording/reproducing device in which a comparison signal with respect to a capstan servo reference signal is used, and an oscillation output of the second buffer oscillator is used as a recording control signal.

Effect of the Invention With the above-described configuration, the present invention allows the buffer oscillator to continue to oscillate at the same timing as the playback control signal even in the recording mode when performing splicing editing to transition from the playback mode to the record mode. (It is possible to prevent servo disturbance at the editing point and discontinuity of the control signal on the control track. This makes it possible to eliminate discontinuity in the recording pattern and obtain a stable reproduced image.

Embodiment FIG. 1 is a block diagram of a magnetic recording/reproducing apparatus according to a first embodiment of the present invention, and FIG. 2 is an operational waveform diagram of the same embodiment. Components 1 to a in FIG.

9 and 11 to 15 are the same as those in the conventional example shown in FIG. 7, so their explanation will be omitted. 16 is a rotational phase detector (PC) that detects the rotational phase signal spG of the capstan motor 5; 17
is a buffer oscillator.

In Figure 1, PG double SP obtained from PGl 6
G is within plus or minus A period with respect to the playback control signal 5cTt (±1/fCTL: fCTL
is the frequency of the playback control signal 5CTL, and 30
It has a phase difference of PG double trust sp like this
a, the playback control signal 5cT in the playback mode.
If the recording mode is switched from t to PG double feed spa, the capstan servo will be disturbed, making it impossible to perform stable editing. This is a conventionally known problem, and an example of its countermeasure is the conventional example shown in FIG. That is, in the conventional example, the phase difference between the reproduction control signal 5CTL and the PG doubler spG is set to V.
We are pushing it within fra.

The present invention implements a solution to the above problem by using a buffer oscillator 17, so that stable editing can be performed regardless of the phase of the PG doubler spG.

The operation of the buffer oscillator 17, which is the main part of the present invention, during editing will be explained below using the waveform diagram shown in FIG.

The buffer oscillator 17 is implemented as a counter and performs an oscillation operation as shown in FIG. 2F. Figure 2 G is the pulse SNF obtained by decoding the predetermined count value NF of the counter.
This pulse is used as a feedback pulse for presetting the counter.

That is, the initial value NP is preset in the counter by the feedback pulse say. In this way, the oscillation operation shown in FIG. 2F can be obtained by the counter, and the oscillation output 5 osc shown in FIG. 2 can be obtained.

In the playback mode, the counter of this oscillator 17 is added to the feedback pulse snr to generate the playback control signal 5C.
Preset to NPo with positive pulse of TL. Then, at the rising edge of the PG doubler SPG shown in FIG. 2H, the counter's mid-count value Nx is stored in the memory. Next, in the recording mode, since the reproduction control signal 5CTL disappears, the counter is preset to NPo by the feedback pulse 5rtr. Then, at the rising edge of the PG doubler SPG in FIG. 2H, the output Nx of the memory is preset in the counter.

If the buffer oscillator 17 is configured as described above, the output timing of the oscillation output 5osc will not be disturbed even when switching from the reproduction mode to the recording mode.

However, in the capstan servo during editing, the phase adjustment means 12 always receives the oscillation output 5osc of the buffer oscillator 17.
By adopting a configuration in which the phase-adjusted comparison signal STP is inputted, the phase-adjusted comparison signal STP can be kept in a constant phase relationship with the reference signal Sv, and servo disturbances will not occur.

In addition, the oscillation output 5osc is the reproduction control signal 5cT.
Since the signal has the same timing as t, it can be input to the recording means 11 and used as a recording control signal in the recording mode.

As is clear from the above description, in the VTR of the present invention, a continuous recording pattern can be formed without disturbance of the capstan servo or discontinuity of the control signal on the control track during splicing editing. , and a stable reproduced image can be obtained.

FIG. 3 is a block diagram showing a specific example of the configuration of the buffer oscillator 17, which is the main part of the present invention, and FIG. 4 is a waveform diagram for explaining the operation of the same figure. In FIG. 3, 100 is a timing pulse generation section, 101 is a counter section, 102 is a memory section, 103 is a switch section, 104 is a preset value generation section, 106 to 108 are input terminals, and 109 is an output terminal.

The timing pulse generator 100 has input terminals 105 to 1.
08 to PC signal SPG, mode switching signal 5M09
Playback control signal 5CTL + clock pulse S
c, and also input the feedback pulse SNF emitted from the counter section 1o1, preset pulse SP, latch pulse SL, data switching signal 3. Create and output. The timing pulse generator 1oO uses the clock pulse ScK to change the output from the positive pulse of the reproduction control signal 5crt shown in FIG. 4B to the clock pulse C in FIG.
The pulse P1 shown in FIG. 1 is generated from the rising edge of the PG doubler spG shown in FIG. F, and the pulse P2 shown in FIG. In the playback mode in which the mode switching signal SMo is L'', the feedback pulse SNF and pulse P shown in FIG.
The preset pulse SP is shown in the same figure, and the pulse P
2 is the latch pulse SL shown in FIG. In the recording mode where the mode switching signal SMO is "Hu", the feedback pulse SNF pulse P2 is set as the reset pulse S, and the latch pulse SL is not output. In addition, the data switching signal Sw shown in the drawing is a feedback pulse 5rt.
"H" immediately after r and pal 22 (or "L" immediately before)
Otherwise, it is formed as a signal that becomes "L" immediately after pulse P2 (or becomes H immediately before pulse P2).

The thus obtained puIJ4tbars S.

The latch pulse SL and the data switching signal S are sent to the counter section 1o1. Memory section 1o2. The signal is supplied to the switch section 103. Then, a clock pulse SGK is supplied to the counter section 101 to enable counting operation, and when the data switching signal Sw is "L", the preset value generating section 101
When the output NPo of 04 is ``H++, the memory unit 102
The output Nx is supplied as a preset value via the switch section 103.

As a result, in the reproduction mode, the counter section 101 performs a counting operation with NPo preset by the preset pulse SP, and stores the intermediate count value Nx of the counter section 101 in the memory section 102 by the latch pulse SL. In the recording mode, the memory section 102 stores and holds the data Nx at the end of the playback mode, so the data switching signal S and the NPo and Nx selectively output from the switch section 103 are preset in the counter section 101. counting operation.

As described above, the oscillation output 5osc shown in FIG. 4K is obtained from the counter section 101. This oscillation output 5osc is the playback control signal Stl:TL in the playback mode.
, and continues to be synchronized even after switching to recording mode. Therefore, by using this oscillation output 5 osc as a capstan servo comparison signal or as a recording control signal in the present invention, stable and accurate continuous shooting 9 editing can be performed.

Further, in the present invention, since the buffer oscillator can be operated using the clock pulse SCK, its frequency can be set extremely high, and the phase difference between the reproduction control signal 5CTL and the oscillation output 5osc can be within 1 clock. Highly accurate editing is possible.

FIG. 5 is a block diagram of a magnetic recording/reproducing apparatus according to a second embodiment of the present invention, and FIG. 5 is an operational waveform diagram of the same embodiment. The difference between the second embodiment and the first embodiment is that the buffer oscillator 17 is a first buffer oscillator, and its oscillation output 5
osc+ is dedicated to the capstan servo comparison signal,
The point is that a second buffer oscillator 18 dedicated to newly forming a recording control signal is provided. Below, the second
Only the operation of the buffer oscillator 18 will be explained with reference to the waveform diagram of FIG.

A buffer oscillator having the configuration shown in FIG. 3 can also be used as the second buffer oscillator 18.

In this case, it is only necessary to input the reference signal Sv to the input terminal 106 instead of the PG doubler SPG.

That is, the difference between the first buffer oscillator 17 and the second buffer oscillator 18 is whether the PC signal SPG or the reference signal Sv is used.

In the playback mode, the initial value HPo is preset using the positive pulse of the playback control signal 5CTL shown in FIG. At the rising edge of the reference signal Sv shown in FIG.
is stored in memory.

On the other hand, in the recording mode, the playback control signal is 5ctt.

disappears, the counter is preset to NPo by feedback pulse 5NF2. And the reference signal S
At the rising edge of v, the memory output Nx is preset to the counter. If the second buffer oscillator 18 is configured as described above, the output timing of the oscillation output 5Oi9C2 shown in FIG. Thereby, the recording control signal can be formed from the reference signal noodle, and it can be a signal with less time axis fluctuation compared to the oscillation output 5osc2 created from the PG double signal spa.

In addition, 1. In the second embodiment, a configuration using PCl3 to obtain the PG doubler spG was shown, but the PG 16
It goes without saying that FGe can also be used for the same purpose, and in this case, the FC signal SFG can be simply stepped down to a frequency of 30) to form the pc signal SPG. That is, there is no need for a reset operation as in the conventional example.

As described in detail, according to the present invention, the phase relationship between the reproduction control signal 5CTL and PC and the signal SPG and the phase relationship between the reproduction control signal 5CTL and the reference signal Sv can be ignored, and Highly accurate splicing editing is possible. In addition, since it can be implemented entirely with digital circuits, it is advantageous for IC implementation, and has great practical effects.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a magnetic recording and reproducing apparatus according to a first embodiment of the present invention, FIG. 2 is an operating waveform diagram of the same embodiment, and FIG.
The figure is a block diagram showing a specific example of the configuration of the buffer oscillator which constitutes the main part of the present invention, Figure 4 is an operation waveform diagram of the example of the configuration, and Figure 5 is a diagram of the magnetic recording/reproducing apparatus according to the second embodiment of the present invention. FIG. 5 is an operational waveform diagram of the same embodiment, FIG. 7 is a block diagram of a conventional magnetic recording/reproducing apparatus, and FIG. 8 is an operational waveform diagram of the conventional example. 1... Magnetic tape, 2... Capstan, 4... Control head, 5...
Gear, Fustan motor, 6...FG, 7...
... Speed control means, 9 ... First switch, 11 ... Recording means, 12 ... Phase adjustment means, 13 ... Phase control means , 16...
PG, 17...Buffer oscillator or first buffer oscillator, 18...Second buffer oscillator, 100...Timing pulse generator, 10
1... Counter section, 1o2... Memory section, 103... Switch section, 104...
・Preset value generation section. Name of agent: Patent attorney Toshio Nakao and 1 other person: Illness 1
Figure 2 Figure 3 5ysc Figure 5 + 4 Figure 6

Claims (6)

[Claims] (1) A buffer oscillator is provided, which locks to the playback control signal in the playback mode of splicing editing that transitions to the record mode after the playback mode, and locks to the rotational phase signal of the capstan motor to oscillate in the record mode; A magnetic recording/reproducing device characterized in that the oscillation output of the capstan servo is used as a comparison signal with respect to a reference signal of a capstan servo, or as a recording control signal, or as a comparison signal and a recording control signal. (2) In the playback mode, the oscillation output of the buffer oscillator is locked to approximately the same timing as the playback control signal, and the internal state of the oscillator is stored in the memory using the rotational phase signal, and in the recording mode, the rotational phase signal is used to store the internal state of the oscillator in the memory. 2. The magnetic recording and reproducing apparatus according to claim 1, wherein the oscillator is loaded with the output of a memory and locked. (3) Equipped with a buffer oscillator that oscillates by locking to the playback control signal in the playback mode of spliced editing that transitions from the playback mode to the record mode, and in the record mode to the vertical synchronization signal that becomes the reference signal for the capstan servo. , A magnetic recording/reproducing apparatus characterized in that the oscillation output of the buffer oscillator is used as a recording control signal. (4) In the playback mode, the oscillation output of the buffer oscillator is locked to approximately the same timing as the playback control signal, and the internal state of the oscillator is stored in the memory using the vertical synchronization signal, and in the recording mode, the vertical synchronization signal is used to store the internal state of the oscillator in the memory. 4. The magnetic recording and reproducing apparatus according to claim 3, wherein the output of the memory is loaded into the oscillator and locked. (5) A first buffer oscillator that locks to the playback control signal in the playback mode of spliced editing that transitions from the playback mode to the record mode, and that oscillates while locking to the rotational phase signal of the capstan motor in the record mode; a second buffer oscillator that locks to the playback control signal in the mode and oscillates while locking to the vertical synchronization signal that becomes the reference signal for the capstan servo in the recording mode; A magnetic recording/reproducing device characterized in that a reference signal of a stun servo is used as a comparison signal, and an oscillation output of the second buffer oscillator is used as a recording control signal. (6) In the playback mode, the oscillation output of the first buffer oscillator is locked to substantially the same timing as the playback control signal, and the internal state of the first oscillator is stored in a first memory using a rotational phase signal; In the recording mode, the output of the first memory is loaded and locked into the first oscillator by the rotational phase signal, and in the playback mode, the oscillation output of the second buffer oscillator is at approximately the same timing as the playback control signal. and storing the internal state of the second oscillator in a second memory using a vertical synchronization signal, and in a recording mode, loading the output of the second memory into the second oscillator using the vertical synchronization signal. 6. The magnetic recording and reproducing apparatus according to claim 5, characterized in that the magnetic recording and reproducing apparatus is configured to be locked.