JPS58111585A - Video tape recorder - Google Patents

Abstract

PURPOSE:To avoid the disturbance of reproduced picture at joints, by comparing the phase between a reproduced control and a synchronizing signal of a television signal to be recorded and controlling the phase of a capstan at the error signal. CONSTITUTION:A motor 7 driving a tape reel of a cassette 2 and a motor 6 of a capstan 4 are driven with a drive circuit 15 controlled with a microprocessor 9. At the pause mode, in the operation of the next recording, a tape 3 is run at a normal speed, and the phase between the control signal from the head 13 and the synchronizing signal of the television signal to be recorded next is compared and the phase of the capstan motor 6 is controlled with this error signal. When the number of the control pulse signals reproduced at the head 8 from the tape 3 reaches a prescribed number, the recording of the television signal to be recorded next and of the control signal is started.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a video tape recorder (hereinafter abbreviated as VTR), and is capable of making a transition between the previous recording and new recording even when a partially recorded video tape is reloaded into the VTR. This means that the reproduced image will not be disturbed at this seam, and therefore it is possible to continue recording by turning the power back on in a portable VTR. It is possible to reduce the consumption of

Conventionally, when a VTR temporarily stops the tape after recording halfway (pause state) and starts the next recording from this state, a control signal (so-called CTL The pulse intervals of the signal) are not necessarily at approximately equal intervals, and as a result, there is a drawback that synchronization disturbances occur on the reproduced screen.

As mentioned above, to eliminate such drawbacks,
When you perform an operation to temporarily stop the tape, the tape is rewound for a predetermined length and then stopped (pause state @). When the next recording operation is performed from this state, the tape will be stopped. The vehicle is run at a constant speed, and the previously recorded CTL signal is reproduced from the portion corresponding to the predetermined length that has been rewound.
The phase of the reproduced CTL signal and the synchronization signal of the television signal to be recorded next is compared, and the phase of the capstan for running the tape is controlled based on the error signal resulting from the comparison, so that the reproduction CTL signal and the synchronization signal are A device that keeps the phase relationship with the signal in a predetermined state and records the television signal on the tape from immediately before the point corresponding to the predetermined length (also records the CTL signal formed with the synchronization signal as a reference). Are known.

In this case, since the OTL signal is recorded as pulses at approximately equal intervals even at the seam, it is possible to eliminate synchronization disturbances in the reproduced image at the seam.

Incidentally, in the cassette VTR, in the above-described pause state, the only difference is that the tape does not run compared to the recording state, but the amplifier, motor, etc. are in an operating state, and the tape is in a loading state.

Further, in a case (cassette) VTR, when the power is cut off and the tape is stopped, the tape that has been pulled out of the cassette returns to the cassette, and the tape is unloaded.

Therefore, in order to record without causing the disturbance of the reproduced image at the seam mentioned above, it is necessary to enter a pause state at the recording seam.In a portable VTR, power is consumed even in this pause state. The drawback was that it consumed a lot of battery power. In order to reduce battery consumption, when the tape is stopped, the tape goes into an unloading state, and there is no guarantee that the position of the tape the next time it is loaded will match the position before unloading, and the image at the seam The hole problem remains unsolved. Furthermore, once the cassette is removed from the VTR,
Since the tape is loaded again in the next loading, there is no guarantee that the above-mentioned positions will match in this case as well.

The present invention eliminates the above-mentioned drawbacks. By pulling out the tape from the cassette and reloading it, the tape position (recording stop position) in the previous loading state and the tape position in the next loading state can be changed. position(
Even if the next recording position is different, the above-mentioned standby state can be obtained, and it is possible to prevent synchronization of the playback screen at the seam from occurring. Since the next recording can be continued from a stopped state, battery consumption can be reduced by applying it to a portable cassette VTR, and even if the cassette is removed from the VTR, the next recording can be continued. This provides a VTR that can perform

An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 shows a part of a VTR, and parts not directly related to the present invention are omitted.

In the figure, reference numeral 1 denotes a well-known head drum, and a tape 3 pulled out from a well-known cassette 2 is wrapped around the circumferential surface of the head drum, forming a so-called rope ink state. 4 is a capstan, and the tape is pressed against the capstan by a pinch roller 5 in a well-known manner. 6
7 is a drive motor for the capstan 4, 7 is a motor for driving the tape reel of the cassette 2, and 8 is a CTL head. Reference numeral 9 denotes a microcomputer, which includes a first timer 10, a second timer 1λ, a third timer 12, a counter 13, and a vagina counter zero detection circuit 14.
15 is a drive circuit for the motor 6.7, which is controlled by the microcomputer 9.

The operation of the VTR having the above configuration will be explained based on the flowchart shown in FIG.

First, when a search operation is performed in a stopped state, this is accepted (it is not accepted in any other state than the stopped state), a pause state is displayed, and the tape 3 is pulled out from the cassette 2 as is well known, as shown in FIG. A loading state is entered, and then, in response to a command from the microcomputer 9, the motors 6 and 7 run the tape 3 at a high speed, for example, 9 times the speed, using current from the drive circuit 15. On the other hand, upon completion of the above-mentioned loading, the timer lO is set to a sufficient time, for example, 0.3 seconds, to determine whether the CTL signal has not been recorded.
is the time to perform the search operation, for example 5.3 seconds (this is 1
(It may be set to a long time, such as minutes or more.) From the tape 3 which was played back at the above-mentioned 9x speed, the head 8
A TL signal may be regenerated. When this is regenerated, the timer 1 is activated for a short time equal to or longer than the CTL signal interval during high-speed driving.
For example, it is reset to 0°1 second, and is reset to 0.1 second by successive CTL signals.

After the timer 10 is set to 0.3 seconds and the loading is completed, if the CTL signal is not reproduced at all, that is, the unrecorded portion passes through the head 8 at 9x speed, the state without CTL pulse continues. are doing. When 0.3 seconds elapse in this state, the timer 10 goes over and the counter 3 is set to "60". the above. , within 3 seconds"'Q
When the C''TL signal is regenerated, it is determined that a CTL pulse is present, and the timer 10 is set to 0.1 seconds and is advanced by a set of 0.1 seconds with each successive OTL pulse. When 5.3 seconds have elapsed since 11 was set as described above, the timer 12 becomes over and the counter 13 is set to ``60''.

In many cases, the CTL pulse becomes "present" when the tape runs at 9x speed, and timer 1o is set to 0.1 seconds each time, and when an unrecorded part is reached in this state, the CTL pulse becomes "absent". , O seconds after the last CTL pulse, timer 1o goes over and counter 13 reads "
60”.

At the same time that the counter 13 is set to "60", the microcomputer 9 causes the motor 6.7 to move the tape 3 via the drive circuit 15 at a speed that is easier to control, for example, 3x speed. The third timer 12 is set to, for example, 2.3 seconds, which is longer than the time required to rewind 60 CTL at that speed. From tape 3 running at 3x speed in this way,
The CTL signal is reproduced by the head 8, and the counter 13 is counted down by the reproduced CTL pulse. As a result of this countdown, when the circuit 14 detects zero on the counter 13, an output is obtained at the terminal 16, and the tape enters a well-known pause state (standby state) where the tape stops running.

The third timer 12 rewinds at 3 times the speed, and when the counter 3 still does not reach zero even after 2.3 seconds have passed, or when an abnormality occurs, the third timer 12 outputs an output to the terminal 16 and enters a pause state. It is for use. In addition, when the timer 11 has an abnormality in which the CTL pulse does not become "absent" even after 5.3 seconds have elapsed as described above, the timer 10 indicates that the CTL pulse does not become "absent" even after 0.3 seconds have elapsed as described above. This is a safety feature that sets the counter 13 to "60" even in the event of an abnormality in which "Yes" does not occur.

Once the above-mentioned pause state is obtained, when the next recording operation is performed in this pause state in the same manner as explained in the conventional example (although the configuration etc. are omitted), the tape 3 will be recorded at the normal speed. The phase of the CT L signal from the head 13 and the synchronization signal of the television signal to be recorded next is compared, and this error signal causes the capstan motor 6 to
0 phase is controlled. When the number of CTL pulses reproduced by the head 8 from the tape 3 running at a normal speed reaches, for example, 50 pulses, recording of the television signal to be recorded and recording of the CTL signal are started. , it becomes possible to record without synchronization disturbance on the playback screen at the joint between this new recording and the previous recording.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing one embodiment of the present invention, and FIG.
A flowchart showing the operation of the one shown in the figure is shown.

Claims (1)

[Claims] When making a new recording following an already recorded part on a videotape, the tape should be The tape is rewound by a predetermined length and stopped, and the next recording operation causes the tape to run.The phase of the tape run is controlled by the control signal of the previous recording mentioned above, and a new signal is started from the time when the previous recording is approximately finished. In a video tape recorder configured to record data, a search operation causes the tape to run in the forward direction and a control signal is played back, and when it is detected that this playback control signal has disappeared for a predetermined period of time, the tape running direction is reversed. , regenerates the control signal while traveling in this reverse direction,
A video tape recorder characterized in that when the pulse of the reproduction control signal reaches a predetermined count value, the tape stops running and stands by in preparation for the next recording.