JPH05135432A - Magnetic tape, program searching device and program searching method - Google Patents

Abstract

PURPOSE:To provide a tape, a program searching device and a program searching method capable of high speed program searching and having advantage over the damage of the tape. CONSTITUTION:Index signals 11Ba, 11Bb and 13a are recorded in both the fixed track 10a and a helical track 13 of the tape 1. After fast-forwarding or rewinding the tape 1 and performing program searching at high speed by the index signals 11Ba and 11Bb recorded in the fixed track 10a, tape speed is set at normal speed and the program searching is accurately performed by the index signal 13a recorded in the helical track 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is, for example, a VTR, RD.
The present invention relates to a magnetic tape, a cueing device, and a cueing method that are suitable for use in the case of cueing a magnetic tape in an AT or the like.

[0002]

2. Description of the Related Art Conventionally, there is a β-max "index" (trademark) or the like which records an index signal on a control track (hereinafter referred to as a fixed track) and relies on the index signal to find the beginning of the tape. In these, since the index signal is recorded on the fixed track for a certain period of time, each program is cueed by detecting the index signal of the fixed track in one cassette tape.

However, in this method, the index signal is detected in the state where the cassette tape is fast-forwarded or rewound, and therefore the cueing accuracy is not good. 8 mmV there
In TR, index signals are recorded on the helical track to improve the cueing accuracy.

[0004]

However, when the index signal is recorded on the helical track as described above, although the cueing accuracy is improved, it is necessary to constantly apply the rotating drum to the tape, which is disadvantageous to the tape damage. Therefore, there is a problem in that the probability of reading the index signal decreases if the cue is performed at high speed.

The present invention has been made in view of such a situation, and provides a magnetic tape, a cueing device, and a cueing method, which can perform cueing at high speed and are advantageous in damaging a tape.

[0006]

In order to solve such a problem, a magnetic tape according to a first aspect of the present invention comprises a fixed track on which a cue index signal is recorded and a helical track on which a cue index signal is recorded. And a truck.

A cueing device according to a second aspect of the invention comprises a fixed track index signal recording / reproducing means for recording or reproducing a cueing index signal on a fixed track, and recording or reproducing a cueing index signal on a helical track. A helical track index signal recording / reproducing means.

A cueing method according to the third invention detects the index signal recorded on a fixed track by fast-forwarding or rewinding the magnetic tape, and then runs the magnetic tape at a slow speed to make a helical track. The feature is that the recorded index signal is detected to perform cueing.

[0009]

According to the first aspect of the present invention, the fixed track index signal and the helical track index signal are used for cueing.

According to a second aspect of the invention, the index is recorded and reproduced by the fixed track index recording and reproducing means and the index signal is recorded and reproduced by the helical track index signal recording and reproducing signal.

According to a third aspect of the invention, after the first cue is performed by the index signal recorded on the fixed track, the second cue is performed by the index signal recorded on the helical track.

[0012]

1 is a schematic diagram of a tape running system showing an embodiment of the present invention. In FIG. 1, the magnetic tape 1 passes through the path indicated by the symbol A when recording / reproducing at the normal speed. That is, S
(Supply) Reel 2a to Guide 3a, Tension Regulator 4a, Guide 3b, FE Head 5a, Guide 3c
To 3e, drum 6, guides 3f and 3g, A / C head (fixed head) 5b, guide 3h, capstan 7
It is wound on a T (winding) reel 2b via a and a guide 3i. During high-speed cueing such as fast-forwarding or rewinding, the tape is taken up from the S-reel 2a to the T-reel 2b via the guides 3j and 3k through the route of the symbol B.

In the apparatus constructed as described above, the present invention uses the index signals of both the fixed track and the helical track, and at the time of writing, after recording the index signal on the helical track, a certain time (corresponding to the free running distance) Min) later, write the rewinding index signal to the fixed track, rewind the magnetic tape at high speed at the time of cueing, stop the magnetic tape once when the index signal is detected by the fixed rack, and then slower than rewinding The magnetic tape is run at a speed (for example, a normal recording or reproducing speed), and an index signal is detected from the helical track to perform accurate cueing.

Writing of the video signal and the index signal to the helical track is performed by the rotary head mounted on the drum 6 along the path of symbol A, and the index signal to the fixed track is written by the A / C head 5b. Then, while the tape 1 is being cued to a predetermined place, first, the tape is traveled at a high speed until the A / C head 5b detects the index signal of the fixed track on the path of the symbol B where the winding angle is small and the traveling load is small. .. When the index signal of the fixed track is detected, the tape 1 is temporarily stopped, and then the operation of the loading drive system moves to the path of symbol A,
In order to perform accurate cueing by the index signal in the helical track using the drum 6, the vehicle travels at a normal traveling speed or a speed such as cue or review to search for a predetermined portion.

Recording of the index signal is performed as follows. Cue may be searched from the fast-forward direction or the rewind direction, and it is necessary to record each index signal on the fixed track. FIG. 2 shows the index signal recorded on the tape. For example, fixed tracks 10a and 10b are provided on the upper and lower ends of the tape 1, and the fixed track 10a has an index signal 11Ba for fast-forwarding and an index signal 11Bb for rewinding.
And the control signal 1 is recorded on the fixed track 10b.
Record 2. The index signal 13a for indexing for the helical track is recorded on the helical track 13.

As described above, the fast-forwarding or the rewinding of the tape is performed in the traveling path B shown in FIG. In addition, during fast forward or rewind, the index signal 11B
When a or 11Bb is detected, the tape 1 cannot be stopped instantaneously even if the tape 1 is controlled to stop running. That is, some free-running distance (overrun) occurs.

Now, assume that the tape 1 is stopped in the state of running B, and the virtual index signal 11Bx is at a position facing (detected) the A / C head 5b. In this state, when the traveling system is changed from the traveling route B position to the traveling route A position, the index signal 13a at the head of the helical track 13 comes to a position facing the rotary head 26 (FIG. 3) of the drum 6. To do.

The tape 1 is fast-forwarded or rewound during the traveling time B, and the virtual index signal 1 is sent by the A / C head 5b.
When 1Bx is detected, if the tape 1 can be suddenly stopped at that position, if the running distance is changed from B to A in that state, the index signal 13a is moved to a position facing the rotary head 26. It comes to the end (that is, the cue is completed). However, since the idling distance actually occurs, the index signal 11Ba for fast-forwarding is recorded by being shifted from the position of the virtual index signal 11Bx in the fast-forwarding direction by an amount corresponding to the idling distance L ₂ . Similarly, the index signal 11 for rewinding
Bb is recorded by shifting in an amount corresponding rewind direction corresponding to Sorahashi distance L ₃ from the position of the virtual index signal 11BX.

In this way, if the tape 1 is fast-forwarded in the traveling time B state and the tape 1 is stopped when the index signal 11Ba for fast-forwarding is detected by the A / C head 5b, the tape 1 is actually controlled. The tape 1 stops at a position where the virtual index signal 11Bx faces the A / C head 5b. Similarly, when the rewinding index signal 11Bb is detected by the A / C head 5b, the tape 1 is controlled to stop rewinding.
Indicates that the virtual index signal 11Bx is the A / C head 5b
It actually stops at the position facing. Therefore, when the tape running length is changed from B to A from this state, the index signal 13a of the helical track 13 comes to oppose the rotary head 26 of the drum 6.

When the user records the index signal for cueing, the following two cases can be considered. (A) When recording is started by pressing the record button on the VTR. (B) When reproducing a tape that has already been recorded and selecting a desired scene while viewing an image. Therefore, fixed track index signal 1 for rewinding direction
In either case, 1Bb is recorded after a certain period of time has elapsed after recording the index signal 13a for finding the helical track. This fixed time is a time corresponding to the idle running distance at the time of rewinding at the normal reproduction tape feeding speed, and this is managed by the system controller 20 (FIG. 3).

Further, the fixed track index signal 11Ba for fast-forwarding must be recorded prior to the index signal 13a for heading the helical track, and in both cases (a) and (b), during the rewinding operation. It is good to record. Specifically, when the user performs an eject or rewind operation after the operations of (a) and (b) above, the rewind operation is automatically performed and the fixed track index for the rewind direction already recorded. The signal 11Bb is detected, and the distance on the tape is calculated and recorded by the system controller 20 from the rewinding tape speed.

FIG. 3 is a block diagram showing an embodiment of the electric circuit of this apparatus. Record key 2 on controller 20
1, a playback key 22, an index key 23, a cue key 24, and a stop key 32 are connected. Then, the controller 20 operates the drive mechanism 25 according to the operation of these keys.
Is driven to rotate the rotary head 26 (drum 6), and at the time of recording, an index signal is supplied to the rotary head 26 via the index signal generation detection circuit 27a and the recording / reproducing circuit 28a. In addition, the index signal generation detection circuit 27
b, the fixed head 29 (see FIG. 1) via the recording / reproducing circuit 28b.
The index signal is supplied to the A / C head 5b). In addition, the fixed head 2 is connected via the recording / reproducing circuit 28c.
Control signal is supplied to 9.

During reproduction, the rotary head 26 and the fixed head 29
The signal detected in step 2
Is supplied to. The control signal waveform-shaped by the waveform shaping circuit 31 is supplied to the controller 20.

FIG. 4 is a flow chart showing the operation when the index key 23 is pressed in the reproduction mode. First, when the user presses the index key 23 (step 100), the controller 20 records the index signal 13a on the helical track 13 and, after a fixed time (corresponding to the idling distance), the fixed head 26 rewinds the fixed track 10a. The index signal 11b is recorded (step 101). This operation is repeated every time the index key 23 is pressed.

When the reproducing operation is stopped by depressing the stop key 32, the tape 1 is stopped and then reversed (step 103), and when the index signal 11Bb of the fixed rewinding track is detected, based on the control signal. Then, the vehicle is run for a certain distance and the index signal 11Ba of the fixed track for fast-forwarding is recorded (step 104). Then, the tape running is stopped (step 105).

FIG. 5 is a flowchart showing the cueing operation. When the user presses the cueing key 24 (step 15
0), and then fast-forwarding is performed along the route B in FIG. 1 (step 151). When the fast-forwarding index signal 11a of the fixed track is detected (step 152), the brake is applied to stop the tape running (step 153). ).
Then, the process moves to the route indicated by the symbol A in FIG. 1 (step 15
4), the tape is normally played back (step 155),
When the index signal 13a of the helical track is detected (step 156), the stop state or the pause state is set (step 157).

In the above, the index signals 11Ba and 11Bb are detected during the traveling time B, but it is also possible to detect the fixed track index signal during the traveling time A. In this case, when the fictitious index signal 11Ax faces the A / C head 5b during the traveling A, the first index signal 13a of the helical track 13 faces the rotary head. At this time, the distance L ₁₁ between the index signals 13a and 11Ax is longer than the distance L ₁ in the case of traveling B. The index signal 11Ab for the return index signal 11Aa and winding for fast forward is recorded by shifting by an amount corresponding virtual index signal 11Ax the fast forward direction or winding each air return direction run distance L ₁₂ or L ₁₃ It will be.

[0028]

As described above, according to the present invention, since the index signal is recorded on both the fixed track and the helical track, high-speed cueing is possible. Further, even if the cueing speed is increased, there is an effect that it is advantageous for tape damage.

[Brief description of drawings]

FIG. 1 is a diagram showing a tape traveling path of an apparatus to which the present invention is applied.

FIG. 2 is a diagram showing a relationship between a track recorded on a tape and an index signal.

FIG. 3 is a block diagram showing an embodiment of an electric circuit of an apparatus to which the present invention is applied.

FIG. 4 is a flowchart showing an operation when recording an index signal.

FIG. 5 is a flowchart showing an operation at the time of a cueing operation

[Explanation of symbols]

 1 Tape 2 Reel 3, 7 Guide 4 Tension Regulator 5b A / C Head 6 Drum 7 Capstan 8 Pinch Roller 10 Fixed Track 11 Index Signal 12 Control Signal 13 Helical Track 20 Controller 21 Recording Key 22 Playback Key 23 Index Key 24 Cue Key 25 Drive mechanism 26 Rotary head 27 Index generation detection circuit 28 Recording / reproducing circuit 29 Fixed head 31 Waveform shaping circuit

Claims (3)

[Claims] 1. A magnetic tape comprising: a fixed track on which a cue index signal is recorded; and a helical track on which a cue index signal is recorded. 2. A cueing device for detecting a desired magnetic tape position by detecting an index signal, and a fixed track index signal recording / reproducing means for recording or reproducing a cueing index signal on a fixed track. An index signal recording / reproducing device for a helical track, which records or reproduces an index signal for indexing to a helical track, and a cueing device. 3. A magnetic tape is fast forwarded or rewound to detect an index signal recorded on a fixed track, and then the magnetic tape is run at a slow speed to detect an index signal recorded on a helical track. A cueing method for a tape, which is characterized by performing a cueing.