JPH0646464B2 - Travel control method for magnetic tape - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling running of a magnetic tape, and particularly, when loosening of a magnetic tape occurs in a reel-to-reel direct drive magnetic tape device or the like, it is removed. The present invention relates to a magnetic tape running control method suitable for use in the above.

[Background of the Invention]

When the tape tension fluctuates due to winding looseness of the magnetic tape during the running control of the magnetic tape, for example, Japanese Patent Application No. 58-2361.
As proposed in Japanese Patent Laid-Open No. 60-129955, the magnetic tape is wound by detecting the fluctuation of tension and applying acceleration / deceleration torque to the supply reel and the take-up reel. Can be done. However, the method of accelerating and decelerating the reel described above is effective against loosening of the tape wound around the supply reel on the outer peripheral portion, but is sufficient for loosening of the inner peripheral portion of the tape. In some cases, the winding effect cannot be obtained.

[Object of the Invention]

The present invention has been made in view of the above problems, and an object of the present invention is to provide a running control method of a magnetic tape capable of reliably removing looseness of the inner peripheral portion of the supply reel.

[Outline of Invention]

In order to achieve the above object, in the magnetic tape running control method of the present invention, when the winding looseness cannot be removed even though the winding looseness of the magnetic tape is detected and winding is performed, the magnetic tape is removed. It is characterized in that the looseness of the tape is removed by running the tape in the forward direction once to the first position and then rewinding it to the second position again.

Example of Invention

Hereinafter, the present invention will be described in more detail with reference to the embodiments shown in the accompanying drawings.

FIG. 1 shows an embodiment in which the present invention is applied to a reel-to-reel direct drive magnetic tape device, and is a block diagram showing a tape running system of the reel-to-reel direct drive magnetic tape device. As shown in the figure, the magnetic tape 1 is fed from the supply reel 2,
The magnetic tape passes through the magnetic head 4 and the roller 5 and is wound on the winding reel 6. The roller 5 is provided with a speed detector 8 for detecting the tape speed, and the output speed signal is input to the take-up reel drive control circuit 9 and the supply reel drive control circuit 12. The roller 3 is a tension sensor that detects the tape tension. When the tension value exceeds the normal range, the tension detector 11 outputs a tension NG signal to drive the take-up reel drive control circuit 9 and the supply reel. Input to the control circuit 12. The take-up reel drive control circuit 9 and the supply reel drive control circuit 12 receive the speed signal and the tension NG signal, control the take-up reel drive motor 7 and the supply reel drive motor 10, and control the running of the magnetic tape 1. .

FIG. 2 is a flow chart showing an example of the operation of the embodiment shown in FIG. 1. In this operation example, loosening of the winding is detected during loading operation after the supply reel is loaded and before the start end marker (BOT) is positioned. To be done. That is, as shown in the figure, in step A, the magnetic tape 1 is accelerated in the forward direction until reaching a constant speed, and then decelerated for a constant time. During deceleration, it is determined whether the tension of the magnetic tape 1 exceeds the normal value range and the tension NG signal is output.

When it is determined that the tension NG signal has been output, it is determined whether or not the number of executions of step A has exceeded the specified number. If it is determined that the number of times has not exceeded the specified number, the supply reel drive motor 10 and the take-up reel drive motor 6 are controlled in order to apply appropriate acceleration / deceleration torque to the supply reel 2 and the take-up reel 6. Execute step A.
If it is determined that the specified number of times has been exceeded, step B is executed. In step B, the magnetic tape 1 is slowly accelerated in the forward direction to continuously run at high speed up to the edge marker (EOT), and then continuously run in reverse direction at high speed to rewind. Since starting and stopping are not performed in continuous running, slippage does not occur even in the winding loosening layer on the way, and tension fluctuation can be maintained within a normal value range. Therefore, EO
By rewinding from T, the magnetic tape 1 is rewound on the supply reel 2 with an appropriate tension, and the looseness is removed.

After the operation of step B is completed, the magnetic tape 1 is BOT
Positioned in. That is, the magnetic tape 1 is rewound to the BOT position. If the tension NG signal is not output after the execution of step A, the magnetic tape 1 is immediately attached to the BOT.

In addition, in the above-mentioned embodiment, in the step B, the EOT was continuously run in the forward direction, but the present invention is not limited to this, and the entire length of the magnetic tape is, for example, 2 minutes or 3 minutes. 2), the operation of step A shown in FIG. 2 is performed to determine whether or not the tension NG signal is output. If loosening is removed and the tension NG signal is not output, from this position. B
You may make it rewind to OT. This allows
The BOT positioning time, that is, the data processing start time can be reduced.

When the tension NG signal is generated during the normal data processing operation, the magnetic tape 1 is immediately stopped in the conventional manner to prevent data abnormality.

〔The invention's effect〕

According to the present invention, it is possible to reliably remove loosening of the winding generated in the inner peripheral portion of the supply reel, which cannot be dealt with by the conventional winding operation.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a flow chart showing an example of operation of the embodiment shown in FIG. 1 ... Magnetic tape, 2 ... Supply reel, 3, 5 ... Roller, 4 ... Magnetic head, 6 ... Take-up reel, 7 ... Take-up reel drive motor, 8 ... Speed detector, 9 ... … Take-up reel drive control circuit, 10 …… Supply reel drive motor, 11 ……
Tension detector, 12 ... Supply reel drive control circuit.

Claims (1)

[Claims] 1. A first step of accelerating and winding a magnetic tape wound on a supply reel onto a take-up reel until it reaches a first speed, and if the speed of the magnetic tape reaches the first speed. For example, a second step of detecting the tension of the magnetic tape by decelerating for a predetermined time, and a third step of determining whether or not the above two steps have been executed a prescribed number of times when the tension is inappropriate. If the third step is negative, a fourth step of changing the torques of the supply reel and the take-up reel to execute the first step, and the third step is positive. In one case, the magnetic tape wound on the supply reel is run to the take-up reel to a first position of the magnetic tape and then the magnetic tape is moved to a second position.
And a step of rewinding to the position.