JPH03242846A - Detection of loosened winding of magnetic tape for magnetic tape device - Google Patents

Abstract

PURPOSE:To eliminate the influence on the traveling operation of a magnetic tape by detecting the loosening in winding of the magnetic tape in the process of mounting a cartridge before the start of recording/reproducing of information to and from the magnetic tape. CONSTITUTION:The single reel type cartridge tape is mounted on a magnetic tape device and the tape reel in the cartridge 1 is coupled to a reel motor 5. The reel motor 5 is rotationally driven by a motor driving control circuit 9 and the torque in the rewinding direction of the tape is gradually increased up to the max. torque at which the tape is not damaged to tighten the winding of the tape. The rotating quantity of the tape reel is measured by a tachometer 6 and the output pulses are inputted to a tachometer pulse counter 10 of a rotating pulse integrating circuit 7, by which the pulses are counted and the quantity of the loosening in winding of the tape is detected. The operation to eliminate the loosening in winding or the stop of loading is executed in this way and the influence on the traveling operation of the magnetic tape is eliminated.

Description

[Detailed description of the invention] [Table of contents] Overview Industrial field of application Prior art (Figure 7) Means for solving the problems to be solved by the invention (Figure 1) Working examples (Figure 2) - Figure 6) Effects of the invention [Summary] Regarding the method for detecting looseness in the winding of a magnetic tape in a magnetic tape device, the looseness of the winding of the magnetic tape is detected in the process of installing a cartridge before starting recording/reproducing information on the magnetic tape. The purpose of this system is to perform operations such as eliminating loose winding or canceling loading by detecting this, so that the running operation of the magnetic tape is not affected at all. As a pre-processing step before the tape transfer operation during recording/playback, the amount of loose winding of the tape loaded in the magnetic tape device is detected, and depending on the detected value, it is possible to eliminate the loose winding or perform abnormality recovery processing. In the method for detecting tape winding slack in a magnetic tape device, the installed cartridge tape is rotated in the tape rewinding direction with a weak torque to remove tape slack, and then the tape is rotated in the tape rewinding direction. The tape is tightened by gradually increasing the torque of the tape to the maximum torque that does not damage the tape, and the amount of loosening of the tape is detected by observing the amount of rotation of the tape reel during tightening. .

[Industrial application field]

The present invention relates to a method for detecting winding looseness of a magnetic tape in a magnetic tape device, and more specifically, the present invention is used in a magnetic tape device using a single-reel cartridge tape. The present invention relates to a method for detecting winding slack of a magnetic tape in a magnetic tape device, which prevents the running operation of the magnetic tape from being affected by detecting and dealing with the amount of tape winding slack.

[Conventional technology]

In a conventional magnetic tape device that uses a single-reel cartridge tape as a recording medium, before recording/reproducing information on the magnetic tape while running it, the magnetic tape is first guided through a tape mounting device. Must be attached to the mechanism. For this purpose, a cartridge mounting and fixing mechanism is provided.

Next, the magnetic tape is pulled out from the installed cartridge, passes through a tape running guide mechanism, and is wound onto a take-up roll. In this way, the running operation of the magnetic tape becomes possible.

In the above case, the process from mounting the cartridge to preparing for tape transfer is called tape loading. After the tape is loaded, the tape is transferred by direct drive between the feed reel and take-up reel, and there is no buffer mechanism between them.

In addition, in normal cases, with the magnetic tape stretched between the reels, the amount of tape wound on both reels is measured, and the two reel motors are servo-controlled accordingly to keep the tape running speed and tension constant. It's in control.

FIG. 7 is a schematic diagram (plan view) of the single reel type cartridge tape as described above, and in the figure, 1 is a cartridge, 2 is a magnetic tape, 3 is a league block, and 4 is a rotating shaft.

This tape has a rotating shaft (can be rotated only when attached to the device)
A league block (for example, a resin block) 3 connected to the starting end of the magnetic tape is provided at the externally drawn end.

The league block 3 is fixed to the cartridge 1 at a predetermined position, and is a tapered block (or a block with a stopper) so as not to be drawn into the inside of the cartridge 1.

[Problem to be solved by the invention]

The above-mentioned conventional devices had the following drawbacks.

+1) When the temperature of the cartridge drops, the winding becomes loose due to the effect of thermal contraction of the magnetic tape, reel resin, or air trapped between the tape winding layers.

In addition, the winding may become loose due to vibration during storage or transportation.

(2) If the tape is run with loose tape winding, it will become impossible to keep the tape tensioned between the reels at the specified tension due to the looseness, and the rotational relationship between the reels will be disrupted, causing the tape to wind. If the quantity is measured incorrectly, servo control becomes completely impossible.

(3) If servo control becomes impossible, it becomes impossible to run the magnetic tape at a constant speed and tension, and information may not be recorded properly on the medium, or the medium may be damaged. Put it away.

(4) On the other hand, it is possible to always rewind the loaded tape to avoid being affected by loose winding, but if you do this, it will always take a long time to start recording and playing information after loading. It takes.

Therefore, the processing capacity of this device will be reduced.

The present invention eliminates these conventional drawbacks and eliminates the loosening of the magnetic tape by detecting the loosening of the magnetic tape during the process of installing a cartridge before starting recording/reproducing information on the magnetic tape. The purpose of this is to stop the operation or load so as not to affect the running operation of the magnetic tape at all.

[Means to solve the problem]

FIG. 1 is a diagram showing the principle of the present invention, FIG. A is a flowchart of the principle of a winding slack detection method, and FIG. 1 is a block diagram of the principle of a magnetic tape control device.

In the figure, the same symbols as in FIG. 7 indicate the same parts, 5 is the reel motor, 6 is the tachometer, 7 is the rotation pulse integration circuit, and 8 is the reel motor.
Reference numeral denotes a slack amount determination circuit, 9 a motor drive control circuit, 10 a tachometer pulse counter, 11 a comparator, 12 a slack amount determination table, and 13 a selector. Note that each processing number shown in Figure B is shown in parentheses.

In order to achieve the above object, the present invention detects the amount of slack in the winding of a tape loaded in a magnetic tape device as a pre-processing of a tape transfer operation when recording/reproducing information using a single reel cartridge tape. In a method for detecting loose winding of a magnetic tape in a magnetic tape device, the loose winding of a magnetic tape can be detected, and an action to eliminate the loose winding or an abnormality recovery process can be executed according to the detected value, the tape is wound with a weak torque on the mounted cartridge tape. The tape is rotated in the rewinding direction to remove slack (100), and then the tape is tightened by gradually increasing the torque in the tape rewinding direction to the maximum torque that does not damage the tape. By observing the amount of rotation of the tape reel inside, the amount of tape winding loosening is detected (101).

[Effect]

Since the present invention is configured as described above, it has the following effects.

First, a single reel type cartridge tape is loaded into a magnetic tape device, and the tape reel inside the cartridge 1 is connected to the reel motor 5.

In this state, the motor drive control circuit 9 rotates the mounted cartridge tape in the rewinding direction with a weak torque to remove slack in the tape (100). Additionally, the tachometer pulse counter lO is cleared and initialized.

Next, the reel motor 5 is rotationally driven by the motor drive control circuit 9, and the tape is wound tightly by gradually increasing the torque in the tape rewinding direction to the maximum torque that does not damage the tape.

At this time, the amount of tape reel rotation is measured by the tachometer 6, and the output pulses are input to the tachometer pulse counter IO of the rotational pulse integration circuit 7 and counted, thereby detecting the amount of tape winding loosening (101).

Thereafter, the count value of the tachometer pulse counter 10 is input to the comparator 11 of the slack amount determination circuit 8. Further, one of the reference values (normal reference value or excessive reference value) selected by the selector 13 is input to this comparator in response to a selection signal from the motor drive control circuit 9, and the two are compared.

The comparison result is sent to the loosening amount determination table 12, and a predetermined table is referred to to output a countermeasure according to the amount of loosening.

That is, if the tape is extremely loose (102), the loading should be stopped and the cartridge should be ejected (104), and if it is slightly loose (103), the cartridge should be re-wound (105).
, otherwise the loading operation is continued because it is normal (106).

In this way, it is possible to automatically detect tape winding loosening and perform an operation such as stopping loading or eliminating loosening (rewinding).Therefore, the running operation of the magnetic tape is not affected.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

2 to 6 are diagrams showing one embodiment of the present invention. FIG. 2 is a block diagram of a magnetic tape control device, and FIG. 3 is a block diagram of a magnetic tape control device.
The figure is a partial detailed view of the magnetic tape control device shown in FIG. 2, FIG. 4 is a processing flowchart of the embodiment, and FIG.
FIG. 6 is an explanatory diagram of the winding looseness detection operation, and is an explanatory diagram of tightening torque.

In the figure, the same reference numerals as in FIG. 9 is a pulse period measurement timer circuit; 20.
21 is a motor drive power amplifier circuit, 22 is a reel motor,
23 is a tachometer, and 24 is a tension detection circuit. Note that each process number in FIG. 4 is shown in parentheses.

The magnetic tape control device used in this embodiment is as shown in FIGS. 2 and 3, and the same single reel cartridge tape as the conventional example shown in FIG. 7 is used.

The reel motors 5 and 22 are connected to the reel of the cartridge I and drive the reel to feed or wind up the tape to run and stop the tape, and the reel motor drive control circuit 9 controls the amount of tape wound on the reel and the device control. Based on the running command from the section, the reel motor 5.22 is driven and controlled so that the magnetic tape runs or stops at a predetermined tension and speed.

The tachometer 6.23 measures the rotational speed and angle of the reel in order to servo control the reel motor 5.22. In this example, a digital 1-totachometer is used, and the tachometer measures the rotational speed and angle of the reel every time a predetermined rotational angle is moved. A pulse signal is obtained. The tachometer usually includes a 2 & Il signal circuit, and the phase difference thereof changes depending on the direction of rotation of the reel.

The receiving circuit/direction determining circuit 18 receives the signal from the tachometer 6, measures the phase difference between the two sets of palme signals from the tachometer 6, determines the rotational direction of the reel motor, and rotates the reel motor according to the determined direction. Output direction signal.

The rotation pulse integration circuit 7 includes a tachometer pulse counter 1
0, and the rotation angle of the reel is measured by adding or subtracting the tachometer pulse signal depending on the direction signal.

The slack amount determination circuit 8 includes a count value register 1 that temporarily stores the count value of the tachometer pulse counter 10.
7, Comparator 11, Looseness determination table 12, Selector 13, Excessive reference value register 14, Normal reference value register 1
5, compares the counted tachometer pulse integrated value with a determination reference value, determines the amount of loosening, and outputs a signal 2 instructing the processing.

Next, a method for detecting winding loosening of a magnetic tape in a magnetic tape device will be described based on the flowchart of FIG. 4 and with reference to each figure.

After the loading operation starts (200), the cartridge 1 is mounted (201) and connected to the reel motor 5 (202).

Thereafter, the reel is wound in the unwinding direction (in the direction of arrow B in FIG. 7) to remove slack (203), and this continues until the reel stops rotating (204).

In this case, as shown in FIG. 7, a leader block 3 is provided at the tape starting end of the single-reel cartridge tape for connection with the pull-out mechanism when loading the tape.
is provided, and is fixed to the tape outlet of the cartridge while the tape is being stored. Therefore, when the reel is rotated in the rewinding direction, the tape is wound tightly, and by this tightening, the tape sagging outside the reel inside the cartridge 1 is wound up.

Next, the tachometer pulse counter 10 is cleared and initial settings are performed (205), and the reel motor 5 is moved in the tape rewinding direction (in the direction of arrow B in FIG. 7) with a relatively strong torque that does not damage the magnetic tape. The tape is driven to gradually apply strong tension to the tape and wind it up (206).

At this time, if there is no slack in the tape, the reel will hardly rotate, but if there is slack in the tape, it will be tightened and the reel will rotate according to the amount of slack.

By the way, the reel motor 5.22 is equipped with a tachometer 6.2 that measures the rotational speed in order to control the original tape running speed.
3 is provided. . For example, a 500-slit code plate and two sets of optical sensors are provided to output output signals. This is received by the receiving circuit/direction determining circuit 18 to determine the direction, and further by the rotation pulse integrating circuit 7,
By counting the pulse signals output according to the rotation angle and its direction, the amount of rotation of the reel can be measured.

Therefore, by observing the amount of rotation during the tightening process, the amount of loosening of the tape can be detected.

The tightening torque described above is applied as shown in FIG. In other words, the torque applied during slack removal is extremely weak, and the subsequent winding looseness detection operation starts with a small torque, and while the reel is rotating, the torque at that point is maintained until the reel is tightened. Once stopped, gradually increase the torque to the maximum allowable value without damaging the magnetic tape.

In order to do the above, under the control of the motor drive control circuit 9, the tape tightening torque is gradually increased to determine whether the winding torque is at the maximum value (207), and if it is not at the maximum value, the reel is Deciding whether to rotate or not 20
B) If the reel does not rotate, further increase the torque,
It stops when it reaches the maximum value.

If the reel rotates before the maximum torque is reached, the tachometer pulse counter 10 counts and integrates the tachometer pulse signal (209) and continues to stop until the maximum torque is reached.

Thereafter, the accumulated value of the tachometer pulse counter 10 is stored in the counter value register 17, and the comparator 1 is further stored in the counter value register 17.
Enter 1.

On the other hand, the excessive reference value and the normal reference value are sent from the motor drive control circuit 9 to the looseness determination circuit 8, and stored in the excessive reference value register and the normal reference value register 15, respectively.

At a predetermined time in the winding slack detection operation, a select signal is sent from the motor drive control circuit 9 to the selector 13 and the slack amount determination table 12 to perform a switching operation.

In this way, first, the comparator 11 compares the value that has been stored in the counter value register 17 with the excessive reference value stored in the excessive reference value register. As a result, as shown in Figure 5, when the excessive reference value is exceeded, it is determined that the looseness is large and extremely loose (211).
, and outputs a signal instructing to stop loading and eject the cartridge by referring to the looseness determination table in the comparison output (212).

In addition, if the excessive reference value is not exceeded, switch the selector 13 and compare it with the normal reference value (213). >, referring to the loosening amount determination table 12 based on the comparison result, and outputting a signal instructing to execute rewinding after loading (214).

If the above comparison result does not exceed the normal reference value, it is determined that there is no loosening, and a signal to continue the loading operation is output (2
15).

Although the embodiments have been described above, the present invention can also be implemented as follows.

(11) The above control can be realized by a circuit or the like, but it can also be realized by software using a microprocessor.

(2) It is also possible to arbitrarily set the torque value and judgment reference value for tightening for loosening detection depending on the manufacturing environment, usage conditions of the medium (magnetic tape), etc.

(3) It is also possible to provide a learning function that stores the conditions and looseness measurement values in the case of (2) above in association with the surrounding environment and reflects them in the next operation.

〔Effect of the invention〕

As explained above, the present invention has the following effects.

(11) Looseness of the magnetic tape in the cartridge can be reliably detected and dealt with.

(2) Even if a cartridge is used that has looseness due to low temperatures, vibrations during transportation, etc., the running of the magnetic tape is not affected by this, and the reliability of data recording and playback can be prevented from being compromised.

FIG. 7 is a schematic diagram of a conventional single-reel cartridge tape.

l--cartridge 5- Reel motor 0・-tachometer pulse counter Comparator 2-...Looseness amount judgment table 3-Selector

[Brief explanation of drawings]

FIG. 1 is a diagram showing the principle of the present invention, FIGS. 2 to 6 are diagrams showing one embodiment of the present invention, FIG. 2 is a block diagram of a magnetic tape control device, and FIG. 3 is a diagram showing the above magnetic tape control device. FIG. 4 is a detailed diagram of a part of the control device, FIG. 4 is a processing flowchart of the embodiment, FIG. 5 is an explanatory diagram of winding looseness detection operation, and FIG. 6 is an explanatory diagram of tightening torque.

Claims (1)

[Claims] As a pre-processing of the tape transport operation when recording/reproducing information using a single-reel cartridge tape, the amount of slack in the winding of the tape loaded in the magnetic tape device is detected; In a magnetic tape winding looseness detection method in a magnetic tape device that makes it possible to perform winding looseness elimination operation or abnormality recovery processing according to the value, the above-mentioned cartridge tape installed is driven to rotate in the tape rewinding direction with a weak torque. to remove slack in the tape, then tighten the tape by gradually increasing the torque in the tape rewinding direction to the maximum torque that does not damage the tape, and reduce the amount of rotation of the tape reel during said tightening. 1. A method for detecting winding slack of a magnetic tape in a magnetic tape device, the method comprising detecting the amount of tape winding slack by observing.