JPS5819759A - High-speed taking-up system of reel - Google Patents

Abstract

PURPOSE:To ensure a high-speed take-up operation of a reel in a stable way although the vacuum column is short, by detecting the tape reel got stout with an increase of the tape take-up speed by a step, with each prescribed period corresponding to a constant period and then controlling the tape take-up speed. CONSTITUTION:The tape loop position detectors 3A and 3B are set into a vacuum column including a file column 2A and a machine column 2B. The tape loop got stout with an increase of the tape take-up speed by a step is deteced with each prescribed period corresponding to a certain period. The tape take-up speed is increased by a step or kept constant when the tape loop positions alpha and beta are within a prescribed level. While the take-up speed is lowered when the positions alpha and beta exceed the prescribed level. In such way, a high-speed tape take-up operation is possible in a stable way although the vacuum column is comparatively small with a comparatively small induced voltage constant of a reel motor.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention also relates to a high-speed reel winding system, and more particularly to a high-speed reel end-of-life system for a magnetic tape device having a vacuum column and a tape loop position detector.

Conventional magnetic tape apparatuses of this type (C have a very short vacuum column and Z can sufficiently follow the reel and mop feeding speeds) have been able to do so.

However, as magnetic tape devices become smaller and the length of the vacuum flap b tends to become shorter, it is currently difficult to achieve stable high-speed reel winding even when the induced load of the reel motor is relatively small. The problem has arisen that conventional speed control methods are no longer able to provide satisfactory results.

The present invention has been made in view of the above circumstances, and its purpose is to solve the problems of the conventional reel high-speed winding system, as described above, and to provide a vacuum column with a relatively short length. An object of the present invention is to provide a speed control method that enables stable high-speed winding of a reel even when the induced voltage constant of a reel motor is relatively small.

The above-mentioned object of the present invention is to perform high-speed reel winding in a magnetic tape device equipped with a vacuum column and a tape loop position detector, in which the tape winding speed is controlled to increase stepwise at regular intervals at the start of high-speed reel winding. In the method, a tape loop that has become larger due to a one-step increase in the zero-marked tape winding speed is detected every predetermined cycle corresponding to the fixed cycle, and the tape loop position is within a predetermined level in the vacuum column. , the tape winding speed is increased by one step or remains constant over the entire history, and if the tape loop position exceeds a predetermined level in the vacuum column, the tape winding speed is increased by one step. This is achieved by a high-speed reel winding system that is controlled in a stepwise descending manner.

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 is a schematic side view showing the main parts of the magnetic tape device i't. In the figure, IA is a file reel, IB is a machine reel, 2 is a file column, 2B is a machine column,
3A and 3B are tape loop position detectors, and square is a capstan. In addition, the height of the tape loop from the standard fishing position for the two people in the α and Ke file columns is shown, and the height (downward from the reference position of the tape loop in the β machine column 2B) is shown, respectively.

Figure 2 shows all changes in capstan tape feed speed, Figure 3
The figures show the corresponding variations in file reel/tape loop height and α).

Normally, as shown by the solid line in Fig. 2, at the start of high-speed tape winding, the tape feeding speed of the capstan increases at a constant period △ to a constant speed width △Vm/sec - (j-) every second. The maximum unwinding degree ■max is written in the n・△7 second line.Then, the speed is continued at a constant speed ■max, and the speed is gradually increased to K'tf just before the tape winding is completed.At this time, the tape loop of the file reel is 3 [IC fluctuates as shown by the solid line. In FIGS. 14 and 3, lf is the level of the tape loop when the file reel motor is set to the total maximum rotation speed.

The present invention will be described in detail below, taking as an example a case where the capstan's tape feed speed v1 and the file reel motor's maximum winding speed match at time 3+1 t□.

Since the tape loop is stable at time C, 1.
Increase the capstan tape feed speed by 7 seconds/:). △ is used to detect the tape loop position every second.

At this time, if it is determined that △vTh in 8IJ △v-2 (1-1)/△t -...- (1), then time t! The tape loop will not come off upwards from the two people in the file column during the time △ seconds 1 + 1. Note that in equation (1), l indicates the length of 1/2 of the length of two file columns.

Since the response of the reel end-of-time speed is delayed with respect to the increase in capstan speed, the tape loop becomes temporarily large between times t1 and t1+, as shown by the broken line in the third row. This fluctuation is detected at the level l.

When it is detected that the tape loop exceeds the level l, 1=, vc lowers the tape feeding speed of the capstan by one step.

Since the file reel is in the direction of increasing the number of tapes, after time t, the tape loop change does not increase further by 1+1, and the tape loop becomes stable.

On the other hand, the tape loop position detection level l of the machine column 2B is a level l that gives the maximum rotation W to the machine reel motor. is obtained by subtracting the change lΔ7 in the steady deviation of the tape loop at the minimum diameter of the machine reel, which corresponds to ΔV given by the above equation α). That is, 1-1-7. v...C)! rl
It is expressed as O.

Fig. 4 shows the variation in the machine reel/tape loop height (β), and the solid line shows the change in capstan tape feeding speed in the normal case (Fig. 2 1fl actual p?).
It is shown in ) shows the variation in the machine reel/tape loop feed rate. In addition, when setting as shown in the above equation e) to the point, at time tj, the tape feed of the capstan once is △v (1 stage 1/)
The tape loop is i'j'I N! at time tj+□. l
It will not be larger (lower K) and will be stable2). Since the machine reel is in the direction of decreasing tape amount, at time t
at the level 1mj+].

Be sure to take out this f'1. , Since the capstan tape feed k (1 degree can be lowered by one step) from K, the tape loop is stabilized.

As described above, according to the present invention, in a magnetic tape device equipped with a vacuum column and a tape loop position detector, the tape winding speed is controlled to increase stepwise at regular intervals at the start of high-speed reel winding. In the reel high tracing winding system, the tape end speed is 1182.
The tape loop, which has become larger due to the floor speed - 1, is plugged at predetermined intervals corresponding to the fixed cycle, and if the tape loop position is within the predetermined level in the vacuum column, the tape is wound. The tape winding speed is further increased by IP'7 or is kept constant, and ■] If the 0th dip loop position exceeds the predetermined level in the empty column, the tape winding speed is controlled to decrease by one step. Therefore, when the length of the vacuum column is relatively short and the electromotive force voltage of the reel motor is relatively small, it is possible to perform stable high-speed winding of the reel. In particular, even when the amount of tape on the reel is small and the reel tape winding speed cannot catch up with the tape feeding speed of the capstan, it is possible to achieve high-speed reel winding while maintaining a stable tape loop.7 play.

[Brief explanation of drawings]

Figure 1 is a schematic side view showing the main parts of a magnetic tape device;
The figure shows changes in capstan tape feed speed, Figure 5 shows changes in tape loop height on a 77' reel, and Figure 4 shows changes in machine reel tape loop height. It is a figure showing tlJl. IA near aisle reel, 1η: machine reel, 2A: file column, 2B = machine column, 3A, 3B: tape loop position detector, 4: capstan. Figure 1

Claims (2)

[Claims] (1) A high-speed reel winding system in a magnetic tape device equipped with a vacuum column and a tape loop position detector, which controls the tape winding speed to increase step by step at regular intervals at the start of reel winding. , said tape winding! The tape loop, which has become larger due to the increase in speed by one step, is subjected to a predetermined exposure 1 corresponding to the constant circumference gj.
When the tape loop position is within a predetermined level in the vacuum column, the tape winding speed is increased by one step or kept at a constant level, and the tape loop is The position is within the vacuum column.
A high-speed reel take-up system characterized by controlling the tape winding speed to be lowered by one step if it exceeds /-. (2) The speed outer width of one step of the tape winding speed performed at each fixed period is 2(lt, )/△t (here, △t
is the constant period, ) is the length of the file column, and 7! This figure shows all the tape loop positions when the fld file reel motor is at maximum @conversion. )
1. The method for winding up buds according to claim 1, wherein the method is determined so as not to become larger.