JPH0428655A - Run stabilizer for running medium - Google Patents

Abstract

PURPOSE:To uniformly stabilize the run of a tape as a whole by providing a tension regulator which has a structure of a rotation impedance roller (with the moment of inertia J relatively greater) right after the output of a supply reel to control the vertical vibration of the tape and the tensile variation of the tape at the same time. CONSTITUTION:An arm 25 which moves in the direction of rotation on a shaft 25a is mounted with a tension roller 24. The tension roller 24 is placed right after the output of a supply reel 2 so that the vertical vibration of a tape 3 fed out of the supply reel 2 and the tensile variation of the tape can be controlled at the same time by the tension roller 24. It is thus possible to put the tape 3 into stable run.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention provides a magnetic tape device or a film device in which, when the recording medium runs, the tension of the recording medium is kept constant and the tension in the traveling direction of the running medium is kept constant. This relates to a running stabilization device that eliminates vibrations (called longitudinal vibrations).

Generally, in devices that use tapes, films, etc. as media, tension and longitudinal vibration must be managed, and various difficult measures are taken.

[Conventional technology]

Fig. 4 is a perspective view showing the tape running system of a conventional helical scan VTR, Figs. 5 and 6 are plan views thereof, and Fig. 7 shows an example of a magnetic tape pattern recorded on a conventional VTR. FIG.

First, a conventional helical scan type VTR will be briefly explained with reference to FIG. Supply of cassette (1)! Magnetic tape (3) F wound around J-7L' (2)
i, it is pulled out from the cassette (1) by the entrance side guide rollers (4), (5) and the exit side guide loaf (6). After the magnetic tape (3) comes into contact with the full-width erasing head (7) and the binder dancer row (8), it is wound around the rotating drum (9). Here, the impedance roller (8) is connected to the supply in the cassette -/L' (
2) prevents uneven rotation (vibrations in the tape's traveling direction, causing shifter, wow, and flutter phenomena) from being transmitted to the rotating drum (9). A roller that rotates without slipping. Furthermore, after the magnetic tape (3) comes into contact with the audio erasing head (10) and the audio writing control head (11),
and pinch rollers (13).

In this way, the magnetic tape (3) is attached to the capstan (12)
and pinch rollers (13) and are pressed,
By rotating the capstan (12), it becomes possible to run for recording and playback, and the cassette (12) is rotated.
) is wound onto the take-up reel (14). Here, the tension ball (15) is a pin that moves as shown by the arrow, and is connected from the supply Lee/M (2) to the pinch roller (13).
This is to control the tape tension of the magnetic tape up to the point where the tape is sandwiched between the capstan and the capstan (12). That is, if a large tension is applied to the magnetic tape for some reason, the tensilon pole (15) moves in the escape direction (b direction) to lower the tension, and when the tension decreases, it moves in the direction of pushing the magnetic tape (a7i-same). Is the magnetic tape constantly running under tension? Control constant.

The rotating drum (9) is composed of a pair of an upper rotating drum (16) and a lower fixed drum (17).
A video head (18) built into the upper rotating drum (16) sends video signals to the video tracks (19) of channels 1 and 2 of the magnetic tape (3), as shown in FIG.

(20) is recorded. Also, the audio signal is recorded on the audio tracks (21) and (22) of channels 1 and 2 of the magnetic tape (3) by the audio recording section of the audio/control head (11), and the control signal is recorded on the audio tracks (21) and (22) of channels 1 and 2 of the magnetic tape (3). The control signal recording section 11) records the signal on the control track (23) of the magnetic tape (3). The full-width erase head (7) erases all the video signals, audio signals, and control signals that have been recorded on the magnetic tape (3), and the audio erase head (10) is for so-called post-recording. belongs to.

In this way, by bringing the magnetic data 7(3)i pulled out from the cassette (1) into precise contact with each head,
As shown in FIG. 7, each signal on the magnetic tape (3) can be accurately recorded and reproduced.

As mentioned above, the VES system/I/M type rogueing system adopted in inch consumer VTRs allows the positional relationship between the cassette and the rotating drum to be close to each other.
The TR itself can be made smaller, and at the same time, the so-called loading time for pulling out the magnetic tape from the cassette and loading it onto the rotating drum can be shortened. Therefore V'HE
It is widely used in formula V.

[Problem to be solved by the invention]

Since the conventional M-type loading device is configured as described above, it has the advantage of making the entire VTR smaller and shortening the loading time. However, because the magnetic tape bus (between the cassette and the drum) is short, the cassette ) The reel rotation unevenness in the hole is easily transmitted to the rotating drum (9), causing jitter and wow in the reproduced image. Despite this, the problem was not solved completely.

In particular, uneven rotation of the supply reel (2) is likely to occur, and the frequency of this rotational unevenness changes depending on the JIK of the magnetic tape placed on the supply reel (15), (su, (7), (8), (5
) approaches the resonant frequency of the traveling path of the rotating drum (9
), where the video head (18) jumps into the tape, there is a lot of vibration, which usually causes large jitters and wows.

This invention was made in order to solve the above-mentioned problems, and it is possible to use the M-type loading method as is, making it compact and taking advantage of the short loading time). The object of the present invention is to obtain a running stabilizing device for a running medium that can reduce longitudinal vibration.

[Means to solve the problem]

The tape running stabilizing device according to the present invention has a supply reel output.
A roller that rotates immediately after the tape and has a large sexual moment is provided, and although it rotates smoothly without causing the outer surface to come into contact with the tape, this roller itself moves almost at right angles to the tape, causing the tape to The tension is also controlled.

[Effect]

The tape running stabilizing device according to the present invention controls the tape tension by moving the rotating shaft itself, and also suppresses the longitudinal vibration of the tape by the roller structure, thereby stably running the tape.

Moreover, by installing it immediately after the outlet side of the supply reel, the tape can be run without worrying about the resonance system of the tape running system.

cam example] Hereinafter, a dormitory embodiment of the present invention will be explained with reference to FIG.

In FIG. 1, the same or corresponding parts as in the conventional device are given the same reference numerals, and the explanation thereof will be omitted. (24) is a tension V-sealing roller for braking the tension of the tape and removing longitudinal vibration; (25) is a tension-sweeping roller (24) (f') M(2
4a) Tensei low farm that is fixed and moves in the rotational direction around the rotation axis (24a), (26) is the supply '
)-/l' (2) is a tension band that forcibly applies the brake, and (27) is a mounting portion that fixes the other end of the tension band (26) to the main deck. Here, the tension expansion pad (26) is generally made of a flexible material such as a phosphor bronze plate, and surrounds the outer diameter of the pillar section (2a) of the supply reel disk (2), and the tension expansion pad (26) The inner side is shaped like a feather A/) (26a) to increase friction. (28)
is a mounting part for fixing the end of the tension pump (26), and this is attached to the other end of the tension tension roller arm (25) which rotates around the shaft (25a). One end of the tensile strength farm (25) is attached to the spring (2
9), a part (30) of the main deck part is pulled. The tension roller arm (25) is attached to the shaft (25
It is fixed to the deck by a) and rotates about the shaft (25a) in the direction of the arrow shown by the dashed line.

Here, the structure of the tension roller (24) will be explained with reference to the sectional view of FIG. 2A. (24a) is the central axis of the tension tension roller (24), which is an Alten ball and is fastened to the arm (25) by caulking or the like. A roller (24) is inserted into this port/I/ (24a),
Rotates smoothly. As shown in the cross-sectional view, this roller (24) is desirably a disc-shaped member having a large outer diameter at the upper and lower parts, and is made of a material having a large mass such as brass, so that the moment of inertia is large. (24b) is a Nufnut bearing that smoothes rotation.

This roller (24) is in surface contact with the magnetic tape (3) in the width direction, and rotates uniformly and smoothly with the progress of the tape, with the roller (24) LD bow # (24a) as the central axis.

Here, let us find the moment of inertia of the roller (24). Since the roller (24) has a complicated shape as shown in FIG. 2A, it is now considered as a cylindrical loaf with a diameter t as shown in FIGS. 2B and C. Considering a cylinder as shown in Fig. 2B and C, we will calculate the moment of inertia with the two axes of rotation. Using the symbols as below, R: Radius of the cylinder r: Distance from the axis of rotation to any minute part t: Length of the cylinder φ: Position angle of the minute part ρ: Retention degree (although different from Fig. 2 A) dm: Mass of the minute part m: Total mass of the cylinder dI: Moment of inertia of the minute part about the z-axis lz:
Assuming that the minute portions of the moments of inertia r and φ of the cylinder with respect to the z-axis are dr and dI, and taking a minute portion of the volume t@dr11rdφ that is a distance rK from zIM, the mass d1n is: dmx=ρ・t11r11drIIdφThe moment of inertia of this minute portion is, dI=r” dm=ρ・t*r”edr@dφ Therefore, for the entire cylinder, here, the total mass of the cylinder is given by the following formula, so mw
The moment of inertia of the cylinder with respect to ρπR”t zllllIi is iz =
-m R' As described above, if we consider a minute part of an object, find the small moment of inertia of that part about the axis of rotation, and then collect it over the whole, that is, if we integrate it in the case of a continuum, we can find the moment of inertia of the whole. It turns out.

In this way, the moment of inertia (moment of inertia) is calculated by the square of R.As in the 29th friend, the diameters of the upper and lower discs are chosen to be large and the rotational loss of the shaft part is reduced, thereby reducing the longitudinal vibration due to the tape's traveling direction. can be excluded. That is, it functions as a stabilizer that removes jitter components.

The operation of the roller fitting stencil seal loaf (24) having the moment of inertia as described above will be explained with reference to FIG. In order to perform recording and playback operations according to the tape format A-mat determined by the running system in Figure 1, the tape (
3) The tape speed and tension must be constant at each point on the travel path. In recent high-density recording systems, speed, tensile uniformity, and longitudinal vibration reduction are particularly required. In the running system shown in Figure 1, the tension W of the tape is determined by the hub diameter of the tape (3) remaining on the supply reel (2).
Tensilan eim is necessary because the numbers are usually very different. If the tape (3) becomes slack due to some kind of ground, the tension roller (24) moves in the direction of the arrow a indicated by the - dot @ line. Then, since the attachment part (28) attached to the other end of the arm (25) moves to the left, the tension belt (26) is also pulled to the left. Since the other end attachment point (27) is fixed to the deck, the felt part (26+a) of the tensile band (26) comes into close contact with the outer diameter surface of the center column part (2a) of the supply reel disk, and the supply A brake is applied to the rotational speed of the Luteinuku, and a predetermined tensile force is applied to the running tape. On the other hand, if the tape (3) becomes taut due to some reason, the tension roller (2
4) moves in the direction of the arrow, and Tensilan band (26)
moves to the right, the brake is released, and supply, -/L
/(2) rotates lightly.

Here, −i is tension P, torque T, and supply reel radius T.
The relationship P = T/r holds true between them.

Therefore, when using a tape cassette wound around a supply reel hub with a large diameter, or when a large amount of magnetic tape is wound around the supply reel hub (as shown in Fig. 1, 3a), the above relational expression Since the radius r is large and the torque T is constant, the force P is small. Therefore, the elastic force of the spring (29) is overcome by the tape tension y, and the tension band (24) moves in the direction of arrow a, and the tension band (26)
a) makes contact and the brake is activated. Then, the torque T increases and the tension P increases again according to the above-mentioned relational expression.

On the other hand, if a small amount of tape is wound around a supply reel hub with a small diameter (Fig. 1, 3 c f), first the tension is large, and the tension roller (24) is placed in the direction of the arrow. , the tensile band (26) separates from the column part (2a) of the supply reel disk, and the braking force is lost.Then, the torque T decreases and the tension decreases.

That is, according to the tension blowing mechanism shown in FIG. It is important to keep the tape tension constant, and during this time the tape (3) has a tension of 1 as shown in Figure 2AK.
The stabilizer effect is maintained because it rotates in close contact with the outer surface of the arrow (24). It is controlled in any tensile run while maintaining the anti-jitter stabilizer effect.

Figures A and B show data on the east side of jitter during normal playback operation. , FIG. 3 A4 shows the jitter component characteristics in a conventional manner, and FIG. 3 BVi shows the jitter component characteristics in an apparatus according to the present invention. Because two stabilizers are placed after the supply reel outlet and the tape tension is controlled at the same time, changes such as uneven rotation within the supply reel are transmitted to the entire tape running system.
Jitter is reduced by approximately 10dB.

In the above embodiment, the Tensilon roller (24) of the present invention is provided in place of the conventional impedance roller (8), and fc may be left as is.

In the above embodiment, the shape of the tensilon roller (24) is
Although shown in Figure A, the shape is not limited to this. If Nubase is allowed, it is desirable to choose one with a larger diameter and one that is closer to ILiL.

The angle at which the tape is wound around the outer surface of the Tensilon roller (24) may be such that the tape and the outer surface do not slip, and this angle is not limited.

In addition, this invention applies to the β method V as a representative method other than the M type loading method adopted in the VHS system.
The U-shaped loading method used in TR can be similarly implemented (see FIG. 8). -Although the description has been made with reference to a VTR, which is a typical example of a magnetic tape device, the present invention can also be widely used in other devices that use media such as paper tape or film.

〔Effect of the invention〕

As described above, according to the present invention, the rotating impedance roller (moment of inertia) is used in the loading mechanism.
J's relatively large) Seizo is supplied with a long-lasting evening legier letter! Since it is installed immediately after the output of the J-rule and simultaneously controls the longitudinal vibration of the tape and fluctuations in tape tension, the running of the entire tape can be made uniform and stable, and as a result, jitter can be greatly reduced. Further, since the conventional impedance roller is not required, it is possible to contribute to miniaturization and cost reduction.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of the present invention, FIG. 2A is a detailed sectional view of the Tensilon roller of the present invention, FIGS. 2B and C are diagrams explaining the moment of inertia, and FIGS. 3A and B are Figure 4 is a perspective view showing the conventional M-type loading mechanism; Figure 5 is a plan view showing the mechanism during conventional loading; FIG. 6 is a plan view showing a conventional unloading mechanism, FIG. 7 is a view showing a tape pattern, and FIG. 8 is a perspective view showing a U-shaped loading mechanism employed in a β-type VTR. In the figure, (1) is a cassette, (2), (14)
is Lee/l/, (3) is a magnetic tape, (24) is a tensilon roller, (25) is an arm, (26) i'1. Tensile band, (27), (28) U tensilon band attachment part, (29) is spring, (9) is rotating drum,
(13) Fi pinch roller, (12) is the capstan shaft. Note that the same reference numerals in each figure indicate the same or corresponding parts. Agent Patent Attorney Masuo Oiwa Diagram B Diagram C Diagram A Diagram 8 VTR Rider Hiroyu Visitor Diagram of the Second Date and Moon

Claims (1)

[Claims] (1) Mechanism for traveling on a flexible traveling medium;
Stable running of a running medium, characterized in that a control pin for controlling the tension of the running medium is structured as a rotating roller to provide a moment of inertia, thereby simultaneously controlling the tension of the running medium and vibrations in the running direction. Device.