JPH09275047A - Device for giving tension for winding capacitor film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cover a wide tension control range and improve responsibility even for a low tension by attaching a plurality of swing arms mutually symmetrically relative to a connecting shaft with a system for giving a rotating force to the swing arms. SOLUTION: A dancer roller 1 is connected in a rotatable manner at the tip of a swing arm 2, the swing arm 2 is connected to a system 3 for giving a rotating force with a shaft C and is extended in both directions symmetrically relative to the shaft C. A force transmitted by the system 3 tries to rotate the swing arm 2, so that the dancer roller 1 receives the force in the same direction accordingly, thereby tensioning a film f. Also, for the system 3, a DC motor is used and the number of swing arm 2 can be increased as required but normally two is desired. By doing this, a wide tension control range can be covered and also the responsibility can be improved even though a low tension is required.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tension applying device which is attached to a film winding device for manufacturing a film capacitor and applies appropriate tension to the film.

[0002]

2. Description of the Related Art A film capacitor which is a wound type capacitor is manufactured by winding a metal-deposited plastic film such as polyethylene terephthalate (PET) or polypropylene (PP). The film winding method at this time is performed by winding the film around a winding shaft and rotating the film, but the film must be wound while applying an appropriate tension to the film. If the tension at this time is not appropriate, problems will occur in the electrical characteristics of the capacitor as a product.

For example, if the tension is too high, the film stretches and locally wrinkles, or the film becomes tightly wound and becomes difficult to flatten when flattened by a hot press after winding. Such a phenomenon occurs that the electric characteristics vary. On the other hand, if the tension is too small, the film will meander, and as a result, the widths of the overlapping portions of the two wound films will shift and the electric capacitance will not be constant.

As described above, when winding, the winding proceeds while giving an appropriate tension. Since the appropriate value of this tension varies depending on the material, thickness, width, etc. of the film, the type of film is different. Each time it is replaced, the winding must be performed so that the winding device is re-applied with proper tension. A conventional method of applying tension will be described below with reference to FIG.

As shown in FIG. 3, a dancer roller 11 for applying tension is installed in a film traveling path between a film feeding roller (not shown) and a film winding shaft (not shown). . This dancer roller 11
Is attached to a swing arm 12 capable of swinging, the rotating shaft 13 is connected to the other end of the swing arm 12, and the other end of the rotating shaft 13 is connected to another arm 14. A spring 15 having one end fixed is connected to the arm 14, and a force is always applied to one end of the arm 14 by this spring. For example, when a force F indicated by an arrow acts on the arm 14, this force is transmitted to the swing arm 12 via the rotary shaft 13, and a moment gives a rotational force to the swing arm 12. The rotating force of the swing arm 12 is the dancer roller 11 connected to the swing arm 12.
Is applied to the film f wound around the dancer roller 11 at an angle of about 180 degrees, and a force balanced with this moment is applied as tension.

[0006]

By the way, in recent film capacitors, miniaturization and higher capacity have been carried out, and the material, thickness, width, etc. of the film, which is a material, has become various depending on the use. It was For example, as the material of the film, polypropylene (PP), polyethylene terephthalate (PET), or the like, the film thickness is 1.5 to 12 μ, and the film width is 5 to 30 mm. Therefore, the winding machine is also required to be capable of coping with the diversification of materials.

As described above, since the proper value of the tension varies depending on the material, thickness, width, etc. of the film, it is preferable that the proper tension can be easily set according to these changes. The magnitude of tension currently required is about 10 to 2
Since it covers a wide range of 00 g, it is necessary to prepare some kinds of springs and replace them appropriately in order to cover this tension range and set the tension appropriately. Further, in the case of low tension, there is also a problem that the swing arm tracking becomes incomplete and thus the responsiveness deteriorates. In order to solve this, measures such as attaching a counter balance to the arm 14 and reducing the moment of inertia of the swing arm are taken.

The present invention has been made in consideration of the above problems, and provides a tension applying device capable of covering a wide range of tension control in a film capacitor winding device and having good responsiveness even at low tension. The purpose is to

[0009]

SUMMARY OF THE INVENTION The above object is to change a rotatable swing arm connected to a dancer roller from a conventional one arm to a plurality of arms, and to connect these arms to a system for imparting a rotational force to the arms. It was achieved by placing them symmetrically with respect to the axis.

That is, the present invention comprises a dancer roller, a rotatable swing arm connected to the dancer roller,
A tension applying device for winding a condenser film, comprising: a system for applying a rotational force to the swing arm, wherein a plurality of the swing arms are attached symmetrically to each other with respect to a connecting axis with the system. To do.

According to the present invention, since a plurality of swing arms are attached symmetrically to each other as described above, one swing arm serves as a counter balance for the other swing arm. Also, the other arm not only acts as a counter balance, but by installing a dancer roller on this as well,
The device can apply tension at multiple points. The dancer roller may be attached to only one swing arm or may be attached to a plurality of swing arms. In general, when setting a low tension, it is advantageous to install a dancer roller on a plurality of swing arms using couples, and when setting a high tension, a one-arm system in which a dancer roller is installed on only one arm is advantageous.

The system for applying a rotational force to the swing arm may be any method such as the conventional method using a spring, but it is advantageous to use a DC motor to automatically control the tension. Is.
In this case, a constant tension can always be applied to the displacement of the dancer roller.

The number of swing arms can be increased if necessary, but usually two swing arms are preferable. The number of swing arms can be appropriately determined depending on the magnitude of the required tension, the need for couples, the problem of space in the device, and the like.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a front view of a tension applying device of the present invention, and FIG. 2 is a side view thereof. In the figure,
1 is a dancer roller, 2 is a swing arm, and the dancer roller 1 is rotatably connected to the tip of the swing arm 2. The swing arm 2 is connected to a system 3 for applying a rotational force by a shaft C and extends symmetrically with respect to the shaft C in both directions.

Since the force transmitted from the system 3 for applying the rotational force tends to rotate the swing arm 2 in the direction of the arrow, the dancer roller 1 receives the force in the same direction accordingly and pulls the film f. become. The broken line shows the state where no tension is applied.

In the above, a DC motor is used as the system 3 for applying the rotational force. The DC motor has two shafts, a swing arm is attached to one end, and a potentiometer is connected to the other end. The potentiometer converts the swing arm displacement angle into an electric signal and outputs it, and the tension fluctuation can be adjusted automatically. The system 3 for applying the rotational force is not limited to the DC motor, and a spring or any other device can be used.

When a tension applying device having two swing arms is used, the tension acting on the film is half the film tension of the conventional one arm when the same acting force F is applied, so that it is wide. The tension control range can be covered. Also, if the film tension is the same, the length from the rotation axis of the swing arm can be halved compared to the conventional one arm, so the moment of inertia of the swing arm becomes smaller and the problem of responsiveness is improved. To be done.
The following equation shows this relationship.

Now, the torque generated by the motor is Tm (kg
cm), the length of the arm from the rotation axis is L (cm), the force acting on the dancer roller is F, and the tension applied to the film is T, when the swing arm is one arm, Tm =
Since it is LF, F = Tm / L. Therefore, the tension T applied to the film is T = F / 2, so T =
F / 2 = Tm / 2L.

On the other hand, in the case of two swing arms, that is, in the case of both arms, since Tm = 2LF, F = Tm /
2L, and the tension T applied to the film is T = F / 2
= (Tm / 2L) · 1/2.

In the above, the swing arm may be provided with dancer rollers on both sides, or may be provided on only one side. When the dancer rollers are provided on both sides, as shown in FIG. 1, tension can be applied at two points during the film running, so that the capacitor characteristics can be further improved.

[0021]

As described above, when the tension applying device of the present invention is used, a wide range of tension control can be covered, and the response is improved even when low tension is required. It is possible to cope with the diversification of wound films and diversification of capacitor applications.

[Brief description of drawings]

FIG. 1 is a front view of a tension applying device that is an embodiment of the present invention.

FIG. 2 is a side view of the tension applying device of FIG.

FIG. 3 is an explanatory view illustrating a method for applying tension to a running capacitor film by a conventional tension applying device.

[Explanation of symbols]

1 ... Dancer roller, 2 ... Swing arm, 3 ... System for applying rotational force, C ... Swing arm axis, f ... Film.

Claims (3)

[Claims] 1. A tension applying device for winding a condenser film, comprising: a dancer roller, a swing arm connected to the dancer roller, and a system for applying a rotational force to the swing arm, wherein the swing arm is connected to the system. The tension applying device is characterized in that a plurality of tension applying devices are attached symmetrically with respect to an axis. 2. The tension applying device according to claim 1, wherein two swing arms are attached. 3. The tension applying device according to claim 1, wherein the system for applying a rotational force to the swing arm is a DC motor.