JPH10154631A - Film capacitors and metallized films for capacitors - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a film capacitor and a metallized film for a capacitor, which can achieve both stability and security of capacitor capacity. SOLUTION: The insulating film 3 and the film 3
An edge division margin for dividing one side edge portion of the metal deposition film as a connection portion 12 from another portion of the metal deposition film. 8
And an electrode division margin 16 that divides the metal deposition film into a large number of electrode portions 14 in the other portion of the metal deposition film, thereby electrically connecting the connected portion 12 and the electrode portion 14 adjacent thereto. A first fuse unit 10 to be
A second fuse portion 18 that connects the two is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film capacitor and a metallized film for manufacturing the same.

[0002]

2. Description of the Related Art In a general film capacitor, a pair of metallized films each having a metal vapor-deposited film formed on an insulating film are superimposed and wound in a column shape, and electrodes are sprayed on both ends of the column to form a metal-deposited film. Conduct with the membrane,
This is one in which a pair of terminals is formed.

Recently, in order to enhance the security of this type of film capacitor, a metal deposition film of at least one metallized film is divided by a non-deposition portion called a margin, thereby forming a large number of electrode portions, Techniques for forming a thin fuse portion connecting these electrode portions to terminals have been put to practical use. According to such a film capacitor with a security function, when a short circuit occurs between the metal-deposited films of the respective films, the fuse portion connected to the electrode portion including the short-circuit portion evaporates and cuts, and the power supply to the short-circuit portion is stopped. Safety is enhanced.

In this type of film capacitor with a security function, each time the fuse is blown, the electrode connected to the fuse is invalidated, and the capacitor capacity is reduced accordingly. Therefore, from the viewpoint of the stability of the capacitance of the capacitor, it is preferable that the decrease in the capacitance due to one operation of the fuse is small.

Therefore, Japanese Patent Application Laid-Open No. 4-225508 discloses
In Japanese Patent Application Laid-Open No. 7-86088 and the like, a metal deposition film is divided into a large number of rectangular electrode portions with a grid-like margin to reduce the size of each electrode portion and to mutually connect adjacent electrode portions. There has been proposed a film capacitor in which conduction is made through a thin fuse portion. According to such a capacitor, when a short circuit occurs in any one of the electrode portions, all the fuse portions connected to the electrode portion are blown, and only the electrode portion having the small area is electrically separated from the surroundings. The reduction in capacity will be small.

[0006]

By the way, in each of the above-mentioned film capacitors, the small size of the metal vapor-deposited film which is conducted directly to the terminal without passing through the fuse portion along the edge of the film on which the terminal is sprayed. Many regions are likely to occur. Since it cannot be said that a short circuit does not occur in these small regions, it is desirable to ensure security in such a case. In addition, in these small areas, sprayed metal particles often enter the inside from the edge, and the potential gradient is necessarily large at the boundary part connected to the terminal,
The occurrence rate of short circuits in the early stage of use is high, and it is important to ensure security even in a small area.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a film capacitor and a metallized film for the capacitor, which can achieve both stability and security of the capacitor capacity.

[0008]

In order to solve the above problems, a metallized film for a capacitor according to the present invention has an insulating film and a metal vapor-deposited film formed on the film. The deposited film has an edge section margin that partitions one side edge portion of the metal deposited film from the other portion of the metal deposited film as a connected portion, and a large number of metal deposited films in the other portion of the metal deposited film. An electrode section margin for partitioning the electrode section is formed, and further, a first fuse section for conducting the connected section and the other section and a second fuse section for conducting the electrode sections are formed. It is characterized by being.

[0009] A film capacitor according to the present invention is characterized in that the above-mentioned metallized film for a capacitor is the first, a metallized film for the first capacitor and a metallized film formed on an insulating film for a second capacitor. A metallized film is laminated, the connected portion of the first metallized film for a capacitor is connected to a first terminal, and a metal deposited film of the metallized film for a second capacitor is connected to a second terminal. . The type of capacitor may be a wound type in which two belt-shaped metallized films are stacked and wound, or a laminated type in which a large number of rectangular metalized films are alternately stacked.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] FIG. 1 is a developed view showing a first embodiment of a film capacitor according to the present invention. In this film capacitor 1, two equalized metallized films 2 (first and second metallized films) are stacked and wound in a cylindrical shape, electrodes 20 are welded to both ends of the cylindrical body, and further necessary terminals and exterior (Both not shown). However, instead of overlapping the same metallized film 2, a film having the same film width as the first film 2 and having no margins 8 and 16 described later may be used as the second metallized film. In this case, the same security can be obtained. The present invention is also applicable to a multilayer film capacitor in which a large number of metallized films 2 cut in a rectangular shape are alternately stacked.

The metallized film 2 is an insulating plastic film 3, a metal vapor-deposited film 4 formed on the plastic film 3, and a non-vapor-deposited portion for dividing the metal vapor-deposited film 4 into a plurality of regions. An edge section margin 8, an electrode section margin 16, and a vertical margin 6 are provided. The vertical margin 6 is a non-deposited portion formed to have a constant width along one side edge of the metallized film 2, and each metallized film 2 has a vertical margin 6.
Are turned to the opposite side, and the vertical margin 6 is shifted inward by a fixed distance from the edge of the other metallized film 2. Thereby, one welding electrode 20 is electrically connected to the end face of the metallized film 4 of the first metallized film, and the other welding electrode 20 is electrically connected to the end face of the metallized film 4 of the second metallized film. Moreover, the metal margins 4 are insulated from each other by the vertical margin 6.

The edge section margin 8 is formed by connecting the side edge portion of the metal deposition film 4 opposite to the vertical margin 6 to the connected portion 1 having a fixed width.
2 is for partitioning from the other portion of the metal deposition film 4, and is formed in a large number of dotted lines along a virtual line parallel to the side edge of the metal deposition film 4. Edge section margin 8
A certain gap is provided between the first fuse portion 1 and the first fuse portion 1 for electrically connecting the connected portion 12 to another portion of the metal deposition film 4 (that is, an electrode portion 14 described later).
It is 0.

Although the width of the first fuse portion 10 is not limited, it is generally preferably 0.05 to 5 mm, and more preferably 0.1 to 1.5 mm. If it is less than 0.05 mm, it is too sensitive and may be blown out immediately. If it is more than 5 mm, it is difficult to blow out and it is difficult to secure sufficient security.

The width of the line of the edge section margin 8 is not limited, but is usually preferably 0.05 to 3 mm, more preferably 0.1 to 2 mm, and still more preferably 0.2 to 2 mm. 1.5 mm. The line width is preferably uniform over the entire length, but may be partially non-uniform. When the width is smaller than 0.05 mm, it is difficult to form the edge section margin 8, and when the width is larger than 5 mm, the metal deposition film 4 is not formed.
Is not preferable from the viewpoint of securing the capacity.

A large number of cross-shaped electrode section margins 16 are formed over the entire surface of the metal deposition film 4 other than the portion to be connected 12. These electrode section margins 16 are arranged along a virtual grid line inclined at a fixed angle, for example, 45 ° with respect to the longitudinal direction of the film,
A lattice pattern is constituted as a whole. With these electrode division margins 16, the other portion of the metal deposition film 4 is divided into a large number of rectangular electrode portions 14 and second fuse portions 18 connected to four sides of each electrode portion 14. ing. In this embodiment, the electrode portion 14 has a square shape, but may have other shapes such as a rhombus, a parallelogram, a rectangle, and a trapezoid.

At a location adjacent to the edge section margin 8,
The shape of the electrode portion 14 is not a perfect square shape, but a triangular shape or a pentagonal shape with one corner of the square missing. A first fuse portion 10 is formed corresponding to each of the partially missing electrode portions 14, and each of the partially missing electrode portions 14 is connected to the connected portion 12 via the first fuse portion 10. Have been. Even if the first fuse portion 10 is not formed for all of the electrode portions 14 partially missing, all of the electrode portions 14
Can be secured, and the electrode portions 14 partially missing
May be formed with two or more first fuse portions 10.

If the margin 8 is not present, the partially missing electrode portion 14 is connected to the electrode 20 without any intervening fuse. If a short circuit occurs in the above, there is a possibility that security cannot be ensured. In contrast, in the present invention, the missing electrode portion 1
Since the first fuse portions 10 are also formed for each of the four, in the case of a short circuit, the first fuse portions 10 are blown and sufficient security can be secured.

The arrangement of the second fuse portions 18 is not limited to the illustrated example, and may be changed as appropriate. For example, in the illustrated example, the electrode unit 1
Although the second fuse portion 18 is formed at the center of the four sides of 4, the electrode portion 14 may be moved toward one of the vertices, or two or more fuse portions may be formed on one side of the electrode portion 14. It is also possible. Also, the second fuse unit 1
By making the width of 8 different from two or more types, the fusing current values of the four second fuse portions 18 connected to one electrode portion 14 may be made to be two or more types.

Although the width of the second fuse section 18 is not limited, it is generally 0.05 to 5 like the first fuse section 10.
mm is preferable, and more preferably 0.1 to 1.5 mm. If it is less than 0.05 mm, it is too sensitive and may be blown out immediately. If it is more than 5 mm, it is difficult to blow out and it is difficult to secure sufficient security.

Although the width of the line of the electrode section margin 16 is not limited, it is usually preferably 0.05 to 3 mm, more preferably 0.1 to 2 mm, like the edge section margin 8. More preferably 0.2 to 1.5 m
m. Although it is preferable that the width of the line is uniform over the entire length, it may be partially uneven. If the width is smaller than 0.05 mm, it is difficult to form the electrode section margin 16,
If the width is larger than 5 mm, the area of the metal deposition film 4 decreases, which is not preferable from the viewpoint of securing the capacity. The size of the electrode portion 14 is not limited, but generally, the length of one side of the electrode portion 14 is preferably 5 to 50 mm, more preferably 7 to 20 mm.

The shape of each end of the edge section margin 8 and the electrode section margin 16 may be a U-shape as shown in FIG. 1, a semicircle, or a triangular point. In each case, a similar effect can be obtained.

The material of the plastic film 3 is not limited, but is preferably made of one selected from polyethylene terephthalate, polypropylene, polystyrene, polycarbonate, polytetrafluoroethylene, and polyethylene, or laminated two or more kinds. The thickness is set as needed. The material of the metal deposition film 4 is not limited, but preferably, aluminum, zinc,
It is formed of one or two or more metals selected from copper or an alloy thereof, and the thickness is appropriately set as necessary.

According to the metallized film for a capacitor and the film capacitor having the above-described structure, the first fuse portion 10 is also formed on the electrode portion 14 adjacent to the connected portion 12, so that conventionally, security is considered. Even when a short circuit occurs in the partially missing electrode portion 14 that has not been performed, the first fuse portion 10 is blown and sufficient security can be secured.

[Second Embodiment] FIG. 2 is a developed view showing a second embodiment of the present invention. This embodiment is characterized in that cross-shaped electrode section margins 16 are formed along virtual grid lines that are parallel and perpendicular to the longitudinal direction of the film. Between the electrode portion 14 adjacent to the connected portion 12 and the connected portion 12, the edge section margin 8 and the first
The fuse section 10 is formed, and the first fuse section 10 electrically connects the end electrode section 14 and the connected section 12. In this case, the endmost electrode portion 14 is always rectangular. Other configurations are the same as those of the first embodiment, and the same effects as those of the first embodiment can be obtained by this embodiment.

[Third Embodiment] FIG. 3 is a developed view showing a third embodiment of the present invention. In this embodiment, the electrode section margins 16 are linear, are arranged at intervals along each of virtual grid lines inclined with respect to the film longitudinal direction, and the ends of the adjacent electrode section margins 16 are virtual. They are opposed to each other at lattice points. Thereby, each electrode portion 14 is placed at the position of each virtual grid point.
A second fuse portion 18 connecting the four corners is formed.

In the illustrated example, the end of the electrode section margin 16 is semicircular, but may be rectangular or triangular. Further, the widths of the four fuse portions belonging to one electrode portion 14 can be changed in two to four steps. Other configurations may be the same as in the first embodiment. In this embodiment, the same effect as in the previous embodiment can be obtained.

[Fourth Embodiment] FIG. 4 is a developed view showing a fourth embodiment of the present invention. In this embodiment, the electrode section margins 16 linearly arranged along each of virtual grid lines parallel and perpendicular to the film longitudinal direction are arranged, and a second electrode section margin 16 is provided between the ends of the adjacent electrode section margins 16. A fuse portion 18 is formed. Also, the connected part 1
An edge section margin 8 having the same length as the electrode section margin 16 is formed between the electrode section 14 and the connected section 12 adjacent to the second section 2. The first fuse portion 10 is formed so as to conduct the current. Other configurations may be the same as in the first embodiment. In this example, the same effects as in the above embodiments can be obtained.

[Fifth Embodiment] FIG. 5 is a developed view showing a fifth embodiment of the present invention. In this embodiment, the edge section margin 8 and the first fuse portion 10 of the fourth embodiment are
It is characterized in that it is formed in the same shape as the second embodiment. That is, each first fuse section 10 connects the center of one side of the end electrode section 14 to the connected section 12. Other configurations may be the same as in the first embodiment. In this example, the same effects as in the above embodiments can be obtained.

[Sixth Embodiment] FIG. 6 is a developed view showing a sixth embodiment of the present invention. In this embodiment, the shape of each electrode section margin 16 is H-shaped, and a relatively long linear shaft portion 16A and a relatively T-shaped formed at both ends of the shaft portion 16A are formed. And a short branch 16B. Each shaft portion 16A is arranged along an imaginary grid line forming a fixed angle (45 ° in the figure) with respect to the film longitudinal direction,
A substantially square electrode portion 14 is defined between these. The direction of the shaft portion 16A may be parallel or perpendicular to the longitudinal direction of the film, or may be an angle other than 45 °.

On the other hand, four branches 1 facing each other
A square-shaped fuse connection part 22 is defined between 6B. A second fuse portion 18 is formed between the ends of the branch portions 16B, and electrically connects the fuse connection portion 22 and the electrode portion 14. The widths of the second fuse portions 18 are equal in the illustrated example, but may be different from each other if necessary.

The length L2 of the branch portion 16B is preferably 0.6 to 100%, more preferably 2.5 to 30% of the length L1 of the shaft portion 16A. L2 is 1 of L1
If it is larger than 00%, the probability that self-healing occurs in the fuse connection portion 22 and the fuse function is not fulfilled increases. In addition, the self-healing is a function of recovering the insulation by evaporating the metal deposition film only at the short-circuit or discharge location without blowing the fuse when a slight short-circuit or corona discharge occurs. On the other hand, if it is less than 0.6%, it is difficult to obtain the effects of the present invention. In the case of a general metallized film, the length L1 of the shaft portion 16A is preferably 5 to 50 m.
m, more preferably 7 to 20 mm, and the length L2 of the branch portion 16B is preferably 0.3 to 10 mm, more preferably 0.5 to 3 mm, and still more preferably 0.5 to 2 mm. However, it is not limited to this range.

The area of the fuse connecting portion 22 is smaller than the area of the electrode portion 14, preferably 0.004 to 35% of the area of the electrode portion 14, more preferably 0.06 to 20%. . When comparing the two areas, since the area of the second fuse portion 18 can be almost ignored, the area is calculated with the margin center line as a boundary. The other configuration is the same as that of the first embodiment, and the sixth embodiment provides the same effects as those of the other embodiments described above.

In the sixth embodiment, the second fuse portions 18 can be separated from each other as compared with the third to fifth embodiments. And the possibility that the other second fuse portion 18 will be blown at the same time by the influence of heat can be reduced. further,
An excessive current flows to any one of the electrode portions 14 and the
Even if the second fuse portion 18 connected to No. 4 is blown,
Since the other three second fuse portions 18 connected to the same fuse connection portion 22 remain connected to each other via the fuse connection portion 22, in the electrode portion 14 adjacent to the short-circuited electrode portion 14, In each case, the state where the four second fuse portions 18 are effectively energized is maintained. Therefore, even when a weak electric shock, for example, a corona discharge or the like occurs to any of these electrode portions 14 thereafter,
Since the influence is distributed to the four second fuse portions 18, there is also an advantage that fuse blowing is less likely to occur.

[Seventh Embodiment] FIG. 7 is a developed view showing a seventh embodiment of the present invention. In the sixth embodiment, the branch portions 16B of the electrode section margin 16 are linear, but may be arc-shaped as in this embodiment. Also in this case, both ends of the branch portion 16B may have a U-shape as shown, or may have a semicircular shape. Other configurations are the first or sixth
It may be the same as the embodiment. In this case, the same effect as in the other embodiments can be obtained.

The shapes of the fuse connecting portion 22 and the second fuse portion 18 can be variously modified as shown in FIGS. 8 to 11 without being limited to the embodiment described above.
Instead of arranging the electrode section margins 16 in a grid to form a substantially square electrode section 14, the electrode section margins 16 are arranged in a substantially honeycomb shape as shown in FIG. 14 may be formed in large numbers. At both ends of the electrode section margin 16, a T-shaped branch portion 16B
Are formed, and the branch portions 16B of the three electrode section margins 16 are formed.
Face each other to define a circular fuse connection 22.

Although various embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various other modifications may be made as necessary. For example, in order to make the fusing current value of the second fuse portion 18 different, the fuse width may be changed or the thickness or material of the metal deposition film 4 may be locally changed.

[0037]

According to the metallized film for a capacitor and the film capacitor of the present invention, since the first fuse portion is formed also in the electrode portion adjacent to the connected portion, conventionally, security is considered. Even if a short circuit occurs at the endmost electrode portion that has not been made, the first fuse portion is blown and sufficient security can be secured.

[Brief description of the drawings]

FIG. 1 is a development view showing a film capacitor according to a first embodiment of the present invention.

FIG. 2 is a development view showing a film capacitor of a second embodiment.

FIG. 3 is a development view showing a film capacitor according to a third embodiment.

FIG. 4 is a development view showing a film capacitor of a fourth embodiment.

FIG. 5 is a development view showing a film capacitor of a fifth embodiment.

FIG. 6 is a development view showing a film capacitor of a sixth embodiment.

FIG. 7 is a development view showing a film capacitor of a seventh embodiment.

FIG. 8 is an enlarged view showing a modification of the second fuse section.

FIG. 9 is an enlarged view showing a modification of the second fuse section.

FIG. 10 is an enlarged view showing a modification of the second fuse section.

FIG. 11 is an enlarged view showing a modification of the second fuse section.

FIG. 12 is an enlarged view showing a modification of the second fuse section.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Film capacitor 2 Metallized film 4 Metal deposition film 6 Vertical margin 8 Edge division margin 10 1st fuse part 12 Connected part 16 Electrode division margin 16A Shaft part 16B Branch part 14 Electrode part 18 Second fuse part 20 Electrode 22 Fuse connection Department

Claims (4)

[Claims] An insulating film and a metal deposition film formed on the film, wherein the metal deposition film includes:
An edge division margin for dividing one side edge portion of the metal deposition film as a connected portion from another portion of the metal deposition film, and partitioning the metal deposition film into a number of electrode portions in the other portion of the metal deposition film. An electrode partition margin is formed, and further, a first fuse portion for conducting the connected portion and the other portion and a second fuse portion for conducting the electrode portions are formed. Metallized film for capacitors. 2. The metallized film for a capacitor according to claim 1, wherein the width of the first and second fuse portions is 0.05 to 5 mm. 3. The metallized film for a capacitor according to claim 1, wherein a plurality of the electrode portions are formed side by side in a width direction of the film. 4. A metallized film for a capacitor according to claim 1, wherein said metallized film for a capacitor is a first metallized film for a capacitor, and a metallized film is formed on said first metallized film for a capacitor and an insulating film. And a second metallized film for a capacitor formed by laminating the metallized film for a second capacitor, connecting the connected portion of the metallized film of the first metallized film for a capacitor to a first terminal, A film capacitor wherein a metal deposition film is connected to a second terminal.