Metallized film

Abstract

To prevent a capacitor from being cracked or damaged by suppressing a gas generation amount caused by evaporation and dispersion of a metal deposition film caused by a fusing operation within a proper range regarding a metalized film used for a film capacitor configured in a resin molded type with a maintenance mechanism.SOLUTION: A metal deposition film formed on a film surface of a dielectric film 2 is divided into large area divided electrodes (α1, α2 and α3) of a relatively large electrode area and small area divided electrodes (β1, β2 and β3) of a relatively small electrode area. A plurality of small area divided electrodes is disposed adjacently while holding an insulation slit therebetween in a parallel state, and a plurality of adjacent small area divided electrodes is electrically connected in common with respect to one large area divided electrode via a fuse consisting of the metal deposition film. A value obtained by dividing an area S of one large area divided electrode α1 by a width W of one fuse f1 is 1.5×102 or less.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a metallized film used for a resin-molded film capacitor, in which a metal vapor deposition electrode formed on the film surface of a dielectric film is partitioned into a large-area divided electrode and a small-area divided electrode, and a plurality of the small-area divided electrodes are arranged adjacent to each other with an insulating slit therebetween in a parallel state, and a plurality of adjacent small-area divided electrodes are commonly electrically connected to each one of the large-area divided electrodes through fuses (micro vapor deposition metal regions) made of a metal vapor deposition film.

Background Art

[0002] In a metallized film used for a resin-molded film capacitor, a safety mechanism including divided electrodes and fuses has been conventionally provided. When divided electrodes are formed in the metallized film, even when an insulation breakdown exceeding the self-healing function (self-healing) of the metallized film occurs, current flows into the divided electrode that has caused the insulation breakdown from the surrounding divided electrodes through the fuses, and by the fuse operation of evaporating and scattering the metal vapor deposition film of the fuses, the divided electrode that has caused the insulation breakdown is separated from other divided electrodes to recover insulation, and high safety can be ensured.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] In this type of film capacitor, in actual use, gas is generated due to the evaporation and scattering of the metal vapor deposition film of the fuse, accumulates in the mold resin, and the accumulated amount of the generated gas gradually increases over time. When the limit is reached, cracks, breakage, etc. are induced in the mold resin, leading to the problem of shortening the life of the capacitor (see, for example, Patent Documents 1, 2, and 3).

[0005] The present invention was created in view of such circumstances, and for a metallized film used in a resin mold type film capacitor and equipped with a safety mechanism having a divided electrode and a fuse as elements, the object is to suppress the gas generation amount as much as possible, and thereby prevent cracks, breakage, etc., and improve the capacitor life.

Means for Solving the Problems

[0006] The metallized film according to the present invention is The metal vapor deposition electrode formed on the film surface of the dielectric film is partitioned into a large-area divided electrode having a relatively large electrode area and a small-area divided electrode having a relatively small electrode area. A plurality of the small-area divided electrodes are arranged adjacent to each other with an insulating slit sandwiched therebetween in a parallel state. In the metallized film in which a plurality of adjacent small-area divided electrodes are commonly electrically connected to each large-area divided electrode via a fuse made of a metal vapor deposition film, The value obtained by dividing the area of one of the large-area divided electrodes by the width of one of the fuses is 1.5×10 2 or less, which is a feature.

[0007] In a film capacitor having the above-described pattern structure of a metallized film, when dielectric breakdown occurs in a certain small-area divided electrode and the current density flowing through a fuse from an adjacent large-area divided electrode to the small-area divided electrode becomes excessive and exceeds a predetermined value, the metal vapor deposition film forming the fuse evaporates and scatters. Due to this fuse operation, the small-area divided electrode that caused dielectric breakdown is separated from other divided electrodes, stopping the further progress of dielectric breakdown (recovery of insulation) and ensuring safety (safety function by fuse operation).

[0008] In the safety function based on this fuse operation, gas may be generated when the metal vapor deposition film evaporates and scatters. However, through various experiments, the inventor has found that, as in the above-described configuration of the present invention, the value obtained by dividing the area of the large-area divided electrode by the width of one of the fuses (hereinafter referred to as the "division value") is 1.5×10 2 The following can suppress the gas generation amount caused by the evaporation and scattering of the metal vapor deposition film due to the fuse operation to a safely appropriate low level. Here, the width of the fuse is the distance between the tip ends of a pair of insulating slits that sandwich the fuse between the longitudinal ends facing each other.

[0009] In the above division value "1.5×10 2 The "1.5" in "the following" indicates two significant figures, and its specific range is "145≦p<155".

[0010] The gas generation amount has a proportional relationship with the energy flowing from the large-area divided electrode to the small-area divided electrode through the fuse. The inflowing energy has a proportional relationship with the product of the area S of the large-area divided electrode as the inflow source and the square of the applied voltage. If the applied voltage is constant, the smaller the area S of the large-area divided electrode, the smaller the inflowing energy and the more the gas generation amount is suppressed. Looking at this from another perspective, the inflowing energy has a proportional relationship with the width W of the fuse formed in the insulating slit that partitions the large-area divided electrode and the small-area divided electrode. That is, the smaller the width W of the fuse, the more the gas generation amount is suppressed.

[0011] Summarizing the above correlation, the gas generation amount has a proportional relationship with respect to the area S of the large-area divided electrode, while also having a proportional relationship with respect to the width W of the fuse. Therefore, in order to control the gas generation amount caused by the evaporation and scattering of the metal deposition film due to the fuse operation to a suitably low level for safety, it is necessary that the value [S / W] obtained by dividing the value of the area S of the large-area divided electrode by the value of the width W of the fuse is within a predetermined range.

[0012] Based on the knowledge of this, the present invention has investigated the appropriate value of the division value [S / W], and as a result of various experiments, the value of the division value [S / W] is "1.5×10 2 or less" with two significant figures.

[0013] The metallized film of the present invention having the above configuration has several preferred embodiments or modified and deformed embodiments as follows.

[0014] 〔1〕That the large-area divided electrode and the small-area divided electrode are alternately arranged in the film width direction.

[0015] 〔2〕Also, that there are at least two sets in the film width direction of a set of a large-area electrode row region in which the large-area divided electrodes are arranged in parallel along the film longitudinal direction and a small-area electrode row region in which the small-area divided electrodes are arranged in parallel along the film longitudinal direction.

[0016] This is because the basic characteristic configuration of the present invention has two sets (two pairs) repeatedly, which will occupy most of the total area of the metallized film, so that the suppression of gas generation caused by the evaporation and scattering of the metal deposition film due to the fuse operation can be made sufficiently effective.

[0017] 〔3〕Further, the insulating slit between the pair of adjacent small-area divided electrodes is provided with a cut in the middle thereof, and a fuse for path expansion made of a metal deposition film is formed at the cut, electrically connecting the pair of small-area divided electrodes. In the case of this configuration, it is possible to secure more paths for the current flowing from the large-area divided electrode to the small-area divided electrode to flow out from the small-area divided electrode to another large-area divided electrode, and it becomes possible to achieve a further longer life of the capacitor.

Advantages of the Invention

[0018] According to the present invention, by setting the value obtained by dividing the area of the large-area divided electrode by the width of one of the fuses to 1.5×10 2 times or less, it is possible to suppress the amount of gas generated due to the evaporation and scattering of the metal deposition film caused by the fuse operation to a low level appropriate for safety. As a result, it is possible to suppress the amount of gas generated staying inside the resin-molded film capacitor within an appropriate range, and to achieve a longer life by preventing cracks, breakage, etc. of the capacitor.

Brief Description of the Drawings

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0020] Hereinafter, the metallized film used in the resin mold type film capacitor of the present invention having the above configuration will be described in detail at the level of specific examples in terms of its embodiments.

[0021] 〔First Embodiment〕 In the figure, 1 is a metallized film, 2 is a dielectric film (in FIG. 1, a state where a part of the metal vapor deposition electrode is peeled off is shown), 3 is a metal vapor deposition electrode made of a metal such as aluminum, zinc, or an alloy thereof, A1, A, 2, A3 are large-area electrode row regions constituting a part of the metal vapor deposition electrode 3, B1, B2, B3 are small-area electrode row regions constituting the remaining part of the metal vapor deposition electrode 3, z1 to z9 are insulating slits, α1, α2, α3 are large-area divided electrodes with relatively large electrode areas, β1, β2, β3 are small-area divided electrodes with relatively small electrode areas, f1, f2, f3 are fuses made of a metal vapor deposition film, 4 is an electrode lead-out connection part, and 5 is an insulating margin.

[0022] As shown in FIGS. 1 and 2, the metallized film 1 is obtained by forming a pattern of the metal vapor deposition electrode 3 on the surface of the dielectric film 2. The metal vapor deposition electrode 3 is composed of a set of three columns of large-area electrode row regions and small-area electrode row regions (A1, B1), (A2, B2), (A3, B3). A1 is the large-area electrode row region of the first row, and B1 is the small-area electrode row region of the first row. These constitute the set of the large-area electrode row region and small-area electrode row region of the first row (A1, B1). A2 is the large-area electrode row region of the second row, and B2 is the small-area electrode row region of the second row. These constitute the set of the large-area electrode row region and small-area electrode row region of the second row (A2, B2). A3 is the large-area electrode row region of the third row, and B3 is the small-area electrode row region of the third row. These constitute the set of the large-area electrode row region and small-area electrode row region of the third row (A3, B3). In this example, the repeated arrangement of the set of the large-area electrode row region and small-area electrode row region is three sets (three columns).

[0023] The large-area electrode row regions Ai (i = 1, 2, 3) are regions having, as their basic components, a plurality of large-area divided electrodes α1, α2, α3 formed by being divided by first insulating slits z1, z4, z7 arranged at predetermined intervals in the film longitudinal direction X. The small-area electrode row regions Bi (i = 1, 2, 3) are regions having, as their basic components, a plurality of small-area divided electrodes β1, β2, β3 formed by being divided by insulating slits (z2, z3), (z5, z6), (z8, z9) arranged at predetermined intervals in the film longitudinal direction X. And a set of the large-area electrode row regions and the small-area electrode row regions (Ai, Bi) is repeatedly arranged three sets along the film width direction Y. That is, the large-area electrode row region composed of the large-area divided electrodes and the small-area electrode row region composed of the small-area divided electrodes are alternately arranged in the film width direction Y. The metal deposition electrode 3 composed of the above three sets of the large-area electrode row regions and the small-area electrode row regions is formed on at least one side of the dielectric film 2 to constitute the metallized film 1.

[0024] In the above, the first insulating slit z1 is shorter than the second and third insulating slits z2, z3, and is also shorter than the fourth and seventh insulating slits z4, z7. The fourth insulating slit z4 has substantially the same length as the seventh insulating slit z7. The fifth and sixth insulating slits z5, z6 have substantially the same length with respect to the second and third insulating slits z2, z3. The eighth and ninth insulating slits z8, z9 have substantially the same length as the first insulating slit z1.

[0025] The shape of the large-area divided electrode α1 in the first column is a horizontally long rectangle, while the shapes of the large-area divided electrodes α2 and α3 in the second and third columns are vertically long rectangles. Here, the horizontally long direction is the film longitudinal direction X, and the vertically long direction is the film width direction Y. Although the shapes are different as described above, the areas of the large-area divided electrodes α2 and α3 in the second and third columns are approximately the same as the area of the large-area divided electrode α1 in the first column. The area of the large-area divided electrode α2 in the second column is approximately the same as the area of the large-area divided electrode α3 in the third column. Note that these area relationships may be the same.

[0026] The lengths of the fifth and sixth insulating slits z5 and z6 are approximately the same as the lengths of the second and third insulating slits z2 and z3. The lengths of the first, eighth, and ninth insulating slits z1, z8, and z9 are approximately half of the lengths of the second, third, fifth, and sixth insulating slits z2, z3, z5, and z6. The length of the fourth insulating slit z4 is approximately the same as the length of the seventh insulating slit z7 and is approximately twice the lengths of the first, eighth, and ninth insulating slits z1, z8, and z9.

[0027] Hereinafter, the pattern structure of the metallized film will be described in more detail.

[0028] The large-area electrode row region A1 in the first column includes an electrode lead-out connection portion 4 for connecting a metal spraying electrode (metallikon) at one edge in the film width direction Y of the metallized film 1. This electrode lead-out connection portion 4 is a region that continuously expands along the film longitudinal direction X at one edge in the film width direction Y (a horizontally long conductor region outside the broken line in FIG. 1) and is integrally connected to the large-area electrode row region A1 in the first column. The electrode thickness of the electrode lead-out connection portion 4 is thicker (heavy edge) compared to other regions of the metal vapor deposition electrode 3. Therefore, the connection reliability between the electrode lead-out connection portion 4 and the electrode lead-out portion (metallikon) 9 is high.

[0029] The large-area electrode row region A1 in the first column is an aggregate of a large number of large-area divided electrodes α1... arranged in parallel along the film longitudinal direction X. The large-area divided electrodes α1, α1... adjacent to each other in the film longitudinal direction X are partitioned by first insulating slits z1... extending in the film width direction Y.

[0030] The small-area electrode row region B1 in the first column is an aggregate of a large number of small-area divided electrodes β1... arranged in parallel along the film longitudinal direction X. The number of the small-area divided electrodes β1... is eight times the number of the large-area divided electrodes α1... (illustrative example in the figure). The small-area divided electrodes β1, β1... adjacent to each other in the film longitudinal direction X are partitioned by second and third insulating slits z2, z3... extending in the film width direction Y. The second insulating slit z2 has a shape that is linearly continuous over the entire length of the long side direction of the small-area divided electrode β1. The third insulating slit z3 has cuts provided at two positions in the long side direction. The small-area divided electrodes β1... are electrically connected to the large-area divided electrodes α1, α2 in the large-area electrode row regions A1, A2 of the first and second columns, respectively, via fuses f1, f1 made of a metal deposition film at both end portions in the long side direction. At the cut portion of the third insulating slit z3 that is located skipping one between the small-area divided electrodes β1, β1... adjacent to each other in the film longitudinal direction X, there are fuses f 12 , f 13 formed by a metal deposition film.

[0031] Both the second and third insulating slits z2, z3 are formed in a Müller-Rear shape (a shape having inward-facing arrow feathers at both ends of a line segment of a predetermined length). And the row region of the arrow feather groups that are neatly arranged in a row adjacent to and facing each other in the film longitudinal direction X demarcates the boundary between the large-area electrode row region A1 in the first column and the small-area electrode row region B1 in the first column, while forming a regular arrangement of the fuse f1... groups between adjacent arrow feathers. The large-area divided electrode α1 in the first column and a large number of small-area divided electrodes β1... are electrically connected via the fuse f1... group in the upper row. Further, a large number of small-area divided electrodes β1... are electrically connected to the large-area divided electrode α2 in the second column via the fuse f1... group in the lower row.

[0032] The large-area electrode row region A2 in the second column is an aggregate of a number of large-area divided electrodes α2... arranged in a parallel state along the film longitudinal direction X. The adjacent large-area divided electrodes α2, α2... in the film longitudinal direction X are separated by insulating slits z4... extending in the film width direction Y.

[0033] The small-area electrode row region B2 in the second column is an aggregate of a number of small-area divided electrodes β2... arranged in a parallel state along the film longitudinal direction X. The number of small-area divided electrodes β2... is four times the number of large-area divided electrodes α2... in the large-area electrode row region A2 in the second column (illustrative example in the figure). The adjacent small-area divided electrodes β2, β2... in the film longitudinal direction X are separated by the fifth and sixth insulating slits z5, z6... extending in the film width direction Y. The fifth insulating slit z5 has a shape that is linearly continuous over the entire length in the long side direction of the small-area divided electrode β2. The sixth insulating slit z6 has cuts provided at two locations in the long side direction. The small-area divided electrodes β2... are electrically connected to the large-area divided electrodes α2, α3 in the large-area electrode row regions A2, A3 in the second and third columns via fuses f2, f2 made of a metal deposition film at both ends in the long side direction. At the cut portion of the sixth insulating slit z6 located skipping one position between adjacent small-area divided electrodes β2, β2... in the film longitudinal direction X, there are fuses f 22 , f 23 formed by a metal deposition film.

[0034] The large-area electrode row region A3 in the third column is an aggregate of a number of large-area divided electrodes α3... arranged in a parallel state along the film longitudinal direction X. The adjacent large-area divided electrodes α3, α3... in the film longitudinal direction X are separated by the seventh insulating slit z7... extending in the film width direction Y.

[0035] In the small-area electrode row region B3 in the third column, its eighth and ninth insulating slits z8 and z9 are connected to the insulating margin 5 at the other edge in the film width direction Y of the metallization film 1. This insulating margin 5 is a horizontally elongated insulating region that extends continuously in the film longitudinal direction X at the other edge in the film width direction Y of the dielectric film 2.

[0036] The small-area electrode row region B3 in the third column is an aggregate of a large number of small-area divided electrodes β3... arranged in parallel along the film longitudinal direction X. The number of small-area divided electrodes β3... is four times the number of large-area divided electrodes α3... in the large-area electrode row region A3 in the third column (illustrative example in the figure). Adjacent small-area divided electrodes β3 and β3... in the film longitudinal direction X are partitioned by the eighth and ninth insulating slits z8 and z9... extending in the film width direction Y. The eighth insulating slit z8 has a shape that is linearly continuous over the entire length of the long side direction of the small-area divided electrode β3. The ninth insulating slit z9 has a cut provided at one location in the long side direction. The small-area divided electrode β3... is electrically connected, via a fuse f3 made of a metal deposition film, to the large-area divided electrode α3 in the large-area electrode row region A3 in the third column at one end of its long side direction. At the cut portion of the insulating slit z9 that is located skipping one between adjacent small-area divided electrodes β3 and β3... in the film longitudinal direction X, a fuse f 32 formed of a metal deposition film is formed.

[0037] In the metallization film of this embodiment, the metal deposition electrodes 3 formed on the film surface of the dielectric film 2 are partitioned into large-area divided electrodes (α1, α2, α3)... and small-area divided electrodes (β1, β2, β3).... A plurality of the small-area divided electrodes (β1, β2, β3) are arranged adjacent to each other in parallel with the insulating slits (z2, z3), (z5, z6), (z8, z9) therebetween, and a plurality of adjacent small-area divided electrodes (β1, β2, β3) are commonly electrically connected to each large-area divided electrode (α1, α2, α3) via fuses (f1, f2, f3) made of a metal deposition film.

[0038] In addition, the small-area divided electrode β1 in the small-area electrode row region B1 of the first column is connected to the large-area divided electrode α1 in the large-area electrode row region A1 of the first column and the large-area divided electrode α2 in the large-area electrode row region A2 of the second column via the fuses f1, f1 at both end portions in the film width direction Y, respectively. Further, the small-area divided electrode β2 in the small-area electrode row region B2 of the second column is connected to the large-area divided electrode α2 in the large-area electrode row region A2 of the second column and the large-area divided electrode α3 in the large-area electrode row region A3 of the third column via the fuses f2, f2 at both end portions in the film width direction Y, respectively. Furthermore, the small-area divided electrode β3 in the small-area electrode row region B3 of the third column is connected to the large-area divided electrode α3 in the large-area electrode row region A3 of the third column via the fuse f3 at one end portion in the film width direction Y. The other end portion of the small-area divided electrode β3 in the film width direction Y is electrically closed by the insulating margin 5.

[0039] The first insulating slit z1 in the large-area electrode row region A1 of the first column that partitions the adjacent large-area divided electrodes α1, α1 is linearly continuous with respect to the second insulating slit z2 having a linearly continuous shape in the small-area electrode row region B1 of the first column. The fourth insulating slit z4 in the large-area electrode row region A2 of the second column that partitions the adjacent large-area divided electrodes α2, α2 is linearly continuous with respect to each of the second insulating slit z2 having a linearly continuous shape in the small-area electrode row region B1 of the first column and the fifth insulating slit z5 having a linearly continuous shape in the small-area electrode row region B2 of the second column. The seventh insulating slit z7 in the large-area electrode row region A3 of the third column that partitions the adjacent large-area divided electrodes α3, α3 is linearly continuous with respect to each of the fifth insulating slit z5 having a linearly continuous shape in the small-area electrode row region B2 of the second column and the eighth insulating slit z8 having a linearly continuous shape in the small-area electrode row region B3 of the third column.

[0040] The insulating slit z1 is at the same position as the insulating slits z5, z7, and z8 in the longitudinal direction X of the film. The insulating slit z4 is at the same position as the insulating slits z2, z5, and z8 in the longitudinal direction X of the film. The insulating slits z3, z6, and z9 are at the same position in the longitudinal direction X of the film. The pitch of the first insulating slit z1 is four times the pitch of the second insulating slit z2 and the pitch of the third insulating slit z3. The pitches of the fourth and seventh insulating slits z4 and z7 are twice the pitch of the insulating slits z2, z5, and z8.

[0041] A pair of adjacent small-area divided electrodes β1, β1 sandwiching the second insulating slit z2 are not directly connected, but are connected via the upper fuse f1 and the large-area divided electrode α1, and also via the lower fuse f1 and the large-area divided electrode α2. The same applies to a pair of adjacent small-area divided electrodes β2, β2 sandwiching the fifth insulating slit z5. A pair of adjacent small-area divided electrodes β3, β3 sandwiching the eighth insulating slit z8 (excluding the insulating slit continuous with the seventh insulating slit z7) are not directly connected, but are connected via the upper fuse f3 and the large-area divided electrode α3.

[0042] A pair of adjacent small-area divided electrodes β1, β1 sandwiching the third insulating slit z3 are directly connected via the path-expanding fuses f 12 , f 13 . A pair of adjacent small-area divided electrodes β2, β2 sandwiching the sixth insulating slit z6 are directly connected via the path-expanding fuses f 22 , f 23 . A pair of adjacent small-area divided electrodes β3, β3 sandwiching the ninth insulating slit z9 are directly connected via the path-expanding fuse f 32 .

[0043] Next, with reference to FIG. 3, the width W of the fuse f1 (f2, f3) connecting the large-area divided electrode α1 (α2, α3) and the small-area divided electrode β1 (β2, β3) will be described.

[0044] The fuse f1 is formed by a metal deposition film between the tip of the insulating slit z2 (specifically, the tip z2' of the arrow root) and the tip of the insulating slit z3 adjacent thereto (z3' as above). The width W of the fuse f1 sandwiched between these two tips is the minimum distance between the tip z2' of the insulating slit z2 and the tip z3' of the insulating slit z3.

[0045] Prepare two sheets of the metallized film 1 configured by forming the metal deposition electrode 3 on the dielectric film 2 as described above. As shown in FIG. 4, with the two sheets of the metallized films 1, 1 in an inverted state by 180°, shift them slightly in the film width direction Y so that the electrode lead-out connection part 4 of one metallized film 1 does not overlap with the metal deposition electrode of the other metallized film 1, and stack them in two layers, one on top of the other. For the first-row large-area electrode row region A1 along the side edge of the upper metallized film 1, the third-row small-area electrode row region B3 of the lower metallized film 1 directly below it faces. The electrode lead-out connection part 4 faces the insulating margin 5. The second-row large-area electrode row region A2 in the upper metallized film 1 faces the second-row small-area electrode row region B2 in the lower metallized film 1. The third-row large-area electrode row region A3 in the upper metallized film 1 faces the first-row small-area electrode row region B1 in the lower metallized film 1. Also, the first-row small-area electrode row region B1 in the upper metallized film 1 faces the third-row large-area electrode row region A3 in the lower metallized film 1. The second-row small-area electrode row region B2 in the upper metallized film 1 faces the second-row large-area electrode row region A2 in the lower metallized film 1. For the third-row small-area electrode row region B3 of the upper metallized film 1, the first-row large-area electrode row region A1 at the side edge of the lower metallized film 1 directly below it faces. The insulating margin 5 faces the electrode lead-out connection part 4. In short, the small-area electrode row region in one metallized film faces the large-area electrode row region in the other metallized film.

[0046] Since there is a risk of short - circuit failure when the large - area electrode row region in one metallized film faces the large - area electrode row region in the other metallized film, it is preferable that all of the large - area electrode row region in one metallized film faces the small - area electrode row region in the other metallized film.

[0047] In the state where the upper metallized film 1 and the lower metallized film 1 are overlapped as described above, as shown in FIG. 5, they are wound multiple times around the outer peripheral portion of the core 6, and further, after winding the outer packaging film 7 around the outermost layer, it is flattened into an elongated oval shape as shown in the figure by pressing to obtain a multilayer metallized film 8. Further, electrode lead - out portions (metallikon) 9, 9 are formed by metal spraying at both axial ends of the multilayer metallized film 8 to obtain a highly flattened metallized film capacitor element C. The electrode lead - out portions 9, 9 are electrically connected to the electrode lead - out connection portions 4, 4 on both axial sides. The metallized film capacitor element C configured in this way is, for example, housed in a resin case and sealed with a filling resin that fills the resin case except for the electrode lead - out terminal portions connected to the external terminals.

[0048] Note that, instead of winding the long metallized films 1, 1 stacked in two layers as described above, there is also a type of capacitor element in which short metallized films 1, 1 stacked in two layers are laminated.

[0049] Next, the division value, which is the greatest feature of the present invention in this embodiment, will be described.

[0050] The division value, which is a characteristic element of the present invention, is the value obtained by dividing the area S of the large - area divided electrode αi (in the embodiment, i = 1, 2, 3) by the width W of the fuse fi (in the embodiment, i = 1, 2, 3). In particular, it refers to the value obtained by dividing the area S of the large - area divided electrode α1 in the first - row large - area electrode row region A1 connected to the electrode lead - out connection portion 4 by the width W of the fuse f1 in the small - area divided electrode β1 in the first - row small - area electrode row region B1.

[0051] Regarding the value [S / W] obtained by dividing the area S of the large-area divided electrode α1 by the width W of the fuse f1, in this embodiment, this value is set to approximately 150 ([S / W] = 150). More specifically, S = 24 mm × 9.45 mm = 226.8 mm 2 W = 1.5 mm S / W = 226.8 / 1.5 = 151.2 That is.

[0052] As a result, in the case of the embodiment of FIG. 1, in the resin-molded film capacitor, cracks, breakage, etc. could be prevented. This means that the amount of gas generated due to the evaporation and scattering of the metal vapor deposition film caused by the fuse operation could be suppressed within a safe and appropriate range, and it became possible to extend the life of the film capacitor.

[0053] 〔Second Embodiment〕 In the second embodiment (not shown) formed in a pattern similar to the pattern of FIG. 1, the division value [S / W] was set to approximately 120. Specifically, S = 24 mm × 9.45 mm = 226.8 mm 2 W = 1.9 mm S / W = 226.8 / 1.9 ≒ 119.4 As in the case of the embodiment of FIG. 1, in the resin-molded film capacitor, cracks, breakage, etc. could be prevented. This also means that the amount of gas generated due to the evaporation and scattering of the metal vapor deposition film caused by the fuse operation could be suppressed within a safe and appropriate range, and it became possible to extend the life of the film capacitor.

[0054] 〔Third Embodiment〕 In the third embodiment shown in FIG. 6, the metal vapor deposition electrode 3 is composed of two sets of large-area electrode row regions and small-area electrode row regions (A1, B1), (A3, B3). The set (A2, B2) in the middle second row in FIG. 1 is excluded. Although the number of sets is two, for convenience, the set (A3, B3) is given the reference numeral for the one in the second row. This is because importance is attached to the similarity of the morphological surface of the pattern.

[0055] In this third embodiment, with respect to a pair of first insulating slits z1, z1 adjacent to each other in the large-area divided electrode α1 of the first embodiment shown in FIG. 1, a further first insulating slit z1 is added at the central position thereof. The large-area divided electrode α1 is vertically long. In the case of FIG. 1, eight small-area divided electrodes β1 corresponded to the large-area divided electrode α1, whereas in the case of FIG. 6, four small-area divided electrodes β1 correspond to the large-area divided electrode α1.

[0056] In the case of FIG. 6, the lateral width (film longitudinal direction X) of the large-area divided electrode α1 is about half that in the case of FIG. 1. On the other hand, the longitudinal width (film width direction Y) of the large-area divided electrode α1 is about twice that in the case of FIG. 1, and the area of the large-area divided electrode α1 is substantially the same in FIGS. 6 and 1. Since the width W of the fuse f1 is the same, the value [S / W] obtained by dividing the area S of the large-area divided electrode α1 by the width W of the fuse f1 is about 145. More specifically, S = 12 mm × 18 mm = 216 mm 2 W = 1.5 mm S / W = 216 / 1.5 = 144 That is.

[0057] As a result, in the case of the third embodiment, in the resin mold type film capacitor, cracks, breakage, etc. could be prevented. This means that the amount of gas generated due to the evaporation and scattering of the metal vapor deposition film by the fuse operation could be suppressed within a safe and appropriate range, and it became possible to extend the life of the film capacitor.

[0058] 〔Comparative Example〕 On the other hand, in the case of a metallized film where the value [S / W] obtained by dividing the area S of the large-area divided electrode α1 by the width W of the fuse f1 exceeds 1.5×10 2 it is impossible to sufficiently suppress the gas generation caused by the evaporation and scattering of the metal vapor deposition film due to the fuse operation within a range appropriate for safety. For example, in the metallized film 1 having a pattern structure set with S / W = 200, obvious cracks were recognized in the case in which the metallized film capacitor element C was housed and resin-sealed due to the gas generation caused by the evaporation and scattering of the metal vapor deposition film due to the fuse operation.

[0059] In the above embodiment, it was explained that fuses f 12 , f 13 for path expansion by a metal vapor deposition film are formed at the cut portions of the third insulating slit z3 that are located skipping one between the adjacent small-area divided electrodes β1, β1,... in the film longitudinal direction X.

[0060] Now, as shown in FIG. 7, assume that dielectric breakdown has occurred at point P in a certain small-area divided electrode β1. Since the resistance value of the dielectric breakdown location P is significantly reduced, large currents i1, i 2 , i3, i4 flow in rapidly from the periphery, and clearing is performed by the evaporation and scattering of the metal vapor deposition film. Current i1 flows in from the upper fuse f1, current i 2 flows in from the lower fuse f1, current i3 flows in from the upper fuse f1 and the upper fuse f 12 for path expansion, and current i4 flows in from the lower fuse f1 and the lower fuse f 13 for path expansion.

[0061] When the clearing ends, the large current disappears and returns to the steady state. As shown in FIG. 8, even if the large current flowing into the dielectric breakdown location P becomes excessive, the excessive current can be discharged to the large-area divided electrode α1 or the large-area divided electrode α2 through the upper fuse f 12 for path expansion or the lower fuse f 13 for path expansion.

[0062] In this way, the excessive current is dispersed into small currents and flows out to the large-area divided electrodes α1 and α2. Therefore, the clearing inside the small-area divided electrode β1 is one unit electrode region β including the insulation breakdown point P. 1-1 Except for 1- 2 , β 1-3 , β 1-4 , β 1-5 , β 1-6 , no breakdown occurs.

[0063] In conclusion, in the small-area divided electrode β1 where insulation breakdown has occurred, the area ratio where the capacitance formation function disappears is about one-sixth (the remaining about five-sixths remains as the effective electrode area), which is significantly reduced.

[0064] In this way, by providing the path expansion fuses f 12 , f 13 in the middle of the insulation slit, it is possible to suppress the decrease in the effective electrode area and thus the disappearance of the capacitance formation function, improve the capacitor life, and improve the withstand voltage performance.

Industrial Applicability

[0065] The present invention relates to a metallized film used in a film capacitor configured in a resin mold type and equipped with a safety mechanism having divided electrodes and fuses. It is useful as a technique for suppressing the amount of gas generated due to the evaporation and scattering of the metal vapor deposition film caused by the fuse operation within an appropriate range and preventing cracks and breakages of the capacitor.

Explanation of Signs

[0066] 2 Dielectric film 3 Metal vapor deposition electrode A1, A2, A3 Large-area electrode row regions B1, B2, B3 Small-area electrode row regions α1, α2, α3 Large-area divided electrodes β1, β2, β3 Small-area divided electrodes f1, f2, f3 Fuses f 12, f 13 Fuse for path expansion f 22 , f 23 Fuse for path expansion f 32 Fuse for path expansion zi (i = 1, 2…) Insulation slit

Claims

1. The metal vapor deposition electrode formed on the film surface of the dielectric film is partitioned into a large-area divided electrode with a relatively large electrode area and a small-area divided electrode with a relatively small electrode area, a plurality of the small-area divided electrodes are arranged adjacent to each other with an insulating slit therebetween in a parallel state, in the metallized film in which a plurality of adjacent small-area divided electrodes are commonly electrically connected to each large-area divided electrode through a fuse made of a metal vapor deposition film, a metallized film characterized in that a value obtained by dividing the area of one large-area divided electrode by the width of one fuse is 119.4 or more and 151.2 or less.

2. The metallized film according to Claim 1, wherein the large-area divided electrode and the small-area divided electrode are alternately arranged in the film width direction.

3. The metallized film according to Claim 2, having at least two sets in the film width direction of a set of a large-area electrode row region in which the large-area divided electrodes are arranged in parallel along the film longitudinal direction and a small-area electrode row region in which the small-area divided electrodes are arranged in parallel along the film longitudinal direction.

4. The insulating slit between a pair of adjacent small-area divided electrodes arranged adjacent to each other is provided with a cut in the middle thereof, and a fuse for path expansion made of a metal vapor deposition film is formed at the cut, and the pair of small-area divided electrodes are electrically connected to each other. The metallized film according to any one of Claims 1 to 3.

Images