JP5395302B2 - Metallized film capacitors - Google Patents

Description

  The present invention relates to a metallized film capacitor used for smoothing and filtering inverter circuits for industrial equipment and automobiles.

  The conventional metallized film capacitor has a metallized near-metallized vapor deposition electrode 2 on the polypropylene film 1 shown in FIG. 1 thick and a non-metallized vapor-deposited electrode 3 thinly deposited, and an insulating margin 4 is formed at the end facing the metallicon. Film is being used. This metallized film capacitor has a self-healing function for recovering the insulation of the dielectric breakdown part due to scattering of the vapor deposition electrode around the dielectric breakdown part by the discharge energy at the time of dielectric breakdown of the polypropylene film. However, at high temperatures and high voltages, the number of dielectric breakdowns increases, so that the self-recovery function cannot be obtained sufficiently, and the capacitor may reach the short mode. For example, as shown in FIG. 10, in a metallized film capacitor in which a metallized film having a vapor-deposited metal film is laminated and wound on a dielectric (plastic film), the dielectric is shown at the x mark in the drawing. When the body breaks down and self-healing (spattering of the deposited metal) is insufficient, it is conducted with the deposited metal on the metallized film disposed under the metallized film via the broken dielectric part. Become.

  The smoothing capacitor of the inverter circuit is used at a high temperature and a high voltage, and has a strong demand for safety, and a metallized film in which the vapor deposition electrode is divided into a plurality of parts is employed (see, for example, Patent Documents 1 to 3). Examples of metallized films on which such divided electrodes are formed are shown in [FIG. 2-A] to [FIG. 2-C].

  In FIG. 2A, an insulating margin 12 is formed at the end of the metallized film facing the metallicon connection portion 10 in the width direction, and the divided electrode 7 is formed by the width direction insulating slit 5 and the longitudinal direction insulating slit 6. Is formed. These divided electrodes 7 are connected in parallel by a fuse 8. Further, the vapor deposition electrode in the vicinity of the metallicon has a configuration in which the metallicon connection portion 10 and the divided electrode 7 are separated by a longitudinal insulating slit 9, and the metallicon connection portion 10 and the divided electrode 7 are connected by a fuse 11.

  In FIG. 2B, an insulating margin 12a is formed at the end of the metallized film that faces the metallicon connecting portion 10a in the width direction, and a honeycomb-shaped divided electrode 7a is formed by the Y-shaped insulating slit 13a. . These divided electrodes 7a are connected in parallel by a fuse 8a.

  In FIG. 2C, an insulating margin 12b is formed at the end of the metallized film facing the metallicon connecting portion 10b in the width direction, and a honeycomb-shaped divided electrode 7b is formed by the Mueller-rear insulating slit 14a. ing. These divided electrodes 7b are connected in parallel by a fuse 8b.

  When a dielectric breakdown occurs in a metallized film capacitor using a metallized film having such divided electrodes, it has the above-described self-healing function. At the same time, even when a breakdown that exceeds the self-healing function of the metallized film capacitor occurs, current flows from the surrounding split electrode to the split electrode where the breakdown occurs, causing the vapor deposition electrode of the fuse part to scatter, causing breakdown. The generated divided electrode is separated from other divided electrodes to have a function of restoring insulation, and high safety is ensured.

  Furthermore, if the area of the divided electrode is reduced, the capacity reduction due to the fuse operation can be suppressed, and the life of the capacitor can be extended. However, if the material is too finely divided, the energy of the divided electrodes becomes small, and when a dielectric breakdown occurs, the fuse operation becomes difficult and the safety of the capacitor decreases. This phenomenon becomes more prominent as the temperature increases.

  Further, when the divided electrode area is reduced, the number of fuses is increased. However, since the fuse has a higher resistance than the divided electrode, it is reported that the heat generation of the capacitor increases (for example, patents). Reference 4). Such an increase in self-heating causes a decrease in withstand voltage performance and safety performance. Particularly in the center of the capacitor element, the temperature rises most due to self-heating, and the withstand voltage performance and the safety performance are deteriorated more than other portions.

  Therefore, in order to improve the above-described problems, a means has been devised in which divided electrode portions and electrodes that are not divided and have a large area (non-divided electrode portions) are collectively arranged (see, for example, Patent Document 5). In the metallized film capacitor described in Patent Document 5, a plurality of divided electrodes divided by slits are provided on the insulating margin side, and a non-divided electrode portion is provided on the terminal connection side (metallicon connection side). And the some division | segmentation electrode is comprised so that the area of a vapor deposition electrode may become small as it approaches an insulation margin.

Japanese Patent Laid-Open No. 08-250367 Japanese Patent Laid-Open No. 11-26281 JP-A-11-26280 JP 2003-338422 A JP 2005-12082 A

  By the way, capacitors used for smoothing an inverter circuit for automobiles are used at high temperatures, high frequencies, and high voltages, and miniaturization and high safety are required. For this reason, it is necessary to reduce the thickness of the dielectric film to reduce the size of the capacitor and to improve the withstand voltage performance and safety in the high temperature region.

  However, in the metallized film capacitor described in Patent Document 5, the divided electrode portions (small divided electrode portions) in which the divided electrodes having a relatively small electrode area are arranged in the longitudinal direction are gathered on the insulation margin side, while the terminal connection side Since the divided electrode portion (large divided electrode portion) and the non-divided electrode portion in which divided electrodes having a relatively large electrode area are arranged in the longitudinal direction are arranged, safety at high temperatures is always sufficiently ensured. The situation was not up. Specifically, when a dielectric breakdown occurs in the small divided electrode part, sufficient current does not flow from the divided electrode adjacent to the divided electrode constituting the small divided electrode part where the dielectric breakdown occurs, In particular, there is a possibility that the fuse cannot be operated at a high temperature.

  Also, it is necessary to apply masking oil to the metallized film in order to form the divided electrode (divide the electrode by the insulating slit), but the remaining masking oil adhered during vapor deposition affects the small divided electrode part and the large divided electrode. There was a difference in the slipperiness of the metallized film between the part and the non-divided electrode part.

  However, in the metallized film capacitor described in Patent Document 5, the non-divided electrode portion, the large divided electrode portion, and the small divided electrode portion are arranged in the width direction from the insulation margin side to the terminal connection portion side in this order. The position of the insulating slit on the fluorinated film was greatly biased in the width direction. As a result, the slidability of the metallized film is remarkably different in the width direction, and when the metallized film is wound, the element winding state varies, which may affect the voltage resistance at high temperatures.

  This invention is made | formed in view of the said subject, and it aims at providing the metallized film capacitor which has the favorable safety | security at high temperature and withstand voltage property.

  The present invention relates to a metallization in which a capacitor element is formed by winding or laminating a metallized film provided with a vapor deposition electrode on at least one surface of a dielectric film, and a metallicon for electrode drawing is connected to both end surfaces of the capacitor element. A film capacitor, wherein the vapor deposition electrode is divided by insulating slits arranged at intervals in the longitudinal direction of the metallized film, and a plurality of first divided electrodes are formed along the longitudinal direction; Largely formed along the longitudinal direction are a plurality of second divided electrodes having a larger electrode area than the first divided electrode, in which the vapor deposition electrode is divided by insulating slits arranged at intervals in the longitudinal direction of the metallized film. Each of the plurality of first divided electrodes is arranged adjacent to each other alternately in the width direction of the metallized film. Is characterized in that it is connected to the second divided electrodes in the first divided electrode is formed between the longitudinal direction to sandwich the insulating slit fuse.

  According to the invention thus configured, each of the plurality of first divided electrodes having a relatively small electrode area is connected to the second divided electrode having a relatively large electrode area by the fuse. Then, in the width direction of the metallized film, such a small divided electrode portion constituted by a plurality of first divided electrodes is disposed adjacent to a large divided electrode portion constituted by a plurality of second divided electrodes. ing. For this reason, at least one end of the first divided electrode is connected to the second divided electrode having a larger electrode area than the first divided electrode via a fuse, so that dielectric breakdown occurs at the first divided electrode. Even if a failure occurs, a sufficient current flows to operate the fuse from the second divided electrode adjacent to the first divided electrode, and the fuse operates reliably (the vapor deposition electrode of the fuse portion is scattered) to insulate the fuse. It is possible to separate the divided electrodes that have broken down. Thereby, stable security can be obtained even if the divided electrodes are made smaller.

  Further, since the small divided electrode portions and the large divided electrode portions are alternately arranged in the width direction of the metallized film, the position of the insulating slit on the metallized film is prevented from being unevenly distributed in the width direction, and the metal It is possible to level the slidability of the plasticized film in the width direction. As a result, when the metallized film is wound, it is possible to suppress variation in the element winding state, and to ensure good voltage resistance at high temperatures. Therefore, it is possible to provide a metallized film capacitor having good safety and voltage resistance at a high temperature (for example, a temperature exceeding 100 ° C.).

  Here, by reducing the interval between the insulating slits arranged in the small divided electrode portion as compared with the interval between the insulating slits arranged in the large divided electrode portion, the first length is suppressed while suppressing the film from becoming longer in the width direction. The area of the divided electrode can be made smaller than the area of the second divided electrode.

  Furthermore, it is preferable to arrange a large-divided electrode part on the metallicon connection part side of the metallized film for electrode drawing. This is because when the small divided electrode portion is arranged on the metallicon connection portion side and the dielectric breakdown occurs in the first divided electrode constituting the small divided electrode portion, the first divided electrode and the second divided electrode are arranged. When the fuse connecting the two operates, the current path from the first divided electrode is completely cut off and may not function as a capacitor. On the other hand, by arranging the large divided electrode portion on the metallicon connection portion side, the second divided electrode on the electrode lead-out side (the second divided electrode portion formed on one of the pair of metallized films) Even when dielectric breakdown occurs in the split electrode), the first split electrode formed on the opposing metallized film (the other metallized film of the pair of metallized films) and adjacent to the first split electrode By operating the fuse that connects the second divided electrode, an electrode region that functions as a capacitor can be left.

  According to the present invention, it is possible to provide a metallized film capacitor having good safety and voltage resistance at high temperatures.

It is a figure which shows the laminated constitution of the metallized film currently used for the conventional metallized film capacitor. It is a top view which shows the conventional metallized film provided with the division | segmentation electrode, [FIG. 2-A] is a rectangular division | segmentation electrode, [FIG. 2-B] is a honeycomb-shaped division | segmentation formed by the Y-shaped insulation slit. Electrode, [FIG. 2-C] is a view showing a metallized film provided with a honeycomb-shaped divided electrode formed by Mueller-Rear type insulating slits. It is a figure which shows 1st Embodiment of the metallized film which comprises the metallized film capacitor of this invention. It is a figure which shows the internal structure of the metallized film capacitor of this invention. It is a figure which shows the electric current path at the time of the dielectric breakdown in the division | segmentation electrode position of the metallized film which comprises the metallized film capacitor of this invention. It is a figure which shows the electric current path at the time of the dielectric breakdown in the division | segmentation electrode position of the metallized film which comprises the metallized film capacitor by a comparative example. It is a figure which shows 2nd Embodiment of the metallized film which comprises the metallized film capacitor of this invention. It is a figure which shows the deformation | transformation form of the metallized film which comprises the metallized film capacitor of this invention. It is a figure which shows the other deformation | transformation form of the metallized film which comprises the metallized film capacitor of this invention. It is a figure which shows an example of the laminated constitution of the conventional metallized film capacitor.

<First Embodiment>
FIG. 3 is a diagram showing a first embodiment of a metallized film constituting the metallized film capacitor of the present invention. In the metallized film, one end part (electrode formation region) in the width direction of the metallized film constitutes a metallicon connection part to which a metallicon for electrode extraction is connected, and an insulating margin (width direction of the metallized film in the other end part) A region 52) in which no vapor deposition electrode is formed is formed at one end portion. On the insulating margin 52 side of the metallized film, a plurality of T-shaped insulating slits 53 are arranged at regular intervals in the longitudinal direction. In addition, a plurality of insulating slits 55 are arranged at predetermined intervals in the longitudinal direction at the same pitch as the plurality of insulating slits 53 with a predetermined interval in the film width direction with respect to the plurality of insulating slits 53. A through-type insulating slit 54 is formed so as to penetrate the film in the width direction between some of the insulating slits 53 and 55 (so as to connect the insulating margin 52 and the metallicon connection portion). Insulating slits 54 are arranged in the longitudinal direction of the film with three 55 interposed therebetween. The slit width of the insulating slits 53, 54, and 55 is, for example, 0.2 mm. In each of the insulating slits 53, 54, and 55, the lengths of the slits extending in the film longitudinal direction (one insulating slit 53, three insulating slits 54, and two insulating slits 55) are the same.

  A plurality of divided electrodes 61 (corresponding to the “first divided electrode” of the present invention) in which the vapor deposition electrodes are divided are formed between the insulating slits 53 and between the insulating slits 53 and the insulating slits 54. The electrode 61 forms a first subdivided electrode portion. Further, it is divided into a plurality of divided electrodes 62 (corresponding to the “first divided electrode” of the present invention) in which the vapor deposition electrode is divided between the insulating slits 55 and between the insulating slit 55 and the insulating slit 54. The divided electrode 62 constitutes a second small divided electrode portion. Further, the vapor deposition electrode is divided into a plurality of divided electrodes 63 and 64 (corresponding to the “second divided electrode” of the present invention) by the plurality of insulating slits 54. Specifically, a first large divided electrode portion constituted by a plurality of divided electrodes 63 is formed between the first small divided electrode portion and the second small divided electrode portion in the film width direction, and is connected to the metallicon. A second large divided electrode portion composed of a plurality of divided electrodes 64 is formed on the portion side.

  These four divided electrode portions include a first small divided electrode portion, a first large divided electrode portion, a second small divided electrode portion, and a second small divided electrode portion from the insulating margin 12 side to the metallicon connection portion along the film width direction. Small divided electrode portions and large divided electrode portions are alternately arranged in the film width direction in the order of the large divided electrode portions. That is, in the film width direction, the small divided electrode portion is disposed adjacent to the large divided electrode portion. Each of the plurality of divided electrodes 61 is connected to the divided electrode 63 by a fuse 56 formed between the insulating slits 53 that sandwich the divided electrode 61 in the longitudinal direction and between the insulating slit 53 and the insulating slit 54. Each of the plurality of divided electrodes 62 is divided into divided electrodes 63 by fuses 57 and 58 formed between the insulating slits 55 sandwiching the divided electrodes 62 in the longitudinal direction and between the insulating slit 55 and the insulating slit 54, respectively. , 64.

  The intervals between the insulating slits arranged in the first subdivided electrode portion, that is, the intervals between the insulating slits 53 and between the insulating slit 53 and the insulating slit 54 are the intervals between the insulating slits 54 arranged in the first large divided electrode portion. The electrode area of the divided electrode 63 constituting the first large divided electrode part is smaller than that of the divided electrode 61 constituting the first small divided electrode part. The intervals between the insulating slits arranged in the second subdivided electrode portion, that is, the intervals between the insulating slits 55 and between the insulating slit 55 and the insulating slit 54 are the same as each other between the insulating slits 54 arranged in the first large divided electrode portion. And the electrode areas of the divided electrodes 63 and 64 constituting the first and second large divided electrode portions are smaller than the interval between the insulating slits 54 arranged in the second large divided electrode portion. It is larger than the electrode area of the divided electrodes 61 and 62 constituting the second small divided electrode portion.

  FIG. 4 is a diagram showing the internal structure of the metallized film capacitor of the present invention. Two metallized films formed as described above are overlapped and wound so that the metallicon connection part and the insulation margin face each other. The two metallized films are overlaid with the electrode forming surface on which the vapor deposition electrode is formed facing in the same direction. That is, the vapor deposition electrodes and the dielectric films are alternately arranged in the stacking direction so that the dielectric film is sandwiched between the vapor deposition electrodes. Then, after forming the wound metallized film into an oval shape, a metallicon for electrode drawing is formed at both ends (one end and the other end of the overlapped metallized film) to form a capacitor element 25. . Thereafter, a plurality of capacitor elements 25 are connected by the electrode plate 26 and the lead terminals 27 are connected. The connected capacitor element 25 is accommodated in a case 28, and a resin 29 is filled in the case 28 to obtain a metallized film capacitor.

  As described above, according to this embodiment, in the width direction of the metallized film, the small divided electrode portion composed of the plurality of divided electrodes (first divided electrodes) 61 and 62 has a plurality of divided electrodes (first electrodes). 2 divided electrodes) 63 and 64 are arranged adjacent to the large divided electrode portion. For this reason, at least one end of the first divided electrodes 61 and 62 is connected to the second divided electrodes 63 and 64 having a larger electrode area than the first divided electrodes 61 and 62 via a fuse. Even when dielectric breakdown occurs in the first divided electrodes 61 and 62, a current sufficient to operate the fuse flows from the second divided electrodes 63 and 64 adjacent to the first divided electrodes 61 and 62. The fuse can be reliably operated (the vapor deposition electrode of the fuse portion is scattered), and the divided electrodes that have caused the dielectric breakdown can be separated. Thereby, stable security can be obtained even if the divided electrodes are made smaller.

  Further, since the small divided electrode portions and the large divided electrode portions are alternately arranged in the width direction of the metallized film, the position of the insulating slit on the metallized film is prevented from being unevenly distributed in the width direction, and the metal It is possible to level the slidability of the plasticized film in the width direction. As a result, when the metallized film is wound, it is possible to suppress variation in the element winding state, and to ensure good voltage resistance at high temperatures.

  Further, the distance between the insulating slits arranged in the small divided electrode part (the distance between the insulating slit 53 and the insulating slit 54 and the distance between the insulating slit 54 and the insulating slit 55) is the distance between the insulating slits arranged in the large divided electrode part. The area of the first divisional electrodes 61 and 62 is divided into the second division while suppressing the film from becoming longer in the width direction by making it narrower than (the interval between the insulation slits 54 and the interval between the insulation slits 55). The area of the electrodes 63 and 64 can be reduced.

  Furthermore, when a metallized film capacitor is formed by a pair of metallized films formed by overlapping two metallized films, all of the large divided electrode portions formed on one of the pair of metallized films are paired with metallized. It is preferable to constitute so as to oppose the small divided electrode portion formed on the other side of the film. According to this configuration, for example, as shown in FIG. 5, the self-healing of the metallized film in the second divided electrode formed on one of the pair of metallized films (the metallized film located on the upper layer side in the figure). When dielectric breakdown exceeding the function (self-healing function) (dielectric material breaks at the position of the x mark) occurs (when vapor deposition electrodes conduct between a pair of metallized films through the broken dielectric part) However, the second electrode having a larger electrode area than the first divided electrode adjacent to the first divided electrode formed on the other of the pair of opposed metallized films (the metallized film located on the lower layer side in the drawing). Current flows from the divided electrodes into the divided electrodes. For this reason, the fuse formed between the first divided electrode and the second divided electrode formed on the other of the pair of metallized films is reliably operated (the vapor deposition electrode of the fuse portion is scattered), and the first The two split electrodes can be separated from the other split electrodes. Thereby, even when a dielectric breakdown occurs in the second divided electrode formed on one of the pair of metallized films, the insulation of the second divided electrode can be recovered and the function as a capacitor is maintained. be able to.

  Furthermore, when two metallized films are overlaid as described above, it is preferable to arrange a large-division electrode part on the metallicon connection part side of the metallized film for electrode drawing. This is because when a small divided electrode portion is arranged on the metallicon connection portion side (electrode lead side), dielectric breakdown occurs at the first divided electrode constituting the small divided electrode portion (a dielectric at the position of the x mark in the divided electrode). When the fuse connecting the first divided electrode and the second divided electrode is operated, the current path from the first divided electrode is completely cut off, and the capacitor does not function as a capacitor. There is. On the other hand, by arranging the large divided electrode portion on the metallicon connection portion side, the second divided electrode on the electrode lead-out side (the second divided electrode portion formed on one of the pair of metallized films) Even when dielectric breakdown occurs in the split electrode), the first metallization film (the other metallized film of the pair of metallized films, in FIG. 6, the metallized film disposed on the lower layer side) is formed. The fuse that connects the one divided electrode and the second divided electrode adjacent to the first divided electrode operates to leave an electrode region that functions as a capacitor.

  Examples of metallized film capacitors will be described below. In FIG. 3, the longitudinal dimension 61a, 62a of the first divided electrodes 61, 62 constituting the small divided electrode part is 5 mm, and the longitudinal dimension 63a of the second divided electrode 63, 64 constituting the large divided electrode part, 64a is 20 mm, the dimension in the film width direction is 23 mm for the first divided electrodes 61 and 62 and 26 mm for the second divided electrodes 63 and 64, and the first and second divided electrodes are connected. The dimensions of the fuses 56 to 58 were set to 0.2 mm. The dielectric was a 2.5 μm polypropylene film with a non-metallicon near-deposited electrode film resistance value of 10Ω / □ and a metallicon connection-deposited electrode film resistance value of 4Ω / □.

  Two metallized films formed as described above are wound so that the metallicon connection portion and the insulation margin face each other, and after forming into an oval shape, a metallicon is formed as an electrode lead at both ends to form a capacitor element. did. Further, as shown in FIG. 4, five capacitor elements 25 are connected by an electrode plate 26, lead terminals 27 are connected, housed in a case 28, filled with epoxy resin 29, cured, and 800 μF metallized film capacitor. Was made.

Second Embodiment
FIG. 7 is a view showing a second embodiment of the metallized film constituting the metallized film capacitor of the present invention. The second embodiment is greatly different from the first embodiment in that the vapor deposition electrode is divided by an insulating slit having a shape different from that of the first embodiment (FIG. 3), and the first divided electrode and the first divided electrode are divided. The second divided electrode having a larger electrode area is formed.

  In the metallized film according to the second embodiment, a plurality of Mueller-Rear shapes arranged in the longitudinal direction in the middle of the film width direction (inward arrow blades at both ends of a line segment having a predetermined length extending in the width direction) The first split electrodes 36A and 36B are respectively formed by the insulating slit 14 having a shape and a plurality of Y-shaped insulating slits 13 arranged in the longitudinal direction on the insulating margin 12 side. The Y-shaped insulating slit 13 and the Mueller-rear insulating slit 14 are arranged at the same pitch in the longitudinal direction, and some of the plurality of Y-shaped insulating slits 13 and the plurality of Mueller-rear insulating slits 14 (1 The above is extended and coupled in the width direction of the metallized film, and constitutes a through-type insulating slit 35 (in FIG. 7, Y-shaped insulation located at the second position from the right and the second position from the left). The slit 13 and the Müller-Rear insulating slit 14 are connected to extend in the width direction of the metallized film).

  By forming the insulating slits as described above, the first small divided electrode portion composed of a plurality of divided electrodes (corresponding to the first divided electrode of the present invention) 36A and the plurality of divided electrodes (the present invention). A plurality of divided electrodes having a larger electrode area than the divided electrodes 36A and 36B (corresponding to the “second divided electrode” of the present invention). The first large divided electrode portion composed of 37A is formed. In addition, the first subdivided electrode portion includes a plurality of segmented electrodes (corresponding to the “second segmented electrode” of the present invention) 37B having a larger electrode area than the segmented electrode 36B on the metallicon connection portion side. A second large divided electrode portion is formed. The fuse 18 is connected between the divided electrode 36A and the divided electrode 37A, between the divided electrode 37A and the divided electrode 36B, and between the divided electrode 36B and the divided electrode 37B.

  Also in this embodiment, the first subdivided electrode portion, the first large subdivided electrode portion, the second subdivided electrode portion, and the second large subdivided electrode from the insulating margin 12 side to the metallicon connection portion along the film width direction. The small divided electrode portions and the large divided electrode portions are alternately arranged in the film width direction in the order of the portions. That is, in the film width direction, the small divided electrode portion is disposed adjacent to the large divided electrode portion. Therefore, the same effect as that of the first embodiment can be obtained by the second embodiment.

  Examples of metallized film capacitors will be described below. The pitch of the insulating slits 13 and 14 for dividing the metallized film dividing electrodes (first dividing electrodes) 36A and 36B shown in FIG. 7 in the longitudinal direction of the film is 12.0 mm, and the area of the dividing electrode 36A is the dividing electrode 36B. It was half of. The width of the fuse 18 connecting each divided electrode was set to 0.2 mm. The dielectric was a 2.5 [mu] m polypropylene film, the non-metallicon near-deposited electrode film resistance value was 10 [Omega] / square, and the metallicon connection part vapor deposition electrode film resistance value was 4 [Omega] / square. Then, in the same manner as in the first embodiment, two metallized films formed in this way are wound so that the metallicon connection part and the insulation margin face each other, and are formed into an oval shape, and then the electrodes are drawn out at both ends. Metallicons were formed as capacitor elements.

  Next, characteristic examples of the metallized film capacitor according to the first and second embodiments of the present invention (hereinafter referred to as “Example 1” and “Example 2”, respectively) will be described in comparison with comparative examples. The divided electrode dimensions (or the pitch of the insulating slit), the fuse width, and the deposited electrode film resistance value of the metallized film capacitor according to the first and second embodiments of the present invention are as described above.

<Comparative example>
Next, a comparative example of a metalized film capacitor will be described. The pitch of the insulating slit 5 that divides the metallized film dividing electrode 7 shown in FIG. 2 ([FIG. 2-A]) in the film longitudinal direction is 10.0 mm, and the pitch of the insulating slit 6 that is divided in the film width direction is 18 mm. The width of the fuses 8 and 11 connecting the divided electrodes 7 was 0.2 mm. The dielectric was a 2.5 μm polypropylene film, the non-metallicon vicinity deposited electrode film resistance was 10Ω / □, and the metallicon connection film resistance was 4Ω / □.

  Two of the divided electrode metallized films were overlapped and wound so that the metallicon connection portion and the insulation margin were opposed to each other, formed into an oval shape, and then formed into a metallicon at both ends to form a capacitor element. Further, as shown in FIG. 4, five capacitor elements 25 are connected by an electrode plate 26 and connected to a lead terminal 27, housed in a case 28, filled and cured with an epoxy resin 29, and an 800 μF metallized film. A capacitor was made.

  Samples were prepared for Examples 1 and 2 and Comparative Example, and a durability test (temperature 110 ° C., 750 VDC, applied for 1000 hours) was performed. After the test, the capacitance change rate of the sample was measured. The test results are shown in Table 1.

  From the test results shown in Table 1, in Examples 1 and 2, no short circuit occurred at the end of the test, whereas in the comparative example, a short circuit occurred during the test. This is because when the dielectric film of the metallized film according to Examples 1 and 2 causes dielectric breakdown in the dielectric polypropylene film, the current sufficient to scatter and separate the fuse is the second divided electrode (the divided electrode having a relatively large electrode area). ) Flows into the first divided electrode (divided electrode having a relatively small electrode area). As a result, it is possible to separate the divided electrodes that have caused dielectric breakdown, and avoid the occurrence of a short circuit. On the other hand, when a dielectric breakdown occurs in the metallized film according to the comparative example, it is considered that the current connected to the divided electrodes does not flow enough to scatter and separate the fuses, resulting in a short mode. . As described above, according to the metallized film capacitor of the present invention, it is easy to separate the divided electrodes that have caused dielectric breakdown, and stable security can be obtained.

<Others>
The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the first embodiment (FIG. 3), the film width direction of the small divided electrode portion (first and second small divided electrode portions) and the large divided electrode portion (first and second large divided electrode portions). Of the divided electrodes (first divided electrodes) constituting the first and second subdivided electrode portions with the same length of the slits and the same pitch of the insulating slits 53 and the same pitch of the insulating slits 55. Although the length in the longitudinal direction and the length in the longitudinal direction of the film of the divided electrodes (second divided electrodes) constituting the first and second large divided electrode portions are the same, it is not limited thereto. For example, a metallized film may be configured as shown in FIG.

  FIG. 8 is a view showing a modified form of the metallized film constituting the metallized film capacitor of the present invention. As shown in the drawing, the lengths in the film width direction of the small divided electrode portions (first and second small divided electrode portions) and the large divided electrode portions (first and second large divided electrode portions) are different from each other. A metallized film may be configured as described above. Further, as shown in the figure, the length of the divided electrodes (first divided electrodes) constituting the first and second small divided electrode portions in the film longitudinal direction, and the first and second large divided electrodes, respectively. You may comprise a metallized film so that the length of the film longitudinal direction of the division electrode (2nd division electrode) which each comprises a part may differ from each other.

  Moreover, in the said embodiment, although the electrode area of each of the some 1st division | segmentation electrode arranged in the film longitudinal direction is made the same, you may make it different. Similarly, although the electrode areas of the second divided electrodes arranged in the film longitudinal direction are the same, they may be different. The point is that the electrode area of the second divided electrode constituting the large divided electrode portion adjacent to the first divided electrode constituting the small divided electrode portion is larger than that of the first divided electrode.

  In addition, when two metallized films are overlapped, the metallized films having the same electrode pattern may be overlapped, or the metallized films having different electrode patterns may be overlapped. Even in this case, the metallized film can be overlaid so that all of the large divided electrode parts formed on one of the pair of metallized films are opposed to the small divided electrode part formed on the other of the pair of metallized films. preferable. Thereby, even when a dielectric breakdown occurs in the second divided electrode formed on one of the pair of metallized films, the insulation of the second divided electrode can be recovered and the function as a capacitor is maintained. be able to.

  Moreover, in the said embodiment, the width | variety of the divided electrode part (small divided electrode part and large divided electrode part) by which the vapor deposition electrode was divided | segmented into the some divided electrode by the insulation slit arranged at intervals in the longitudinal direction of the metallized film. Although four rows are arranged along the direction, the number of the divided electrode portions is not limited to this, and may be three rows or five rows or more.

  FIG. 9 is a view showing another modification of the metallized film constituting the metalized film capacitor of the present invention. In FIG. 9, the divided electrode portions are arranged in three rows along the width direction. Specifically, a small divided electrode portion composed of a plurality of divided electrodes (first divided electrodes) 39 is arranged at the center in the film width direction, and a plurality of divided electrodes (first electrodes) having a larger electrode area than the divided electrodes 39 are arranged. 2 divided electrodes) 40 are disposed adjacent to both sides in the width direction of the small divided electrode portion. The first divided electrodes 39 adjacent to each other with the insulating slits 35c arranged in the small divided electrode portions sandwiched in the longitudinal direction are connected by a fuse 18b.

  Here, the width A of the fuse that connects the first divided electrode 39 that forms the small divided electrode portion and the second divided electrode 40 that forms the large divided electrode portion is connected to the first divided electrodes 39. It may be larger than the width B of the fuse 18b. According to such a configuration, a current flows through the fuse 18b, and the current path in the center portion of the capacitor element can be further increased to suppress self-heating. In addition, by making the width of the fuse 18 larger than the width of the fuse 18b, sufficient operability of the fuse is ensured even in the divided electrode on the center side of the film having a small divided electrode area and low energy for operating the fuse. be able to.

DESCRIPTION OF SYMBOLS 1 ... Polypropylene film 2 ... Metallicon vicinity vapor deposition electrode 3 ... Non-metallicon vicinity vapor deposition electrode 4 ... Insulation margin 5 ... Width direction insulation slit 6 ... Longitudinal direction insulation slit 7, 7a, 7b ... Split electrode 8, 8a, 8b ... Fuse 9 Longitudinal insulating slit 10 near the metallicon ... Metallicon connection 11 ... Fuses 12, 12a, 12b near the metallicon ... Insulation margins 13, 13a ... Y-shaped insulating slits 14, 14a ... Mueller-Rear insulating slits 18, 18b ... Fuses 25 ... Capacitors Element 26 ... Electrode plate 27 ... Lead terminal 28 ... Case 29 ... Epoxy resins 35, 35a, 35c ... Insulating slits 36A, 36B, 39 ... First divided electrodes 37A, 37B, 40 ... Second divided electrodes 39a ... First Dimension 40a in the longitudinal direction of the divided electrode of the second divided electrode. Lum longitudinal dimension 52 ... insulation margins 53, 54, 55 ... insulation slits 56, 57, 58 ... fuses 61, 62 ... first divided electrodes 63, 64 ... second divided electrodes 61a ... (first small divided electrodes) The film longitudinal direction dimension 62a of the split electrode (which constitutes a part) The film longitudinal direction dimension 63a of the split electrode (which constitutes the second small split electrode part) The part length of the split electrode (which constitutes the first large split electrode part) Film longitudinal dimension 64a ... (constituting the second large divided electrode part) Film longitudinal dimension of the divided electrode

Claims (3)

In a metallized film capacitor in which a metallized film provided with an evaporation electrode on at least one surface of a dielectric film is wound or laminated to form a capacitor element, and metallicons for electrode drawing are connected to both end surfaces of the capacitor element.
A subdivided electrode portion that forms a plurality of first divided electrodes along the longitudinal direction in which the vapor deposition electrode is divided by insulating slits arranged at intervals in the longitudinal direction of the metallized film;
A plurality of second divisional electrodes having a larger electrode area than the first divisional electrodes are divided along the longitudinal direction by dividing the vapor deposition electrodes by insulating slits arranged at intervals in the longitudinal direction of the metallized film. A large divided electrode portion to be formed,
In the width direction of the metallized film, the small divided electrode portions and the large divided electrode portions are arranged alternately adjacent to each other,
Each of the plurality of first divided electrodes is connected to the second divided electrode by a fuse formed between insulating slits sandwiching the first divided electrode in the longitudinal direction. Film capacitor.   The metallized film capacitor according to claim 1, wherein an interval between the insulating slits arranged in the small divided electrode portion is narrower than an interval between the insulating slits arranged in the large divided electrode portion. 2. The metallized film capacitor according to claim 1, wherein the large-divided electrode portion is disposed on the metallicon connection portion side of the metallized film.

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