JP4337476B2 - Multilayer film capacitor - Google Patents

Description

  The present invention relates to a laminated film capacitor.

  As shown in FIG. 4, in the conventional multilayer film capacitor, first, a base capacitor is formed, and this base capacitor is cut into a predetermined size to form a capacitor element 50. In this case, the capacitor element 50 is obtained by alternately laminating dielectrics 51 and vapor-deposited metals 52. In this capacitor element 50, metallicon metal 55 is sprayed on the end face 54 different from the cut surface 53 to form metallicon electrodes 55 and 55 (see FIG. 6). The capacitor element 50 is a laminated body in which the dielectrics 51 and the deposited metal 52 are alternately laminated as described above. When the capacitor element 50 is formed, a pair of end faces on which the metallicon metal is sprayed in the base capacitor. 54 and 54 are not cut surfaces.

  Further, a margin portion 56 is formed on the end side of the vapor deposited metal 52, and as shown in FIG. 6, when a plurality of dielectrics 51 and vapor deposited metals 52 are alternately laminated, In the dielectrics 51 and 51 corresponding to the upper and lower sides, there is a shift on the metallicon electrodes 55 and 55 side.

  By the way, when the base capacitor is cut, as shown in FIG. 5, cutting waste 57 (cutting waste made of dielectric 51 and vapor deposition metal 52) may adhere to cut surface 53. At this time, vapor-deposited metals (vapor-deposited electrodes) 52 and 52 of different electrodes are on the same plane at the cut surface 53. In such a surface, if the cutting waste 57 exists, the withstand voltage of the capacitor is lowered and the quality is deteriorated. Further, as shown in FIG. 6, the edge portions 58 of the metallicon electrodes 55, 55 formed by spraying the metallicon metal are exposed to the outside. Of these edge portions 58, the edge portion 58a close to the end of the vapor deposition electrode 52 is particularly inferior in strength, and the edge portion 58a may be lost due to external impact or the like. As described above, when the edge portion 58a or the like is chipped, electric discharge is likely to occur, leading to a reduction in the withstand voltage of the capacitor. In addition, the connection deterioration of the metallicon electrode 55 is likely to occur, and stress due to external vibration or the like is concentrated on the margin portion 56 having a low hardness, which may cause the connection between the metallicon electrode 55 and the vapor deposition electrode 52 to be disconnected. There is also.

  The present invention has been made to solve the above-described conventional drawbacks, and an object of the present invention is to provide a multilayer film capacitor capable of stabilizing the quality without causing a decrease in withstand voltage.

  Accordingly, the laminated film capacitor according to claim 1 forms a capacitor element 3 by alternately laminating a plurality of metal vapor-deposited electrodes 1 and dielectrics 2, and a pair of metallicon-compatible end faces 4 opposite to each other of the capacitor element 3. 4 is a multilayer film capacitor in which metallicon electrodes 5 and 5 are formed, and a dielectric element adjacent to the metallicon non-corresponding end faces 8 and 8 of the capacitor element 3 different from the metallicon-corresponding end faces 4 and 4 along the laminating direction. The bodies 2 and 2 are laminated so as to be displaced in a direction perpendicular to the lamination direction.

  In the multilayer film capacitor according to claim 1, the dielectrics 2, 2 adjacent to each other in the stacking direction on the non-metallicon-compatible end surfaces 8, 8 side of the capacitor element 3 different from the metallicon-compatible end surfaces 4, 4 are stacked in the stacking direction. Since the layers are laminated so as to be shifted in the orthogonal direction, the vapor deposition electrodes are not arranged on the same surface on the metallicon non-corresponding end surfaces 8 and 8 side different from the metallicon electrodes 5 and 5 side.

  The multilayer film capacitor according to claim 2 is characterized in that a coating of an insulating material is applied to the end surfaces 8 and 8 of the capacitor element 3 that do not correspond to the metallicon.

  In the multilayer film capacitor according to the second aspect, since the insulating material coating is applied to the end faces 8, 8 of the capacitor element 3 that do not correspond to the metallicon, the end faces 8, 8 that do not support the metallicon are protected by the insulating material. be able to.

  The laminated film capacitor of claim 3 forms a capacitor element 3 by alternately laminating a plurality of metal vapor-deposited electrodes 1 and dielectrics 2, and a pair of metallicon-compatible end faces 4, 4 opposite to each other of the capacitor element 3. The multilayer film capacitor is formed by forming metallicon electrodes 5 and 5 and covering end surfaces 11 and 11 of the capacitor element 3 in the stacking direction with protective members 15 and 15, between the metallicon electrodes 5 and 5 facing each other. The width dimension of the protective member 15 in the connecting direction is larger than the element width of the capacitor function portion.

  In the laminated film capacitor according to the third aspect, the width dimension of the protective member 15 in the direction connecting the facing metallicon electrodes 5 and 5 is made larger than the element width of the capacitor function portion. The edge portions 16 can be protected by the protective member 15.

  According to the multilayer film capacitor of claim 1, since the vapor deposition electrode is not arranged on the same surface on the end face side not corresponding to the metallicon, impurities such as cutting waste generated at the time of forming the capacitor element adhere to the end face not corresponding to the metallicon. Even if it does, it does not cause the fall of the withstand voltage of a capacitor by adhesion of an impurity. That is, withstand voltage against impurities such as cutting waste can be increased, and quality can be stabilized.

  According to the multilayer film capacitor of the second aspect, since the coating of the insulating material is applied to the end surface not corresponding to the metallicon, the end surface corresponding to the non-metallicon can be protected by the insulating material. For this reason, it is possible to reliably prevent impurities other than cutting scraps from adhering to the end face not corresponding to the metallicon, to improve the withstand voltage, and to provide a higher quality capacitor.

  According to the laminated film capacitor of the third aspect, the edge portion of the metallicon electrode can be protected by the protective member. As a result, it is possible to prevent chipping of the edge portion of the metallicon electrode due to external impact or the like, and to avoid lowering the withstand voltage of the capacitor. In addition, it is possible to prevent the deterioration of the connection of the metallicon electrode, and to mitigate the influence on the weak point portion (margin portion) inside the element with respect to external vibration or the like.

  Next, specific embodiments of the multilayer film capacitor of the present invention will be described in detail with reference to the drawings. FIG. 1 is a simplified sectional view of this multilayer film capacitor. This multilayer film capacitor includes a capacitor element 3 in which a plurality of metal vapor-deposited electrodes 1 and dielectrics 2 are alternately stacked, and is shown in FIG. As described above, the metallicon electrodes 5 and 5 are formed on a pair of opposing end surfaces (end surfaces corresponding to the metallicon) 4 and 4 of the capacitor element 3. In this case, a film body 6 is constituted by a dielectric (dielectric film) 2 and a metal vapor-deposited electrode 1 formed on one surface (upper surface) of the dielectric film 2, and the plurality of film bodies 6 are overlapped. Match.

  As shown in FIG. 2, the film body 6 is formed with the metal vapor-deposited electrode 1, leaving a non-vapor-deposited portion (margin portion) 7 at the end on the metallicon-compatible end face 4, 4 side where the metallicon electrode 5 is formed. The non-deposited portion (margin portion) 7 of the film body 6 is disposed at a conflicting position (a position opposite to 180 degrees). When laminating the film body 6, the upper and lower film bodies 6, 6 are arranged on the metallicon-compatible end face 4 side corresponding to the metallicon electrode 5 and on the end face (metallicon-incompatible end face) 8 side different from the metallicon electrode 5. These are shifted by predetermined shift widths W1 and W2, respectively.

  After the plurality of film bodies are superposed, the metallicon metal 5 is sprayed on the metallicon-compatible end faces 4 and 4 on the metallicon electrode 5 and 5 side, as shown in FIG. 5 are formed. Also, on the end face 8 that does not correspond to the metallicon electrode 5, as shown by the phantom line in FIG. 1B, an insulating material (for example, epoxy resin) is coated to form the coating parts 10 and 10. To do.

  In the multilayer film capacitor, since the upper and lower vapor deposition electrodes 1 and 1 are not arranged on the same surface on the end surface 8 not corresponding to the metallicon, impurities such as cutting waste generated when the capacitor element 3 is formed are not supported on the end surface corresponding to the metallicon. Even if it adheres to the 8 side, the withstand voltage of this capacitor does not decrease. That is, the withstand voltage can be increased against impurities such as cutting waste, and the quality can be stabilized. In particular, as shown in FIG. 1 (b), if the end surface 8 side that does not correspond to the metallicon is coated with an insulating material and the end surface 8 side that does not correspond to the metallicon is protected by the coating portion 10, it is not compatible with the metallicon. Impurities can be reliably prevented from adhering to the end face 8, and the voltage resistance is improved. For this reason, even if the coating part 10 is not provided, it is possible to prevent a decrease in withstand voltage due to impurities of cutting waste generated at the time of manufacture. Can be prevented. For this reason, what provided the coating part 10 can provide a higher quality capacitor.

  Next, FIG. 3 shows another embodiment, in which case the end surface 11 in the stacking direction of the capacitor element 3, that is, the lower surface 13 covering the upper surface 12 is covered with protective members 15 and 15. The protective member 15 is made of a film body such as PP (polypropylene), PET (polyethylene terephthalate), or PPS (polyphenylene sulfide). The width A of the protective member 15 is made larger (wider) than the element width B of the capacitor function portion. Here, the width dimension A of the protective member 15 is the dimension of the protective member 15 in the direction connecting the metallicon electrodes 5 and 5 facing each other. In this case, the width dimension A is set to be substantially the same as the dimension between the outer ends of the metallicon electrodes 5 and 5. The dimension in the direction perpendicular to the direction of the width dimension A is such that it covers the coating portion 10. The protective member 15 ensures a thickness of at least 10 μm. That is, the thickness of the protective member 15 is 10 μm or more.

  For this reason, this protective member 15 can cover and protect the edge portions 16 of the metallicon electrodes 5 and 5 from the outside. Since the other structure of the multilayer film capacitor shown in FIG. 3 is the same as that of the multilayer film capacitor shown in FIG. 1, the same reference numerals are assigned to the same members and the description thereof is omitted. In the laminated film capacitor shown in FIG. 3, the metal spraying for forming the metallicon electrodes 5 and 5 is performed after the protective member 15 covers the end face 11 in the lamination direction. Also in the laminated film capacitor shown in FIG. 3, the coating portion 10 may or may not be provided.

  By the way, if the protective member 15 is not provided, the edge portions 16... Of the metallicon electrodes 5 and 5 are exposed to the outside and may be lost due to external impact or the like. The edge portion 16a adjacent to the end of the metallicon electrode 5 is particularly weak in strength and may be easily chipped. However, in the laminated film capacitor shown in FIG. 3, each edge portion 16... Can be protected by this protective member 15, and the edge portion 16a and the like are prevented from being chipped. As a result, the withstand voltage of the capacitor is not lowered, and the deterioration of the connection of the metallicon electrode 5 can be prevented, and the influence on the weak point portion (margin portion 7) inside the element with respect to vibration from the outside can be mitigated. Even in the case of the laminated film capacitor shown in FIG. 3, the adjacent dielectrics 2 and 2 along the laminating direction are laminated on the non-metallicon-compatible end faces 8 and 8 side so as to be shifted in the direction perpendicular to the laminating direction. Although it is preferable, it may not be shifted in this way.

  Moreover, in each said embodiment, although the film body 6 forms the metal vapor deposition electrode 1 on the single side | surface of the dielectric film 2, as the film body 6, the metal vapor deposition electrode 1 on both surfaces of the dielectric film 2, 1 may be formed. That is, in the case where the metal vapor-deposited electrode 1 is formed on one surface of the dielectric film 2, a laminated film capacitor having the metal vapor-deposited electrodes 1 and 1 facing each other with the dielectric 2 interposed therebetween is obtained by superimposing the film body 6. Can be configured. Further, in the case where the metal vapor-deposited electrodes 1 and 1 are formed on both surfaces of the dielectric film 2, the metal vapor deposition facing each other with the dielectric 2 sandwiched by interposing another dielectric film between the film bodies 6 and 6. A laminated film capacitor having electrodes 1 and 1 can be formed.

  Although specific embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the present invention. For example, the number of film bodies 6 (consisting of the dielectric film 2 and the metal vapor-deposited electrode 1) to be overlaid can be arbitrarily increased or decreased. The dielectric film 2 may be made of a dielectric material generally used for this type of laminated film capacitor, such as polypropylene (PP), polyethylene terephthalate (PET), polyphenylene sulfide (PPS), or the like. The metal deposition electrode 1 can also be composed of a metal generally used for this type of laminated film capacitor, for example, aluminum (Al), zinc (Zn), a mixed metal thereof, or the like. Furthermore, as the sprayed metal (metallicon metal), a metal containing zinc (Zn), tin (Sn), or the like can be used. In addition, various electrically insulating materials can be used as the material of the coating portion 10, and various resins having excellent insulation properties and strength can be used as the protective member 15. By the way, the thickness of the protective member 15 is set to 10 μm or more. However, if the thickness is too large, the capacitor is undesirably increased in size, and varies depending on the size of the capacitor element 3 and the like, but is preferably slightly over 10 μm.

An embodiment of the multilayer film capacitor of the present invention is shown, wherein (a) is a simplified cross-sectional view in which a metallicon electrode appears, and (b) is a simplified cross-sectional view in which a coating portion of an insulating material appears. It is a disassembled perspective view of the capacitor | condenser element of the said multilayer film capacitor. It is a principal part simplified perspective view which shows other embodiment of the laminated film capacitor of this invention. It is a simplified perspective view of the capacitor element of the conventional multilayer film capacitor. It is sectional drawing explaining the problem of the conventional multilayer film capacitor. It is a simplified sectional view of a conventional multilayer film capacitor.

Explanation of symbols

  1 .... Metal vapor deposition electrode 2 .... Dielectric material 3 .... Capacitor element 4 .... Metallicone compatible end face 5 .... Metalconic electrode 8, ... Metallicon non-compatible end face 11 .... Lamination direction end face 15 ... Protective member

Claims (3)

  A plurality of metal vapor deposition electrodes (1) and dielectrics (2) are alternately laminated to form a capacitor element (3), and a pair of metallicon-compatible end faces (4) (4) facing each other of the capacitor element (3). ) Formed of metallicon electrodes (5) and (5), which are different from the metallicon-compatible end faces (4) and (4) of the capacitor element (3), which are not metallicon-compatible end faces (8) and (8). On the side, the laminated film capacitor is characterized in that the dielectrics (2) and (2) adjacent along the laminating direction are laminated so as to be displaced in a direction perpendicular to the laminating direction.   The laminated film capacitor according to claim 1, wherein a coating of an insulating material is applied to the end face (8) (8) of the capacitor element (3) that does not correspond to metallicon.   A plurality of metal vapor deposition electrodes (1) and dielectrics (2) are alternately laminated to form a capacitor element (3), and a pair of metallicon-compatible end faces (4) (4) facing each other of the capacitor element (3). ) Formed of metallicon electrodes (5) and (5), and the end faces (11) and (11) in the stacking direction of the capacitor element (3) are covered with protective members (15) and (15). On the side of the end surfaces (8) and (8) of the capacitor element (3) that are different from the end surfaces (4) and (4) corresponding to the metallicons, the dielectrics (2) and (2) that are adjacent along the stacking direction The protective member (15) has a width dimension larger than the element width of the capacitor function portion in the direction connecting the metallicon electrodes (5) and (5) facing each other. That Multilayered film capacitor and butterflies.