JP5020107B2 - Solid electrolytic capacitor - Google Patents

Description

  The present invention relates to a bottom electrode type solid electrolytic capacitor suitable for surface mounting on a printed wiring board or the like.

  A bottom electrode type solid electrolytic capacitor suitable for surface mounting on a printed wiring board or the like has a structure as shown in FIG. FIG. 7A is a perspective view of the solid electrolytic capacitor, and FIG. 7B is a cross-sectional view taken along line C-C ′ of the configuration shown in FIG.

  As shown in FIG. 6, this solid electrolytic capacitor has a dielectric film in which the surface of an anode body 1 made of a sintered body of a valve action metal (tantalum, niobium, titanium, aluminum, etc.) is oxidized. Layer 2, a conductive inorganic material such as manganese dioxide, or a solid electrolyte layer 3a made of a conductive organic material such as a TCNQ complex salt or a conductive polymer, and a cathode lead layer 3b made of conductive carbon, silver, etc. The capacitor layer 10 and the cathode lead layer are collectively formed as a cathode layer 3 to form the capacitor element 10.

As shown in FIG. 7, the insulating tape 14 is applied to the upper surface 63 of the conventional anode terminal 60, the conductive adhesive 11 is applied to the conventional cathode terminal 70, and then the capacitor element 10 is connected to the conventional anode terminal 60 and the conventional anode terminal 60. The conventional pillow member 50 is placed on the conventional cathode terminal 70 and connected to the anode lead member 4 drawn from the anode body 1, and the conventional anode terminal 60 is connected to the conventional pillow member 50. The conventional cathode terminal 70 is connected to the cathode lead layer 3b through the conductive adhesive 11, and the capacitor element 10 is covered with the exterior resin 8 made of epoxy resin or the like,
The anode terminal and the cathode terminal have a conventional anode terminal lower surface 64 and a conventional cathode terminal lower surface 74 that are respectively exposed from the exterior resin on the bottom surface of the solid electrolytic capacitor (for example, Patent Document 1).
Japanese Patent Laid-Open No. 2001-6978 (FIG. 1)

  In the solid electrolytic capacitor according to the conventional example, the anode body 1 is placed on both the conventional anode terminal 60 and the conventional cathode terminal 70. Therefore, it is necessary to affix the insulating tape 13 in order to insulate the conventional anode terminal 60 and the cathode lead layer 3b covering the surface of the capacitor element 10. This is because the manufacturing method becomes complicated due to an increase in the number of steps in manufacturing the solid electrolytic capacitor, and the cost increases.

A solid electrolytic capacitor according to the present invention includes a capacitor element in which a dielectric film layer and a cathode layer are sequentially formed on a surface of an anode body on which an anode lead member is projected, and an anode in which the anode lead member is connected via a pillow member. A solid electrolytic capacitor comprising a terminal, a cathode terminal to which the cathode layer is connected, and an exterior resin that covers the capacitor element,
The pillow member has a flat surface,
The upper surface of the pillow member is connected to the anode lead member, the lower surface of the pillow member is connected to the anode terminal,
The upper surface of the pillow member is formed obliquely upward with respect to the upper surface of the anode terminal in the direction in which the anode lead-out member protrudes.
The capacitor element is directed in a direction in which the cathode terminal lower end portion of the capacitor element lower surface is in contact with the cathode terminal upper surface and the anode lead-out member protrudes with respect to the arrangement direction of the anode terminal and the cathode terminal. It is characterized by being arranged diagonally upward.

More preferably, the upper surface of the pillow member and the lower surface of the pillow member are substantially parallel to each other,
Regarding the arrangement direction of the anode terminal and the cathode terminal, the end closer to the anode terminal of the lower surface of the pillow member is separated from the upper surface of the anode terminal,
The end near the cathode terminal on the lower surface of the pillow member is connected to the upper surface of the anode terminal.

  More preferably, the projected portion projected from the end closer to the anode terminal on the lower surface of the capacitor element in the vertical direction from the upper surface of the solid electrolytic capacitor toward the anode terminal overlaps the upper surface of the anode terminal.

  More preferably, the pillow member and the anode terminal are connected by laser welding.

  According to the configuration of the present invention, the pillow member upper surface 51 is formed obliquely upward, and the end of the capacitor element lower surface 101 near the anode terminal 6 and the anode terminal upper surface 61 are disposed obliquely. The distance between the cathode layer 3 on the lower surface 101 of the element and the upper surface 61 of the anode terminal is increased, and no short circuit occurs.

  In addition, even if the projected portion of the capacitor element lower surface 101 overlaps the anode terminal upper surface 61, a short circuit does not occur.

  As a result, the insulating tape 13 for preventing a short circuit becomes unnecessary, the cost of the insulating tape 13 and the process for sticking are eliminated, and the manufacturing method is simplified.

  Moreover, since the pillow member lower surface 52 and the pillow member upper surface 51 face each other substantially in parallel, the pillow member 5 can be easily formed.

  Further, by laser welding one of the lower surfaces of the pillow member 5 to the anode terminal 6, the pillow member lower surface 52 and the anode terminal upper surface 61 can be easily disposed obliquely by being pulled to the welded side of the pillow member lower surface 52. .

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[Example 1]
The configuration of the solid electrolytic capacitor according to the first embodiment of the present invention is shown in FIG. 1A is a perspective view of the solid electrolytic capacitor, FIG. 1B is a bottom view of the solid electrolytic capacitor, and FIG. 1C is a cross-sectional view taken along the line AA ′ of the configuration shown in FIG. It is.

  This solid electrolytic capacitor is shown in detail in FIG. On the surface of the anode body 1 made of a sintered body of a valve action metal (tantalum, niobium, titanium, aluminum, etc.), a dielectric coating layer 2 obtained by oxidizing the anode body surface, a conductive inorganic material such as manganese dioxide, or Solid electrolyte layer 3a made of a conductive organic material such as TCNQ complex salt, conductive polymer, and cathode lead layer 3b made of conductive carbon, silver, etc. (where the solid electrolyte layer and the cathode lead layer are combined with the cathode layer 3) The capacitor element 10 is formed by sequentially forming the capacitor element 10.

  Next, as shown in FIG. 1, the pillow member 5 has the pillow member upper surface 51 connected to the anode lead-out member 4 as an anode terminal upper surface 61 connected to the pillow member lower surface 52 of the anode terminal 6. On the other hand, the anode lead member 4 is formed obliquely upward in the projecting direction. Further, the pillow member lower surface 52 is connected to the anode terminal upper surface 61.

Next, the conductive adhesive 11 was applied to the upper surface 71 of the cathode terminal, the end near the cathode terminal of the lower surface 101 of the capacitor element was in contact with the upper surface of the cathode terminal, and the anode lead-out member 4 was projected. Placed diagonally upwards in the direction,
The pillow member 5 is connected to the anode lead member 4 drawn out from the anode body 1, the capacitor element lower surface 101 is connected to the cathode terminal upper surface 71, and then the capacitor element 10 is attached to the exterior resin 8 made of epoxy resin or the like. And coated.

  The anode terminal 6 and the cathode terminal 7 have an anode lower surface 62 and a cathode lower surface 72 respectively exposed from the exterior resin 8 on the lower surface of the solid electrolytic capacitor.

  Here, when the anode body 1 is made of a sintered body of tantalum powder, the anode lead member 4 is preferably a tantalum wire.

  As shown in FIG. 1, the distance between the capacitor element bottom surface 101 and the anode terminal top surface 61 is increased, and short-circuiting does not occur.

[Example 2]
FIG. 2 shows a cross-sectional view of the configuration of the solid electrolytic capacitor according to the second embodiment of the present invention.

  The method for producing a solid electrolytic capacitor is such that the pillow member upper surface 51 and the pillow member lower surface 52 face each other substantially in parallel, and the anode terminal of the pillow member lower surface 52 is in the arrangement direction of the anode terminal 6 and the cathode terminal 7. It was produced in the same manner as in Example 1 except that the side edge portion was separated from the anode terminal upper surface 61 and the cathode terminal side edge portion of the pillow member lower surface 52 was connected to the anode terminal upper surface 61.

  In this case, since the pillow member upper surface 51 and the pillow member lower surface 52 face each other substantially in parallel, the pillow member 5 can be easily manufactured.

  Here, when connecting the end closer to the cathode terminal of the lower surface 52 of the pillow member and the upper surface 61 of the anode terminal, it is more preferable to connect by laser welding. This is because, in the case of resistance welding, it is necessary to press the electrode of the welding equipment against the welded object, and as shown in FIG. Although it is difficult to be inclined, one of the pillow member lower surfaces 52 is laser welded to the anode terminal upper surface 61 so that the pillow member lower surface 52 and the anode terminal upper surface 61 are easily pulled. Can be placed diagonally.

[Example 3]
FIG. 3 shows a cross-sectional view of the configuration of the solid electrolytic capacitor according to the third embodiment of the present invention.

  The solid electrolytic capacitor was manufactured in the same manner as in Example 2 except that the capacitor element 10 was enlarged. In this case, even when the capacitor element 10 is enlarged and the projected portion of the capacitor element lower surface 101 near the anode terminal overlaps the anode terminal upper surface 61, the capacitor element 10 is disposed obliquely. The capacitor element lower surface 101 and the anode terminal upper surface 61 are not in contact with each other.

  Therefore, unlike the conventional example shown in FIG. 7, it is not necessary to apply the insulating tape 13 to the upper surface 63 of the anode terminal, and the cost is reduced and the manufacturing method is facilitated.

[Example 4]
FIG. 4 shows a cross-sectional view of the configuration of the solid electrolytic capacitor according to the fourth embodiment of the present invention.

  The capacitor was manufactured in the same manner as in Example 3 except that the notch 12 of the anode terminal 6 was provided. As a result, the size of the capacitor element 10 is not changed, and the gap between the end closer to the cathode terminal of the upper surface 61 of the anode terminal and the capacitor element 10 becomes larger, and the short circuit is less likely to occur.

[Example 5]
FIG. 5 shows a cross-sectional view of the configuration of the solid electrolytic capacitor according to the fifth embodiment of the present invention.

  The capacitor was manufactured in the same manner as in Example 2 except that the conductive adhesive 11 was applied to the gap between the pillow member bottom surface 52 and the anode terminal 6. Thereby, the contact area of the anode terminal 6 and the pillow member 5 increases, and ESR (equivalent series resistance) decreases.

  The above embodiments are merely illustrative of the invention and should not be construed as limiting the invention as claimed. The present invention can be freely modified within the scope of the claims and the scope of equivalent meanings.

BRIEF DESCRIPTION OF THE DRAWINGS (a) Perspective view of the solid electrolytic capacitor which concerns on 1st Example of this invention, (b) Bottom view, (c) It is sectional drawing cut | disconnected by the A-A 'line | wire. It is sectional drawing cut | disconnected by the (a) perspective view, (b) bottom view, (c) B-B 'line | wire of the solid electrolytic capacitor which concerns on 2nd Example of this invention. It is sectional drawing of the solid electrolytic capacitor which concerns on 3rd Example of this invention. It is sectional drawing of the solid electrolytic capacitor which concerns on 4th Example of this invention. It is sectional drawing of the solid electrolytic capacitor which concerns on 5th Example of this invention. It is a detailed sectional view of a capacitor element. It is (a) longitudinal cross-sectional view of the solid electrolytic capacitor which concerns on a prior art example, (b) It is sectional drawing cut | disconnected by C-C 'line | wire.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Anode body 2 Dielectric film layer 3 Cathode layer 3a Solid electrolyte layer 3b Cathode extraction layer 4 Anode extraction member 5 Pillow member 50 Conventional pillow member 51 Pillow member upper surface 52 Pillow member lower surface 6 Anode terminal 60 Conventional anode terminal 61 Anode terminal upper surface 62 Anode terminal lower surface 63 Conventional anode terminal upper surface 64 Conventional anode terminal lower surface 7 Cathode terminal 70 Conventional cathode terminal 71 Cathode terminal upper surface 72 Cathode terminal lower surface 73 Conventional cathode terminal upper surface 74 Conventional cathode terminal lower surface 8 Exterior resin 11 Conductive adhesive 12 Anode terminal cutting Notch 13 Insulation tape

Claims (4)

A capacitor element in which a dielectric film layer and a cathode layer are sequentially formed on the surface of an anode body on which an anode lead member is projected, an anode terminal in which the anode lead member is connected via a pillow member, and the cathode layer is connected A solid electrolytic capacitor comprising a cathode terminal formed and an exterior resin covering the capacitor element,
The pillow member has a flat surface,
The upper surface of the pillow member is connected to the anode lead member, the lower surface of the pillow member is connected to the anode terminal,
The upper surface of the pillow member is formed obliquely upward with respect to the upper surface of the anode terminal in the direction in which the anode lead-out member protrudes.
The capacitor element is directed in a direction in which the cathode terminal lower end portion of the capacitor element lower surface is in contact with the cathode terminal upper surface and the anode lead-out member protrudes with respect to the arrangement direction of the anode terminal and the cathode terminal. A solid electrolytic capacitor characterized by being disposed obliquely upward. The pillow member upper surface and the pillow member lower surface are substantially parallel to each other,
Regarding the arrangement direction of the anode terminal and the cathode terminal, the end closer to the anode terminal of the lower surface of the pillow member is separated from the upper surface of the anode terminal,
The solid electrolytic capacitor according to claim 1, wherein an end portion of the lower surface of the pillow member closer to the cathode terminal is connected to the upper surface of the anode terminal.   3. The projected portion projected from the end near the anode terminal of the lower surface of the capacitor element in a direction perpendicular to the anode terminal from the upper surface of the solid electrolytic capacitor overlaps the upper surface of the anode terminal. A solid electrolytic capacitor according to any one of the above. The solid electrolytic capacitor according to claim 1, wherein the pillow member and the anode terminal are connected by laser welding.

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