JP2008160062A - Surface mount electrolytic capacitor, and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface mount electrolytic capacitor for improving adhesion between an external resin case and an encapsulating case cover and hard to cause a change in characteristics, and to provide its manufacturing method. <P>SOLUTION: The surface mount electrolytic capacitor has, as the encapsulating case, a box-shaped resin case 2 with its upper opened having a positive electrode terminal 6 and a negative electrode terminal 7 incorporated in its bottom and the encapsulating case cover 1 for covering external surfaces of upper and sidewalls of the case 2. A protrusion 1a is formed on an internal ceiling surface of the encapsulating case cover 1, and thus a dent 1b is formed between an inner sidewall surface of the cover 1 and the protrusion 1a. The dent 1b and a sidewall upper end of the resin case 2 are fitted with each other via an adhesive 3. In addition, the protrusion 1a on the internal ceiling surface of the cover 1 holds the upper surface of a capacitor element 8, thereby preventing it from shifting in position. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a surface mount electrolytic capacitor and a method for manufacturing the same, and more particularly to a surface mount electrolytic capacitor with improved reliability and a method for manufacturing the same.

  The capacitor according to the prior art shown in FIG. 4 is called a three-terminal transmission line element. 4 shows a conventional surface mount type electrolytic capacitor, FIG. 4 (a) is a front sectional view of the outer case cover, FIG. 4 (b) is a bottom view of the outer case cover, and FIG. 4 (c) is a surface mount type electrolytic capacitor. It is a front sectional view of a capacitor.

  As disclosed in Patent Document 1, this surface mount type electrolytic capacitor according to the prior art uses a conductive functional polymer film as a solid electrolyte, and forms an anodic oxide coating layer on the surface of the valve action metal to provide a valve action. As a metal anode body, a conductive functional polymer film is formed so as to cover the center part of the surface of the anode oxide film layer of this anode body, a graphite layer is further formed around it, and a silver paste layer is further formed as a cathode layer. After the sequential formation, the anode portion at the end of the capacitor element 8 was formed through the conductive spacer 4, and the cathode portion at the center of the capacitor element 8 was formed directly in the resin case 2 with the conductive adhesive 5. After being connected to the anode terminal 6 and the cathode terminal 7, the exterior case cover 1 is fixed with an adhesive 3.

JP 2006-128247 A

  In the conventional surface mount type electrolytic capacitor, a capacitor element is mounted in a resin case, connected to and fixed to a cathode terminal, and then an outer case cover is fixed to the resin case and sealed.

  Each fixing requires drying and curing using a conductive adhesive and adhesive, so each fixing jig and drying oven are required, and the manufacturing process equipment and lead time are also required. It was. In addition, the adhesive distribution varies when the resin case and the exterior case cover are joined, and the adhesiveness or residual strain may vary. Accordingly, an object of the present invention is to provide a surface-mount type electrolytic capacitor that can reduce lead time and simplify the apparatus, and can improve hermeticity and hardly cause changes in characteristics, and a method for manufacturing the same.

  In order to solve the above problems, a surface mount electrolytic capacitor of the present invention includes a plate-like capacitor element having an anode portion at an end portion and a cathode portion at a central portion, or a capacitor element laminate formed by laminating the capacitor elements. In the surface mount type electrolytic capacitor in which the anode terminal connected to the anode part and the cathode terminal connected to the cathode part are packaged by an exterior case, the exterior case has the anode terminal and the cathode terminal at the bottom part. And a box-shaped resin case that is open at the top, and an exterior case cover that covers at least part of the outer surface of the side wall along with the upper side of the resin case, and a convex portion is formed on the inner ceiling surface of the exterior case cover. By being formed, a concave portion is formed between the side wall surface inside the outer case cover and the convex portion, and the concave portion is fitted to the upper end portion of the side wall of the resin case. Characterized in that it has been.

  Further, the capacitor element or the capacitor element laminated body is pressed by a lower surface of a convex portion provided on an inner ceiling surface of the exterior case cover.

  Further, the lower surface of the convex portion provided on the inner ceiling surface of the outer case cover holds down the anode part and the cathode part of the capacitor element or the capacitor element laminate, and the resin case and the outer case cover are fitted. The anode part and the anode terminal, and the cathode part and the cathode terminal are respectively joined by a conductive adhesive.

  Moreover, the convex part of the said exterior case cover may be an integral thing of the same material as the said exterior case cover, may consist of an elastic body, and may be connected to the said exterior case cover.

  The method for manufacturing a surface mount electrolytic capacitor according to the present invention includes a step of manufacturing a plate-shaped capacitor element having an anode portion at an end portion and a cathode portion at a central portion, and a conductive property in the anode portion of the capacitor element. A conductive adhesive on the anode terminal and the cathode terminal of the box-shaped resin case in which the anode terminal is disposed at both ends of the bottom surface, the cathode terminal is disposed at the center of the bottom surface, and the upper side is opened. The capacitor element is disposed on the upper surface of the resin case, adhesive is applied to the upper surface of the resin case, and the convex portion of the outer case cover provided with a convex portion on the upper surface holds the anode and cathode portions of the capacitor element. And a step of fitting the outer case cover to the resin case, and a step of simultaneously curing the conductive adhesive and the adhesive.

  Furthermore, the method for manufacturing a surface mount electrolytic capacitor according to the present invention includes a step of manufacturing a plate-shaped capacitor element having an anode portion at an end portion and a cathode portion at a central portion, and an anode portion of the capacitor element. A step of forming a capacitor element laminate by connecting conductive spacers to form a capacitor element laminate, and a box-like shape in which an anode terminal is disposed at both ends of a bottom surface, a cathode terminal is disposed at a center portion of the bottom surface and an upper portion is opened The capacitor element laminate is disposed on the anode terminal and the cathode terminal of the resin case via a conductive adhesive, the adhesive is applied to the upper end surface of the resin case, and a convex portion is provided inside the upper surface. The step of pressing the anode part and the cathode part of the capacitor element laminate by the convex part of the outer case cover, and fitting the outer case cover to the resin case; and the conductive adhesive and the front Characterized in that it comprises a step of curing the adhesive at the same time.

  In the surface mount electrolytic capacitor of the present invention, since the resin case and the outer case cover are fitted and bonded with an adhesive, the degree of adhesion of the outer case is increased, and the reliability can be improved by improving the sealing property. . In addition, when the anode part and the cathode part of the capacitor element are pressed by the convex part of the exterior case cover and joined to the anode terminal and the cathode terminal with a conductive adhesive, a more reliable connection can be achieved.

  In the method for manufacturing a surface mount electrolytic capacitor according to the present invention, the resin case and the outer case cover are fixed in a state where the capacitor element is held down, so that the conductive bonding in the conventional connection between the capacitor element and the resin case is performed. The curing operation of the agent and the curing operation of the adhesive of the resin case and the exterior case cover can be performed at the same time, so that the workability can be improved and the equipment can be saved.

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

(Embodiment 1)
FIG. 1 shows a surface-mounted electrolytic capacitor according to Embodiment 1 of the present invention, FIG. 1 (a) is a front sectional view of an exterior case cover, FIG. 1 (b) is a bottom view of the exterior case cover, and FIG. c) is a front sectional view of the entire surface mount type electrolytic capacitor.

  First, the conductive spacer 4 is connected to the anode part of the flat capacitor element 8 to produce a multilayer capacitor element in which they are laminated. Next, as one of the exterior cases, the anode terminal 6 is disposed at both ends of the bottom surface portion, the cathode terminal 7 is disposed at the center of the bottom surface portion, and is integrally formed with the anode terminal 6 and the cathode terminal 7 by injection molding or the like. A box-shaped resin case 2 is produced, and a conductive adhesive 5 connects between the cathode layer of the capacitor element 8 and the cathode terminal 7 and between the spacer 4 and the anode terminal 6 inside thereof.

  Next, an adhesive 3 is applied to the upper end surface of the side wall of the resin case 2, and as the other of the exterior case, a rectangular convex portion 1a is provided on the inner ceiling surface, and a concave portion 1b is provided around it. The upper end of the side wall of the resin case 2 is fitted into the recess 1 b of the case cover 1.

  In this way, as shown in FIG. 1C, the resin case 2 and the outer case cover 1 can be bonded and fixed in a state where the capacitor element 8 is held by the convex portion 1a. (1) Curing operation of the conductive adhesive 5 for connecting the capacitor element 8 to the anode terminal 6 and the cathode terminal 7 on the bottom surface of the resin case 2, and (2) bonding and fixing the resin case 2 and the outer case cover 1 together. It is possible to simultaneously perform the curing operation of the adhesive 3 for use.

  In addition, by fitting the upper end of the side wall of the resin case 2 into the recess 1b inside the outer case cover 1 via the adhesive 3, the degree of adhesion can be increased and the reliability can be improved by improving the sealing performance.

(Embodiment 2)
2 shows a surface mount electrolytic capacitor according to Embodiment 2 of the present invention. FIG. 2 (a) is a front sectional view of the outer case cover, FIG. 2 (b) is a bottom view of the outer case cover, and FIG. c) is a front sectional view of the entire surface mount type electrolytic capacitor.

  In the central portion of the inner ceiling surface of the outer case cover 1 of the present embodiment, a convex portion that presses the capacitor element 8 from the upper side is not formed, and a concave shape 1b is formed along the edge of the ceiling surface. The convex portion 1c is formed, and the upper end portion of the side wall of the resin case 2 is fitted into the concave portion 1b, and is bonded and fixed via the adhesive 3.

  Using this outer case cover 1 and the same resin case 2 as in the first embodiment, first, a laminate of the capacitor element 8 is applied to the anode terminal 6 and the cathode terminal 7 on the inner bottom surface of the resin case 2 with a conductive adhesive. 5 to connect. Next, the surface mount type electrolytic capacitor of this Embodiment is obtained by fitting the upper end part of the side wall of the resin case 2 in the recessed part 1b of the exterior case cover 1 via the adhesive 3, and joining and fixing.

  Also according to the present embodiment, it is possible to produce a surface-mount type electrolytic capacitor that enhances the adhesion of the outer case and hardly changes its characteristics without strictly controlling the application amount of the adhesive 3. Further, the outer diameter tolerance of the product can be reduced.

(Embodiment 3)
3 shows a surface-mounted electrolytic capacitor according to Embodiment 3 of the present invention. FIG. 3 (a) is a front sectional view of the outer case cover, FIG. 3 (b) is a bottom view of the outer case cover, and FIG. c) is a front sectional view of a surface mount electrolytic capacitor.

  First, conductive spacers 4 are connected to the anode portions at both ends of the plate-like capacitor element 8, and a multilayer capacitor element is produced by laminating them if necessary. Next, the anode terminal 6 is disposed at both ends of the bottom surface portion, the cathode terminal 7 is disposed at the center of the bottom surface portion, and the box-shaped resin case 2 in which the anode terminal 6 and the cathode terminal 7 are integrally formed by injection molding or the like The element 8 is mounted with the cathode portion on the conductive adhesive 5 on the cathode terminal 7 and the anode portion on the conductive adhesive 5 on the anode terminal 6 via the conductive spacer 4.

  Next, the adhesive 3 is applied to the upper end of the side wall of the resin case 2, and the resin case 2 is formed in the recess 1b of the outer case cover 1 having the protrusions 1a and 1c on the inside of the upper surface and the recess 1b around the protrusions 1a and 1c. Mating. When fitting the outer case cover 1, the convex portion 1 a at the center of the outer case cover is the cathode portion of the capacitor element 8, and the convex portions 1 c at both ends of the outer case cover are the anode portions including the conductive spacers 4. It is structured to hold each at the same time. Then, by simultaneously drying the adhesive 3 for the exterior case cover and the conductive adhesive 5 for the capacitor element, it is possible to simplify the jigs and tools during drying and to shorten the drying time. In addition, the convex part of an exterior case cover can be produced by shaping | molding by injection molding etc. as an integral thing with an exterior case cover. Further, the convex portion can be made of an elastic body such as silicone resin or fluorine rubber, and can be joined to the inside of an outer case cover molded into a box shape such as epoxy resin or PPS (polyphenylene sulfide) resin. When an elastic body is used for the convex portion, it can be manufactured without strictly controlling the dimensional accuracy of the step between the convex portion 1a at the central portion and the convex portion 1c at both ends.

  The surface mount type electrolytic capacitor according to the present invention can be applied to an electronic component in which an electrode is formed on the bottom surface of a product of a type that is surface mounted on a printed board.

1 shows a surface-mounted electrolytic capacitor according to Embodiment 1 of the present invention, FIG. 1A is a front sectional view of an exterior case cover, FIG. 1B is a bottom view of the exterior case cover, and FIG. The front sectional view of the whole mounting type electrolytic capacitor. 2 shows a surface-mounted electrolytic capacitor according to Embodiment 2 of the present invention, in which FIG. 2A is a front sectional view of the outer case cover, FIG. 2B is a bottom view of the outer case cover, and FIG. The front sectional view of the whole mounting type electrolytic capacitor. 3 shows a surface-mounted electrolytic capacitor according to Embodiment 3 of the present invention, in which FIG. 3 (a) is a front sectional view of the outer case cover, FIG. 3 (b) is a bottom view of the outer case cover, and FIG. The front sectional view of a mounting type electrolytic capacitor. FIG. 4A is a front sectional view of an exterior case cover, FIG. 4B is a bottom view of the exterior case cover, and FIG. 4C is a front view of the surface mount electrolytic capacitor. Sectional drawing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Exterior case cover 1a Convex part 1b Concave part 1c Convex part 2 Resin case 3 Adhesive 4 Spacer 5 Conductive adhesive 6 Anode terminal 7 Cathode terminal 8 Capacitor element

Claims (7)

A plate-shaped capacitor element having an anode part at the end and a cathode part at the center or a capacitor element laminate formed by laminating the capacitor element, an anode terminal connected to the anode part, and a cathode part In the surface mount type electrolytic capacitor in which the connected cathode terminal is sheathed by the exterior case,
The outer case includes a box-shaped resin case in which the anode terminal and the cathode terminal are incorporated in the bottom surface and opened upward, and an outer case cover that covers at least a part of the outer surface of the side wall along with the upper side of the resin case. And
By forming a convex portion on the inner ceiling surface of the outer case cover, a concave portion is formed between the side wall surface on the inner side of the outer case cover and the convex portion, and the upper end portion of the side wall of the resin case. And a surface mount type electrolytic capacitor characterized by being fitted.   The surface mount type electrolytic capacitor according to claim 1, wherein the capacitor element or the capacitor element laminated body is pressed by a lower surface of a convex portion provided on an inner ceiling surface of the exterior case cover.   The lower surface of the convex portion provided on the inner ceiling surface of the outer case cover holds down the anode part and the cathode part of the capacitor element or the capacitor element laminate, and the resin case and the outer case cover are fitted and bonded. 3. The surface mount type electrolytic capacitor according to claim 2, wherein the anode portion and the anode terminal, and the cathode portion and the cathode terminal are respectively joined by a conductive adhesive.   The surface mount type electrolytic capacitor according to any one of claims 1 to 3, wherein the convex portion of the outer case cover is an integral part made of the same material as the outer case cover.   The surface mount electrolytic capacitor according to any one of claims 1 to 3, wherein the convex portion of the outer case cover is made of an elastic body and connected to the outer case cover.   A step of manufacturing a plate-like capacitor element having an anode portion at the end and a cathode portion at the center, a step of connecting a conductive spacer to the anode portion of the capacitor element, and an anode terminal at both ends of the bottom surface The anode terminal of the box-shaped resin case having the cathode terminal disposed at the center of the bottom surface and the upper part being open, and the capacitor element disposed on the cathode terminal via a conductive adhesive, and the upper end surface of the resin case A step of applying an adhesive to the outer surface of the outer case cover, and pressing the capacitor element with the convex portion of the outer case cover provided with a convex portion inside the upper surface, and fitting the outer case cover to the resin case; and the conductive bonding And a step of simultaneously curing the adhesive and the adhesive. A method for producing a surface mount electrolytic capacitor, comprising:   A step of manufacturing a plate-shaped capacitor element having an anode portion at an end portion and a cathode portion at a central portion; and connecting the conductive spacer to the anode portion of the capacitor element to laminate the capacitor element, A step of forming a laminated body, and a conductive adhesive on the anode terminal and the cathode terminal of the box-shaped resin case in which the anode terminal is disposed at both ends of the bottom surface, the cathode terminal is disposed at the center of the bottom surface, and the top is opened Through which the capacitor element laminate is disposed, the adhesive is applied to the upper end surface of the resin case, and the capacitor element laminate is pressed by the convex portion of the exterior case cover provided with the convex portion on the inner side of the upper surface, A surface mount electrolytic capacitor comprising: fitting the outer case cover into the resin case; and curing the conductive adhesive and the adhesive simultaneously. The method of production.

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