Capacitor and manufacturing method thereof

Abstract

To provide a structure of a capacitor that enhances the adhesion strength with a wiring board, and suppress an increase in the manufacturing load of this capacitor.SOLUTION: A capacitor main body (4) includes an exterior case (12), a pedestal (6), a sealing member (16) having a first insertion hole portion (24-1, 24-2) and attached to the opening of the exterior case, and a terminal lead (18-1, 18-2) having a bent portion (20) and an exposed terminal portion (22). The pedestal (6) includes a second insertion hole portion (26-1, 26-2) through which the terminal lead is inserted, and a guide groove (28-1, 28-2) formed on a board mounting surface and where the exposed terminal is placed. A resin layer (8-1, 8-2) is arranged between the pedestal and the sealing member, and arranged in a part of the inside of an insertion hole formed by the first insertion hole portion and the second insertion hole portion. A fixing resin (10) is arranged between both side surfaces of the exposed terminal portion and the edge of the guide groove, and is integrally formed with the resin layer.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a capacitor that can be mounted on a wiring board such as a circuit board, and a method for manufacturing the same. [Background technology]

[0002] To mount a capacitor on a wiring board such as a circuit board, the capacitor is provided with a base, for example. The terminal leads of the capacitor are drawn out to the outer surface of the base (i.e. the board mounting surface), bent, and soldered to the wiring board, for example. Capacitors used for this type of mounting are called surface-mount capacitors. Surface-mount capacitors are highly versatile and are used, for example, in automobiles.

[0003] When a capacitor is installed outdoors, such as inside an automobile, the environmental temperature around the capacitor increases. For this reason, the capacitor needs to withstand high-temperature environments. For example, a resin layer is formed between the sealing body and the base of the capacitor to improve the hermeticity of the capacitor (for example, Patent Document 1). With this configuration, the heat resistance of the capacitor can be improved. In a capacitor provided with this base, an insertion hole is formed in the base, and the terminal lead of the capacitor is disposed outside the base, i.e., on the board mounting surface side, through the insertion hole.

[0004] It is known that the tip of the terminal lead that passes through the insertion hole of the base is fitted into a recess of the base in which ribbon solder or cream solder is sandwiched (for example, Patent Document 2). In a capacitor having such a configuration, insufficient solder connection is prevented. In other words, the surface of the terminal lead facing the board and the side surface of the terminal lead are connected to the board by solder, and the solder connection between the capacitor and the board is strengthened. There are the following two ideas (1) and (2) regarding the connection between the capacitor and the board. (1) To strengthen the connection between the capacitor and the board, it is better to pre-apply solder to the sides of the terminal leads. (2) To strengthen the connection between the capacitor and the board, it is better to leave the sides of the terminal leads exposed so that the solder will adhere to the sides of the terminal leads when mounted on the board. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 60-245121 [Patent Document 2] Japanese Patent Application Laid-Open No. 60-148105 Summary of the Invention [Problem to be solved by the invention]

[0006] Meanwhile, solder connection contributes to mechanical connection between the wiring board and the terminal lead. Whether the solder connection is sufficient or not is generally influenced by the amount and area of ​​solder adhesion, etc. Whether the solder connection is sufficient or not is generally a problem of the connection structure between the wiring board and the terminal lead, and is influenced by the soldering process such as the reflow process.

[0007] The hardness and shape of solder changes when heated during the soldering process, so even if solder is provided near the terminal leads, capacitor manufacturers cannot check or inspect the final state of the board-mounted portion of the capacitor before it is mounted on the board at the time of sale.

[0008] In capacitors where solder is provided by simple clamping, care must be taken to prevent, for example, the solder from falling off or peeling off, and in capacitors where ribbon solder is provided by clamping, care must be taken to prevent, for example, the terminal leads from being pushed up by the restoring force of the ribbon solder.

[0009] Patent Documents 1 and 2 do not disclose or suggest such a problem, and the configurations disclosed in Patent Documents 1 and 2 cannot solve such a problem.

[0010] Therefore, the first object of the technology disclosed herein is to provide a capacitor structure that enhances the adhesive strength to a wiring board, while suppressing an increase in the manufacturing load of the capacitor. Here, "adhesive strength" does not mean the strength of a simple connection determined by the solder, but is a term that means the adhesive strength of the capacitor to the wiring board, i.e., shear strength.

[0011] A second object of the technique of the present disclosure is to make it possible to confirm at the time of sale that a capacitor is in substantially the same condition as the capacitor after it has been mounted on a wiring board, for example. [Means for solving the problem]

[0012] In order to achieve the above object, according to a first aspect of the present disclosure, a capacitor includes a capacitor body, a base, a resin layer, and a fixing resin. The capacitor body includes an exterior case, a sealing member having a first insertion hole portion attached to an opening of the exterior case, and a terminal lead leading out from the first insertion hole portion and having a bent portion and an exposed terminal portion. The base is installed on the sealing member side of the capacitor body and has a second insertion hole portion through which the terminal lead is inserted, and a guide groove formed on a board mounting surface and in which the exposed terminal portion is disposed. A resin layer is disposed between the base and the sealing member, and in a part of the inside of the insertion hole formed by the first insertion hole portion and the second insertion hole portion. The fixing resin is disposed between both side surfaces of the exposed terminal portion of the terminal lead and edges of the guide groove, and is formed integrally with the resin layer.

[0013] In the above capacitor, the fixing resin may be disposed along the exposed terminal portion of the terminal lead.

[0014] In the above capacitor, the resin layer may cover a portion of the bent portion.

[0015] In the above capacitor, the surface of the fixing resin may be at the same position as the substrate mounting surface or may be located on the inner side of the base than the substrate mounting surface.

[0016] In the above capacitor, the central axis of the terminal lead may be disposed closer to the outer edge of the base than the center of the opening of the insertion hole.

[0017] In the above capacitor, the base may further have a connection groove on the board mounting surface, the connection groove connecting the second insertion hole portion on the anode side and the second insertion hole portion on the cathode side.

[0018] In order to achieve the above-mentioned object, according to a second aspect of the present disclosure, a method for manufacturing a capacitor includes the steps of: preparing a capacitor body including an outer case, a sealing member having a first insertion hole portion attached to an opening of the outer case, and a terminal lead extending from the first insertion hole portion; preparing a base having a second insertion hole portion and a guide groove formed on a substrate mounting surface; installing the base on the sealing member side of the capacitor body and inserting the terminal lead into the second insertion hole portion to expose it on the substrate mounting surface side; bending the terminal lead to form a bent portion and an exposed terminal portion on the terminal lead and positioning the exposed terminal portion in the guide groove; forming a resin layer between the base and the sealing member and in a portion of the inside of an insertion hole formed by the first insertion hole portion and the second insertion hole portion; and forming a fixing resin integral with the resin layer between both side surfaces of the exposed terminal portion and an edge of the guide groove.

[0019] In the step of forming the fixing resin, the viscosity of the resin may be reduced by a heat treatment, and the resin may move from inside the insertion hole to the guide groove to form the fixing resin.

[0020] In the method for manufacturing a capacitor, the heat treatment may harden the resin between the base and the sealing material and the resin inside the insertion hole. Effect of the Invention

[0021] According to the technology of the present disclosure, any of the following effects can be obtained.

[0022] (1) The integrally formed resin layer and fixing resin enhance the integrity of the capacitor body and the base and also strengthen the bonding strength of the terminal leads, especially the exposed terminal portions, to the base. This makes it possible to increase the bonding strength of the capacitor, for example.

[0023] (2) Since the fixing resin is formed integrally with the resin layer, the increase in the manufacturing load of the capacitor can be suppressed.

[0024] (3) Because the fixing resin is disposed between the exposed terminals and the edge of the guide groove, there is little change in the connection portion of the capacitor to the wiring board during the capacitor connection process, such as the reflow process. Therefore, it is possible to check the approximate final state of the capacitor when the capacitor manufacturing is completed. Capacitors that change little after manufacturing are beneficial, for example, from the standpoint of quality assurance. [Brief description of the drawings]

[0025] [Figure 1] FIG. 2 is a diagram illustrating an example of a capacitor according to the first embodiment. [Diagram 2] FIG. 2 is a partial cross-sectional view of a capacitor. [Diagram 3] FIG. [Figure 4] 1A to 1C are diagrams illustrating an example of a manufacturing process for a capacitor. [Diagram 5] FIG. 2 is a diagram illustrating an example of a capacitor according to the first embodiment. [Figure 6] FIG. 11 is a diagram illustrating an example of a capacitor according to a second embodiment. [Figure 7]FIG. 11 is a diagram illustrating an example of a capacitor according to a third embodiment. [Figure 8] FIG. 13 is a diagram showing test results of sticking properties of the capacitor according to the embodiment. [Figure 9] FIG. 13 is a diagram showing test results of sticking properties of a capacitor according to a comparative example. [Figure 10] FIG. 13 is a diagram illustrating an example of a capacitor according to a second embodiment. [Figure 11] FIG. [Figure 12] FIG. 13 is a bottom view of a base of a capacitor according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Hereinafter, embodiments will be described with reference to the drawings. First embodiment

[0027] FIG. 1A is a cross-sectional view showing an example of a capacitor according to the first embodiment, and FIG. 1B is a partial bottom view of the capacitor. In FIG. 1A, a part of the capacitor body is omitted. FIG. 2A and FIG. 2B are partial enlarged views of FIG. 1A. FIG. 3A and FIG. 3B are perspective views of a pedestal. FIG. 3A shows a body installation surface (i.e., a surface portion of the pedestal on the sealing member side) installed on the capacitor body. FIG. 3B shows an opposing surface to the body installation surface (i.e., an outer surface or a board mounting surface of the pedestal). The configurations shown in FIG. 1 to FIG. 3 are examples, and the technology of the present disclosure is not limited to such configurations. In this specification, the capacitor body side is treated as "upper" and the pedestal side is treated as "lower", and the "plane" and "bottom" on the drawings are defined.

[0028] Capacitor 2 is an example of an electronic component, such as an electrolytic capacitor or an electric double layer capacitor. Capacitor 2 includes a capacitor body 4, a base 6, resin layers 8-1 and 8-2, and a fixing resin 10. Base 6 is installed on capacitor body 4, resin layer 8-1 is disposed in the gap between base 6 and capacitor body 4, and resin layer 8-2 is disposed inside second insertion holes 26-1 and 26-2 formed in base 6. Capacitor 2 can be mounted on a wiring board such as a circuit board.

[0029] The capacitor body 4 can be used as a single capacitor. The capacitor body 4 includes an outer case 12, a capacitor element 14, and a sealing member 16. The capacitor element 14 is sealed in the outer case 12, and the sealing member 16 is attached to the opening of the outer case 12.

[0030] The outer case 12 is, for example, a cylindrical aluminum case with a bottom. The tip of the opening of the outer case 12 is bent at a substantially right angle, so that the end of the outer case 12 opposite the bottom (hereinafter referred to as the "open end") has a flat surface.

[0031] Capacitor element 14 is a wound element in which a separator is interposed between an anode foil and a cathode foil, and terminal leads 18-1 and 18-2 extend from the same element surface. Capacitor element 14 is impregnated with an electrolyte.

[0032] The terminal leads 18-1 and 18-2 are formed of, for example, a metal having good electrical conductivity. The terminal lead 18-1 is an anode side terminal and includes a lead portion drawn from the anode foil of the capacitor element 14 and a terminal portion mounted on a wiring board. The lead portion and the terminal portion are connected and integrated by welding or the like. The terminal lead 18-2 is a cathode side terminal and includes a lead portion drawn from the cathode foil of the capacitor element 14 and a terminal portion mounted on a wiring board. As with the terminal lead 18-1, the lead portion and the terminal portion are connected and integrated by welding or the like. The lead portion is, for example, cylindrical, and the terminal portion has, for example, a surface side mounted on a wiring board that is flattened and has a rectangular cross section. The terminal portions of the terminal leads 18-1 and 18-2 are bent in opposite directions. The terminal leads 18-1 and 18-2 include a bent portion 20 formed by bending and an exposed terminal portion 22.

[0033] The sealing member 16 is formed of, for example, insulating rubber. The sealing member 16 has first insertion holes 24-1, 24-2 (hereinafter referred to as "insertion holes 24-1, 24-2") at positions corresponding to the terminal leads 18-1, 18-2. The terminal leads 18-1, 18-2 of the capacitor element 14 pass through the insertion holes 24-1, 24-2 of the sealing member 16 and are exposed to the outside of the capacitor body 4.

[0034] The base 6 is disposed on the sealing material 16 side of the capacitor body 4. The base 6 is formed of an insulating plate such as an insulating synthetic resin. The insulating synthetic resin may have sufficient heat resistance to withstand the heat applied when mounting the capacitor on a wiring board, and may be, for example, a polyester resin such as polybutylene terephthalate (PBT), polybutylene naphthalate (PBN), or polyethylene terephthalate (PET), a polyamide resin such as nylon, polyphenylene sulfide (PPS), polyphenylene oxide (PPO), urea resin, liquid crystal polymer (LCP), phenol resin, or epoxy resin. The base 6 includes second insertion hole portions 26-1 and 26-2 (hereinafter referred to as "insertion hole portions 26-1 and 26-2"), guide grooves 28-1 and 28-2, a protrusion 30, and a peripheral wall 32. As shown in FIG. 3A, the base 6 has a support protrusion 34, a resin injection hole 36, a through hole 38, and a shielding portion 40, and as shown in FIG. 3B, it has step portions 42, 44, and a support portion 46.

[0035] The insertion holes 26-1, 26-2 are holes formed at positions corresponding to the terminal leads 18-1, 18-2. The pair of terminal leads 18-1, 18-2 protruding from the capacitor body 4 penetrate a pair of insertion holes 26-1, 26-2 formed in the base 6 and are drawn out to the outer surface side of the base 6, that is, the board mounting surface side of the base 6. The insertion holes 26-1, 26-2, together with the insertion holes 24-1, 24-2, form insertion holes for passing the terminal leads 18-1, 18-2 through.

[0036] The guide grooves 28-1 and 28-2 are formed on the substrate mounting surface of the base 6 and extend from the insertion holes 26-1 and 26-2 to the outside (the outer edge side of the base 6). The exposed terminal portions 22 of the bent terminal leads 18-1 and 18-2 are arranged in the guide grooves 28-1 and 28-2. Therefore, the guide grooves 28-1 and 28-2 guide the terminal portions of the terminal leads 18-1 and 18-2. The guide grooves 28-1 and 28-2 are formed by grooves on the substrate mounting surface of the base 6. The guide grooves 28-1 and 28-2 may be formed by a plurality of guide protrusions having a length formed on the outside of the terminal portions of the terminal leads 18-1 and 18-2. The guide grooves 28-1 and 28-2 or the guide grooves formed by a plurality of guide protrusions contribute to ensuring the stability of the capacitor 2 when mounted.

[0037] The exposed terminal portions 22 of the terminal leads 18-1, 18-2 are spaced apart from the edges of the guide grooves 28-1, 28-2. Therefore, the fixing resin 10 is disposed between both side surfaces of the exposed terminal portions 22 and the edges of the guide grooves 28-1, 28-2 to fix the exposed terminal portions 22 to the board mounting surface of the base 6. In order to prevent the guide grooves 28-1, 28-2 from interfering with the mounting of the capacitor 2, the exposed surfaces of the exposed terminal portions 22 protrude from the guide grooves 28-1, 28-2 and are disposed outside the guide grooves 28-1, 28-2. This exposed surface faces the surface of the wiring board when mounted on the board.

[0038] The protrusion 30 is disposed on the body installation surface of the base 6. The protrusion 30 is formed around the insertion holes 26-1 and 26-2 and surrounds the insertion holes 26-1 and 26-2. The protrusion 30 faces the sealing member 16 and separates the resin layer 8-1 adjacent to the protrusion 30 from the insertion holes 26-1 and 26-2. The height of the protrusion 30 may be set to, for example, the height difference H (B in FIG. 2) between the outer surface of the sealing member 16 and the body installation surface of the base 6, or may be lower or higher than the height difference H. When the height of the protrusion 30 is the height difference H, the open end of the exterior case 12 and the base 6 come into contact with each other, and the protrusion 30 of the base 6 comes into contact with the sealing member 16. The exterior case 12 and the protrusion 30 function as supports, so that the installation of the base 6 is stable and the capacitor body 4 is supported at both the periphery and the center. In addition, the protrusion 30 in contact with the sealing member 16 can prevent the resin injected between the base 6 and the sealing member 16 for forming the resin layers 8-1, 8-2, or for forming the resin layers 8-1, 8-2 and the fixing resin 10, from excessively penetrating into the insertion hole portions 26-1, 26-2.

[0039] As shown in Fig. 3A, the protruding portion 30 has, for example, a substantially rectangular shape with a constriction in the longitudinal center. The protruding portion 30 has a recessed portion 48 in the longitudinal center, which forms the constriction. The protruding portion 30 has a flat portion 50 at each end in the longitudinal direction.

[0040] The protrusion 30 has grooves 52, 54 on the surface facing the sealing material 16. Groove 52 is formed so as to partially lower the height of an intermediate portion between insertion hole 26-1 and insertion hole 26-2, and extends between the resin injection hole 36 side and the through hole 38 side to form a resin passage. The flow rate of resin flowing through groove 52 can be adjusted depending on the width of groove 52.

[0041] The grooves 54 extend from the flat portion 50 of the protruding portion 30 to the through-hole portions 26-1 and 26-2 to form an air passage or a resin passage. The grooves 54 can guide the air or resin pushed out by the resin injection to the through-hole portions 26-1 and 26-2. The grooves 54 may allow a part of the injected resin to pass through and reach the through-hole portions 26-1 and 26-2, for example, to form the resin layer 8-2 and the fixing resin 10. The width, depth, installation interval, or number of the grooves 54 is appropriately set, for example, taking into consideration the amount of air or resin passing through. The grooves 54 are formed, for example, only on the surface of the protruding portion 30 on the through-hole 38 side. Therefore, the resin is prevented from flowing directly through the grooves 54 to the through-hole portions 26-1 and 26-2. In other words, the resin injected from the resin injection hole 36 flows due to the injection pressure into the space between the sealing member 16 and the base 6 on the side of the through hole 38 of the protrusion 30, and then the resin is pushed into the groove portion 54 by the pressing force of the resin filled in that space, so that the resin can be flowed into the groove portion 54 at a pressure lower than the injection pressure.

[0042] The peripheral wall 32 is disposed on the periphery of the base 6, outside the open end of the outer case 12, and surrounds the open end of the outer case 12. The inner surface of the peripheral wall 32 has a circular shape so as to fit along the outer periphery of the bottomed cylindrical outer case 12. The peripheral wall 32 may be higher than the protruding portion 30, or may be the same height as the protruding portion 30, or may be lower than the protruding portion 30.

[0043] The support protrusion 34 is an example of a protrusion that supports the open end of the outer case 12, and is adjacent to the resin layer 8-1 and partially formed at a position where the base 6 contacts the open end of the outer case 12. As shown in FIG. 3A, the support protrusion 34 is formed on the main body installation surface of the base 6, and inside the base 6 relative to the peripheral wall 32. The support protrusion 34 has a circular arc shape with a width, and covers the outside of the resin injection hole 36 and the protrusion 30 in a circular arc shape. In addition, although not shown, another support protrusion different from the support protrusion 34 is formed between the through hole 38 and the peripheral wall 32 at a position that contacts the open end of the outer case 12. The other support protrusion has a circular shape and is arranged outside the through hole 38. At the portion where support protrusion 34 and the other support protrusions are formed, the open end of outer case 12 comes into contact with support protrusion 34 or the other support protrusions, and at the portion where support protrusion 34 and the other support protrusions are separated, the open end of outer case 12 is separated from base 6, forming a gap between the open end of outer case 12 and base 6. This gap between the open end of outer case 12 and base 6 forms a resin path for flowing resin between the peripheral wall 32 of base 6 and the outer circumferential surface of outer case 12.

[0044] The resin injection hole 36 is an example of an insertion hole used for injecting resin, and is formed equidistant from the insertion hole portions 26-1, 26-2.

[0045] The through hole 38 is formed at the end portion where the resin finally flows in during resin injection, for example, and is used to check that the resin has reached the end portion along the resin injection path. The through hole 38 is also used to exhaust air pushed out by the resin injection, and the through hole 38 makes it easy to check the resin filling state and also to exhaust air.

[0046] The shielding portion 40 is disposed around the through hole 38, between the through hole 38 and the resin injection hole 36. The shielding portion 40 prevents the resin injected through the resin injection hole 36 from penetrating into the through hole 38 from the resin injection hole 36 side of the through hole 38. In other words, the shielding portion 40 prevents the through hole 38 from being filled with resin before the resin spreads throughout the formation region of the resin layer 8-1.

[0047] 3B, step 42 is formed on the board mounting surface of base 6 around resin injection hole 36. Step 42 is used, for example, for aligning a resin injection device that is connected to resin injection hole 36 during resin injection. Step 42 provides a space to prevent resin near resin injection hole 36 from protruding beyond the board mounting surface of base 6.

[0048] 3B, the step portion 44 is the board mounting surface of the base 6 and is formed around the through hole 38. The step portion 44 provides a space to prevent the resin in the vicinity of the through hole 38 from protruding beyond the board mounting surface of the base 6.

[0049] As shown in Fig. 3B, support portion 46 is formed on the board mounting surface of base 6 near a corner of base 6. Support portion 46 can stabilize the attitude of capacitor 2 by point contact when capacitor 2 is mounted on the wiring board. When support portion 46 contacts the wiring board, exposed terminal portions 22 of terminal leads 18-1, 18-2 are slightly separated from the wiring board. This gap between exposed terminal portions 22 and the wiring board ensures the thickness of solder required for connection.

[0050] The resin layer 8-1 is provided on the outside of the protruding portion 30 and on the inside of the open end of the exterior case 12, between the base 6 and the sealing material 16. This resin layer 8-1 adheres the capacitor body 4 and the base 6 together, and seals the outer surface of the sealing material 16 together with the base 6. In addition, the resin layer 8-1 strengthens the bonding force of the base 6 to the exterior case 12 and the sealing material 16, thereby improving the unity of the capacitor body 4 and the base 6.

[0051] The resin layer 8-2 is provided inside the insertion hole portions 26-1, 26-2, in other words, in a part of the inside of the insertion hole formed by the insertion hole portions 24-1, 24-2 and the insertion hole portions 26-1, 26-2. This resin layer 8-2 fills the gap between the inner surface of the insertion hole portions 26-1, 26-2 and the terminal leads 18-1, 18-2. Therefore, the sealing property is improved and the amount of gas passing through the insertion hole portions 26-1, 26-2 is suppressed. In addition, the resin layer 8-2 strengthens the bonding force of the base 6 to the terminal leads 18-1, 18-2, and enhances the unity of the capacitor body 4 and the base 6. For example, the resin injected from the resin injection hole 36 reaches the insertion hole portions 26-1, 26-2, and the resin layer 8-2 is formed. In other words, the resin layer 8-2 is formed during the formation process of the resin layer 8-1, and the manufacturing load is suppressed. However, resin layer 8-2 may be formed by adding resin from the substrate mounting surface of base 6. If resin layer 8-2 is formed from injected resin in some of the manufactured capacitors 2, the addition of resin from the substrate mounting surface can be suppressed, and the manufacturing load can be reduced.

[0052] The resin forming the resin layers 8-1, 8-2 is, for example, a sealing resin that seals the outside of the sealing member 16, and is in a liquid state when filled, but solidifies after filling. When filled, the liquid resin fills the gap between the capacitor body 4 and the base 6 and part of the inside of the insertion holes 26-1, 26-2, and after filling, the resin solidifies to form the resin layers 8-1, 8-2. The resin forming the resin layers 8-1, 8-2 needs only to have an affinity for the base 6, the exterior case 12, and the sealing member 16, and to have gas barrier properties, and should have a linear expansion coefficient of aluminum (approximately 23×10 -6 It is preferable that the resin has a linear expansion coefficient close to that of the resin of the present invention (e.g., 270°C / °F), has a small amount of shrinkage during curing, and is non-hygroscopic. The resin may be, for example, an epoxy resin, an alkyd resin, a urethane resin, a thermosetting resin, or an ultraviolet curing resin. The epoxy resin may be, for example, a two-liquid mixed epoxy resin using an acid anhydride, or a one-liquid epoxy resin. In a solidified state, the resin layers 8-1 and 8-2 formed from such materials have heat resistance to the heat treatment temperature (e.g., 270°C) used when mounting the capacitor 2 on a wiring board.

[0053] The fixing resin 10 is a solidified resin, and has, for example, the same heat resistance as the resin layers 8-1 and 8-2. The fixing resin 10 is disposed between both side surfaces of the exposed terminal portion 22 of the terminal leads 18-1 and 18-2 and the edges of the guide grooves 28-1 and 28-2, and is formed integrally with the resin layer 8-2. The fixing resin 10 fills the gap between both side surfaces of the exposed terminal portion 22 and the edges of the guide grooves 28-1 and 28-2. Therefore, the fixing resin 10 strengthens the bonding force of the exposed terminal portion 22 to the base 6, and enhances the unity of the exposed terminal portion 22 and the base 6. The resin in the insertion hole portions 26-1 and 26-2 reaches, for example, the guide grooves 28-1 and 28-2, and flows along the exposed terminal portion 22 in the guide grooves 28-1 and 28-2 to form the fixing resin 10. That is, the fixing resin 10 is formed during the formation process of the resin layers 8-1 and 8-2, and the manufacturing load is suppressed. However, resin may be added from the board mounting surface of the base 6 to form the fixing resin 10. If the fixing resin 10 is formed by resin coming from inside the insertion holes 26-1, 26-2 in some of the manufactured capacitors 2, the addition of resin from the board mounting surface can be suppressed, and the manufacturing load can be suppressed. The resin forming the fixing resin 10 may be the same as or different from the resin forming the resin layers 8-1, 8-2.

[0054] As shown in FIG. 1B, the fixing resin 10 may fill a part (e.g., half) of the gap between both side surfaces of the exposed terminal portion 22 and the edges of the guide grooves 28-1 and 28-2, or may fill the entire gap. The arrangement range of the fixing resin 10 may be wider or narrower than half of the gap. The wider the arrangement range of the fixing resin 10, the higher the integration of the exposed terminal portion 22 and the base 6. The surface of the fixing resin 10 is preferably at the same position as a plane including the top surface of the support portion 46 or a plane including the exposed surface of the exposed terminal portion 22, or on the base 6 side of these planes. It is more preferable that the surface of the fixing resin 10 is at the same position as the board mounting surface of the base 6, or on the inner side of the base 6 than these planes. In other words, it is more preferable that the surface of the fixing resin 10 is inside the guide grooves 28-1 and 28-2. Since the fixing resin 10 does not protrude beyond these planes or the board mounting surface, the fixing resin 10 does not interfere with the board mounting of the capacitor 2.

[0055] 2A, the central axes C1 of the terminal leads 18-1, 18-2 in the insertion holes 26-1, 26-2 may be disposed closer to the outer edge of the base 6 than the centers C2 of the openings of the insertion holes 26-1, 26-2 on the board mounting surface side (i.e., the openings of the insertion holes on the board mounting surface side). In other words, the distance between the terminal leads 18-1, 18-2 and the inner surfaces of the insertion holes 26-1, 26-2 (hereinafter referred to as the "separation distance") on the outer edge side of the base 6 may be narrower than the separation distance on the center side of the base 6. Due to the difference in the separation distance, for example, the action of capillary action becomes larger on the outer edge side than on the center side, and low-viscosity resin can move on the outer edge side to the opening side of the insertion holes 26-1, 26-2 (i.e., the board mounting surface side). Further, a low-viscosity resin may flow into the guide grooves 28-1, 28-2 through the openings of the insertion holes 26-1, 26-2. Therefore, as shown in A of FIG. 2, a level difference may occur on the surface of the resin layer 8-2, and the bent portion 20 may be exposed from the resin layer 8-2 on the central side. The gaps between the terminal leads 18-1, 18-2 and the insertion holes 26-1, 26-2 are filled with resin on the outer edge side, and the resin layer 8-2 is connected to the fixing resin 10.

[0056] As shown in FIG. 2B, the insertion holes 26-1 and 26-2 may have a step 56. The step 56 makes the opening distance D1 of the insertion holes 26-1 and 26-2 on the board mounting surface side larger than the opening distance D2 on the capacitor body 4 side. The step 56 is formed on the inner side of the insertion holes 26-1 and 26-2, and includes a step 56-1 arranged on the center side of the capacitor 2 and a step 56-2 arranged on the side of the capacitor 2. The width W1 of the step 56-1 is wider than the width W2 of the step 56-2. The difference between the widths W1 and W2 causes a difference in the action of capillary action. In addition, the step 56 keeps the opening distance D2 small, and the gap between the terminal leads 18-1 and 18-2 and the insertion holes 26-1 and 26-2 on the capacitor body 4 side is small. Therefore, the movable range of terminal leads 18-1, 18-2 is restricted by sealing material 16. In addition, the amount of resin that moves to the outside of base 6 (substrate mounting surface) through insertion holes 26-1, 26-2 can be adjusted by the widths W1, W2 of steps 56-1, 56-2.

[0057] On the capacitor body 4 side of the step 56, the cross section of the insertion holes 26-1, 26-2 (hereinafter referred to as the "body side cross section") has, for example, a rectangular shape with rounded corners, as shown in A of Fig. 3. On the board mounting surface side of the step 56, the cross section of the insertion holes 26-1, 26-2 (hereinafter referred to as the "mounting surface side cross section") has, for example, a shape formed by two partially overlapping circles, as shown in B of Fig. 3. The two circles have different sizes, and the larger circle includes the body side cross section. Of the two circles, the smaller circle is positioned closer to the center of the capacitor 2 than the larger circle. [Capacitor manufacturing process]

[0058] The capacitor manufacturing process is an example of a capacitor manufacturing method of the present disclosure, and this manufacturing process includes a step of forming the capacitor body 4, a step of forming the base 6, a step of attaching the base 6, a step of molding the terminal leads 18-1, 18-2, a step of injecting resin, and a step of hardening the resin and forming the fixing resin 10.

[0059] In the process of forming capacitor body 4, first, an anode foil connected to terminal lead 18-1 and a cathode foil connected to terminal lead 18-2 are wound with a separator interposed between them to form capacitor element 14. Capacitor element 14 is impregnated with an electrolyte and this capacitor element 14 is then sealed in exterior case 12, after which sealing member 16 is attached to the opening of exterior case 12, and capacitor body 4 is formed. Exterior case 12 is made of, for example, aluminum.

[0060] In the process of forming base 6, base 6 is formed into the shape described above from insulating synthetic resin. Note that, in the first embodiment, an electrolytic capacitor is formed by impregnating capacitor element 14 with an electrolytic solution, but this is not limiting, and a solid electrolytic capacitor may be formed by using capacitor element 14 in which a solid electrolyte layer is formed by impregnating a conductive polymer, or a hybrid capacitor may be formed by impregnating capacitor element 14 impregnated with a conductive polymer with an electrolytic solution.

[0061] In the mounting step of the base 6, the terminal leads 18-1, 18-2 of the capacitor body 4 are inserted through the insertion holes 26-1, 26-2 of the base 6. Then, the base 6 is moved and mounted on the sealing member 16 side of the capacitor body 4. In this mounting step, the protrusion 30 of the base 6 is disposed on the sealing member 16 side.

[0062] In the molding process of the terminal leads 18-1, 18-2, the terminal leads 18-1, 18-2 are bent along the guide grooves 28-1, 28-2 of the base 6, and the exposed terminal portions 22 of the terminal leads 18-1, 18-2 are placed in the guide grooves 28-1, 28-2. Through this molding process, the base 6 is fixed to the capacitor body 4, as shown in A of FIG.

[0063] In the resin injection process, as shown in B of FIG. 4, the movement of the capacitor body 4 is restricted, and a resin discharger 58 of a resin discharge device such as a dispenser is pressed against the resin injection hole 36 of the base 6. Then, the resin is injected from the resin injection hole 36 into the gap SP (A of FIG. 4). The liquid resin injected from the resin injection hole 36 fills the gap SP between the capacitor body 4 and the base 6. The resin spreads around the resin injection hole 36, and flows through the gap between the protrusion 30 and the support protrusion 34 or through the groove 52 toward the through hole 38, and spreads around the through hole 38 and the shielding part 40. In addition, a part of the resin flows to the outside of the capacitor body 4 through the outside of the end of the support protrusion 34. In addition, a part of the resin may flow through the groove 54 into the inside of the insertion hole parts 26-1 and 26-2.

[0064] In the process of curing the resin and forming the fixing resin 10, the injected resin is heated, for example. The viscosity of the heated resin decreases before curing. Therefore, a part of the resin with reduced viscosity passes through the insertion holes 26-1, 26-2 and moves to the guide grooves 28-1, 28-2 by capillary action, as shown in FIG. 4C. The resin then cures, and the resin layers 8-1, 8-2 and the fixing resin 10 are integrally formed.

[0065] After the steps of curing the resin and forming the fixing resin 10, the capacitor 2 may be inspected. If the resin layer 8-2 or the fixing resin 10 is insufficient for the manufacturing standard, resin may be added, for example, from the board mounting surface side of the base 6, and the added resin may then be cured. Such a resin adding step is only performed on capacitors for which the resin layer 8-2 or the fixing resin 10 is insufficient for the manufacturing standard. Therefore, the manufacturing load of the capacitor is suppressed overall. EXAMPLES

[0066] A of Fig. 5, A of Fig. 6, and A of Fig. 7 are cross-sectional views showing examples of the capacitors according to Examples 1, 2, and 3, respectively, and B of Fig. 5, B of Fig. 6, and B of Fig. 7 are bottom views of the capacitors, respectively. The configurations shown in Fig. 5, Fig. 6, and Fig. 7 are merely examples, and the technology of the present disclosure is not limited to such configurations. In Fig. 5, Fig. 6, and Fig. 7, the same parts as those in Fig. 1 to Fig. 3 are denoted by the same reference numerals.

[0067] Capacitor 62 of Example 1, capacitor 72 of Example 2, and capacitor 82 of Example 3 are the same as capacitor 2 of the first embodiment, except for resin layer 8-2 and fixing resin 10. Resin layer 8-2 and fixing resin 10 of capacitors 62, 72, and 82 are different from resin layer 8-2 and fixing resin 10 of capacitor 2, as described below.

[0068] In the capacitor 62, the resin layer 8-2 is formed inside the insertion hole 26-1 except for the opening of the insertion hole 26-1, and is formed throughout the interior of the insertion hole 26-2 (excluding the portions where the terminal leads 18-1 and 18-2 are arranged). The gap between the terminal lead 18-2 and the insertion hole 26-2 is entirely filled with resin on both the outer edge side and the center side, and the resin layer 8-2 covers a part of the bent portion 20 of the terminal lead 18-2 on the center side. The bent portion 20 of the terminal lead 18-1 is exposed. The fixing resin 10 fills half of the gap between both side surfaces of the exposed terminal portion 22 of the terminal lead 18-2 and the edge of the guide groove 28-2, and is formed integrally with the resin layer 8-2 inside the insertion hole 26-2. Air is arranged between both side surfaces of the exposed terminal portion 22 of the terminal lead 18-1 and the edge of the guide groove 28-1. That is, the fixing resin 10 is formed only in the guide groove 28-2.

[0069] In the capacitor 72, the resin layer 8-2 is formed over the entire inside of the insertion hole portions 26-1, 26-2 (excluding the portions where the terminal leads 18-1, 18-2 are arranged). The gaps between the terminal leads 18-1, 18-2 and the insertion hole portions 26-1, 26-2 are entirely filled with resin on both the outer edge side and the center side, and the resin layer 8-2 covers a part of the bent portion 20 of the terminal leads 18-1, 18-2 on the center side. The fixing resin 10 fills half of the gaps between both side surfaces of the exposed terminal portion 22 of the terminal leads 18-1, 18-2 and the edges of the guide grooves 28-1, 28-2. The fixing resin 10 in the guide groove 28-1 is formed integrally with the resin layer 8-2 in the insertion hole portion 26-1, and the fixing resin 10 in the guide groove 28-2 is formed integrally with the resin layer 8-2 in the insertion hole portion 26-2. That is, the fixing resin 10 is formed in both the guide grooves 28-1 and 28-2.

[0070] In the capacitor 82, the resin layer 8-2 is formed over the entire inside of the insertion hole portions 26-1, 26-2 (excluding the portions where the terminal leads 18-1, 18-2 are arranged). The gaps between the terminal leads 18-1, 18-2 and the insertion hole portions 26-1, 26-2 are entirely filled with resin on both the outer edge side and the center side, and on the center side, the resin layer 8-2 covers a part of the bent portion 20 of the terminal leads 18-1, 18-2. The fixing resin 10 fills the entire gaps between both side surfaces of the exposed terminal portion 22 of the terminal leads 18-1, 18-2 and the edges of the guide grooves 28-1, 28-2. The fixing resin 10 in the guide groove 28-1 is formed integrally with the resin layer 8-2 in the insertion hole portion 26-1, and the fixing resin 10 in the guide groove 28-2 is formed integrally with the resin layer 8-2 in the insertion hole portion 26-2. That is, the fixing resin 10 is formed in both the guide grooves 28-1 and 28-2.

[0071] The capacitor according to Example 4 is a capacitor similar to the capacitor 2 according to the first embodiment (for convenience, the capacitor according to Example 4 is also referred to as "capacitor 2"). In the capacitor 2 according to Example 4, as shown in FIG. 1A and FIG. 1B, the surface of the resin layer 8-2 has a level difference, and the bent portions 20 of the terminal leads 18-1 and 18-2 are exposed from the resin layer 8-2 at the center side. The fixing resin 10 fills half of the gap between both side surfaces of the exposed terminal portions 22 of the terminal leads 18-1 and 18-2 and the edges of the guide grooves 28-1 and 28-2. The fixing resin 10 in the guide groove 28-1 is formed integrally with the resin layer 8-2 in the insertion hole portion 26-1, and the fixing resin 10 in the guide groove 28-2 is formed integrally with the resin layer 8-2 in the insertion hole portion 26-2. That is, the fixing resin 10 is formed in both the guide grooves 28-1 and 28-2.

[0072] The adhesion of the capacitors 2, 62, 72, and 82 according to the examples was evaluated by an adhesion test. In the adhesion test, a pressing force was applied along the center line L (B in FIG. 1) to the capacitors 2, 62, 72, and 82 soldered to the board. The pressing force was determined in accordance with "8.5.3 Test U: Terminal strength test method" of the Japanese Industrial Standards JIS C60068-2-21 "Environmental test methods - Electrical and electronic - Part 2-21: Tests - Test U: Terminal strength test method". e3 The pressing tool described in the test method for "Adhesion (shear strength) test" was used, as shown in Figure 11 of this Japanese Industrial Standard. The pressing tool was moved at a speed of 100 mm / min, and the load due to the pressing force, the displacement of capacitors 2, 62, 72, 82, and the load immediately before capacitors 2, 62, 72, 82 were separated from the substrate (hereinafter referred to as "adhesion strength").

[0073] Fig. 8A is a graph showing the relationship between load and displacement of capacitor 62 according to Example 1, Fig. 8B is a graph showing the relationship between load and displacement of capacitor 72 according to Example 2, and Fig. 8C is a graph showing the relationship between load and displacement of capacitor 2 according to Example 4. Fig. 8A shows the result of one measurement, Fig. 8B shows the result of three measurements, and Fig. 8C shows the result of three measurements.

[0074] The adhesion strengths of the capacitors 2, 62, 72, and 82 are as follows. Note that the adhesion strengths shown below are the average values ​​of three measurements. (Adhesive strength) Example 1: 129.1 [N (Newton)] Example 2: 195.4 [N] Example 3: 213.4 [N] Example 4: 188.8 [N]

[0075] The capacitors according to Comparative Examples 1 and 2 were evaluated in the same manner as the capacitors 2, 62, 72, and 82. The capacitor according to Comparative Example 1 includes a resin layer 8-2 formed inside the insertion holes 26-1 and 26-2 excluding the openings of the insertion holes 26-1 and 26-2 and the portions where the terminal leads 18-1 and 18-2 are disposed, but does not include the fixing resin 10. The capacitor according to Comparative Example 2 is not injected with resin, and does not include the resin layers 8-1 and 8-2 and the fixing resin 10.

[0076] Fig. 9A is a graph showing the relationship between load and displacement of the capacitor according to Comparative Example 1, and Fig. 9B is a graph showing the relationship between load and displacement of the capacitor according to Comparative Example 2. Fig. 9A shows the results of three measurements, and Fig. 9B shows the results of three measurements.

[0077] The adhesion strengths of the capacitors according to Comparative Examples 1 and 2 are as follows. Note that the adhesion strengths shown below are the average values ​​of three measurement results. (Adhesive strength) Comparative Example 1: 118.4 [N] Comparative Example 2: 113.7 [N]

[0078] From the measurement results of the capacitors of Comparative Example 1 and Comparative Example 2, it is found that the adhesive strength is increased by the arrangement of the resin layers 8-1 and 8-2. Also, from the measurement results of the capacitors 2, 62, 72, and 82 and the capacitor of Comparative Example 1, it is found that the adhesive strength is increased by the arrangement of the fixing resin 10. The capacitors 2, 62, 72, and 82 can have a higher adhesive strength than the capacitors of Comparative Examples 1 and 2 by including the resin layers 8-1 and 8-2 and the fixing resin 10. It is found that the adhesive strength of the capacitor is increased even if the fixing resin 10 is arranged only on one of the guide grooves 28-1 and 28-2. The gap between the terminal leads 18-1 and 18-2 and the edges of the guide grooves 28-1 and 28-2 is filled with the fixing resin 10, and the fixing resin 10 is integrated with at least the resin layer 8-2, which is considered to increase the degree of integration between the capacitor body 4 and the base 6, thereby improving the adhesive strength.

[0079] In order to strengthen the connection between the capacitor and the board, it is thought that it is better to leave the sides of the terminal leads 18-1, 18-2 exposed so that solder will adhere to them when mounted on the board. However, the above measurement results show that the adhesive strength is improved when the sides of the terminal leads 18-1, 18-2 are fixed to the base 6 with resin rather than being connected to the board with solder.

[0080] The measurement results of the capacitors 2, 62, 72, and 82 show that the wider the range of arrangement of the fixing resin 10, the higher the fixing strength. The measurement results of the capacitors 2 and 72 of Examples 2 and 4 show that the fixing strength is increased by arranging the resin also near the bent portions 20 of the terminal leads 18-1 and 18-2. On the other hand, in the capacitor 2 of Example 4, the bent portions 20 of the terminal leads 18-1 and 18-2 are exposed, so that, for example, welding at the bent portions 20 is possible, which has the effect of reducing the electrical resistance of the connection between the terminals and the board.

[0081] 8 and 9, it can be seen that the displacement with respect to an increase in load is smaller in the capacitors 2, 62, 72, and 82 (i.e., the slope of the measured values ​​shown in each graph is steeper) than in the capacitors of Comparative Examples 1 and 2. It is believed that the increased degree of integration between the capacitor body 4 and the base 6 allows the entire capacitor 2, 62, 72, and 82 to bear the load due to the pressing force, which increases the fixing strength and makes the capacitors 2, 62, 72, and 82 less likely to separate from the substrate.

[0082] Furthermore, when exposed terminal portions 22 of terminal leads 18-1, 18-2 are fixed to base 6, the stress acting on exposed terminal portions 22 is dispersed according to the degree of fixation, making capacitors 2, 62, 72, 82 less likely to separate from the board.

[0083] According to the first embodiment and example, the following actions and effects can be obtained.

[0084] (1) The integrity of capacitor body 4 and base 6 can be improved, and the bonding strength of exposed terminal portion 22 to base 6 can be strengthened. This can increase the bonding strength of capacitors 2, 62, 72, 82 to a wiring board, for example.

[0085] (2) Since the fixing resin 10 is formed integrally with the resin layers 8-1 and 8-2, an increase in the manufacturing load of the capacitors 2, 62, 72, and 82 can be suppressed.

[0086] (3) Because the fixing resin 10 is hardened by the resin hardening process, there is little change in the connection portions of the capacitors 2, 62, 72, 82 to the wiring board during the process of connecting the capacitors 2, 62, 72, 82, such as the reflow process. Therefore, when the manufacture of the capacitors 2, 62, 72, 82 is completed, it is possible to confirm the approximate final state of the capacitors 2, 62, 72, 82. Compared to capacitors that include sandwiched solder, the capacitors 2, 62, 72, 82 that change little after manufacture are beneficial, for example, from the standpoint of quality assurance. Second embodiment

[0087] Fig. 10A is a cross-sectional view showing an example of a capacitor according to the second embodiment, and Fig. 10B is a partial bottom view of the capacitor. In Fig. 10A, a part of the capacitor body is omitted. Fig. 11 is a bottom view of the base. In Figs. 10 and 11, the same parts as in Figs. 1 to 3 are given the same reference numerals.

[0088] Capacitor 102 is an example of an electronic component, such as an electrolytic capacitor or an electric double layer capacitor. Capacitor 102 includes a capacitor body 4, a base 106, resin layers 8-1 and 8-3, and a fixing resin 10. Base 106 is placed on capacitor body 4, and resin layer 8-1 is disposed in the gap between base 106 and capacitor body 4. Capacitor 102 can be mounted on a wiring board such as a circuit board. Capacitor body 4, resin layer 8-1, and fixing resin 10 are the same as those in the first embodiment, and description thereof will be omitted.

[0089] The seat 106 is disposed on the sealing member 16 side of the capacitor body 4. The seat 106 is formed of an insulating plate such as the insulating synthetic resin described above, similar to the seat 6 of the first embodiment. The seat 106 includes guide grooves 28-1 and 28-2, a peripheral wall 32, a resin injection hole 36, a through hole 38, step portions 42 and 44, and a support portion 46, similar to the seat 6 of the first embodiment, and also includes a support protrusion and a shielding portion (not shown). The guide grooves 28-1 and 28-2, the peripheral wall 32, the resin injection hole 36, the through hole 38, the step portions 42 and 44, and the support portion 46 are similar to those of the first embodiment, and the support protrusion and the shielding portion are similar to the support protrusion 34 and the shielding portion 40 of the first embodiment, and therefore the description thereof will be omitted. The base 106 further includes second insertion hole portions 126-1 and 126-2 (hereinafter referred to as “insertion hole portions 126-1 and 126-2”), a protrusion 130, and a connection groove 160.

[0090] The through-holes 126-1 and 126-2 are holes formed at positions corresponding to the terminal leads 18-1 and 18-2. The pair of terminal leads 18-1 and 18-2 protruding from the capacitor body 4 penetrate the pair of through-holes 126-1 and 126-2 formed in the base 106 and are drawn out to the outer surface side of the base 106, that is, the board mounting surface side of the base 106. The through-holes 126-1 and 126-2, together with the through-holes 24-1 and 24-2, form through-holes for passing the terminal leads 18-1 and 18-2. The through-holes 126-1 and 126-2 may have a step portion 56 as shown in FIG. 10A and FIG. 11. The step portion 56 is the same as the step portion 56 in the first embodiment, and the description thereof will be omitted. The shape of the through-holes 126-1 and 126-2 is circular as shown in FIG. 11. However, the insertion holes 126-1 and 126-2 may have the same shape as the insertion holes 26-1 and 26-2 of the first embodiment.

[0091] The protrusion 130 is similar to the protrusion 30 of the first embodiment, except that a connection groove 160 is formed on the rear surface of the protrusion 130, i.e., the outer surface or board mounting surface of the base 106, and therefore a description thereof will be omitted.

[0092] The connection groove 160 is disposed between the insertion hole portions 126-1 and 126-2 on the outer surface or board mounting surface of the base 106. The connection groove 160 connects to the insertion hole portions 126-1 and 126-2. Therefore, the connection groove 160 connects the insertion hole portion 126-1 and the insertion hole portion 126-2, and the insertion hole portion 126-1 is connected to the insertion hole portion 126-2 via the connection groove 160. The bottom of the connection groove 160 is disposed on the same plane as the step portions 56 of the insertion hole portions 126-1 and 126-2, particularly the step portion 56-1. Therefore, there is no step between the connection groove 160 and the step portion 56-1, and the connection groove 160 and the step portions 56 of the insertion hole portions 126-1 and 126-2 are integrated.

[0093] The connection groove 160 is, for example, line-symmetrical with respect to the center line L (B in FIG. 1, B in FIG. 10) described in the first embodiment, and has a narrow width at the center and a wide width at the end portions on the side of the insertion holes 126-1 and 126-2. Therefore, the connection groove 160 can flow more liquid resin at the end portions than at the center portion, and the connection groove 160 can guide the liquid resin farther from the end portions. In addition, since the width of the connection groove 160 is narrow at the center portion, the connection groove 160 is prevented from interfering with the arrangement of the resin injection hole 36 and the through hole 38, and the connection groove 160 can be prevented from connecting to the step portions 42, 44 of the resin injection hole 36 and the through hole 38.

[0094] It is preferable that the bottom and side walls of the connection groove 160 are flat. The flat bottom and side walls can suppress turbulence of the flowing resin, and can suppress, for example, the formation of gaps between the bottom and side walls of the connection groove 160 and the resin.

[0095] The resin layer 8-3 is provided inside the insertion holes 126-1, 126-2 and the connection groove 160. The resin layer 8-3 fills the gap between the inner surfaces of the insertion holes 126-1, 126-2 and the terminal leads 18-1, 18-2, and bonds with the fixing resin 10. This improves the sealing performance and reduces the amount of gas passing through the insertion holes 126-1, 126-2. The resin layer 8-3 strengthens the bonding force of the base 106 to the terminal leads 18-1, 18-2, and improves the unity of the capacitor body 4 and the base 106. In addition, the resin layer 8-3 is disposed inside the connection groove 160, so that the contact area of ​​the resin layer 8-3 with the base 106 is increased. 10A, in a cross section taken through the insertion holes 126-1, 126-2 and the protrusion 130, the resin layer 8-3 comes into contact with the protrusion 130 in three directions, and the resin layer 8-3 engages with the protrusion 130. Therefore, the resin layer 8-3 strengthens the bonding force of the base 106 to the resin layer 8-3 and further the bonding force of the base 106 to the terminal leads 18-1, 18-2, thereby improving the unity of the capacitor body 4, the base 106, and the resin layers 8-1, 8-3. The resin forming the resin layer 8-3 is the same as the resin forming the resin layers 8-1, 8-2 in the first embodiment, and a description thereof will be omitted.

[0096] The resin injected from the resin injection hole 36 reaches, for example, the through-holes 126-1 and 126-2 and the connection groove 160, and the resin that has passed through the through-hole 126-1 is joined to the resin that has passed through the through-hole 126-2 at the connection groove 160. Therefore, the resin layer 8-3 in the through-hole 126-1, the resin layer 8-3 in the through-hole 126-2, and the resin layer 8-3 in the connection groove 160 are integrated. In addition, the resin layer 8-3 is formed during the formation process of the resin layer 8-1, and the manufacturing load is suppressed. However, the resin layer 8-3 may be formed by adding resin from the board mounting surface of the base 106. If the resin layer 8-3 is formed by the injected resin in some of the manufactured capacitors 102, the addition of resin from the board mounting surface can be suppressed, and the manufacturing load can be suppressed. [Capacitor manufacturing process]

[0097] The capacitor manufacturing process is an example of a capacitor manufacturing method of the present disclosure, and includes the steps of forming the capacitor body 4, forming the pedestal 106, attaching the pedestal 106, molding the terminal leads 18-1 and 18-2, injecting the resin, and hardening the resin and forming the fixing resin 10. The steps of forming the capacitor body 4, attaching the pedestal 106, molding the terminal leads 18-1 and 18-2, and injecting the resin are similar to those in the first embodiment, and therefore description thereof will be omitted.

[0098] In the process of forming the base 106, the base 106 is formed from insulating synthetic resin into the shape described above.

[0099] In the process of curing the resin and forming the fixing resin 10, the injected resin is heated, for example. The viscosity of the heated resin decreases before curing. Therefore, as described in the first embodiment, a part of the resin with reduced viscosity passes through the insertion holes 126-1 and 126-2 and moves to the guide grooves 28-1 and 28-2 by capillary action. In addition, a part of the resin that passed through the insertion holes 126-1 and 126-2 flows into the connection groove 160, and the resin that passed through the insertion hole 126-1 and the resin that passed through the insertion hole 126-2 are joined in the connection groove 160. The resin is then cured, and the resin layers 8-1 and 8-3 and the fixing resin 10 are integrally formed.

[0100] After the steps of curing the resin and forming the fixing resin 10, the capacitor 102 may be inspected. If the resin layer 8-3 or the fixing resin 10 is insufficient for the manufacturing standard, resin may be added, for example, from the board mounting surface side of the base 106, and the added resin may then be cured. Such a resin adding step is only performed on capacitors for which the resin layer 8-3 or the fixing resin 10 is insufficient for the manufacturing standard. Therefore, the manufacturing load of the capacitor is suppressed overall.

[0101] As described in the first embodiment, capacitor 102 may be a solid electrolytic capacitor using capacitor element 14 in which a solid electrolyte layer is formed by impregnating a conductive polymer, or may be a hybrid capacitor in which capacitor element 14 impregnated with a conductive polymer is impregnated with an electrolyte.

[0102] According to the second embodiment, the following actions and effects can be obtained.

[0103] (1) The same functions and effects as those of the capacitor 2 of the first embodiment can be obtained.

[0104] (2) Since the base 106 has the connection groove 160, a part of the resin that has passed through the insertion holes 126-1, 126-2 can flow into the connection groove 160. Therefore, a space for holding the resin can be secured near the bent portions 20 of the terminal leads 18-1, 18-2. Since the bent portions 20 of the terminal leads 18-1, 18-2 are exposed, as described in the fourth embodiment, for example, welding can be performed at the bent portions 20, which has the effect of reducing the electrical resistance of the connection between the terminals and the substrate.

[0105] (3) The contact area of ​​resin layer 8-3 with base 106 increases, and resin layer 8-3 engages with protrusion 130. As a result, the bonding force between resin layer 8-3 and base 106 increases in the central portion of capacitor 102, and the integrity of capacitor body 4, base 106, resin layers 8-1 and 8-3, and fixing resin 10 is improved.

[0106] Regarding the above-mentioned embodiment and example, features, advantages, modifications, etc. will be listed below.

[0107] (1) In the first embodiment and examples, the fixing resin 10 may be disposed in at least one of the guide grooves 28-1, 28-2. The disposed fixing resin 10 may be disposed in a part of the gap between the terminal leads 18-1, 18-2 and the edges of the guide grooves 28-1, 28-2, and the arrangement of the fixing resin 10 is not limited to half or the entire gap as described in the first embodiment and examples. The arrangement range of the fixing resin 10 may be wider or narrower than half of the gap. The wider the arrangement range of the fixing resin 10, the higher the integration of the exposed terminal portion 22 and the base 6. In the second embodiment, the arrangement position of the fixing resin 10 may be modified in the same manner as the fixing resin 10 in the first embodiment and examples.

[0108] (2) In the above embodiment and example, the guide grooves 28-1, 28-2 have a constant width. However, the guide grooves 28-1, 28-2 may have a non-uniform width. The guide grooves 28-1, 28-2 may be wider on the insertion hole side and narrower on the outer edge side of the base 6, 106, for example. By widening the width on the insertion hole side, the resistance to the passage of the resin toward the outer edge side is suppressed, making it easier for the resin to pass toward the edge side.

[0109] (3) In the above first embodiment and example, the bent portion 20 is exposed, or the resin layer 8-2 covers a part of the bent portion 20. However, the bent portion 20 may be embedded in the resin layer 8-2. When the bent portion 20 is embedded in the resin layer 8-2, the terminal leads 18-1, 18-2 can be fixed to the base 6 more firmly.

[0110] (4) The capacitors 2, 62, 72, and 82 of the first embodiment and examples may have a protrusion on the sealing material side instead of the protrusion 30, and the capacitor 102 of the second embodiment may have a protrusion on the sealing material side instead of the protrusion 130. In this case, the capacitor includes a base that does not have the protrusions 30 and 130 and a sealing material that has a protrusion, and an insertion hole is formed by the first insertion hole portion of the sealing material and the second insertion hole portion of the base, and the resin layer 8-2 or the resin layer 8-3 is disposed in a part of the inside of this insertion hole. Such a capacitor also has the action or effect already described in the embodiments and examples.

[0111] (5) In the first embodiment and the example, the through-holes 26-1 and 26-2 have the step 56 so that the opening distance D1 of the through-holes 26-1 and 26-2 on the board mounting surface side is larger than the opening distance D2 on the capacitor body 4 side. However, the shape of the through-hole is not limited to the shape already described in the first embodiment. For example, the through-hole may have an inclined surface instead of the step 56, and the opening distance D1 of the through-holes 26-1 and 26-2 on the board mounting surface side may be larger than the opening distance D2 on the capacitor body 4 side. Also, the through-hole may not have the step 56, may have a uniform opening distance, or may have a plurality of steps formed in a staircase shape. Also, in the second embodiment, the through-holes 126-1 and 126-2 have the step 56. However, for example, the through-hole may have an inclined surface instead of the step 56 as described. 12, the guide grooves 28-1, 28-2 and the connecting groove 160 may be directly connected to the insertion hole portions 126-1, 126-2 that do not include the step portion 56. As shown in FIG.

[0112] (6) In the above first embodiment and example, the width W1 of the step portion 56-1 is wider than the width W2 of the step portion 56-2, and therefore the central axes C1 of the terminal leads 18-1, 18-2 are disposed closer to the outer edge of the base 6 than the center C2 of the opening of the insertion hole on the board mounting surface side. However, the width W1 may be the same as the width W2, or the width W1 may be narrower than the width W2. Since the center-to-center distance of the terminal leads 18-1, 18-2 is greater than the center-to-center distance of the two insertion holes, the central axes C1 of the terminal leads 18-1, 18-2 may be disposed closer to the outer edge of the base 6 than the center C2 of the opening of the insertion hole on the board mounting surface side.

[0113] (7) The materials used to form the base 6, 106, the resin layers 8-1, 8-2, 8-3, the fixing resin 10, the exterior case 12 and the sealing member 16 are not limited to those mentioned above, and may be changed as appropriate.

[0114] (8) The protrusions 30 and 130 may be modified as appropriate as long as they surround the insertion holes 26-1, 26-2, 126-1, and 126-2, without being limited to the above-described shapes. For example, the base 6 and 106 may have two protrusions, and these two protrusions may surround the insertion holes 26-1 and 126-1, and the insertion holes 26-2 and 126-2, respectively. The sealing member 16 may have two protrusions, and these two protrusions may surround the insertion holes 26-1 and 126-1, and the insertion holes 26-2 and 126-2, respectively. The grooves 52 and 54 may be provided as necessary.

[0115] (9) In the above embodiment, the resin injection hole 36 is formed in the base 6, 106, and the base 6, 106 is installed on the capacitor body 4, and then the resin is injected to form the resin layers 8-1, 8-2, 8-3, and the fixing resin 10. However, this may be modified as appropriate. The resin may be applied to the capacitor body 4 or the base 6, 106, and then the base 6, 106 is attached to the sealing member 16 side of the capacitor body 4, and the resin may be spread between the capacitor body 4 and the base 6, 106 to fill the gap between the capacitor body 4 and the base 6, 106. The resin filling the gap between the capacitor body 4 and the base 6, 106 forms the resin layer 8-1. With this configuration, there is no need to provide the resin injection hole 36.

[0116] (10) In the second embodiment, the base 106 includes one connecting groove 160, which is connected to the two insertion holes 126-1 and 126-2. However, the base 106 may include, for example, a first connecting groove and a second connecting groove, and the first connecting groove may be connected to the insertion hole 126-1 and the second connecting groove may be connected to the insertion hole 126-2. In other words, the connecting groove 160 may be divided.

[0117] (11) In the second embodiment described above, resin layer 8-3 is formed over the entire connection groove 160, i.e., over the entire area between the two ends. However, capacitor 102 of the second embodiment only needs to have connection groove 160 into which liquid resin can flow. Resin layer 8-3 may be formed only partially in connection groove 160, or may not be formed in connection groove 160.

[0118] (12) The shape of the connecting groove 160, the position of the bottom, the surface condition of the bottom and the sidewalls, etc. may be different from the shape, position, surface condition, etc. described in the second embodiment. For example, the width of the connecting groove 160 may be uniform. The bottom may be located on a plane different from the step 56-1, and the bottom may be inclined so that the central part of the connecting groove 160 is shallower than the ends. The bottom or the sidewalls may have irregularities or steps.

[0119] As explained above, the most preferred embodiment of the present disclosure has been described, however, the technology of the present disclosure is not limited to the above description, and it goes without saying that those skilled in the art can make various modifications and changes based on the gist of the invention described in the claims or disclosed in the specification, and such modifications and changes are naturally included in the scope of the present disclosure. [Industrial Applicability]

[0120] The technology disclosed herein is widely applicable and useful in electronic devices. [Explanation of symbols]

[0121] 2, 62, 72, 82, 102 Capacitors 4. Capacitor body 6, 106 Pedestal 8-1, 8-2 Resin layer 10 Fixing Resin 12 Outer case 14 Capacitor element 16 Sealing member 18-1, 18-2 Terminal leads 20 Bending section 22 Exposed terminal section 24-1, 24-2 First insertion hole portion 26-1, 26-2, 126-1, 126-2 Second insertion hole portion 28-1, 28-2 Guide groove 30, 130 protrusion 32 Peripheral wall 34 Support protrusion 36 Resin injection hole 38 Through hole 40 Shielding part 42, 44, 56, 56-1, 56-2 Stepped section 46 Support part 48 Retreat 50 Flat area 52, 54 Groove 58 Resin discharge section 160 Connection groove

Claims

1. a capacitor body including an outer case, a sealing member having a first insertion hole portion attached to an opening of the outer case, and a terminal lead extending from the first insertion hole portion and having a bent portion and an exposed terminal portion; a base provided on the sealing member side of the capacitor body and having a second insertion hole portion through which the terminal lead is inserted, and a guide groove formed on a board mounting surface and into which the exposed terminal portion is disposed; a resin layer disposed between the base and the sealing member and in a portion of an inside of an insertion hole formed by the first insertion hole portion and the second insertion hole portion; a fixing resin disposed between both side surfaces of the exposed terminal portion of the terminal lead and edges of the guide groove and integrally formed with the resin layer; A capacitor comprising:

2. The capacitor according to claim 1 , wherein the fixing resin is disposed along the exposed terminal portion of the terminal lead.

3. 3. The capacitor according to claim 1, wherein the resin layer covers a part of the bent portion.

4. 4. The capacitor according to claim 1, wherein a surface of the fixing resin is located at the same position as the substrate mounting surface or is located on the inner side of the base relative to the substrate mounting surface.

5. 5. The capacitor according to claim 1, wherein a central axis of the terminal lead is disposed closer to an outer edge of the base than a center of an opening of the insertion hole.

6. The capacitor according to any one of claims 1 to 5, characterized in that the base further has a connection groove on the substrate mounting surface that connects the second insertion hole portion on the anode side and the second insertion hole portion on the cathode side.

7. a step of producing a capacitor body including an outer case, a sealing member having a first insertion hole portion attached to an opening of the outer case, and a terminal lead extending from the first insertion hole portion; A step of producing a base having a second insertion hole portion and a guide groove formed on a substrate mounting surface; a step of placing the base on the sealing material side of the capacitor body and inserting the terminal lead through the second insertion hole portion to be exposed on the board mounting surface side; bending the terminal lead to form a bent portion and an exposed terminal portion on the terminal lead, and arranging the exposed terminal portion in the guide groove; forming a resin layer between the base and the sealing member and in a part of an inside of an insertion hole formed by the first insertion hole portion and the second insertion hole portion; forming a fixing resin integral with the resin layer between both side surfaces of the exposed terminal portion and edges of the guide groove; A method for manufacturing a capacitor comprising:

8. 8. The method for manufacturing a capacitor according to claim 7, wherein in the step of forming the fixing resin, the resin whose viscosity has been reduced by a heat treatment moves from inside the insertion hole to the guide groove to form the fixing resin.

9. 9. The method for manufacturing a capacitor according to claim 8, wherein the heat treatment hardens the resin between the base and the sealing material and the resin inside the insertion hole.

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