Capacitor and method for manufacturing the same

Abstract

The first purpose of the technology disclosed in the present invention is, for example, to suppress the force acting on the resin between the terminal lead and the base due to the capillary phenomenon, and the second purpose is, for example, to suppress the resin between the terminal lead and the base from moving to the outside of the base due to the capillary phenomenon. The capacitor (2) has a capacitor body (4) and a base (6). The capacitor body includes a sealing member (14) installed on the opening portion of the outer casing (10) and terminal leads (16-1, 16-2) led out from the first through-hole portion (17-1, 17-2) of the sealing member. The base is arranged on the sealing member side of the capacitor body and has a second through-hole portion (18-1, 18-2). For example, the base includes a first protrusion (20) surrounding the second through-hole portion, and the second through-hole portion of the base forms a through-hole. The opening distance of the through-hole on the substrate mounting surface side is larger than the opening distance on the capacitor body side.

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 Art

[0002] In order to mount the capacitor on a wiring board such as a circuit substrate, the capacitor has, for example, a base. The terminal lead of the capacitor is led out to the outer side surface (substrate mounting surface) of the base and bent, for example, soldered to the wiring board. The capacitor used for such mounting is called a surface mounted capacitor. The surface mounted capacitor has high versatility, for example, it is used in automobiles.

[0003] When the capacitor is installed outdoors such as in a car, the ambient temperature around the capacitor rises. Therefore, 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 airtightness of the capacitor (for example, Patent Document 1). According to this structure, the heat resistance of the capacitor can be improved. In the capacitor provided with the base, a through insertion hole is formed on the base, and the terminal lead of the capacitor passes through the through insertion hole and is arranged on the outside of the base, that is, the substrate mounting surface side.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 60-245121 Summary of the invention

[0007] Problems to be solved by the invention

[0008] The resin layer is formed, for example, by heating and curing a thermosetting resin. The heated thermosetting resin has the property of reducing viscosity just before curing. The relatively low viscosity thermosetting resin disposed between the terminal lead and the base is subjected to force in the direction toward the outside of the base due to the capillary phenomenon. In addition, when a liquid resin is injected to form a resin layer between the sealing body and the base, the liquid resin that reaches the gap between the terminal lead and the base is subjected to force in the direction toward the outside of the base due to the capillary phenomenon. When the resin subjected to this force moves toward the outside of the base, there is a possibility that the resin adheres to the periphery of the terminal lead disposed on the outside of the base and hinders the welding of the terminal lead.

[0009] Patent Document 1 does not disclose or teach the above-mentioned problem, and the structure disclosed in Patent Document 1 cannot solve the above-mentioned problem.

[0010] Therefore, a first object of the technology disclosed in the present invention is to suppress the force acting on the resin between the terminal lead and the base due to, for example, a capillary phenomenon.

[0011] In addition, a second object of the technology disclosed in the present invention is to suppress, for example, the resin between the terminal lead and the base from moving to the outside of the base due to a capillary phenomenon.

[0012] Means for solving problems

[0013] According to a first aspect of the present disclosure, a capacitor has a capacitor body, a base, and a resin layer. The capacitor body includes an outer casing, a sealing member having a first insertion hole and mounted on an opening of the outer casing, and a terminal lead led out of the first insertion hole. The base is provided on the sealing member side of the capacitor body, and has a second insertion hole for the terminal lead to be inserted and exposed to the substrate mounting surface side. The resin layer is arranged between the base and the sealing member. The base includes a first protrusion surrounding the second insertion hole, and the second insertion hole of the base forms a through-insertion hole, or the sealing member includes a second protrusion surrounding the first insertion hole and in contact with the base, and the second insertion hole of the base and the first insertion hole surrounded by the second protrusion form a through-insertion hole. The resin layer is adjacent to the first protrusion or the second protrusion. The opening distance of the through-insertion hole on the substrate mounting surface side is larger than the opening distance on the capacitor body side.

[0014] In the above capacitor, the insertion hole may have a step portion or an inclined surface on an inner side surface of the insertion hole.

[0015] In the above capacitor, a difference in opening distances on the outer side of the terminal lead may be smaller than a difference in opening distances on the central side of the terminal lead.

[0016] According to a second aspect of the present disclosure, a method for manufacturing a capacitor includes the following steps: manufacturing a capacitor body including an outer case, a sealing member having a first insertion hole and mounted on an opening of the outer case, and a terminal lead extending from the first insertion hole; manufacturing a base having a second insertion hole; and arranging the base on the sealing member side of the capacitor body, and allowing the terminal lead to be inserted through the second insertion hole and exposed to the substrate mounting surface side. In manufacturing the base, a first protrusion surrounding the second insertion hole is formed on the base, and the second insertion hole of the base forms a through-hole, or, in manufacturing the capacitor body, a second protrusion surrounding the first insertion hole and having a height for contacting the base is formed on the sealing member, and the second insertion hole of the base and the first insertion hole surrounded by the second protrusion form a through-hole. The opening distance of the through-hole on the substrate mounting surface side is larger than the opening distance on the capacitor body side.

[0017] The method for manufacturing the capacitor may further include the step of forming a resin layer disposed between the base and the sealing member and adjacent to the first protrusion or the second protrusion.

[0018] Effects of the Invention

[0019] According to the technology disclosed in the present invention, any of the following effects can be obtained.

[0020] (1) The opening distance on the substrate mounting surface side of the through-hole is larger than the opening distance on the capacitor body side. Therefore, the rising effect of the liquid level caused by the capillary phenomenon (hereinafter referred to as "the effect based on the capillary phenomenon") can be suppressed in the portion on the substrate mounting surface side of the through-hole. The force acting on the liquid or low-viscosity resin arranged between the terminal lead and the base can be suppressed.

[0021] (2) It is possible to suppress the movement of liquid or low-viscosity resin toward the outside of the base (substrate mounting surface) due to the capillary phenomenon.

[0022] (3) It is possible to prevent the resin that has moved to the outside (substrate mounting surface) of the base due to the capillary phenomenon from interfering with the soldering of the terminal leads.

[0023] (4) It is possible to suppress the migration of the resin due to the capillary phenomenon and reduce the amount of the resin filled in the capacitor. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a cross-sectional view showing an example of the capacitor according to the first embodiment.

[0025] Figure 2 It is a diagram showing a base of a capacitor.

[0026] Figure 3 yes Figure 2 Cross-sectional view along line aa in A.

[0027] Figure 4 It is a three-dimensional image of the base.

[0028] Figure 5 It is a diagram for explaining the effect of a capacitor.

[0029] Figure 6 This is a cross-sectional view showing an example of a capacitor according to the second embodiment.

[0030] Figure 7 1 is a cross-sectional view showing an example of a capacitor according to a modified example. DETAILED DESCRIPTION

[0031] Hereinafter, embodiments and the like will be described with reference to the drawings.

[0032] First embodiment

[0033] Figure 1 A is a cross-sectional view showing an example of the capacitor according to the first embodiment, Figure 1 B is Figure 1 A partial enlarged view of A. Figure 1 In A, a part of the capacitor body is omitted. Figure 2 A is a plan view of the base of the capacitor, showing a surface portion of the base that is provided on the main body installation surface of the capacitor body and on the sealing member side. Figure 2 B is a bottom view of the base, showing the surface opposite to the main body installation surface and the outer side surface (substrate mounting surface) of the base. Figure 3 Shows Figure 2 The aa line section in A. Figure 4 A and Figure 4 B is a three-dimensional diagram of the base. In order to explain the base, Figure 2 The base shown in A is added with an imaginary line L1, a midpoint O and a center line L2. Figure 1 and Figure 4 The structure shown is an example, and the technology disclosed in this disclosure is not limited to this structure.

[0034] The capacitor 2 is an example of an electronic component, such as an electrolytic capacitor or an electric double layer capacitor. The capacitor 2 includes a capacitor body 4, a base 6, and resin layers 8-1 and 8-2. The base 6 is provided on the capacitor body 4, the resin layer 8-1 is arranged in the gap between the base 6 and the capacitor body 4, and the resin layer 8-2 is arranged inside the through insertion hole formed in the base 6. The capacitor 2 can be mounted on a wiring board such as a circuit substrate.

[0035] The capacitor body 4 can be used as a capacitor in a single body. The capacitor body 4 includes an outer case 10 , a capacitor element 12 , and a sealing member 14 . The capacitor element 12 is sealed in the outer case 10 , and the sealing member 14 is attached to the opening of the outer case 10 .

[0036] The outer case 10 is, for example, a bottomed cylindrical aluminum case. The open front end of the outer case 10 is bent at a substantially right angle, so the end of the outer case 10 opposite to the bottom (hereinafter referred to as an "open end") has a flat surface.

[0037] Capacitor element 12 is a wound element in which anode foil, cathode foil and separator are wound with a separator interposed therebetween, and terminal leads 16 - 1 and 16 - 2 are led out from the same element surface. Capacitor element 12 is impregnated with an electrolyte solution.

[0038] The terminal leads 16-1 and 16-2 are formed of, for example, a metal with good conductivity. The terminal lead 16-1 is an anode-side terminal, and has a lead portion extending from the anode foil of the capacitor element 12 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 16-2 is a cathode-side terminal, and has a lead portion extending from the cathode foil of the capacitor element 12 and a terminal portion mounted on a wiring board. Similar to the terminal lead 16-1, 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 is, for example, flattened on the mounting surface side mounted on the wiring board so that the cross section is rectangular.

[0039] The sealing member 14 is formed of, for example, insulating rubber. The sealing member 14 has first insertion holes 17-1, 17-2 (hereinafter referred to as "insertion holes 17-1, 17-2") at positions corresponding to the terminal leads 16-1, 16-2. The terminal leads 16-1, 16-2 of the capacitor element 12 pass through the insertion holes 17-1, 17-2 of the sealing member 14 and are exposed to the outside of the capacitor body 4.

[0040] The base 6 is provided on the sealing member 14 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 only needs to have heat resistance to the extent that it can withstand heating when installed on a wiring board, and may be, for example, polyester resins such as polybutylene terephthalate (PBT), polybutylene naphthalate (PBN), and polyethylene terephthalate (PET), polyamide resins such as nylon, polyphenylene sulfide (PPS), polyphenylene oxide (PPO), urea resin, liquid crystal polymer (LCP), phenolic resin, or epoxy resin. The base 6 has second through-hole portions 18-1, 18-2 (hereinafter referred to as "through-hole portions 18-1, 18-2"), a first protrusion 20 (hereinafter referred to as "protrusion 20"), a peripheral wall 22, and guide grooves 24-1, 24-2. In addition, as Figure 2 As shown in FIG. 1A , the base 6 has supporting protrusions 26 - 1 and 26 - 2, a resin injection hole 30, a through hole 32 and a shielding portion 34. Figure 2 As shown in FIG. 8B , the base 6 has step portions 36 , 38 and a support portion 40 .

[0041] The insertion holes 18-1 and 18-2 are holes formed at positions corresponding to the terminal leads 16-1 and 16-2. The pair of terminal leads 16-1 and 16-2 protruding from the capacitor body 4 pass through the pair of insertion holes 18-1 and 18-2 formed in the base 6 and are led out to the outer side surface of the base 6, that is, the substrate mounting surface side of the base 6. The insertion holes 18-1 and 18-2 are formed separately as insertion holes for passing the terminal portions of the terminal leads 16-1 and 16-2.

[0042] The through-holes 18-1 and 18-2 have a step 42, so the opening distance D1 on the substrate mounting surface side of the through-hole is larger than the opening distance D2 on the capacitor body 4 side. The step 42 is formed on the inner side of the through-holes 18-1 and 18-2, and includes a step 42-1 arranged on the center side of the capacitor 2 and a step 42-2 arranged on the side of the capacitor 2. The width W1 of the step 42-1 is wider than the width W2 of the step 42-2. Since the width W2 is small, the thickness of the protrusion 20 between the through-holes 18-1 and 18-2 and the resin layer 8-1 is suppressed, thereby suppressing the area of ​​the surface of the protrusion 20 facing the sealing member 14. In addition, since the width W1 is large, the effect based on the capillary phenomenon is further suppressed.

[0043] In addition, the opening distance D2 is maintained as a small diameter, and the gap between the terminal leads 16-1, 16-2 and the insertion holes 18-1, 18-2 on the capacitor body 4 side becomes smaller. Therefore, the amount of resin that moves to the outside (substrate mounting surface) of the base 6 through the insertion holes 18-1, 18-2 can be suppressed. In the capacitor 2 after the resin is injected and before the resin is cured, the surface of the resin forming the resin layer 8-1 and the surface of the resin forming the resin layer 8-2 are sometimes different in height. For example, since the resin forming the resin layer 8-1 is filled in the gap between the base 6 and the capacitor body 4, its surface becomes the same height as the surface of the base 6 on the capacitor body 4 side (body setting surface). On the other hand, the surface of the resin forming the resin layer 8-2 is located at a lower position than the surface of the resin forming the resin layer 8-1, for example, on the capacitor body 4 side. In such a capacitor 2 where the height of the resin surface is different, when the resin forming the resin layer 8-1 is connected to the resin forming the resin layer 8-2, gravity plays a role in making the two surfaces of the resin uniform. That is, part of the resin forming the resin layer 8-1 with a higher surface moves to the insertion holes 18-1 and 18-2 via the communicating portion of the resin. However, since the opening distance D2 is small, the amount of resin moving to the insertion holes 18-1 and 18-2 can be suppressed.

[0044] In addition, due to the formation of the step portion 42, the opening distance D1 on the substrate mounting surface side of the through-hole (through-hole portion 18-1, 18-2) is larger than the opening distance D2 on the capacitor body 4 side, so the storage volume of the resin moved to the through-hole can be ensured on the substrate mounting surface side of the through-hole. Similar to the above, in the capacitor 2 where the surface height of the resin is different, the surface is uniformed due to gravity, and the resin in the through-hole moves to the guide grooves 24-1, 24-2. However, when the storage volume of the resin is larger due to the step portion 42, the movement of the resin to the guide grooves 24-1, 24-2 is suppressed, thereby preventing the resin from interfering with welding.

[0045] The distance D3 from the step portion 42 to the substrate mounting surface of the base 6 is greater than the distance D4 from the step portion 42 to the surface of the protrusion 20, that is, to the surface on the capacitor body 4 side. That is, the proportion of the portion with a larger opening distance is higher than 50%, so the proportion of the portion that suppresses the action based on the capillary phenomenon can be increased. The distance D4 can also be as thin as the thickness of the thinnest part of the protrusion 20 that separates the through-hole portions 18-1, 18-2 from the resin layer 8-1. The distance D4 is a distance greater than the thickness required to resist the pressure applied from the resin.

[0046] At a position closer to the capacitor body 4 than the step portion 42, as shown in FIG. Figure 2As shown in A, the cross section (hereinafter referred to as "body side cross section") through the insertion holes 18-1 and 18-2 is, for example, a rectangular shape with rounded corners. Figure 2 As shown in B, the shape of the cross section (hereinafter referred to as the "mounting surface side cross section") passing through the insertion hole portions 18-1 and 18-2 is, for example, a shape formed by two circles that overlap partially. The two circles have different sizes, and the larger circle contains the main body side cross section. The smaller of the two circles is arranged at a position closer to the center side of the capacitor 2 than the larger circle. As a whole, the end 43-1 of the mounting surface side cross section is arranged at a position separated from the end 43-2 of the main body side cross section to the outside. A step portion 42 is arranged at any portion between the end 43-1 of the mounting surface side cross section and the end 43-2 of the main body side cross section.

[0047] The protrusion 20 is provided on the main body installation surface of the base 6. The protrusion 20 is formed around the insertion holes 18-1 and 18-2, and surrounds the insertion holes 18-1 and 18-2. The protrusion 20 is opposite to the sealing member 14, and separates the resin layer 8-1 adjacent to the protrusion 20 from the insertion holes 18-1 and 18-2. The height of the protrusion 20 is set, for example, to a height difference H ( Figure 1 B). When the height of the protrusion 20 is the height difference H, the open end of the outer case 10 contacts the base 6, and the protrusion 20 of the base 6 contacts the sealing member 14. The outer case 10 and the protrusion 20 function as a support portion, whereby the arrangement of the base 6 is stable, and the capacitor body 4 is supported by both the peripheral portion and the central portion. In addition, the protrusion 20 in contact with the sealing member 14 can suppress the resin injected between the base 6 and the sealing member 14 to form the resin layer 8-1 from invading the insertion holes 18-1 and 18-2 at a high level.

[0048] The height of the protrusion 20 can be lower than the height difference H, or higher than the height difference H. The protrusion 20 that is lower than the height difference H can suppress the resin forming the resin layer 8-1 from invading the through-holes 18-1 and 18-2. In addition, a gap is formed between the protrusion 20 and the sealing member 14, and a flow path of air and resin to the through-holes 18-1 and 18-2 of the base 6 can be formed through the gap. The protrusion 20 that is higher than the height difference H contacts the sealing member 14, and can suppress the resin injected between the base 6 and the sealing member 14 from invading the through-holes 18-1 and 18-2 at a higher level. A gap is formed between the open end of the outer shell 10 and the base 6, and an air flow path can be formed through the gap.

[0049] For example Figure 2As shown in A of FIG. 1 , the protrusion 20 has a substantially rectangular shape with a constriction in the middle of the longitudinal direction. The protrusion 20 has a setback portion 44 in the middle of the longitudinal direction, and the setback portion 44 forms a constriction. The protrusion 20 has a flat portion 46 at the end of the longitudinal direction. For example, the protrusion 20 has a Figure 2 The imaginary line L1 shown in A is symmetrical in shape and has a shape relative to Figure 2 The shape is symmetrical about the center line L2 shown in A. The imaginary line L1 is a line connecting the insertion hole portion 18-1 and the insertion hole portion 18-2, and the center line L2 is a line passing through the middle point O of the insertion hole portion 18-1 and the insertion hole portion 18-2 and perpendicular to the imaginary line L1.

[0050] The protrusion 20 has grooves 48 and 50 on the surface facing the sealing member 14. The groove 48 is formed so that the height of the intermediate portion between the insertion hole 18-1 and the insertion hole 18-2 is partially lowered, and extends toward the resin injection hole 30 and the through hole 32 to form a resin passage. The groove 48 can adjust the flow rate of the resin flowing in the groove 48 according to the width of the groove 48.

[0051] The groove 50 extends from the flat portion 46 of the protrusion 20 to the insertion holes 18-1 and 18-2 to form an air passage. The groove 50 can discharge the air squeezed out by the resin injection to the outside through the groove 50. In order to form the resin layer 8-2, the groove 50 can also allow a part of the injected resin to pass through so that the resin reaches the insertion holes 18-1 and 18-2. The width, depth, setting interval or number of the groove 50 are appropriately set, for example, in consideration of the passage of air and the suppression of the intrusion of resin. The groove 50 is, for example, formed only on the surface of the through hole 32 side of the protrusion 20. Therefore, it is possible to suppress the resin from directly passing through the groove 50 and flowing to the insertion holes 18-1 and 18-2. That is, the resin injected from the resin injection hole 30 flows to the space on the through hole 32 side in the space between the sealing member 14 and the base 6 due to the injection pressure, and then the resin is pressed into the groove portion 50 due to the pressing force of the resin filled in the space, so that the resin can flow to the groove portion 50 at a pressure lower than the injection pressure. Therefore, the amount of resin flowing through the insertion holes 18-1 and 18-2 can be adjusted to a degree that the resin does not flow into the mounting surface of the base 6 and affect the connectivity between the terminal leads 16-1 and 16-2 and the wiring board.

[0052] The peripheral wall 22 is disposed around the base 6 and outside the open end of the outer casing 10, surrounding the open end of the outer casing 10. The inner side surface of the peripheral wall 22 follows the outer circumference of the bottomed cylindrical outer casing 10, and thus has a circular shape. Figure 3 As shown, the peripheral wall 22 may be higher than the protrusion 20 , or may be the same height as the protrusion 20 or lower than the protrusion 20 .

[0053] The guide grooves 24-1 and 24-2 are formed on the substrate mounting surface of the base 6 and extend outward from the second insertion holes 18-1 and 18-2. The terminal portions of the terminal leads 16-1 and 16-2 are bent in opposite directions along the guide grooves 24-1 and 24-2 and are arranged in the guide grooves 24-1 and 24-2. Therefore, the guide grooves 24-1 and 24-2 guide the terminal portions of the terminal leads 16-1 and 16-2. In addition, guide protrusions may be provided on the substrate mounting surface of the base 6 instead of the guide grooves 24-1 and 24-2. The stability of the capacitor 2 during installation can be ensured by the guide grooves 24-1 and 24-2 or the guide protrusions.

[0054] The support protrusions 26-1 and 26-2 are examples of protrusions that support the open end of the outer casing 10. The support protrusions 26-1 and 26-2 are adjacent to the resin layer 8-1 and are partially formed at a position where the base 6 contacts the open end of the outer casing 10. Figure 2 As shown in A, the support protrusions 26-1 and 26-2 are formed on the main body setting surface of the base 6 and are located closer to the inner side of the base 6 than the peripheral wall 22. The support protrusion 26-1 is in the shape of an arc having a width, and covers the outer side of the resin injection hole 30 and the protrusion 20 in the shape of an arc. The support protrusion 26-2 has a circular shape and is arranged on the outer side of the through hole 32. In the forming portion of the support protrusions 26-1 and 26-2, the open end of the outer shell 10 contacts the support protrusions 26-1 and 26-2. In the disconnected portion of the support protrusions 26-1 and 26-2, the open end of the outer shell 10 is separated from the base 6, and a gap is formed between the open end of the outer shell 10 and the base 6. The gap between the open end of the outer shell 10 and the base 6 forms a resin path for allowing the resin to flow between the peripheral wall 22 of the base 6 and the outer peripheral surface of the outer shell 10.

[0055] like Figure 2 As shown in A, the resin injection hole 30 is formed on the center line L2. The resin injection hole 30 is an example of a through hole for injecting resin, and the resin injection hole 30 is formed at an equal distance from the through hole portions 18-1 and 18-2.

[0056] like Figure 2 As shown in FIG. 1A , the through hole 32 is formed on the center line L2. The through hole 32 is formed, for example, at the terminal portion where the resin flows in the end during the resin injection, and is used to confirm the resin that has reached the terminal portion along the resin injection path. The through hole 32 is also used to discharge the air squeezed out by the resin injection. The through hole 32 makes it easy to confirm the resin filling state and to discharge the air.

[0057] The shielding portion 34 is disposed around the through hole 32 and between the through hole 32 and the resin injection hole 30. The shielding portion 34 prevents the resin injected from the resin injection hole 30 from invading the through hole 32 from the resin injection hole 30 side of the through hole 32. That is, the shielding portion 34 prevents the through hole 32 from being buried with the resin before the resin spreads throughout the formation area of ​​the resin layer 8-1. The shielding portion 34 surrounds a portion (e.g., two-thirds) of the periphery of the through hole 32. The shielding portion 34 preferably surrounds more than 50% of the periphery of the through hole 32, and preferably surrounds more than 66%. For example, Figure 2 As shown in A, for example, 10% of the periphery of the through hole 32 only needs to be open without being surrounded by the shielding portion 34 .

[0058] like Figure 2 As shown in FIG. 1B , a step portion 36 is formed on the substrate mounting surface of the base 6 and around the resin injection hole 30. The step portion 36 is used, for example, to align a resin injection device connected to the resin injection hole 30 during resin injection. The step portion 36 provides a space for preventing the resin near the resin injection hole 30 from protruding beyond the substrate mounting surface of the base 6.

[0059] like Figure 2 As shown in FIG. 1B , a step portion 38 is formed on the substrate mounting surface of the base 6 and around the through hole 32 . The step portion 38 provides a space for preventing the resin near the through hole 32 from protruding beyond the substrate mounting surface of the base 6 .

[0060] like Figure 2 As shown in B, the support portion 40 is formed on the substrate mounting surface of the base 6 and near the corner of the base 6. When the capacitor 2 is mounted on the wiring board, the support portion 40 can stabilize the posture of the capacitor 2 by point contact.

[0061] The resin layer 8-1 is provided on the outside of the protrusion 20 and on the inside of the open end of the outer casing 10, and is provided between the base 6 and the sealing member 14. The resin layer 8-1 makes the capacitor body 4 and the base 6 close to each other, and seals the outer side surface of the sealing member 14 together with the base 6. The resin layer 8-2 is provided inside the through-holes 18-1 and 18-2. The resin layer 8-2 fills the gap between the inner surface of the through-holes 18-1 and 18-2 and the terminal leads 16-1 and 16-2. Therefore, the sealing performance is improved, and the amount of gas passing through the through-holes 18-1 and 18-2 is suppressed. The resin layer 8-2 can be formed by allowing the resin injected from the resin injection hole 30 to reach the through-holes 18-1 and 18-2, or by adding resin from the substrate mounting surface of the base 6 to form the resin layer 8-2.

[0062] The resin forming the resin layers 8-1 and 8-2 is, for example, a sealing resin for sealing the outside of the sealing member 14. It is in liquid form when filling, but solidifies after filling. When filling, the liquid resin fills the gap between the capacitor body 4 and the base 6 and a part of the inside of the insertion holes 18-1 and 18-2. After filling, the resin solidifies to form the resin layers 8-1 and 8-2. The resin forming the resin layers 8-1 and 8-2 only needs to have affinity with the base 6, the outer casing 10 and the sealing member 14 and have gas blocking properties. It is preferred that the linear expansion coefficient is close to that of aluminum (about 23×10-6 / ℃), the shrinkage during curing is small, and it is non-hygroscopic. The resin can be, for example, epoxy resin, alkyd resin, polyurethane resin, thermosetting resin or ultraviolet curing resin. In addition, the epoxy resin can be, for example, a two-component mixed epoxy resin using anhydride, or a one-component epoxy resin.

[0063] [Capacitor manufacturing process]

[0064] The manufacturing process of the capacitor is an example of the manufacturing method of the capacitor disclosed in the present invention, and the manufacturing process includes a process of forming the capacitor body 4, a process of forming the base 6, a process of installing the base 6 on the capacitor body 4, a process of molding the terminal leads 16-1 and 16-2, and a process of injecting resin.

[0065] In the process of forming the capacitor body 4, first, a separator is interposed between an anode foil connected to the terminal lead 16-1 and a cathode foil connected to the terminal lead 16-2, and the anode foil, the cathode foil and the separator are wound to form the capacitor element 12. After the capacitor element 12 is impregnated with an electrolyte and the capacitor element 12 is sealed in the outer case 10, a sealing member 14 is attached to the opening of the outer case 10 to form the capacitor body 4. The outer case 10 is formed of aluminum, for example.

[0066] In the step of forming the base 6, the base 6 is formed into the above-mentioned shape by insulating synthetic resin. In addition, in the present embodiment, the electrolytic capacitor is formed by impregnating the capacitor element 12 with an electrolyte, but it is not limited to an electrolytic capacitor. The capacitor 2 may use the capacitor element 12 formed with a solid electrolyte layer by impregnating a conductive polymer as a solid electrolytic capacitor, or may be a hybrid capacitor in which the capacitor element 12 impregnated with a conductive polymer is impregnated with an electrolyte.

[0067] In the mounting step of the base 6, the terminal leads 16-1 and 16-2 of the capacitor body 4 are inserted through the insertion holes 18-1 and 18-2 of the base 6. Then, the base 6 is moved and mounted on the sealing member 14 side of the capacitor body 4. In this mounting step, the protrusion 20 of the base 6 is arranged on the sealing member 14 side.

[0068] In the molding process of the terminal leads 16-1, 16-2, the terminal leads 16-1, 16-2 are bent along the guide grooves 24-1, 24-2 of the base 6, and the terminal portions of the terminal leads 16-1, 16-2 are arranged in the guide grooves 24-1, 24-2. The base 6 is fixed to the capacitor body 4 by this molding process.

[0069] In the resin injection process, the liquid resin injected from the resin injection hole 30 of the base 6 is filled into the gap between the capacitor body 4 and the base 6. The resin spreads around the resin injection hole 30, and flows toward the through hole 32 through the gap between the protrusion 20 and the supporting protrusion 26-1 or the groove 48, thereby spreading around the through hole 32 and the shielding portion 34. In addition, a portion of the resin flows to the outside of the capacitor body 4 through the outside of the end of the supporting protrusion 26-1. In addition, a portion of the resin may also flow into the inside of the insertion holes 18-1 and 18-2 through the groove 50. The injected resin forms a resin layer 8-1 between the capacitor body 4 and the base 6, and forms a resin layer 8-2 inside the insertion holes 18-1 and 18-2. The resin is injected using a resin injection device such as a dispenser.

[0070] According to the first embodiment, the following operations or effects can be obtained.

[0071] (1) The opening distance D1 of the through-hole on the substrate mounting surface side is larger than the opening distance D2 on the capacitor body 4 side. Therefore, on the substrate mounting surface side, the force acting on the resin inside the through-hole due to the capillary phenomenon can be suppressed. When a thermosetting resin is used to form the resin layers 8-1 and 8-2, for example, the thermosetting resin whose viscosity decreases immediately before curing can be suppressed from receiving a force in the direction of the substrate mounting surface side.

[0072] (2) The resin penetrating the insertion hole can be prevented from moving to the outside of the base due to the capillary phenomenon. Therefore, the resin can be prevented from being arranged around the terminal leads arranged on the outside of the base (substrate mounting surface), thereby preventing the resin from interfering with the welding of the terminal leads.

[0073] (3) Since the migration of the resin can be suppressed, the amount of the filled resin can be suppressed from decreasing. The decrease and variation in the amount of the filled resin can be suppressed, and the quality of the capacitor can be made uniform.

[0074] (4) Figure 5 As shown in FIG. 1 , when the opening distance of the through-holes 18-1 and 18-2 is enlarged as a whole, the terminal portions of the terminal leads 16-1 and 16-2 may be inclined from the root along the bending direction of the terminal portions. Figure 5In the portion surrounded by the dotted line, the gap between the terminal leads 16-1, 16-2 and the insertion holes 18-1, 18-2 is narrowed, and capillary action is likely to occur. The step 42 of the insertion holes 18-1, 18-2 can suppress such inclination from the base of the terminal, thereby suppressing capillary action.

[0075] Second embodiment

[0076] Figure 6 2 is a cross-sectional view showing an example of a capacitor according to the second embodiment. Figure 6 In the diagram, part of the capacitor body is omitted. Figure 6 In, with Figure 1 The same parts are denoted by the same reference numerals. Figure 6 The structure shown is an example, and the technology disclosed in this disclosure is not limited to this structure.

[0077] The capacitor 2 of the first embodiment includes the protrusion 20 formed on the base 6 , but the capacitor 62 of the second embodiment includes a second protrusion 72 formed on the sealing member 68 instead of the protrusion 20 .

[0078] The capacitor 62 is an example of an electronic component, such as an electrolytic capacitor or an electric double layer capacitor. The capacitor 62 includes a capacitor body 64, a base 66, and resin layers 8-1 and 8-2. The base 66 is provided on the capacitor body 64, the resin layer 8-1 is arranged in the gap between the base 66 and the capacitor body 64, and the resin layer 8-2 is arranged inside the through insertion hole formed by the base 66 and the sealing member 68.

[0079] The capacitor body 64 is the same as the capacitor body 4 described in the first embodiment except for the sealing member 14. The capacitor body 64 includes a sealing member 68 instead of the sealing member 14. The description of the capacitor body 64 except for the sealing member 68 is omitted.

[0080] The sealing member 68 is formed of, for example, insulating rubber and has first insertion holes 70 - 1 and 70 - 2 (hereinafter referred to as “insertion holes 70 - 1 and 70 - 2 ”) and a second protrusion 72 (hereinafter referred to as “protrusion 72 ”).

[0081] Insertion holes 70 - 1 and 70 - 2 are formed at positions corresponding to terminal leads 16 - 1 and 16 - 2 . Terminal leads 16 - 1 and 16 - 2 of capacitor element 12 pass through insertion holes 70 - 1 and 70 - 2 of sealing member 68 and are exposed to the outside of capacitor body 64 .

[0082] The protrusion 72 is provided on the outer side of the sealing member 68. The protrusion 72 is formed around the insertion holes 70-1 and 70-2 and surrounds the insertion holes 70-1 and 70-2. The protrusion 72 contacts the base 66 and separates the resin layer 8-1 adjacent to the protrusion 72 from the insertion holes 70-1 and 70-2.

[0083] The base 66 is the same as the base 6 described in the first embodiment except for the protrusion 20. The base 66 does not include the protrusion 20 described in the first embodiment. Therefore, in the base 66, the insertion holes 18-1 and 18-2 are formed within the range of the plate thickness of the base 6.

[0084] The insertion holes 70-1 and 70-2 are connected to the insertion holes 18-1 and 18-2 of the base 66, respectively. The insertion holes 18-1 and 18-2 and the portions of the insertion holes 70-1 and 70-2 surrounded by the protrusions 72 form insertion holes for the terminal portions of the terminal leads 16-1 and 16-2. The insertion holes formed by the insertion holes 18-1 and 18-2 and the insertion holes 70-1 and 70-2 can be formed in the same shape as the insertion holes formed by the insertion holes 18-1 and 18-2 described in the first embodiment, for example, having the step portion 42 described in the first embodiment.

[0085] According to the second embodiment, the operations or effects described in the first embodiment can be obtained.

[0086] Regarding the above-mentioned embodiment, characteristic matters, advantages, modifications, etc. are listed below.

[0087] (1) In the first embodiment, the through-hole formed by the through-hole portions 18-1 and 18-2 has a step portion 42 in such a manner that the opening distance D1 on the substrate mounting surface side of the through-hole 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 described in the first embodiment. For example, Figure 7 As shown, the through-hole formed by the through-hole portion 74 may have an inclined surface 76 instead of the step portion 42, and the opening distance D1 of the through-hole on the substrate mounting surface side is larger than the opening distance D2 on the capacitor body 4 side. Similarly, in the above-mentioned second embodiment, the through-hole may have Figure 7 The inclined surface 76 shown is used instead of the step portion 42. In addition, the insertion hole may have a plurality of step portions formed in a step shape.

[0088] (2) In the above embodiment, the width W1 of the step portion 42-1 is larger than the width W2 of the step portion 42-2. However, the width W1 may be the same as the width W2, or the width W1 may be smaller than the width W2.

[0089] (3) In the above embodiment, the distance D3 from the step portion 42 to the substrate mounting surface of the base 6 is greater than the distance D4 from the step portion 42 to the surface of the protrusion 20. However, the distance D3 may be the same as the distance D4 or smaller than the distance D4.

[0090] (4) The materials for forming the base 6, 66, the resin layer 8-1, 8-2, the outer shell 10, and the sealing member 14, 68 are not limited to the above materials, and may be appropriately changed. Preferably, the base 6, 66 is transparent or translucent, and the resin layer 8-1, 8-2 is colored. For example, by using polycarbonate (PC) resin, the base 6, 66 can be made transparent or translucent. By using these bases 6, 66 and resin layers 8-1, 8-2, the filling state of the resin can be confirmed by means of the substrate mounting surface of the base 6, 66.

[0091] (5) The protrusion 20 only needs to surround the insertion holes 18-1 and 18-2, and the protrusion 72 only needs to surround the insertion holes 70-1 and 70-2. The shapes are not limited to the above shapes and can be changed appropriately. For example, the base 6 can have two first protrusions, and the two first protrusions respectively surround the insertion holes 18-1 and 18-2. The sealing member 68 can also have two second protrusions, and the two second protrusions respectively surround the insertion holes 70-1 and 70-2. In addition, the grooves 48 and 50 can also be provided as needed.

[0092] (6) In the above embodiment, the resin injection hole 30 is formed in the base 6, 66, and the resin is injected after the base 6, 66 is set on the capacitor body 4, 64 to form the resin layer 8-1, 8-2, but it can also be changed appropriately. It is also possible to make the resin adhere to the capacitor body 4, 64 or the base 6, 66, and then install the base 6, 66 on the sealing part 14, 68 side of the capacitor body 4, 64, and make the resin spread between the capacitor body 4, 64 and the base 6, 66, so that the gap between the capacitor body 4, 64 and the base 6, 66 is filled with resin. The resin that fills the gap between the capacitor body 4, 64 and the base 6, 66 forms the resin layer 8-1. According to this structure, it is not necessary to provide the resin injection hole 30.

[0093] As described above, the most preferred embodiments of the present disclosure have been described, but the technology of the present disclosure is not limited to the above description. A person skilled in the art can certainly make various modifications and changes based on the gist of the invention described in the claims or disclosed in the specification, and these modifications and changes are certainly included in the scope of the present disclosure.

[0094] Industrial Applicability

[0095] The technology disclosed herein can be widely used in electronic devices and is useful.

[0096] Description of symbols

[0097] 2, 62: capacitor; 4, 64: capacitor body; 6, 66: base; 8-1, 8-2: resin layer; 10: outer casing; 12: capacitor element; 14, 68: sealing member; 16-1, 16-2: terminal lead; 17-1, 17-2, 70-1, 70-2: first through-hole portion; 18-1, 18-2, 74: second through-hole portion; 20: first protrusion Part; 22: peripheral wall; 24-1, 24-2: guide groove; 26-1, 26-2: supporting protrusion; 30: resin injection hole; 32: through hole; 34: shielding part; 36, 38, 42, 42-1, 42-2: step portion; 40: supporting part; 43-1, 43-2: end; 44: retreat portion; 46: flat portion; 48, 50: groove portion; 72: second protrusion; 76: inclined surface.

Claims

1. A capacitor, characterized in that: The capacitor has: A capacitor body including an outer casing, a sealing member having a first insertion hole and mounted on an opening of the outer casing, and a terminal lead extending from the first insertion hole; a base, which is provided on the sealing member side of the capacitor body and has a second insertion hole portion through which the terminal lead is inserted and exposed to the substrate mounting surface side; as well as a resin layer disposed between the base and the sealing member, The resin layer is formed between the surface of the base and the outer side surface of the sealing member so that the capacitor body and the base are in close contact. The base includes a first protrusion surrounding the second insertion hole portion, and the second insertion hole portion of the base forms a through-hole, or the sealing member includes a second protrusion surrounding the first insertion hole portion and in contact with the base, and the second insertion hole portion of the base and the first insertion hole portion surrounded by the second protrusion form a through-hole, The resin layer is adjacent to the first protrusion or the second protrusion, The opening distance of the through-hole on the substrate mounting surface side is larger than the opening distance on the capacitor body side.

2. The capacitor according to claim 1, characterized in that The resin layer is further provided inside the insertion hole to fill a gap between an inner surface of the insertion hole and the terminal lead.

3. The capacitor according to claim 1 or 2, characterized in that: The insertion hole has a step portion or an inclined surface on an inner side surface of the insertion hole.

4. The capacitor according to claim 1 or 2, characterized in that: The difference in the opening distances on the outer side of the terminal lead is smaller than the difference in the opening distances on the central side of the terminal lead.

5. A method for manufacturing a capacitor, characterized in that: The manufacturing method of the capacitor has the following steps: manufacturing a capacitor body, the capacitor body comprising an outer casing, a sealing member having a first insertion hole and mounted on an opening of the outer casing, and a terminal lead extending from the first insertion hole; Making a base having a second through-hole portion; The base is arranged on the sealing member side of the capacitor body, and the terminal lead is inserted through the second insertion hole to be exposed to the substrate mounting surface side; as well as forming a resin layer disposed between the base and the sealing member and adjacent to the first protrusion or the second protrusion, The resin layer is formed between the surface of the base and the outer side surface of the sealing member so that the capacitor body and the base are in close contact. In the manufacture of the base, the first protrusion surrounding the second insertion hole is formed on the base, and the second insertion hole of the base forms a through-hole, or, in the manufacture of the capacitor body, the second protrusion surrounding the first insertion hole and having a height for contacting the base is formed on the sealing member, and the second insertion hole of the base and the first insertion hole surrounded by the second protrusion form a through-hole, The opening distance of the through-hole on the substrate mounting surface side is larger than the opening distance on the capacitor body side.

6. The method for manufacturing a capacitor according to claim 5, wherein: The resin layer is further provided inside the insertion hole to fill a gap between an inner surface of the insertion hole and the terminal lead.

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