WO2024058236A1

WO2024058236A1 - Capacitor and method for manufacturing same

Info

Publication number: WO2024058236A1
Application number: PCT/JP2023/033473
Authority: WO
Inventors: 庸平橋本
Original assignee: 日本ケミコン株式会社
Priority date: 2022-09-16
Filing date: 2023-09-14
Publication date: 2024-03-21
Also published as: JP2024042805A

Abstract

The purpose of the present invention is to increase the proportion of a sealing member covered by a resin layer, and to inhibit leakage of the resin to the outside of a pedestal, for example.　A capacitor body (4) includes an external case (12), a sealing member (16), and a plurality of terminal leads (18-1, 18-2). A pedestal (6) includes: a plurality of insertion holes (36-1, 36-2) which are installed in the capacitor body on the sealing member side, and through which the respective terminal leads are inserted; a plurality of protrusions (38-1, 38-2) surrounding the respective through-holes; a resin injection hole (26) used for the injection of a resin (60); a through-hole (28) used for the confirmation of the injected resin; and a shielding part (30) surrounding the through-hole. A resin layer (8) is disposed between the pedestal and the sealing member. The resin layer extends to at least a portion of a gap between the sealing member and a top surface (30-1) of the shielding part.

Description

Capacitor and its manufacturing method

The present disclosure relates to a capacitor including a pedestal and a resin layer, and a method for manufacturing the same.

A capacitor equipped with a pedestal includes, for example, a terminal lead drawn out and bent on the outer surface of the pedestal (that is, the board mounting surface). This terminal lead is soldered to a wiring board such as a circuit board, and the capacitor is mounted on the wiring board. Such a capacitor is called a surface-mounted capacitor, and has high versatility, and is used, for example, in automobiles.

When a capacitor is installed outdoors, such as inside a car, the environmental temperature around the capacitor increases. Therefore, capacitors must withstand high temperature environments. For example, a capacitor includes a resin layer formed between a sealing member and a pedestal, and the sealing performance of the capacitor is improved (for example, Patent Document 1). According to such a configuration, the heat resistance of the capacitor can be improved.

Japanese Unexamined Patent Publication No. 60-245121

Incidentally, as the coverage ratio of the resin layer to the sealing member increases, the sealing performance of the capacitor increases. In other words, in a capacitor including a resin layer, there is a problem of how to increase the coverage ratio of the resin layer to the sealing member. Furthermore, if resin leaking from holes in the pedestal through which terminal leads pass interferes with mounting on a wiring board, there is a problem in that the resin on the outside of the pedestal must be removed.

Therefore, an object of the technology of the present disclosure is, for example, to increase the coverage ratio of the resin layer to the sealing member and to suppress leakage of resin to the outside of the pedestal.

According to the first aspect of the present disclosure, a capacitor includes a capacitor body, a pedestal, and a resin layer. The capacitor main body includes an outer case, a sealing member attached to an opening of the outer case, and a plurality of terminal leads protruding from the sealing member. The pedestal is installed on the sealing member side of the capacitor body, and has a plurality of insertion holes through which the plurality of terminal leads are inserted, a plurality of protrusions each surrounding the plurality of insertion holes, and a pedestal used for resin injection. It includes a resin injection hole, a through hole used for checking the injected resin, and a shielding part that surrounds the through hole. A resin layer is arranged between the base and the sealing member. The resin layer extends in at least a portion of the gap between the sealing member and the top surface of the shielding part.

In the above capacitor, the shielding distance of the shielding part in the first region may be longer than the shielding distance of the shielding part in the second region. The first region is defined as a region between the resin injection hole and the through hole and a region overlapping the through hole, and the second region is defined as a region other than the first region.

In the above capacitor, the shielding part may have a lid part that covers the through hole, and the lid part may make a shielding distance in the first region longer than a shielding distance in the second region.

In the above capacitor, the shielding portion may have a separation portion on a center line passing through the center of the resin injection hole and the center of the through hole, and on the peripheral side of the pedestal. The minimum cross-sectional area of any one of the plurality of insertion holes, or the minimum cross-sectional area of the gap between the insertion hole and the terminal lead inserted into the insertion hole, is surrounded by the top surface of the shielding part. The area may be smaller than the total area of the top opening area formed by the spacer and the side opening area formed by the spacer.

In the above capacitor, each terminal lead may be bent at a bent portion. Each insertion hole may have a step at a position adjacent to the bent portion and closer to the sealing member than the bent portion.

In the above-described capacitor, each insertion hole may include a small hole portion disposed closer to the sealing member than the step portion, and a large hole portion in which the bent portion is disposed. The resin layer may extend over at least a portion of the small hole. The bent portion may be exposed without contacting the resin layer.

According to a second aspect of the present disclosure, a capacitor manufacturing method includes a capacitor body including an outer case, a sealing member attached to an opening of the outer case, and a plurality of terminal leads protruding from the sealing member. a plurality of insertion holes, a plurality of protrusions surrounding the plurality of insertion holes, a resin injection hole used for resin injection, and a penetration used for checking the injected resin. a step of manufacturing or preparing a pedestal including a hole and a shielding part surrounding the through hole, and installing the pedestal on the sealing member side of the capacitor body, and inserting the plurality of terminal leads into each of the plurality of insertion holes. and injecting the resin from the resin injection hole to form a resin layer between the base and the sealing member, and at least filling the gap between the sealing member and the top surface of the shielding part. and a step of extending the resin layer in a portion.

According to the technology of the present disclosure, for example, the plurality of insertion holes and the through-holes are respectively surrounded by the plurality of protrusions and the shielding part, and at least part of the gap between the sealing member and the top surface of the shielding part is Since the resin layer is extended, leakage of the resin is suppressed, and the area covered by the resin layer over the surface of the sealing member is increased, so that the sealing performance of the capacitor is improved.

FIG. 3 is a diagram showing an example of a capacitor according to an embodiment. 2 is a diagram showing a cross section taken along line II-II in FIG. 1. FIG. 2 is a diagram showing a cross section taken along the line III-III in FIG. 1. FIG. It is a perspective view of a pedestal. FIG. 7 is a diagram for explaining the area of the insertion hole and the shielding distance of the shielding part. FIG. 3 is a diagram showing an example of a resin injection step in a capacitor manufacturing process. FIG. 6 is an image diagram for explaining changes in the filling state of resin.

FIG. 1 shows an example of a capacitor according to an embodiment, FIG. 2 shows a cross section taken along line II-II in FIG. 1, and FIG. 3 shows a cross section taken along line III-III in FIG. In FIGS. 2 and 3, a portion of the capacitor body 4 is omitted. FIG. 4 is a perspective view of the pedestal. A in FIG. 4 shows the main body installation surface (that is, the surface on the sealing member side of the pedestal) installed on the capacitor main body. B in FIG. 4 shows the surface opposite to the main body installation surface (that is, the outer surface of the pedestal or the board mounting surface). The configurations shown in FIGS. 1 to 4 are examples, and the technology of the present disclosure is not limited to such configurations. In this specification, the side where the capacitor body is located is treated as the "upper side" of the capacitor, the side where the pedestal is located is treated as the "lower side" of the capacitor, and the "plane" and "bottom" on the drawings are Defined.

The capacitor 2 is an example of an electronic component, such as an electrolytic capacitor or an electric double layer capacitor. This capacitor 2 includes a capacitor body 4, a pedestal 6, and a resin layer 8. The pedestal 6 is installed on the capacitor body 4, and the resin layer 8 is arranged in the gap between the pedestal 6 and the capacitor body 4. Capacitor 2 can be mounted on a wiring board such as a circuit board.

The capacitor body 4 can be used alone as a capacitor. This capacitor body 4 includes an exterior case 12, a capacitor element 14, and a sealing member 16. A capacitor element 14 is enclosed within the outer case 12, and a sealing member 16 is attached to the opening of the outer case 12.

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.

The capacitor element 14 includes a wound element which is wound with a separator interposed between an anode foil and a cathode foil, and terminal leads 18-1 and 18-2 led out from the same element surface of the wound element. This capacitor element 14 is impregnated with an electrolytic solution.

The terminal leads 18-1 and 18-2 are made of, for example, a highly conductive metal. The terminal lead 18-1 is an anode side terminal and includes a lead portion drawn out from the anode foil of the capacitor element 14 and a terminal portion mounted on the 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 out from the cathode foil of the capacitor element 14 and a terminal portion mounted on the wiring board. The lead portion and the terminal portion are connected and integrated by welding or the like. The lead portion has, for example, a cylindrical cross section. The terminal portions of the terminal leads 18-1 and 18-2 are bent in opposite directions and include a bent portion 20 and an exposed terminal portion 22 disposed on the tip side of the bent portion 20. The terminal portion has, for example, a rectangular cross section in the exposed terminal portion 22 . That is, in the exposed terminal portion 22, the terminal portion is flattened and can face the wiring board in a plane, for example. The terminal portion has, for example, a circular cross section in a portion closer to the lead portion than the bent portion 20 .

The sealing member 16 is made of, for example, insulating rubber. The sealing member 16 has insertion holes 24-1 and 24-2 at positions corresponding to the terminal leads 18-1 and 18-2. The terminal leads 18-1 and 18-2 pass through the insertion holes 24-1 and 24-2, respectively, and protrude from the sealing member 16.

The pedestal 6 is installed on the sealing member 16 side of the capacitor body 4. The pedestal 6 is made of an insulating material such as an insulating synthetic resin. This insulating synthetic resin only needs to have enough heat resistance to withstand heating when mounted on a wiring board, such as polybutylene terephthalate (PBT), polybutylene naphthalate (PBN), or polyethylene terephthalate (PET). These include polyester resins such as, polyamide resins such as nylon, polyphenylene sulfide (PPS), polyphenylene oxide (PPO), urea resin, liquid crystal polymer (LCP), phenol resin, and epoxy resin. The pedestal 6 has a resin injection hole 26, a through hole 28, a shielding part 30,

step parts

32, 34, insertion holes 36-1, 36-2, protrusions 38-1, 38-2, and a step. 39, guide grooves 40-1 and 40-2, a support portion 42, and a peripheral wall 44.

The resin injection hole 26 is an example of an insertion hole used for injection of the resin 60 (B in FIG. 6), and is formed, for example, at an equal distance from the insertion holes 36-1 and 36-2. Resin 60 injected from resin injection hole 26 spreads into the gap between capacitor body 4 and pedestal 6, and resin layer 8 is formed.

The through hole 28 is formed, for example, at the terminal end where the resin 60 flows last in resin injection, and is used to check the resin 60 that has reached the terminal end along the injection route of the resin 60. The through hole 28 is also used to discharge the air pushed out by the injection of the resin 60, and the through hole 28 makes it easy to confirm the filling state of the resin 60 and also facilitates the discharge of the air.

The shielding part 30 is installed on the main body installation surface of the pedestal 6 and faces the sealing member 16. The shielding portion 30 is disposed around the through hole 28 and between the through hole 28 and the resin injection hole 26, and prevents the resin 60 from entering the through hole 28 from the resin injection hole 26 side. In other words, the shielding portion 30 prevents the through hole 28 from being filled with the resin 60 before the resin 60 reaches the region where the resin layer 8 is formed. The shielding section 30 includes a top surface 30-1 facing the sealing member 16, a separating section 30-2, and a lid section 30-3. The height of the shielding portion 30 is, for example, 0.1 to 0.6 mm lower than the height difference between the outer surface of the sealing member 16 and the main body installation surface of the pedestal 6. Therefore, a gap is formed between the top surface 30-1 of the shielding part 30 and the sealing member 16, and the resin layer 8 extends into the gap between the top surface 30-1 and the sealing member 16 due to the intrusion of the resin 60. Can be done. The sealing performance of the capacitor 2 is improved by filling the gap with the resin 60.

The spacing portion 30-2 is located on the center line passing through the center of the resin injection hole 26 and the center of the through hole 28 and on the peripheral side of the pedestal 6 (that is, the farthest position from the center O of the capacitor 2). . The shielding part 30 surrounds the through hole 28 except for this separation part 30-2. Therefore, the tip of the injected resin 60 is basically guided near the separation part 30-2, and reaches the through hole 28 through the separation part 30-2. In other words, the shielding part 30 having the separating part 30-2 makes it easier for the resin 60 to spread throughout the gap between the base 6 and the sealing member 16. The separation distance of the separation part 30-2 (that is, the separation distance between both ends of the curved shielding part 30) is, for example, 1 to 3 times the width of the resin passage immediately in front of the separation part 30-2. By narrowing the separation distance, air remaining in the vicinity of the separation portion 30-2 is suppressed.

The lid portion 30-3 is arranged in an area overlapping the through hole 28, and covers the through hole 28. The surface of the lid portion 30-3 forms a part of the top surface 30-1. When the ratio at which the lid part 30-3 shields the through hole 28 (hereinafter referred to as "shielding ratio") is large, the ratio of the space remaining between the top surface 30-1 of the shielding part 30 and the sealing member 16 increases. . If the shielding rate is small, the through hole 28 will be filled with the resin 60 that has passed over the shielding part 30 before the resin 60 flows through the resin passage just before the separating part 30-2. The appropriate range of shielding rate depends on the size of the gap between the top surface 30-1 and the sealing member 16 (for example, 0.1 to 0.6 mm), the viscosity and type of the resin 60 to be injected, and the injection pressure of the resin 60. , and related factors such as the diameter of the through hole 28 (eg, 1.0 to 1.5 mm) and the height of the shield 30 (eg, 0.6 to 1.2 mm). The inventor of the present application has found from the experimental results of the shielding rate that the appropriate range of the shielding rate is, for example, 40 to 80%. Therefore, the shielding rate may be narrowed down from the range of 40% to 80% through experiments after determining the related factors mentioned above. Alternatively, the shielding rate may be determined to be a central range (for example, 50% to 70%) or a median value (60%) in a range of 40% to 80%.

As shown in FIG. 5A, when the area overlapping the through hole 28 and the area around the through hole 28 are divided into a first area 46 and a second area 48, the shielding part 30 in the first area 46 is shielded. The distance L1 is longer than the shielding distance L2 of the shielding part 30 in the second region 48, and for example, the lid part 30-3 makes the shielding distance L1 longer than the shielding distance L2. The first region 46 is defined as a region between the resin injection hole 26 and the through hole 28 and the region overlapping the through hole 28, and the second region 48 is defined as a region other than the first region 46. Since the shielding distance L1 is longer than the shielding distance L2, the resin shielding function of the shielding part 30 in the first region 46 is higher than the resin shielding function of the shielding part 30 in the second region 48. The shielding distance L1 may be a distance that varies depending on the position, such as the shielding part 30 in the first region 46, or may be a constant distance, such as the shielding part 30 in the second region 48, for example. The shielding distance L2 is, for example, a constant distance, or may be a distance that varies depending on the position.

The stepped portion 32 is the substrate mounting surface of the pedestal 6 and is formed around the resin injection hole 26. The stepped portion 32 is used, for example, for positioning a resin injection device connected to the resin injection hole 26 during resin injection. The stepped portion 32 provides a space to prevent the resin 60 near the resin injection hole 26 from protruding beyond the board mounting surface of the pedestal 6.

The stepped portion 34 is the board mounting surface of the pedestal 6 and is formed around the through hole 28. The stepped portion 34 provides a space to prevent the resin 60 near the through hole 28 from protruding beyond the board mounting surface of the pedestal 6.

The insertion holes 36-1 and 36-2 are holes formed at positions corresponding to the terminal leads 18-1 and 18-2. The terminal leads 18-1 and 18-2 protruding from the capacitor body 4 pass through the insertion holes 36-1 and 36-2, respectively, and are pulled out to the outer side of the pedestal 6, that is, to the board mounting surface of the pedestal 6. ing. The insertion holes 36-1 and 36-2 are spaced apart from a center line passing through the center of the resin injection hole 26 and the center of the through hole 28, and are arranged, for example, in line symmetry with respect to this center line. .

The protrusions 38-1 and 38-2 are installed on the main body installation surface of the pedestal 6 and face the sealing member 16. The protrusion 38-1 is formed around the insertion hole 36-1, surrounds the insertion hole 36-1, and separates the resin layer 8 from the insertion hole 36-1. The protrusion 38-2 is formed around the insertion hole 36-2, surrounds the insertion hole 36-2, and separates the resin layer 8 from the insertion hole 36-2. The height of the protrusions 38-1 and 38-2 is, for example, slightly smaller than the height difference between the outer surface of the sealing member 16 and the main body installation surface of the pedestal 6 (for example, 0.1 to 0.3 mm). )low. Therefore, gaps are formed between the protrusions 38-1, 38-2 and the sealing member 16. The resin 60 injected from the resin injection hole 26 can enter the gap between the protrusions 38-1, 38-2 and the sealing member 16, and the resin layer 8 can extend into this gap. The sealing performance of the capacitor 2 is improved by filling the gap with the resin 60.

The protrusions 38-1 and 38-2 have a plurality of grooves 50 on the surface facing the sealing member 16. The groove portion 50 extends from the outer surface of the protrusion portions 38-1 and 38-2 to the insertion holes 36-1 and 36-2 to form a ventilation passage or a resin passage. The groove portion 50 can guide air or resin 60 pushed out by resin injection to the insertion holes 36-1 and 36-2. The width, depth, installation interval, or number of grooves 50 may be appropriately set in consideration of the amount of air or resin 60 passing through, and for example, three to eight grooves are suitable. Further, it is preferable that the groove portion 50 is not provided in a portion facing the resin injection hole 26 . The portion facing the resin injection hole 26 is also a place where the resin 60 injected from the resin injection hole 26 flows linearly. Therefore, if the groove portion 50 is installed in a portion facing the resin injection hole 26, the resin 60 easily enters the insertion holes 36-1, 36-2, and the resin 60 enters the insertion holes 36-1, 36-2. There is a risk of it leaking out. However, by not forming the groove portion 50 in the portion facing the resin injection hole 26, such a phenomenon can be further suppressed. The insertion holes 36-1 and 36-2 have a stepped portion 52, a small hole portion 54 located closer to the sealing member 16 than the stepped portion 52, and a small hole portion 54 located closer to the board mounting surface than the stepped portion 52. The large hole portion 56 is included.

The stepped portion 52 is arranged at a position closer to the sealing member 16 than the bent portion 20 of the terminal leads 18-1, 18-2 and adjacent to the bent portion 20. The stepped portion 52 prevents the resin 60 in the insertion holes 36-1 and 36-2 from moving to the board mounting surface due to capillary action. The stepped portion 52 has a width W1 on the center O side of the capacitor 2, and has a width W2 on the side side of the capacitor 2. The width W1 is larger than the width W2, for example, so that a space near the bent portion 20 on the center O side of the capacitor 2 is secured.

In a plane parallel to the main body installation surface and the board mounting surface, the small hole portion 54 has, for example, a rectangular cross-sectional shape with rounded corners, and the cross-section of the terminal portions of the terminal leads 18-1 and 18-2 (rectangular (shaped cross section and circular cross section). The cross-sectional area S1 of the small hole 54 shown in A of FIG. 5 is the area of the small hole 54 in a plane parallel to the main body installation surface and the board mounting surface, and satisfies, for example, the following formula (1). . The cross-sectional area S1 is the minimum cross-sectional area of the insertion hole 36-1 or the insertion hole 36-2.
S1<S2+S3...(1)
S2: Top opening area surrounded by the top surface 30-1 of the shielding part 30 S3: Side opening area formed by the separating part 30-2

When the cross-sectional area S1 is smaller than the total area of the top opening area S2 and the side opening area S3, a certain degree of flow resistance is obtained in the small hole portion 54. The small hole portion 54 extends to the step portion 52 adjacent to the bent portion 20 and has a relatively large height H. Therefore, the distance of the region having flow resistance becomes longer, and the effect of suppressing the invasion of the resin 60 becomes higher. Intrusion of the resin 60 can be prevented in the small holes 54.

In a plane parallel to the main body installation surface and the board mounting surface, it is preferable that the cross-sectional area S4 of the gap between the small hole 54 and the terminal lead 18-1 or the terminal lead 18-2 satisfies the following formula (2).
S4=S1-S5<S2+S3...(2)
S5: Cross-sectional area of terminal lead 18-1 or terminal lead 18-2 in small hole 54

If the cross-sectional area S4 is smaller than the total area of the top opening area S2 and the side opening area S3, the flow resistance of the resin 60 in the small hole portion 54 will be greater than the flow resistance of the resin 60 in the through hole 28, for example. Therefore, the distance of the region having high flow resistance becomes longer, and the effect of suppressing the invasion of the resin 60 becomes even higher.

The step 39 is formed around the protrusions 38-1 and 38-2 and between the protrusions 38-1 and 38-2. The step 39 adjusts, for example, the flow rate of the resin 60 passing through the gap between the protrusions 38-1 and 38-2. Furthermore, the step 39 provides the pedestal 6 with a thickness necessary for forming the step portion 52, for example. The step 39 may have an inclined surface 57, for example. The inclined surface 57 alleviates the collision of the resin 60 with the step 39 and suppresses air remaining in the vicinity of the step 39.

The guide grooves 40-1 and 40-2 are formed on the board mounting surface of the pedestal 6 and extend from the insertion holes 36-1 and 36-2 to the outside (toward the outer edge of the pedestal 6). The exposed terminal portions 22 of the bent terminal leads 18-1 and 18-2 are arranged in the guide grooves 40-1 and 40-2. Note that the guide grooves 40-1 and 40-2 may be formed by a plurality of guide protrusions formed on the outside of the exposed terminal portion 22. The guide grooves 40-1 and 40-2 contribute to ensuring the stability of the capacitor 2 during mounting.

The peripheral wall 44 is disposed around the pedestal 6 and 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 44 has a circular shape in order to fit along the outer periphery of the bottomed cylindrical outer case 12. The peripheral wall 44 may be higher than the protrusions 38-1, 38-2, the same height as the protrusions 38-1, 38-2, or lower than the protrusions 38-1, 38-2.

The support portion 42 is the board mounting surface of the pedestal 6 and is formed near the corner of the pedestal 6. The support portion 42 can stabilize the posture of the capacitor 2 through point contact when the capacitor 2 is mounted on the wiring board. When the support portion 42 contacts the wiring board, the exposed terminal portions 22 of the terminal leads 18-1 and 18-2 are slightly separated from the wiring board. This gap between the exposed terminal portion 22 and the wiring board makes it possible to ensure the thickness of the solder necessary for connection.

The resin layer 8 is provided inside the open end of the exterior case 12 and between the pedestal 6 and the sealing member 16. This resin layer 8 brings the capacitor body 4 and the pedestal 6 into close contact with each other, and seals the outer surface of the sealing member 16 together with the pedestal 6. Further, the resin layer 8 strengthens the bonding force of the pedestal 6 to the outer case 12 and the sealing member 16, and improves the integrity of the capacitor body 4 and the pedestal 6. The resin layer 8 may partially seal the outer surface of the sealing member 16 alone.

The resin layer 8 extends, for example, to a part or all of the small holes 54 of the insertion holes 36-1 and 36-2, thereby improving the sealing performance of the capacitor 2. For example, the resin layer 8 does not extend into the large hole 56, and the bent portions 20 of the terminal leads 18-1 and 18-2 are exposed without being covered with the resin 60. Since the bent portion 20 is exposed, solder can be attached to the bent portion 20, and the connection strength of the capacitor 2 using solder can be increased. The high connection strength of the capacitor 2 increases the vibration resistance of the capacitor 2, for example.

The resin 60 forming the resin layer 8 is, for example, a sealing resin that seals the outside of the sealing member 16, and is liquid during filling, but solidifies after filling. During filling, liquid resin 60 fills the gap between capacitor body 4 and pedestal 6 and part or all of small hole 54, and after filling, resin 60 solidifies to form resin layer 8. The resin 60 forming the resin layer 8 has an affinity for the pedestal 6, the exterior case 12, and the sealing member 16, and only needs to have gas barrier properties, and has a linear expansion coefficient of aluminum (approximately 23×10 ^-6 It is preferable that the material has a coefficient of linear expansion close to 0.2°C/°C), has a small amount of shrinkage upon curing, and is non-hygroscopic. The resin 60 may be, for example, an epoxy resin, an alkyd resin, a urethane resin, a thermosetting resin, or an ultraviolet curing resin. Further, the epoxy resin may be a two-part mixed type epoxy resin using an acid anhydride, or a one-part type epoxy resin. The resin layer 8 formed from such a material has heat resistance in a solidified state to the heat treatment temperature (for example, 270° C.) used when installing the capacitor 2 on a wiring board.

FIG. 6 shows an example of the resin 60 injection process in the capacitor manufacturing process. FIG. 7 shows an image for explaining changes in the filling state of the resin 60. The steps shown in FIG. 6 and the images shown in FIG. 7 are merely examples, and the technology of the present disclosure is not limited to the steps shown in FIG. 6 and the images shown in FIG. do not have.

The capacitor manufacturing process is an example of the capacitor manufacturing method of the present disclosure, and includes the steps of manufacturing the capacitor body 4, manufacturing the pedestal 6, attaching the pedestal 6, and terminal leads 18-1, 18. -2 molding process, resin 60 injection process, and resin 60 curing process.

In the manufacturing process of the capacitor body 4, first, a separator is interposed between the anode foil to which the terminal lead 18-1 is connected and the cathode foil to which the terminal lead 18-2 is connected, and these are wound to form the capacitor element 14. do. After impregnating the capacitor element 14 with an electrolytic solution and enclosing the capacitor element 14 in the outer case 12, the sealing member 16 is attached to the opening of the outer case 12, and the capacitor body 4 is manufactured and prepared. Exterior case 12 is made of aluminum, for example.

In the step of manufacturing the pedestal 6, the pedestal 6 is prepared by, for example, manufacturing the pedestal 6 having the above-described shape from an insulating synthetic resin by resin molding using a mold.

In the step of attaching the pedestal 6, the terminal leads 18-1 and 18-2 of the capacitor body 4 are passed through the insertion holes 36-1 and 36-2 of the pedestal 6. Then, the pedestal 6 is moved and attached to the sealing member 16 side of the capacitor body 4. In this attachment process, the protrusions 38-1 and 38-2 of the base 6 are placed on the sealing member 16 side.

In the process of forming the terminal leads 18-1, 18-2, the terminal leads 18-1, 18-2 are bent along the guide grooves 40-1, 40-2 of the base 6. The bent portions 20 of the terminal leads 18-1 and 18-2 are formed in the large hole portion 56 at a position adjacent to the stepped portion 52, and the exposed terminal portions 22 of the terminal leads 18-1 and 18-2 are formed in the large hole portion 56. It is arranged in guide grooves 40-1 and 40-2. This molding process fixes the pedestal 6 to the capacitor body 4.

In the step of injecting the resin 60, the movement of the capacitor body 4 is restricted, and the resin discharging part 58 of a resin discharging device such as a dispenser is pressed against the resin injection hole 26 of the pedestal 6, as shown in FIG. 6A. Then, liquid resin 60 is injected from the resin injection hole 26. Liquid resin 60 is filled into the gap between capacitor body 4 and pedestal 6. As shown in FIG. 6B, FIG. 7A, and FIG. 7B, the resin 60 spreads around the resin injection hole 26, partially collides with the protrusions 38-1 and 38-2, and partially The water flows to the through hole 28 side between the protrusions 38-1 and 38-2 and through the outside of the protrusions 38-1 and 38-2.

As shown in FIG. 7A, the resin 60 that has collided with the protrusions 38-1 and 38-2 enters the gap between the protrusions 38-1 and 38-2 and the sealing member 16, and resists flow. As a result, it stops within this gap or small hole 54. The resin 60 that has passed between the protruding parts 38-1 and 38-2 collides with the shielding part 30 and is split into left and right parts, and also enters the gap between the top surface 30-1 of the shielding part 30 and the sealing member 16. . The resin 60 between the top surface 30-1 and the sealing member 16 decelerates or stops due to flow resistance. The left and right resin 60 basically moves toward the separation part 30-2 along the shielding part 30, so that it does not collide with the shielding part 30 with strong force. Therefore, even if the shielding distance L2 of the shielding part 30 is shorter than the shielding distance L1, the resin 60 is prevented from entering between the top surface 30-1 and the sealing member 16. The resin 60 that has passed outside the protrusions 38-1 and 38-2 heads along the edge of the sealing member 16 toward the separation part 30-2. As shown in FIG. 7B, in the final step of the resin 60 injection process, the resin 60 is filled except for the spaced portion 30-2 and its vicinity. The resin 60 finally reaches the separation part 30-2 and enters the through hole 28.

In the step of injecting the resin 60, for example, a surveillance camera monitors the inside of the through hole 28. As shown in FIG. 6C, for example, when the resin 60 is confirmed throughout the through hole 28, the injection of the resin 60 is stopped. When the resin 60 is confirmed in a part of the inside of the through hole 28, the injection of the resin 60 may be stopped. By stopping the resin injection, the resin 60 injection process is completed.

In the step of curing the resin 60, the injected resin 60 is heated, for example. The viscosity of the heated resin 60 decreases before curing. The resin 60 having a lower viscosity may increase the amount of the resin 60 in the gap between the protrusions 38-1, 38-2 and the sealing member 16, and increase the amount of the resin 60 in the small hole 54. The amount of resin 60 in the gap between the top surface 30-1 and the sealing member 16 may be increased, or the amount of resin 60 in the through hole 28 may be increased. That is, in the curing process of the resin 60, the ratio at which the resin 60 or the resin layer 8 covers the outer surface of the sealing member 16 (hereinafter referred to as "coverage") may be increased. The stepped portions 52 of the insertion holes 36-1 and 36-2 can suppress the movement of the resin 60 whose viscosity has been reduced due to capillarity, and can suppress the resin 60 from entering the large hole portions 56.

According to the embodiment, for example, the following effects can be obtained.

(1) The resin layer 8 covers the gaps between the protrusions 38-1 and 38-2 and the sealing member 16, the inside of the small hole 54, and the gap between the top surface 30-1 of the shielding part 30 and the sealing member 16, Since the resin layer 8 extends inside the through hole 28, the area that the resin layer 8 covers the surface of the sealing member 16 and the above-mentioned coverage increase, and the sealing performance of the capacitor 2 is improved.

(2) Since the cross-sectional area S1 or the cross-sectional area S4 is suppressed, the flow resistance in the small hole portion 54 is relatively high. Furthermore, since the height H of the small hole portion 54 is relatively large, the length of the region having relatively high flow resistance is relatively long. Therefore, the movement of the resin 60 in the small hole 54 can be suppressed, and the extension end of the resin layer 8 can be suppressed to the small hole 54.

(3) Since the bent portions 20 of the terminal leads 18-1 and 18-2 are exposed, solder can be attached to the bent portions 20, and the connection strength of the capacitor 2 can be increased, for example. The vibration resistance of the capacitor 2 can be improved.

(4) The protrusions 38-1, 38-2 and the shielding part 30 surround the insertion holes 36-1, 36-2 and the through-hole 28, respectively, and the protrusions 38-1, 38-2 and the shielding part 30 are mutually connected. far away. Therefore, in the resin 60 injection step, the injected resin 60 can move relatively freely within the gap. Since the resin 60 passes through the gap between the protrusions 38-1 and 38-2, for example, the pressure of the resin 60 that tries to enter the gap between the protrusions 38-1 and 38-2 and the sealing member 16 is reduced. This prevents the resin 60 from entering the insertion holes 36-1 and 36-2. By installing shields such as the protrusions 38-1 and 38-2 and the shield 30, leakage of the resin 60 can be suppressed.

Features, advantages, modifications, etc. of the embodiments are listed below.

(1) The materials of the capacitor body 4, pedestal 6, and resin layer 8 are not limited to the materials described in the embodiment. These materials may be other materials employed in electrolytic capacitors, electric double layer capacitors, or similar capacitors. Although the capacitor 2 of the embodiment is an electrolytic capacitor formed by impregnating the capacitor element 14 with an electrolytic solution, the capacitor 2 is not limited to an electrolytic capacitor. The capacitor 2 may be a solid electrolytic capacitor having a solid electrolyte layer formed by impregnating the capacitor element 14 with a conductive polymer, or may be formed by impregnating the capacitor element 14 impregnated with a conductive polymer with an electrolytic solution. A hybrid capacitor may also be used.

(2) In the above embodiment, the bent portion 20 is exposed. However, the bent portion 20 may be buried in the resin layer 8. Regardless of whether the bent portion 20 is exposed or buried, the area covered by the resin layer 8 over the surface of the sealing member 16 can be increased, and the sealing performance of the capacitor 2 can be improved.

(3) The shielding distance L1 of the shielding part 30 in the first region 46 may be the same as or smaller than the shielding distance L2 of the shielding part 30 in the second region 48. The width W1 of the stepped portion 52 may be the same as or smaller than the width W2. Further, the stepped portions 52 of the insertion holes 36-1 and 36-2 may be relatively distant from the bent portion 20, and the height H of the small hole portion 54 may be low. The resin layer 8 does not have to extend between the protrusions 38-1, 38-2 and the sealing member 16. The pedestal 6 does not need to include the step 39. If the resin layer 8 extends over at least a portion of the gap between the top surface 30-1 and the sealing member 16, the area covered by the resin layer 8 on the surface of the sealing member 16 can be increased, and the sealing of the capacitor 2 can be improved. You can improve your sexuality. The insertion holes 36-1 and 36-2 may have a plurality of stepped portions 52 formed in a step-like manner.

(4) The shapes of the protruding parts 38-1, 38-2 and the shielding part 30 are not limited to the shapes described above, and may be changed as appropriate. For example, the grooves 50 of the protrusions 38-1 and 38-2 may be provided as necessary. In the shielding part 30, the shielding part 30 in the first region 46 may be thicker than the shielding part 30 in the second region 48, and the shielding distance L1 may be longer than the shielding distance L2 due to the difference in thickness. That is, in the embodiment, although the lid portion 30-3 overlaps the through hole 28, the shielding portion 30 corresponding to the lid portion 30-3 extends to the board mounting surface of the pedestal 6, and shields the first region 46. The portion 30 may be thicker. In this case, the increase in thickness from the shielding part 30 in the second region 48 corresponds to the lid part 30-3, and the size of the part corresponding to the lid part 30-3 is determined based on the appropriate range of the shielding rate described above. The height may be adjusted.

(5) In the embodiment described above, the resin 60 finally reaches the separation part 30-2 and enters the through hole 28. However, before the resin 60 that has reached the separation part 30-2 enters the through hole 28, the resin 60 that has passed over the shielding part 30 may partially fill the through hole 28. Since the shielding part 30 suppresses the amount of resin 60 that exceeds the shielding part 30, the resin 60 that has reached the separation part 30-2 can finally fill the through hole 28, and the through hole 28 can finally be filled. The injection of resin 60 can be stopped after the injection is completed.

As explained above, the most preferred embodiment of the present disclosure has been described, but the technology of the present disclosure is not limited to the above description, and the technology of the present disclosure is not limited to the above description, and the technology of the present disclosure is not limited to the above description. It goes without saying that those skilled in the art can make various modifications and changes based on the gist of the disclosure, and it goes without saying that such modifications and changes are included within the scope of the present disclosure.

The technology of the present disclosure can be widely used in electronic devices and is useful.

2 Capacitor 4 Capacitor body 6 Pedestal 8 Resin layer 12 Exterior case 14 Capacitor element 16 Sealing member 18-1, 18-2 Terminal lead 20 Bent part 22 Exposed terminal part 24-1, 24-2, 36-1, 36- 2 Insertion hole 26 Resin injection hole 28 Through hole 30 Shielding part 30-1 Top surface 30-2 Separation part 30-3

Cover part

32, 34, 52 Step part 38-1, 38-2 Projection part 39 Step 40-1, 40-2 Guide groove 42 Support part 44 Peripheral wall 46 First region 48 Second region 50 Groove part 54 Small hole part 56 Large hole part 57 Inclined surface 58 Resin discharge part 60 Resin

Claims

a capacitor body including an outer case, a sealing member attached to an opening of the outer case, and a plurality of terminal leads protruding from the sealing member;
a plurality of insertion holes installed on the sealing member side of the capacitor body, through which the plurality of terminal leads are inserted, a plurality of protrusions each surrounding the plurality of insertion holes, and a resin injection hole used for injection of resin. a pedestal including a through hole used for checking the injected resin, and a shielding part surrounding the through hole;
a resin layer disposed between the pedestal and the sealing member;
Equipped with
A capacitor, wherein the resin layer extends in at least a portion of the gap between the sealing member and the top surface of the shielding part.
The shielding distance of the shielding part in the first region is longer than the shielding distance of the shielding part in the second region,
The first region is defined as a region between the resin injection hole and the through hole and the region overlapping the through hole, and the second region is defined as a region other than the first region. A capacitor according to claim 1.
3. The shielding part has a lid part that covers the through hole, and the lid part makes a shielding distance in the first area longer than a shielding distance in the second area. capacitor.
The shielding portion has a separation portion on a center line passing through the center of the resin injection hole and the center of the through hole and on the peripheral side of the pedestal,
The minimum cross-sectional area of any one of the plurality of insertion holes, or the minimum cross-sectional area of the gap between the insertion hole and the terminal lead inserted into the insertion hole, is surrounded by the top surface of the shielding part. 4. The capacitor according to claim 1, wherein the capacitor is smaller than the total area of the top opening area formed by the spacer and the side opening area formed by the spacer.
Each terminal lead is bent at the bend,
According to any one of claims 1 to 3, each insertion hole has a stepped portion at a position closer to the sealing member than the bent portion and adjacent to the bent portion. capacitor.
Each insertion hole includes a small hole portion disposed closer to the sealing member than the step portion, and a large hole portion in which the bent portion is disposed,
The resin layer extends over at least a portion of the small hole,
6. The capacitor according to claim 5, wherein the bent portion is exposed without contacting the resin layer.
producing or preparing a capacitor body including an outer case, a sealing member attached to an opening of the outer case, and a plurality of terminal leads protruding from the sealing member;
A plurality of insertion holes, a plurality of protrusions each surrounding the plurality of insertion holes, a resin injection hole used for injecting resin, a through hole used for checking the injected resin, and a plurality of protrusions surrounding the through hole. a step of producing or preparing a pedestal including a shielding part;
installing the pedestal on the sealing member side of the capacitor body, and inserting the plurality of terminal leads into the plurality of insertion holes, respectively;
The resin is injected through the resin injection hole to form a resin layer between the base and the sealing member, and the resin layer is formed in at least a part of the gap between the sealing member and the top surface of the shielding part. a step of extending the
A method for manufacturing a capacitor, comprising: