U.S. patent application number 12/851993 was filed with the patent office on 2011-03-03 for solid electrolytic capacitor and a method for manufacturing the same.
This patent application is currently assigned to SANYO ELECTRIC CO., LTD.. Invention is credited to Hayatoshi Ihara.
Application Number | 20110051324 12/851993 |
Document ID | / |
Family ID | 43624588 |
Filed Date | 2011-03-03 |
United States Patent
Application |
20110051324 |
Kind Code |
A1 |
Ihara; Hayatoshi |
March 3, 2011 |
SOLID ELECTROLYTIC CAPACITOR AND A METHOD FOR MANUFACTURING THE
SAME
Abstract
A solid electrolytic capacitor according to the present
invention includes a solid electrolyte type capacitor element
including a dielectric layer intervening between an anode section
and a cathode section, an anode terminal connected electrically to
the anode section of the capacitor element through a pad member,
and a cathode terminal connected electrically to the cathode
section of the capacitor element. Here, the pad member is formed by
performing a cutting process on a metal plate. The pad member
includes a cutting surface produced by the cutting process, and the
cutting surface forms a joint surface joined to the anode section
of the capacitor element and a joint surface joined to the anode
terminal.
Inventors: |
Ihara; Hayatoshi;
(Kyotanabe-shi, JP) |
Assignee: |
SANYO ELECTRIC CO., LTD.
Osaka
JP
|
Family ID: |
43624588 |
Appl. No.: |
12/851993 |
Filed: |
August 6, 2010 |
Current U.S.
Class: |
361/540 ;
29/25.03 |
Current CPC
Class: |
H01G 9/012 20130101;
Y10T 29/43 20150115; H01G 13/06 20130101 |
Class at
Publication: |
361/540 ;
29/25.03 |
International
Class: |
H01G 9/00 20060101
H01G009/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 27, 2009 |
JP |
2009-196269 |
Claims
1. A solid electrolytic capacitor comprising: a solid electrolyte
type capacitor element including a dielectric layer intervening
between an anode section and a cathode section; an anode terminal
connected electrically to the anode section of the capacitor
element through a pad member; and a cathode terminal connected
electrically to the cathode section of the capacitor element,
wherein the pad member is formed by performing a cutting process on
a metal plate, and which includes a cutting surface produced by the
cutting process, and the cutting surface forms a joint surface
joined to the anode section of the capacitor element and a joint
surface joined to the anode terminal.
2. The solid electrolytic capacitor according to claim 1, wherein
the pad member is formed by performing a punching process on the
metal plate to form a ladder plate member, and thereafter cutting a
rung section out from the ladder plate member, the pad member
includes a pair of cutting surfaces produced by the punching
process, and the cutting surfaces form a joint surface joined to
the anode section of the capacitor element and a joint surface
joined to the anode terminal respectively.
3. The solid electrolytic capacitor according to claim 1, wherein a
width of the pad member in a direction from the anode terminal
toward the cathode terminal is smaller than a height of the pad
member.
4. A method for manufacturing a solid electrolytic capacitor
comprising: a solid electrolyte type capacitor element including a
dielectric layer intervening between an anode section and a cathode
section; an anode terminal connected electrically to the anode
section of the capacitor element through a pad member; and a
cathode terminal connected electrically to the cathode section of
the capacitor element, the method comprising the steps of: forming
a pad forming member which is to be the pad member by performing a
cutting process on a metal plate, the pad forming member having a
width in a direction perpendicular to a thickness direction of the
plate equal to a height of the pad member; joining the pad forming
member to a surface of the anode terminal with its width direction
directed in a direction perpendicular to the surface of the anode
terminal, after performing the forming step; and mounting the
capacitor element on the anode terminal and the cathode terminal
after performing the joining step, and thereafter connecting the
anode section of the capacitor element to a tip end surface of the
pad forming member, and connecting the cathode section of the
capacitor element to the cathode terminal.
5. The method for manufacturing a solid electrolytic capacitor
according to claim 4, wherein in the forming step, the pad forming
member is formed by performing a punching process on the metal
plate to form a ladder plate member, and thereafter cutting a rung
section out from the ladder plate member.
6. The method for manufacturing a solid electrolytic capacitor
according to claim 4, wherein the pad forming member produced in
the forming step has a thickness smaller than the width, and in the
joining step, the pad forming member is joined to the surface of
the anode terminal with its width direction directed in a direction
perpendicular to the surface of the anode terminal and its
thickness direction directed in a direction from the anode terminal
toward the cathode terminal.
Description
[0001] The Japanese application Number 2009-196269, upon which this
patent application is based, is hereby incorporated by
reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a solid electrolytic
capacitor and a method for manufacturing same, and particularly to
a solid electrolytic capacitor in which an anode section of a
capacitor element is electrically connected to an anode terminal
through a pad member and a method for manufacturing same.
[0004] 2. Description of Related Art
[0005] FIG. 9 is a cross sectional view of a conventional solid
electrolytic capacitor. As shown in FIG. 9, the conventional solid
electrolytic capacitor comprises a solid electrolyte type capacitor
element 100, an anode terminal 111, and a cathode terminal 112,
which are buried in an enclosure resin 120. The capacitor element
100 has an anode body 101 in which an anode lead 102 is planted, a
dielectric layer 103 formed on a surface of the anode body 101, an
electrolyte layer 104 formed on the dielectric layer 103, and a
cathode layer 105 formed on the electrolyte layer 104.
[0006] The anode terminal 111 and the cathode terminal 112 include
an anode terminal surface 115 and a cathode terminal surface 116,
respectively, which are exposed on a lower surface 120a of the
enclosure resin 120. To a surface of the anode terminal 111 on the
opposite side to the anode terminal surface 115, joined
electrically is a pad member 114 by welding means such as laser
welding. A tip end part 102a of the anode lead 102 of the capacitor
element 100 is electrically connected to a tip end part of the pad
member 114. To a surface of the cathode terminal 112 on the
opposite side to the cathode terminal surface 116, electrically
connected is a part of a surface of the cathode layer 105 of the
capacitor element 100. The pad member has a rectangular
parallelepiped shape or columnar shape.
[0007] Conventionally, the rectangular parallelepiped pad member
114 is made by, as shown in FIGS. 10a and 10b, performing a
punching process on a metal plate 140 which has a thickness tc
equal to a height hc (cf. FIG. 9) of the pad member 114 to form a
ladder plate member 141, and thereafter cutting the ladder plate
member 141 along the line G-G and the line H-H to cut out a rung
section 142.
[0008] However, in the conventional solid electrolytic capacitor,
the rung section 142 (the pad member) is joined to the surface of
the anode terminal 111 with its thickness direction directed in a
direction perpendicular to the surface of the anode terminal 111.
Therefore, the thickness tc of the metal plate 140 corresponds to
the height hc of the pad member 114 of the capacitor element.
Accordingly, in order to change the height hc of the pad member
114, the thickness tc of the plate 140 to be prepared must be
changed, and thus the height hc of the pad member 114 cannot be
changed easily.
[0009] In the pad member 114 which is joined to the surface of the
anode terminal 111 as described above, all side surfaces of the pad
member 114 are formed by cutting surfaces produced by the punching
process and the cutting out of the rung section 142. Thus the joint
surface of the pad member 114 joined to the anode terminal 111 and
the joint surface of the pad member 114 joined to the anode lead
102 are not formed by the cutting surfaces.
SUMMARY OF THE INVENTION
[0010] In view of the above described problems, an object of the
present invention is to provide a solid electrolytic capacitor in
which the height of the pad member can be changed easily and a
method for manufacturing same.
[0011] A first solid electrolytic capacitor according to the
present invention comprises a solid electrolyte type capacitor
element including a dielectric layer intervening between an anode
section and a cathode section, an anode terminal connected
electrically to the anode section of the capacitor element through
a pad member, and a cathode terminal connected electrically to the
cathode section of the capacitor element.
[0012] Here, the pad member is formed by performing a cutting
process on a metal plate. The pad member includes a cutting surface
produced by the cutting process, and the cutting surface forms a
joint surface joined to the anode section of the capacitor element
and a joint surface joined to the anode terminal.
[0013] The pad member of the first solid electrolytic capacitor
described above is formed by performing the cutting process on the
metal plate to form a pad forming member having a width equal to a
height of the pad member, and thereafter joining the pad forming
member to a surface of the anode terminal with its width direction
directed in a direction perpendicular to the surface of the anode
terminal. Therefore, the width of the pad forming member
corresponds to a height of the pad member of the solid electrolytic
capacitor. The pad member thus formed has a cutting surface which
is produced by the cutting process, and a partial area of the
cutting surface is joined to the surface of the anode terminal.
Also, another area of the cutting surface positioned on the
opposite side to the partial area forms a joint surface joined to
the anode section of the capacitor element.
[0014] Accordingly, the height of the pad member can be changed
only by changing the width of the pad forming member which is
produced from the metal plate, and it is not necessary to change
the thickness of the metal plate. Therefore, in the first solid
electrolytic capacitor described above, a height of the pad member
can be changed easily, compared to the conventional solid
electrolytic capacitor in which it is necessary to change the
thickness of the metal plate in order to change the height of the
pad member.
[0015] A second solid electrolytic capacitor according to the
present invention is the first solid electrolytic capacitor
described above, wherein the pad member is formed by performing a
punching process on the metal plate to form a ladder plate member,
and thereafter cutting a rung section out from the ladder plate
member, the pad member includes a pair of cutting surfaces produced
by the punching process, and the cutting surfaces form a joint
surface joined to the anode section of the capacitor element and a
joint surface joined to the anode terminal respectively.
[0016] A third solid electrolytic capacitor according to the
present invention is the first or second solid electrolytic
capacitor described above, wherein a width of the pad member in a
direction from the anode terminal toward the cathode terminal is
smaller than a height of the pad member.
[0017] In the third solid electrolytic capacitor described above,
since the width of the pad member is small, a space factor of the
capacitor element improves in the solid electrolytic capacitor.
[0018] A first method for manufacturing a solid electrolytic
capacitor according to the present invention comprises a forming
step, a joining step, and a mounting step. Here, the solid
electrolytic capacitor comprises a solid electrolyte type capacitor
element including a dielectric layer intervening between an anode
section and a cathode section, an anode terminal connected
electrically to the anode section of the capacitor element through
a pad member, and a cathode terminal connected electrically to the
cathode section of the capacitor element.
[0019] In the forming step, a cutting process is performed on a
metal plate to form a pad forming member which is to be the pad
member. Here the pad forming member has a width in a direction
perpendicular to a thickness direction of the plate equal to a
height of the pad member.
[0020] In the joining step, after performing the forming step, the
pad forming member is joined to a surface of the anode terminal
with its width direction directed in a direction perpendicular to
the surface of the anode terminal.
[0021] In the mounting step, after performing the joining step, the
capacitor element is mounted on the anode terminal and the cathode
terminal, the anode section of the capacitor element is connected
to a tip end surface of the pad forming member, and the cathode
section of the capacitor element is connected to the cathode
terminal.
[0022] According to the first manufacturing method described above,
the width of the pad forming member corresponds to a height of the
pad member of the manufactured solid electrolytic capacitor.
Accordingly, the height of the pad member can be changed only by
changing the width of the pad forming member which is produced from
the metal plate, and it is not necessary to change the thickness of
the metal plate. Therefore, a height of the pad member can be
changed easily, compared to the conventional solid electrolytic
capacitor in which it is necessary to change the thickness of the
metal plate in order to change the height of the pad member.
[0023] A second method for manufacturing a solid electrolytic
capacitor according to the present invention is the first
manufacturing method described above, wherein in the forming step,
the pad forming member is formed by performing a punching process
on the metal plate to form a ladder plate member, and thereafter
cutting a rung section out from the ladder plate member.
[0024] A third method for manufacturing a solid electrolytic
capacitor according to the present invention is the first or second
manufacturing method described above, wherein the pad forming
member produced in the forming step has a thickness smaller than
the width, and in the joining step, the pad forming member is
joined to the surface of the anode terminal with its width
direction directed in a direction perpendicular to the surface of
the anode terminal and its thickness direction directed in a
direction from the anode terminal toward the cathode terminal.
[0025] According to the third manufacturing method described above,
the thickness and the width of the pad forming member correspond,
respectively, to the width in a direction from the anode terminal
toward the cathode terminal and the height of the pad member of the
manufactured solid electrolytic capacitor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 is a cross sectional view showing a solid
electrolytic capacitor in accordance with an embodiment of the
present invention;
[0027] FIG. 2 is a cross sectional view showing an essential part
of the solid electrolytic capacitor in an enlarged manner;
[0028] FIG. 3a is a plan view for explaining a pad forming step of
a manufacturing method of the solid electrolytic capacitor;
[0029] FIG. 3b is a cross sectional view taken along the line A-A
shown in FIG. 3a;
[0030] FIG. 3c is a perspective view showing a pad formation member
produced in the pad forming step;
[0031] FIG. 4 is a perspective view for explaining a first phase of
a joining step of the manufacturing;
[0032] FIG. 5 is a cross sectional view for explaining a latter
phase of the joining step;
[0033] FIG. 6 is a cross sectional view for explaining a mounting
step of the manufacturing method;
[0034] FIG. 7 is a cross sectional view for explaining an enclosure
resin forming step and a cutting step of the manufacturing
method;
[0035] FIG. 8 is a cross sectional view showing a modification of
the solid electrolytic capacitor;
[0036] FIG. 9 is a cross sectional view showing a conventional
solid electrolytic capacitor;
[0037] FIG. 10a is a plan view for explaining a step of producing a
pad member of the conventional solid electrolytic capacitor;
and
[0038] FIG. 10b is a cross sectional view taken along the line B-B
shown in FIG. 10a.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0039] A preferred embodiment of the present invention is discussed
in detail below with reference to drawings.
[0040] FIG. 1 is a cross sectional view showing a solid
electrolytic capacitor in accordance with an embodiment of the
present invention. As shown in FIG. 1, the solid electrolytic
capacitor of this embodiment comprises a capacitor element 1, an
anode terminal 3, and a cathode terminal 4, which are buried in an
enclosure resin 2. The capacitor element 1 is lead type and
electrolyte type.
[0041] The capacitor element 1 has an anode body 11 in which an
anode lead 12 is planted, a dielectric layer 13 formed on a surface
of the anode body 11, an electrolyte layer 14 formed on the
dielectric layer 13, and a cathode layer 15 formed on the
electrolyte layer 14.
[0042] The anode body 11 is formed by a porous sintered body made
of a valve metal, for which employed is a metal such as tantalum,
niobium, titanium, or aluminum.
[0043] The anode lead 12 includes a base end part 122 buried in the
anode body 11, and a tip end part 121 extracted from a surface of
the anode body 11. The anode lead 12 is made of a valve metal which
is the same kind as or different kind from the valve metal which
forms the anode body 11, and the anode body 11 and the anode lead
12 are electrically connected to each other.
[0044] The dielectric layer 13 is an oxide film formed on the
surface of the anode body 11, and the oxide layer is formed by
immersing the anode body 11 in an electrolytic solution such as
phosphate aqueous solution or adipic acid aqueous solution to
oxidize the surface of the anode body 11 electrochemically (anodic
oxidation).
[0045] The electrolyte layer 14 is formed on the dielectric layer
13, using an electrically-conductive inorganic material such as
manganese dioxide, or an electrically-conductive organic material
such as TCNQ (Tetracyano-quinodimethane) complex salt or
electrically-conductive polymer.
[0046] The cathode layer 15 is formed by a carbon layer (not shown)
formed on the electrolyte layer 14 and a silver paste layer (not
shown) formed on the carbon layer, and the electrolyte layer 14 and
the cathode layer 15 are electrically connected to each other.
[0047] In the capacitor element 1 described above, the anode body
11 and the anode lead 12 form an anode section of the capacitor
element 1, while the electrolyte layer 14 and the cathode layer 15
form a cathode section of the capacitor element 1.
[0048] The anode terminal 3 and the cathode terminal 4 include an
anode terminal surface 31 and a cathode terminal surface 41,
respectively, which are exposed from a lower surface 2a of the
enclosure resin 2. The anode terminal surface 31 and the cathode
terminal surface 41 form a pair of lower surface electrodes of the
solid electrolytic capacitor.
[0049] The anode terminal 3 and the cathode terminal 4 are each
formed by performing a plating process on a surface of a terminal
forming member (not shown) which is made of copper and is a base
material of the terminals to form a plating layer (not shown)
including a nickel layer, a palladium layer, and a gold layer.
Various metals other than copper can be used as a material of the
terminal forming member. Also, various metals other than nickel,
palladium, and gold can be used as a material of the plating
layer.
[0050] A pad member 33 is joined electrically to a surface 32 of
the anode terminal 3 on the opposite side to the anode terminal
surface 31 by welding means such as laser welding. Specifically, by
performing laser welding or the like on facing surfaces of the pad
member 33 and the anode terminal 3, a part of the plating layer of
the anode terminal 3 and a part of the pad member 33 are melted and
integrated, whereby joining the pad member 33 and the anode
terminal 3 to each other electrically. The pad member 33 is formed
using a metal such as iron (42 alloy), nickel, or tantalum.
[0051] The pad member 33 is formed by performing a punching process
on a metal plate 60 to form a ladder plate member 6 (cf. FIG. 3a),
and thereafter cutting a rung section 61 out from the ladder plate
member 6. As shown in FIG. 2, the pad member 33 includes a pair of
cutting surfaces Cs, Cs produced by the punching process, and the
cutting surfaces Cs, Cs form a joint surface (a tip end surface 33a
of the pad member 33) joined to the tip end part 121 of the anode
lead 12 of the capacitor element 1 and a joint surface joined to
the anode terminal 3 respectively.
[0052] Also, in the solid electrolytic capacitor of this embodiment
shown in FIGS. 1 and 2, a width wp of the pad member 33 in a
direction from the anode terminal 3 toward the cathode terminal 4
is smaller than a height hp of the pad member 33.
[0053] As shown in FIG. 1, the capacitor element 1 is mounted on
the anode terminal 3 and the cathode terminal 4. The tip end part
121 of the anode lead 12 of the capacitor element 1 is adhered to
the tip end surface 33a of the pad member 33 by laser welding, and
a part of a surface of the cathode layer 15 is bonded by a
conductive adhesive to a surface 42 of the cathode terminal 4 on
the opposite side to the cathode terminal surface 41. Thereby, the
anode section of the capacitor element 1 is electrically connected
to the anode terminal 3 through the pad member 33, and the cathode
section of the capacitor element 1 is electrically connected to the
cathode terminal 4 through the conductive adhesive.
[0054] A manufacturing method of the above described solid
electrolytic capacitor is explained below.
[0055] FIG. 3a is a plan view for explaining the pad forming step
of the manufacturing method of the solid electrolytic capacitor,
FIG. 3b is a cross sectional view taken along the line A-A shown in
FIG. 3a, and FIG. 3c is a perspective view showing a pad formation
member produced in the pad forming step.
[0056] As shown in FIGS. 3a and 3b, in the pad forming step, the
metal plate 60 is subjected to the punching process to form a
plurality of punched apertures 601 which is aligned in a row.
Thereby, a ladder plate member 6 is formed, and the ladder plate
member 6 includes a plurality of rung sections 61. The metal plate
60 is made of a metal such as iron (42 alloy), nickel, or
tantalum.
[0057] The processing conditions of the punching process are set so
that a length x0 of the rung section 61 is equal to the height hp
(cf. FIG. 2) of the pad member 33. Here, the length x0 is a length
of the rung section 61 in the longitudinal direction of the ladder
plate member 6 to be produced in the punching process, namely in a
direction from one of adjacent punched apertures 601, 601 toward
the other.
[0058] In the manufacturing method in accordance with this
embodiment, employed for the metal plate 60 is a plate having a
thickness t0 smaller than the length x0 of the rung section 61.
[0059] After forming the ladder plate member 6, the ladder plate
member 6 is cut along the lines E-E and F-F to cut out the rung
section 61 as shown in FIG. 3a, thereby forming a pad forming
member 62 which is to be the pad member 33 as shown in FIG. 3c. In
this process, each of the rung sections 61 is fastened by a
fastening apparatus (not shown) while its both ends are cut off,
and therefore, the produced pad forming member 62 is kept fastened
by the fastening apparatus.
[0060] By forming the pad forming member 62 in such a manner, as
shown in FIG. 3c, the length x0 of the rung section 61 and the
thickness t0 of the plate 60 correspond to a width wp0 and a
thickness tp0 of the pad forming member 62, respectively.
Therefore, the pad forming member 62 has a width equal to the
height hp of the pad member 33, and a thickness smaller than the
width.
[0061] FIG. 4 is a perspective view for explaining a first phase of
a joining step of the manufacturing method of the solid
electrolytic capacitor, and FIG. 5 is a cross sectional view for
explaining a latter phase of the joining step. The joining step is
performed after performing the pad forming step.
[0062] As shown in FIG. 4, in the first phase of the joining step,
the pad forming member 62 is rotated by 90 degrees to change the
posture of the pad forming member 62 so that the right and left
pair of cutting surfaces Cs, Cs faces upward and downward. Here,
the pair of cutting surfaces Cs, Cs is produced by the punching
process in the pad forming step.
[0063] As shown in FIG. 5, in the latter phase of the joining step,
a frame body 5 is prepared, and the frame body 5 has an anode frame
51 which is to be the anode terminal 3 and a cathode frame 52 which
is to be the cathode terminal 4. The pad forming member 62 whose
posture has been changed is placed on an upper surface 512 of the
anode frame 51 of the frame body 5 with the pair of cutting
surfaces Cs, Cs facing upward and downward.
[0064] Specifically, a table (not shown) is prepared. The table can
make the pad forming member 62 stick to its surface and can change
its own posture. The pad forming member 62 fastened by the
fastening apparatus is transported to the table, while maintaining
the posture taken immediately after the formation of the pad
forming member 62 (the posture taken when the rung sections 61 are
cut), and then placed on the surface of the table while maintaining
the posture. After the pad forming member 62 is made to stick to
the surface of the table, the pad forming member 62 is released
from being fastened by the fastening apparatus. Thereafter, by
changing the posture of the table, the posture of the pad forming
member 62 is changed as shown in FIG. 4.
[0065] Subsequently, the pad forming member 62 whose posture has
been changed is again fastened by the fastening apparatus, and
thereafter the pad forming member 62 is made to stop sticking to
the surface of the table. Thereafter, the pad forming member 62 is
transported to the anode frame 51, while maintaining the changed
posture, and then placed on the upper surface 512 of the anode
frame 51 while maintaining the changed posture.
[0066] The pad forming member 62 is thus placed on the upper
surface 512 of the anode frame 51 with its width direction 621
directed in a direction perpendicular to the upper surface 512 of
the anode frame 51 and its thickness direction 622 directed in a
direction from the anode frame 51 toward the cathode frame 52, as
shown in FIG. 5 (see also FIGS. 3c and 4).
[0067] The anode frame 51 and the cathode frame 52 are each formed
by performing a plating process on a surface of a frame forming
member (not shown) which is made of copper and is a base material
of the frames to form a plating layer (not shown) including a
nickel layer, a palladium layer, and a gold layer. Various metals
other than copper can be used as a material of the frame forming
member. Also, various metals other than nickel, palladium, and gold
can be used as a material of the plating layer.
[0068] After the pad forming member 62 is placed on the upper
surface 512 of the anode frame 51, laser welding is performed on
facing surfaces between the pad forming member 62 and the anode
frame 51. A part of the plating layer of the anode frame 51 and a
part of the pad forming member 62 are thereby melted and
integrated, and as a result, the pad forming member 62 and the
anode frame 51 are joined to each other electrically.
[0069] By joining the pad forming member 62 to the anode frame 51
as described above, the pad member 33 is formed from the pad
forming member 62. The pad forming member 62 includes the pair of
cutting surfaces Cs, Cs produced by the punching process in the pad
forming step, and the cutting surfaces Cs, Cs form the joint
surface of the pad member 33 joined to the anode frame 51, and a
tip end surface 33a of the pad member 33 which is a joint surface
joined to the anode lead 12, respectively.
[0070] FIG. 6 is a cross sectional view for explaining a mounting
step of the manufacturing method of the solid electrolytic
capacitor. The mounting step is performed after performing the
joining step. As shown in FIG. 6, in the mounting step, the
capacitor element 1 is mounted on the frame body 5.
[0071] When mounting the capacitor element 1 on the frame body 5,
the tip end part 121 of the anode lead 12 of the capacitor element
1 is brought into contact with a tip end surface 62a of the pad
forming member 62 (the tip end surface 33a of the pad member 33),
and laser welding is performed on the contact surface to fix the
tip end part 121 of the anode lead 12 to the tip end surface 62a of
the pad forming member 62. The anode lead 12 and the pad forming
member 62 are thereby connected to each other electrically.
[0072] Concurrently, a part of the surface of the cathode layer 15
of the capacitor element 1 is bonded to an upper surface 522 of the
cathode frame 52 using a conductive adhesive. The cathode layer 15
and the cathode frame 52 are thereby connected to each other
electrically.
[0073] FIG. 7 is a cross sectional view for explaining an enclosure
resin forming step and a cutting step of the manufacturing method
of the solid electrolytic capacitor. The enclosure resin forming
step is performed after performing the mounting step. As shown in
FIG. 7, in the enclosure resin forming step, the enclosure resin 2
is formed around the capacitor element 1, thereby burying the
capacitor element 1, the pad forming member 62, the anode frame 51
and the cathode frame 52 in the enclosure resin 2. At this time, a
lower surface 511 of the anode frame 51 and a lower surface 521 of
the cathode frame 52 are exposed from a lower surface 2a of the
enclosure resin 2. Thus, a block body 72 is produced in the
enclosure resin forming step.
[0074] The cutting step is performed after performing the enclosure
resin forming step. As shown in FIG. 7, in the cutting step, the
block body 72 produced in the enclosure resin forming step is
subjected to a cutting process. Specifically, the block body 72 is
cut along the line C-C, thereby cutting the enclosure resin 2 and
the anode frame 51 along the same plane. Further, the block body 72
is cut along the line D-D, thereby cutting the enclosure resin 2
and the cathode frame 52 along the same plane.
[0075] By performing the cutting step, respective parts of the
anode frame 51 and the cathode frame 52 are cut off to form the
anode terminal 3 and the cathode terminal 4, and thereby the
capacitor element 1 is formed as shown in FIG. 1.
[0076] In the manufacturing method described above, the pad forming
member 62 is joined to the upper surface 512 of the anode frame 51
with its width direction 621 directed in the direction
perpendicular to the upper surface 512 of the anode frame 51.
Therefore, the width wp0 of the pad forming member 62 corresponds
to the height hp of the pad member 33 of the produced solid
electrolytic capacitor. Accordingly, the height hp of the pad
member 33 can be changed only by changing the width wp0 of the pad
forming member 62 which is produced from the metal plate 60, and it
is not necessary to change the thickness t0 of the metal plate
60.
[0077] Therefore, in the solid electrolytic capacitor of this
embodiment and its manufacturing method, the height of the pad
member 33 can be changed easily, compared to the conventional solid
electrolytic capacitor in which it is necessary to change the
thickness tc of the metal plate 140 (cf. FIG. 10b) in order to
change the height hc of the pad member 114 as shown in FIG. 9.
[0078] Further, in the manufacturing method described above, the
pad forming member 62 is joined to the upper surface 512 of the
anode frame 51 with its thickness direction 622 directed in the
direction from the anode frame 51 toward the cathode frame 52.
Therefore, the thickness tp0 of the pad forming member 62
corresponds to the width wp of the pad member 33 of the
manufactured solid electrolytic capacitor in a direction from the
anode terminal 3 to the cathode terminal 4. Here, in the
manufacturing method described above, the pad forming member 62
produced therein has the thickness tp0 which is smaller than the
width wp0. Accordingly, in the manufactured solid electrolytic
capacitor, the width wp of the pad member is small and the space
factor of the capacitor element 1 improves.
[0079] The present invention is not limited to the foregoing
embodiment in construction but can be modified variously by one
skilled in the art without departing from the spirit of the
invention as set forth in the appended claims. For example, the
configurations concerning the pad member 33 employed in the above
described solid electrolytic capacitor including the lead type
capacitor element 1 and the manufacturing method thereof can be
applied to a solid electrolytic capacitor including a foil-like
capacitor element 8 as shown in FIG. 8.
[0080] As shown in FIG. 8, in the foil-like capacitor element 8, a
surface of a foil-like anode body 81 includes a first area 811
where a dielectric layer 82 is formed and a second area 812 where
the dielectric layer 82 is not formed. An electrolyte layer 83 is
formed on the dielectric layer 82, and a cathode layer 84 is formed
on the electrolyte layer 83. In the solid electrolytic capacitor
shown in FIG. 8, the tip end surface 33a of the pad member 33 which
is formed by the cutting surface Cs is connected to the second area
812 on the surface of the anode body 81.
[0081] In the above described solid electrolytic capacitor and the
manufacturing method thereof, the pad forming member 62 which is to
be the pad member 33 is formed by performing the punching process
on the metal plate 60 to form the ladder plate member 6, and
thereafter cutting the rung section 61 out from the ladder plate
member 6. However, the present invention is not limited to this.
The pad forming member 62 may be formed by performing various
cutting processes on the metal plate 60.
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