JP2000307209A - Joint box - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce cost by facilitating assembly. SOLUTION: This joint box has a plurality of connecting terminals 141 having bending parts 145 capable of elastic deformation at the tips. In an electric circuit unit 16, a printed circuit board 161 has a plurality of through holes 163. The bending parts 145 of the connecting terminals 141 are inserted in the through holes 163 and pressure-welded to a conductor film 166 in the state of elastic deformation. As a result, a wiring unit 14 and an electronic circuit unit 16 are electrically connected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a joint box in which an electronic circuit unit is mounted on a wiring unit housed inside a case.

[0002]

2. Description of the Related Art Conventionally, this type of joint box has
The wiring unit and the electronic circuit unit are electrically connected, for example, in a configuration as shown in FIG. That is,
A plurality of male terminals 103 are formed on the bus bar board 102 constituting the wiring unit 101 so as to protrude toward the electronic circuit unit 104 in a state of being arranged in a line, while the circuit board 105 constituting the electronic circuit unit 104 has A connector 109 having a plurality of U-shaped connector terminals 107 having a female terminal 106 at one end is mounted in a housing 108, and a plurality of through holes 110 through which the male terminals 103 are inserted and the connector terminals 107. Are formed in a state where a plurality of through-holes 111 through which are inserted are respectively arranged in a line, and the male terminals 103 of the wiring unit 101 are inserted through the through-holes 110 of the electronic circuit unit 104 so as to be inserted into the female terminals 106 of the connector 109. By being fitted, the electrical connection between the wiring unit 101 and the electronic circuit unit 104 is established. It is to be carried out (JP-A-9-9457).

[0003]

In the above-mentioned conventional joint box, it is necessary to attach a connector 109 to a circuit board 105 constituting the electronic circuit unit 104.
For this reason, there has been a problem that the number of components increases, and the mounting work is required, which leads to an increase in the cost of the joint box.

As shown in FIG. 8, a circuit board 112 is provided.
A technique has been proposed in which the branch terminals 115 of the connection terminals 114 soldered to the conductive pattern 113 are soldered to the conductive pattern 117 of another circuit board 116 to electrically connect the two circuit boards 112 and 116. (Japanese Unexamined Patent Publication No. 7-22091), it is conceivable that such a technique is applied to a joint box so that the connector 109 is not used. However, in this case, although the connector 109 becomes unnecessary, the two circuit boards 11 are not necessary.
Since the soldering work is required to electrically connect the components 2 and 116, the efficiency of the assembling operation is reduced, so that the cost of the joint box cannot be avoided.

Further, as shown in FIG.
A land 120 is formed on the periphery of the connection hole 119 formed in the connector, and a female independent terminal 122 having an elastic holding portion 121 formed therein is fitted into the connection hole 119.
1 by holding the tab terminal 123 therebetween.
There has been proposed a technique of electrically connecting the terminal 18 to the tab terminal 123 (Japanese Patent Laid-Open No. 10-199595). Such a technique may be applied to a joint box so that the connector 109 is not used. Conceivable. However, in this case, since the independent terminal 122 has a relatively complicated structure, it is expensive, and since the direction of the independent terminal 122 with respect to the tab terminal 123 needs to be adjusted, the installation work is troublesome. As a result, an increase in the cost of the joint box cannot be avoided.

[0006] The present invention has been made in view of such circumstances, and has as its object to provide a joint box that can be easily assembled and cost reduced.

[0007]

According to a first aspect of the present invention, there is provided a joint box in which an electronic circuit unit is mounted on a wiring unit housed in a case. At least a portion of the peripheral surface includes a plurality of through holes formed of a conductor, and the wiring unit includes a plurality of connection terminals formed with contact portions inserted into the through holes in an elastically deformed state, The wiring unit and the electronic circuit unit are electrically connected by inserting a contact portion into the through hole and pressing the contact portion against the conductor.

According to this structure, the contact portion of the connection terminal of the wiring unit is inserted into the through hole of the electronic circuit unit and pressed against the conductor, so that the wiring unit and the electronic circuit unit are electrically connected. In addition, the connection structure between the two is simplified, the assembling becomes easy, and the cost of the joint box can be reduced.

According to a second aspect of the present invention, in the first aspect, the connection terminal is formed of a metal plate protruding toward the electronic circuit unit, and the contact portion is formed on the metal plate. It is characterized by having a bent portion.

According to this configuration, since the contact portion of the connection terminal can be reliably elastically deformed, the electrical connection between the wiring unit and the electronic circuit unit is reliably performed, and the reliability of the joint box can be improved. .

The invention according to a third aspect is characterized in that, in the second aspect, the bent portion is formed by bending a tip end of the metal plate.

According to this structure, the connection terminals can be easily formed, and the connection terminals can be easily inserted into the through holes.

According to a fourth aspect of the present invention, in the second aspect, the bent portion includes a tip portion of the metal plate,
It is characterized by being formed with a separate metal plate piece attached to the flat surface of the tip.

According to this structure, since the connection terminal is formed by attaching the metal plate piece of another member bent in another process to the flat surface of the front end of the metal plate, the wiring unit can be easily manufactured.

According to a fifth aspect of the present invention, in accordance with the fourth aspect, the upper portion of the metal plate piece is attached to a front end portion of the metal plate, and the lower portion thereof is formed with respect to a plane of the front end portion of the metal plate. It is characterized by being bent in a direction protruding outward.

According to this structure, the connection terminal is formed by attaching the metal plate piece of another member, which is manufactured by bending in another process, to the top of the metal plate at the upper portion thereof, so that the wiring unit can be easily manufactured. Become.

According to a sixth aspect of the present invention, in accordance with the fourth aspect, the lower portion of the metal plate piece is attached to a tip portion of the metal plate, and the upper portion is folded back. .

According to this structure, the connection terminal is formed by attaching a metal plate piece of another member, which is manufactured by folding back in another process, to a lower end portion of the metal plate, thereby facilitating the manufacture of the wiring unit. Become.

According to a seventh aspect of the present invention, in accordance with the second aspect, the bent portion is formed of a separate metal plate piece having a fitting portion fitted to a tip portion of the metal plate. It is characterized by having.

According to this configuration, the connection terminal is formed by fitting the metal plate piece having the bent portion formed in another step to the tip of the metal plate by fitting, thereby facilitating the manufacture of the wiring unit.

According to an eighth aspect of the present invention, in the seventh aspect, the tip of the metal plate piece is folded back.

According to this configuration, since the connection terminal is formed by fitting the metal plate piece folded in another process to the tip of the metal plate by fitting, the wiring unit can be easily manufactured.

Further, the invention of claim 9 provides the invention according to claims 1 to 8
Wherein the wiring unit is formed of a bus bar substrate, and the connection terminals are tab terminals formed by erecting a bus bar of the bus bar substrate.

According to this configuration, the contact portion formed on the tab terminal of the bus bar board is inserted into the through hole of the electronic circuit unit and pressed against the conductor, so that the bus bar board and the electronic circuit unit are electrically connected. Therefore, the connection structure between the two is simplified, the assembling becomes easy, and the cost of the joint box can be reduced.

According to a tenth aspect of the present invention, in any one of the first to ninth aspects, the through hole connects wiring conductors formed on both surfaces of a circuit board constituting the electronic circuit unit. Therefore, it is a through hole formed in the circuit board.

According to this structure, the wiring unit and the electronic circuit unit are electrically connected by inserting the contact portion of the connection terminal into the through-hole and press-contacting the contact portion, so that the through-hole formed for another purpose is formed. Can be effectively used, the assembly becomes easy, and the cost of the joint box can be reduced.

[0027]

FIG. 1 is a sectional view of a main part of a joint box according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the joint box. In these figures, a joint box 10 is provided with a storage case 12.
And the wiring unit 1 stored inside the storage case 12
4 and an electronic circuit unit 16 mounted on the wiring unit 14.

The storage case 12 is composed of a rectangular upper case 121 and a rectangular lower case 122 combined with the upper case 121.
The upper case 121 is made of a synthetic resin,
1a A plurality of connector housings 123 are provided at one end on the outer surface side.
(Only one is shown) is integrally formed with the main wall 12.
A plurality of through holes 124 through which tab terminals are inserted are formed at locations corresponding to the connector housing 123 of FIG. The lower case 122 is made of a synthetic resin,
A plurality of connector housings 125 are integrally formed at one end on the outer surface side of the main wall 122a, and a connector housing 126 to which external wiring is connected is formed at the other end on the outer surface side of the main wall 122a.

In the present embodiment, the wiring unit 14 is formed of a rectangular bus bar substrate in which a plurality of insulating plates made of a synthetic resin and a plurality of bus bars made of a metal plate are alternately laminated, and the main wall of the upper case 121 is formed. It is arranged in contact with 121a. Further, the wiring unit 14 is provided at a position corresponding to the plurality of connection terminals 141 for the electronic circuit unit 16 formed at both ends in the width direction on the one surface side toward the electronic circuit unit 16 and the connector housing 125 on the one surface side. A plurality of connector terminals 142 protrudingly formed
And a plurality of connector terminals 143 protruding at positions corresponding to the connector housing 123 on the other side.

The connection terminal 141 and the connector terminal 1
Reference numerals 42 and 143 denote tab terminals formed by erecting a long metal plate constituting a bus bar, and the connection terminal 141 is elastically deformable at the tip of the long metal plate 144. It has a bent portion 145. The bent portion 145 serves as a contact portion with a through hole 163 to be described later, and includes an upright portion 145a and a folded portion 145b. The folded part 145b is the upright part 1
45a which is folded so as to have an acute angle with respect to 45a
One bent portion 145c and the tip thereof is the first bent portion 145.
and a second bent portion 145d bent inward so as to have an obtuse angle with respect to c. Further, the wiring unit 14 is provided with four bosses 146 for screwing the electronic circuit unit 16 on both sides in the column direction of each connection terminal 141 group at both ends in the width direction on one surface side.

The electronic circuit unit 16 has a structure in which a plurality of electronic components 162 are mounted on a rectangular printed circuit board 161 having predetermined wiring conductors to form a predetermined electronic circuit such as a control circuit. This printed circuit board 1
61, a plurality of through holes 163 are formed in a line at both ends in the width direction.
A screw hole 164 is formed at a position corresponding to the boss 146 of FIG. Each through hole 163 is connected to the printed circuit board 1
A conductor film 166 for connecting upper and lower wiring conductors is formed on the inner peripheral surface of the through hole 165 formed in the through-hole 61, and the bent portion 145 of the connection terminal 141 is inserted into the through-hole 163. The bent portion 145 is formed in such a size that the bent portion 145 is pressed against the conductive film 166 in an elastically deformed state. Further, a plurality of connector terminals 167 are implanted at positions corresponding to the connector housing 126 on the left end side of the printed circuit board 16 in the drawing.

The electronic circuit unit 1 configured as described above
6, the bent portions 145 of the connection terminals 141 are inserted into the through holes 163 as shown in FIG.
5 is elastically deformed and presses against the conductor film 166 of the through hole 163 and the printed circuit board 161 is screwed into the screw hole 164.
Is fixed to the boss 146 with the screw 168 via the.

In the joint box 10 configured as described above, the wiring unit 14 and the electronic circuit unit are formed by simply inserting the bent portion 145 of the connection terminal 141 into the through hole 163 and elastically deforming the connection terminal 141 so as to press against the conductor film 166. 16 can be electrically connected, the assembly becomes easy, and the cost of the joint box can be reduced.

That is, in order to electrically connect the wiring unit 14 and the electronic circuit unit 16, the conventional connector 109 (FIG. 7) and the independent terminal 122 (FIG. 9) having a complicated structure are used.
And the like, and the mounting work thereof is also unnecessary, and the wiring unit 14 and the electronic circuit unit 1 are not required.
Therefore, the cost of the joint box 10 can be reduced since the soldering operation for connecting the terminal 6 and the terminal direction adjusting operation are not required. In addition, the conventional connector 1
Since the components such as the connector 09 and the independent terminal 122 are not required, a space for mounting the components is not required, and the printed circuit board 161 can be downsized. From these points, the cost reduction of the joint box 10 is promoted. can do.

Further, since the bent portion 145 of the connection terminal 141 is pressed against the conductor film 166 of the through hole 163 while being elastically deformed, the wiring unit 14
And the electronic circuit unit 16 are reliably electrically connected, and the joint box 10 having excellent circuit operation reliability can be realized.

In the above embodiment, the connection terminal 141 is used.
The bent portion 145 is formed by directly bending the tip of the upright portion 145a. Instead of the connection terminal 141 having such a configuration, FIG. 4A, FIG. 5A, or FIG. Connection terminals 141a, 141 having the configuration shown in FIG.
b or 141c can be adopted.

The connection terminal 141a shown in FIG.
Is a front end portion 144a of a long metal plate 144, and a separate metal plate piece 1 attached to the plane of the front end portion 144a.
47 and a bent portion 148 are formed. That is, the metal plate piece 147 as a separate member has an attachment portion 147a attached to the top surface of the tip portion 144a of the metal plate 144 at the upper portion, and the attachment portion 147a at the bottom portion protrudes outward from the plane of the tip portion 144a of the metal plate 144. Folded part 147b formed by bending
The mounting portion 147a is integrally attached to the distal end portion 144a of the metal plate 144 by means such as welding or bonding. The bent portion 147b is attached to the mounting portion 147a.
A first bent portion 147c bent at an acute angle with respect to the metal plate 144 in a state where the first bent portion 147c is attached to the metal plate 144, and the tip thereof has an obtuse angle with respect to the first bent portion 147c. And a second bent portion 147d that is bent inward.

The connection terminal 141a having such a configuration
As shown in FIG. 4B, the bent portion 148 is inserted into the through hole 163 of the printed circuit board 161,
The conductive film 166 is pressed against the conductor film 166 while being elastically deformed. Even when such a connection terminal 141a is employed, the same operation and effect as those of the embodiment shown in FIGS. 1 and 2 can be obtained. Further, in such a connection terminal 141a, the metal plate piece 147 can be bent in a separate step, and the metal plate piece 147 processed in this separate step can be attached to the mounting portion 1.
Since it is only necessary to attach the metal plate 144 to the front end portion 144a of the metal plate 144 by using 47a, it is not necessary to perform a complicated operation such as bending the front end portion of the metal plate 144 on the wiring unit 14, and the wiring unit 14 can be easily manufactured.

The connection terminal 141b shown in FIG.
Is a front end portion 144a of a long metal plate 144, and a separate metal plate piece 150 attached to the front end portion 144a.
And the bent portion 151 is formed. That is,
The metal plate piece 150 as a separate member has a mounting portion 150a attached to the tip end portion 144a of the metal plate 144 formed at the lower portion, and a folded portion 150b formed by folding the upper portion thereof. It is integrally attached to the tip 144a of the body 144 by means such as welding or bonding. The folded portion 150b is bent at an acute angle with respect to the metal plate 144 while being attached to the metal plate 144 by the attaching portion 150a.
0c, and a second bent portion 150d whose tip is bent inward so as to have an obtuse angle with respect to the first bent portion 150c.

The connection terminal 141b having such a configuration
As shown in FIG. 5B, the bent portion 151 is inserted into the through hole 163 of the printed circuit board 161 as shown in FIG.
The conductive film 166 is pressed against the conductor film 166 while being elastically deformed. Even when such a connection terminal 141b is employed, the same operation and effect as those of the embodiment shown in FIGS. 1 and 2 can be obtained. Further, in such a connection terminal 141b, the metal plate 150 can be bent in another process, and the metal plate 150 processed in this another process can be attached to the mounting portion 1.
The wiring unit 14 can be easily manufactured because it is not necessary to perform a complicated operation such as bending the front end of the metal plate 144 on the wiring unit 14 since the metal unit 144 can be attached to the front end 144a of the metal plate 144 by 50a.

The connection terminal 141c shown in FIG.
The bent portion 1 is formed by a separate metal plate piece 153 integrally attached to the distal end of the long metal plate 144 by fitting means.
54 are formed. That is, the metal plate piece 153 as a separate member is provided at the lower portion with the fitting portion 15 formed of a pair of opposed plates.
3a, and an extension 153b located on the extension of the metal plate 144 is formed on the upper portion.
A bent portion 153c is formed by bending the distal end of 53b. The fitting portion 153a is fitted to the distal end of the metal plate 144, and is integrally attached by means such as welding or bonding.

The folded portion 153c has a first bent portion 153d which is bent at an acute angle with respect to the extending portion 153b, and a tip thereof has an obtuse angle with the first bent portion 153d. And a second bent portion 153e that is bent inward. In addition, the metal plate piece 153 as another member can be formed by, for example, attaching the end of the extending portion 153b to a fitting portion 153a formed by bending in an inverted U-shape by means such as welding or bonding. .

The connection terminal 141c having such a configuration
6B, the bent portion 154 is inserted into the through hole 163 of the printed circuit board 161 as shown in FIG.
The conductor film 166 is pressed against the conductor film 166 while being elastically deformed. Even when such a connection terminal 141c is adopted,
The same operational effects as those of the embodiment shown in FIGS. 1 and 2 can be obtained. Further, in such a connection terminal 141c,
Since the bent portion 154 manufactured in a separate process is attached to the tip of the metal plate 144 of the wiring unit 14, complicated operations such as bending the tip of the metal plate 144 on the wiring unit 14 are performed. This eliminates the necessity and facilitates the production of the wiring unit 14.

In each of the embodiments, the bent portions 145, 148, 151, and 154 are formed by the second bent portion 145.
c, 147d, 150d, 153e,
Even when the bent portions 145, 148, 151, and 154 are pulled out from the through holes 163, the electronic circuit unit 16 can be easily removed from the wiring unit 14 because the electronic circuit unit 16 is not caught on the conductor film 166. Second bent portions 145c, 147d, 150
d and 153e are not always required.

The bent portions 145, 148, and 1 serving as contact portions with the through holes 163 in the above embodiment.
Instead of 51 and 154, the front end of the metal plate 144 is directly bent into a wave shape to make a contact portion with the through hole 163, or a semicircular convex portion is formed on the flat surface of the front end of the metal plate 144 to form a through hole. It is also possible to use a contact portion for the 163. Even in this case, the contact portion can be elastically deformed and pressed against the through hole 163.

In each of the embodiments, the bent portions 145, 148, 151, and 154 are provided with through holes 1 for connecting wiring conductors on both sides of the printed circuit board 161.
The bent portions 145, 148, 151, and 154 can be inserted into through holes other than the through holes formed in the printed circuit board 161. That is, a conductor film is formed on the inner peripheral surface of the through hole so that at least a part of the through hole is formed of a conductor.
What is necessary is just to connect the wiring conductor formed in 61. The bent portions 145, 148, 151, 154
Is inserted into the through-hole 163, there is no need to separately form a through-hole at least partially formed of a conductor as described above, and thus there is an advantage that the configuration of the printed circuit board 161 is simplified. .

[0047]

As described above, according to the first aspect of the present invention, the electronic circuit unit has a plurality of through holes in which at least a part of the inner peripheral surface is formed of a conductor, and the wiring unit is elastically deformed. A plurality of connection terminals having a contact portion inserted into the through hole are provided, and the contact portion is inserted into the through hole and pressed against a conductor to electrically connect the wiring unit and the electronic circuit unit. As a result, the assembly is facilitated, and the cost of the joint box can be reduced.

According to the second aspect of the present invention, the connection terminal is formed of a metal plate projecting toward the electronic circuit unit, and the contact portion is formed of a bent portion formed on the metal plate.
Since the contact portions surely have elasticity, the reliability of the electrical connection between the wiring unit and the electronic circuit unit can be improved.

According to the third aspect of the present invention, since the bent portion is formed by bending the tip of the metal plate, the connection terminal can be easily formed, and the insertion into the through hole can be easily performed. It can be carried out.

According to the fourth aspect of the present invention, since the bent portion is formed by the tip of the metal plate and the metal plate piece of another member attached to the flat surface of the tip, the bent portion is processed in another step. The wiring unit can be easily manufactured by attaching the metal plate piece to the front end plane of the metal plate.

According to the fifth aspect of the present invention, the metal plate piece is
The upper part is attached to the tip of the metal plate, and the lower part is bent in the direction protruding outward with respect to the plane of the tip of the metal plate. The wiring unit can be easily manufactured by attaching to the partial plane.

In the invention according to claim 6, the metal plate piece is
Since the lower part is attached to the tip of the metal plate and the upper part is folded, the wiring unit can be easily manufactured by attaching the metal plate piece processed in another process to the tip of the metal plate.

According to the seventh aspect of the present invention, since the bent portion is formed by a metal plate piece of a separate member having a fitting portion fitted to the front end portion of the metal plate, the metal processed in another process is formed. The wiring unit can be easily manufactured by fitting the plate piece to the tip of the metal plate by fitting.

According to the eighth aspect of the present invention, since the tip of the metal plate piece is folded back, the connection terminal can be easily formed, and the insertion into the through hole can be easily performed.

According to the ninth aspect of the present invention, the wiring unit is formed of a bus bar substrate, and the connection terminal is a tab terminal formed by erecting the bus bar of the bus bar substrate, so that the connection terminal can be easily formed. .

According to the tenth aspect, the through hole is
Since the through holes are formed to connect the wiring conductors formed on both sides of the circuit board constituting the electronic circuit unit, the configuration of the electronic circuit unit can be simplified.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a joint box according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the joint box shown in FIG.

FIG. 3 is a view for explaining a connection state between a connection terminal and a through hole of the joint box shown in FIG. 1;

4A and 4B are views showing a first modification of the connection terminal of the joint box shown in FIG. 1, wherein FIG.
(B) is a figure which shows the connection state of a connection terminal and a through-hole.

5A and 5B are views showing a second modification of the connection terminal of the joint box shown in FIG. 1, wherein FIG.
(B) is a figure which shows the connection state of a connection terminal and a through-hole.

FIGS. 6A and 6B are views showing a third modification of the connection terminal of the joint box shown in FIG. 1, wherein FIG.
(B) is a figure which shows the connection state of a connection terminal and a through-hole.

FIG. 7 is an exploded perspective view for explaining an electrical connection configuration between a wiring unit and an electronic circuit unit in a conventional example.

FIG. 8 is a perspective view for explaining another electrical connection configuration of the conventional example.

FIG. 9 is a cross-sectional view of a main part for describing another electrical connection configuration of the conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Joint box 12 Storage case 14 Wiring unit 16 Electronic circuit unit 121 Upper case 122 Lower case 141,141a, 141b, 141c Connection terminal 145,148,151,154 Bent part (contact part) 147,150,153 Metal plate piece 151 Fitting part 161 Printed circuit board (circuit board) 163 Through hole

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Koji Kishimoto 1-7-10 Kikuzumi, Minami-ku, Nagoya-shi, Aichi F-term in Harness Research Institute, Inc. (Reference) 5E023 BB16 DD05 EE03 FF07 HH28 5E077 BB01 DD14 EE06 GG04 JJ20 5E344 AA01 BB02 BB06 CC09 CD15 DD07 EE21 5G361 BA04 BB01 BB02 BB03 BC01

Claims (10)

[Claims] 1. A joint box in which an electronic circuit unit is mounted on a wiring unit housed inside a case, wherein the electronic circuit unit has a plurality of through holes formed at least in part of an inner peripheral surface with a conductor. Along with
The wiring unit includes a plurality of connection terminals each having a contact portion that is inserted into the through hole in an elastically deformed state, and the contact portion is inserted into the through hole and pressed against the conductor to form the wiring. A joint box, wherein the unit and the electronic circuit unit are electrically connected. 2. The connection terminal according to claim 1, wherein the connection terminal is formed of a metal plate protruding toward the electronic circuit unit, and the contact portion is formed of a bent portion formed on the metal plate. Joint box. 3. The joint box according to claim 2, wherein the bent portion is formed by bending a front end portion of the metal plate. 4. The method according to claim 1, wherein the bent portion includes a tip portion of the metal plate,
3. The joint box according to claim 2, wherein the joint box is formed by a separate metal plate piece attached to the flat surface of the distal end portion. 5. The metal plate piece has an upper part attached to a tip part of the metal plate and a lower part bent in a direction protruding outward with respect to a plane of the tip part of the metal plate. The joint box according to claim 4, characterized in that: 6. The joint box according to claim 4, wherein the lower part of the metal plate piece is attached to a tip end of the metal plate, and the upper part is folded back. 7. The joint box according to claim 2, wherein the bent portion is formed of a separate metal plate piece having a fitting portion fitted to a tip end of the metal plate. . 8. The joint box according to claim 7, wherein a tip portion of said metal plate piece is folded back. 9. The wiring unit according to claim 1, wherein the wiring unit is formed of a bus bar substrate, and the connection terminal is a tab terminal formed by erecting a bus bar of the bus bar substrate. Joint box. 10. The electronic device according to claim 10, wherein the through holes are through holes formed in the circuit board for connecting wiring conductors formed on both sides of the circuit board constituting the electronic circuit unit. 10. The joint box according to any one of 1 to 9.