JP3349900B2 - How to assemble a printed circuit storage case - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed circuit board (hereinafter referred to as "PCB") or a flexible printed circuit (hereinafter referred to as "FPC") having a connector terminal fixed to an outer wall and connected to the connector terminal. The present invention relates to a method of assembling a printed circuit storage case to be stored.

[0002]

2. Description of the Related Art Conventionally, some cases for housing a printed circuit such as a PCB or an FPC have a connector integrally provided on an outer wall thereof. One example is shown in FIG.

[0003] In the illustrated storage case 80, the entire outer wall is integrally formed of synthetic resin or the like, and a top wall 82 and this top wall 8 are formed.
A plurality of (four in the case where the top wall 82 is rectangular) side walls 84 extending downward from the periphery of the second wall 82. A connector housing 86 that opens upward is formed integrally with the top wall 82, and a plurality of connector terminals 88 are fixed to the bottom wall of the connector housing 86 so as to penetrate vertically.

A PCB 90 and a sheet-shaped FPC 94 are stored in a storage case 80. Specifically, PC
The electronic circuit incorporated in the B90 and the FPC 94
2 are electrically connected by soldering, and the FPC 94 is substantially 180 ° inverted.
The lower end of the connector terminal 88 is passed through a through hole provided at the end of the FPC 94, and the FPC 94 and the connector terminal 88 are electrically connected by soldering the through portion 96.

According to this case, the housing of the connector connected to the circuit outside the case is fitted into the connector housing 86 of the storage case 80 and the two connectors are connected, so that the circuit outside the case and the FPC 84 are connected. Can be easily connected.

[0006]

In the storage case 80, the soldering operation for connecting the connector terminal 88 and the FPC 94 must be performed in an extremely narrow space surrounded by the side wall 84. Therefore, in order to perform the soldering, a method of contacting each connection point with the circulating molten solder at a time (ie, flow soldering)
Cannot be used, and one 1
It is necessary to perform soldering manually for each book. Manual soldering in such a narrow space requires a great deal of labor and time, and greatly hinders cost reduction.

SUMMARY OF THE INVENTION In view of such circumstances, an object of the present invention is to provide a method of simplifying the work of soldering a connector terminal and a printed circuit in a printed circuit storage case integrally provided with a connector. I do.

[0008]

As a means for solving the above problems, the present invention has an outer wall surrounding a printed circuit, and a connector terminal is fixed to the outer wall so as to penetrate the outer wall. A method of assembling a printed circuit storage case in which the printed circuit is connected to a terminal,
In a state in which the entire outer wall is developed in a substantially planar shape, the connector terminal fixed to the outer wall and a printed circuit are soldered by flow soldering, and then the entire outer wall is assembled.

According to this method, the connector terminal fixed to the outer wall and the printed circuit can be easily connected by soldering in a state where the entire outer wall of the storage case is developed in a substantially planar shape. In particular, by soldering each connection point at a time by flow soldering, the labor and time required for the soldering operation can be significantly reduced.

Here, if the holding portion for holding the printed circuit in the assembled state is formed on the inner surface of the outer wall, the printed circuit can be easily fixed to the case at the same time as the case is assembled.

If an engaging portion is provided at each end of each side wall which is adjacent to the other side wall and is engaged with each other in the above-mentioned assembled state to join the side walls together, the side walls can be easily stored without using an adhesive or the like. Cases can be assembled.

The storage case assembled by the method of the present invention may be used alone or may constitute a part of the case of the electric junction box. In the latter case, when the printed circuit is stored in the storage case and the storage case is assembled to the electric connection box, the printed circuit can be easily set in the electric connection box.

[0013]

FIG. 1 shows a first embodiment of the present invention.
This will be described with reference to FIG.

FIG. 1 shows an electric junction box provided in an automobile or the like. This electric connection box has a lower case 10 and an upper case 12, and a bus bar substrate 14 is housed in both cases 10, 12. The upper wall of the upper case 12 is provided with a through hole for exposing a part of the bus bar substrate 14 upward, and a frame 13 is formed around the through hole.

Inside the frame 13, a PCB 16 and F
The PC 18 is to be stored. Various electronic circuit elements and a board connector 15 are mounted on the front surface (the lower surface in the figure) of the PCB 16.
5 is fitted to an appropriate tab of the bus bar board 14 so that the bus bar of the bus bar board 14 and the electronic circuit on the PCB 16 are connected. FPC18
Is a circuit in which a circuit is printed on a sheet that can be flexibly deformed. One terminal of the circuit is connected to the terminal of the PCB 16, and a through hole 18a for soldering described later is formed in a portion corresponding to the other terminal. Has been established.

A lid-shaped storage case 20 is fitted to the outside of the frame 13 so as to cover the frame 13. That is, the storage case 20 is
In addition to serving as a storage case surrounding the FPC 18, it also serves as a cover forming a part of the case of the electric connection box. A connector 22 is provided integrally with the outer wall of the storage case 20 so that the FPC 18 and a circuit outside the case can be electrically connected via the connector 22.

The details of the structure of the storage case 20 are shown in FIG.
(A) and (b). The storage case 20 has a top wall 24 as a main body wall and four side walls, that is, a front side wall 25, a rear side wall 26, and left and right side walls 28 integrally as the outer wall. Is provided with the connector 22. The top wall 24 and each of the side walls 25, 26, 28 are connected via a thin hinge portion 30 and can be bent by the hinge portion 30. By this bending, the entire outer wall is unfolded in a substantially planar shape as shown in FIGS. 2 (a) and 2 (b), and each side wall 25, 26, 28 can be switched to an assembled state in which the lower side stands upright.

As shown in FIG. 3A, each connector 22
Is composed of a connector housing 32 and a plurality of connector terminals 34. The connector housing 32
Has a shape that opens upward, and is formed integrally with the top wall 24. Each connector terminal 34 is a pin-shaped male terminal in this embodiment, and
2 is fixed to the bottom wall while penetrating vertically through the bottom wall.

In the present invention, regardless of the means for fixing the connector terminal 34 to the case body wall (the top wall 24 in FIG. 3), both may be molded integrally, or as shown in FIG.
It may be fixed by press fitting as shown in FIG. In the example of FIG. 3B, a through hole 32a for fixing the terminal is formed in the bottom wall of the connector housing 32, while the maximum width of the distal end of the connector terminal 34 is larger than the diameter of the through hole 32a. An arrow-shaped locked portion 34a is formed, and a flange portion 34b is formed from the locked portion 34a with a dimension substantially equal to the thickness of the bottom wall of the connector housing 32. According to this structure, the locked portion 34a is inserted through the through hole 3 until the flange 34b comes into contact with the upper surface of the housing bottom wall.
By strongly pushing the connector terminal 34 into the connector terminal 2a, the connector terminal 34 can be fixed.

The inner surfaces of both ends of the rear side wall 26 and the sides of the left and right side walls 28 adjacent to the front side wall 25 (FIG. 2A)
(The left side in (b)) has these side walls 26,
A male engagement portion 36 is provided integrally with the projection 28. An arrow-shaped head is formed at the tip of the male engagement portion 36, and a slit 36a is cut into the head, and the maximum width of the head can be reduced by the width of the slit 36a. It has become.

On the other hand, the inner surfaces of both ends of the front side wall 25,
The side of the left and right side walls 28 adjacent to the rear side wall 26 (FIG. 2)
A female (portal) engaging portion 38 into which the head of the male engaging portion 36 can be press-fitted integrally with the inner surfaces of the ends (right side in FIGS. Is protruding. When the storage case 20 is bent at the hinge portion 30 from the unfolded state and shifts to the upright state, the male engagement portion 36 is pressed into the female engagement portion 38 as shown in FIG. Thereby, the connected state between the front and rear side walls 25 and 26 and the left and right side walls 28 is maintained.

A pair of upper and lower substrate holding projections 40 extending in the horizontal direction in the assembled state are provided on the inner surfaces of the central portions of the front side wall 25 and the left and right side walls 28. The positions of the board holding projections 40 are determined so that the periphery of the PCB 16 housed in the storage case 20 in the above assembled state is fitted into the groove 42 between the board holding projections 40 (that is, both board holding projections). The ridge 40 is set at a position where the periphery of the PCB 16 is clamped from above and below.

Next, a method of assembling the storage case 20 will be described.

As shown in FIGS. 5 and 6, the PCB 1
The pins 44 are soldered to the terminals 6 through the PCB 16, and the pins 44 are inserted into the through holes provided at positions corresponding to the one terminals of the FPC 18 from above.
The storage case 20 is kept in the unfolded state, and the lower end of each connector terminal 34 projecting to the back side is connected to each through-hole 18 a provided at a position corresponding to the other terminal of the FPC 18.
Plug in.

The storage case 20 while maintaining the state of
And the like are set in a flow soldering apparatus, and a portion of the FPC 18 through which the pins 44 and the connector terminals 34 pass is soldered at a time. In the present invention, the specific configuration of the flow soldering apparatus is not limited, but a preferred example is shown in FIG. In the figure, a pair of left and right rails 50 (a pair of the front side and the back side in FIG. 7) are arranged in the case conveyance direction.
A flux coating device 52, a preheater 54, a solder bath 56, and a cooling fan 58 are arranged below the rail 50 in this order from the upstream side (the left side in the drawing) in the transport direction. Is provided with a transfer device (not shown) for transferring a work along the work. When the storage case 20 and the like in this state are set in this apparatus, first, the FPC 18 is
Is applied to the lower surface of the FPC 1, the lower surface is heated by a preheater 54, and the lower surface contacts the molten solder circulating in the solder bath 56, so that the FPC 1
8 and the pins 44 and the respective connector terminals 34 are soldered at one time. Thereafter, the FPC 18 and the like are cooled by the cooling fan 58 and discharged from the device.

When the storage case 20 is set in the flow soldering apparatus, for example, a spacer 46 having a shape surrounding the periphery of the FPC 16 as shown by a two-dot chain line in FIGS. If the molten solder is interposed between the lower surface of the case 20 and the case 20, it is possible to prevent the molten solder from directly contacting the case 20, and the case 20 can be more reliably protected from the high heat of the molten solder.

As shown in FIG. 8, the FPC 18 is located rearward of the portion connected to the connector terminal 34 (rightward in FIG. 8).
And the PCB 16 connected to the FPC 18 is kept horizontal at a position below the connector terminal 34. In this state, the side walls 25, 26, 28 are bent downward by approximately 90 ° with respect to the top wall 24 by the hinge portion 30, and the respective side walls 26, 28 are fitted into the respective grooves 42 while fitting the peripheral edge of the PCB 16. Is engaged with the female engaging portion 36 of each side wall 25, 28. As a result, the front and rear side walls 25 and 26 and the left and right side walls 28 can be connected to maintain the assembled state as shown in FIG. 8, and at the same time, the PCB 16 can be fixed to the storage case 20 side. When the storage case 20 is fitted and fixed to the outside of the frame 13 of the upper case 12 shown in FIG.
C18 can be incorporated into the electrical junction box at the same time.

As described above, since the outer wall of the storage case 20 is configured to be expandable, soldering by flow soldering can be performed without any trouble in the expanded state. Therefore, as compared with a case where the soldering is performed manually for each connector terminal 34, the labor and time required for the soldering operation can be greatly reduced, and further, automation can be achieved. Further, even when soldering is performed manually instead of the flow soldering, the work can be greatly facilitated as compared with the conventional soldering in a narrow space surrounded by side walls.

Furthermore, since the side walls 25, 26, 28 are provided with engaging portions 36, 38 which engage with each other,
At the time of assembling the case, the side walls can be connected by a simple operation of merely engaging the engaging portions 36 and 38, and the assembling operation can be performed more easily than when this connection is performed with, for example, an adhesive.

The substrate holding projections 40 are previously formed on the inner surface of the side wall.
The printed circuit board 16 can be fixed to the storage case 20 at the same time as the case is assembled, so that the operation can be further simplified.

The embodiment of the present invention is not limited to this, but can take the following forms as examples.

(1) In the first embodiment, the case where both the FPC 18 and the PCB 16 are stored in the storage case 20 has been described, but the storage case according to the present invention is the FPC 1
8, only one of the FPCs 16 may be stored. In the case where only the PCB 16 is stored, the lower end of the connector terminal 34 may be directly soldered and connected to the PCB 16 as shown in FIG. 9 as a second embodiment.
In this case, it is more preferable that a holding portion for holding the PCB 16 on the storage case 20 side in the expanded state shown in FIG.

(2) In the first embodiment, the case where the storage case 20 forms a part of the case of the electric connection box has been described. However, the storage case according to the present invention can be used alone as the FPC 18. Or a printed circuit such as a PCB 16 or the like. For example, it may be used alone in the assembled state shown in FIG. 8, or in the assembled state, a bottom wall may be attached to the lower end of the side walls 25, 26, 28, or any of the side walls 25, The bottom wall may be integrally connected to 26 and 28 via a hinge portion 30.

(3) In the present invention, the development pattern of the outer wall of the case is not limited to that shown in FIG. 2A, and various patterns generally known as development patterns of various polyhedrons such as a rectangular parallelepiped and a cube may be used. It can be applied as it is.

[0035]

As described above, the present invention has an outer wall surrounding a printed circuit, a connector terminal is fixed to the outer wall in a state penetrating the outer wall, and the printed circuit is connected to the connector terminal. A method of assembling a circuit storage case, in which a connector terminal fixed to an outer wall and a printed circuit are soldered by flow soldering in a state where the entire outer wall is expanded in a substantially planar shape, and then the entire outer wall is assembled. Therefore, there is an effect that the connector terminal fixed to the outer wall and the printed circuit can be easily connected by soldering in the expanded state. In particular, by soldering each connection point at a time by flow soldering, the labor and time required for the soldering operation can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an electric connection box according to a first embodiment of the present invention.

FIG. 2A is a bottom view showing a state in which a printed circuit storage case constituting a part of the electric connection box is expanded.
(B) is a sectional view taken along line AA of (a).

FIG. 3A is a cross-sectional view of a connector provided in the printed circuit storage case, and FIG. 3B is a cross-sectional view showing a modified example of the connector.

FIG. 4 is a cross-sectional front view showing a manner in which a male-type engaging portion and a female-type engaging portion provided on the printed circuit storage case are engaged.

FIG. 5 is a cross-sectional front view showing a state in which the printed circuit storage case is developed and flow soldering is performed.

FIG. 6 is a bottom view showing the state of FIG. 5;

FIG. 7 is a diagram illustrating an example of an apparatus for performing the flow soldering.

FIG. 8 is a sectional front view showing an assembled state of the printed circuit storage case.

FIG. 9 is a cross-sectional front view showing an expanded state of a printed circuit storage case according to a second embodiment of the present invention.

FIG. 10 is a cross-sectional front view showing an example of a conventional printed circuit storage case.

[Explanation of symbols]

 16 PCB (Printed Circuit Board) 18 FPC (Flexible Printed Circuit) 20 Storage Case 22 Connector 24 Top Wall (Main Body Wall) 25 Front Side Wall 26 Rear Side Wall 28 Left and Right Side Wall 30 Hinge 32 Connector Housing 34 Connector Terminal 36 Male Engagement 38 Female type engaging part 40 Substrate holding ridge (holding part)

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Takahiro Onizuka 1-7-10 Kikuzumi, Minami-ku, Nagoya-shi, Aichi Harness Research Institute, Inc. (58) Field surveyed (Int. Cl. ⁷ , DB name) H05K 5/00

Claims (1)

(57) [Claims] 1. A method of assembling a printed circuit storage case, comprising: an outer wall surrounding a printed circuit; a connector terminal fixed to the outer wall so as to penetrate the outer wall; and the printed circuit connected to the connector terminal. A printed circuit storage case, wherein the connector terminal fixed to the outer wall and the printed circuit are soldered by flow soldering in a state where the entire outer wall is substantially flattened, and the entire outer wall is assembled. Assembly method.