JP2001024360A - Board-fixing mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To fix a wiring board rigidly to a case with a simple operation. SOLUTION: A wiring board 1 inserted in a case 11 is held with a holding segment 16 formed on a case side plate 12 facing the end portion of the board and fixed to the holding segment 16 through soldering. The holding segment 16 consists of a tongue body formed by cutting and lefting the insertion side of the board as a base end portion 17, with an substantially recess clipped trench 15 which is formed on a case side plate 12. The base end portion 17 of the holding segment 16 is bent in such a manner that a tip part 18 is made to gradually protrude toward the inside of the case 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit board mounting mechanism capable of securely mounting a wiring board or the like in a case of an electronic device or the like by a simple operation.

[0002]

2. Description of the Related Art In an electronic device or the like, a mounting portion is integrally formed on a metal case, and a wiring substrate is mounted on the mounting portion and soldered to the mounting portion to perform mounting of the wiring substrate and ground connection. Is provided. The conventional board mounting mechanism 100 has a tongue-like shape formed by cutting out a notch groove 102 having a downward U-shape formed at a plurality of appropriate positions on a case side plate 101 as shown in FIG. It is constituted by a plurality of holding pieces 103. In the state where the wiring board 104 is inserted into the case and positioned and mounted on the support portion 105, the board mounting mechanism 100 moves the holding pieces 103 inward as shown by the chain line in FIG. Bend to

[0003] The board mounting mechanism 100 urges the wiring board 104 to be supported by the supporting section 10 by the base end of each bent holding piece 103.
In a state where the wiring board 104 is pressed and held, the wiring board 104 is fixed by soldering 106 to each holding piece 103 and a ground pattern (not shown) formed on the wiring board 104 as shown in FIG. Board mounting mechanism 100
In this configuration, the wiring board 104 is
01 and the case side plate 101
The ground of the wiring board 104 is taken through the.

A conventional board mounting mechanism 1 shown in FIG.
Reference numeral 10 denotes a plurality of tongue-shaped holding pieces 113 that are left uncut by notched grooves 112 having an upward U-shape formed at appropriate locations on the case side plate 111. When the wiring board 114 is inserted into the case and positioned and mounted on the support portion 115, the board mounting mechanism 110 moves the holding pieces 113 inward as shown in FIG. Is folded.

[0005] In the board mounting mechanism 110, the tip of each bent holding piece 113 is brought into contact with the main surface of the wiring board 114. The board mounting mechanism 110 holds the wiring board 114 by pressing the wiring board 114 against the supporting portion 115 by the holding pieces 113. In this state, the board mounting mechanism 110 fixes the wiring board 114 by performing soldering 116 to each holding piece 113 and a ground pattern (not shown) formed on the wiring board 114. With this configuration, the board mounting mechanism 110 securely fixes the wiring board 114 to the case side plate 111, and the wiring board 114 through the case side plate 111.
Be sure to ground yourself.

[0006]

In the above-described conventional board mounting mechanism 100 and board mounting mechanism 110, after mounting the wiring boards 104 and 114 in the cases, a plurality of holding pieces 103 and 113 are formed. A crimping process for bending inward was necessary. The conventional substrate mounting mechanism 100 and the conventional substrate mounting mechanism 110 have a problem that the number of assembling steps is increased by performing the caulking process at a large number of locations.

Further, in the board mounting mechanism 100, since the soldering 106 is applied to the base end of each holding piece 103, there is a problem that the heat of the solder increases and the thermal influence on each component is large. Also, the board mounting mechanism 100
However, since each holding piece 103 has a large mechanical rigidity at the base end thereof, there is a problem that cracks easily occur due to the effect of heat shrinkage distortion directly on the solder 106.

On the other hand, in the board mounting mechanism 110, soldering 116 is performed at the tip of each holding piece 113 as described above. Therefore, in the board mounting mechanism 110, the influence of the solder heat on the components is suppressed, and the elastic shrinkage generated in each of the holding pieces 113 absorbs the heat shrinkage distortion, which may cause the solder 116 to crack. It will be suppressed.

However, such a substrate mounting mechanism 110
In the case where the holding pieces 113 are caulked in a state where the wiring board 114 is not assembled to a predetermined position in the case,
This causes a problem that the device is damaged. Therefore, the board mounting mechanism 110 needs a step of checking whether or not the wiring board 114 has been inserted to a predetermined position in the case. Since the caulking process must be performed in the checked state, the overall There is a problem that the number of assembling steps increases.

Accordingly, the present invention has been made to solve the above-mentioned problems of the conventional board mounting mechanism and to provide a board mounting mechanism capable of firmly fixing a board to a case by a simple operation. It is intended.

[0011]

A board mounting mechanism according to the present invention for achieving the above object holds a board inserted in a case by a holding piece formed on a side plate opposed to an end of the board. Then, the holding piece is fixed by soldering. The board mounting mechanism has a tongue piece in which the holding piece is formed by cutting off the board insertion side as a base end by a substantially concave cutout groove formed in the side plate, and bending the base end to form a tip end. The side is configured to gradually project inward. In addition, the tip end of the holding piece is formed wider than the base end. According to the board mounting mechanism according to the present invention configured as described above, the board inserted into the case has its end abutting against the tip of the holding piece,
It is incorporated inside by spreading it out. The board mounting mechanism prevents the holding piece returned to the initial position from lifting the board by its free end. The board mounting mechanism solders the board and the holding piece in this state,
The board is firmly fixed in the case.

Further, in the board mounting mechanism, the front end of the holding piece is made wider with respect to the base end, so that the base end can be easily bent and solderability is improved. Is fixed more firmly in the case.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of a board mounting mechanism according to the present invention. The board mounting mechanism 10 is formed integrally with a case side plate 12 of a case 11 formed, for example, in a box shape by pressing a metal plate as shown in FIG. The board mounting mechanism 10 includes a plurality of holding units 1 inserted into the case 11 and provided on the case bottom plate 13 as described later.
The wiring board 1 placed in a state of being positioned on the wiring board 4 is mounted and fixed.

As shown in FIG. 1, the wiring board 1 has an appropriate circuit burn 2 formed on an insulating substrate, for example.
A plurality of ground patterns 3 are appropriately formed near a side end portion facing the case side plate 12 in a state where the ground pattern 3 is mounted in the case 11. A positioning hole 4 is formed in the wiring board 1 corresponding to the holding portion 14 of the case 11 so that a positioning protrusion 14 a protruding from an upper end thereof is relatively engaged. The wiring pattern 1 is formed by soldering the ground pattern 3 to the case 11 as described later in detail.
In this case, it is fixed mechanically and grounded by being electrically connected.

The board mounting mechanism 10 has a tongue-like holding piece 16 which is left uncut by a plurality of notch grooves 15 having an upward U-shape formed in the case side plate 12.
Composed of That is, each holding piece 16 is formed of a strip having the base end 17 on the upper end side integrated with the case side plate 12 and the free end end 18 on the lower end side. Each holding piece 16 is formed on the case side plate 12 at a position corresponding to each ground pattern 3 of the wiring board 1 inserted into the case 11 and positioned and mounted on the holding portion 14.

Each of the holding pieces 16 is formed by bending the base end portion 17 inward when the case body 11 is manufactured by press working, so that the front end portion 18 is made to have the case body 1 in advance.
It is configured to be gradually protruded into one. Each holding piece 1
6 is a clearance c between the side end of the wiring board 1 inserted into the case 11 and the case side plate 12 so that the base end 17 adjusts the protrusion amount x of the front end 18 as shown in FIG. It is bent so that it is slightly larger than it is. Each holding piece 16 has a tip portion 18 at a height position substantially equal to the thickness of the wiring board 1 with respect to the holding portion 14.

The wiring board 1 is inserted into the case 11 from above, as shown in FIG. Wiring board 1
When it is inserted to a predetermined position, its side end
Of the holding pieces 16 projecting inward, but are further inserted while pushing the holding pieces 16 outward as shown by the chain line in FIG. The wiring substrate 1 is placed on the holding portion 14 by positioning the positioning protrusions 14 a relative to the positioning holes 4.

In the board mounting mechanism 10, each holding piece 16 that has been pushed outward while the wiring board 1 is positioned and mounted on the holding portion 14 elastically returns to the initial state, and FIG. As shown in FIG.
Abut on the main surface. The board mounting mechanism 10 includes the holding pieces 16
By pressing the wiring board 1 onto the holding portion 14 by this, the floating of the wiring board 1 is prevented. In this state, the distal end portion 18 of each holding piece 16 of the board mounting mechanism 10 is positioned corresponding to the ground pattern 3 of the wiring board 1.

The board mounting mechanism 10 is configured such that each holding piece 16 is soldered to the ground pattern 3 of the wiring board 1 so that a solder solder 19 is provided as shown in FIG.
To fix the wiring board 1 to the case 11. The board mounting mechanism 10 connects the ground of the wiring board 1 to the case 11 via each holding piece 16 and the solder brazing 19. The soldering is performed by an appropriate soldering method such as reflow soldering, hand soldering or dip soldering.

As described above, the board mounting mechanism 10 does not require a caulking process after assembling the wiring board 1 because each holding piece 16 has its tip 18 projecting into the case 11 in advance. . Therefore, the board mounting mechanism 10 reduces the number of assembling steps as compared with the conventional board mounting mechanism, and does not cause the problem of damaging the wiring board 1 during the caulking process.

The board mounting mechanism 10 causes a so-called click feeling because the insertion force suddenly decreases when the wiring board 1 has passed through the distal end portion 18 of each holding piece 16. Therefore, the board mounting mechanism 10 is configured such that the wiring board 1
By confirming the state of being positioned and mounted on the mounting portion 14, the insertion operation is surely performed.

The board mounting mechanism 10 suppresses the influence of the heat of the solder on each component by performing soldering at the tip 18 of each holding piece 16. The board mounting mechanism 10 includes:
The occurrence of cracks in the solder 19 is suppressed because the heat shrinkage distortion is absorbed by a certain amount of elastic displacement generated in each holding piece 16. The board mounting mechanism 10 includes a case 11
When a shock or the like is applied from the outside, the elastic displacement of each holding piece 16 absorbs the shock, thereby suppressing the occurrence of cracks and peeling in the solder brazing 19. Therefore, the board mounting mechanism 10 securely mounts and fixes the wiring board 1 to the case 11.

In the above-described substrate mounting mechanism 10, each holding piece 16 is formed in a strip shape having the same width dimension, but the present invention is not limited to this configuration. The holding piece 20 shown in FIG. 3 is configured such that the side edge is formed in a concave shape and the tip end portion 22 is wide due to the shape of the cutout groove 21. The other configuration is the same as the above-described configuration, and thus the description thereof is omitted.

The holding piece 20 has a wider tip end 22 to increase the solder solder attachment area, thereby improving the solderability and improving the bonding strength of the wiring board 1. Further, the holding piece 20 has a high elasticity due to the formation of the narrow portion 23 in the middle thereof, so that the reliability against the thermal shrinkage of the solder solder and the impact from the outside can be improved. .

In the above-described embodiment, the board mounting mechanism 10 of the wiring board 1 which is mounted on the case 11 and is grounded has been described. However, it is needless to say that the present invention is not limited to such a wiring board 1. is there.
If the wiring board does not particularly need to be grounded, a pattern for a soldered portion may be formed instead of the ground pattern.

[0026]

As described above in detail, according to the board mounting mechanism of the present invention, the free end side of the case side plate gradually projects inward from the insertion side of the board as the base end. By forming the bent tongue-shaped holding piece integrally, this holding piece is pushed out to prevent floating of the board incorporated inside and firmly fixed by soldering in this state Is done. The board mounting mechanism eliminates the need for a caulking step for holding the board, and also suppresses the influence of solder heat on each part by performing soldering at the tip of the holding piece, and prevents cracks caused by heat shrinkage of the solder part. Occurrence is also suppressed, and firm mounting of the substrate is enabled.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a main part for explaining a configuration of a substrate mounting mechanism shown as an embodiment of the present invention.

FIG. 2 is an essential part longitudinal cross sectional view for explaining an operation of attaching and fixing a wiring board to a case.

FIG. 3 is a main part side view for explaining another substrate mounting mechanism.

4A and 4B are diagrams illustrating a configuration of a conventional board mounting mechanism, wherein FIG. 4A is a side view of a main part, and FIG. 4B is a longitudinal sectional view of a main part.

5A and 5B are diagrams for explaining the configuration of another conventional substrate mounting mechanism, wherein FIG. 5A is a side view of a main part, and FIG. 5B is a longitudinal sectional view of the main part.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wiring board 2 Circuit pattern 3 Ground pattern 4 Positioning hole 10 Board mounting mechanism 11 Case 12 Case side plate 13 Case bottom plate 14 Mounting part 15 Cutout groove 16 Holding piece 17 Base end part 18 Top end part 19 Solder wax 20 Holding piece 21 Cutout groove 22 Tip

Claims (2)

[Claims] 1. A board mounting mechanism for holding a board inserted into a case by a holding piece formed on a case side plate opposed to an end thereof, and fixing the board to the holding piece by soldering. In the above, the holding piece is formed of a tongue piece formed by leaving the insertion side of the substrate as a base end by a substantially concave cutout groove formed in the case side plate, and the tip part gradually becomes toward the inside of the case. A substrate mounting mechanism, wherein a base end portion is bent so as to protrude. 2. The board mounting mechanism according to claim 1, wherein the holding piece has a free end formed wider than a base end.