JP2000261135A - Electronic parts with self positioning function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic parts with self positioning function capable of installing the electronic parts on a printed circuit board with very accurate positioning. SOLUTION: A bottom face of an electronic parts body 10 has two bosses 14 and 16 for positioning. The boss 14 is integrally formed simultaneously with a plastic-made parts body 10 and the boss 16 formed by a shape memory alloy are integrally formed in line with a transformed stroke section 18. Boss hole of large diameter are formed on the printed circuit board correspondingly to each bosses 14 and 16. The electronic parts are mounted on the printed circuit board with each boss 14 and 16 inserted into each respective boss hole by an automatic mounter. The boss 16 and the transformed stroke section 18 are transformed by heat through a solder reflow process on the printed circuit board and each of bosses 14 and 16 is firmly inserted into each boss hole and positioned. After this, an electrode terminal 12 of the electronic parts is fixed by soldering.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component having a self-position control function which is automatically mounted on a printed circuit board.

[0002]

2. Description of the Related Art Conventionally, electronic components such as a volume, a headphone jack, and a switch, which are exposed on the surface of an electronic device product, must be arranged at an appropriate position in a process of assembling the product. Therefore, when mounting these components on a printed wiring board,
Strict positioning is required. As a structure for positioning and mounting these electronic components on the printed wiring board, a positioning projection (boss) is provided on the electronic component side, and a positioning hole is provided on the printed wiring board side, and the projection on the electronic component side is provided. Are aligned with the positioning holes on the printed wiring board and are mounted.

[0003]

However, when the projections on the electronic component side are aligned with the positioning holes on the printed wiring board side as described above, in order to obtain strict positioning accuracy, the electronic component needs to be positioned. The operation of aligning the projection on the side with the positioning hole on the side of the printed wiring board and fitting and inserting the same is a highly accurate operation. For example, it is difficult to perform the operation with an automatic mounting machine, and there is a problem that workability is poor. On the other hand, if the dimensional tolerance on the electronic component side, the dimensional tolerance on the printed wiring board side, and the mounting accuracy are given a margin to improve workability, the positional accuracy of the electronic components will deteriorate, and the product assembly process In such a case, there is a problem that a positional shift or the like occurs between the electronic component and another assembly component, so that effective assembly cannot be performed.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electronic component having a self-position regulating function which can easily mount an electronic component on a printed wiring board and can perform positioning with high accuracy. It is in.

[0005]

In order to achieve the above object, the present invention has a plurality of positioning projections inserted into positioning holes formed in a printed wiring board. In the electronic component with a self-position regulating function, which is disposed on the printed wiring board by the fitting of and is fixed to the printed wiring board by the solder reflow process, the plurality of protrusions are respectively fixed with respect to the positioning holes. At least one of the protrusions is formed of a shape memory element that is displaced in the direction of the surface of the printed wiring board in response to heat fluctuation, and at room temperature, The plurality of protrusions are inserted with a fixed gap into the positioning hole, and the protrusion formed by the shape memory element is Deformed by heating at the time of reflow,
Positioning the printed circuit board and the electronic component by displacing in a direction to eliminate the gap between each of the protrusions and the positioning hole,
Thereafter, the printed wiring board and the electronic component are fixed by solidification of the solder.

In the electronic component with a self-position regulating function of the present invention, when the electronic component is arranged on the printed wiring board, a plurality of positioning projections provided on the electronic component are provided with positioning holes formed on the printed wiring board. To perform the placement work. At this time, since each projection of the electronic component is formed to have a small diameter with respect to the positioning hole of the printed board and has a certain gap, the insertion operation can be easily performed. Next, the printed wiring board is fed to a reflow furnace, and the solder pattern arranged on the printed wiring board is heated by a solder reflow process. Due to this heating, the projections made of the shape memory element are displaced in a direction to eliminate the gap between each projection and the positioning hole, and each projection contacts the inner edge of the positioning hole. Thereby, the electronic component and the printed wiring board are accurately positioned. Thereafter, the solder solidifies, and the electronic component and the printed wiring board are fixed in a positioned state. As described above, it is possible to provide an electronic component that can satisfy both easy mounting work and accurate positioning accuracy.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of an electronic component with a self-position control function according to the present invention will be described. FIG.
1A and 1B are diagrams showing an electronic component with a self-position regulating function according to the present embodiment, wherein FIG. 1A is a side view and FIG. 1B is a bottom view. The electronic component includes a substantially rectangular parallelepiped component body 10, four electrode terminals 12 provided on both sides of the component body 10 so as to be exposed in pairs, and a component body 1.
And two bosses (protrusions) 14 and 16 for positioning protruding from the lower surface of the O.

The component body 10 is made of a synthetic resin molded article, and the boss 14 is formed integrally when the component body 10 is molded. The boss 14 is formed in a simple columnar shape. On the other hand, the boss 16 is formed of a shape memory alloy (shape memory element) and attached to the component body 10. On the base end side of the boss 16, a deformation stroke portion 18 formed with a constant stroke along the direction of the plate surface of the printed wiring board is integrally connected. That is, the boss 16 and the deformation stroke portion 18 form a substantially L-shaped alloy body.

The deformation stroke portion 18 is housed in a concave portion 10A provided on the lower surface of the component main body 10, and is disposed so as to be buried from the lower surface of the component main body 10. One end of the deformation stroke portion 18 is fixed to the component main body 10, and a boss 16 is provided at the other end of the deformation stroke portion 18. As a method of fixing the deformation stroke portion 18 and the component body 10, for example, bonding, riveting, or the like is used. With such a configuration, the boss 16
Is displaced in the direction of arrow A in FIG. And the sufficient deformation stroke at the time of thermal deformation can be obtained by the deformation stroke part 18 of a longitudinal shape,
The position of the boss 16 can be displaced with a sufficiently large stroke between the time of normal temperature and the time of heating.

FIG. 2 is a view showing a state in which the electronic component shown in FIG. 1 is mounted on a printed wiring board.
2A shows a state immediately before mounting, and FIG. 2B shows a state after mounting. As shown, boss holes (positioning holes) 32 and 34 are formed in the printed wiring board 30 corresponding to the bosses 14 and 16 of the electronic component. Each boss 14,
16 has a smaller diameter than each of the boss holes 32 and 34. The electronic component is sucked and held by the suction nozzle 40 of the automatic mounting machine, and is fed to a predetermined position on the upper surface of the printed wiring board 30 which is positioned and arranged in advance. Is each boss hole 3
The electronic components can be mounted on the printed wiring board 30 by being inserted into the printed wiring boards 2 and 34 and the lower surface of the component body 10 being placed on the printed wiring board 30. In this state, since each boss 14, 16 is formed to have a smaller diameter than each boss hole 32, 34, each boss 14, 16 and each boss hole 32, 34 have a sufficient gap G. And can be mounted with coarse positional accuracy.

FIG. 3 is an explanatory view showing a state in which the printed wiring board on which the electronic component shown in FIG. 2 is mounted is subjected to a solder reflow process. Printed wiring board 30 with electronic components mounted
Is supplied to the reflow furnace 50, and the solder pattern previously provided on the upper surface of the printed circuit board 30 is
After being heated, the electronic component is electrically connected to the wiring pattern on the printed wiring board 30 and solidified mechanically by solidification of the solder.

FIGS. 4A and 4B are views showing the positioning operation by the boss 16 made of a shape memory alloy during the solder reflow processing shown in FIG. 3, and FIGS. 4A and 4B are explanatory views showing a state before reflow. 4 (C) and 4 (D) are explanatory diagrams showing a state after reflow. 4A and 4B, the bosses 14, 16 and the boss holes 32, 3
4 has a sufficient gap G. However, FIG.
In the state at the time of reflow heating shown in (D), the boss 16 and the deformation stroke portion 18 are deformed by heat, and the boss 16 is displaced in the direction of arrow A, so that the two bosses 14, 1
6, the distance between each boss 14, 16 and each boss hole 3 is reduced.
The gap G between the bosses 2 and 34 is eliminated, and the bosses 14 and 16 come into close contact with the inner edges of the boss holes 32 and 34. Thereby, the electronic components are accurately positioned and arranged on the printed wiring board 30. At the same time as the displacement of the electronic component, the solder on the printed wiring board 30 is solidified by the heating, and the electrode terminals 12 of the electronic component are fixed by the solder in the heated state. Therefore, even when the temperature returns to normal temperature, the position of the boss 16 returns to the original position, but the electrode terminal 1 is soldered.
Since the electronic component 2 is fixed, the electronic component is held in the positioning state.

FIG. 5 is a view showing an electronic component with a self-position regulating function according to a second embodiment of the present invention.
1A is a side view, and FIG. 1B is a bottom view. In this example, two bosses 22 and 24 are each formed of a shape memory alloy. Each boss 22, 24 is shown in FIG.
Similarly to the boss 16 and the deformation stroke portion 18 shown in FIG. The bosses 22 and 24 are displaced in directions approaching each other (arrows B and C in the figure) due to the deformation of the deformation stroke portions 26 and 28 by heating. This allows
2, each boss 22, 24 can be inserted into the boss holes 32, 34 of the printed wiring board 30 with a sufficient gap G, and the electronic component can be mounted on the printed wiring board 30. Further, similarly to the example shown in FIG. 4, the bosses 22 and 24 are displaced by heating in the reflow process, the electronic component is positioned, and the solder can be fixed by solidification of the solder. The other configuration is the same as the example shown in FIG.
The same reference numerals are given to the same members, and the description is omitted.

FIGS. 6A and 6B are diagrams showing the operation of the boss 16A in the electronic component with a self-position regulating function according to the third embodiment of the present invention, and FIGS. 6A and 6B show the state before reflow. FIGS. 6C and 6D are explanatory diagrams showing a state after reflow. In the example shown in FIG. 4, the case where the boss 16 is displaced in the direction approaching the boss 14 has been described.
The boss 16A shown in FIG. 4 shows a case where it is displaced in a direction away from the boss 14A. Even in the case of such a direction of displacement, the electronic component can be positioned and fixed on the printed wiring board after reflow. The other configuration is shown in FIG.
Are the same as in the example shown in FIG. 1, and the same members are denoted by the same reference numerals and description thereof will be omitted.

FIG. 7 is a diagram showing an electronic component with a self-position regulating function according to a fourth embodiment of the present invention.
7A is a side view, and FIG. 7B is a bottom view. In the example shown in FIGS. 1 and 5, one boss 16 or two bosses 2
Although the electronic component is positioned in one direction by the linear displacement of 2, 24, in the example shown in FIG.
The displacement of the three bosses 62, 64, 66 enables two-dimensional positioning. That is, the first boss 62 is integrated with the deformation stroke portion 68, and is displaced in the direction of the arrow A in the figure by heating, like the boss 16 and the deformation stroke portion 18 shown in FIG.

Further, the second and third bosses 64 and 66 are integrated at both ends of a common deformation stroke portion 70.
The deformation stroke portion 70 is arranged in a direction orthogonal to the deformation stroke portion 68, and has a central portion fixed to the component body 10. Then, both ends of the deformation stroke portion 70 are displaced by the heating, and the bosses 64 and 66 are displaced in the approaching direction (directions of arrows D and E in the drawing). On the other hand, the bosses 62, 64, 66
Is provided with a large-diameter boss hole inserted with a gap G. After automatically mounting electronic components on the printed wiring board,
By the heating by the reflow process, the boss 62 is displaced in the direction of the arrow A, and the bosses 64 and 66 are displaced in the directions of the arrows D and E. It can be performed.

In each of the above examples, one boss hole is provided for each boss. However, one boss hole having a long shape is provided for two bosses and inserted into one boss hole. 2
The configuration may be such that the two bosses are separated from each other by heating and hit against the edge of the boss hole for positioning.

FIG. 8 is a diagram showing a specific example in which the above-described electronic component is applied to a volume. FIG. 8 (A) is a side view and FIG. 8 (B) is a bottom view. This volume is provided with bosses 84 and 86 and a deformation stroke portion 88 made of a shape memory alloy on the lower surface of a main body 82 provided with a circular knob 80. A plurality of electrode terminals 90 are provided on the side of the main body 82. Also in this example, each boss 8
The electrode terminals 90 are fixed by soldering in a state where the bosses 84 and 86 are displaced and the main body 82 is positioned by heating in the reflow process, by inserting the bosses 4 and 86 into boss holes of a printed wiring board (not shown).

FIG. 9 is a diagram showing a specific example in which the above electronic component is applied to a switch. FIG. 9 (A) is a side view and FIG. 9 (B) is a bottom view. This switch is provided with bosses 104 and 106 made of a shape memory alloy and a deformation stroke portion 10 on the lower surface of a main body 102 provided with a slide knob 100.
8 is provided. A plurality of electrode terminals 110 are provided on both sides of the main body 102. Also in this example, each of the bosses 104 and 106 is inserted into a boss hole of a printed wiring board (not shown), and the electrode terminals 110 are placed in a state where the bosses 104 and 106 are displaced and the main body 102 is positioned by heating in the reflow process. It is fixed by solder.

[0020]

As described above, the electronic component with a self-position regulating function of the present invention has a plurality of small-diameter projections each inserted with a fixed gap into the positioning hole of the printed wiring board. At least one projection is formed from a shape memory element that is displaced in the direction of the surface of the printed wiring board in response to thermal fluctuations. At room temperature, the plurality of projections are inserted into the positioning holes with a fixed gap. Then, the protrusion formed by the shape memory element is deformed by heating at the time of solder reflow, and is displaced in a direction to eliminate a gap between each protrusion and the positioning hole to position the printed wiring board and the electronic component. The printed circuit board and the electronic component are fixed by the solidification of the printed wiring board. Therefore, the mounting of the electronic component on the printed wiring board can be easily performed, and the positioning can be performed with high accuracy, so that both the easy mounting operation and the accurate positional accuracy can be satisfied. We can provide electronic components.

[Brief description of the drawings]

FIG. 1 is a diagram showing an electronic component with a self-position regulating function according to a first embodiment of the present invention, wherein FIG.
(B) is a bottom view.

FIGS. 2A and 2B are diagrams showing a state where the electronic component shown in FIG. 1 is mounted on a printed wiring board, wherein FIG. 2A shows a state immediately before mounting and FIG. 2B shows a state after mounting.

FIG. 3 is an explanatory view showing a state of performing a solder reflow process on a printed wiring board on which the electronic component shown in FIG. 2 is mounted.

4A is a view showing a positioning action by a boss made of a shape memory alloy at the time of a solder reflow process shown in FIG. 3, and FIG.
(B) is an explanatory view showing a state before reflow, (C) and (D).
FIG. 4 is an explanatory diagram showing a state after reflow.

5A and 5B are views showing an electronic component with a self-position regulating function according to a second embodiment of the present invention, wherein FIG.
(B) is a bottom view.

FIGS. 6A and 6B are diagrams showing an operation of a boss 16A in an electronic component with a self-position regulating function according to a third embodiment of the present invention, wherein FIGS.
(C) (D) is an explanatory view showing a state after reflow.

FIG. 7 is a diagram showing an electronic component with a self-position regulating function according to a fourth embodiment of the present invention, wherein (A) is a side view,
(B) is a bottom view.

8A and 8B are diagrams showing a specific example in which the electronic component of the present invention is applied to a volume, where FIG. 8A is a side view and FIG. 8B is a bottom view.

9A and 9B are diagrams showing a specific example in which the electronic component of the present invention is applied to a switch, wherein FIG. 9A is a side view and FIG. 9B is a bottom view.

[Explanation of symbols]

10: Component body, 12: Electrode terminal, 14, 16 ...
Boss, 18 Deformed stroke part, 30 Printed circuit board, 32, 34 Boss hole, 40 Suction nozzle,
50 Reflow furnace.

Claims (8)

[Claims] A plurality of positioning projections inserted into positioning holes formed in the printed wiring board, the positioning projections being fitted to the respective projections to be arranged on the printed wiring board, and In the electronic component with a self-position regulating function fixed to the printed wiring board by a solder reflow process, the plurality of protrusions are each formed into a small diameter that is inserted with a fixed gap with respect to the positioning hole. At least one of the protrusions is formed of a shape memory element that is displaced in the direction of the surface of the printed wiring board in response to heat fluctuations. At room temperature, the plurality of protrusions are fixed with respect to the positioning holes. While being inserted with a gap, the projections formed by the shape memory element are deformed by heating during the solder reflow, and each of the projections is deformed. And the printed wiring board and the electronic component are positioned by being displaced in a direction to eliminate the gap between the positioning hole and the positioning hole, and thereafter, the printed wiring board and the electronic component are fixed by solidification of the solder. Electronic components with self-position control function. 2. Some of the plurality of projections are projections formed from a shape memory element, and some of the remaining projections are projections formed of a synthetic resin. The electronic component with a self-position regulating function according to claim 1, wherein: 3. The electronic component with a self-position regulating function according to claim 1, wherein all of the plurality of projections are projections formed from a shape memory element. 4. A deformation stroke portion formed with a constant stroke along a plate surface direction of a printed wiring board is integrally and continuously provided at a base end portion of the projection formed by the shape memory element. The electronic component with a self-position regulating function according to claim 1, wherein one end of a deformation stroke portion is fixed to the electronic component, and the projection is provided at the other end of the deformation stroke portion. 5. The electronic component has a main body case made of a synthetic resin, and a plurality of electrode portions provided outside the main body case, wherein the protruding portion faces a printed wiring board of the main body case. The electronic component with a self-position regulating function according to claim 1, wherein the electronic component is provided on a lower side surface of the electronic component. 6. The positioning hole according to claim 1, wherein a plurality of positioning holes are provided corresponding to the plurality of projections.
Electronic component with self-position control function as described. 7. The electronic component with a self-position regulating function according to claim 1, wherein two or more of said projections are inserted into one said positioning hole. 8. A printed circuit board and an electronic component, wherein a plurality of projections formed by the shape memory element are provided, and the projections are displaced in directions different from each other to position the printed wiring board and the electronic component. Electronic component with self-position control function as described.