JPH06217392A - Terminal structure for surface mount type electronic component - Google Patents

Abstract

PURPOSE:To secure soldering of terminals. CONSTITUTION:A soldering surface 14 of a terminal 3 is provided to a bottom surface of a package 1. A piezoelectric vibrator 2 is accommodated in the package 1 and the terminal 3 is connected electrically to the piezoelectric vibrator 2. A groove 11 is added to a bottom surface of the package 1 and a projecting part 15 is formed on one of surface and a recessed part 16 is formed on the other surface of the soldering surface 14 by cutting and raising part of the plate surface or deforming it. The soldering surface 14 is overlapped on the bottom surface of the package 1 while covering the groove 11 and the projecting part 15 is hooked in the groove 11 to act like a stopper for the terminal 3 and the recessed part 16 is a ditch receiving cream solder at the time of mounting.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal structure for a surface mount type electronic component which is surface mounted on a wiring board.

[0002]

2. Description of the Related Art In the surface mounting method, an electronic component is mounted on a cream solder placed on a wiring board, the cream solder is melted, and the terminals of the electronic component are dipped in the molten solder on the board and solidified as it is. This is the method to complete the implementation.
The electronic components used in this method usually have terminals provided on the bottom surface of the package, but there are also cases where terminals are provided so as to project laterally from the bottom surface.

[0003]

By the way, in the surface mount type electronic component, the area of the soldering surface of the terminal is generally small, and reliability of soldering on the wiring board is often a problem.

An object of the present invention is to provide a terminal structure for a surface mount type electronic component in which reliability of soldering to the terminal is increased.

[0005]

In order to achieve the above object, the terminal structure of a surface mount type electronic component according to the present invention is a terminal structure of a surface mount type electronic component having a terminal in a package of the electronic component. The package has a groove in a part of the bottom surface, the terminals are electrically connected to the elements in the package, and have a soldering surface, and the soldering surface has a plate shape and is overlapped by covering the groove of the package. The protrusion has a protrusion and a recess, and the protrusion is a retaining member that engages in the groove to prevent the protrusion from the package, and the recess cuts and raises the protrusion, or It is a recess that is formed on the other surface of the soldering surface by deformation and receives the cream solder during mounting.

[0006]

The concave portion provided on the soldering surface of the terminal receives the melted cream solder when the electronic component is mounted, and the solder is solidified as it is, so that the soldering becomes firm and the concave portion on the opposite side of the concave portion is provided. The protrusion formed on the surface engages with the groove of the package and functions as a stopper for preventing the terminal from falling off.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. The embodiment shows an example applied to a piezoelectric speaker. The sounding body M is an electronic component that inputs an electric signal to a vibrator to generate sound. In FIG. 1, a piezoelectric vibrator 2 is built in a package 1, and a terminal 3 is connected to the piezoelectric vibrator 2.

The package 1 is an assembly of a case 4 and a bottom plate 5. The case 4 has a bottomless cylindrical shape, a sound output hole 6 is opened on the upper surface, and a pair of cutouts 7 are faced to each other on the opening edge of the bottom. As shown in FIG. 8 is formed.

The bottom plate 5 has a disk shape to be fitted in the opening of the case 4, and has a rectangular projecting edge 9 to be engaged with the notch 7 of the case on a part of the peripheral edge so as to face each other. A rising portion 10 to be locked in the case 4 is integrally formed on the peripheral edge portion except the protruding edge 9.

The projecting edge 9 is a portion for locking the terminal 3, and the groove 1 is formed on the bottom surface of the bottom plate 5 corresponding to the projecting edge as shown in FIG.
1 is opened.

The terminal 3 integrally has a mounting portion 12 and an elastic contact piece 13 for contacting the electrode of the piezoelectric vibrator 2, and the mounting portion 1
Reference numeral 2 denotes a portion to be locked to the projecting edge 9 of the bottom plate 5, which is bent in a U shape, and the lower edge thereof is the soldering surface 14. As shown in FIGS. 2 and 3, part of the plate surface of the soldering surface 14 is cut and raised or deformed to project the protrusion 15 on the upper surface and form the recess 16 on the lower surface. The concave portion 16 is a dent formed on the plate surface by cutting and raising the protrusion.

In FIG. 2, the piezoelectric vibrator 2 is housed in a case 4, and the projecting edges 9 of the bottom plate 5 are engaged with the mounting portions 12 of the terminals 3 to hold the elastic contact pieces 13 on the bottom plate 5 in an inclined posture. Then, when the projecting edge 9 is fitted in the notch 7 of the case and the rising portion 10 is fitted in the case 4, the piezoelectric vibrator 2 becomes the step portion 8 of the case 4 and the rising portion of the bottom plate 5. 10
And the elastic contact piece 13 is attached to each electrode of the piezoelectric vibrator 2.
Come into contact with.

On the other hand, the upper surface side of the mounting portion 12 of the terminal 3 is supported by the projecting edge 9 and pressed against the inner edge of the notch 7 of the case 4, and the soldering surface 14 on the lower surface side is superposed on the lower surface of the bottom plate 5. As a result, the protrusion 15 is fitted into the groove 11 to prevent the terminal 3 from coming off.

In mounting, when the sounding body M is mounted on the wiring board P at a predetermined position with a predetermined pressure, the cream solder printed on the wiring board is recessed in the soldering surface 14 of the terminal 3.
After penetrating into 6 and passing through the soldering furnace, the solder is solidified as it is, and the terminal 3 is firmly bonded onto the wiring.

In the above embodiments, the example applied to the package of the piezoelectric type sounding body has been described.
In addition to general semiconductor devices, thermistors, and varistors,
The same applies to packages of resistors and other devices.

[0016]

As described above, according to the present invention, the terminal is mounted by covering the groove provided on the bottom of the package, and a part of the soldering surface of the terminal is cut and raised or deformed to form a protrusion on one surface. Since the recess is formed on the other surface, a recess can be formed on the soldering surface of the terminal that engages the protrusion in the groove and receives the cream solder during mounting, and the solder is inserted into the recess and solidified to ensure the wiring of the terminal. Can be fixed on the substrate. Further, it is possible to obtain the effect of preventing the terminal from coming off from the package in which the protrusion is engaged in the groove.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a main part.

FIG. 3 is a bottom view of essential parts showing a soldering surface.

[Explanation of symbols]

 1 Package 2 Piezoelectric vibrator 3 Terminal 4 Case 5 Bottom plate 6 Sound emission hole 7 Notch 8 Step part 9 Projection edge 10 Rise part 11 Groove 12 Mounting part 13 Elastic contact piece 14 Soldering surface 15 Protrusion 16 Recess

Claims (1)

[Claims] 1. A terminal structure of a surface mount type electronic component having a terminal in a package of electronic component, wherein the package has a groove in a part of a bottom surface, and the terminal is electrically connected to an element in the package. , Having a soldering surface, the soldering surface having a plate-like shape and being stacked so as to cover the groove of the package, and having a protrusion and a recess, the protrusion engaging in the groove The recess is a recess that is formed on the other surface of the soldering surface by cutting and raising or deforming the protrusion and that receives the cream solder during mounting. The terminal structure for surface mount electronic components.