JP2872023B2 - Surface mount connector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mount connector to be mounted on a circuit board, and more particularly, to a method for preventing soldering failure due to a terminal shift during mounting.

[0002]

2. Description of the Related Art As a connector, there is a connector for surface mounting which is directly mounted on a circuit board (printed board). FIG.
FIG. 2 is a perspective view of a conventional surface mount connector. The connector body 3 is attached to the printed circuit board 1.
To fix it to the printed circuit board 1.
A terminal 9 for connecting to a male connector (not shown) is provided in the connector body 3, and the terminal 9 is connected to the connector body 3.
Is connected to a conductive pattern (pad) (not shown) on the printed circuit board 1.

[0003] It is required that the connection portion 9a and the pad are connected with a certain strength. As an example of this type of terminal having an improved mounting strength, a terminal described in Japanese Utility Model Laid-Open No. 1-164673 is shown in FIGS.
It will be described based on. FIG. 5 is an enlarged perspective view of the terminal connection portion, FIG. 6 is a cross-sectional view of the connection portion on the pad, and FIG. 7 is a cross-sectional view of the soldered connection portion. As shown in FIG. 5, the connection portion 11a of the terminal 11 is formed in a wedge shape in which the surface facing the pad is narrow. As a procedure for surface mounting, cream solder 13 is applied to the printed circuit board 1 and the connector 11a is placed on the pad 15 to position the connector main body 3 (see FIG. 4). Next, after fixing the connector body 3 to the printed circuit board 1 using the screws 7 (see FIG. 4), the connector body 3 is passed through a not-shown reflow furnace to melt the cream solder 13, thereby completing the soldering (see FIG. 7). .

According to the terminal 11 described above, the connection 1
Since 1a is formed in a wedge shape, the amount of solder can be increased, and when a force in the separating direction is applied to the connection portion 11a and the pad 15, the force is applied to the boundary between the solder 13 and the connection portion 11a. , And the strength of soldering to the pad 15 could be increased as compared with the case where the connection portion 11a was simply formed in a rectangular cross section.

[0005]

However, in the conventional surface mount connector, when the screw 7 is tightened, the connector body 3 moves slightly, so that the connection portion 11a and the pad 15 are not moved.
The solder paste 13 applied to the printed circuit board 1
Was sometimes broken. If the cream solder 13 is disjointed, the amount of solder in each terminal will vary during soldering, and poor soldering will occur, causing a reduction in reliability. In the terminal 11, since the connecting portion 11a is formed in a wedge shape, the connecting portion 11a has a degree of freedom with respect to positional deviation.
Variation of the cream solder 13 due to the relative movement between a and the cream solder 13 could not be prevented. The present invention has been made in view of the above circumstances, and provides a surface mount connector capable of preventing variations in the amount of solder by eliminating variations in cream solder at the time of fixing the connector, thereby improving reliability. The purpose is to plan.

[0006]

According to a first aspect of the present invention, there is provided a surface mount connector having a structure in which cream solder is applied to a surface mount connector soldered to a pad on a circuit board. A bottom groove is formed on the lower surface of the connector body over the rear surface of the connector body, and one end side of the terminal formed in a U-shape is used as a tab,
The other end is a connection portion to the pad, the tab is fitted through a through hole formed in the rear surface of the connector body, and the connection portion is accommodated in the bottom groove. Times
It is characterized by being soldered to a pad on a circuit board .

[0007] While the tab of the terminal is fitted from the rear surface of the connector main body, the connection portion is accommodated in the bottom groove, and the terminal is positioned at a predetermined position. Cream solder is applied to the bottom groove, during attachment of the connector body, moving connecting portion and the pad relative, Barakeru it is not in the solder paste on the circuit board.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a surface mount connector according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a perspective view of a connector for surface mounting according to the present invention, and FIG. 2 is a sectional view of the connector for surface mounting of FIG. 4 and 6
The same reference numerals are given to the same members as those shown in FIG. Screw fastening portions 23 as fixing means are formed on both side surfaces of the box-shaped connector body 21 having an open front surface, and the screw fastening portions 23 are screwed with the screws 7 (see FIG. 4) to connect the connector body 21. It can be fixed to the printed circuit board 1. Rear surface 21a of connector body 21
Has a plurality of vertical grooves (hereinafter referred to as "terminal grooves").
25 are formed, and the terminal groove 25 is formed in the connector body 21.
Of the rear surface 21a. A plurality of bottom grooves (hereinafter, referred to as “cream solder grooves”) 27 are formed on the lower surface 21 b of the connector body 21, and the cream solder grooves 27 are connected to the terminal grooves 25 at the lower end of the rear surface 21 a. . That is, the connector main body 21 has a plurality of L-shaped grooves extending between the rear surface 21a and the lower surface 21b.

On the other hand, the terminal 29 is formed in a U-shape, and one end is a male tab 29a. Terminal 2
In 9, the male tab 29 a is projected into the connector main body 21 from the through hole 31 of the terminal groove 25. The other part of the terminal 29 from which the male tab 29a protrudes into the connector main body 21 is accommodated in the terminal groove 25 and the cream solder groove 27. In other words, the terminal 29 is configured so that the other end goes around the lower surface 21b. The terminal 29 is positioned at a predetermined position by the male tab 29a protruding into the connector main body 21 and the other portion being accommodated in the terminal groove 25 and the cream solder groove 27.

The other end of the terminal 29 is formed with a bent connecting portion 29b projecting outside the cream solder groove 27, and the connecting portion 29b has a spring property by being bent. Therefore, when the printed circuit board 1 is brought into contact with the lower surface 21b, the connecting portion 29b is pressed into the cream solder groove 27 and is pressed against the printed circuit board 1 by a spring force. Cream solder is applied to the cream solder groove 27 in which the connection portion 29b is accommodated. The cream solder is applied to the inside of the cream solder groove 27, so that it is protected from contacting foreign substances until melting. Connector body 21, terminal groove 25, cream solder groove 27, terminal 29
Is a main member or part, and the surface mounting connector 33 is configured.

The procedure for mounting the surface mounting connector 33 thus configured will be described. FIG. 3 is a cross-sectional view after mounting the surface mounting connector. Surface mount connector 3
To attach 3, first, the cream solder 13 is applied to the cream solder groove 27 of the connector body 21. Next, the connector main body 21 is positioned on the printed circuit board 1. As a result, the connection portion 29b at a predetermined position of the connector main body 21 is positioned with respect to the pad 15 on the printed circuit board 1.

After the positioning, the screw 7 inserted into the screw tightening portion 23 is screwed into the printed circuit board 1, so that the connector main body 21 is fixed to the printed circuit board 1. At this time, even if the connector body 21 moves, the cream solder 13 is in the cream solder groove 27, so that unlike the conventional structure in which the cream solder 13 is coated on the pads 15, the cream solder 13 It does not fall apart. Then, the printed circuit board 1 to which the connector main body 21 is fixed is passed through a reflow furnace, so that the cream solder groove 27 is formed.
The cream solder 13 in the inside is melted, and the connection portion 29b and the pad 15 in the pressed state are soldered.

The surface mount connector 3 according to the embodiment described above.
According to No. 3, the terminal 29 is accommodated in the terminal groove 25 and the cream solder groove 27 in addition to the fact that the object of the present invention can prevent the variation in the amount of solder due to the dispersion of the cream solder. The terminal 29 no longer projects from the connector 21, and the area occupied by the connector main body 21 on the printed circuit board 1 can be reduced. Further, the terminal 29 is positioned by being accommodated in the terminal groove 25 and the cream solder groove 27, and since the entire connecting portion 29b does not protrude, there is no deformation due to contact with foreign matter, and handling is easy. Becomes Further, in the surface mount connector 33 according to the above-described embodiment, the connection portion 29b and the pad 15 are soldered flat to each other, so that the soldering strength is remarkably higher than that of the conventional structure in which the connection portion has a wedge shape. Can be improved.

In the above embodiment, the terminal groove 2
5 and the cream solder groove 27 are both formed, but the connector body 21 may be formed with only the cream solder groove 27. Also in this case, the positioning of the terminal 29 is performed by the cream solder groove 27. Further, in the above-described embodiment, the case where the connector main body 21 is fixed by screws has been described as an example. However, the connector main body 21 projects other fixing means, for example, locking projections or bendable pins to the printed circuit board 1. Then, after passing through the connector main body 21, the pin may be bent to fix the connector main body 21.

[0015]

As described above in detail, according to the surface mounting connector of the present invention, since the cream solder is applied in the bottom groove, even if the connection portion and the pad relatively move,
The cream solder does not disperse on the circuit board, and the variation in the amount of solder can be prevented. As a result, the reliability of the soldered portion can be significantly improved. Further, in the case where the vertical groove is formed on the rear surface of the connector main body, the positioning is ensured and the terminal does not come into contact with the foreign matter, so that the risk of deformation and short circuit can be reduced. And if you give the connection part a spring property,
The pre-fixed state before soldering becomes better, and the strength and accuracy of soldering can be improved. Further, if the connector body is provided with the fixing means, the press-contact state of the connection portion is stably held, and the soldering can be performed more reliably.

[Brief description of the drawings]

FIG. 1 is a perspective view of a surface mount connector according to an embodiment of the present invention.

FIG. 2 is a sectional view of the surface mount connector of FIG. 1;

FIG. 3 is a cross-sectional view of the surface mounting connector of FIG. 1 after the board is mounted.

FIG. 4 is a perspective view of a conventional surface mount connector.

FIG. 5 is an enlarged perspective view of a terminal connecting portion in another conventional example.

6 is a cross-sectional view of the terminal connecting portion of FIG. 5 on a pad.

FIG. 7 is a cross-sectional view of the terminal connecting portion of FIG. 6 which is soldered.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printed circuit board (circuit board) 13 Cream solder 15 Pad 21 Connector body 21a Rear surface 21b Lower surface 23 Screw fastening part (fixing means) 25 Terminal groove (vertical groove) 27 Cream solder groove (bottom groove) 29 Terminal 29a Tab 29b Connection part 31 Through Hole 33 Surface Mount Connector

Claims (1)

(57) [Claims] 1. A surface mounting connector to be soldered and connected to pads on a circuit board, wherein a bottom groove to which cream solder is applied is formed on the lower surface of the connector main body over the rear surface of the connector main body. One end of the terminal formed as a tab is used as a tab, and the other end is used as a connection portion to the pad. The tab is inserted from a through hole formed in a rear surface of the connector body, and the connection portion is connected to the bottom groove. Housed in front
The connection is soldered to the pad on the circuit board in the bottom groove.
A connector for surface mounting.