JP3225347B2 - 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 connector mounted on an electronic device or the like by soldering to a wiring board, and more particularly to a connector suitable for use in an environment where repetitive temperature changes are large.

[0002]

2. Description of the Related Art Conventionally, a connector shown in FIG. 6 is known as this kind of connector. This connector 1 is a housing 1
1 and a plurality of contacts 12. The housing 11 is formed in a box shape by an insulating material,
A fitting recess 11a for receiving a mating connector is opened on the upper surface. The contact 12 is formed of a conductive material, and is held through the bottom wall 11 b of the housing 11. At one end, a contact portion 12a is located in the fitting concave portion 11a of the housing 11 and comes into contact with a contact (not shown) of the mating connector. The other end protrudes from the bottom surface of the housing and is soldered to the wiring board. Terminal portion 12b.

FIG. 7 is a cross-sectional view showing a state where the above-described connector 1 is mounted on a wiring board 2. As shown in the figure,
The connector 1 is inserted into a through hole 2 a formed in the wiring board 2 by projecting the terminal 12 b protruding from the bottom surface of the connector 1, and the terminal 12 b protruding from the back side of the wiring board 2 is soldered to the printed board 2. It is electrically and mechanically connected and fixed on the wiring board 2.

FIGS. 9A and 9B are a perspective view and a sectional view showing a state in which another conventional connector is mounted on a wiring board. The connector 3 is of an SMT type in which a plurality of contacts 32 project from a side surface of a housing 31 at predetermined intervals. When the connector 3 is mounted on the wiring board 4, the lower end of the contact 32 is placed on the wiring board 4 as shown in FIG.
Soldered.

[0005]

However, when the connector 1 is used in an environment where the temperature is repeatedly changed, as shown in FIGS. 7 and 10, the thermal expansion coefficients of the housings 11 and 31 and the wiring boards 2 and 4 are reduced. Due to the difference, a relative displacement Δ1 is generated between the contact penetrating holding portion at a distance of D from the center line C in the longitudinal direction L of the housings 11 and 31 and the contact soldering portion of the wiring board, and the contacts 12 and 32 are the same. The state changes from the upright state shown by the solid line to the collapsed state shown by the dotted line. When this is repeated, the contact 1 is attached to the soldered portions 2b and 4b of the contact.
Repeated stress acts through the solder cracks 2c and 2c due to thermal fatigue destruction as shown in FIGS.
4c is generated, and the connection strength with the wiring board may be reduced, or in the worst case, poor electrical continuity may occur, resulting in a defect that connection reliability is lacking. This became remarkable as the positions of the soldering portions 2b and 4b of the contacts 12 and 32 became farther from the center line C of the housings 11 and 31.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks, and prevents solder cracks due to thermal fatigue destruction even when used in an environment with a large temperature change, prolongs the life of the connector and mounts the connector. An object of the present invention is to provide a connector capable of preventing a failure of an electronic device.

[0007]

SUMMARY OF THE INVENTION The present invention comprises a housing,
In a connector that is arranged along a predetermined direction of the housing and includes a plurality of contacts each soldered to a wiring board, the contact has a contact portion connected to a mating connector on one end and a contact spring piece on the other end. A contact body provided with a socket portion having a socket, and one end inserted into the housing and one end inserted into the housing to elastically contact the contact spring piece of the socket portion movably in the arrangement direction of the contacts, and from the housing. The protruding other end comprises a terminal portion for soldering to the wiring board. In the connector of the present invention configured as described above, the contact body fixed to the housing and the terminal portion soldered to the wiring board side when the connector is used in an environment where the temperature changes repeatedly are large. While being resiliently contacted with each other by the contact spring pieces of the socket portion, the housing and the wiring board move corresponding to a relative displacement due to a difference in thermal expansion coefficient between the housing and the wiring board. As a result, since the contact is prevented from falling down due to the relative displacement, there is no fear that stress acts on the soldered portion via the contact unlike the conventional example, and a connector that prevents the occurrence of solder cracks due to thermal fatigue destruction is provided. it can.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing a state in which the connector of the present invention is mounted on a wiring board, and FIG. 2 is an exploded perspective view of a contact. That is, the connector 5 includes a rectangular parallelepiped housing 51 and a plurality of contacts 52 disposed along the longitudinal direction of the housing 51.

The contact 52 includes a contact body 53,
It comprises a pin-shaped terminal portion 54 connected to the contact body 53. The terminal portion 54 has a prismatic shape with both ends formed in a pyramid shape. One end is inserted into the through hole 2 a of the wiring board 2 and soldered, and the other end is connected to the contact body 53. The contact main body 53 is formed by pressing a conductive metal plate to form a plate-shaped contact portion 53a that contacts a mating contact (not shown) on the front end side.
A socket 53b into which the terminal 54 is inserted is provided at the rear end.
Is provided. The socket part 53b is a contact body 53
By bending the rear end side of the contact body 53,
Are formed in the shape of a rectangular tube having both ends opened in the axial direction, and the inner dimensions thereof are set to dimensions in which the terminal portions 54 are inserted with a gap. The socket portion 53b is provided with a contact spring piece 53d on an upper wall surface 53c facing a bottom wall surface 53e continuous with the contact portion 53a. The contact spring piece 53d is on the upper wall surface 5.
3c is cut and raised so as to gradually approach the bottom wall surface 53e from the rear end side to the bottom wall surface 53e.
The portion between 3 e extends until it becomes smaller than the outer dimensions of the terminal portion 54. The housing 51 is formed of an insulating material into a rectangular parallelepiped box shape, and has an upper surface with a fitting recess 51a into which a mating connector is fitted. Fitting recess 5
A plurality of through-holes 51b for fixing the contact body of the contact 52 are provided on the bottom wall of the housing 1a at regular intervals in the longitudinal direction of the housing 51. The through-hole 51b is opened in the fitting concave portion 51a, and the socket portion 5 of the contact body 53 is formed.
A press-fit hole 51c for press-fitting 3b, and an insertion hole 51d that is open to the bottom surface side of the housing 51 and that is inserted into the terminal portion 54 and that is continuous with the press-fit hole 51c.

Next, in order to assemble the connector 5, first, the contacts 52 are inserted from the side where the mating connector is fitted.
The socket portion 53b of the contact body 53 is inserted into the fitting concave portion 51a of the housing 51 with the through hole 5b.
The socket part 53b is fixed to 1b. At this time, the socket portion 53b changes the bending direction of the contact spring piece 53d to the contact 5
2 is pressed into the press-fitting hole 51c of the through-hole 51b in a direction perpendicular to the arrangement direction. Thereafter, by inserting one end of the terminal portion 54 into the insertion hole 51d from the bottom surface of the housing 51, the terminal portion 54 is fitted into the socket portion 53 through the insertion hole 51d, and the contact spring piece 53d of the socket portion 53 is elastically displaced. It is tightly fitted between the contact spring piece 53d and the bottom wall surface 53e of the socket portion 53b, and is held by the housing 51 with the other end protruding downward from the bottom surface of the housing 51. When the terminal portions 54 are incorporated into the housing 51, the terminal portions 54 are incorporated in a state where they are aligned by a location jig corresponding to the arrangement pitch of the through holes 2a of the wiring board 2.

Next, in order to attach the connector 5 to the wiring board 2 as shown in FIG.
The terminal portion 54 protruding from the bottom surface of the housing 51 is inserted into the housing 51, and the mounting holes 51e provided at both ends of the housing 51 are aligned with the mounting holes 2c formed on the connector mounting surface of the wiring board 2. Next, the screw member 55 is connected to the wiring board 2.
The nut 56 is screwed into the screw member 55 protruding from the rear surface through the mounting holes 51e and 2c from the front side. Thereafter, the connector 5 is electrically and mechanically connected and fixed on the wiring board 2 by soldering the terminal portion 54 projecting to the back surface through the through hole 2a.

When the connector 5 mounted as described above undergoes repeated temperature changes, the contact body 53 fixed to the housing 51 and the terminal portion 54 fixed to the wiring board 2 are brought into contact with the contact spring piece of the socket portion 53b. 53d in a state where the housing 51 and the wiring board 2 are elastically contacted with each other by the difference in thermal expansion coefficient between the housing 51 and the wiring board 2.
1 in the longitudinal direction. As a result, since the relative displacement is not directly transmitted to the terminal portion 54 side, stress is applied to the terminal portion 54.
On the soldering portion 2b between the wiring board 2 and the wiring board 2.

Next, FIG. 4 is a graph showing the degree of occurrence of cracks in the connector 5 of the present invention in comparison with the connector 1 of the prior art. In the figure, the dotted line indicates the degree of occurrence of cracks in the connector 5, and the solid line indicates the degree of occurrence of cracks in the connector 1. As shown in the figure, the maximum amount of cracks is shown at both ends of the housing (in FIG. To). As is clear from the comparison of the figures, in the connector 5 of the present invention shown by the dotted line, the degree of crack generation can be reduced, and the thermal fatigue life is improved accordingly.

Although the present invention has been described with reference to the case where the terminal portion 54 of the contact 52 is inserted into the through hole 2a formed in the wiring board 2 and soldered, the present invention is applied to the SMT type connector 6 as shown in FIG. The same can be applied to the above. It is not necessary to arrange all the contacts 52 in the longitudinal direction of the housing, and the contacts 52 may be arranged only at both ends of the housing where the soldered portion is greatly damaged and in the vicinity thereof.

[0015]

As described above, according to the connector of the present invention, the contact is divided into two parts, the contact body and the terminal part, the contact body is attached to the housing side, and one end of the terminal part is attached to the wiring board side. In the housing, the other end side of the terminal portion is elastically contacted with the contact spring piece of the contact body so as to be movable in the arrangement direction of the contacts.

For this reason, when the use environment temperature repeatedly changes greatly, the contact body and the terminal portion are in elastic contact with each other in accordance with the relative displacement between the housing and the wiring board due to the difference in thermal expansion coefficient between the housing and the wiring board. Move with. This makes it difficult for the relative displacement to be transmitted to the terminal portion side.
Stress acting on a soldered portion between the terminal portion and the wiring board is reduced.

As a result, it is possible to provide a connector in which the life of the soldered portion is extended and the reliability after soldering and mounting on the wiring board is improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a state in which a connector of the present invention is mounted on a wiring board.

FIG. 2 is an exploded perspective view of a contact in the connector of the present invention.

FIG. 3 is an explanatory view showing a state in which the connector of the present invention is mounted on a wiring board.

FIG. 4 is a graph showing the state of occurrence of solder cracks in the connector according to the embodiment of the present invention and the conventional connector.

FIG. 5 is a sectional view showing a connector according to another embodiment of the present invention mounted on a wiring board.

FIG. 6 is a perspective view of a conventional connector.

FIG. 7 is a cross-sectional view showing a state where a conventional connector is mounted on a wiring board.

FIG. 8 is an enlarged cross-sectional view illustrating a state of occurrence of solder cracks in the connector of FIG. 7;

9A is a perspective view of another conventional connector mounted on a wiring board, and FIG. 9B is a cross-sectional view of FIG. 9A.

FIG. 10 is an explanatory diagram of a solder mounting state of the connector of FIG. 9;

FIG. 11 is an enlarged perspective view illustrating a state of occurrence of solder cracks in the connector of FIG. 10;

[Explanation of symbols]

 1,5 Connector 11,51 Housing 12,52 Contact 53 Contact body 53a Contact part 53b Socket part 53d Contact spring piece 54 Terminal part

Claims (1)

(57) [Claims] 1. A connector comprising: a housing; and a plurality of contacts arranged along a predetermined direction of the housing and each of which is soldered to a wiring board. A contact body provided with a contact spring piece on the other end side is arranged and fixed to the housing. A contact body is inserted into the housing at one end side and is resiliently movable in the contact arrangement direction of the contact on the contact spring piece of the socket part. A connector comprising a terminal portion which is brought into contact with the other end and protruded from the housing and soldered to the wiring board.