Land grid array socket with improved fastening structure

1. Field of the Invention

The present invention relates to an electrical connectors, and more particularly to an land grid array (LGA) socket for electrically connecting two electrical interfaces, such as an LGA package and a printed circuit board (PCB).

2. Description of the Prior Art

An LGA socket is used to electrically connect an LGA package and a printed circuit board. Referring to FIG. 1 to FIG. 2 , an LGA socket typically comprises an insulative housing 10 , a plurality of contacts 11 received in the insulative housing 10 , a stiffener 12 positioned on a bottom surface of the insulative housing 10 , a load plate 13 mounted on a first end of the stiffener 12 to partially cover the insulative housing 10 and a lever 14 mounted on the second end of a stiffener 12 to lock the load plate 13 to the stiffener 12 . The lever 14 comprises an actuating portion 141 and a retaining portion 142 perpendicular to the actuating portion 141 . A pair of openings 121 , which are spaced apart from each other, are formed in the second end of the stiffener 12 for supporting the retaining portion 142 of the lever 14 . A latch portion 122 is formed on one side of the stiffener 12 for locking the actuating portion 141 in a closed position. A middle of the retaining portion 142 has a locking section 1420 to press a bearing tongue 131 of the load plate 13 in order to lock the load plate 13 to the stiffener 12 .

However, as well known that the printed circuit board has many electrical elements, thus, during the process of the lever 13 and the load plate 14 opening to two sides of the LGA socket, there will generate interference with other electrical elements disposed on the printed circuit board.

To prevent deformation of the lever and the load plate of the LGA socket and the interference with other electrical elements, U.S. Pat. No. 7,207,822 issued to Szu on Apr. 24, 2007 discloses another type of LGA socket, in which the lever is attached to the load plate by a tongue extending from the load plate to form a hook. This type of LGA socket may be convenient to assemble the LGA socket and mount an LGA package thereon. However, the lever mounted on the load plate is not secure. Therefore, improvement may be needed.

One particular aspect of the present invention is to provide a fastening structure and a land grid array (LGA) socket using the fastening structure. The LGA socket using the fastening structure is used to electrically connect an LGA package to a printed circuit board.

In order to achieve the object set forth, a fastening structure comprises a stiffener including a first end and a second end opposite to the first end. A load plate is pivotally supported on a first end of the stiffener and has a pair of lateral walls. A lever is pivotally mounted on the lateral walls of the load plate and a locking portion to lock the load plate to the stiffener. An LGA socket using the fastening structure comprises an insulative housing having a plurality of contacts. A stiffener includes a first end and a second end and is positioned on a bottom surface of the insulative housing. A load plate is pivotally attached on the first end of the stiffener and has at least a lateral sidewall. A lever is pivotally mounted on the lateral sidewall, the lever and the load plate is being pivotal between an open position and a closed position together, the lever has a transverse locking portion to lock the load plate to the stiffener near the second end of the stiffener.

For further understanding of the invention, reference is made to the following detailed description illustrating the embodiments and examples of the invention. The description is only for illustrating the invention and is not intended to be considered limiting of the scope of the claim.

FIG. 1 is an exploded view of a conventional LGA socket;

FIG. 2 is an assembled view of FIG. 1 ;

FIG. 3 is an exploded view of an LGA socket in accordance with a preferred embodiment of the present invention;

FIG. 4 is an assembled view of the LGA socket of FIG. 3 , wherein a load plate with a lever attached thereto is oriented to an opening position; and

FIG. 5 is an assembled view of the LGA socket of FIG. 3 , wherein the load plate with the lever attached thereto is oriented to an closed position.

Reference will now be made to the drawings to describe the present invention in detail.

Referring to FIG. 3 to FIG. 4 , an LGA (Land Grid Array) socket 5 in accordance with a preferred embodiment of the present invention is used to electrically connect an LGA package 4 and a printed circuit board (not shown). The LGA socket 5 comprises an insulative housing 50 having a plurality of contacts 51 received therein and a stiffener 52 disposed around the housing 50 . A load plate 53 is pivotally attached to the stiffener 52 and rotatable relative to the stiffener 52 between an opening position and a closed position. A lever 54 is pivotally mounted on the load plate 53 for pressing and successively locking the load plate 53 in the close position.

Individual elements of the LGA socket 5 will now be described in greater details. Referring to FIG. 3 , the insulative housing 50 is molded from resin or the like and is shaped in form of a rectangular planar board. The housing 50 has an electric region defining a plurality of passages thereof to receive the plurality of contacts 51 therein. The LGA package 4 and the printed circuit board form an electrical connection therebetween via the contacts 51 received in the LGA socket 5 .

The stiffener 52 is a rectangular metal frame located along with an periphery of the housing 50 . The stiffener 52 has a first end 522 for attaching the load plate 53 , a second end 523 opposite to the first end 522 and a pair of sidewalls 524 respectively and integrally connecting the first end 522 and the second end 523 . The first end 522 defines a pair of latching slots 5220 spaced apart from each other. The second end 523 forms a shaft support piece. The shaft support piece includes a curved portion 5231 bent upwardly from the stiffener 52 and a curved tongue 5232 bowing inward from the curved portion 5231 for holding the lever 54 . A latch portion 5240 is integrally formed on one of the sidewalls 524 near the first end 522 . The bottom of the stiffener 52 defines four holes (not numbered) at the corners thereof to secure the LGA socket 5 on the printed circuit board. In alternative embodiments, the stiffener 52 can be two separate parts, served as a first end 522 and a second end 523 . That is to say, the stiffener 52 can be broken or omitted.

The load plate 53 is shaped in form of a rectangular planar board 534 and has an opening 530 in a middle area thereof. The load plate 53 comprises a connecting side 532 to be connected to the first end 522 of the stiffener 52 , a press side 533 corresponding to the second end 523 of the stiffener 52 , and a pair of lateral sidewalls 531 vertically bent from the load plate 53 for jointing the connecting side 532 to the press side 533 . The connecting side 532 forms a pair of curved latches 5320 pivotally inserted into the latching slots 5220 of the stiffener 52 . The load plate 53 has a pair of holes 5310 on the lateral sidewalls 531 near the press side 533 for pivotally receiving the lever 54 . The load plate 53 forms a pair of downwardly curved press sections (not labeled) on the opposite sides of the opening 530 of the load plate 53 for pressing the LGA package 4 evenly. On the press side 533 of the load plate 53 , there is a slot 5312 at the middle of a free end adapted to conveniently assemble the lever 54 to the load plate 53 .

The lever 54 is bent from a metal bar. The lever 54 is L-shaped and comprises an actuating portion 541 with a curved actuating arm 5410 and a retaining portion 542 that is perpendicular to the actuating portion 541 . The retaining portion 542 has a transverse locking portion 5421 that is positioned in the middle of the retaining portion 542 and is offset outside from the axis of the retaining portions 542 with a pair of inclined sections (not labeled) connecting the transverse locking portion 5421 and a pair of rotary portions 5422 of the retaining portion 542 . The retaining portion 542 is arranged in the holes 5310 of the load plate 53 and secured on the tail end by a clasp 55 .

In assembly, the retaining portion 542 of the lever 54 is pivotally received in the holes 5310 of the load plate 53 . The stiffener 52 is assembled to the housing 50 before or after the load plate 53 mounted on the stiffener 52 .

Referring to FIG. 4 , the load plate 53 with the lever 54 is attached in an opening position. Actuation of the lever 54 moves the load plate 53 and the lever 54 between an opened position and a closed position together.

Referring to FIG. 5 , it discloses the LGA package 4 is mounted in the housing 50 and the LGA socket 5 is in the closed position. The transverse locking portion 5421 of the lever 54 is locked by the tongue 5232 of the stiffener 52 . The actuating portion 541 is latched by the latch portion 5240 .

Although the present invention has been described with reference to particular embodiments, it is not to be construed as being limited thereto. Various alterations and modifications can be made to the embodiments without in any way departing from the scope or spirit of the present invention as defined in the appended claims.