Electrical socket connector with a load lever having self-biasing device

Provided herewith a land grid array socket comprises an insulative housing having a plurality of contacts and a metallic reinforce plate positioned at a bottom surface of the housing. The insulative housing has a top surface for receiving a land grid array package. A cover member is pivotally mounted on a first end of the insulative housing. The cover member is pivotal between an open position and a closed position where the cover member presses the land grid array package toward the top surface of the insulative housing so that the land grid array package electrically connects to the contacts. A lever, with an operating rod, is pivotally mounted on a second end of the insulative housing and has a tilted shaft portion biasing against the second end thereof so as to create a self-biasing elastic force with respect to the reinforce plate so that the lever, when set to a locked position, moves pivotally in a horizontal direction due to the elastic force to tightly engage with a latch of the reinforce plate to assure locking between the lever and the reinforce plate.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an electrical connector assembly for electrically connecting an electronic package such as a land grid array chip to a circuit board, and particularly to an electrical connector assembly with a load lever with self-biasing device. In use, the load lever is automatically biased toward a stiffener ensuring a more reliable engagement with the stiffener when the lever set to a locked position.

2. Description of the Related Art

Land Grid Array socket, has been widely used in personal computer (PC) system for connecting a CPU onto a printed circuit board (PCB), achieving the signal transferring between the CPU and the PCB, such as disclosed in Patent Issued U.S. Pat. No. 7,001,197 issued to Shirai, which teaches a LGA socket has an insulative housing receiving a plurality of contacts therein. A cover member is pivotally mounted on a first end of the insulative housing or a stiffener. The cover member is pivotal rotated between an open position in which the LGA chip can be disposed and a closed position to press the LGA chip toward the hosing. A load lever is pivotally mounted on a second end of the housing. The load lever has a locking portion for locking the cover in the closed position so as to ensure a reliable interconnection between the LGA chip and the connector. A metallic reinforcing plate is positioned on a bottom surface of the housing.

A typical conventional LGA socket20is shown inFIGS. 1 and 2. The connector comprises an insulative housing6, a metal stiffener7attached and surrounding the housing6, a cover8pivotally arranged at one side of the stiffener7, a load lever9is pivotally arranged on the other side of the stiffener7. The housing6also defines a plurality of passageways (not show) receiving a plurality of terminals (not show).

The stiffener7defines a rectangular cavity in the middle for retaining the housing therein, a first hinge71and a second hinge72are formed on a first end of the stiffener7, a connecting end73defined on the opposite to the first end, and a locking portion74is disposed in a side portion of the stiffener7thereof to engage with the arm portion941of the load lever9.

The cover8defines a joint portion81for connecting with the stiffener7, a hook82extending from the opposite end of the joint portion81.

The load lever9comprising a first axles portion91and a second axles portion92, a pressing portion93positioned between the first axles portion91and the second axles portion92, an arm portion941generally perpendicularly extending from the second axles portion92, and an operating portion extending from the distal end of the arm portion941.

In use, the pressing portion93can be pivoted through rotation to the operating portion942between horizontal and vertical position. The connector20is firstly in an open state with the cover8perpendicular to the housing6and the pressing portion93of the load lever9at a highest position. A LGA chip (not show) is then put into the housing6. Then the connector20is in a closed state. The cover8is rotated down and abutting the LGA chip. Rotate the load lever9with the pressing portion93pressing on the hook82and the arm portion941be locked in the locking portion74of the stiffener7. Thus the LGA chip is stably received in the connector20.

Because the first axles portion91and the second axles portion92which received in the first hinge71and the second hinge72are parallel to the first hinge71and the second hinge, gaps are formed between the first axles portion91and the first hinge71, and between the second axles portion and the second hinge during the connect in an open state and in a closed state, thus it is not compact enough between the load lever9and the stiffener.

A new electrical connector that overcomes the above-mentioned problem is desired.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a LGA socket with a load lever with self-biasing device. In use, the load lever is automatically biased toward a stiffener ensuring a more reliable engagement.

To fulfill the above-mentioned object, land grid array socket accordance with a preferred embodiment of the present invention comprising an insulative housing, a plurality of terminals received in the insulative housing, a metallic stiffener defining an opening for receiving the housing, a cover member and a load lever are respectively and pivotally mounted to the stiffener. The cover and the load lever are pivotal between an open and a closed position. The load lever with self-biasing device comprises a locking portion disposed between a first axles portion and a second axles portion, and an operational arm perpendicularly extending from the end of the second axles portion. When the load lever and the cover are in a closed position, the locking portion of the load lever pressing on one end of the cover. The self-biasing device causes the arm portion of the load lever automatically biasing toward the stiffener ensuring a reliable engagement.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

FIG. 3shows an exploded, isometric view of a land grid array socket100in accordance with a preferred embodiment of the present invention. The LGA socket100comprising an insulative housing2molded from resin or the like (hereinafter, simply referred to as “housing”). A stiffener3defining an opening (not labeled), the housing is positioned in the opening. A cover member4is pivotally mounted on a first end31of the stiffener3. A load lever5is pivotally arranged on a second end32of the stiffener3.

The individual elements of the LGA socket100will now be described in greater detail. The housing2is shaped in the form of a rectangular. A mating surface22is defined for mating a LGA package (not show). Conducting region21is defined in the center of the mating surface22receiving a plurality of terminals (not shown). Peripheral walls23extending upwardly from edges of the housing2.

The stiffener3for reinforcing the housing2defines a first end31, and the first end31defining a pair of pivot aperture (not labeled) to engage with the cover4. A second end32is defined on the opposite of the first end31. The second end32comprising a first hinge321and a second hinge322for receiving the load lever5. A locking portion33is formed in a side portion (not labeled) between the first end31and the second end32.

The cover member4is generally rectangular shape defining a generally rectangular frame43. A pair of engaging portions41is defined in one end of the cover4for engaging with the stiffener3, a hook42extending from the frame43on the opposite end to the engaging potions41.

The load lever5is formed by bending a single metallic wire and comprises a first axles portion51and a second axles portion52. A pressing portion53located between the first axles portion51and the axles portion52. The load lever5also has an arm portion541generally perpendicularly extending from the second axles portion52and an operational portion542extending and formed at the distal end of arm portion541. The load lever5has a self-biasing device at the first axles portion51and formed at an angle against to the second axles portion52. A protrusion511is formed on the first axles portion51.

Referring toFIGS. 3-5, in assembly process, the terminals are pre-loaded within the insulative housing2. The insulative housing2is then positioned in the opening of the stiffener3. The cover4is pivotably mounted to the first end31of the stiffener3. The load lever5is pivotably arranged in the second end32with the first axles portion51and the second axles portion52respectively received in the first hinge321and the second hinge322. The cover4and the load lever5are firstly in an open state, the LGA package is put onto the mating surface22of the housing2. When the cover4is closed, the pressing portion53pressing on the hook42, the arm portion541is engaged with the locking portion33of the stiffener3. During rotating the load lever5and hooking the arm portion541in the locking portion541, the protrusion511compactly attach on the first hinge321of the stiffener, and causing internal-stress between the protrusion511and the first hinge321. The internal-stress making the arm portion541biasing toward the stiffener. Thus, the self-biasing device of the load lever5ensuring more reliable engagement between the load lever5and the land grid array socket100.

Because the load lever5biasing towards stiffener3when the LGA socket is in a closed state, it causing stress between the arm portion541and the locking portion33to make more compactly connection.