Abstract: A CPU socket comprises a base (10) defining a plurality of passageways (111) therethrough and a pair of recesses (123) in a bottom surface thereof, a plurality of contacts (50) received in the corresponding passageways, a cover (20) defining a plurality of holes (211) in alignment with the passageways of the base and a pair of slits (223) in an upper surface thereof corresponding to the pair of recesses of the base, and a pair of retention member (40) each having a securing portion (41) retained in the cover and an elastic engaging portion (43) received in the recess of the base. When the cover moves between an open position where the pins of the CPU are disconnected from the conductive contacts of the base and a closed position where the pins of the CPU are connected with the conductive contacts of the base, the elastic engaging portion moves in the recess of the base while preventing the cover form separating the base.

Abstract: A ZIF socket (1) includes a base (10) having a plurality of passageways (100) for receiving a corresponding number of contacts (20) therein, a cover (12) having a corresponding number of holes (125) in alignment with the corresponding passageways, and a lever (14) assembled between the base and the cover for driving the cover to move along the base. The base includes a retention member (163) and the cover includes a supporting surface (1231) and a slot (165) to cooperate with the retention member. Both of the retention member and the supporting surface are disposed for efficiently fastening the cover and the base together.

Abstract: A ZIF socket assembly used with a package (6) comprises a ZIF socket (5), an actuating tool (8) and a protector (7). The socket comprises a base (51) and a sliding cover (53). The base comprises a recess (514) at an end thereof. The sliding cover is moveable assembled on the base for mounting the package and comprises a slot (533) in alignment with the recess. The protector is placed on the package and comprises a number of legs (71) extending downwardly for pressing against edges of the package. A contacting portion (73) extends outwardly from an edge of the protector and has a guiding face (75). The actuating tool is inserted into the recess through the slot and is rotatable from an initial, inclined position to a final, vertical position to drive the cover, the package and the protector to move with respect to the base.

Abstract: An electrical connector (1) mounted on a circuit board (5) comprises an insulative housing (2) with a number of terminals (3) retained therein, and a pair of board locks (4) downwardly extending from the housing. Each board lock includes a connecting portion (41) integrally connecting with the housing, a hook (42) formed at a free end of the connecting portion for engaging with a bottom face (53) of the circuit board, and a rib (43) projecting from the connecting portion in a direction opposite to the extending direction of a free end (420) of the hook for abutting against an inner wall (502) of a corresponding through hole (50) of the circuit board.

Abstract: An electrical connector has improved contacts for electrically connecting pins of an external electrical device with a printed circuit board. The contact includes a base portion, a receiving portion, and a tail portion. The receiving portion has two head portions and two spring arms. One bent line is defined between the spring arm and the head portion. Another bent line is defined between the spring arm and the base portion. The receiving portion is bend along the two bent lines to achieve pin receiving and engaging function.

Abstract: A socket comprises a first base having a plurality of solder balls attached to a bottom thereof and a second base. A cam lever is rotatably received in the second base and has a handle portion extending to exterior of the second base for operation of the cam lever. A cover is slidably mounted on the first base and the second base and fixes the first base and the second base in a juxtaposed relation.

Abstract: A method for positioning a solder ball onto a contact tail of an electrical connector comprises several steps. Firstly, arrange the contact tail into a center region and a peripheral region surrounding the center region. Secondly, attach solder paste onto the center region of the contact tail via a first mesh painting procedure. Thirdly, attach solder resist onto the peripheral region of the contact tail via a second mesh painting procedure. Fourthly, position a solder ball on the center region of the contact tail via a screen board. Fifthly, apply a reflow soldering procedure on the solder ball so that the solder ball can be soldered on the solder paste attached to the center region of the contact tail.

Abstract: A fixing device comprises a first locking member, a second locking member and a pair of locking nuts. The first locking member includes a base portion, four engaging posts and a pair of positioning posts. A pair of platforms is formed on lateral ends of the base portion. Each platform forms a locking hole for receiving corresponding locking nut. Rotation of the locking nut is limited by the platform to ensure proper positioning of a cap of the locking nut. The engaging posts equidistantly extend from the base portion, and each engaging post forms a circular neck. Each positioning post downwardly extends from the corresponding platform, and has a hollow body communicating with the receiving hole. A slot is formed in each positioning post. The positioning post has an upper portion defining a hole having a diameter larger than that defined by a lower portion of the positioning post. A subulate portion is formed at a bottom end of each positioning post for engaging with the circuit board.

Abstract: An electrical connector includes a dielectric base plate in which steel and copper strips are embedded. The steel and copper strips are respectively arranged in opposite sides of the base plate substantially perpendicular to and interconnected to each other whereby when the base is subject to a heating process, the steel and copper strips limit and control thermal expansion in different directions of the base plate and reduce differences in thermal expansion between the base plate and a circuit board to which the connector is mounted. Furthermore, a method for achieving substantially uniform thermal expansion of a dielectric plate is also provided and comprises the steps of (1) providing a dielectric plate made by injection molding and (2) fixing steel and copper strips thereto for limiting and controlling the expansion of the plate in different directions to achieve substantially uniform thermal expansion of the plate.

Abstract: A ZIF socket connector includes a base defining a plurality of pin receiving holes and a cover slidably positioned on the base and defining a plurality of through holes corresponding to the pin receiving holes. Conductive pins of a chip to be mounted on the connector extend through the through holes of the cover and into the pin receiving holes of the base. Each pin receiving hole has a conductive terminal fixed therein. Each terminal has a resilient arm imparting a transverse engaging force on the corresponding pin upon engaging therewith. Some of the terminals are fixed to a first inside face of the pin receiving holes, while the remaining terminals are located at an opposite second inside face of the pin receiving holes whereby the transverse engaging forces acting on the two groups of pin receiving holes are opposite to and thus cancelled by each other.

Abstract: A locking mechanism is used in a pin grid array socket which comprises a movably housing and a stationary housing. The locking mechanism comprises a cam lever having a handle bar connected to a cam which is pivotally connected to the stationary housing and operative to drive the movable housing to move in opposite directions. An elongated channel is defined along the handle bar. A first reception groove is formed in the movable housing. A latch is movably and rotatably received in the elongated channel. A head of the latch is movably inserted into the first reception groove for locking the cam lever and preventing the movable housing from movement.

Abstract: The present invention relates to a method for adjusting differential thermal expansion between an electrical socket and a circuit board by means of secure and accurate interconnection of an adjusting device therebetween before a heating step. The adjusting device is made of an adhesive fusible material and fixed to the housing for absorbing most of the fracture stress exerted on the solder balls and for eliminating a misalignment between the electrical socket and the circuit board during the heating step. The adjusting device can be designed according to practical requirements to be a number of adjusting posts, an adjusting frame, or an adjusting chip.

Abstract: A fine pitch contact for a ZIF socket in accordance with a first embodiment of the present invention comprises a base for being fixed in the socket, a tail for being connected to a PCB, and a curved twisted body upwardly extending from the base. The body is twisted about a central line thereof and acts as both a lead-in portion and an engaging portion to reduce the size thereof thereby promoting an increase in the density of the contacts of the ZIF socket. In accordance with a second embodiment of the present invention, a fine pitch contact for a ZIF socket comprises a base, a tail and a body. The body comprises a first bent portion formed proximate a free end thereof and a second bent portion formed by bending out of the plane of the body along an oblique bend line. The first and the second bent portions respectively perform a lead-in function and an engaging function to reduce the size of the body.

Abstract: An electrical connector for electrically connecting a chip module to a circuit board comprises a dielectric base, a dielectric cover, a number of contacts and a positioning member. Each contact comprises a contact portion received in the base and a joining portion extending into the positioning member. The positioning member has a number of guiding holes and a number of conical receiving recesses having solder balls deposited therein. The guiding holes of the positioning member snugly receive the joining portions of the corresponding contacts thereby preventing molten solder from flowing into the base. The positioning member may be made of the same dielectric material as the mating circuit board thereby eliminating different thermal expansion between top and bottom surfaces of the solder balls due to a difference in coefficients of thermal expansion between the electrical connector and the mating circuit board.

Abstract: A retention mechanism includes a frame and a pair of fixing devices. The fixing device includes a pair of locking screws and an engaging member. The locking screw forms a circular head and a conical threaded post. The engaging member includes a base pad and a pair of locking silos formed on lateral sides of the base pad. The locking silos are received in corresponding holes of a circuit board and the receiving holes of the retention mechanism, and the locking screw is inserted into a hole of the locking silo. Thus, the locking silo is expanded by the conical threaded post and an engaging force is provided between the locking silo and the circuit board. Therefore the retention mechanism is securely fixed to the circuit board.

Abstract: An electrical connector adapted for connecting with a chip comprises a housing and a number of contacts. The housing defines a number of cavities therein. Each cavity is formed with a pair of ribs extending from an inner surface of the cavity along an insertion direction of the contacts. Each contact is received in the corresponding cavity of the housing and abuts against the positioning device for preventing deflection thereof.

Abstract: An electrical contact for use with a BGA socket comprises an engaging section and a connecting section attached thereto. The connecting section comprises a circular solder plate attached directly below an elongate body of the engaging section thereby providing the contact with increased durability. The engaging section is inserted into the corresponding passageway of the housing from a bottom surface thereof whereby the circular solder plate effectively covers an opening of the passageway. Flux is applied to the solder plates of the contacts by means of a screening process and the contacts will not deform under pressure of a squeegee. A solder ball is attached to the solder plate and positioning mechanism ensures that the solder ball adheres to a central portion thereof.

Abstract: An electrical connector comprises a base defining a plurality of elongate channels and a plurality of alternating first and second cavities in each channel, a cover movably attached to the base and a plurality of first and second contacts respectively received in the first and second cavities of the base. Each contact comprises a retention portion, a spring arm extending from one edge of the retention portion, and a mounting portion laterally extending from an opposite edge of the retention portion. The spring arm forms an engaging portion at a free end thereof comprising first and second connecting portions deflecting from a plane of the retention portion. The contacts are assembled to the base with the engaging portions of the adjacent contacts being offset a distance smaller than a dimension of a pin of an electronic chip, causing alternating contacts to electrically engage with alternating pins on opposite sides thereof.

Abstract: A socket for providing electrical connection between an IC and a mother board comprises an insulative housing defining a number of terminal passageways and a number of terminals received in the passageways. Each terminal includes a contact portion, a securing portion, an adjustment portion and a soldering portion. The contact portion is adapted to engage a pin of the IC. The securing portion is interferentially fit in the passageway for retaining the terminal therein. The feature of the invention lies in the resilient adjustment portion which can be easily and resiliently deformed.

Abstract: An electrical connector includes an insulative housing defining a plurality of cavities therein, a number of contacts and an arrangement for strengthening the engagement of the connector to a circuit board. The strengthening arrangement includes a number of holes disposed along an outer periphery of the cavities and a number of terminals received in the holes. Each of the contact and the terminal has a mating portion and a mounting portion. The mounting portions of the contacts and the terminals are connected to the contact pads of the circuit board by solder balls. A stress exists when the contacts and terminals are soldered to the contact pads on the circuit board, but the stress acting on the contacts is relieved by the terminals sharing a lot of the stress. Thus, the contacts are secured on the contact pads.