Abstract:
Disclosed is an electrical connector ( 20 ) for connecting an IC package ( 30 ) having a mating surface ( 302 ) and a number of pins ( 300 ) and guiding walls ( 316 ) extending past the mating surface. The electrical connector includes a base ( 200 ) defining a number of passages ( 2040 ). A number of terminals ( 230 ) are set in the corresponding passages, respectively. A cover ( 210 ) defining a number of through-holes ( 214 ) in accordance with the passages and guiding slots ( 216 ) in compliance with the guiding walls is movably mounted on the base. A cam ( 220 ) is provided to drive the cover to move relative to the base. When the guiding walls of the IC package are inserted into the guiding slots, the pins of the IC package remain a distance away from the through-holes of the cover.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention generally relates to the art of electrical connectors and, more particularly to an electrical connector having positioning mechanism. 
   2. Background of the Invention 
   Integrated circuit (IC) packages are generally classified as pin grid array (PGA) packages, ball grid array (BGA) packages and land grid array (LGA) packages depending on shape of the conductive elements. 
   Electrical connectors for removably connecting an IC package and a substrate, such as a printed circuit board (PCB), are correspondingly defined as PGA connectors, BGA connectors and LGA connectors. 
   An electrical connector typically includes an insulative housing defining a plurality of passages and a plurality of terminals residing in the corresponding passages, respectively. In use, conductive elements of the IC package, i.e. pins of the PGA package or soldering pads of the BGA package or conductive pads of the LGA package, are brought to contact with the corresponding terminals and, therefore, electrical connection between the IC package and the electrical connector is established. 
   To ensure performance of the electrical connector, the conductive elements of the IC package should be properly registered with the terminals. However, in use, the IC package may be difficult to be accurately positioned on the electrical connector and, therefore, the conductive elements of the IC package are likely to be displaced with respect to the corresponding terminals. As a consequence, it is possible that electrical connection between the IC package and the electrical connector may be adversely affected. 
   Therefore, there is a heretofore unaddressed need in the industry to address the aforementioned deficiencies and inadequacies. 
   SUMMARY OF THE INVENTION 
   According to a first preferred embodiment of the present invention, an electrical connector is used to electrically connect an IC package having a mating surface and a number of pins and guiding walls extending past the mating surface along a common insertion direction. The electrical connector includes a base defining a number of passages. A number of terminals are disposed in the corresponding passages, respectively. A cover defining a number of through-holes in accordance with the passages and guiding slots in compliance with the guiding walls is movably mounted on the base. A cam is provided to drive the cover to move with respect to the base between an open position and a closed position. When the guiding walls of the IC package are inserted into the guiding slots along the insertion direction, the pins of the IC package remain a distance away from the through-holes of the cover. 
   During the course of assembling the IC package on the electrical connector, the guiding walls begin to mate with the guiding slots prior to the mating of the pins of the IC package and the through-holes of the cover. Thus, the IC package may be accurately set on the electrical connector. 
   According to a second preferred embodiment of the present invention, an electrical connector is used for electrically connecting an IC package having a plurality of pins and positioning projections extending along a common insertion direction. The electrical connector includes an insulative housing having a supporting surface and a number of cavities extending from the supporting surface. A number of contacts are planted in the corresponding cavities, respectively. The insulative housing is provided with a number of positioning grooves in compliance with the positioning projections of the IC package. When the positioning projections mate with the positioning grooves along the insertion direction, the pins of the IC package are spaced apart from the supporting surface. 
   In course of mounting the IC package on the electrical connector, the positioning projections begin to mate with the positioning grooves prior to mating of the pins of the IC package and the cavities of the insulative housing. Consequently, the IC package may be accurately positioned on the electrical connector. 
   Other features and advantages of the present invention will become more apparent to those skilled in the art upon examination of the following drawings and detailed description of preferred embodiments, in which: 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  depicts an exploded, isometric view of an electrical connector and an IC package in accord with a first preferred embodiment of the present invention; 
       FIG. 2  depicts a bottom view of the IC package shown in  FIG. 1 ; 
       FIG. 3  depicts a bottom view of assembly of the electrical connector and the IC package shown in  FIG. 1 , wherein a cover of the electrical connector is oriented to an open position; 
       FIG. 4  is similar to  FIG. 3 , but shown the cover of the electrical connector been oriented to a closed position. 
       FIG. 5  depicts an exploded, isometric view of an electrical connector and an IC package according to a second preferred embodiment of the present invention; 
       FIG. 6  depicts a bottom view of the IC package shown in  FIG. 5 ; and 
       FIG. 7  depicts a side view of the electrical connector shown in  FIG. 5 , wherein positioning projections of the IC package begin to mate with positioning grooves defined in the electrical connector. 
       FIG.8  depicts an exploded, isometric view of another alternative form of the electrical connector and an IC package in the first preferred embodiment of the present invention, wherein the grooves only extend through the cover but do not extend into the base; 
       FIG.9  depicts an assembled view of an alternative form of the electrical connector assembly shown in  FIG. 1 , wherein second guiding slots are configured to only partially extend along thickness of the base. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Reference will now be made to describe the preferred embodiments of the present invention in detail. 
   As shown in  FIG. 1  to  FIG.4  and  FIG.8 , an electrical connector  20  in accord with a first preferred embodiment of the present invention is used for electrically connecting an IC package  30  and a PGB (not shown). 
   Individual elements of the electrical connector  20  will now be described in greater detail. As shown in  FIG. 1 , the electrical connector  20  includes a base  200  having a plurality of terminals  230 . A cover  210  is rested on the base  200 . The cover  210  is movable with respect to the base  200  between an open position and a closed position. An actuating element, for example a cam  220 , is provided at one side of the base  200  and the cover  210 . The cam  230  is used to actuate the cover  210  to move along the base  200  between the open position and the closed position. 
   The cover  210  is molded from resin or the like and is shaped in the form of a rectangular planar board. A first rectangular opening  212  is defined in a center of the cover  210 . A plurality of through-holes  214  extending throughout the cover  210  is defined at opposite sides of the first rectangular opening  212 . Two pairs of first guiding slots  216  generally configured to an L-shaped configuration are provided at peripheral side of the through-holes  214 . One of the first guiding slots  216  has a shape different from those of other&#39;s, for example a flattened corner, so as to assure the correct mate of the IC package  30  and the electrical connector  20 . Alternatively, the first guiding slots  216  may take on other shapes, for example a columnar or post shape. A first chamber  219  is defined at one side of the cover  210 . 
   In the present embodiment of the invention, the first guiding slots  216  are configured to extend throughout the cover  210 . In an alternative form, the first guiding slots  216  may be designed to only partially extend along thickness of the cover  210 . For example, referring to  FIG. 8 , the grooves  216  only extend into the cover  210  but do not extend into the base  200 . In this case, there is no need to correspondingly define second guiding slots  206  in the base  200 . 
   The base  200  is molded from resin or the like and is shaped in the form of a rectangular planar board. The base  200  defines a second rectangular opening  202  in a center thereof. The second rectangular opening  202  is sized and shaped in compliance with the first rectangular opening  212 . A plurality of cavities  2040  extending throughout the base  200  is defined at opposite sides of the second rectangular opening  202  in a matrix pattern. The cavities  2040  are disposed in accord with the through-holes  214  of the cover  210 . A second chamber  209  consistent with the first chamber  219  is defined at one side of the base  200 . 
   Referring to  FIGS. 1–4  and  FIG. 9 , in another embodiment of the present invention, two pairs of second guiding slots  206  in compliance with the first guiding slots  216  are defined in the base  200 . The second guiding slots  206  may be configured to only partially extend along thickness of the base  200  or extend throughout the base  200 . The second guiding slots  206  are slightly wider than the first guiding slots  216  so that the movement of the cover  210  between the open position and the closed position is allowed. 
   A plurality of terminals  230  is planted in the corresponding cavities  2040 , respectively. Each of the terminals  230  includes a contacting section (not numbered) to contact with a pin  300  of the IC package  30  and an opposite soldering section (not numbered) to be connected to the PCB via a soldering ball  308  attached thereon. 
   The cam  220  includes a head  222 , a connecting section  224  extend downward from the head  222  and a mounting section  226  for fastening the cam  220 . The head  222  generally takes on a columnar configuration. A slot  228  is defined in the head  222  so that driving tools can be inserted therein to actuate the cam  220 . A base ring  205  is provided to fasten the cam  220  to the base  200  and the cover  210 . In another embodiment of the present invention, other actuating element, such as a driving lever, may also be applied to actuate the cover  210  to move with respect to the base  200 . 
   As best shown in  FIG. 2 , the IC package  30  has a mating surface  302  to mate with the cover  210 . A radiator section  304  is formed at a center of the IC package  30 . The radiator section  304  protrudes upward beyond the mating surface  302 . A plurality of pins  300  extends upward from the mating surface  302  to define a pin area  306 . The pins  300  are disposed consistent with the through-holes  214  of the cover  210  and the cavities  2040  of the base  200 . A plurality of guiding walls  316  is formed at peripheral side of the pin area  306 . The guiding walls  316  are defined in accord with the first guiding slot  216  of the cover  210  and the second guiding slot  206  of the base  200 . The guiding walls  316  extend upward further with respect to tips of the pins  300 . 
   Assembly of the electrical connector  20  will now be described in greater detail. As shown in  FIG. 1 , the terminals  230  are positioned in the corresponding cavities  2040 , respectively. The cover  210  is mounted on the base  200 . The first rectangular opening  212  is situated in compliance with the second rectangular opening  202 . The through-holes  214  are registered with the cavities  2040 . The first chamber  219  is located corresponding to the second chamber  209 . The cam  220  is inserted into the first chamber  219  and the second chamber  209  in sequence and tightened to the cover  210  and the base  200  via the base ring  205 . 
   Operation of the electrical connector  20  will now be described in greater detail. As best shown in  FIG. 3  and  FIG. 4 , in use, the cover  210  is oriented to the open position. The guiding walls  316  of the IC package  30  are plugged into the corresponding first guiding slots  216  of the cover  210 . The IC package  30  is further pressed and the pins  300  thereof are inserted into the corresponding through-holes  214  of the cover  210 , respectively. When the pins  300  are in a fully inserted position, the guiding walls  316  is situated within the guiding slots  206 ,  216 . 
   The cam  220  is actuated to actuate the cover  210 , together with the IC package  30  assembled thereon, to move with respect to the base  200  to the closed position. In the closed position, the pins  300  of the IC package  30  are brought to contact with the terminals  230  residing in the cavities  2040 . Thus, electrical connection between the IC package  30  and the electrical connector  20  is obtained. 
   During the course of mounting the IC package  30 , the guiding walls  316  begin to mate with the first guiding slots  216  prior to mating of the pins  300  of the IC package and the through-holes  214  of the cover  210 . Therefore, pins  300  may be accurately inserted into the through-holes  214 . 
   Additionally, in use, when the IC package  30  is securely mounted on the electrical connector  20 , the engagement of the guiding walls  316  and the guiding slots  206 ,  216  may prevent the IC package  30  from being displaced with respect to the electrical connector  20  under extreme shock or vibration at a sudden. 
   As shown in  FIG. 5  through  FIG. 7 , an electrical connector  40  in accord with a second preferred embodiment of the present invention is used to electrically connect an IC package  60  and a PCB (not shown). 
   Individual elements of the electrical connector  40  will now be described in greater detail. As shown in  FIG. 5 , the electrical connector  40  includes an insulative housing  400  defining a plurality of passageways  406  and a plurality of contacts  500  received in the corresponding passageways  406 , respectively. 
   The insulative housing  400  is molded from resin or the like and is shaped in the form of a rectangular planar board. The insulative housing  400  includes a supporting surface  402  to support the IC package  60 , a mounting surface  404  mountable on the PCB, and a plurality of passageways  406  extending between the supporting surface  402  and the mounting surface  404  in a matrix pattern. The insulative housing  400  is formed with a plurality of standoffs  410  projecting from the mounting surface  404 . A rectangular opening  405  is defined in a center of the insulative housing  400 . 
   Two pairs of positioning grooves  408  are defined at peripheral side of the passageways  406 . The positioning grooves  408  are configured to an L-shaped configuration. One of the positioning grooves  408  has a shape different from those of other&#39;s, for example a flattened corner, so as to assure proper mating of the IC package  60  and the electrical connector  40 . Alternatively, the positioning grooves  408  may take on other shape, for example a columnar or post shape. In the present embodiment, the positioning grooves  408  are configured to extend throughout the insulative housing  400 . In an alternative form, the positioning grooves  408  may also be designed to only partially extend along thickness of the insulative housing  400 . 
   A plurality of contacts  500  is positioned within the corresponding passageways  406 , respectively. Each of the contacts  500  includes a contacting section (not numbered) to contact with a pin  600  of the IC package  60  and an opposite soldering section (not numbered) to be connected to the PCB via a soldering ball  508  attached thereon. 
   As best shown in  FIG. 6 , the IC package  60  has a mating surface  602  to mate with the electrical connector  40 . A plurality of pins  600  extends upward from the mating surface  602 . The pins  600  are disposed consistent with the passageways  406  of the insulative housing  400 . A plurality of positioning walls  608  is formed at peripheral side of the pins  600 . The positioning walls  608  are defined in accord with the positioning grooves  408  of the insulative housing  400 . A radiator section  604  is formed at a center of the IC package  60 . The radiator section  604  protrudes upward beyond the mating surface  602 . 
   Assembly and operation of the electrical connector  40  will now be described in greater detail. As shown in  FIG. 5  and  FIG. 7 , the contacts  500  are inserted into the corresponding passageways  406  from one side of the mating surface  402  and the mounting surface  404 , respectively. In use, the positioning walls  608  of the IC package  60  are plugged into the corresponding positioning grooves  408  of the insulative housing  400 , respectively. The pins  600  of the IC package  60  are further inserted into the corresponding passageways  406  and brought to contact with the contacts  500 , respectively. When the pins  600  are in a fully inserted position, the positioning walls  608  are situated within the positioning grooves  408 . 
   During the course of mounting the IC package  60 , the positioning walls  608  begin to mate with the positioning grooves  408  prior to the mating of the pins  600  of the IC package  60  and the passages  406  of the insulative housing  400 . Therefore, pins  600  may be accurately inserted into the passageways  406 . 
   Additionally, in use, when the IC package  60  is securely mounted on the electrical connector  40 , the cooperation of the positioning walls  608  and the positioning grooves  408  may prevent the IC package  60  from being displaced with respect to the electrical connector  40  under extreme shock or vibration. 
   It should be understood that the positioning of the IC package  60  on the electrical connector  40  may be realized in other manners. For example, in an alternative form, the positioning walls may be integrally formed with the insulative housing  400 , and the positioning grooves may be correspondingly defined in the IC package  60 . The IC package  60  may also be accurately positioned on the electrical connector  40  as long as the positioning walls begin to mate with the positioning grooves prior to the mating of the pins  600  and the passageways  406 . 
   While the present invention has been described with reference to specific embodiments, the description of the invention is illustrative and is not to be construed as limiting the invention. Various of modifications to the present invention can be made to the preferred embodiments by those skilled in the art without departing from the true spirit and scope of the invention as defined by the appended claims.