Patent Publication Number: US-6213807-B1

Title: ZIF socket connector having improved contact arrangement

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a contact for a socket, and particularly to a contact for a ZIF socket. 
     2. Description of Prior Art 
     Referring to FIG. 1, a contact  6  for a ZIF socket generally comprises a base portion  61 , a connecting portion  62  connected to the base portion  61  and a body portion  63  extending from the connecting portion  62 . The base portion  61  forms a pair of fixing protrusions  611  on opposite edges thereof for being interferentially received in a housing  8  (see FIG. 3) whereby the base portions  61  are linearly aligned. The body portion  63  is U-shaped and forms a receiving portion  631  extending from the connecting portion  62  for receiving a pin  7  of a chipset (not shown) and a mating tail  632  extending from the receiving potion  631  for engaging with the pin  7 . 
     However, as shown in FIG. 2, when the pin  7  is moved to engage with the mating tail  632  of the contact  6  from the receiving portion  631 , a force f caused by resisting the movement of the pin  7  is exerted on the contact  6 . Thus, an accompanying moment for the force f is created but does not act on the center of mass of the contact  6 . Since the body portion  63  is U-shaped, a normal force from the mating tail  632  being exerted on the pin  7  is insufficient to maintain a stable contact resistance. Furthermore, the U-shaped body portion  63  does not promote the implementation of zero insertion force. Additionally, the linear alignment of interference between the base portions  61  of the contacts  6  and the housing  8  causes deformation of the housing. 
     SUMMARY OF THE INVENTION 
     Accordingly, an object of the present invention is to provide a contact for a ZIF socket having a pair of fixing protrusions lying in a plane which is substantially perpendicular to the direction of the movement of a pin of a chipset thereby preventing unwanted moment to the contact. 
     Another object of the present invention is to provide a contact for a ZIF socket having a simplified body portion while generating sufficient normal force between the contact engaged with the pin to maintain a stable contact resistance and promoting the implementation of zero insertion force. 
     Yet another object of the present invention is to provide a housing having contacts interferentially engaged therewith wherein the engagement force between adjacent rows of the contacts is not linearly aligned for thereby reducing deformation of the housing. 
     In order to achieve the objects set forth, a contact for a ZIF socket for electrically connecting with a pin of a chipset in accordance with the present invention, comprises a base portion, a connecting portion extending from the base portion, and a body portion extending from one side of the connecting portion. The body portion includes a receiving portion adapted for receiving the pin of the chipset located in a first position, and a mating portion extending from the receiving portion for sidewardly gripping the pin of the chipset when the pin is moved from the first position to a second position. The base portion has a pair of fixing protrusions on opposite edges thereof for interferentially engaging with a housing. An interferential direction between the fixing protrusions and the housing is substantially perpendicular to a movement direction of the pin from the first portion to the second portion. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other objects and advantages of the present invention will be understood from the following description of an electrical connector according to a preferred embodiment of the present invention shown in the accompanying drawings, in which; 
     FIG. 1 is a perspective view of a conventional contact for a ZIF socket including a pin of a chipset; 
     FIG. 2 is a top, planar view of FIG. 1 showing the pin engaging with the contact; 
     FIG. 3 is a top, planar view of the conventional contacts received in a housing; 
     FIG. 4 is a perspective view of a contact for a ZIF socket embody portioning the concepts of the present invention; 
     FIG. 5A is a top, planar view of FIG. 4 showing a pin of a chipset received in a receiving portion of the contact; 
     FIG. 5B is similar to FIG. 5A showing the pin engaged with the contact; and 
     FIG. 6 is a top, planar view of the contacts of the present invention received in a housing. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 4, a contact  1  for use with a ZIF socket in accordance with the present invention comprises a base portion  11 , a connecting portion  12  extending from a central portion of the base portion  11 , and a body portion  13  extending from the connecting portion  12 . The base portion  11  defines a pair of fixing protrusions  111  on opposite edges thereof for interferentially engaging with a housing  3  (see FIG.  6 ). A solder pad  112  extends from a bottom edge of the base  11  for electrically connecting with a printed circuit board (not shown). 
     The body portion  13  includes a receiving portion  131  extending from one side of the connecting portion  12  and a mating portion  132  extending from the receiving portion  131 . The receiving portion  131  is slightly bent for receiving a pin  2  of a chipset in a first position. The mating portion  132  is perpendicular to the connecting portion  12  for sidewardly gripping the pin  2  of the chipset when the pin  2  is moved from the first position to a second position. Thus, an interferential direction between the fixing protrusions  111  and the housing  3  is substantially perpendicular to a movement direction of the pin  2  from the first portion to the second portion. 
     Referring to FIGS. 5A and 5B, when assembling the chipset to the ZIF socket, the pin  2  of the chipset is first received in the receiving portion  131  in the first position, and is then moved to sidewardly grip the mating portion  132  in the second position. When the pin is moved from the first position to the second position, a force f caused by reactive movement of the pin  2  is exerted on the contact  1  substantially at the center of mass thereof. Thus, only a negligible moment is incurred. 
     Referring to FIG. 6, the ZIF socket includes the housing  3  and the contacts  1  received in the housing  3 . the housing  3  forms a plurality of cavities  31  each of which forms a fixing recess  32  in an end thereof for interferentially receiving the fixing protrusions  111  of the contact  1 . The fixing recesses  32  of adjacent cavities  31  are not aligned. Thus, the interferential engagement force between the contacts  1  of adjacent rows and the housing does not lie in plane whereby deformation of the housing  3  is minimized after insertion of the contacts  1 . 
     The spirit of the invention is to provide a housing defining an array of cavities  31  with the adjacent cavities  31  of the adjacent two rows being arranged in a diagonal direction and thus being offset from or not aligned with each other wherein the retention section, i.e., fixing protrusions  111  extend in an interferential direction perpendicular to the row direction defined by each row. Because of being offset from each other for the proximate cavities  31  of the two adjacent rows, the accumulated deformation of the housing due to interferential retention of the fixing protrusions  11  with the housing along the interferential direction may be reduced to only one half amount comparatively. 
     It will be understood that the present invention may be embodied in other specific forms without departing from the spirit of the central characteristics thereof. The present example and embodiment, therefore, is to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein.