Abstract:
An electrical connector ( 100 ) for electrically connecting an IC module to a printed circuit board includes a housing ( 1 ), a number of electrical contacts ( 2 ) received in the housing, a protecting device ( 3 ) floatable assembled with the housing, and an elastic device retained and sandwiched between the protecting device and the insulative housing. The contacts are divided into plural groups, each contact has an elastic contacting portion ( 221 ) projecting out of the housing. The protecting device can float up and down in a higher and lower positions, in the higher position the protecting device is supported by the elastic device, the contacting portions of the contacts are within the corresponding slots, and in the lower position the protecting device is pressed down, the contacting portions of the contacts project out of the slots.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The present invention relates to an electrical connector for electrically connecting a land grid array (LGA) integrated circuit (IC) to a printed circuit board (PCB).  
         [0003]     2. Description of Related Art  
         [0004]     An electrical connector used for electrically connecting an LGA electrical component to a PCB is widely applied in the field of electronics. A conventional electrical connector used for electrically connecting an LGA IC module to a PCB comprises an insulative housing defining a plurality of passageways for receiving a corresponding plurality of contacts. In additional, the insulative housing defines a matting surface for supporting the IC module. In order to obtain excellent elasticity for ensuring reliable electrical connection, each contact has a long elastic arm with a free end, and the free end is beyond the mating surface as a contacting portion of each contact. While the electrical connector is put into use, the IC module presses on the contacting portion to make the contact transform elastically. However, the contacting portions protrude from the mating surface, the contacting portion is easy to be bended or damaged by factors such as rough handling or accidental impact, which will weaken, even destroy, the electrical connection between the IC module and the connector.  
         [0005]     Thereby, an improved electrical connector is required to overcome the disadvantages of the prior art.  
       SUMMARY OF THE INVENTION  
       [0006]     An object of the present invention is to provide an electrical connector having a protecting device which can avoid the contacts of the electrical connector to be damaged.  
         [0007]     In order to achieve above-mentioned object, an electrical connector in accordance with a preferred embodiment of the present invention includes a housing, a number of contacts received in the housing, a protecting device floatable assembled with the housing, and an elastic device retained and sandwiched between the protecting device and the housing. The contacts are divided into plural groups, each contact has an elastic contacting portion projecting out of the housing. The protecting device can float up and down in a higher and lower positions, in the higher position the protecting device is supported by the elastic device, the contacting portions of the contacts are within the corresponding slots, and in the lower position the protecting device is pressed down, the contacting portions of the contacts project out of the slots.  
         [0008]     Other objects, advantages and novel features of the present invention will become more apparent from the following detailed description of the present embodiment when taken in conjunction with the accompanying drawings.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]      FIG. 1  is a simplified, exploded, perspective view of an electrical connector in accordance with the preferred embodiment of the present invention, showing a piece of protecting plate reversed;  
         [0010]      FIG. 2  is a partly assembled view showing housing-plates of  FIG. 1  assembled to form an insulative housing;  
         [0011]      FIG. 3  is an assembled view of the electrical connector of  FIG. 1   
         [0012]      FIG. 4  is a cross-section view taken along line  4 - 4  of  FIG. 3 , showing protecting plates of the electrical connector in a first position;  
         [0013]      FIG. 5  is a view similar to  FIG. 4 , but showing the protecting plates in a second position;  
         [0014]      FIG. 6  is an assembled view of the electrical connector assembling with a pick up cap. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0015]     Reference will now be made to the drawing figures to describe the present invention in detail.  
         [0016]     Referring to  FIG. 1 , an electrical connector  100  in accordance with the preferred embodiment of the present invention comprises an insulative housing  1 , a plurality of contacts  2  to be received in the housing  1 , a protecting device  3  for protecting the contacts  2 , and elastic device for linking the protecting device  3  and the housing  1 . Springs  4  are chose for acting as the elastic device in this embodiment.  
         [0017]     The insulative housing  1  comprises four pieces of separated housing-plates  1   a ,  1   b ,  1   c ,  1   d . As each piece of housing-plate  1   a ,  1   b ,  1   c ,  1   d  is much smaller than a conventional single-piece housing, it will suffer a littler warp during the cooling course after it is molded. Therefore flatness and reliability of the insulative housing  1  can be controlled more easily. The four housing-plates  1   a ,  1   b ,  1   c ,  1   d  are of the same structure, we will refer to the housing-plate  1   c  to be typical of all the housing-plates  1   a ,  1   b ,  1   c ,  1   d  to describe their structure. Each housing-plate has a shape of rectangle and comprises a first end  11 , a second end  12  and a middle portion  10  therebetween. The middle portion  10  of each housing-plate defines a plurality of passageways  105  in rows and columns (only partially shown) for receiving the electrical contacts  2 . The middle portion  10  has a first upper surface and a first lower surface, the passageways  105  extend through the first upper and lower surfaces.  
         [0018]     At the middle portion  10  adjacent to the two ends  11  and  12  respectively, there are a rim  104  protruding from outer edges thereof, a pair of first blind holes  102  for accommodating one ends of the springs  4 , and a latching hole  103  between the first blind holes  102 . The first blind holes  102  communicate with the first upper surface and block in the first lower surface. Additionally, an ear  101  projects outwardly from the middle point of a longitudinal edge of the middle portion  10 . The ear  101  defines a latching hole therethrough.  
         [0019]     The two ends  11  and  12  are both thinner than the middle portion  10 , the first end  11  has a bottom surface upper than that of the middle portion  10  and the second end  12  has a top surface lower than that of the middle portion  10 . The first end  11  defines a binding hole  112  and a first aligning hole  111 . The second end  12  has a binding tab  122  and a second aligning hole  121 .  
         [0020]     Referring to  FIGS. 1 and 2 , the four pieces of housing-plates  1   a ,  1   b ,  1   c ,  1   d  are joined end by end. Now, a process how to join the housing-plate  1   a  with other two housing-plates  1   b  and  1   d  will be described as an example. The housing-plates  1   a  and  1   b  are disposed in a position that they are perpendicular to each other. Then the first end  11   a  of the housing-plate  1   a  is overlapped onto the second end  12   b  of the housing-plate  1   b , together to make up a thickness proximate to that of the middle portion  10 , while the first aligning hole  111   a  aligning with a second aligning hole  121   b  to form a unitary hole  14 , and the binding tab  122   b  being received in the binding hole  112   a  to bind the two plates  1   a ,  1   b . As the binding tab  122   b  has a diameter slightly larger than that of the binding hole  112   a , the two plate  1   a ,  1   b  are toughly assembled together after the binding tab  122   b  is forced into the binding hole  112   a . Alike, the housing-plates  1   a  and  1   d  are joined in a similar way, that the second end  12   a  of the housing-plate  1   a  is overlapped to the first end  12   d  of the housing-plate  1   d  with the second aligning hole  121   a  aligning with the first aligning hole  111   d  and the binding tab  122   a  received within the binding hole  112   d.    
         [0021]     The contacts  2  are arranged in the insulative housing  1  in rows and columns. Each contact  2  comprises a main body  21  retained in the passageways  105 , a spring arm  22  extending upwards along an inclined direction beyond the first upper surface, and a soldering portion  23  extending downwards and projecting out of the first lower surface. The spring arm  22  has a curved free end as a contacting portion  221  to electrically connect with the IC module. The contacts  2  are divide into many rows or groups in array. In a row or group, the spring arms  22  of the contacts are parallel to each other and incline along a same direction in a fictitious plane which is perpendicular to the first upper surface of the insulative housing  1 . Shadows of neighboring spring arms of the contacts in a row partially overlap on the first upper surface of the housing.  
         [0022]     The protecting device  3  floatable assembles with the insulative housing  1 , comprises four pieces of protecting plates  3   a ,  3   b ,  3   c ,  3   d  corresponding to the four pieces of housing-plates  1   a ,  1   b ,  1   c ,  1   d . Each protecting plate respectively corresponds to and assemblies with each housing-plate. The four pieces of protecting plates are of the same structure, as shown in  FIG. 1 , the protecting plate  3   c  is introduced as an example as below. The protecting plate  3   c  has a shape of rectangle which similar to the shape of the housing-plates, and comprises a pair of middle latching members  32  and a pair of end latching members  33  downwardly protruding thereof. The latching members  32 ,  33  are respectively corresponding to the latching holes of the housing-plates. The protecting plate  3   c  has a second upper surface and a second lower surface opposite to each other. At each end the protecting plate  3   c  defines a pair of second blind holes  34 , correspond to the first blind holes  102  of the housing-plates, for accommodating the other ends of the springs  4 . The second blind holes  34  communicate with the second lower surface and block in the second upper surface.  
         [0023]     In additional, the protecting plate  3   c  defines a plurality of parallel slots  31  which extend through the second upper and lower surfaces and extend along a breadth direction perpendicular to the longitudinal direction of protecting plate  3   c . Each slot  31  corresponds to a row of contacts  2  along the breadth direction and provides a free space for the corresponding group of contacts during the protecting device floating up and down. Along extending direction of corresponding slots a plurality of notches  311  are formed to communicate with corresponding slots  31  at the edge of the second upper surface.  
         [0024]     Referring to  FIG. 3 , the protecting device  3  assembles with the insulative housing together to form the electrical connector  100 , in assembly, the latching members  32 ,  33  of the protecting device  3  engage with the latching holes  103  of the insulative housing  1 , and the springs  4  sandwiched therebetween with elastic force, two free ends of each spring  4  respectively received in the corresponding blind holes  34 ,  102  of the protecting device  3  and the insulative housing  1 . The protecting plates  3   a ,  3   b ,  3   c ,  3   d  of the protecting device  3  are respectively parallel to the housing-plate  1   a ,  1   b ,  1   c ,  1   d  of the insulative housing  1 , and shown in  FIG. 4 , a space is defined between the first upper surface of the insulative housing  1  and a second lower surface of the protecting plate  3 . Thus, if loading or unloading a sufficient external force, the protecting device  3  can float down and up without breaking off the insulative housing  1 .  
         [0025]     As shown in  FIGS. 3-4 , in a first position, the electrical connector  100  is unused to electrically connect an IC module, the protecting device  3  is spaced from the insulative housing  1 , and the contacting portions  221  of the contacts  2  project out of the first upper surface of the insulative housing  1 , but not project out of the second upper surface of the protecting plates of the protecting device  3 . The contacting portions of the contacts  2  in one row are accommodated within one slot  31  of the protecting plates, and the spring can resist a certain external force and assure the contacts  2  should not be damaged. Thus, while the assembled electrical connectors  100  are left unused, being storied or carried, the protecting device  3  is supported by the springs  4  in the first position to prevent the spring arms  22  from accidental damage.  
         [0026]     In a second position, as shown in  FIG. 5 , a sufficient external force loaded on the protecting plate  3 , the space eliminates between the protecting plate  3  and the insulative housing  1 , the contacts  2  are still in a relaxed manner, but the contacting portions  221  of the contact  2  project out of the slot  31  and the second upper surface of the protecting plate  3 . When the electrical connector  100  is to electrically connect to the IC module, the protecting device  3  needn&#39;t to be removed, the IC module can be directly press on the protecting device  3  and make it float down, and the spring arms  221  of the contacts  2  in a same slot  31  are pressed to grovel towards the corresponding notches  311 , finally, the IC module is fixed on the protecting plate  3  and electrically connect with the contacting portions  221  of the contacts  2 . If removing the IC module, the springs  4  can provide an elastic force to urge the protecting device  3  from the second position to the first position.  
         [0027]     Moreover,  FIG. 5  shows a pick up cap  5  to be assembled to the electrical connector  100 . The pick up cap  5  comprises a flat plate  51  defining a circle of through holes  52  therein, and four retention posts  53  respectively extending down from four corners of the flat plate  51  to be received in the unitary hole  14  of the housing  1  to retain the pick up cap  5  to the electrical connector  100 .  FIG. 5  shows the pick up cap  5  being assembled to the electrical connector  100 . During transmitting of the electrical connector  100 , the pick up cap can be catch up by a cupule. Thus, in virtue of the pick up cap  5 , the electrical connector  100  can be picked up conveniently.  
         [0028]     The disclosure is illustrative only, changes may made in detail, especially in matter of shape, size, and arrangement of parts within the principles of the invention.