Patent Document

BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an apparatus for removing an electrical component from contact with a substrate. More specifically, the present invention relates to an apparatus integratable with a socket connector assembly for extracting an electrical component from the socket connector assembly. 
     2. Brief Description of Earlier Developments 
     Socket connector assemblies help secure electrical components, such as integrated circuit (IC) chips, to substrates. An array of pins typically extend from the electrical components. The pins can have any arrangement, including a standard pin grid array (PGA) or an interstitial pin grid array (PZA). 
     One such socket connector assembly is a low insertion force (LIF) assembly. In a LIF assembly, an array of press-fit sockets reside in openings in the insulator housing. The placement of the sockets corresponds to the locations of the pins on the electrical component. The pins of the electrical component are inserted into the sockets for mating. While offering low insertion forces, these assemblies require an extraction force to remove the electrical component from the socket assembly. The force required to extract the electrical component from the socket increases as the number of pins on the electrical component increases. 
     In order to remove the electrical component from the LIF assembly, current techniques require a separate extraction tool. The special tool grasps the edges of the electrical component for extraction. The use of the extraction tool has several potential disadvantages. First, the user must have the special extraction tool available. Second, the forces imposed on the edges of the electrical component by the tool may damage the electrical component. 
     Clearly, there is room for improvement in the art. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide an apparatus for removing an electrical component from contact with a substrate. 
     It is a further object of the present invention to provide an apparatus for extracting an electrical component from a socket connector assembly. 
     It is a further object of the present invention to provide an apparatus integratable with a socket connector assembly. 
     It is a further object of the present invention to provide an apparatus that removes an electrical component from contact with a substrate without damage to the electrical component. 
     It is a further object of the present invention to provide an apparatus that distributes forces on a larger area of an electrical component when removing the electrical component from contact with a substrate. 
     It is a further object of the present invention to provide a self-contained apparatus for removing an electrical component from contact with a substrate. 
     It is a further object of the present invention to provide an apparatus that removes an electrical component from contact with a substrate without assistance from a special extraction tool. 
     These and other objects of the present invention are achieved in one aspect of the present invention by an extraction tool comprising: an insulative housing; an electrical component receiving surface for receiving the electrical component thereon; and a socket contacting surface for engaging the socket. Movement of the apparatus generally along the socket also moves the apparatus in a direction generally away from the socket to extract the electrical component from the socket. 
     These and other objects of the present invention are achieved in another aspect of the present invention by a socket for receiving an electrical component have conductive elements. The socket has an insulative housing; a plurality of apertures extending through the housing and corresponding to the conductive elements of the electrical component; and an extraction device engaging surface adapted to engage an extraction device for removing the electrical component from the apertures. 
     These and other objects of the present invention are achieved in another aspect of the present invention by a kit including a socket and an extraction device. The kit attaches an electrical component having conductive elements to a substrate in an insertion axis. The socket has a plurality of apertures corresponding to the conductive elements of the electrical component. The extraction device moves relative to the socket between a first position and a second position. The extraction device includes a receiving surface for engaging the electrical component. At the first position, the extraction device allows the conductive elements of the electrical component to reside within the apertures of the socket. At the second position, the extraction device withdraws the conductive elements of the electrical component from the apertures of the socket. 
     These and other objects of the present invention are achieved in another aspect of the present invention by a method of extracting an electrical component from a socket connector assembly, comprising the steps of: providing a socket connector assembly having a socket; and an extraction device engageable with the socket; providing an electrical component on the socket connector assembly; and moving said extraction device relative to said socket. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other uses and advantages of the present invention will become apparent to those skilled in the art upon reference to the specification and the drawings, in which: 
     FIG. 1 is a perspective view of one alternative embodiment of the present invention; 
     FIG. 2 is an exploded, cross-sectional view taken along lines II—II in FIG. 1; 
     FIG. 3 is an exploded, cross-sectional view of an alternative arrangement of the first alternative embodiment of the present invention; 
     FIG. 4 is a cross-sectional view of a portion of the first alternative embodiment of the present invention; 
     FIG. 5 is a plan view of one component of the first alternative embodiment of the present invention; 
     FIG. 6 is a perspective view of a second component of the first alternative embodiment of the present invention; 
     FIG. 7 is a detailed view of a portion of FIG. 2 appearing in the dashed circle; 
     FIG. 7 a  is a cross-sectional view of the alternative embodiment of the terminal appearing in FIG. 3; 
     FIG. 7 b  is a cross-sectional view of another alternative embodiment of a terminal of the present invention; 
     FIG. 8 is a perspective view of another alternative embodiment of the present invention; 
     FIG. 9 is an exploded, cross sectional view taken along lines IX—IX in FIG. 8; 
     FIG. 10 is a perspective view of one component of the second alternative embodiment of the present invention; 
     FIG. 11 is a perspective view of a second component of the second alternative embodiment of the present invention; and 
     FIG. 12 is a plan view of an alternative arrangement for the second alternative embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIGS. 1-12 display several alternative embodiments of the present invention. Generally speaking, the present invention is a socket connector assembly that couples an electrical component E to a substrate S, such as a printed circuit board. The assembly also has features that assist in the extraction of electrical component E from the socket connector assembly. 
     The socket connector assembly has integratable two parts, a socket housing and a slide. The socket housing mounts to substrate S and has an array of apertures that receive conductive elements, such as pins P, extending from electrical component E. The socket housing also has structure that interacts with corresponding structure on the slide to help extract electrical component E from the socket connector assembly. 
     The slide engages the socket housing and supports the electrical component. The slide includes structure corresponding to the structure on the socket housing. Movement of the slide across the housing helps extract electrical component E from the socket connector assembly. More specifically, as the slide is moved across the socket housing, the structures on the slide and on the socket housing interact to direct electrical component E away from substrate S along the insertion axis. 
     In other words, the corresponding structure on the socket housing and the slide interact to transform some of the movement of the slide across the housing (from a mating position to an extraction position) into a displacement of the slide away from substrate S along the insertion axis. Since electrical component E rests at least partially on the slide, the displacement of the slide also urges electrical component E away from substrate S along the insertion axis. This helps extract pins P from the terminals. The corresponding structure will now be described in detail. 
     A detailed discussion of each alternative embodiment of the socket connector assembly of the present invention follows. FIGS. 1-7 display a first alternative embodiment of the present invention. 
     A socket connector assembly  100  couples electrical component E to substrate S. Assembly  100  includes an integratable socket housing  101  and a slide  103 . Socket housing  101  can be generally planar and made from a suitable insulative material. Socket housing  101  has a mounting end  105  that faces substrate S and a mating end  107  that faces electrical component E. 
     Electrical component E partially rests on mating end  107  of housing  101 . The remainder of electrical component E rests on slide  103 . Apertures  109  extend between mounting end  105  and mating end  107  of housing  101 . Apertures  109  receive pins P of electrical component E. 
     Conductive terminals  111  reside within apertures  109 . Terminals  111  can remain in apertures  109 , for example, by an interference fit. Terminals  111  electrically connect component E to substrate S. 
     The present invention interposes slide  103  between housing  101  and electrical component E. Slide  103  helps extract component E from housing  101 . Extraction occurs due to the interaction of corresponding structure on both housing  101  and slide  103 . 
     Slide  103  can be generally planar and made from any suitable insulative material. Slide  103  has a mating end  113  that faces electrical component E and a mounting end  115  that faces housing  101 . Electrical component E rests on mating end  113 . Mounting end  115  rests on housing  101 . 
     Slide  103  moves on housing  101  between a mating position and an extraction position along the arrow shown in FIGS. 2 and 3. In the mating position, slide  103  rests on housing  101  so as to avoid interference with the mating of pins P of electrical component E with terminals  111  on housing  101 . In the extraction position, slide rests on housing  101  in such a position that pins P of electrical component E cannot mate with terminals  111  of housing  101 . Therefore, manipulation of slide  103  across housing  101  from the mating position to the extraction position disengages pins P from terminals  111 . 
     The corresponding structure on housing  101  and slide  103  helps extract electrical component E from socket connector assembly  100 . The corresponding structure on housing  101  and slide  103  interact to transform some of the movement of slide  103  across housing  101  in the direction of the arrow in FIGS. 2 and 3 (from the mating position to the extraction position) into a displacement of slide  103  away from substrate S along the insertion axis. Since electrical component E partially rests on slide  103 , the displacement of slide  103  also urges electrical component E away from substrate S along the insertion axis in order to extract pins P from terminals  111 . The corresponding structure will now be described in detail. 
     Housing  101  and slide  103  can have interfitting notches  117  and projections  119 . The location of projections  119  within notches  117  determines the mated height of socket connector assembly  100 . When projections  119  fully nest within notches  117  as shown in FIG. 4, slide  103  is in the mating position. As an example, a peak  121  of projection  119  abuts a valley  123  of notch  117  when slide  103  is in the mating position. In the mating position, pins P can mate with terminals  111 . Socket connector assembly  100  exhibits its lowest mated height in the mating position. This assists the interaction of pins P and terminals  111 . 
     As slide  103  moves across housing  101  along the arrow shown in FIG. 2 and 3 from the mating position towards the extraction position, projections  119  withdraw from the fully nested position. As projections  119  withdraw, the mated height of socket connector assembly  100  increases as shown in phantom in FIG.  4 . The mated height eventually increases enough to prevent pins P from mating with terminals  111 . In other words, as slide  103  moves across housing  101  along the direction of the arrow shown in FIGS. 2 and 3, slide  103  extracts pins P from terminals  111  of housing  101 , eventually removing pins P from contact with terminals  111 . Slide  103  attains the extraction position, for example, when peak  121  of projection  119  approaches a peak  125  of notch  117 . At the extraction position, pins P cannot mate with terminals 
     Notches  117  and projections  119  can have a triangular cross-section, although other shapes could be used. With triangular cross-sections, a major surface  127  of projection  119  slides along a major surface  129  of notch  117  as seen in FIG.  4 . Slide  103  moves from its mating position to its extraction position along the direction of the arrow in FIGS.  2  and  3 . In the mating position, a minor surface  131  of projection  119  abuts a minor surface  133  of notch  117  as seen in FIG.  4 . 
     The inclination of major surfaces  127 ,  129  causes the increase in mated height of socket connector assembly  100  as slide  103  moves from its mating position to its extraction position. As stated above, socket connector assembly  100  displays its smallest mated height when projections  119  fully nest within notches  117 . The mated height of socket connector assembly  100  increases as projection  119  travels along inclined major surface  129  of notch  117 . 
     The first alternative embodiment of the present invention accommodates an electrical connector in which its pins extend around only the periphery, leaving the central portion devoid of any pins. FIG. 5 displays housing  101  capable of receiving peripherally located pins P on electrical component E. Apertures  109  reside around the periphery of housing  101 , while notches  117  occupy a central location on mating end  107  of housing  101 . 
     Slide  103  rests on housing  101 . In order to avoid interference with apertures  109 , slide  103  has a smaller peripheral extent than housing  101 . Except for the portion of slide  103  seen in FIG. 1, which is described below, slide  103  resides beneath electrical component E and rests on housing  101 . 
     Notches  117  and projections  119  preferably extend in a direction across the width of housing  101  and slide  103 , respectively. Stated differently, notches  117  and projections  119  extend in a direction that is perpendicular to the movement direction of slide  103  (shown as the arrow in FIGS.  2  and  3 ). 
     Due to the peripheral location of apertures  109 , notches  117  do not extend across the entire width of housing  101 . In other words, notches  117  only extend across the central portion of housing  101 . This creates a wall  169  at the interface between the peripheral area and the central portion of housing  101 . Wall  169  abuts side walls  171  of slide  103  to ensure proper alignment of slide  103  in housing  101  as slide  103  moves from its mating position to its extraction position. 
     In order to move slide  103  across housing  101 , slide  103  has a tab  141  extending from a leading edge  143 . When slide  103  rests on housing  101 , tab  141  rests in a notch  145  in housing  101 . With slide  103  in the mating position, a block  147  on tab  141  rests against a leading edge  149  of housing  101 . As slide  103  moves from its mating position to its extraction position, notch  145 , in a fashion similar to wall  169 , keeps slide  103  in proper alignment with housing  101 . 
     Tab  141  includes a slot  151 . Slot  151  can receive an implement, such as the blade of a screwdriver, used to move slide  103  from its mating position to its extraction position. When desired, the user inserts the implement into slot  151  and urges slide  103  in the direction of the arrow in FIGS. 2 and 3. 
     As slide  103  continues to move along housing  101  in the direction of the arrows in FIGS. 2 and 3, leading edge  143  abuts a catch  153 . Catch  153  prevents further movement of slide  103  over housing  101 . In this condition, slide  103  is in the extraction position. 
     FIGS. 2 and 7; and  3  and  7   a , respectively, demonstrate two alternative methods of securing housing  101  to substrate S. In both instances, terminals  111 ,  111 ′ secure housing  101  to substrate S and are press-fit type terminals having cantilevered arms  135  that flex upon insertion of pins P. The compliant nature of arms  135  ensures a suitable electrical connection between pins P and terminals  111 . In addition, both terminals  111 ,  111 ′ have barbs  173 ,  173 ′ that pierce the wall forming the apertures in the housing for retaining terminals  111 ,  111 ′ within the housing. Barbs  173 ,  173 ′ pierce the wall upon insertion of terminals  111 ,  111 ′ into the housing, 
     The present invention uses terminals  111  shown in FIGS. 2 and 7 when surface mounting housing  101  to substrate S. Terminals  111  have a distal end  137  that receives a fusible element  139 , such as a solder ball. Fusible element  139  secures to distal ends  137  of terminals  111  using reflow techniques, preferably ball grid array (BGA) technology. International Publication number WO 98/15989 (International Application number PCT/US97/18066), herein incorporated by reference describes methods of securing a fusible element to a contact, and a contact to a substrate. 
     The present invention uses terminals  111 ′ shown in FIGS. 3 and 7 a  when mounting housing  101  to plated through holes (not shown) in substrate S. Distal ends  137 ′ of terminals  111 ′ are elongated compared to the other embodiments so that terminals  111 ′ can enter the through holes. With extended distal ends  137 ′ within the through holes, terminals  111 ′ are soldered to substrate S using known techniques. 
     FIG. 7 b  displays another alternative embodiment of the terminal. As with the other embodiments, terminal  111 ″ uses compliant arms  135 ″ for engaging pins P. In a manner different than the other embodiments, terminal  111 ″ is a floating pin design. 
     Terminal  111 ′ has an upper collar  179 ″ and a lower collar  181 ″ that, when fully inserted into the aperture in the housing, flank the housing. In other words, the medial portion of terminal  111 ″ extending between collars  179 ″,  181 ″ resides within the aperture in the housing. The remainder of terminal  111 ″ resides outside of the aperture. 
     The length of the medial portion extending between collars  179 ″,  181 ″ is greater than the thickness of the housing. The amount of difference determines the degree of movement of terminal  111 ″ in the Z-axis (i.e. normal to the plane of the housing) when inserted into the aperture. Z-axis movement of terminal  111 ″ helps offset coplanarity differences between the top of the substrate and the bottom of the housing. 
     The diameter of the medial portion of terminal  111 ″ extending between collars  179 ″,  181 ″ is less than the diameter of the aperture in the housing in order to allow unrestricted float in the Z-axis and also to allow movement of terminal  111 ″ in the X and Y-axes (i.e. parallel to the plane of the housing). Allowing movement of terminal  111 ″ in the X and Y-axes helps reduce the effects of any difference between the coefficient of thermal expansion (CTE) of the housing and of the substrate. 
     FIGS. 8-12 display a second alternative embodiment of the present invention. Features similar to the other alternative embodiments use the same reference character, save a change in the hundreds digit. A socket connector assembly  200  couples electrical component E to substrate S. Assembly  200  includes an integratable socket housing  201  and a slide  203 . 
     Socket housing  201  can be generally planar and made from a suitable insulative material. Socket housing  201  has a mounting end  205  that faces substrate S and a mating end  207  that faces electrical component E. 
     Apertures  209  extend between mounting end  205  and mating end  207  of housing  201 . Apertures  209  receive pins P of electrical component E. Conductive terminals  111  interference fit within apertures  109  to electrically connect component E to substrate S. 
     The present invention interposes a slide  203  between housing  201  and electrical component E. Slide  203  helps extract component E from housing  201 . Corresponding structure on both housing  201  and slide  203  interact to extract electrical component E from housing  201 . 
     Slide  203  can be generally planar and made from any suitable insulative material. Slide  203  has a mating end  213  that faces electrical component E and a mounting end  215  that faces housing  201 . Electrical component E rest on mating end  213 . Mounting end  215  rests on housing  201 . 
     Slide  203  moves on housing  201  between a mating position and an extraction position along the arrow shown in FIGS.  9 . In the mating position, slide  203  rests on housing  201  so that pins P of electrical component E may mate with terminals  211  of housing  201 . In the extraction position, slide  203  rests on housing  201  in such a position that pins P of electrical component E cannot mate with terminals  211  of housing  201 . Therefore, manipulation of slide  203  across housing  201  from the mating position to the extraction position disengages pins P from terminals  211 . 
     The corresponding structure on housing  201  and slide  203  helps extract electrical component E from socket connector assembly  200 . The corresponding structure on housing  201  and slide  203  interact to transform some of the movement of slide  203  across housing  201  in the direction of the arrow in FIG. 9 (from the mating position to the extraction position) into a displacement of slide  203  away from substrate S along the insertion axis. Since electrical component E rests on slide  203 , the displacement of slide  203  also urges electrical component E away from substrate S along the insertion axis in order to extract pins P from terminals  211 . The corresponding structure will now be described in detail. 
     Housing  201  and slide  203  can have interfitting notches  217  and projections  219 . The location of projections  219  within notches  217  determines the mated height of socket connector assembly  200 . When projections  219  fully nest within notches  217 , slide  203  is in the mating position. The mating position of slide  203  allows pins P to mate with terminals  211 . Socket connector assembly  200  exhibits its lowest mated height in the mating position in order to allow the interaction of pins P and terminals  211 . 
     As slide  203  moves across housing  201  along the arrow shown in FIG. 9 from the mating position towards the extraction position, projections  219  withdraw from the fully nested position. As projections  219  withdraw, the mated height of socket connector assembly  200  increases. The mated height eventually increases enough to prevent pins P from mating with terminals  211 . In other words, as slide  203  moves across housing  201  along the direction of the arrow shown in FIG. 9, slide  203  extracts pins P from terminals  211  of housing  201 , eventually removing pins P from contact with terminals  211 . At the extraction position, pins P cannot mate with terminals  211 . 
     Notches  217  and projections  219  can have a triangular cross-section, although other shapes could be used. With triangular cross-sections, a major surface  227  of projection  219  slides along a major surface  229  of notch  217 . Slide  203  moves from its mating position to its extraction position along the direction of the arrow in FIG.  9 . In the mating position, a minor surface  231  of projection  219  abuts a minor surface  233  of notch  217 . 
     The inclination of major surfaces  227 ,  229  causes the increase in mated height of socket connector assembly  200  as slide  203  moves from its mating position to its extraction position. As stated above, socket connector assembly  200  displays its smallest mated height when projections  219  fully nest within notches  217 . The mated height of socket connector assembly  200  increases as projections  219  travel along inclined major surfaces  229  of notches  217 . 
     In this alternative embodiment of the present invention, socket connector assembly  200  accommodates an electrical connector with pins residing on the entire lower surface of electrical connector E. FIG. 10 displays housing  201  capable of receiving such pins P on electrical component E. Apertures  209  occupy the center of housing  201 , while notches  217  extend around the periphery of mating end  207  of housing  201 . 
     Slide  203  rests on housing  201  and resides between electrical component E and housing  201 . As seen in FIG. 8, slide  203  can have the same peripheral extent as housing  201 . Slide  203  includes a central opening  255  that allows electrical component E to interact with apertures  209  on housing  201 . Walls  275  define opening  255 . Upon insertion of pins P into terminals  211 , electrical component E rests on mating end  213  of slide  203 . 
     Notches  217  and projections  219  preferably extend in a direction across the width of housing  201  and slide  203 , respectively. Stated differently, notches  217  and projections  219  extend in a direction that is perpendicular to the movement direction of slide  203  (shown as the arrow in FIG.  9 ). 
     Due to central opening  255 , several projections  219  cannot extend across the entire width of slide  203 . In other words, several projections  219  are discontinuous across the width of slide  203 . 
     Walls  275  of slide  203  and walls  277  of housing  201  defining the interface between the central portion and the periphery of housing  201  control the movement of slide  203  on housing  201  between its mating position and its extraction position. As slide  203  travels along housing  201  in the direction of the arrow in FIG. 9, walls  275 ,  277  abut for precise alignment. 
     In order to move slide  203  across housing  201 , slide  203  has a slot  251  that can receive an implement. When desired, the user inserts the implement into slot  251  and urges slide  203  in the direction of the arrow in FIG.  9 . 
     In the alternative arrangement shown in FIG. 12, slot  251  receives an eccentric cam  261  rotatably mounted on mounting end  207  of housing  201  by a pin  263 . In one embodiment, cam  261  includes a slot  265  to receive an implement, such as the blade of a screwdriver, used to rotate cam  261 . The user inserts the implement and rotates cam  261 . 
     In the mating position of slide  203  shown in FIG. 12, cam  261  does not engage opening  251  of slide  203 . To move slide  211  from its mating position to its the extraction position, the user rotates cam  261 . Upon rotation of cam  261  from the position shown in FIG. 12, cam  261  eventually engages a leading edge  267  of slot  251 . Further rotation of cam  261  urges slide  203  to its extraction position. 
     In an alternative embodiment (not shown), cam  261  could have a handle (not shown) that allows the user to grasp cam  261  and to manually rotate cam  261 . This alternative embodiment does not require the use of the implement described above. 
     While the present invention has been described in connection with the preferred embodiments of the various figures, it is to be understood that other similar embodiments may be used or modifications and additions may be made to the described embodiment for performing the same function of the present invention without deviating therefrom. Therefore, the present invention should not be limited to any single embodiment, but rather construed in breadth and scope in accordance with the recitation of the appended claims.

Technology Category: h