Patent Publication Number: US-7896678-B2

Title: Contact terminal having receiving arms arranged to provide robust receiving space therebetween

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention generally relates to an electrical contact terminal, and more particularly to an electrical contact terminal used in a socket connector for electrically connecting a chip module, such as a Central Processing Unit (CPU), with a printed circuit board (PCB). 
     2. Description of Related Art 
     Taiwanese Utility Pat No. 330663 issued to Zeng on Apr. 11, 2008 discloses an electrical terminal. The electrical terminal comprises a base, a solder portion extending downwardly and forwardly from the base, a connecting portion laterally bent from one side of the base, a first spring arm and a second spring arm. The first spring arm extends upwardly from the upper side of the connecting portion, and the second spring arm extends downwardly from the lower side of the connecting portion and then bent inversely and then extends upwardly. A pair of contact portions are respectively formed at distal ends of the spring portions and a pair of palms extend forwardly and outwardly from the contact portions. The pair of palms define a receiving space therebetween for guiding the insertion of the pin legs of the CPU. The first and the second spring arms define a U-shaped resilient arm on front of the base. 
     However, the U-shaped resilient arm is located on front of the base which will occupy a part of space of the receiving space such that the pin leg of the CPU will be difficult to insert into the receiving space. 
     Therefore, it is desired to provide an improved electrical terminal to solve the problems mentioned above. 
     BRIEF SUMMARY OF THE INVENTION 
     Accordingly, an object of the present invention is to provide an electrical contact terminal defining a larger space for the pin of the CPU to insert easily. 
     In order to achieve the object set forth, an electrical contact terminal made in accordance with the present invention includes a base portion having a main surface with side edges. The base portion includes an enlarged retaining portion with a mounting extending downward therefrom. An U-shaped contact engaging arms extends from a side edge of the base portion and defines a receiving space therebetween for receiving a pin leg of a CPU therebetween. 
     Other objects, advantages and novel features of the 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 
         FIG. 1  is a perspective view of an electrical contact terminal; 
         FIG. 2  is a perspective view of the electrical contact terminal assembled in an insulating housing; and 
         FIG. 3  is another perspective view of  FIG. 2  with one side wall of the insulating housing cut along line  3 - 3 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Reference will now be made to the figures to describe the present invention in detail. 
     Referring to  FIG. 1 , an electrical contact terminal  2  comprises a planar vertical base portion  20  defining a front main face and a pair of lateral side edges, a solder portion  21  extending from a bottom end of the base portion  20  and a U-shaped resilient arm  29  integrally connected to one side of the base portion  20 . The base portion  20  forms a plurality of fastening members  27  for retaining the electrical terminal  2 . The front main face extends along an X direction, while the bottom of the U-shaped arm  29  defines a plane extends along the Y direction which is perpendicular to the X direction. A connecting arm  22  extends from one lateral side edge of the planar base portion  20  along the X direction and connects the planar base portion  20  with the U-shaped arm  29 . 
     The U-shaped resilient arm  29  comprises a first flexible arm  23  extending upwardly from the upper side of the connecting arm  22  and a second flexible arm  24  extending downwardly from the lower side of the connecting arm  22 , and then, bending reversely to extend upwardly. A pair of contact portions  25  is defined on two ends of the first and the second flexible arms  23 , 24  respectively. A pair of guide portions  26  extends outwardly toward the base portion  20  from the pair of contact portions  25 . The pair of guide portions  26  defines a trumpet-shaped structure to guide a pin leg (not shown) of a CPU (not shown) to electrically connect with the contact portions  25 . A larger space  3  is defined in the front of the base portion  20  for communicating with the trumpet-shaped structure of the guide portions  26 . The U-shaped resilient arm  29  is integrated with one lateral side edge of the base portion  20  to provide enough space to define the larger space  3  in front of the base portion  20 . The contact portions  25  define therebetween a slot (not labeled) for receiving the complementary pin leg. The slot extends along X direction and parallel to the front main face. 
     Referring to  FIGS. 2-3 , an insulating housing  1  for receiving the terminals  2  comprises a passageway having two opposite first and second side walls  10 , 11 . The second side wall  11  forms several fastening portions  12 . The fastening members  27  of the base portion  20  interengage with the fastening portions  12  of the insulating housing  1  to retain the electrical contact terminal  2  in the insulating housing  1 . 
     Referring to  FIGS. 2-3 , the electrical contact terminal  2  is securely retained in the insulating housing  1 . In use, the pin leg of the CPU is inserted to the space  3  without any resistance; then, the pin is moved alone the guide portions  26  towards the pair of contact portions  25 ; finally, the pin leg of the CPU is tightly gripped by the contact portions  25  to ensure a good electrical performance interconnection therebetween. Because of the space  3  is large enough, the pin leg of the CPU can be inserted into the space  3  easily in assembly. 
     It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.