Patent Publication Number: US-2005130508-A1

Title: Structure of connector

Description:
FIELD OF THE INVENTION  
      The present invention generally relates to a structure of connector, and in particular to a socket connector that features low insertion force and firm engagement with a mating plug connector with low electrical impedance, low noise and reduced heat generated.  
     BACKGROUND OF THE INVENTION  
      Electrical connectors are known, such as U.S. Pat. No. 5,314,360 which claims a terminal block comprising: at least one clamp body having a front end and a rear face; a conductor receiving passage extending within said clamp body between said front end and said rear face, a bore within said clamp body, said bore receiving a binding post; a terminal housing with at least one mounting unit, said unit having a front opening and a bushing aperture, an interior part extending within said terminal housing from said front opening to said bushing aperture; a conductor protection element including at least a free leg, a plurality of contact blades, and said conductor protection element and said plurality of the contact blades being formed as one coherent unit; whereby said clamp body is insertable into said interior part of the housing through said front opening, in an assembled condition of said terminal block at least said free leg of said conductor protection element being situated within said conductor receiving passage and said plurality of contact blades is situated within said bushing aperture adjacent to said rear face of said clamp body.  
      The contact blades of the protection element are bent toward the same direction and forming a triangle. An opening is formed at an apex of the triangle. By means of the opening, a clamping force is provided when a pin of a plug connector (not shown) is inserted into the terminal block. Although engagement can be effectively formed between the inserted pin and the conductor protection element of the terminal block, since the protection element has a triangular configuration with an opening and since the pin has a post-like configuration, when the pin is inserted into the conductor protection element, the conductor protection element hardly completely surrounds the pin, forming a gap therebetween and thus reducing the area of contact between the pin and the conductor protection element, which results in unstable engagement, high electrical impedance, high noise and increased heat generated thereby.  
      Another known structure of socket connector is shown in  FIG. 6  of the attached drawings, comprising a block  5  having a side face in which at least one receptacle  51  is formed and an opposite side face and a bottom face in both of which holes (not shown) in communication with the receptacle  51  are formed. A terminal  6  is received and fixed in the receptacle  51 . The terminal  6  comprises an engagement section  61  and a retention section  62 . The engagement section  61  has a substantially U-shaped cross section having a central face and two side faces with a rectangular opening  611  defined in the central face. The engagement section  61  is so formed as to receive insertion of a pin of a plug connector (not shown) to form engagement therebetween.  
      Although engagement can be formed between the pin of the plug connector and the engagement section  61  of the terminal  6  of the socket connector, since the engagement section  61  has a U-shaped cross section and since the pin has a post-like configuration, when the pin is inserted from an end of the engagement section  61  into the engagement section  61 , the engagement section  61  cannot completely surround the pin with a bottom side that is the opening of the U shape forming no engagement with the pin, resulting in small contact area between the pin and the terminal  6 .  
      In addition, when the pin is inserted in a direction through the rectangular opening  611  of the engagement section  61 , similarly small contact area is resulted. Both causes unstable engagement between the pin and the terminal, which in turn results in high impedance and high noise and increased heat generated between the pin and the terminal.  
      Thus, it is desired to have a structure of connector that overcomes, or at least alleviates, the drawbacks of the conventional connectors.  
     SUMMARY OF THE INVENTION  
      Thus, a primary objective of the present invention is to provide a structure of socket connector that provides a large contact area with a pin of a plug connector and has a low insertion force to realize firm engagement between the plug connector and the socket connector.  
      To achieve the above objective, in accordance with one aspect of the present invention, a connector comprises a housing having a rear face forming at least one receptacle and upper and lower faces each forming a slot, a hole being defined in each slot and extending through the upper and lower faces into the receptacle, a securing hole being defined in the upper face and in communication with the receptacle; a terminal received in each receptacle of the housing, the terminal comprising an engagement section, a retention section extending from the engagement section, an extension section extending from the retention section and opposite to the engagement section and a wire engaging section projecting from the extension section, the engagement section comprising opposite side wings and a plurality of resilient leaves extending from each side wing and spaced from each other in the direction of the side wing, the side wings being bent so that the leaves form a substantially cylindrical configuration in axial alignment with the holes defined in the slots. Thus firm engagement, low insertion force, low impedance, reduced noise and reduce heat generation can be realized between the connector and a mating connector. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The present invention will be apparent to those skilled in the art by reading the following description of a preferred embodiment thereof, with reference to the attached drawings, in which:  
       FIG. 1  is a perspective view of a connector constructed in accordance with the present invention;  
       FIG. 2  an exploded view of the connector of the present invention;  
       FIG. 3  is a development view of a terminal of the connector in accordance with the present invention;  
       FIG. 4  is a side elevational view with portion of a housing removed to show inside details, illustrating a first way of connection of a mating connector to the connector of the optic mouse of the present invention;  
       FIG. 5  is similar to  FIG. 4 , but showing a second way of connection of the mating connector to the connector of the present invention; and  
       FIG. 6  is an exploded view of a conventional connector. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
      With reference to the drawings and in particular to  FIGS. 1-3 , a socket connector constructed in accordance with the present invention comprises a housing  1 , made of insulation material, and at least one terminal  2 , for mating a plug connector  4  (see  FIGS. 4 and 5 ) with a low insertion force and firm engagement to thereby reduce impedance and noise and heat generated between the socket connector and the plug connector.  
      The housing  1  has a rear face (not labeled) in which at least one receptacle  11  is formed for receiving the terminal  2  therein. In the embodiment illustrated, two receptacles  11  are formed in the rear face of housing  1  and two terminals  2  are received in the receptacles  11 . The housing  1  also has upper and lower faces (not labeled) in which slots  12 ,  12 A, which are opposite to each other, are respectively formed and extending between opposite side faces of the housing  1 . Through holes  13 ,  13 A are respectively formed in the slots  12 ,  12 A and extending through the upper and lower faces of the housing  1  and into the receptacles  11  respectively. A securing hole  14  is defined in the upper face of the housing  1  and extending into each receptacle  11 .  
      The terminal  2  comprises an engagement section  21 , a retention section  22  connected to the engagement section  21 , preferably by means of a neck (not labeled), an extension section  23  extending from the retention section  22  and opposite to the engagement  21  and a wire engaging section  24  further extending from the extension section  23 . The engagement section  21  comprises left and right wings  211 ,  212  extending in opposite directions from opposite sides of the neck, and a plurality of spring leaves  214  extending from each wing  211 ,  212  and spaced (as indicated by reference numeral  213 ) in the direction of the wings  211 ,  212 . The wings  211 ,  212  are bent to form a circle whereby the leaves  214  form a cylinder and spaced in a circumferential direction of the cylinder. The engagement section  21  so formed as a cylinder is positioned in the receptacle  11  and in axial alignment with the holes  13 ,  13 A defined in the upper and lower faces of the housing  1 .  
      The leaves  214  of the engagement section  21  converges to each other in the direction toward free ends of the leaves  214  whereby the cylinder of the engagement section  21  has a gradually reduced inside diameter. Further, the free end of each leaf  214  is bent outward to form a lead-in section  215 . Similar lead-in sections  215 A are formed on the wings  211 ,  212  substantially opposite to the lead-in sections  215  of the leaves  214 .  
      The retention section  22  is bent to be substantially perpendicular to the axial direction of the engagement section  21 , while the extension section  23  and the wire engaging section  24  are further bent so that the wire engaging section  24  is substantially parallel to the retention section  22 . A constraint zone  25  is thus formed between the retention section  22 , the extension section  23  and the wire engaging section  24 , which receives a securing block  3  therein.  
      A hole  221  is defined in the retention section  22  and substantially aligns with the securing hole  14  of the housing  1 .  
      The block  3  has a rear face, an upper face and a side face in which holes  31 ,  32 ,  33  are respectively formed and in communication with each other. The rear hole  31  receives the wire engaging section  24  of the terminal  2  therein. A fastener  15 , such a bolt, extends through the securing hole  14  of the housing and the hole  221  of the terminal  2  to engage the hole  32  of the block  3 . Preferably, the hole  32  is internally threaded for threadingly engaging the bolt  15  thereby securing the block  3  and the terminal  2  in the receptacle  11  of the housing  1 .  
      Also referring to  FIGS. 4 and 5 , a conductor, such as a wire (not shown), is inserted into the hole  31  of the block  3 . The fastener  5  is sized to have a tip end thereof engage and depress the wire engaging section  24  of the terminal  2  against the wire thereby forming secure electrical engagement therebetween. This can be simply done by tightening the bolt  15  in the internally threaded hole  32  of the block  3 .  
      To mate the plug connector  4  with the socket connector of the present invention, a pin  41  of the plug connector  4  can be fit into either hole  13 ,  13 A formed in the upper or lower faces of the housing  1 . If the pin  41  is fit into the hole  13  of the upper face of the housing  1 , the pin  41  is guided by the lead-in sections  215 A of the terminal  2  into the cylinder formed by the leaves  214  thereby electrically engaging the leaves  214 , especially due to the reduced diameter of the cylinder of the engagement section  21 . On the other hand, when the pin  41  is fit into the hole  13 A of the lower face of the housing  1 , the pin  41  is guided by the lead-in sections  215  of the leaves  214  into engagement with the leaves  214 . Due to the lead-in sections  215 ,  215 A and the resiliency of the leaves  214 , a low insertion force is required in mating the pin  41  with the engagement section  21 . Further, since the leaves  214  of the engagement section  21  is arranged to form a cylinder, a substantially complete surrounding of the pin  41  by the leaves  214  is realized in the present invention and the maximum contact area is formed between the pin  41  and the engagement section  21 . As a result, impedance between the pin  41  and the engagement section  21  is reduced, noise caused thereby is also reduced and heat generated between the pin  41  and the engagement section  21  is also reduced due to the reduced impedance therebetween.  
      Although the present invention has been described with reference to the preferred embodiment thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims.