Patent Publication Number: US-8986049-B2

Title: Electrical connector

Description:
RELATED APPLICATIONS 
     The application is a national phase of PCT Application No. PCT/US11/30330, filed Mar. 29, 2011, which in turn claims priority to Chinese Patent Application No. 201020160159.7, filed Mar. 29, 2010, both of which are incorporated herein by reference in their entirety. 
     FIELD OF THE INVENTION 
     The present application relates to an electrical connector, more specifically to a small electrical connector that can beneficially increase the stability of an electrical connection. 
     DESCRIPTION OF RELATED ART 
     With the development of electrical and information technologies, more and more standardized electrical connectors are being developed and utilized. Looking at Taiwanese patent TW94212910 as an example, it discloses a connector  7  as shown in  FIG. 1  that is suitable for use in transferring digital audio-video data. The connector  7  consists of a plastic upper lip  70 , an upper layer plastic tongue  71 , a lower layer plastic tongue  72 , a plastic lower lip  73 , a metal outer shell  74 , and metal pins  75 . Of these, the plastic upper lip  70 , upper layer plastic tongue  71 , lower layer plastic tongue  72 , and plastic lower lip  73  are stacked together from top to bottom to form a stacked body. Then it is encased by the metal outer shell  74  from the front of the stacked body, and together they form the connector  7 . As shown in  FIG. 2 , the majority of the metal pins  75  are contained within the upper layer plastic tongue  71  and lower layer plastic tongue  72 , wherein the contact portion  750  of the metal pins  75  contained within the upper layer plastic tongue  71  has a ∪ shape, and the contact portion  750  of the metal pins  75  contained within the lower layer plastic tongue  72  has a ∩ shape; the front ends  751  of the corresponding metal pins  75  are fastened inside the channels  700  of the plastic upper lip  70  and the plastic lower lip  73 , respectively, in order to prevent the terminals from sticking up inappropriately, which could result in damage during mating. 
     As can be appreciated, therefore, when the electrical connector  7  is mated to the inserted connector socket  8 , the contact portion  750  of the metal pins  75  relies only upon the elastic deformation of its own material to contact the surface of the inserted connector socket  8 . After a long period of use or multiple insertions and removals, the contact portion  750 , as it is susceptible to non-elastic deformation (e.g., the terminals taking a permanent set) due to excessive force during insertion and removal or due to elastic fatigue, it can be difficult to tightly mate the electrical connector  7  to the inserted connector socket  8 . Thus the stability of the electrical connection and the quality of signal transmission may be impacted. In addition, because the electrical connector  7  requires that sufficient deformation space (a ∪ shaped or ∩ shaped space) is left for the metal pins  75  inside the plastic stacked body, the connector  7  is quite thick, making it difficult to adapt to the trend of miniaturization in electronic products. In addition, its plastic body consists of two portions, a plastic upper lip  70  and a plastic lower lip  73 , which tend to make assembly more difficult. Consequentially, further improvements to a connector would be appreciated by certain individuals. 
     BRIEF SUMMARY 
     An electrical connector, comprising at least an insulator body, a number of terminals arranged on the insulator body, and a shell surrounding the insulator body. The insulator body comprises a main body and a mating portion extending forward from the main body, wherein the mating portion has a front end with a mating opening, and the top and bottom sides of the mating opening have a number of terminal channels. The terminal can be cantilevered so that an elastic portion extending forward from a base and an arched contact portion extends from the elastic portion and an abutting portion extends from the contact portion. In an embodiment, a single housing can be configured to receive a first and second frame that each support terminals respectively positioned on the top and bottom sides of the mating opening. Starting from the junction of the elastic portion and the contact portion, the thickness of the terminals can be configured to gradually thin toward the abutting portion. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The present invention is illustrated by way of example and not limited in the accompanying figures in which like reference numerals indicate similar elements and in which: 
         FIG. 1  is a perspective exploded view of a prior art electrical connector. 
         FIG. 2  is a sectional view of a prior electrical connector during mating. 
         FIG. 3  is a perspective view of an embodiment of an electrical connector and it also includes a cable and a protective casing. 
         FIG. 4  is a perspective exploded view of the electrical connector depicted in  FIG. 3 . 
         FIG. 5  is another perspective exploded view of the electrical connector depicted in  FIG. 3 . 
         FIG. 6  is another perspective exploded view of the electrical connector depicted in  FIG. 3 . 
         FIG. 7  is another perspective exploded view of the electrical connector depicted in  FIG. 3 . 
         FIG. 8  is a perspective view of the electrical connector depicted in  FIG. 3  without the protective casing. 
         FIG. 9  is an elevated front view of the connector depicted in  FIG. 8 . 
         FIG. 10  is an elevated side view of a section taken along line A-A in  FIG. 9 . 
         FIG. 11  is an enlarged partial view of section depicted in  FIG. 10 . 
     
    
    
     DETAILED DESCRIPTION 
     The detailed description that follows describes exemplary embodiments and is not intended to be limited to the expressly disclosed combination(s). Therefore, unless otherwise noted, features disclosed herein may be combined together to form additional combinations that were not otherwise shown for purposes of brevity. 
     As can be appreciated by the details described below, in the depicted an embodiment of the depicted electrical connector, the contact portion of the terminals can experience elastic movement within the terminal grooves, and it does not rely solely upon the elastic deformation of its own material as in prior art. Therefore, it is possible to maintain tight contact with another socket connector after a long period of use and thus avoid poor contact between mating terminals. As a result, the electrical connector has relatively higher operating stability and a fairly long life. In addition, by thinning the abutting portion of the terminals, it is possible to increase the gap between the abutting portion and the shell while ensuring that the thickness of the elastic portion gives it fairly strong elasticity, thus guarding against mistaken contact between the abutting portion and the shell during mating which would lead to signal transmission failure. 
       FIG. 3  is a perspective view of the electrical connector  1  of an embodiment. As depicted in  FIG. 3 , the electrical connector  1  is a micro high-definition multimedia interface D-type cable connector. The electrical connector  1  comprises an insulator body  2 , a number of terminals  3  supported by the insulator body  2 , and a shell  4  surrounding the insulator body  2 . The electrical connector  1  is further set up with a cable  10  that is electrically connected to the terminals  3  and a protective casing  11 . 
       FIGS. 4 ,  5 , and  6  are perspective exploded views of the embodiment of the electrical connector  1 . As shown in  FIGS. 4 ,  5 , and  6 , the insulator body  2  comprises a main body  20 , mating portion  21  protruding forward from the front face  200  of the main body  20 , and two flanges  22  protruding from the bottom and top ends of the rear face  201  of the main body  20 . The front end of the mating portion  21  has a mating aperture  23 , and the top side wall  230  and bottom side wall  231  of the mating aperture  23  have a number of parallel terminal grooves  24 . Each of the two flanges  22  has a fixing hole  220 . In addition, the main body  20  has a reinforcement portion  25  protruding forward on each of the two sides of the mating portion  21 , and the reinforcement portion  25  can boost the compressive strength of the insulator body  2 . 
     As depicted, each terminal  3  comprises a base portion  30 , an elastic portion  31  extending forward from the base portion  30 , a soldering portion  32  extending backward from the base portion  30 , an arched contact portion  33  extending forward from the elastic portion  31 , and an abutting portion  34  located at the end of the arched contact portion  33 . As is typical, the terminal is conductive and can be formed of a desired alloy such as a copper-based alloy. 
     In the present embodiment, the electrical connector  1  further comprises a top row frame  5  and a bottom row frame  6 , thus the corresponding terminal grooves  24  on the insulator body  2  separate all of the terminals  3  into top row terminals  36  and bottom row terminals  37 . The top row frame  5  and bottom row frame  6  use an insert molding system to respectively fix the corresponding top row terminals  36  and bottom row terminals  37 . The soldering portions  32  of the top row terminals  36  and bottom row terminals  37  extend backward from the back end of the top row frame  5  and the bottom row frame  6 , respectively. The elastic portion  31  of the top row terminals  36  and bottom row terminals  37  extends forward from a front end of the top row frame  5  and the bottom row frame  6 , respectively. The top row frame  5  has a number of positioning holes  50 , and the bottom row frame  6  has a number of corresponding positioning posts  60 . These positioning posts  60  can be inserted correspondingly into the positioning holes  50 , thus assembling the two frames together. In order to prevent slipping between the top row frame  5  and the bottom row frame  6 , two steps  61  protrude from the two sides of the top surface of the bottom row frame  6 , and they match up with two grooves  54  on the two sides of the bottom surface of the top row frame  5  to form an anti-slip structure. In addition, the top surface of the top row frame  5  and the bottom surface of the bottom row frame  6  each have a wedge  13  that is low in front and high in back, and each of these two wedges  13  can be fixed correspondingly inside the fixing holes  220  of the flanges  22  on the insulator body  2 . 
     Those skilled in the art would understand that the above description should not be viewed as limiting the specific positions of the top row frame  5  and bottom row frame  6  assembly structure. Thus, relevant adjustments can be made to the two as needed in actual applications. For example, if the positioning holes  50  are on the bottom row frame  6 , then the matching positioning posts  60  will be on the top row frame  5 . 
       FIG. 7  is a perspective exploded view of an embodiment of an electrical connector  1 . As shown, the shell  4 , which helps providing shielding, primarily surrounds the outside of the main body  20  and mating portion  21  of the insulator body  2 . The shell  4  has a main shell  40  and a mating shell  41  corresponding to the main body  20  and mating portion  21 , and the left and right sides of the main shell  40  each have a protruding portion  42  protruding inward. 
     During assembly, the top row frame  5  is first assembled with the bottom row frame  6 , then they are inserted forward between the two flanges  22  of the insulator body  2 . The wedges  13  of the top row frame  5  and the bottom row frame  6 , designed to be low in front and high in back, can facilitate the insertion process, and after assembly they are wedged inside the corresponding fixing holes  220  (as shown in  FIGS. 8 and 10 ), thus stopping the top row frame  5  and bottom row frame  6  inside the insulator body  2  and making it impossible for them to come back out. The assembly structure is simple and reliable. The shell  4  can be assembled onto the insulator body  2  from front to back. As shown in  FIG. 8 , the protruding portions  42  on either side can be bent further inward, wedging them onto the rear face  201  of the insulator body  2 , in order to strength the combination of the shell  4  and the insulator body  2  and making sure the two do not come apart. 
     As shown in  FIGS. 9 and 10 , the elastic portion  31 , contact portion  33 , and abutting portion  34  of each terminal  3  are contained with the corresponding terminal grooves  24  on the insulator body  2 , and the top end of the contact portion  33  protrudes into the mating space of the mating aperture  23 . As depicted, the part of the front end of each terminal groove  24  that is at the corresponding terminal&#39;s  3  abutting portion  34  runs up and down along one side of the insulator body&#39;s  2  mating portion  21 , thus making it possible to link up with the shell  4 . The front end of the mating portion  21  of the insulator body  2  has an abutting wall  26  extending between the mating aperture  23  and terminal grooves  24 . The abutting portion  34  of the terminals  3  can butt up against the lower part of the abutting wall  26 , thus stopping the front end of the terminals  3  and avoiding having the contact portion  33  and abutting portion  34  of the terminals  3  stick up too much and enter the mating aperture  23 . Furthermore, it avoids bending damage from having the front end of the terminals  3  knock against another socket connector during mating (not pictured). 
     In addition, when the electrical connector of the present embodiment is not mated to another socket connector, because the elastic portion  31  of the terminals  3  already experienced a small amount of elastic deformation when being assembled onto the insulator body  2 , the abutting portion  34  exerts preloaded elastic compression on the abutting wall  26 . Thus, when it is mated to another socket connector, the contact portion  33  only needs to move down a small distance to make it possible to achieve considerable elastic recovery force, thus lowering the contact resistance between the contact portion  33  and the terminals of the mated socket connector and helping to improve signal quality. 
     There is a space for movement that is greater than the thickness of the abutting portion  34  in the terminal grooves  24  between the abutting wall  36  of the insulator body  2  and the shell  4  below it, thus enabling the abutting portion  34  to elastically move up and down within it. However, in order to guard against the possibility of contact between the abutting portion  34  and the shell  4  during mating, and to avoid mistaken grounding (which would lead to a failure in signal transmission), it is useful to have a gap  15  between the abutting portion  34  and the shell  4  that is larger than the elastic displacement  14  of the abutting portion  34  during mating, even if a given gap  16  is maintained between the abutting portion  34  and the shell  4  when the electrical connector  1  is mated to another socket connector (the position of the terminals  3  in  FIG. 11  is shown by a dotted line). 
     Taking into consideration the further miniaturization of electrical connectors  1  and to help prevent the abutting portion  34  from contacting the shell  4 , in an embodiment a stamping process can be used to gradually thin the thickness of these terminals  3 , starting from the junction of the elastic portion  31  and the contact portion  33 , as it moves toward the abutting portion  34 . The gradual thinning of the terminal thus helps increase the width of the gap  16 . In an embodiment, for example, the thickness of the elastic portion  31  is about 0.20 mm, the thickness of the contact portion  33  is about 0.15 mm, and the thickness of the abutting portion  34  is about 0.12 mm. Thus, the thickness of the abutting portion can be reduced so that the thickness of the abutting portion is less than 70% of the elastic portion (e.g., 0.12/0.20=60%). In this way, it is possible to increase the gap  16  between the abutting portion  34  and the shell  4  during mating so as to help prevent the abutting portion  34  from inappropriately contacting the shell  4  during mating (even if the size of the connector is kept small) as grounding the terminal to the shield could lead to signal transmission failure. 
     Compared to prior electrical connectors, the front end of the terminal grooves  24  runs up and down one side of the mating portion  21 , using the thickness of the original mating portion&#39;s  21  side walls to provide space for upward and downward elastic displacement of the terminals  3  during mating, thus reducing the thickness of the mating portion  21  of the electrical connector  1 . At the same time,  FIG. 11  illustrates support from the design of the abutting wall  26  such that the front end of the terminals  3  is held in a partially flexed position so that it cannot enter too far into the mating grove  23  and cause collision damage with the other socket connector during mating. In addition, because the contact portion  33  of the terminals  3  can move up and down to a certain extent, sufficient elastic deformation support can be obtained from other portions such as the elastic portion  31  (e.g., the stress exerted on the terminal need not cause plastic deformation), and it no longer relies solely upon the elasticity of the material at the contact portion  33  itself. 
     As a result, the contact portion  33  of the terminals  3  is less susceptible to elastic fatigue (e.g., less likely to take a set), and the negative effects on the terminals  3  due to excessive force or stress being placed on the contact portion  33  during insertion and removal can be reduced. Consequentially, it is possible to avoid a poor connection when the electrical connector  1  is mated to a second socket connector after a long period of use with a first socket connector. In addition, in order to further reduce the thickness of the mating portion  21  of the electrical connector  1 , the front end of the terminals  3  can be thinned accordingly. As can be appreciated, this can help avoid inadvertent contact and grounding to the shield shell  4  during mating (as grounding of signal contacts would tend to create signal transmission failure). 
     The disclosure provided herein describes features in terms of preferred and exemplary embodiments thereof. Numerous other embodiments, modifications and variations within the scope and spirit of the appended claims will occur to persons of ordinary skill in the art from a review of this disclosure.