Abstract:
The present invention discloses a coupling terminal structure and electrical connector using the same. The coupling terminal structure comprises: at least a pair of first terminal and second terminal, wherein the first terminal includes a first contact portion, a first neck portion and a first extension portion, the second terminal includes a second contact portion, a second neck portion and a second extension portion. The first contact portion is disposed aside to the second contact portion at a first distance, while the first extension portion is disposed aside to the second extension portion at a second distance. The first distance is greater than the second distance, thereby forming an electromagnetic coupling effect between the first extension portion and the second extension portion to provide better shielding and decrease interference between and within terminals.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a coupling terminal structure and an electrical connector using the same; in particular, to a coupling terminal structure and an electrical connector which can provide electromagnetic coupling effect by structural properties of the terminals to reduce crosstalk interference. 
         [0003]    2. Description of Related Art 
         [0004]      FIG. 1  shows a conventional coupling terminal of an electrical connector. The first terminal  1  and the second terminal  2  have overall similar form and structure, and are generally parallel from end to end. For example, assume that a cutting line cuts the first terminal  1  and the second terminal  2 , which are arranged side by side, near their left ends at two first cutting points ( 11 ,  21 ). P is defined as the distance between the two first cutting points ( 11 ,  21 ). Similarly, assume that a cutting line cuts the first terminal  1  and the second terminal  2  near their midsections of the two terminals at two second cutting points ( 12 ,  22 ). The distance between the two second cutting points ( 12 ,  22 ) is essentially equal to P. Described above is the conventional practice and structural arrangement of conventional coupling terminals. 
         [0005]    However, crosstalk is a persisting problem between neighboring terminals or within a terminal itself, especially when the electrical connector is used for transmitting data at high speed (e.g. 3 Gbps). In order to transmit a large amount of information in a short amount of time, the signals need to be transmitted at high bandwidths. Therefore, the frequency of the signals needs to be higher, possibly between 3 Ghz and 5 Ghz or higher. Higher signal frequencies increase crosstalk, which affect the integrity of data transmission and raise chances for bit error. 
         [0006]    Therefore if proper shielding cannot be provided to reduce crosstalk, signal frequency must be reduced which leads to bottlenecking of data transmission and reduction of data transmission frequency. Even if proper shielding can be provided between neighboring terminals, an increase in shielding units and grounding units increases the volume and weight of electrical connectors, which contradicts the current trend of miniaturization of electronic elements and unnecessarily increases production cost. 
         [0007]    Hence, the present inventor believes the above mentioned disadvantages can be overcome, and through devoted research combined with application of theory, finally proposes the present disclosure which has a reasonable design and effectively improves upon the above mentioned disadvantages. 
       SUMMARY OF THE INVENTION 
       [0008]    The object of the present disclosure is to provide a coupling terminal structure of an electrical connector for improving the problem of crosstalk between terminals, in order to increase the quality of data transmission. 
         [0009]    In order to achieve the aforementioned objects, the present disclosure provides a coupling terminal structure of an electrical connector, which mutually creates electromagnetic coupling effect when transmitting data signals so as to reduce crosstalk through non-grounding shielding structures. The coupling terminal structure includes: a plurality of first terminals and second terminals in pairs, mutually arranged side by side and grouped to form a three-dimensional terminal network. The first terminal includes a first contact portion, a first neck portion and a first extension portion. The second terminal includes a second contact portion corresponding to the first contact portion, a second neck portion corresponding to the first neck portion and a second extension portion corresponding to the first extension portion. The first contact portion and the second contact portion are arranged with a first distance therebetween. The first extension portion and the second extension portion are arranged with a second distance therebetween. The first distance is larger than the second distance. A wide surface of the first extension portion orients toward a wide surface of the second extension portion. By this configuration, electromagnetic coupling effect is created between the first extension portion and the second extension portion. 
         [0010]    In order to achieve the aforementioned objects, the present disclosure provides an electrical connector including the mentioned coupling terminal structure. The electrical connector includes a dielectric housing with the terminal network disposed therein. The dielectric housing fixes the first terminals and the second terminals of the terminal network in place, and consequently fixes the first distance and the second distance. The first contact portion and the second contact portion form an electrical-connection interface on any face of the electrical connector. 
         [0011]    In summary, in regards to the principle technical features of the present disclosure, the first distance between the first contact portion and the second contact portion is larger than the second distance between the extension portion and the second extension portion, and the first wide face orients toward the second wide face. In other words, the preferable electromagnetic coupling effect is generated due to the mutually facing wide faces, which are formed in relative proximity, of the first extension portion and second extension portion. As a result, the transmitted signal is better coated, interference to and from foreign objects is reduced, and signal transmission quality of the electrical connector is effectively increased. 
         [0012]    In order to further the understanding regarding the present invention, the following embodiments are provided along with illustrations to facilitate the disclosure of the present invention without limiting the same. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  shows a schematic diagram of a conventional connector terminal; 
           [0014]      FIG. 2  shows a perspective diagram of a coupling terminal structure of an electrical connector of the present disclosure; 
           [0015]      FIG. 3  shows a top view of a first terminal and a second terminal of a coupling terminal of an electrical connector of the present disclosure; 
           [0016]      FIG. 4  shows a side view of a coupling terminal of an electrical connector of the present disclosure; 
           [0017]      FIG. 5  shows a graph of crosstalk under varying frequencies of a coupling terminal of an electrical connector of the present disclosure and a conventional terminal; 
           [0018]      FIG. 6  shows a schematic diagram of an electrical connector of the present disclosure; 
           [0019]      FIG. 7  shows a top view of an electrical connector and part of the terminals within of the present disclosure; and 
           [0020]      FIG. 8  shows a perspective schematic diagram of an electrical connector and a partial internal view of the terminals of the present disclosure. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0021]    The aforementioned illustrations and following detailed descriptions are exemplary for the purpose of further explaining the scope of the present invention. Other objectives and advantages related to the present invention will be illustrated in the subsequent descriptions and appended drawings. 
         [0022]    Referring to  FIG. 2 ,  FIG. 3 , and  FIG. 4 , in order to improve the problem of crosstalk between terminals or within a terminal, the present disclosure provides a coupling terminal structure of an electrical connector which mutually creates electromagnetic coupling effect when transmitting data signals so as to reduce crosstalk through non-grounding shielding structures. For example, the two top-most terminals include a plurality of the first terminals  10  and the second terminals  20  in pairs, mutually arranged side by side and grouped to form a three-dimensional terminal network CL.  FIG. 2  shows a 2×5 terminal network CL, but the present disclosure is not limited thereto. The terminal network CL can also be 2×5, 6×5, 4×8, etc. the first terminal  10  and the second terminal  20  can be electrical terminals of any type, such as: single-ended signal terminals, differential signal terminals, or ground terminals. A pair of differential signal terminals is an ideal example for further explanation. The first terminal  10  and the second terminal  20  can be respectively a positive differential signal terminal and a negative differential signal terminal. 
         [0023]    Structurally, the first terminal sequentially includes a first contact portion  11 , a first neck portion  12  and a first extension portion  13 . The second terminal  20  sequentially includes a second contact portion  21  corresponding to the first contact portion  11 , a second neck portion  22  corresponding to the first neck portion  12 , and a second extension portion  23  corresponding to the first extension portion  13 . A first distance D1 is the distance between the contact portion  11  and the second contact portion  21 . A second distance D2 is the distance between the first extension portion  13  and the second extension portion  23 . The first distance D1 is larger than the second distance D2. The first extension portion  13  and the second extension portion  23  are respectively a strip shaped conducting body with a wide surface ( FIG. 2 , label omitted) and a narrow surface ( FIG. 2 , label omitted). Ideally the wide surface of the first extension portion  13  orients toward the wide surface of the second extension portion  23 , for enhancing the electromagnetic coupling effect. 
         [0024]    Therefore, in order to improve crosstalk between terminals, the structure of the terminals of the present disclosure require that the first distance D1 between the first contact portion  11  and the second contact portion  12  be larger than the second distance D2 between the first extension portion  13  and the second extension portion  23 . Taking the first terminal  10  for example, as long as the above feature is complied, then the first neck portion  12  connecting the first contact portion  11  and the first extension portion  13  does not need to connect the first contact portion  11  and the first extension portion  13  by any definite method or structure. Likewise, the same applies to the second neck portion  22 . 
         [0025]    As shown in top view of  FIG. 3 , the first terminal  10  and the second terminal  20  exhibit reflective symmetry about plane AX. Analogously, other terminals beside the first terminal  10  and the second terminal  20  in  FIG. 2  or  FIG. 4  likewise exhibit reflective symmetry. However, the present disclosure is not limited to such structure with reflective symmetry. As shown in  FIG. 3 , starting from the first contact portion  11 , the first neck portion  12  bends inwardly toward the plane of symmetry AX and connects to the first extension portion  13 . The second neck portion  22  corresponding to the first neck portion  12  also bends inwardly toward the plane of symmetry AX, and then extends to the second extension portion  23 . Therefore, in order for the first distance D1 to be larger than the second distance D2, during manufacturing of terminals, a midsection of a terminal is press worked to respectively form a first neck portion  12  and a second neck portion  22  by bending one terminal towards the other terminal or bending the two terminals toward the plane of symmetry AX, such that the second distance D2 between the first extension portion  13  and the second extension portion  23  respectively behind the first neck portion  12  and the second neck portion  22  is consequently smaller than the first distance D1. 
         [0026]    Ideally, the ratio of the first distance D1 to second distance D2 ratio is between 40:7 (ratio of 5.714) and 40:15 (ratio of 2.667). In a more precise embodiment, the first distance D1 can be 2 millimeters, and the second distance D2 can be 0.55 millimeters. 
         [0027]    Additionally, in order to be compatible with structural specifications of dielectric housings of conventional electrical connectors, the first contact portion  11  can be parallel with or symmetrical to the second contact portion  21 . Referring to  FIG. 4 , the first contact portion can further include a first gripping portion  111 . The first gripping portion  111  further includes a top gripping arm  1111  and a bottom gripping arm  1112  each having an arc shape such that the distance between them is smaller than the distance between them when an arc shape is absent. A minimum distance is formed between the top and bottom gripping arms  1111  and  1112  to provide a better gripping effect. Due to the arc shape, the tips of the top and bottom gripping arms  1111  and  1112  respectively form a top curled tip  1113  and a bottom curled tip  1114 . As a result, a relatively widest opening is formed between the top gripping arm  1111  and the bottom gripping arm  1112  from the top curled tip  1113  to the bottom curled tip  1114 . When mating with a male plug, the wide-to-narrow structure can provide a mating guide, facilitating the plugging of a male plug (not shown in the figure). Similarly, the second terminal  20  has a second gripping portion similar in structure to the first gripping portion  111  (refer to  FIG. 2 , label omitted). 
         [0028]    As shown in  FIG. 2 ,  FIG. 3  and  FIG. 4 , taking the first terminal  10  for example, the first neck portion  12  includes a first twist portion  121  proximal to the first contact portion  11 . The wide surface W of the first extension portion  13  faces sideways, and the narrow surface (not labeled) faces downwards ( FIG. 4 ). However, in order for the first contact portion  11  to form the abovementioned structure favorable for mating with male plugs, the first twist portion  121  is used so that the first contact portion  11  can rotate about its longitudinal direction such that the narrow surface (N) can face sideways and the wide surface (not labeled) can face upward or downward. 
         [0029]    Ideally, the first terminal  10  extends from the first extension portion  13  to form a third neck portion  14  and a third contact portion  15 . In other words, the first contact portion  11  and the third contact portion  15  are respectively positioned at two ends of the first terminal. 
         [0030]    Similarly, the second terminal  20  extends from the second extension portion  23  to form a fourth neck portion  24  corresponding to the third neck portion  14  and a fourth contact portion  25  corresponding to the third contact portion  15 . In the present embodiment the third contact portion  15  and the fourth contact portion  25  are both pins with tear-drop shaped apertures, but the present disclosure is not limited to the same. The third contact portion  15  and the fourth contact portion  25  are respectively the other end portions of the first terminal  10  and the second terminal  20  in the present disclosure, and can be electrical contacts, pins, male or female plugs of any specification or form. However, most importantly, a third distance D3 between the third contact portion  15  and the fourth contact portion  25  is necessarily larger than the second distance D2. The relative size of the third distance D3 to the first distance D1 is not limited, but is preferably equal to the first distance D1. The individual and relative structures of the third neck portion  14  and the fourth neck portion  24  are similar to that of the first neck portion  12  and the second neck portion  22 , and are not further detailed herein. 
         [0031]    Ideally, the present disclosure is embodied by a right angle adapter of an electrical connector. The first extension portion  13  can further have a first curved portion  131 , the first curved portion  131  is usually a curve having a substantially right angle. As shown in  FIG. 4 , the curve bends downward, but is not limited to such configuration, and can also bend upward out of or into the page of  FIG. 4 . The angle of the curve is likewise not limited herein. Referring back to  FIG. 4 , the first curved portion  131  can guide the orientation of the third contact portion  15  for guiding the orientations of the third contact portion  15  and the first contact portion  11  to be perpendicular. The second extension portion further has a second curved portion  231  corresponding to the first curved portion  131 . The second curved portion  231  guides the fourth contact portion  25  to be perpendicular to the second contact portion  21 . However, regardless of how the first curved portion  131  and the second curved portion  231  are bended, resulting the third distance D3 must be smaller than the second distance D2 in order to comply with the conditions above. 
         [0032]    As a side note, the first distance D1, the second distance D2 and the third distance D3 are defined as: taking the first distance D1 for example, the distance is defined as the distance between the central axes (as shown in  FIG. 3 , label omitted) of the first contact portion  11  and the second contact portion  21 . The second distance D2 and the third distance D3 are similarly defined. 
         [0033]    However, the first curved portion  131  may be unnecessary when not used on right angle adapters. Taking for example the first terminal  10 ′ on the bottom of  FIG. 2  and  FIG. 4 , the third neck portion  14 ′ directly extends downward from the first extension portion  13 ′ such that the third contact portion  15 ′ ultimately faces downward. The first curved portion  131 ′ exists but is not very conspicuous. 
         [0034]    Referring to  FIG. 5 , the present disclosure can effectively reduce crosstalk between or within terminals by the abovementioned technical features. The vertical axis of  FIG. 5  is the noise value in decibels (dB). The horizontal axis is the signal frequency in gigahertz (GHz). The first curve L1 is the noise level of crosstalk when the coupling terminal structure of the electrical connector of the present disclosure transmits signal at various frequencies. The first curve L2 is the noise level of crosstalk when a conventional coupling terminal structure transmits signal at various frequencies. It can be seen from  FIG. 5  that transmitting signal with the present disclosure creates less crosstalk than the conventional terminal does. Therefore, the present disclosure indeed effectively reduces crosstalk and increases the signal to noise ratio. 
         [0035]    Referring to  FIG. 2  and  FIG. 6 , the present disclosure provides an electrical connector including the coupling terminal structure. The electrical connector includes a dielectric housing (label omitted) having the first terminal  10  and the second terminal  20  arranged therein. The dielectric housing fixes the first terminal  10  and the second terminal  20 , thereby fixing the first distance D1, the second distance D2 and the third distance D3. The first contact portion  11  and the second contact portion  21  can form an electrical connection interface on any face of the electrical connector. 
         [0036]    The dielectric housing can be formed integrally as one body by injection molding, but is not limited thereto. As shown in  FIG. 6 , the dielectric housing of the present embodiment comprises a first housing  30 , a second housing  40  and a third housing  50 . The third housing  50  has a plurality of openings  51 . The first contact portion  11  and the second contact portion  21  are enclosed by the third housing  50  and align with the openings  51  to form an electrical connection interface (label omitted). The electrical connection interface can be a male plug interface or a female seat interface. 
         [0037]    Ideally, the male plug can be a gold finger male plug, pins with tear drop shaped apertures, or other pins. The female seat can be a gold finger female seat, or a female seat with gripping ability. The electrical female seat formed on the side of the third housing  50  of the present embodiment is an ideal example. The demonstrations of the first contact portion  11  and the second contact portion  21  and modifications of are applicable on the third contact portion  15  and the fourth contact portion  25 . 
         [0038]    As shown in  FIG. 7  and  FIG. 8 , the third housing  50  is removed from the electrical connector, the first housing  30  and the second housing  40  enclose most of the first extension portion  13  and the second extension portion  23 , for fixing the first terminal  10  and the second terminal  20 , thereby fixing the second distance D2 between the first extension portion  13  and the second extension portion  23 . The first housing  30  and the second housing  40  respectively extend to form a first sub housing  31  and a second sub housing  41  proximate to the first neck portion  12  and the second neck portion  22 . The first sub housing  31  and the second sub housing  41  are formed slightly longer in the vertical direction than the first housing  30  and the second housing  40 , respectively, in order to accommodate and enclose more first terminal  10 ′ below. Moreover, in regards to the third contact portion  15  and the fourth contact portion  25 , the first housing  30  and the second housing  40  can also provide fixing functionality for the third distance D3. 
         [0039]    In summary, the present disclosure can effectively improve crosstalk between or within terminals, optimizing signal transmission quality. Moreover, through structural arrangement, the present disclosure creates natural electromagnetic coupling effect such that the transmitted signal can be preferably shielded. This method differs from the conventional shielding and grounding method and has the benefit of reducing volume, weight, and production cost. 
         [0040]    The descriptions illustrated supra set forth simply the preferred embodiments of the present invention; however, the characteristics of the present invention are by no means restricted thereto. All changes, alternations, or modifications conveniently considered by those skilled in the art are deemed to be encompassed within the scope of the present invention delineated by the following claims.