Patent Publication Number: US-9413123-B2

Title: Electrical plug connector

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This non-provisional application claims priority under 35 U.S.C. §119(a) on Patent Application No. 103110940 and 104108695, filed in Taiwan, R.O.C. on Mar. 24, 2014 and Mar. 18, 2015, the entire contents of which are hereby incorporated by reference. 
     FIELD OF THE INVENTION 
     The instant disclosure relates to an electrical connector, and more particularly to an electrical plug connector. 
     BACKGROUND 
     Generally, Universal Serial Bus (USB) is a serial bus standard to the PC architecture with a focus on computer interface, consumer and productivity applications. The existing Universal Serial Bus (USB) interconnects have the attributes of plug-and-play and ease of use, from the end user&#39;s point of view. Now, as technology innovation marches forward, new kinds of devices, media formats and large inexpensive storage products are converging. They require significantly more bus bandwidth to maintain the interactive experience that users have come to expect. In addition, user applications demand a higher performance between the PC and sophisticated peripherals. The transmission rate of USB 2.0 is insufficient. Consequently, faster serial bus interfaces, such as USB 3.0, have been developed to address the need by adding a higher transmission rate to match usage patterns and devices. 
     A conventional USB electrical receptacle connector includes plate transmission terminals and a USB electrical plug connector includes elastic transmission terminals. When the conventional USB electrical receptacle connector with the conventional USB electrical plug connector in an improper orientation, the elastic transmission terminals or a tongue portion of the conventional USB electrical plug connector may be damaged or even broken, resulting in the disablement of the elastic transmission terminals or the tongue portion. 
     Furthermore, the surface of an iron shell of the conventional USB electrical receptacle connector or the surface of the conventional USB electrical plug connector is provided with a crack for firmly connection. However, these cracks would adversely influence the shielding effect of the iron shell to induce interferences (such as Electromagnetic Interference (EMI), Radio-Frequency Interference (RFI), and the like), with other signals during signal transmission. Therefore, a problem of serious crosstalk between the terminals of conventional connector is to be solved. 
     SUMMARY OF THE INVENTION 
     In view of the above-mentioned problems, the instant disclosure provides an electrical plug connector. The electrical plug connector comprises a metal shell, an insulation housing, a plurality of upper-row elastic terminals, and a plurality of lower-row elastic terminals. The metal shell defines a receiving cavity therein. The insulation housing is in the receiving cavity and comprises an upper member, a lower member, and a mating room. The mating room is located between the upper member and the lower member. The upper-row elastic terminals are held on a lower surface of the upper member and comprise a plurality of upper-row elastic signal terminals, at least one upper-row elastic power terminal, and at least one upper-row elastic ground terminal. The upper-row elastic terminals are at the insulation housing. The lower-row elastic terminals are held on an upper surface of the lower member and comprise a plurality of lower-row elastic signal terminals, at least one lower-row elastic power terminal, and at least one lower-row elastic ground terminal. The lower-row elastic terminals are at the insulation housing. Wherein the upper-row elastic signal terminals are at the lower surface of the upper member for transmitting first signals, the lower-row elastic signal terminals are at the upper surface of the lower member for transmitting second signals, the specification for transmitting the first signals is conformed to the specification for transmitting the second signals, and the upper-row elastic terminals and the lower-row elastic terminals are point-symmetrical with a central point of the receiving cavity as the symmetrical center. 
     In conclusion, since the upper-row elastic terminals and the lower-row elastic terminals are arranged upside down, and the pin configuration of the upper-row elastic signal terminals is left-right reversal with respect to that of the lower-row elastic signal terminals. When the electrical plug connector is inserted into an electrical receptacle connector by a first orientation where an upper plane of the electrical plug connector is facing up, the upper-row elastic terminals of the electrical plug connector are in contact with upper-row plate signal terminals of the electrical receptacle connector. Conversely, when the electrical plug connector is inserted into the electrical receptacle connector by a second orientation where the upper plane of the electrical plug connector is facing down, the upper-row elastic terminals of the electrical plug connector are in contact with lower-row plate signal terminals of the electrical receptacle connector. Consequently, the inserting orientation of the electrical plug connector is not limited when inserting into an electrical receptacle connector. Besides, a plurality of clamping structures are extending and inserted into two sides of the mating room to be in contact with hook structures located at two sides of an electrical receptacle connector. Therefore, the clamping structures are connected to the metal shell for conduction and grounding. Furthermore, a grounding sheet is located on the insulation housing and between the upper-row elastic terminals and the lower-row elastic terminals, thus the crosstalk interference can be improved by the grounding sheet during signal transmission. 
     Detailed description of the characteristics and the advantages of the instant disclosure is shown in the following embodiments, the technical content and the implementation of the instant disclosure should be readily apparent to any person skilled in the art from the detailed description, and the purposes and the advantages of the instant disclosure should be readily understood by any person skilled in the art with reference to content, claims and drawings in the disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure will become more fully understood from the detailed description given herein below for illustration only, and thus are not limitative of the disclosure, and wherein: 
         FIG. 1  illustrates a perspective view of an electrical plug connector according to the instant disclosure, where the electrical plug connector is combined with an insulation casing and a cable; 
         FIG. 2  illustrates an exploded view of the electrical plug connector according to the instant disclosure, where the electrical plug connector is to be assembled with the insulation casing and the adapting cable; 
         FIG. 3  illustrates a partial cross-sectional view of the electrical plug connector according to the instant disclosure combined with the insulation casing; 
         FIG. 4A  illustrates a front sectional view of the electrical plug connector according to the instant disclosure; 
         FIG. 4B  is a schematic configuration diagram of the elastic terminals of the electrical plug connector shown in  FIG. 4A ; 
         FIG. 5  illustrates a perspective view of the electrical plug connector according to the instant disclosure, where the electrical plug connector is connected to a plurality of wires; 
         FIG. 6A  illustrates a perspective view of the electrical plug connector according to the instant disclosure, where the electrical plug connector is connected to a ground plate; 
         FIG. 6B  illustrates a perspective view of the electrical plug connector according to the instant disclosure, where the electrical plug connector is connected to a plurality of wires, for one variation; 
         FIG. 7A  illustrates a perspective view of the electrical plug connector according to the instant disclosure, where the electrical plug connector is combined with a cover piece; 
         FIG. 7B  illustrates a perspective view of the electrical plug connector according to the instant disclosure, where the electrical plug connector is combined with an insulation casing; 
         FIG. 8A  illustrates a perspective view of the electrical plug connector according to the instant disclosure, where the electrical plug connector is combined with an insulation casing, for one variation; 
         FIG. 8B  illustrates a partial exploded view of the electrical plug connector according to the instant disclosure, where the electrical plug connector is combined with an insulation casing, for one variation; 
         FIG. 9  is a front sectional view illustrating that the upper-row elastic terminals are offset with respect to the lower-row elastic terminals of the electrical plug connector according to the instant disclosure; 
         FIG. 10  illustrates a partial exploded view of the electrical plug connector provided with a frame portion; 
         FIG. 11  illustrates an exploded view of the electrical plug connector provided with a frame portion; 
         FIG. 12  illustrates a perspective view of the electrical plug connector provided with a tubular portion; 
         FIG. 13  illustrates a perspective view of the electrical plug connector provided with buckle holes; 
         FIG. 14  illustrates an exploded view of the electrical plug connector provided with the buckle holes; 
         FIG. 15  illustrates a perspective view of the electrical plug connector provided with extension sheets; 
         FIG. 16  illustrates an exploded view of the electrical plug connector combined with a clamping shell; 
         FIG. 17  illustrates a cross-sectional view of the electrical plug connector only provided with a plurality of upper-row elastic terminals; and 
         FIG. 18  illustrates a cross-sectional view of the electrical plug connector only provided with a plurality of lower-row elastic terminals. 
     
    
    
     DETAILED DESCRIPTION 
     Please refer to  FIGS. 1, 2 and 3 , illustrating exemplary embodiments of an electrical plug connector  100  according to the instant disclosure is combined with an insulation casing  71  and a cable  90 , but the embodiments are not thus limited thereto. In some embodiments, the electrical plug connector  100  may be combined with a circuit board  91  (shown as  FIG. 6A ) to form a flash drive or a vertical charging dock without the cable  90 .  FIG. 1  is a perspective view,  FIG. 2  is an exploded view, and  FIG. 3  is a partial cross-sectional view of the electrical plug connector. The electrical plug connector  100  according to the instant disclosure is in accordance with the specification of a USB type-C connection interface. In the embodiment, the electrical plug connector  100  mainly comprises a metal shell  11 , an insulation housing  21 , a plurality of upper-row elastic terminals  31 , and a plurality of lower-row elastic terminals  41 . 
     The metal shell  11  is a hollow shell and defines a receiving cavity  112  therein. In the embodiment, the metal shell  11  is formed by bending a unitary structured, main body  111 . In some embodiments, the main body  111  may be formed as a two-piece structure (as shown in  FIG. 11 ). The connection between the two pieces of the main body  111  can be formed by a dovetail manner (as shown in  FIG. 6B ), an overlapped manner, or an extruded manner. In addition after bending, the connection between the two pieces of the main body  111  can be lined up to each other or tilted toward the interior of the receiving cavity  112  (i.e., the connection between the two pieces of the main body  111  is formed as a V profile when viewing laterally). Besides, the metal shell  11  may be provided with a plurality of buckle holes  1111  formed on the surface of the main body  111  and defined through the surface of the metal shell  11  (as shown in  FIG. 14 ). Alternatively, in some embodiments, the metal shell  11  is devoid of the buckle holes  1111  (as shown in  FIG. 2 ). In addition, a plug opening  113 , in oblong shaped, is formed on one side of the metal shell  11  (as shown in  FIG. 2 ). Alternatively, a plug opening  113 , in rectangular shaped, is formed on one side of the metal shell  11  (as shown in  FIG. 6B ). Additionally, the plug opening  113  communicates with the receiving cavity  112 . 
     The insulation housing  21  is in the receiving cavity  112  and comprises a base portion  210 , an upper member  211 , a lower member  212 , and a mating room  213 . The base portion  210 , the upper member  211 , the lower member  212  described herein are formed by injection-molding, and defines the mating room  213  therebetween. Specifically, the upper member  211  and the lower member  212  are extending from one side of the base portion  210 . In addition, the mating room  213  is located between the upper member  211  and the lower member  212 . The upper member  211  is provided with a lower surface  2111  and an upper front lateral surface  2112 , the lower member  212  is provided with an upper surface  2121  and a lower front lateral surface  2122 . The lower surface  2111  of the upper member  211  is opposite to the upper surface  2121  of the lower member  212 . 
     Please refer to  FIG. 4A  and  FIG. 4B , in which the upper-row elastic terminals  31  comprises a plurality of upper-row elastic signal terminals  311 , at least one upper-row elastic power terminal  312  and at least one upper-row elastic ground terminal  313 . As shown in  FIG. 4B , the upper-row elastic terminals  31  comprise, from right to left, an upper-row elastic ground terminal  313  (Gnd), a first pair of differential signal terminals (TX1+−), a second pair of differential signal terminals (D+−), and a third pair of differential signal terminals (RX2+−), of the upper-row elastic signal terminals  311 , upper-row elastic power terminals  312  (Power/VBUS), between the three pairs of differential signal terminals, a retain terminal (RFU), (the retain terminal and a configuration channel 1 (CC1) are respectively arranged between the upper-row elastic power terminals  312  (Power/VBUS) and the second pair of differential signal terminals of the upper-row elastic signal terminals  311 ), and an upper-row elastic ground terminal  313  at the leftmost side. However, the pin configuration described herein is an example for illustrative purpose, but not a limitation. The electrical plug connector  100  described herein may comprise, but not limited to, twelve upper-row elastic terminals  31  for transmitting USB 3.0 signals. In some embodiments, the rightmost (or leftmost) upper-row elastic ground terminal  313  (Gnd) and the retain terminal (RFU) can be omitted. Besides, the rightmost upper-row elastic ground terminal  313  (Gnd) may be replaced by an upper-row elastic power terminal  312  (Power/VBUS) and provided for power transmission. Here, the width of the upper-row elastic power terminal  312  (Power/VBUS) may be, but not limited to, equal to the width of each of the upper-row elastic signal terminals  311 . In some embodiments, the width of the upper-row elastic power terminal  312  may be greater than the width of each of the upper-row elastic signal terminals  311  (as shown in  FIG. 15 ). Accordingly, the electrical plug connector  100  is applicable for an electronic product required for high current transmission. 
     Please refer to  FIG. 2  and  FIG. 3 , in which each of the upper-row elastic terminals  31  comprises an upper-row contact segment  315 , an upper-row connecting segment  314 , and an upper-row soldering segment  316 . For each upper-row elastic terminal  31 , the upper-row connecting segment  314  is at the upper member  211 , the upper-row contact segment  315  is extending from one of two ends of the upper-row connecting segment  314  and at the lower surface  2111  of the upper member  211 , and the upper-row soldering segment  316  is extending from the other end of the upper-row connecting segment  314  and protruded out of the insulation housing  21 . The upper-row elastic signal terminals  311  are extending toward the mating room  213  for transmitting first signals (i.e., USB 3.0 signals). The upper-row soldering segments  316  are protruded out of the rear part of the insulation housing  21 . Moreover, the upper-row soldering segments  316  are horizontally aligned and separated from the lower-row soldering segments  416 , so that the upper-row soldering segments  316  and the lower-row soldering segments  416  are formed as two lines. Alternatively, by bending the upper-row soldering segments  316 , the upper-row soldering segments  316  and the lower-row soldering segments  416  may be formed as one line. 
     Please refer to  FIG. 3 , in which embodiment the distance between the upper-row elastic power terminal  312  and the upper front lateral surface  2112  of the upper member  211  is equal to the distance between each of the upper-row elastic signal terminals  311  and the upper front lateral surface  2112  of the upper member  211 . In addition, the distance between the upper-row elastic ground terminal  313  and the upper front lateral surface  2112  of the upper member  211  is equal to the distance between each of the upper-row elastic signal terminals  311  and the upper front lateral surface  2112  of the upper member  211 . That is, each of the upper-row elastic terminals  31  described herein has an identical length, but embodiments are not thus limited thereto. 
     In some embodiments, the upper-row elastic terminals  31  are provided with different lengths (not shown). In other words, the distance between the upper-row elastic power terminal  312  and the upper front lateral surface  2112  of the upper member  211  is less than the distance between each of the upper-row elastic signal terminals  311  and the upper front lateral surface  2112  of the upper member  211 . Moreover, the distance between the upper-row elastic ground terminal  313  and the upper front lateral surface  2112  of the upper member  211  is less than the distance between each of the upper-row elastic signal terminals  311  and the upper front lateral surface  2112  of the upper member  211 . When the electrical plug connector  100  is plugged into an electrical receptacle connector, the upper-row elastic power terminal  312  or the upper-row elastic ground terminal  313  is preferentially in contact with the terminals of the electrical receptacle connector, and the upper-row elastic signal terminals  311  are then in contact with the terminals of the electrical receptacle connector. Accordingly, the electrical plug connector  100  is ensured to be completely plugged into the electrical receptacle connector (i.e., to be plugged into the electrical receptacle connector properly), before power or signal transmission. It should be understood that if the electrical plug connector  100  is not completely plugged into the electrical receptacle connector, arc burn may occur due to poor contact between the upper-row elastic signal terminal  311  and the terminals of the electrical receptacle connector. Therefore, based on the upper-row elastic terminals  31  with different lengths, the arc burn problem can be prevented. 
     Please refer to  FIG. 4A  and  FIG. 4B , in which the lower-row elastic terminals  41  comprises a plurality of lower-row elastic signal terminals  411 , at least one lower-row elastic power terminal  412 , and at least one lower-row elastic ground terminal  413 . As shown in  FIG. 4B , the lower-row elastic terminals  41  comprise, from left to right, a lower-row elastic ground terminal  413  (Gnd), a first pair of differential signal terminals (TX2+−), a second pair of differential signal terminals (D+−), and a third pair of differential signal terminals (RX1+−), of the lower-row elastic signal terminals  411 , lower-row elastic power terminals  412  (Power/VBUS), between the three pairs of differential signal terminals, a retain terminal (RFU), (the retain terminal and a configuration channel 2 (CC2) are respectively arranged between the lower-row elastic power terminals  412  (Power/VBUS) and the second pair of differential signal terminals of the lower-row elastic signal terminals  411 ), and a lower-row elastic ground terminal  413  (Gnd) at the rightmost side. However, the pin configuration described herein is an example for illustrative purpose, but not a limitation. The electrical plug connector  100  described herein may include, but not limited to, twelve lower-row elastic terminals  41  for transmitting USB 3.0 signals. In some embodiments, the rightmost (or leftmost) lower-row elastic ground terminal  413  (Gnd) and the retain terminal (RFU) can be omitted. Besides, the leftmost lower-row elastic ground terminal  413  (Gnd) can be replaced by a lower-row elastic power terminal  412  (Power/VBUS) and provided for power transmission. Here, the width of the lower-row power terminal  412  (Power/VBUS) may be, but not limited to, equal to that of each of the lower-row elastic signal terminals  411 . In some embodiments, the width of the lower-row elastic power terminal  412  can also be greater than that of each of the lower-row elastic signal terminals  411  (as shown in  FIG. 15 ). Accordingly, the electrical plug connector is applicable for the electronic product required for high current transmission. 
     Please refer to  FIG. 2  and  FIG. 3 , in which each of the lower-row elastic terminals  41  comprises a lower-row contact segment  415 , a lower-row connecting segment  414 , and a lower-row soldering segment  416 . For each lower-row elastic terminal  41 , the lower-row connecting segment  414  is at the lower member  212 , the lower-row contact segment  415  is extending from one of two ends of the lower-row connecting segment  414  and at the upper surface  2121  of the lower member  212 , and the lower-row soldering segment  416  is extending from the other end of the lower-row connecting segment  414  and protruded out of the insulation housing  21 . The lower-row elastic signal terminals  41  are extending toward the mating room  213  for transmitting second signals (i.e., USB 3.0 signals). The lower-row soldering segments  416  are protruded out of the rear part of the insulation housing  21 . Moreover, the lower-row soldering segments  316  are horizontally aligned. 
     Please refer to  FIG. 3 , in which embodiment, the distance between the lower-row elastic power terminal  412  and the lower front lateral surface  2122  of the lower member  212  is equal to the distance between each of the lower-row elastic signal terminals  411  and the lower front lateral surface  2122  of the lower member  212 . Moreover, the distance between the lower-row elastic ground terminal  413  and the lower front lateral surface  2122  of the lower member  212  is equal to the distance between each of the lower-row elastic signal terminals  411  and the lower front lateral surface  2122  of the lower member  212 . That is, each of the lower-row elastic terminals  41  described herein has an identical length, but embodiments are not thus limited thereto. 
     In some embodiments, the lower-row elastic terminals  41  are provided with different lengths (not shown). In other words, the distance between the lower-row elastic power terminal  412  and the lower front lateral surface  2122  of the lower member  212  is less than the distance between each of the lower-row elastic signal terminals  411  and the lower front lateral surface  2122  of the lower member  212 , and, the distance between the lower-row elastic ground terminal  413  and the lower front lateral surface  2122  of the lower member  212  is less than the distance between each of the lower-row elastic signal terminals  411  and the lower front lateral surface  2122  of the lower member  212 . When the electrical plug connector  100  is plugged into the electrical receptacle connector, the lower-row elastic power terminal  412  or the lower-row elastic ground terminal  413  is preferentially in contact with the terminals of the electrical receptacle connector, and the lower-row elastic signal terminal  411  are then in contact with the terminals of the electrical receptacle connector. Accordingly, the electrical plug connector  100  is ensured to be completely plugged into the electrical receptacle connector (i.e., to be plugged into the electrical receptacle connector properly), before power or signal transmission. It should be understood that if the electrical plug connector  100  is not completely plugged into the electrical receptacle connector, arc burn may occur due to poor contact between the lower-row elastic signal terminal  413  and the terminals of the electrical receptacle connector. Therefore, based on the lower-row elastic terminals  41  with different lengths, the arc burn problem can be prevented. 
     Please refer back to  FIG. 2 ,  FIG. 3 ,  FIG. 4A  and  FIG. 4B , in which embodiment the upper-row elastic terminals  31  and the lower-row elastic terminals  41  are respectively at the lower surface  2111  of the upper member  211  and the upper surface  2121  of the lower member  212 . Additionally, pin configuration of the upper-row elastic terminals  31  and the lower-row elastic terminals  41  are point-symmetrical with a central point of the receiving cavity  112  as the symmetrical center. Here, point-symmetry means that after the upper-row elastic terminals  31  (or the lower-row elastic terminals  41 ), are rotated by 180 degrees with the symmetrical center as the rotating center, the upper-row elastic terminals  31  and the lower-row elastic terminals  41  are overlapped. That is, the rotated upper-row elastic terminals  31  are arranged at the position of the original lower-row elastic terminals  41 , and the rotated lower-row elastic terminals  41  are arranged at the position of the original upper-row elastic terminals  31 . In other words, the upper-row elastic terminals  31  and the lower-row elastic terminals  41  are arranged upside down, and the pin configuration of the upper-row elastic terminals  31  are left-right reversal with respect to that of the lower-row elastic terminals  41 . The electrical plug connector  100  is inserted into an electrical receptacle connector with a first orientation where the upper plane of the electrical plug connector  100  is facing up (i.e., the lower surface  2111  of the upper member  211  is facing down), for transmitting first signals. Conversely, the electrical plug connector  100  is inserted into the electrical receptacle connector with a second orientation where the upper plane of the electrical plug connector  100  is facing down (i.e., the upper surface  2121  of the lower member  212  is facing up), for transmitting second signals. Besides, the specification for transmitting the first signals is conformed to the specification for transmitting the second signals. Note that, the inserting orientation of the electrical plug connector  100  is not limited by the electrical receptacle connector. 
     Furthermore, in some embodiments, when an electrical receptacle connector to be mated with the electrical plug connector is provided with plural upper-row terminals and lower-row terminals, the electrical plug connector  100  may be devoid of the upper-row elastic terminals  31  or the lower-row elastic terminals  41  (as shown in  FIG. 17  and  FIG. 18 ). Regarding the upper-row elastic terminals  31  are omitted, when the electrical plug connector  100  is inserted into the electrical receptacle connector with the first orientation or the second orientation, the lower-row elastic terminals  41  of the electrical plug connector  100  are in contact with the upper-row terminals or the lower-row terminals of the electrical receptacle connector. Conversely, regarding the lower-row elastic terminals  41  are omitted, when the electrical plug connector  100  is inserted into the electrical receptacle connector with the first orientation or the second orientation, the upper-row elastic terminals  31  of the electrical plug connector  100  are in contact with the upper-row terminals or the lower-row terminals of the electrical receptacle connector. Accordingly, the inserting orientation of the electrical plug connector  100  is not limited by the orientation of the electrical receptacle connector. 
     Please refer to  FIG. 3 , in which embodiment, the upper-row soldering segments  316  and the lower-row soldering segments  416  are protruded out of the rear part of the insulation housing  21  to be separately arranged. The upper-row soldering segments  316  and the lower-row soldering segments  416  may be, but not limited to, arranged into two parallel lines, one by one. Here, each of the upper-row elastic terminals  31  is provided with an upper-row bending segment  317  extending between the upper-row connecting segment  314  and the upper-row soldering segment  316 , and the upper-row bending segments  317  are provided for adjusting the distance between the upper-row soldering segments  316  and the lower-row soldering segments  416 . Alternatively, each of the lower-row elastic terminals  41  may be provided with a lower-row bending segment  417  extending between the lower-row connecting segment  414  and the lower-row soldering segment  416 , and the lower-row bending segments  417  are provided for adjusting the distance between the lower-row soldering segments  416  and the upper-row soldering segments  316 . Accordingly, The upper-row soldering segments  316  and the lower-row soldering segments  416  can be directly connected to a plurality of wires  92  by soldering means (as shown in  FIG. 5 ), or can be soldered on the circuit board  91  (as shown in  FIG. 6A  and  FIG. 6B ). Moreover, the upper-row bending segments  317  and the lower-row bending segments  417  enable the distance between the upper-row soldering segments  316  and the lower-row soldering segments  416  being adjustable. Additionally, the bending segments  317 ,  417  also allow proper spatial arrangement of the terminals and high-frequency characteristic. Here, the distance between the upper-row soldering segments  316  and the lower-row soldering segments  416  is greater than, or equal to over three times of the width of each of the upper-row elastic terminals  31  (or each of the lower-row elastic terminals  41 ). In addition, the distance between the upper-row elastic terminals  31  and the lower-row elastic terminals  41  can be 0.6 mm, 0.8 mm, or 1.0 mm. 
     Please refer to  FIG. 2 ,  FIG. 3 , and  FIG. 4A , in which embodiment, the position of the upper-row elastic terminals  31  corresponds to the position of the lower-row elastic terminals  41 , as shown in  FIG. 4A . In other words, in the embodiment, the upper-row contact segments  315  are aligned to the lower-row contact segments  415 , one by one, but embodiments are not thus limited. In some embodiments, the upper-row contact segments  315  are aligned parallel to the lower-row contact segments  415 , and the upper-row contact segments  315  are offset with respect to the lower-row contact segments  415  (as shown in  FIG. 9 ). Similarly, the upper-row soldering segments  316  may be offset with respect to the lower-row soldering segments  416 . Therefore, crosstalk interference can be effectively improved with the offset configuration between the contact segments  315 ,  415  during signal transmission. Particularly, regarding the upper-row elastic terminals  31  and the lower-row elastic terminals  41  are configured with an offset, the terminals of the electrical receptacle connector would have to be configured correspondingly (i.e., the upper-row terminals and the lower-row terminals of the electrical receptacle connector are configured with an offset). Thus, the upper-row terminals and the lower-row terminals of the electrical receptacle connector can be correspondingly in contact with the upper-row elastic terminals  31  and the lower-row elastic terminals  41  for power or signal transmission. 
     In the above embodiments, the upper-row elastic terminals  31  or the lower-row elastic terminals  41  may be, but not limited to, provided for transmitting the USB 3.0 signals, individually. In some embodiments, for the upper-row elastic terminals  31 , the first pair of differential signal terminals (TX1+−) and the third pair of differential signal terminals (RX2+−) of the upper-row elastic signal terminals  311  can be omitted, and the second pair of differential signal terminals (D+−) and the upper-row elastic power terminal  312  (Power/VBUS) are retained, when transmitting USB 2.0 signals. For the lower-row elastic terminals  41 , the first pair of differential signal terminals (TX2+−) and the third pair of differential signal terminals (RX1+−) of the lower-row elastic signal terminals  411  can also be omitted, and the second pair of differential signal terminals (D+−) and the lower-row power terminal  412  (Power/VBUS) are retained, when transmitting USB 2.0 signals. 
     Please refer to  FIG. 2  and  FIG. 3 . In some embodiments, the electrical plug connector  100  is combined with a rear plugging member  13 . The rear plugging member is fixed at the rear part of the insulation housing  21 . From a side view of the rear plugging member  13 , the rear plugging member  13  is formed as a U-profile structure. The rear plugging member  13  defines a plurality of through grooves  131  therethrough, and the upper-row soldering segments  316  and the lower-row soldering segments  416  are held in the through grooves  131 . That is, the rear plugging member  13  is fitted over the upper-row soldering segments  316  and the lower-row soldering segments  416  to enclose the periphery of the soldering segments  316 ,  416 . Accordingly, when the electrical plug connector  100  is wrapped with an outer mould (e.g., a cover piece  94  in  FIG. 7A ), the rear plugging member  13  prevents glues of the outer mould from flowing out of the space between the upper-row soldering segments  316  and the lower-row soldering segments  416 . 
     Please refer to  FIG. 3 ,  FIG. 5 , and  FIG. 4B . In some embodiments, the electrical plug connector  100  is further connected to the wires  92 . When the upper-row soldering segments  316  and the lower-row soldering segments  416  are exposed out of the through grooves  131  of the rear plugging member  13 , the wires  92  can be correspondingly soldered with the upper-row soldering segments  316  and the lower-row soldering segments  416  on the rear plugging member  13 . In addition, the wires  92  connected to the electrical plug connector  100  can be of a coaxial structure, and the wires  92  can be soldered to the soldering segments  316 ,  416  via means of hot bar soldering, hot air fixing, or automatic ultrahigh-frequency soldering. 
     The electrical plug connector  100  combined with the rear plugging member  13  and soldered with the wires  92  described above is for illustrative purpose, embodiments are not limited thereto. In some embodiments, the electrical plug connector  100  may be combined with the circuit board  91  and devoid of the rear plugging member  13  (as shown in  FIG. 6A ). Here, the circuit board  91  is fixed at the rear part of the insulation housing  21 . In other words, one of two sides of the circuit board  91  is soldered with the upper-row soldering segments  316  and the lower-row soldering segments  416  (as shown in  FIG. 6A  and  FIG. 6B ), and the other side of the circuit board  91  is connected to the wires  92 . Here, a plurality of upper-surface contacts  911  is located on one of two surfaces of the circuit board  91  and connected to the upper-low soldering segments  316 . Likewise, a plurality of lower-surface contacts  912  is located on the other surface of the circuit board  91  and connected to the lower-row soldering segments  416 . The wires  92  may be soldered on at least one of the two surfaces of the circuit board  91 . Particularly, the circuit board  91  is further provided with a plurality of ground contacts  913  used for grounding, the metal shell  11  is soldered with the ground contacts  913 , and a ground wire  921  of the wires  92  is soldered with the ground contacts  913 . 
     Please refer to  FIG. 6A  and  FIG. 6B . In some embodiments, a plurality of fixing grooves  117  is defined at the rear part of the metal shell  11 . The fixing grooves  117  are cut elongate grooves formed on the two sides of the metal shell  11 . The width of each of the fixing grooves  117  is greater than the thickness of the circuit board  91 , so that two sides of the circuit board  91  are held in the fixing grooves  117 . 
     Please refer to  FIG. 6A  and  FIG. 6B . In some embodiments, the electrical plug connector  100  is further provided with a ground plate  95 . The ground plate  95  is a strip-shaped plate and integrated with the wires  92 . The ground plate  95  is provided with a plurality of rods  951  protruded therefrom, at least one of the rods  951  is extending toward and in contact with at least one of ground contacts  913 , and the rods  951  are further extending toward and in contact with the upper-surface contacts  911  of the circuit board  91 . Accordingly, regarding the number of the wires  92  is reduced, the rods  951  are in contact with the upper-surface contacts  911  when the wires  92  are soldered with the upper-surface contacts  911 . 
     Please refer to  FIG. 6A  and  FIG. 6B . In some embodiments, the electrical plug connector  100  may be further combined with a fixing plate  93  when connecting to the wires  92 . The fixing plate  93  is an elongate case. Here, plural fixing plates  93  are combined to the top and the bottom of the rear part of the circuit board  91 , and the wires  92  may be then fixed with the fixing plates  93 . The fixing between the wires  92  and the fixing plates  93  may be carried out with following means. In one embodiment, the fixing plates  93  are combined with the wires  92  during insert-molding. In one variation, the fixing plates  93  are buckled with the wires  92 . Or, the fixing plates  93  are fixed with the wires  92  via an auxiliary tool. 
     Please refer to  FIG. 7A  and  FIG. 7B . In some embodiments, the electrical plug connector  100  may be further combined with the cover piece  94  (an inner mould) and the insulation casing  71  (the outer mould). The cover piece  94  covers the wires  92 , the upper-row soldering segments  316 , and the lower-row soldering segments  416 . When the wires  92  are soldered on the circuit board  91 , the cover piece  94  may be combined with the electrical plug connector  100  by means of gluing or over-molding. Therefore, the wires  92 , the upper-row soldering segments  316 , and the lower-row soldering segments  416  are securely fixed to the circuit board  91 . Besides, the insulation casing  71  is further combined with the electrical plug connector  100  by means of over-molding, so that the wires  92  and the rear part of the metal shell  11  are enclosed properly. Accordingly, an electrical plug connector  100  provided with the wire  92  is carried out. 
     In some embodiments, the insulation casing  71  may be a unitary structure (as shown in  FIG. 2  and  FIG. 7 ) or a two-piece structure (as shown in  FIG. 8A  and  FIG. 8B ). Regarding the insulation casing  71  being a two-piece structure, the insulation casing  71  comprises a front cover  711  and a rear cover  712  (as shown in  FIGS. 8A and 8B ). The front cover  711  and the rear cover  712  can be combined with each other by means of gluing, buckling, or a combination of the foregoing two means. Alternatively, a further outer mould may be applied to enclose the front cover  711  and the rear cover  712  for the combination of the front cover  711  and the rear cover  712 . 
     Please refer to  FIG. 3 . In some embodiments, the electrical plug connector  100  is further provided with a grounding sheet  51  at the insulation housing  21 . The grounding sheet  51  comprises a body portion  511  and a plurality of pins  512 . The body portion  511  is located between the upper-row elastic terminals  31  and the lower-row elastic terminals  41  to separate the upper-row elastic terminals  31  from the lower-row elastic terminals  41 . The pins  512  are extending from the two sides of the body  511 , exposed out of the insulation housing  21 , and in contact with the metal shell  11  or the circuit board  91 . Accordingly, the crosstalk interference can be improved due to the grounding sheet  51  during signal transmission. 
     Please refer to  FIG. 2  and  FIG. 3 . In some embodiments, the electrical plug connector  100  is further provided with a plurality of clamping structures  52  at the two sides of the insulation housing  21 . Each of the clamping structures  52  comprises a projecting hook portion  521  and a projecting contact portion  522 . The projecting hook portions  521  are fixed at the two sides of the insulation housing  21 . The outer surface of each of the projecting hook portions  521  is in contact with the metal shell  11 . Here, each of the projecting hook portions  521  is provided with an inverse barbed bump  5211 , a round bump  5212 , and an elastic sheet  5213 , but embodiments are not limited thereto. In implementation, each of the projecting hook portions  521  may be provided with at least one of the inverse barbed bump  5211 , the round bump  5212 , and the elastic sheet  5213 . The projecting hook portions  521  are assembled to the insulation casing  21 . In addition, the projecting contact portions  522  are extending from the front portions of the projecting hook portions  521  and inserted into the two sides of the mating room  213 . Accordingly, when the electrical plug connector  100  is plugged into the electrical receptacle connector, a plurality of hook structures at the two sides of the electrical receptacle connector can be in contact with the projecting contact portions  522 . Therefore, the projecting hook portions  521  are in contact with the metal shell  11  to provide conduction and grounding. 
     Please refer to  FIG. 12 . In some embodiments, the metal shell  11  is provided with a tubular portion  114  forward extending from the front end of the plug opening  113 , and innerly narrowed in the radial direction. Here, the tubular portion  114  may be formed on the metal shell  11  by applying a suitable deep drawing technique to a conductive metal sheet to gradually deform the conductive metal sheet by repeated operations. When the electrical plug connector  100  is plugged into the electrical receptacle connector, the outer lateral surface of the tubular portion  113  would be in contact with a plurality of conductive plates of the electrical receptacle connector, so that the tubular portion  113  and the metal shell  11  are combined with each other for conduction and grounding. Accordingly, the EMI problem can be reduced. 
     Please refer to  FIG. 2 . In some embodiments, the metal shell  11  is further provided with an inclined guiding surface  1131  at the outer lateral surface of the plug opening  113 . The metal shell  11  can be provided with the inclined guiding surface  1131  by applying a drawing or stamping technique. The inclined guiding surface  1131  facilitates the connection between the electrical plug connector  100  and the electrical receptacle connector when the electrical plug connector  100  is to be inserted into the electrical receptacle connector, but embodiments are not limited thereto. In some embodiments, the insulation housing  21  is provided with a frame portion  215  (as shown in  FIG. 10  and  FIG. 11 ). The frame portion  215  is extending from the front end of the insulation housing  21 . In other words, the frame portion  215  is extending from the front portions of the upper member  211  and the lower member  212  to surround the periphery of the plug opening  113 . The frame portion  215  is provided with an inclined guiding surface  2151 . When the electrical plug connector  100  is plugged into the electrical receptacle connector, the electrical receptacle connector can be in contact with the inclined guiding surface  2151  of the frame portion  215  to facilitate the connection between the electrical plug connector  100  and the electrical receptacle connector. 
     Please refer to  FIG. 13  and  FIG. 14 . In some embodiments, the metal shell  11  is further provided with a main body  111  and a plurality of buckle holes  1111 . The buckle holes  1111  are formed on the main body  111  and adjacent to the plug opening  113 . The metal shell  11  can be provided with the buckle holes  1111  in a half-stamping technique or a stamping technique. When the electrical plug connector  100  is plugged into the electrical receptacle connector, the elastic sheets of the electrical receptacle connector are buckled into the buckle holes  1111 . In addition, the metal shell  11  is further provided with a plurality of extension sheets  1112  (as shown in  FIG. 15 ). Each of the extension sheets  1112  is connected between opposite inner walls of the corresponding buckle hole  1111 . Accordingly, the elastic sheets of the electrical receptacle connector are buckled onto the extension sheets  1112 . 
     Please refer to  FIG. 16 . In some embodiments, the electrical plug connector  100  may be further combined with a clamping shell  61 . The metal shell  11  is provided with a rear-end clamping piece  115 . The clamping shell  61  is combined with the rear-end clamping piece  115  to enclose the wire  92 . Accordingly, the clamping shell  61  is combined with the metal shell  21 , where the clamping shell  61  may be a unitary structure or a multi-piece structure. 
     In conclusion, since the upper-row elastic terminals and the lower-row elastic terminals are arranged upside down, and the pin configuration of the upper-row elastic signal terminals is left-right reversal with respect to that of the lower-row elastic signal terminals. When the electrical plug connector is inserted into an electrical receptacle connector by a first orientation where an upper plane of the electrical plug connector is facing up, the upper-row elastic terminals of the electrical plug connector are in contact with upper-row plate signal terminals of the electrical receptacle connector. Conversely, when the electrical plug connector is inserted into the electrical receptacle connector by a second orientation where the upper plane of the electrical plug connector is facing down, the upper-row elastic terminals of the electrical plug connector are in contact with lower-row plate signal terminals of the electrical receptacle connector. Consequently, the inserting orientation of the electrical plug connector is not limited when inserting into an electrical receptacle connector. Besides, a plurality of clamping structures are extending and inserted into two sides of the mating room to be in contact with hook structures located at two sides of an electrical receptacle connector. Therefore, the clamping structures are connected to the metal shell for conduction and grounding. Furthermore, a grounding sheet is located on the insulation housing and between the upper-row elastic terminals and the lower-row elastic terminals, thus the crosstalk interference can be improved by the grounding sheet during signal transmission. 
     While the disclosure has been described by the way of example and in terms of the preferred embodiments, it is to be understood that the instant disclosure need not be limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims, the scope of which should be accorded the broadest interpretation so as to encompass all such modifications and similar structures.