Patent Publication Number: US-10777952-B2

Title: Electrical plug connector

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This non-provisional application claims priority under 35 U.S.C. § 119(a) to patent application Ser. No. 10/7,209,072 in Taiwan, R.O.C. on Jul. 4, 2018, the entire contents of which are hereby incorporated by reference. 
     FIELD OF THE INVENTION 
     The instant disclosure relates to an electrical connector, and more particular 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 by end users. Now, as technology innovation marches forward, new kinds of devices, media formats and large inexpensive storage are converging. They require significantly more bus bandwidth to maintain the interactive experience that users have come to expect. In addition, the demand of a higher performance between the PC and the sophisticated peripheral is increasing. The transmission rate of USB 2.0 is insufficient. As a consequence, faster serial bus interfaces such as USB 3.0, are developed, which may provide a higher transmission rate so as to satisfy the need of a variety devices. 
     The appearance, the structure, the contact ways of terminals, the number of terminals, the pitches between terminals (the distances between the terminals), and the pin assignment of terminals of a conventional USB type-C electrical connector are totally different from those of a conventional USB electrical connector. A USB type-C electrical plug connector known to the inventor includes a plastic core, upper and lower plug terminals held on the plastic core, an outer iron shell circularly enclosing the plastic core, and conductive sheets held on the plastic core. 
     SUMMARY OF THE INVENTION 
     Upon signal transmission, high-frequency noises produced by upper and lower terminals of a USB type-C electrical plug connector known to the inventor may resonate with nearby radio-frequency signals easily via the grounding loops of the connector, and the operations of the peripheral devices among the connector may be affected. 
     In view of this, an embodiment of the instant disclosure provides an electrical plug connector. The electrical plug connector comprises a metallic shell, a first terminal module, a second terminal module, and a metallic contact member. The first terminal module comprises a first insulated member and a plurality of first plug terminals. An inner surface of the first insulated member comprises a plurality of first terminal grooves for positioning the first plug terminals. The second terminal module is assembled with the first terminal module and received in a receiving cavity of the metallic shell. The second terminal module comprises a second insulated member and a plurality of second plug terminals. An inner surface of the second insulated member comprises a plurality of second terminal grooves for positioning the second plug terminals. The contact member is between the first plug terminals and the second plug terminals. Two ends of the contact member respectively comprise a contact finger. The contact fingers contact first ground terminals of the first plug terminals or contact second ground terminals of the second plug terminals. 
     In one or some embodiments, each of the contact fingers at the two ends of the metallic contact member has an elastic arm extending outwardly. 
     In one or some embodiments, the first insulated member comprises a first combining block formed on the inner surface of the first insulated member to retain the first plug terminals. Two ends of the first combining block comprise a plurality of recesses for receiving the elastic arms. 
     In one or some embodiments, each of the first plug terminals comprises a first flexible contact portion, a first body portion, and a first tail portion. Each of the first body portions is held in the first combining block. The first body portion of each of the first ground terminals is in contact with the corresponding elastic arm. Each of the first flexible contact portions is extending forward from the corresponding first body portion in the rear-to-front direction, and each of the first tail portions is extending backward from the corresponding first body portion in the front-to-rear direction and extending out of the first combining block. 
     In one or some embodiments, the metallic contact member comprises a grounding plate and a separation plate separated with each other. The grounding plate is between the first insulated member and the second insulated member, and two ends of the separation plate comprise the contact fingers. 
     In one or some embodiments, the separation plate comprises a plurality of engaging members extending outwardly, and at least one of the engaging members is in contact with the grounding plate. 
     In one or some embodiments, the second insulated member comprises a second combining block formed on the inner surface of the second insulated member to retain the second plug terminals. Two ends of the second combining block comprise a plurality of buckling grooves for receiving the engaging members. 
     In one or some embodiments, each of the second plug terminals comprises a second flexible contact portion, a second body portion, and a second tail portion. Each of the second body portions is held in the second combining block, the second body portion of each of the second ground terminals is in contact with the corresponding elastic arm. Each of the second flexible contact portions is extending forward from the corresponding second body portion in the rear-to-front direction, and each of the second tail portions is extending backward from the corresponding second body portion in the front-to-rear direction and extending out of the second combining block. 
     In one or some embodiments, each of the first ground terminals comprises a first bending portion contacting the metallic contact member, and each of the second ground terminals comprises a second bending portion contacting the metallic contact member. 
     Another embodiment of the instant disclosure provides an electrical plug connector. The electrical plug connector comprises a metallic shell, a first terminal module, a second terminal module, and a metallic contact member. The first terminal module comprises a first insulated member and a plurality of first plug terminals. An inner surface of the first insulated member comprises a plurality of first terminal grooves in a vertical direction for positioning the first plug terminals. The second terminal module is assembled with the first terminal module and received in a receiving cavity of the metallic shell. The second terminal module comprises a second insulated member and a plurality of second plug terminals. An inner surface of the second insulated member comprises a plurality of second terminal grooves in the vertical direction for positioning the second plug terminals. The metallic contact member is between the first insulated member and the second insulated member, and the metallic contact member is between the first plug terminals and the second plug terminals. The metallic contact member comprises at least one contact finger, and the at least one contact finger contacts one of first ground terminals of the first plug terminals or one of second ground terminals of the second plug terminals. The metallic contact member further comprises a grounding plate and a separation plate. The grounding plate further comprises a pair of side latches. Each of the pair of the side latches comprises a locking head and a side arm. The side arms are extending forwardly from two sides of the grounding plate and sidewardly extending inwardly toward the insertion cavity in a transverse direction perpendicular to the vertical direction, so that the side arms are adapted to lock with a metallic shielding plate of an electrical receptacle connector into which the electrical plug connector is inserted. 
     In one or some embodiments, the separation plate comprises the at least one contact finger, and the at least one contact finger contacts one of the first ground terminals or one of the second ground terminals. 
     In one or some embodiments, the separation plate comprises at least one engaging member extending outwardly and the at least one engaging member is in contact with the grounding plate. 
     In one or some embodiments, the first insulated member comprises a first combing block formed on the inner surface of the first insulated member to retain the first plug terminal. Two ends of the first combining block comprise a plurality of recesses for receiving the at least one contact fingers. 
     In one or some embodiments, the separation plate comprises a plurality of engaging members extending outwardly. At least one of the engaging members is in contact with the grounding plate. 
     In one or some embodiments, the second insulated member comprises a second combining block formed on the inner surface of the second insulated member to retain the second plug terminals. Two ends of the second combining block comprise a plurality of buckling grooves for receiving the engaging members. 
     In one or some embodiments, the first insulated member comprises a first combining block formed on the inner surface of the first insulated member to retain the first plug terminals, the second insulated member comprises a second combining block formed on the inner surface of the second insulated member to retain the second plug terminals. A pair of protruding posts and a pair of assembled holes are respectively formed on one side of the first combining block and one side of the second combining block in the vertical direction. The grounding plate has through holes for inserting the protruding posts. The pair of protruding posts and the pair of assembled holes are mated with each other, the assemble the first insulated member, the grounding plate, and the second insulated member together. 
     In one or some embodiments, the electrical plug connector further comprises a first conductive sheet and a second conductive sheet. The first conductive sheet is combined with an outer surface of the first insulated member. The second conductive sheet is combined with an outer surface of the second insulated member. The first conductive sheet comprises a plurality of first elastic arms inserted into the insertion cavity. The second conductive sheet comprises a plurality of second elastic arms inserted into the insertion cavity. 
     In one or some embodiments, the first conductive sheet further comprises a plurality of protruding points contacting an inner surface of the metallic shell, and the second conductive sheet further comprises a plurality of protruding points contacting the inner surface of the metallic shell. 
     According to one or some embodiment of the instant disclosure, the contact member is between the first insulated member and the second insulated member, and the contact member is also between the first plug terminals and the second plug terminals. Hence, the contact member separates the first plug terminals from the second plug terminals. Furthermore, the two ends of the contact member are respectively in contact with the ground terminals of the first plug terminals or in contact with the ground terminals of the second plug terminals. Accordingly, because of the contact between the contact member and the ground terminal, high-frequency noises can be prevented from resonating with the nearby radio-frequency signals via the grounding loops of the electrical plug connector when the electrical plug connector transmits signals. 
     Furthermore, the first plug terminals and the second plug terminals are arranged upside down, and the pin-assignment of the flexible contact portions of the first plug terminals is left-right reversal with respect to that of the flexible contact portions of the second plug terminals. Accordingly, the electrical plug connector can have a 180 degree symmetrical, dual or double orientation design and pin assignments which enables the electrical plug connector to be mated with a corresponding receptacle connector in either of two intuitive orientations, i.e. in either upside-up or upside-down directions. Therefore, when the electrical plug connector is inserted into the electrical receptacle connector with a first orientation, the first flexible contact portions are in contact with upper-row receptacle terminals of the electrical receptacle connector. Conversely, when the electrical plug connector is inserted into the electrical receptacle connector with a second orientation, the second flexible contact portions are in contact with the upper-row receptacle terminals of the electrical receptacle connector. Note that, the inserting orientation of the electrical plug connector is not limited by the electrical receptacle connector. 
     Detailed description of the characteristics and the advantages of the instant disclosure are 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 instant disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The instant disclosure will become more fully understood from the detailed description given herein below for illustration only, and thus not limitative of the instant disclosure, wherein: 
         FIG. 1  illustrates a perspective view of an electrical plug connector according to an exemplary embodiment of the instant disclosure; 
         FIG. 2  illustrates an exploded view ( 1 ) of the electrical plug connector of the exemplary embodiment; 
         FIG. 3  illustrates a partial assembled view of the electrical plug connector of the exemplary embodiment; 
         FIG. 4  illustrates a perspective view showing that a contact member is in contact with a first ground terminal, according to the electrical plug connector of the exemplary embodiment; 
         FIG. 5  illustrates a lateral sectional view of the electrical plug connector of the exemplary embodiment; 
         FIG. 6  illustrates an exploded view ( 2 ) of the electrical plug connector of the exemplary embodiment; 
         FIG. 7  illustrates a perspective view of a first embodiment of the contact member of the electrical plug connector of the exemplary embodiment; 
         FIG. 8  illustrates a perspective view of a second embodiment of the contact member of the electrical plug connector of the exemplary embodiment; 
         FIG. 9  illustrates a perspective view showing a first embodiment of the contact between the contact member and the first ground terminal, according to the electrical plug connector of the exemplary embodiment; 
         FIG. 10  illustrates a perspective view showing a first embodiment of the contact between the contact member and the second ground terminal, according to the electrical plug connector of the exemplary embodiment; 
         FIG. 11  illustrates a perspective view showing a second embodiment of the contact between the contact member and the first ground terminal, according to the electrical plug connector of the exemplary embodiment; 
         FIG. 12  illustrates a perspective view showing a second embodiment of the contact between the contact member and the second ground terminal, according to the electrical plug connector of the exemplary embodiment; and 
         FIG. 13  illustrates a perspective view showing on embodiment of the contact between the contact member, the first ground terminal, and the second ground terminal, according to the electrical plug connector of the exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Please refer to  FIGS. 1 to 3 , illustrating an electrical plug connector  100  according to an exemplary embodiment of the instant disclosure.  FIG. 1  illustrates a perspective view thereof,  FIG. 2  illustrates an exploded view ( 1 ) thereof, and  FIG. 3  illustrates a partial assembled view thereof. In this embodiment, the electrical plug connector  100  can provide a reversible or dual orientation USB Type-C connector interface and pin assignments, i.e., a USB Type-C plug connector. Furthermore, the electrical plug connector  100  may be assembled with a circuit board and provided as a flash disk, but embodiments are not limited thereto. In one embodiment, the electrical plug connector  100  may be used in a transmission cable. In this embodiment, the electrical plug connector  100  comprises a metallic shell  1 , a first terminal module  2 , a second terminal module  4 , and a metallic contact member  8 . 
     Please refer to  FIGS. 1, 2, and 5 .  FIG. 5  illustrates a lateral sectional view of the electrical plug connector  100  of the exemplary embodiment. In this embodiment, the metallic shell  1  is a hollowed shell. The metallic shell  1  comprises a receiving cavity  11 . The first terminal module  2  and the second terminal module  4  are received in the receiving cavity  11  of the metallic shell  1 . 
     Please refer to  FIGS. 2 to 6 .  FIG. 4  illustrates a perspective view showing that the metallic contact member  8  is in contact with a first ground terminal  33  of the first terminal module  2 .  FIG. 6  illustrates an exploded view ( 2 ) of the electrical plug connector  100  of the exemplary embodiment. In this embodiment, the first terminal module  2  comprises a first insulated member  21 , a plurality of first plug terminals  3 , a first combining block  25 , and a first conductive sheet  27 . The first conductive sheet  27  is a metallic member and is formed on the first insulated member  21 . The first conductive sheet  27  is a EMC (Electromagnetic Compatibility) spring which is a shielding strip having EMC spring fingers. The first insulated member  21  is combined with the first conductive sheet  27  (the first insulated member  21  and the first conductive sheet  27  may be separated components or insert-molding as a one-piece component). In this embodiment, the first conductive sheet  27  and the first insulated member  21  is combined together by insert-molding process. 
     Please refer to  FIGS. 2 to 6 . An inner surface of the first insulated member  21  comprises assembled holes  251 . In this embodiment, the inner surface of the first insulated member  21  comprises a plurality of first terminal grooves  23  in a vertical direction for positioning the first plug terminals  3 . The first combining block  25  is formed on the inner surface of the first insulated member  21  for retaining the first plug terminals  3 . The assembled holes  251  are formed on one side of the first combining block  25  in the vertical direction. 
     Please refer to  FIGS. 2 to 6 . In this embodiment, the first plug terminals  3  comprise a plurality of signal terminals  31 , at least one power terminal  32 , and a plurality of ground terminals  33 . Alternatively, the first plug terminals  3  may comprise a plurality of signal terminals  31 , at least one power terminal  32 , and at least one ground terminal  33 . 
     Please refer to  FIGS. 2 to 6 . In this embodiment, the second terminal module  4  comprises a second insulated member  41 , a plurality of second plug terminals  5 , a second combining block  45 , and a second conductive sheet  47 . The second conductive sheet  47  is a metallic member and is formed on the second insulated member  41 . The second conductive sheet  47  is a EMC (Electromagnetic Compatibility) spring which is a shielding strip having EMC spring fingers. The second insulated member  41  is combined with the second conductive sheet  47  (the second insulated member  41  and the second conductive sheet  47  may be separated components or insert-molding as a one-piece component). In this embodiment, the second conductive sheet  47  and the first insulated member  41  is combined together by insert-molding. 
     Please refer to  FIGS. 2 to 6 . In this embodiment, an inner surface of the second insulated member  41  comprises a protruding post  451  for mating with the assembled hole  251 . In this embodiment, the inner surface of the second insulated member  41  comprises a plurality of second terminal grooves  43  for positioning the second plug terminals  5  in the vertical direction. The second combining block  45  is formed on the inner surface of the second insulated member  41  for retaining the second plug terminals  5 . The protruding post  451  is formed on one side of the second combining block  45  in the vertical direction. 
     Please refer to  FIGS. 2 to 6 . In this embodiment, the second plug terminals  5  comprise a plurality of signal terminals  51 , at least one power terminal  52 , and a plurality of ground terminals  53 . Alternatively, the second plug terminals  5  may comprise a plurality of signal terminals  51 , at least one power terminal  52 , and at least one ground terminal  53 . 
     Please refer to  FIGS. 2 to 6 . In this embodiment, the first insulated member  21  is assembled with the second insulated member  41  to form a tubular structure  6  (as shown in  FIG. 1 ) for being inserted into the receiving cavity  11  of the metallic shell  1 . The tubular structure  6  has an insertion cavity  60  for mating with an electrical receptacle connector. 
     Please refer to  FIGS. 2 to 6 . In this embodiment, during a first molding process of the first terminal module  2 , the first insulated member  21  is combined with the first conductive sheet  27  by insert-molding process, and then the first plug terminals  3  are assembled on the first insulated member  21 . During a second molding process, the first combining block  25  is formed on the inner surface of the first insulated member  21  and assembled with the first plug terminals  3 , and then the metallic belting connected to the first conductive sheet  27  and the metallic belting connected to the first plug terminals  3  are removed. In addition, the first combining block  25  also can be an individual component assembled on the inner surface of the first insulated member  21  for retaining the first plug terminals  3 . After the first insulated member  21  is combined with the first conductive sheet  27  by insert-molding process, the metallic belting connected to the first conductive sheet  27  and the metallic belting connected to the first plug terminals  3  are removed. Then, the first combining block  25  is assembled on the inner surface of the first insulated member  21 . 
     Please refer to  FIGS. 2 to 6 . In this embodiment, during a first molding process of the second terminal module  4 , the second insulated member  41  is combined with the second conductive sheet  47  by insert-molding process, and then the second plug terminals  5  are assembled on the second insulated member  41 . During a second molding process, the second combining block  45  is formed on the inner surface of the second insulated member  41  and assembled with the second plug terminals  5 , and then the metallic belting connected to the second conductive sheet  47  and the metallic belting connected to the second plug terminals  5  are removed. In addition, the second combining block  45  also can be an individual component assembled on the inner surface of the second insulated member  41 . After the second insulated member  41  is combined with the second conductive sheet  47  by insert-molding process, the metallic belting connected to the second conductive sheet  47  and the metallic belting connected to the second plug terminals  5  are removed. Then, the second combining block  45  is assembled on the inner surface of the second insulated member  41 . 
     Please refer to  FIGS. 2 to 6 . In some embodiments, the first plug terminals  3  comprise a plurality of signal terminals  31 , at least one power terminal  32 , and at least one ground terminal  33 . From a front view of the first plug terminals  3 , the first plug terminals  3  comprise, from right to left, a ground terminal  33  (Gnd), a first pair high-speed signal terminals (TX1+−, differential signal terminals), a power terminal  32  (Power/VBUS), a first function detection terminal (CC 1 , a terminal for inserting orientation detection of the connector and for cable recognition), a pair of low-speed signal terminals (D+−, differential signal terminals), a first reserved terminal (RFU), another power terminal  32  (Power/VBUS), a second pair of high-speed signal terminals (RX2+−, differential signal terminals), and another ground terminal  33  (Gnd). 
     Please refer to  FIGS. 2 to 6 . In some embodiments, each of the first plug terminals  3  comprises a flexible contact portion  35 , a body portion  36 , and a tail portion  37 . In this embodiment, the body portions  36  are held in the first combining block  25 . The flexible contact portions  35  are extending forward from the body portions  36  in the rear-to-front direction and held in a plurality of first limiting grooves of the first terminal module  2 , and the tail portions  37  are extending backward from the body portions  36  in the front-to-rear direction and protruding out of the first combining block  25 . Each of the flexible contact portions  35  has a curved profile. The flexible contact portions  35  of the first plug terminals  3  are extending into the insertion cavity  60  for transmitting first signals (e.g., USB 3.0 signals or USB 4.0 signal). The tail portions  37  may be bent horizontally to form flat legs, named legs manufactured by SMT (surface mounted technology), which can be mounted or soldered on the surface of a printed circuit board (PCB) by using surface mount technology. Alternatively, the tail portions  37  may be extending downwardly to form vertical legs, named legs manufactured by through-hole technology, which can be inserted into holes drilled in a printed circuit board. 
     Please refer to  FIGS. 2 to 6 . In some embodiments, the second plug terminals  5  comprise a plurality of signal terminals  51 , at least one power terminal  52 , and at least one ground terminal  53 . From a front view of the second plug terminals  5 , the second plug terminals  5  comprise, from left to right, a ground terminal  53  (Gnd), a first pair high-speed signal terminals (TX2+−, differential signal terminals), a power terminal  52  (Power/VBUS), a second function detection terminal (CC 2 , a terminal for inserting orientation detection of the connector and for cable recognition), a pair of low-speed signal terminals (D+−, differential signal terminals), a second reserved terminal (RFU), another power terminal  52  (Power/VBUS), a second pair of high-speed signal terminals (RX1+−, differential signal terminals), and another ground terminal  53  (Gnd). 
     Please refer to  FIGS. 2 to 6 . In some embodiments, each of the second plug terminals  5  comprises a flexible contact portion  55 , a body portion  56 , and a tail portion  57 . In this embodiment, the body portions  56  are held in the second combining block  45 . The flexible contact portions  55  are extending forward from the body portions  56  in the rear-to-front direction and held in a plurality of second limiting grooves of the second terminal module  4 , and the tail portions  57  are extending backward from the body portions  56  in the front-to-rear direction and protruding out of the second combining block  45 . Each of the flexible contact portions  55  has a curved profile. The flexible contact portion  55  of the second plug terminals  5  are extending into the insertion cavity  60  for transmitting second signals (e.g., USB 3.0 signals or USB 4.0 signal). The tail portions  57  may be bent horizontally to form flat legs, named legs manufactured by SMT (surface mounted technology), which can be mounted or soldered on the surface of a printed circuit board (PCB) by using surface mount technology. Alternatively, the tail portions  57  may be extending downwardly to form vertical legs, named legs manufactured by through-hole technology, which can be inserted into holes drilled in a printed circuit board. 
     Please refer to  FIGS. 2 to 6 . In some embodiments, the first combining block  25  is combined with the body portions  36  of the first plug terminals  3  by insert-molding, and then the second combining block  45  is combined with the body portions  56  of the second plug terminals  5  by insert-molding process. Next, the metallic contact member  8  is assembled between the first combining block  25  and the second combining block  45 . Then, the assembly of the metallic contact member  8 , the first terminal module  2 , and the second terminal module  4  are assembled in the receiving cavity  11  of the metallic shell  1 . 
     Please refer to  FIGS. 2 to 6 . In some embodiments, the inner surface of the first insulated member  21  has the first limiting grooves at a front portion of the first terminal grooves  23 , and the inner surface of the second insulated member  41  has the second limiting grooves at a front portion of the second terminal grooves  43 . 
     Please refer to  FIGS. 2 to 6 . In some embodiments, the first plug terminals  3  and the second plug terminals  5  are respectively held on the lower surface of the first insulated member  21  (a first mating surface) and the upper surface of the second insulated member  41  (a second mating surface). Moreover, pin-assignments of the first plug terminals  3  and the second plug terminals  5  are point-symmetrical with a central point of the receiving cavity  11  as the symmetrical center. In other words, pin-assignments of the first plug terminals  3  and the second plug terminals  5  have 180-degree symmetrical design with respect to the central point of the receiving cavity  11  as the symmetrical center. The dual or double orientation design enables the electrical plug connector  100  to be inserted into an electrical receptacle connector in either of two intuitive orientations, i.e., in either upside-up or upside-down directions. Here, point-symmetry means that after the first plug terminals  3  (or the second plug terminals  5 ), are rotated by 180 degrees with the symmetrical center as the rotating center, the first plug terminals  3  and the second plug terminals  5  are overlapped. That is, the rotated first plug terminals  3  are arranged at the position of the original second plug terminals  5 , and the rotated second plug terminals  5  are arranged at the position of the original first plug terminals  3 . 
     In other words, the first plug terminals  3  and the second plug terminals  5  are arranged upside down, and the pin assignments of the first plug terminals  3  are left-right reversal with respect to that of the second plug terminals  51 . Therefore, the electrical plug connector  100  may be inserted into an electrical receptacle connector with a first orientation where the first mating surface is facing down, for transmitting first signals. Conversely, the electrical plug connector  100  may also be inserted into the electrical receptacle connector with a second orientation where the first mating surface is facing up, for transmitting second signals. Furthermore, 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 this embodiment, the flexible contact portions  35  of the first plug terminals  3  correspond to the flexible contact portions  55  of the second plug terminals  5 . 
     Please refer to  FIGS. 2 to 6 . In some embodiments, the first conductive sheet  27  is combined with an outer surface of the first insulated member  21 , and the second conductive sheet  47  is combined with an outer surface of the second insulated member  41 . The first conductive sheet  27  comprises a plurality of first elastic arms inserted into the insertion cavity  60  and a plurality of protruding points contacting an inner surface of the metallic shell  1 . The second conductive sheet  47  comprises a plurality of second elastic arms inserted into the insertion cavity  60  and a plurality of protruding points contacting the inner surface of the metallic shell  1 . 
     Please refer to  FIGS. 2 to 6  as well as  FIG. 10 .  FIG. 10  illustrates a perspective view showing a first embodiment of the contact between the metallic contact member  8  and the ground terminal  53  of the second plug terminals  5 , according to the electrical plug connector  100  of the exemplary embodiment. In some embodiments, the metallic contact member  8  is between the first insulated member  21  and the second insulated member  41 . The metallic contact member  8  is between the first plug terminals  3  and the second plug terminals  5 . Two ends of the metallic contact member  8  respectively comprise a contact finger  81  contacting each of the ground terminals  33  of the first plug terminals  3  or contacting each of the ground terminals  53  of the second plug terminals  5 . In one embodiment, the metallic contact member  8  is laid between twelve first plug terminals  3  and twelve second plug terminals  5 , and the contact fingers  81  at the two ends of the metallic contact member  8  are between the left and right outermost first plug terminals  3  of the twelve first plug terminals  3  or between the left and right outermost second plug terminals  5  of the twelve second plug terminals  5 . 
     Please refer to  FIGS. 2 to 6 . In some embodiments, each of the contact fingers  81  at the two ends of the metallic contact member  8  has an elastic arm  811  extending outwardly. Two ends of the first combining block  25  comprise a plurality of recesses  252  for receiving the elastic arms  811 . Moreover, the body portion  36  of each of the ground terminal  33  of the first plug terminals  3  is in contact with the corresponding elastic arm  811  of the metallic contact member  8  (as shown in  FIG. 9 ). 
     Please refer to  FIGS. 2 to 8 .  FIG. 7  illustrates a perspective view of a first embodiment of the metallic contact member  8  of the electrical plug connector  100  of the exemplary embodiment.  FIG. 8  illustrates a perspective view of a second embodiment of the metallic contact member  8  of the electrical plug connector  100  of the exemplary embodiment. In some embodiments, the metallic contact member  8  comprises a grounding plate  83  and a separation plate  85 , and the grounding plate  83  and the separation plate  85  may be formed integrally or separated with each other. The grounding plate  83  is between the first insulated member  21  and the second insulated member  41 . The grounding plate  83  has through holes  831  for inserting the protruding posts  451 . Two ends of the separation plate  85  respectively comprise the contact fingers  81 . 
     Please refer to  FIGS. 2 to 6 . In some embodiments, the grounding plate  83  is formed by blanking techniques, but embodiments are not limited thereto. In some embodiments, the grounding plate  83  may be formed by stamping techniques. A grounding plate  83  formed by blanking has a better structural strength than a grounding plate  83  formed by stamping. In addition, the grounding plate  83  comprises a pair of side latches  832 . The middle portion of the grounding plate  83  is a rectangular plate and a monolithic metallic shielding plate. Each of the side latches  832  is an elongate pin structure. The side latches  832  are symmetrical with each other, i.e., a first side latch  832  is mirrored with respect to its corresponding second side latch  832 . The side latches  832  are extending forwardly from two sides of the middle portion of the grounding plate  83  and sidewardly extending inwardly toward the insertion cavity  60  in a transverse direction perpendicular to the vertical direction for locking with a metallic shielding plate of an electrical receptacle connector into which the electrical plug connector  100  is inserted. Each of the side latches  832  further comprises a locking head, a side arm, and a contact leg. The locking head is at the front portion of each of the side latches  832  for contacting an electrical receptacle connector. The locking head is a hook structure. When the electrical plug connector  100  is inserted into the electrical receptacle connector, the locking heads of the side latches  832  can be used to lock with the metallic shielding plate of the electrical receptacle connector. Moreover, the contact leg is extending outwardly from the rear portion of each of the side latches  832 , and the contact legs are respectively extending out of the first insulated member  21  and the second insulated member  41  for contacting a circuit board. 
     Please refer to  FIGS. 2 to 6 . In some embodiments, the metallic contact member  8  comprises a plurality of engaging members  852  extending outwardly. At least one of engaging members  852  is in contact with the grounding plate  83 . Two ends of the second combining block  45  comprise a plurality of buckling grooves  452  for receiving the engaging members  852 . Moreover, the body portion  56  of each of the ground terminal  53  of the second plug terminals  5  is in contact with the corresponding elastic arm  811  of the metallic contact member  8  (as shown in  FIG. 10 ). 
     Please refer to  FIGS. 2 to 6  as well as  FIG. 11 .  FIG. 11  illustrates a perspective view showing a second embodiment of the contact between the metallic contact member  8  and the ground terminal  33  of the first plug terminals  3 , according to the electrical plug connector  100  of the exemplary embodiment. In some embodiments, each of the ground terminals  33  of the first plug terminals  3  comprises a first bending portion  331  contacting the corresponding contact finger  81 . The first bending portion  331  may be a curved portion protruding downwardly at the body portion  36  of each of the ground terminals  33  of the first plug terminals  3  and provided for contacting the metallic contact member  8 . 
     Please refer to  FIGS. 2 to 6  as well as  FIG. 12 .  FIG. 12  illustrates a perspective view showing a second embodiment of the contact between the metallic contact member  8  and the ground terminal  53  of the second plug terminals  5 , according to the electrical plug connector  100  of the exemplary embodiment. In some embodiments, each of the ground terminals  53  of the second plug terminals  5  comprises a second bending portion  531  contacting the corresponding contact finger  81 . The second bending portion  531  may be a curved portion protruding upwardly at the body portion  56  of each of the ground terminals  53  of the second plug terminals  5  and provided for contacting the metallic contact member  8 . 
     In some embodiments, the two ends of the metallic contact member  8  may be in contact with one ground terminal  33  of the first plug terminal  3  and one ground terminal  53  of the second plug terminal  5  (as shown in  FIG. 13 ). In some other embodiments, the two ends of the metallic contact member  8  may be in contact with two ground terminals  33  of the first plug terminals  3 . In some further other embodiments, the two ends of the metallic contact member  8  may be in contact with two ground terminals  53  of the second plug terminals  5 . In some embodiments, one of the two ends of the metallic contact member  8  comprises at least one first contact finger  81  contacting the at least one ground terminal  33  of the first plug terminals  3 , and the other end of the metallic contact member  8  comprises at least one second contact finger  81  contacting the at least one ground terminal  53  of the second plug terminals  5 . 
     According to one or some embodiment of the instant disclosure, the metallic contact member is between the first insulated member and the second insulated member, and the metallic contact member is also between the first plug terminals and the second plug terminals. Hence, the metallic contact member separates the first plug terminals from the second plug terminals. Furthermore, the two ends of the metallic contact member are respectively in contact with the ground terminals of the first plug terminals or in contact with the ground terminals of the second plug terminals. Accordingly, because of the contact between the metallic contact member and the ground terminal, high-frequency noises can be prevented from resonating with the nearby radio-frequency signals via the grounding loops of the electrical plug connector when the electrical plug connector transmits signals. 
     Furthermore, the first plug terminals and the second plug terminals are arranged upside down, and the pin-assignment of the flexible contact portions of the first plug terminals is left-right reversal with respect to that of the flexible contact portions of the second plug terminals. Accordingly, the electrical plug connector can have a 180 degree symmetrical, dual or double orientation design and pin assignments which enables the electrical plug connector to be mated with a corresponding receptacle connector in either of two intuitive orientations, i.e. in either upside-up or upside-down directions. Therefore, when the electrical plug connector is inserted into the electrical receptacle connector with a first orientation, the first flexible contact portions are in contact with upper-row receptacle terminals of the electrical receptacle connector. Conversely, when the electrical plug connector is inserted into the electrical receptacle connector with a second orientation, the second flexible contact portions are in contact with the upper-row receptacle terminals of the electrical receptacle connector. Note that, the inserting orientation of the electrical plug connector is not limited by the electrical receptacle connector. 
     While the instant disclosure has been described by the way of example and in terms of the preferred embodiments, it is to be understood that the invention 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.