Patent Publication Number: US-9853399-B2

Title: Electrical plug connector with shielding and grounding features

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an electrical plug connector, and more particularly, to an electrical plug connector adapted for a Universal Serial Bus interface and capable of reducing high frequency interferences and electromagnetic interferences. 
     2. Description of the Prior Art 
     With the development of computer and peripheral equipment industry, a Universal Serial Bus (USB) interface has become one of important interfaces for communication and data transmission between computers and peripheral equipment. As technology advances, high speed transmission is a trend, and there is a need to develop an electrical connector with high speed transmission. Furthermore, with the trend of an electrical device with thin thickness, the electrical connector with thin thickness is required. The electrical connector with high speed transmission and thin thinness results in high frequency interferences (HFIs) and electromagnetic interferences (EMIs) among contacts of the electrical connector or between the coupled electrical connectors. Thus, it impacts on performance of high frequency transmission or high speed transmission between a USB electrical plug connector and a USB electrical receptacle connector and may impact on normal performance of an electrical device to which the aforesaid connectors are coupled, such as a Bluetooth device, a mobile phone, a laptop, a tablet, or a hard disc drive. Therefore, it has become an important topic to design a new USB electrical plug connector with thin thinness, high speed transmission, and reliability as well as capability of reducing HFIs and EMIs due to thin thickness and high speed transmission of the electrical connectors. 
     SUMMARY OF THE INVENTION 
     The present invention provides an electrical plug connector, and more particularly, to an electrical plug connector adapted for a Universal Serial Bus interface and capable of reducing high frequency interferences and electromagnetic interferences for solving above drawbacks. 
     According to the claimed invention, an electrical plug connector includes a plug metal shell, an insulation housing bracket, a first plug grounding contact and a first grounding member. The insulation housing bracket is combined with the plug metal shell and has a first side. The first plug grounding contact is held inside the insulation housing bracket. The first grounding member is disposed between the plug metal shell and the first plug grounding contact and spaced from the first side of the insulation housing bracket. The first grounding member mechanically contacts with the first plug grounding contact, such that the first grounding member is electrically connected to the first plug grounding contact. 
     According to the claimed invention, the first grounding member includes a first connecting structure protruding from the first grounding member and contacting with the first plug grounding contact, such that the first grounding member is electrically connected to the first plug grounding contact. 
     According to the claimed invention, the first connecting structure is a protrusion portion or a spring arm, and the first connecting structure and the first grounding member are integrally formed. 
     According to the claimed invention, the first plug grounding contact includes a first connecting structure protruding from the first grounding contact and contacting with the first grounding member, such the first grounding member is electrically connected to the first plug grounding contact. 
     According to the claimed invention, the first connecting structure is a contact bending structure, and the first connecting structure and the first plug grounding contact are integrally formed. 
     According to the claimed invention, the insulation housing bracket has a second side opposite to the first side, and the electrical plug connector further includes a second plug grounding contact and a second grounding member. The second plug grounding contact is held inside the insulation housing bracket and corresponding to the first plug grounding contact. The second grounding member is disposed between the plug metal shell and the second plug grounding contact and spaced from the second side of the insulation housing bracket. The second grounding member mechanically contacts with the second plug grounding contact, such that the second grounding member is electrically connected to the second plug grounding contact. 
     According to the claimed invention, the second grounding member includes a second connecting structure protruding from the second grounding member and contacting with the second plug grounding contact, such that the second grounding member is electrically connected to the second plug grounding contact. The second connecting structure is a protrusion portion or a spring arm, and the second connecting structure and the second grounding member are integrally formed. 
     According to the claimed invention, the second plug grounding contact includes a second connecting structure protruding from the second grounding contact and contacting with the second grounding member, such the second grounding member is electrically connected to the second plug grounding contact. The second connecting structure is a contact bending structure, and the second connecting structure and the second plug grounding contact are integrally formed. 
     According to the claimed invention, an accommodating space is enclosed by the plug metal shell, and the electrical plug connector further includes an insulation housing disposed inside the accommodating space. An internal socketing space is enclosed by the insulation housing and for accommodating the first plug grounding contact and the second plug grounding contact. 
     According to the claimed invention, the first grounding member further includes a first grounding body and a first abutting portion. The first grounding body is installed on the insulation housing. The first abutting portion protrudes from the first grounding body. The first abutting portion abuts against the plug metal shell, such that the first grounding body is electrically connected to the plug metal shell. 
     According to the claimed invention, the second grounding member further includes a second grounding body and a second abutting portion. The second grounding body is installed on a side of the insulation housing and opposite to the first grounding body. The second abutting portion protrudes from the second grounding body. The second abutting portion abuts against the plug metal shell, such that the second grounding body is electrically connected to the plug metal shell. 
     According to the claimed invention, the first grounding member further includes a first resilient portion extending from an end of the first grounding body and stretching into the internal socketing space. The second grounding member further includes a second resilient portion extending from an end of the second grounding body and stretching into the internal socketing space. 
     According to the claimed invention, the first grounding member further includes a first mounting leg protruding from the first grounding body and embedding into the insulation housing. The second grounding member further includes a second mounting leg protruding from the second grounding body and embedding into the insulation housing. 
     According to the claimed invention, the electrical plug connector further includes a first signal contact set, a second signal contact set and a shielding member. The first signal contact set is arranged alongside the first plug grounding contact. The second signal contact set is arranged alongside the second plug grounding contact. The shielding member is disposed between the first signal contact set and the second signal contact set. The shielding member is for shielding the first signal contact set and the second signal contact set. 
     According to the claimed invention, the insulation housing bracket includes a first insulator and a second insulator. The second insulator is detachably assembled on the first insulator, and the first insulator and the second insulator clamp the shielding member cooperatively. 
     According to the claimed invention, the first insulator includes a first protruding pillar and a first engaging hole formed thereon. The second insulator includes a second protruding pillar and a second engaging hole formed thereon. A first through hole and a second through hole are formed on the shielding member. The first protruding pillar engages with the second engaging hole via the first through hole, and the second protruding pillar engages with the first engaging hole via the second through hole. 
     According to the claimed invention, the shielding member includes a shielding body, a resilient hook and a grounding portion. The resilient hook extends from the shielding body and is for hooking an electrical receptacle connector. The grounding portion extends from a side of the shielding body and is opposite to the resilient hook. The grounding portion is coupled to a circuit board. 
     According to the claimed invention, an electrical plug connector includes a plug metal shell, a first terminal module, a second terminal module, an insulation housing and a first grounding member. An accommodating space is enclosed by the plug metal shell. The first terminal module includes a first insulator, a first signal contact and two first plug grounding contacts. The first signal contact set is held inside the first insulator. The two first plug grounding contacts are held inside the first insulator and arranged alongside the first signal contact set. The two first plug grounding contacts are disposed on two opposite sides of the first signal contact set respectively. The second terminal module includes a second insulator, a second signal contact set and two second grounding contacts. The second insulator is assembled with the first insulator to form an insulation housing bracket. The second signal contact set is held inside the second insulator. The two second grounding contacts are held inside the second insulator and arranged alongside the second signal contact set. The two second grounding contacts are disposed on two opposite sides of the second signal contact set respectively. The insulation housing is disposed inside the accommodating space. An internal socketing space is enclosed by the insulation housing and for accommodating the first plug grounding contact and the second plug grounding contact. The first grounding member is disposed between the plug metal shell and the first plug grounding contact, and spaced from the first side of the insulation housing bracket. The first grounding member mechanically contacts with the first plug grounding contact, such that the first grounding member is electrically connected to the first plug grounding contact. 
     According to the claimed invention, each of the first signal contact set and the second signal contact set includes at least two pairs of differential signal contacts. The differential signal contacts of the first signal contact set is symmetric to the differential signal contacts of the second signal contact set by rotational of 180 degrees along a front-back direction of the electrical plug connector. 
     In contrast to the prior art, the present invention utilizes the first connecting structure and the first abutting portion for electrically connecting the plug metal shell, the first grounding member, and the first plug grounding contact. The present invention further utilizes the second connecting structure and second abutting portion for electrically connecting the plug metal shell, the second grounding member, and the second plug grounding contact. In such a way, electromagnetic noises and electromagnetic interferences can be reduced when the electrical plug connector transmits high frequency signals or high speed signals, such that performance of high frequency transmission or high speed transmission of the electrical plug connector is improved. Furthermore, the present invention further utilizes the shielding member disposed between the first signal contact set and the second signal contact set for shielding the first signal contact set and the second signal contact set and for preventing interferences and crosstalk therebetween. 
     These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram of an electrical plug connector according to a first embodiment of the present invention. 
         FIG. 2  is a diagram of the electrical plug connector according the first embodiment of the present invention. 
         FIG. 3  and  FIG. 4  are exploded diagrams of the electrical plug connector in different views according to the first embodiment of the present invention. 
         FIG. 5  is a sectional diagram of the electrical plug connector according to the first embodiment of the present invention. 
         FIG. 6  and  FIG. 7  are sectional diagrams of the electrical plug connector and an electrical receptacle connector in different views according to the first embodiment of the present invention. 
         FIG. 8  is an exploded diagram of the electrical plug connector according to a second embodiment of the present invention. 
         FIG. 9  is a sectional diagram of the electrical plug connector according to the second embodiment of the present invention. 
         FIG. 10  is an exploded diagram of the electrical plug connector according to a third embodiment of the present invention. 
         FIG. 11  is a sectional diagram of the electrical plug connector according to the third embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. In this regard, directional terminology, such as “top,” “bottom,” “front,” “back,” etc., is used with reference to the orientation of the Figure (s) being described. The components of the present invention can be positioned in a number of different orientations. As such, the directional terminology is used for purposes of illustration and is in no way limiting. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive. 
     Please refer to  FIG. 1  to  FIG. 4 .  FIG. 1  is a schematic diagram of an electrical plug connector  3000  according to a first embodiment of the present invention.  FIG. 2  is a diagram of the electrical plug connector  3000  according the first embodiment of the present invention.  FIG. 3  and  FIG. 4  are exploded diagrams of the electrical plug connector  3000  in different views according to the first embodiment of the present invention. As shown in  FIG. 1  to  FIG. 4 , the electrical plug connector  3000  includes a plug metal shell  1 , a first terminal module  2 A, a second terminal module  2 B, a first grounding member  4 , a second grounding member  7 , and a shielding member B. The first terminal module  2 A includes a first insulator  22 , two first plug grounding contacts  3 A,  3 B and a first signal contact set  5 . The two first plug grounding contacts  3 A,  3 B and the first signal contact set  5  are held inside the first insulator  22 . The first insulator  22  includes a first base portion  223  and a first tongue portion  224 . Fixing portions of the two first plug grounding contacts  3 A,  3 B and the first signal contact set  5  are held inside the first insulator  22 . Resilient portions of the two first plug grounding contacts  3 A,  3 B and the first signal contact set  5  extend forwardly from the fixing portions thereof along a front-back direction of the electrical plug connector  3000 , and end portions of the two first plug grounding contacts  3 A,  3 B and the first signal contact set  5  extend backwardly from the fixing portions thereof along the front-back direction of the electrical plug connector  3000 . 
     The second terminal module  2 B includes a second insulator  23 , two second plug grounding contacts  6 A,  6 B and a second signal contact set  8 . The two second plug grounding contacts  6 A,  6 B and the second signal contact set  8  are held inside the second insulator  23 . The second insulator  23  includes a second base portion  233  and a second tongue portion  234 . Fixing portions of the two second plug grounding contacts  6 A,  6 B and the second signal contact set  8  are held inside the second insulator  23 . Resilient portions of the two second plug grounding contacts  6 A,  6 B and the second signal contact set  8  extend forwardly from the fixing portions along the front-back direction of the electrical plug connector  3000 , and end portions of the two second plug grounding contacts  6 A,  6 B and the second signal contact set  8  extend backwardly from the fixing portions along the front-back direction of the electrical plug connector  3000 . The first plug grounding contacts  3 A,  3 B and the first signal contact set  5  can be held inside the first insulator  22  in an insert-molding manner or in an assembling manner, and the second grounding contacts  6 A,  6 B and the second signal contact set  8  can be held inside the second insulator  23  in an insert-molding manner or in an assembling manner respectively. Furthermore, the second insulator  23  is detachably assembled on the first insulator  22 , and the first insulator  22  and the second insulator  23  clamp the shielding member B cooperatively. The shielding member B is disposed between the first insulator  22  and the second insulator  23 . The first insulator  22  is assembled with the second insulator  23  to form an insulation housing bracket  2 . The insulation housing bracket  2  has a first side  20  and a second side  21  opposite to the first side  20 , i.e., the first side  20  is located on the first tongue portion  224  of the first insulator  22 , and the second side  21  is located on the second tongue portion  234  of the second insulator  23 . 
     Please refer to  FIG. 3  to  FIG. 7 .  FIG. 5  is a sectional diagram of the electrical plug connector  3000  according to the first embodiment of the present invention.  FIG. 6  and  FIG. 7  are sectional diagrams of the electrical plug connector  3000  and an electrical receptacle connector  4000  in different views according to the first embodiment of the present invention. As shown in  FIG. 3  to  FIG. 7 , the electrical plug connector  3000  further includes an insulation housing D. An internal socketing space S′ is enclosed by the insulation housing D and for accommodating the first plug grounding contacts  3 A,  3 B, the first signal contact set  5 , the second plug grounding contacts  6 A,  6 B, and the second signal contact set  8 . The resilient portions of the first plug grounding contacts  3 A,  3 B, the first signal contact set  5 , the second plug grounding contacts  6 A,  6 B, and the second signal contact set  8  stretch into the internal socket space S′ from a rear side of the insulation housing D along the front-back direction of the electrical plug connector  3000 . The first tongue portion  224  and the second tongue portion  234  are accommodated inside an accommodation space (not shown in figures) formed on the rear side of the insulation housing D. Furthermore, an accommodating space S is enclosed by the plug metal shell  1 . The insulation housing D, the first plug grounding contacts  3 A,  3 B, the first signal contact set  5 , the second plug grounding contacts  6 A,  6 B, the second signal contact set  8 , the first tongue portion  224  and the second tongue portion  234  are disposed in the accommodating space S. The first terminal module  2 A and the second terminal module  2 B are combined with the plug metal shell  1 . A rear side of the plug metal shell  1  abuts against a first abutting surface  223 A of the first base portion  223  of the first insulator  22  and a second abutting surface  233 A of the second base portion  233  of the second insulator  23 . 
     In addition, the first grounding member  4  includes a first grounding body  40  and a pair of first mounting legs  41 , and the second grounding member  7  includes a second grounding body  70  and a pair of second mounting legs  71 . The first grounding body  40  of the first grounding member  4  is installed on a top side of the insulation housing D, i.e., the top side is the same as the first side  20  of the insulation housing bracket  2 . In other words, the first grounding member  4  is installed on the top side of the insulation housing D, located between the plug metal shell  1  and the first plug grounding contacts  3 A,  3 B and spaced from the first side  20  of the first tongue portion  224  of the first insulator  22  of the insulation housing bracket  2 . The first mounting leg  41  protrudes from the first grounding body  40 . When the first grounding member  4  is installed on the insulation housing D, the first mounting leg  41  embeds into the insulation housing D for mounting the first grounding member  40  onto the insulation housing D. The second grounding body  70  of the second grounding member  7  is installed on a bottom side of the insulation housing D and away from the first grounding member  40 , i.e., the bottom side is the same as the second side  21  of the insulation housing bracket  2 . In other words, the second grounding member  7  is installed on the bottom side of the insulation housing D, located between the plug metal shell  1  and the second plug grounding contacts  6 A,  6 B and spaced from the second side  21  of the second tongue portion  234  of the second insulator  23  of the insulation housing bracket  2 . The second mounting leg  71  protrudes from the second grounding body  70 . When the second grounding member  7  is installed on the insulation housing D, the second mounting leg  71  embeds into the insulation housing D for mounting the second grounding body  70  onto the insulation housing D. The first grounding member  4  further includes two first connecting structures  4 A,  4 B. The first connecting structures  4 A,  4 B are formed on the first grounding body  40  and protrude from the first grounding body  40  of the first grounding member  4  toward the first plug grounding contacts  3 A,  3 B. The second grounding member  7  further includes two second connecting structures  7 A,  7 B. The second connecting structures  7 A,  7 B are formed on the second grounding body  70  and protrude from the second grounding body  70  of the second grounding member  7  toward the second plug grounding contacts  6 A,  6 B. 
     It should be noted that, in this embodiment, the first plug grounding contacts  3 A,  3 B are located on two opposite sides of the first signal contact set  5  and the first connecting structures  4 A,  4 B are disposed on lateral sides of the first grounding body  40  of the first grounding member  4  and located corresponding to the first plug grounding contacts  3 A and  3 B, i.e., the first connecting structures  4 A,  4 B are configured at locations corresponding to the first plug grounding contacts  3 A,  3 B. Therefore, the first connecting structures  4 A,  4 B can mechanically contact with the first grounding member  4  and the first plug grounding contacts  3 A,  3 B via the internal socketing space S′ enclosed by the insulation housing D when the first grounding member  4  is installed on the insulation housing D. In this embodiment, the first connecting structures  4 A,  4 B can be protrusion portions connected to the first grounding body  40  of the first grounding member  4 . In other words, when the first grounding member  4  is installed on the insulation housing D, the protrusion portions (i.e., the first connecting structures  4 A,  4 B) can abut against the first plug grounding contacts  3 A,  3 B, such that the protrusion portions are connected to the first grounding member  4  and the first plug grounding contacts  3 A,  3 B. In this embodiment, two first passing holes D 1 , D 2  are formed on the insulation housing D and located corresponding to the first connecting structures  4 A,  4 B and the first plug grounding contacts  3 A,  3 B. Accordingly, the first connecting structures  4 A,  4 B are able to contact with the first grounding member  4  via the passing holes D 1 , D 2 . 
     Furthermore, the first grounding member  4  further includes a first abutting portion  42  protruding from the first grounding body  40 . The first abutting portion  42  is for abutting against the plug metal shell  1 , such that the first grounding body  40  is electrically connected to the plug metal shell  1 . 
     Since the plug metal shell  1  and the first grounding member  4  are made of metal material, the first grounding member  4  is electrically connected to the first plug grounding contacts  3 A,  3 B, such that electromagnetic noises accumulated on the plug metal shell  1  is conducted to the first plug grounding contacts  3 A,  3 B when the first grounding member  4  shields signal contact sets (i.e., the first signal contact set  5  and the second signal contact set  8 ) and the plug metal shell  1  of the electrical plug connector  3000 . Accordingly, the electromagnetic noises are grounded to be eliminated for reducing electromagnetic interferences of the electrical plug connector  3000  during high frequency transmission, which improves performance of high frequency transmission or high speed transmission of the electrical plug connector  3000 . In practical applications, the first connecting structures  4 A,  4 B can be resilient members protruding from the first grounding member  4  or integrally formed with the first grounding member  4 , but the present invention is not limited to thereto. 
     Similarly, in this embodiment, the second plug grounding contacts  6 A,  6 B are located on two opposite sides of the second signal contact set  8 , and the second connecting structures  7 A,  7 B are disposed on lateral sides of the second grounding body  70  of the second grounding member  7  and corresponding to the second plug grounding contacts  6 A,  6 B. In other words, the second connecting structures  7 A,  7 B are configured corresponding to the second plug grounding contacts  6 A,  6 B. Therefore, when the second grounding member  7  is installed on the insulation housing D, the second connecting structures  7 A,  7 B can mechanically contact with the second grounding member  7  and the second plug grounding contacts  6 A,  6 B via the internal socketing space S′ of the insulation housing D. In this embodiment, the second connecting structures  7 A,  7 B are protrusion portions connected to the second grounding body  70  of the second grounding member  7 . In other words, when the second grounding member  7  is installed on the insulation housing D, the protrusion portions (i.e., the second connecting structures  7 A,  7 B) can abut against the second plug grounding contacts  6 A,  6 B, such that the protrusion portions is able to mechanically contact with the second grounding member  7  and the second plug grounding contacts  6 A,  6 B. In this embodiment, two second passing holes D 3 , D 4  are formed on the insulation housing D and located corresponding to the second connecting structures  7 A,  7 B and to the second plug grounding contacts  6 A,  6 B, such that the second connecting structures  7 A,  7 B is able to contact with the second grounding member  7  via the second passing holes D 3 , D 4 . 
     In addition, the second grounding member  7  includes a second abutting portion  72  protruding from the second grounding body  70 . The second abutting portion  72  is for abutting against the plug metal shell  1 , such that the second grounding body  70  is electrically connected to the plug metal shell  1 . In this embodiment, each of the first abutting portion  42  and the second abutting portion  72  can respectively be a spring arm, but the present invention is not limited thereto. 
     Since the plug metal shell  1  and the second grounding member  7  are made of metal material, the second grounding member  7  is electrically connected to the second plug grounding contacts  6 A,  6 B, such that electromagnetic noises accumulated on the plug metal shell  1  is conducted to the second plug grounding contacts  6 A,  6 B via the second grounding member  7  when the second grounding member  7  shields the signal contact sets (i.e., the first signal contact set  5  and the second signal contact set  8 ) and the plug metal shell  1 . The electromagnetic noises on plug metal shell  1  are grounded to be eliminated for reducing electromagnetic interferences of the electrical plug connector  3000  during high frequency transmission, which improves performance of high frequency transmission or high speed transmission of the electrical plug connector  3000 . In practical applications, the second connecting structures  7 A,  7 B can be resilient members protruding from the second grounding member  7  or integrally formed with the second grounding member  7 , but the present invention is not limited to thereto. 
     In summary, the first abutting portion  42  can electrically conduct the electromagnetic noises accumulated on the plug metal shell  1  to the first plug grounding contacts  3 A,  3 B via the first grounding body  40  when the signal contact sets (i.e. the first signal contact set  5  and the second signal contact set  8 ) of the electrical plug connector  3000  are in high frequency transmission. The second abutting portion  72  can also conduct the electromagnetic noises accumulated on the plug metal shell  1  to the second plug grounding contacts  6 A,  6 B via the second grounding body  70  when the signal contact sets (i.e. the first signal contact set  5  and the second signal contact set  8 ) of the electrical plug connector  3000  are in high frequency transmission. In such a way, the electromagnetic noises on the plug metal shell  1  are grounded to be eliminated by the first plug grounding contacts  3 A,  3 B or by the second plug grounding contacts  6 A,  6 B, which improves performance of high frequency transmission or high speed transmission of the electrical plug connector  3000 . 
     Furthermore, the first grounding member  4  further includes three first resilient portions  43  protruding from a side of the first grounding body  40 . The second grounding member  7  further includes three second resilient portions  73  protruding from a side of the second grounding body  70  and stretching into the internal socketing space S′, respectively. When the first grounding member  4  is installed on the insulation housing D, the first resilient portion  43  stretches into the internal socketing space S′. Accordingly, the first resilient portion  43  can resiliently abut against a third metal shielding member  401  covering an outer side of an insulation housing bracket of the electrical receptacle connector  4000  when the electrical plug connector  3000  is mated with the electrical receptacle connector  4000 . In such a manner, the third metal shielding member  401  located on the outer side of the insulation housing bracket of the electrical receptacle connector  4000 , the first grounding member  4 , and the first plug grounding contacts  3 A,  3 B are electrically connected. Similarly, when the second grounding member  7  is installed on the insulation housing D, the second resilient portion  73  stretches into the internal socketing space S′. Accordingly, the second resilient portion  73  can resiliently abut against a fourth metal shielding member  402  covering an outer side of the insulation housing bracket of the electrical receptacle connector  4000  when the electrical plug connector  3000  is connected to the electrical receptacle connector  4000 . In such a manner, the fourth metal shielding member  402  located on the outer side of the insulation housing bracket of the electrical receptacle connector  4000 , the second grounding member  7 , and the second plug grounding contacts  6 A,  6 B are electrically connected. The third metal shielding member  401  and the fourth metal shielding member  402  can be electrically connected to a receptacle metal shell of the electrical receptacle connector  4000 , respectively. In such a way, a shield is formed between the signal contact sets of the electrical plug connector  3000  and of the electrical receptacle connector  4000 , so as to prevent electromagnetic interferences and crosstalk. 
     As shown in  FIG. 2  to  FIG. 5 , the first grounding member  4  is disposed between the plug metal shell  1  and the insulation housing D, i.e., the first grounding member  4  is located between a top wall  10  of the plug metal shell  1  and the insulation housing D. The first connecting structures  4 A,  4 B are disposed on the first grounding member  4 . The second grounding member  7  is disposed between the plug metal shell  1  and the insulation housing D, i.e., the second grounding member  7  is located between a bottom wall  11  of the plug metal shell  1  and the insulation housing D. The second connecting structures  7 A,  7 B are disposed on the first grounding member  7 . It should be noted that the numbers of the first plug grounding contacts  3 A,  3 B, the first connecting structures  4 A,  4 B, the second plug grounding contacts  6 A,  6 B and the second connecting structures  7 A,  7 B of the present invention are not limited to those illustrated in figures in this embodiment. For example, the electrical plug connector  3000  can only include one first plug grounding contact, one first connecting structure, one second grounding contact and one second connecting structure. Structures with the aforesaid designs are within the scope of the present invention. 
     As shown in  FIG. 3  to  FIG. 7 , the first signal contact set  5  is arranged alongside the first plug grounding contacts  3 A,  3 B. The first plug grounding contacts  3 A,  3 B are located on two opposite sides of the first signal contact set  5 . Pin assignment from left to right of the first signal contact set  5  and the first plug grounding contacts  3 A,  3 B is the first plug grounding contact (GND)  3 A, a pair of first differential signal contacts (RX 2 +, RX 2 −), a first power contact (VBUS), a first auxiliary signal contact (SBU 1 ), a pair of second differential signal contacts (D−, D+), a positioning contact (CC), a power contact (VBUS), a pair of third differential signal contacts (TX 1 −, TX 1 +) and the first plug grounding contact (GDN)  3 B. The second signal contact set  8  is arranged alongside the first plug grounding contacts  6 A,  6 B. The second plug grounding contacts  6 A,  6 B are located on two opposite sides of the second signal contact set  8 . Pin assignment from left to right of the second signal contact set  8  and the first plug grounding contacts  6 A,  6 B is the second plug grounding contact (GND)  6 A, a pair of fourth differential signal contacts (TX 2 +, TX 2 −), a second power contact (VBUS), an auxiliary power contact (VCONN), a second auxiliary signal contact (SBU 2 ), a third power contact (VBUS), a pair of fifth differential signal contacts (RX 1 −, RX 1 +), and the second plug grounding contact (GDN)  6 B. There is no signal contact (i.e., a pair of differential signal contacts (D−, D+)) disposed between the second auxiliary power contact (VCONN) and the second auxiliary signal contact (SBU 2 ), such that the second auxiliary power contact (VCONN) is spaced from the second auxiliary signal contact set (SBU 2 ). In other words, the first signal contact set  5  and the first plug grounding contacts  3 A,  3 B are arranged alongside on the first side  20  of the insulation housing bracket  2 , and the second signal contact set  8  and the second plug grounding contacts  6 A,  6 B are arranged alongside on the second side  21  of the insulation housing bracket  2 . Furthermore, in this embodiment, the electrical plug connector  3000  is a Universal Serial Bus Type-C (USB Type-C) electrical plug connector. The first differential signal contacts (RX 2 +, RX 2 −), the third differential signal contacts (TX 1 −, TX 1 +), the fourth differential signal contacts (TX 2 +, TX 2 −), and the fifth differential signal contacts (RX 1 −, RX 1 +) are able to perform signal transmission satisfying specification of USB 3.0 or USB 3.1. The second differential signal contacts (D−, D+) is able to perform signal transmission satisfying specification of USB 2.0. 
     It should be noticed that, in this embodiment, the arrangement and the pin assignment of the first plug grounding contacts  3 A,  3 B as well as the first differential signal contacts (RX 2 +, RX 2 −) and the third differential signal contacts (TX 1 −, TX 1 +) of the first signal contact set  5  is identical to the arrangement and the pin assignment of the second plug grounding contacts  6 A,  6 B as well as the fourth differential signal contacts (TX 2 +, TX 2 −) and the fifth differential signal contacts (RX 1 −, RX 1 +) of the second signal contact set  8  after rotation of 180 degrees along the front-back direction of the electrical plug connector  3000 . In other words, each of the first signal contact set  5  and the second signal contact set  8  includes at least two pairs of differential signal contact sets. The at least two pairs of the differential signal contact sets of the first signal contact set  5  is symmetric to the at least two pairs of the differential signal contact sets of the second signal contact set  8  by rotation of 180 degrees along the front-back direction of the electrical plug connector. Additionally, the first differential signal contacts (RX 2 +, RX 2 −) can be compatible and communicated with the fifth differential signal contact sets (RX 1 +, RX 1 −), and the third differential signal contacts (TX 1 +, TX 1 −) can be compatible and communicated with the fourth differential signal contacts (TX 2 +, TX 2 −). 
     Therefore, no matter when the electrical plug connector  3000  is mated with the electrical receptacle connector  4000  with normal orientation (i.e., 0 degree) or when the electrical plug connector  3000  is mated with the electrical receptacle connector  4000  with reverse orientation (i.e., 180 degrees), the electrical plug connector  3000  is able to normally transmit signals with the corresponding electrical receptacle connector  4000 . Furthermore, it should be noted that each of the first grounding member  4  and the second grounding member  7  can be respectively an Electro Magnetic Interference (EMI) shielding spring members of the USB Type-C electrical plug connector. The shielding member B can be a shielding plate of the USB Type-C electrical plug connector. The EMI shielding spring members (i.e., the first grounding member  4  and the second grounding member  7 ) are disposed outside of the top side and the bottom side of the insulation housing bracket  2  of the USB Type-C electrical plug connector (i.e., the electrical plug connector  3000 ). The shielding plate (i.e., the shielding member B) is held inside the insulation housing bracket  2  of the USB Type-C electrical plug connector and located between signal contact sets (i.e., the first signal contact set  5  and the second signal contact set  8 ), so as to reduce electromagnetic interferences between a upper signal contact set and a lower signal contact set (i.e., the first signal contact set  5  and the second signal contact set  8 ) during high frequency transmission or high speed transmission. 
     When the USB Type-C electrical plug connector (i.e., the electrical plug connector  3000 ) transmits high frequency signals, the EMI shielding spring members (i.e., the first grounding member  4  and the second grounding member  7 ) shield the signal contact sets (i.e., the first signal contact set  5  and the second signal contact set  8 ) and the plug metal shell  1  of the USB Type-C electrical plug connector, and the shielding plate (i.e., the shielding member B) shields the signal contact sets of the USB Type-C electrical plug connector for preventing interferences between the signal contact sets of the USB Type-C electrical plug connector. In such a way, the EMI shielding spring members and the shielding plate reduce electromagnetic noises and electromagnetic interferences of the USB Type-C electrical plug connector during high frequency transmission, which improves performance of high frequency transmission between the USB Type-C electrical plug connector and the electrical receptacle connector and ensures normal operation of an electronic component (e.g., a wireless mouse, a Bluetooth device, or a hard disc) coupled to the USB Type-C electrical plug connector and an electronic component coupled to the USB Type-C electrical receptacle connector. 
     In this embodiment, the first connecting structures  4 A,  4 B are disposed on the first grounding member  4 , and the second connecting structures  7 A,  7 B are disposed on the second grounding member  7 . The shielding member B includes a shielding body B 1 , a resilient hook B 2 , and a grounding portion B 3 . The resilient hook B 2  extends from the shielding body B 1  for hooking the electrical receptacle connector  4000 , as shown in  FIG. 7 . The grounding portion B 3  extends from a side of the resilient hook B 2  opposite to the resilient hook for coupling to a circuit board C, as shown in  FIG. 5 . Specifically, the first insulator  22  includes two first protruding pillars  221  and two first engaging holes  222  formed on the first insulator  22 . The second insulator  23  includes two second protruding pillars  231  and two second engaging holes  232  formed on the second insulator  23 . Two first through holes B 4  and two second though holes B 5  are formed on the shielding member B. The first protruding pillar  221  engages with the second engaging hole  232  via the first through hole B 4 , and the second protruding pillar  231  engages with the first engaging hole  222  via the second through hole B 5 . Accordingly, the second insulator  23  can be assembled on the first insulator  22  and clamp the shielding member B cooperatively with the first insulator  22 . The numbers and the configurations of the first protruding pillar  221 , the first engaging hole  222 , the second protruding pillar  231 , the second engaging hole  232 , the first through hole B 4  and the second through hole B 5  are not limited to those illustrated in figures in this embodiment. In such a manner, when the electrical plug connector  3000  is mated with the electrical receptacle connector  4000 , the resilient hook B 2  of the shielding member B resiliently abuts against the electrical receptacle connector  4000 , such that a shield is formed between the signal contact sets of the electrical plug connector  3000  and the electrical receptacle connector  4000 , which prevents electromagnetic interferences and crosstalk. 
     Please refer to  FIG. 8  and  FIG. 9 .  FIG. 8  is an exploded diagram of the electrical plug connector  3000 ′ according to a second embodiment of the present invention.  FIG. 9  is a sectional diagram of the electrical plug connector  3000 ′ according to the second embodiment of the present invention. The main difference between the electrical plug connector  3000 ′ and the aforesaid electrical plug connector  3000  is that two first connecting structures  5 A′,  5 B′ and two second connecting structures  8 A′,  8 B′ of the electrical plug connector  3000 ′ are contact bending structures. The first connecting structures  5 A′,  5 B′ are disposed on two first plug grounding contacts  3 A′,  3 B′ of the electrical plug connector  3000 ′ and integrally formed with the first plug grounding contacts  3 A′,  3 B′. The second connecting structures  8 A′,  8 B′ are disposed on two second plug grounding contacts  6 A %  6 B′ and integrally formed with the second plug grounding contacts  6 A %  6 B′. Components with denoted in this embodiment identical to those in the aforesaid embodiment have identical structures and functions, and further description is omitted herein for simplicity. 
     Please refer to  FIG. 10  and  FIG. 11 .  FIG. 10  is an exploded diagram of the electrical plug connector  3000 ″ according to a third embodiment of the present invention.  FIG. 11  is a sectional diagram of the electrical plug connector  3000 ″ according to the third embodiment of the present invention. The main difference between the electrical plug connector  3000 ″ and the aforesaid electrical plug connector  3000  is that two first connecting structures  4 A″,  4 B″ and two second connecting structures  7 A″,  7 B″ of the electrical plug connector  3000 ′ are spring arms. The first connecting structures  4 A″,  4 B″ are disposed on a first grounding member  4 ″ of the electrical plug connector  3000 ″ and integrally formed with the first grounding member  4 ″. The second connecting structures  7 A″,  7 B″ are disposed on a second grounding member  7 ″ of the electrical plug connector  3000 ″ and integrally formed with the second grounding member  7 ″. Components with denoted in this embodiment identical to those in the aforesaid embodiment have identical structures and functions, and further description is omitted herein for simplicity. 
     In contrast to the prior art, the present invention utilizes the first connecting structure and the first abutting portion for electrically connecting the plug metal shell, the first grounding member and the first plug grounding contact. The present invention further utilizes the second connecting structure and second abutting portion for electrically connecting the plug metal shell, the second grounding member, and the second plug grounding contact. In such a way, electromagnetic noises and electromagnetic interferences can be reduced when the electrical plug connector transmits high frequency signals or high speed signals, such that performance of high frequency transmission or high speed transmission of the electrical plug connector is improved. Furthermore, the present invention further utilizes the shielding member disposed between the first signal contact set and the second signal contact set for shielding the first signal contact set and the second signal contact set and for preventing interferences and crosstalk therebetween. 
     Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.