Patent Publication Number: US-2022231443-A1

Title: Electrical connector set

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims benefit of priority to International Patent Application No. PCT/JP2020/037643, filed Oct. 2, 2020, and to Japanese Patent Application No. 2019-187604, filed Oct. 11, 2019, the entire contents of each are incorporated herein by reference. 
    
    
     BACKGROUND 
     Technical Field 
     The present disclosure relates to an electrical connector set. 
     Background Art 
     An electrical connector set configured by fitting a first connector and a second connector is known, as described, for example, in Japanese Unexamined Patent Application Publication No. 2018-116925. 
     The first connector in Japanese Unexamined Patent Application Publication No. 2018-116925 includes a plurality of first internal terminals and an insulating housing that holds the plurality of first internal terminals. Each of the first internal terminals is connected to an electrode of a circuit board by soldering. 
     Similarly, the second connector includes a plurality of second internal terminals and an insulating housing that holds the plurality of second internal terminals. Each of the second internal terminals is connected to an electrode of a circuit board by soldering. 
     SUMMARY 
     There is a need to further improve the electrical characteristics of an electrical connector set. 
     Thus, the present disclosure provides an electrical connector set with improved electrical characteristics. 
     Accordingly, an electrical connector set according to the present disclosure includes a first substrate having a first conductor, and a first internal terminal having a first mounting portion and a second mounting portion that are mounted on the first conductor of the first substrate and a projecting portion extending in a curved shape between the first mounting portion and the second mounting portion. The electrical connector set further includes a second substrate having a second conductor, and a second internal terminal having a third mounting portion that is mounted on the second conductor of the second substrate and a recessed portion forming the third mounting portion at a bottom portion, in which the projecting portion of the first internal terminal and the recessed portion of the second internal terminal are configured to be fitted to each other. 
     According to the present disclosure, an electrical connector set with improved electrical characteristics can be provided. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a perspective view of an upper surface side of a first connector according to an embodiment; 
         FIG. 1B  is a perspective view of a lower surface side of the first connector according to the embodiment; 
         FIG. 1C  is an exploded perspective view of the first connector according to the embodiment; 
         FIG. 1D  is a schematic plan view of a first substrate according to the embodiment; 
         FIG. 2A  is a perspective view of an upper surface side of a second connector according to the embodiment; 
         FIG. 2B  is a perspective view of a lower surface side of the second connector according to the embodiment; 
         FIG. 2C  is an exploded perspective view of the second connector according to the embodiment; 
         FIG. 2D  is a schematic plan view of a second substrate according to the embodiment; 
         FIG. 3A  is a perspective view of an electrical connector set according to the embodiment as viewed from the first connector side; 
         FIG. 3B  is a perspective view of the electrical connector set according to the embodiment as viewed from the second connector side; 
         FIG. 4A  is a perspective view of a first internal terminal according to the embodiment as viewed from bellow; 
         FIG. 4B  is a perspective view of the first internal terminal according to the embodiment as viewed from above; 
         FIG. 5A  is a perspective view of a second internal terminal according to the embodiment as viewed from below; 
         FIG. 5B  is a perspective view of the second internal terminal according to the embodiment as viewed from above; 
         FIG. 6A  is a schematic plan view of a second insulator and the second internal terminals according to the embodiment; 
         FIG. 6B  is a partially enlarged view of  FIG. 6A ; 
         FIG. 7A  is a schematic side view illustrating the first internal terminal and first and second mounting members according to a variation; and 
         FIG. 7B  is a schematic side view illustrating the second internal terminal and third and fourth mounting members according to the variation. 
     
    
    
     DETAILED DESCRIPTION 
     According to a first aspect of the present disclosure, there is provided an electrical connector set including a first substrate having a first conductor, and a first internal terminal having a first mounting portion and a second mounting portion that are mounted on the first conductor of the first substrate and a projecting portion extending in a curved shape between the first mounting portion and the second mounting portion. The electrical connector set further includes a second substrate having a second conductor, a second internal terminal having a third mounting portion that is mounted on the second conductor of the second substrate and a recessed portion forming the third mounting portion at a bottom portion, in which the projecting portion of the first internal terminal and the recessed portion of the second internal terminal are configured to be fitted to each other. 
     According to such a configuration, since the first internal terminal has two mounting portions, it is possible to disperse the electricity flowing through the first internal terminal compared to a case in which the first internal terminal has only one mounting portion. Thus, when the internal terminals are connected to a power supply, the current is dispersed instead of concentrated, thereby suppressing heat generation due to overcurrent. Further, when the internal terminals are connected to the ground, the potential changes of the internal terminals as the ground terminals can be suppressed, improving the shielding properties. In this way, the electrical characteristics of the electrical connector set can be improved. 
     According to a second aspect of the present disclosure, there is provided the electrical connector set according to the first aspect, in which the second internal terminal has a first portion rising from the bottom portion of the recessed portion on one side and a second portion rising from the bottom portion on another side, and the first portion is a portion having a free end. According to such a configuration, the degree of freedom in design is improved by making the first portion the portion having a free end. 
     According to a third aspect of the present disclosure, there is provided the electrical connector set according to the second aspect, further including a fourth mounting portion with which the second internal terminal is mounted on the second conductor of the second substrate separately from the third mounting portion, in which the second internal terminal further has a projecting portion to be connected to the second portion and a third portion extending from the projecting portion to the fourth mounting portion. According to such a configuration, since the second internal terminal has two mounting portions, the electricity flowing through the second internal terminal can be dispersed similarly to the first internal terminal, thereby improving the electrical characteristics of the electrical connector set. 
     According to a fourth aspect of the present disclosure, there is provided the electrical connector set according to the third aspect, further including an insulator holding the second internal terminal, in which the third portion of the second internal terminal has a wide portion with a large width, and the insulator has a first notch that is recessed to accommodate the wide portion of the third portion. According to such a configuration, by providing the first notch in the insulator to accommodate the wide portion of the second internal terminal, the second internal terminal can be fixed to the insulator. 
     According to a fifth aspect of the present disclosure, there is provided the electrical connector set according to the fourth aspect, in which the insulator further has a second notch that is recessed outward for the projecting portion of the second internal terminal. According to such a configuration, by providing the second notch in the insulator, it is possible to secure a space in which the projecting portion of the second internal terminal is pushed outward and deformed when the first internal terminal and the second internal terminal are fitted to each other. 
     According to a sixth aspect of the present disclosure, there is provided the electrical connector set according to any one of the second to fifth aspects, in which a width of the first portion of the second internal terminal is larger than a width of the second portion of the second internal terminal. According to such a configuration, by making the width of the first portion, which is the portion having a free end, larger than the width of the second portion, the spring constant of the portion having a free end can be increased, so that the value of the spring constant of the portion having a free end can be brought closer to the values of the spring constants of the second portion and the projecting portion connected to the second portion. This makes it easier to secure contact points with the first internal terminal. 
     According to a seventh aspect of the present disclosure, there is provided the electrical connector set according to any one of the first to sixth aspects, in which the first and second conductors are conductors that are connected to a power supply. According to such a configuration, when the internal terminals are connected to the power supply, since the first internal terminal has two mounting portions, it is possible to disperse the electricity flowing through the internal terminals and suppress heat generation due to overcurrent compared to a case in which the first internal terminal has only one mounting portion. 
     According to an eighth aspect of the present disclosure, there is provided the electrical connector set according to any one of the first to sixth aspects, in which the first and second conductors are conductors that are connected to the ground. According to such a configuration, when the internal terminals are connected to the ground, since the first internal terminal includes two mounting portions, the electricity flowing through the internal terminals can be dispersed and the potential changes as the ground terminals can be suppressed compared to a case in which the first internal terminal has only one mounting portion, thereby improving the shielding properties. 
     Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the drawings. 
     Embodiment 
       FIGS. 1A to 1C  are diagrams illustrating a first connector  2  according to the embodiment.  FIGS. 2A to 2C  are diagrams illustrating a second connector  4  according to the embodiment.  FIGS. 3A and 3B  are perspective views illustrating an electrical connector set  6 . 
     By fitting the first connector  2  illustrated in  FIGS. 1A to 1C  and the second connector  4  illustrated in  FIGS. 2A to 2C  to each other, the electrical connector set  6  illustrated in FIGS.  3 A and  3 B is configured. In the embodiment, the first connector  2  is a male multi-pole connector, and the second connector  4  is a female multi-pole connector. 
     The first connector  2  will be described with reference to  FIGS. 1A to 1D .  FIG. 1A  is a perspective view of an upper surface side of the first connector  2 ,  FIG. 1B  is a perspective view of a lower surface side of the first connector  2 , and  FIG. 1C  is an exploded perspective view of the first connector  2 .  FIG. 1D  is a schematic plan view illustrating a first substrate  7  on which the first connector  2  is mounted. 
     In  FIGS. 1A to 1D , a length direction (longer direction) of the first connector  2  is defined as an X direction, a width direction (shorter direction) thereof is defined as a Y direction, and a height direction (up-down direction) thereof orthogonal to the longer direction and the shorter direction thereof is defined as a Z direction. 
     As illustrated in  FIGS. 1A to 1C , the first connector  2  includes a plurality of first internal terminals  8 , a first external terminal  10 , and a first insulator  12 . 
     The plurality of first internal terminals  8  are mounted on the first substrate  7  illustrated in  FIG. 1D . As illustrated in  FIG. 1D , the first substrate  7  has a plurality of first conductors  50 . The first conductors  50  are provided in a one-to-one correspondence with the first internal terminals  8 , and one first internal terminal  8  is mounted on one first conductor  50 . In the embodiment, a resist  51  is provided on a surface of a central portion of the first conductor  50 , and the first conductor  50  is divided into two portions. One first internal terminal  8  is mounted on one first conductor  50  at the two portions. This allows the electricity flowing through the first internal terminal  8  to be dispersed compared to a case in which one first internal terminal  8  is mounted on the first conductor  50  at only one portion. Details will be described later. Note that in  FIGS. 1A, 1B, and 1C , the first substrate  7  is not illustrated. 
     The first internal terminal  8  is a terminal that is fitted into and electrically connected to a second internal terminal  26  (see  FIGS. 2A to 2C ) of the second connector  4  described later. The first internal terminals  8  are each made of the same conductive material (e.g., phosphor bronze). Due to the presence of the plurality of first internal terminals  8 , the first connector  2  illustrated in  FIGS. 1A to 1C  is referred to as a “multi-pole” connector. 
     The plurality of first internal terminals  8  are arranged so as to be spaced apart from each other along the X direction. In the embodiment, two rows of the first internal terminals  8  extending in the X direction are spaced apart in the Y direction. 
     As illustrated in  FIG. 1C  and the like, the first internal terminal  8  is configured as a male terminal. The male terminal has a projecting portion  40  and is fitted into a recessed portion  42  (see  FIG. 2C ) of the second internal terminal  26  at the projecting portion  40 . 
     The first external terminal  10  is a terminal that is fitted into and electrically connected to a second external terminal  28  (see  FIGS. 2A to 2C ) of the second connector  4  described later. The first external terminal  10  functions as a ground terminal. The first external terminal  10  is made of the same conductive material (e.g., phosphor bronze) as the first internal terminal  8  described above. 
     The first external terminal  10  is configured as a male terminal and is fitted into the second external terminal  28 , which is a female terminal. Since the first external terminal  10  is a male type, the first connector  2  illustrated in  FIGS. 1A to 1C  is referred to as a “male type” connector. 
     The first external terminal  10  according to the embodiment includes a first portion  10 A and a second portion  10 B spaced apart from each other in the X direction. The first portion  10 A and the second portion  10 B are provided so as to sandwich the plurality of first internal terminals  8  in the X direction. Not limited to such a configuration, the first portion  10 A and the second portion  10 B may be configured as an integral part. 
     The first insulator  12  illustrated in  FIGS. 1A to 1C  is a member that holds the plurality of first internal terminals  8  and the first external terminal  10  in a state of being electrically insulated from each other. The first insulator  12  is made of, for example, a resin (e.g., a liquid crystal polymer), which is an insulating material. 
     Next, the second connector  4  will be described with reference to  FIGS. 2A to 2D .  FIG. 2A  is a perspective view of an upper surface side of the second connector  4 ,  FIG. 2B  is a perspective view of a lower surface side of the second connector  4 , and  FIG. 2C  is an exploded perspective view of the second connector  4 .  FIG. 2D  is a schematic plan view illustrating a second substrate  25  on which the second connector  4  is mounted. 
     In  FIGS. 2A to 2D , similarly to the first connector  2  described above, a length direction (longer direction) of the second connector  4  is defined as the X direction, a width direction (shorter direction) thereof is defined as the Y direction, and a height direction (up-down direction) thereof is defined as the Z direction. 
     As illustrated in  FIGS. 2A to 2C , the second connector  4  includes a plurality of second internal terminals  26 , the second external terminal  28 , and a second insulator  30 . 
     The plurality of second internal terminals  26  are mounted on the second substrate  25  illustrated in  FIG. 2D . As illustrated in  FIG. 2D , the second substrate  25  has a plurality of second conductors  60 . The second conductors  60  are provided in a one-to-one correspondence with the second internal terminals  26 , and one second internal terminal  26  is mounted on one second conductor  60 . In the embodiment, a resist  61  is provided on a surface of a central portion of the second conductor  60 , and the second conductor  60  is divided into two portions. One second internal terminal  26  is mounted on one second conductor  60  at the two portions. This allows the electricity flowing through the second internal terminal  26  to be dispersed compared to a case in which one second internal terminal  26  is mounted on the second conductor  60  at only one portion. Details will be described later. Note that in  FIGS. 2A, 2B, and 2C , the second substrate  25  is not illustrated. 
     The second internal terminal  26  is a terminal that is fitted to and electrically connected to the first internal terminal  8  of the first connector  2  illustrated in  FIGS. 1A to 1C . The second internal terminals  26  are each made of the same conductive material (e.g., phosphor bronze). Due to the presence of the plurality of second internal terminals  26 , the connector illustrated in  FIGS. 2A to 2C  is referred to as a “multi-pole” connector. 
     The plurality of second internal terminals  26  are arranged so as to be spaced apart from each other along the X direction. In the embodiment, two rows of the second internal terminals  26  extending in the X direction are spaced apart in the Y direction. 
     As illustrated in  FIG. 2C  and the like, the second internal terminal  26  is configured as a female terminal. The female terminal has the recessed portion  42 , and is fitted to the projecting portion  40  (see  FIG. 1C ) of the first internal terminal  8  at the recessed portion  42 . 
     The second external terminal  28  is a terminal that is fitted to and electrically connected to the first external terminal  10  of the first connector  2  illustrated in  FIGS. 1A to 1C . The second external terminal  28  functions as a ground terminal. The second external terminal  28  is made of the same conductive material (e.g., phosphor bronze) as the second internal terminal  26  described above. 
     The second external terminal  28  is configured as a female terminal and has a function of guiding the first external terminal  10 , which is a male terminal, inward. As illustrated in  FIG. 2C , the second external terminal  28  includes a guide portion  21 , which is an inclined surface for guiding the first external terminal  10 . Since the second external terminal  28  is a female type, the second connector  4  illustrated in  FIGS. 2A to 2C  is referred to as a “female type” connector. 
     The second external terminal  28  has a shape that surrounds the plurality of second internal terminals  26 . By surrounding the second internal terminals  26  with the second external terminal  28 , it is possible to suppress generation of noise due to the second internal terminals  26  and the first internal terminals  8 . 
     In the embodiment, the second external terminal  28  is configured as a single annular member. Not limited to such a shape, the second external terminal  28  may be constituted of a plurality of separate members. 
     The second external terminal  28  further includes a locking portion  19 . The locking portion  19  is a projection that functions as a stopper for the first external terminal  10  when the first external terminal  10  is fitted into the second external terminal  28 . When the first external terminal  10  and the second external terminal  28  are fitted to each other, the locking portion  19  does not necessarily have to be in contact with the first external terminal  10 . 
     The second insulator  30  illustrated in  FIGS. 2A to 2C  is a member that holds the second internal terminals  26  and the second external terminal  28  described above in a state of being electrically insulated from each other. The second insulator  30  is made of, for example, a resin (e.g., a liquid crystal polymer), which is an insulating material. 
     The electrical connector set  6  illustrated in  FIGS. 3A and 3B  is configured by fitting the male first connector  2  described above into the female second connector  4  described above.  FIG. 3A  is a perspective view of the electrical connector set  6  as viewed from the first connector  2  side, and  FIG. 3B  is a perspective view of the electrical connector set  6  as viewed from the second connector  4  side. 
     When fitting the first connector  2  into the second connector  4 , the first external terminal  10  (male type) of the first connector  2  is fitted into the second external terminal  28  (female type) of the second connector  4 . Then, the projecting portion  40  (male type) of the first internal terminal  8  of the first connector  2  is fitted into the recessed portion  42  (female type) of the second internal terminal  26  of the second connector  4 . However, the order of fitting can be changed as appropriate. 
     In the electrical connector set  6  having the above-described configuration, the mounting structure for mounting the first internal terminal  8  of the first connector  2  on the first substrate  7  and the mounting structure for mounting the second internal terminal  26  of the second connector  4  on the second substrate  25  will be described with reference to  FIGS. 4A, 4B, 5A, and 5B . 
       FIG. 4A  is a perspective view of the first internal terminal  8  as viewed from below, and  FIG. 4B  is a perspective view of the first internal terminal  8  as viewed from above. 
     As illustrated in  FIGS. 4A and 4B , the first internal terminal  8  is provided with a first mounting portion  52  and a second mounting portion  54 . The first mounting portion  52  is one end portion of the first internal terminal  8 , and the second mounting portion  54  is another end portion of the first internal terminal  8 . The first mounting portion  52  is mounted on the first conductor  50  of the first substrate  7  with a first mounting member  52 A interposed therebetween, and the second mounting portion  54  is mounted on the first conductor  50  with a second mounting member  54 A interposed therebetween. Both the first mounting member  52 A and the second mounting member  54 A are members for mounting the first internal terminal  8  on the first conductor  50 . In the embodiment, the first mounting member  52 A and the second mounting member  54 A are made of solder. In  FIGS. 4A and 4B , the first mounting member  52 A and the second mounting member  54 A are schematically illustrated, and are actually spread out after being melted. 
     As illustrated in  FIGS. 4A and 4B , the first internal terminal  8  has the projecting portion  40 . Both ends of the projecting portion  40  are bent to form the first mounting portion  52  and the second mounting portion  54 . The first mounting member  52 A and the second mounting member  54 A are in contact with bottom surfaces of the first mounting portion  52  and the second mounting portion  54 , respectively. 
     By providing the two mounting portions  52  and  54  for mounting the first internal terminal  8  on the first conductor  50 , it is possible to disperse the electricity flowing through the first internal terminal  8  compared to a case in which only one mounting portion is provided. 
     When the electrical connector set  6  is in use, the first conductor  50  is connected to either a power supply, the ground, or a signal line. When the first conductor  50  is connected to the power supply, heat generation due to overcurrent at the first internal terminal  8  can be suppressed by dispersing the electricity flowing through the first internal terminal  8 . In addition, when the first conductor  50  is connected to the ground, it is possible to suppress the potential change of the first internal terminal  8  by dispersing the electricity flowing through the first internal terminal  8 , thereby improving the shielding properties of the first internal terminal  8  as a ground terminal. In this way, the electrical characteristics of the electrical connector set  6  can be improved. 
     When only one mounting portion is provided in the first internal terminal  8 , due to the characteristics of conductor resistance, the current density is concentrated in the shortest path, which makes it easy to generate heat, so there is a possibility that the electric connector set  6  cannot be used for applications in which a large current flows, such as a power supply. On the other hand, in the first internal terminal  8  of the embodiment, heat generation is suppressed by providing the two mounting portions  52  and  54 . Thus, the electric connector set  6  can also be used for large current applications. In this way, the electric connector set  6  can be used for both large current applications and high frequency applications. In addition, since a large current can be applied without increasing the width of the first internal terminal  8 , the dimension of the first connector  2  in the longer direction X can be reduced, and the number of members can be reduced, thereby reducing costs. 
       FIG. 5A  is a perspective view of the second internal terminal  26  as viewed from below, and  FIG. 5B  is a perspective view of the second internal terminal  26  as viewed from above. 
     As illustrated in  FIGS. 5A and 5B , the second internal terminal  26  is provided with a third mounting portion  56  and a fourth mounting portion  58 . The third mounting portion  56  is mounted on the second conductor  60  of the second substrate  25  with a third mounting member  56 A interposed therebetween, and the fourth mounting portion  58  is mounted on the second conductor  60  with a fourth mounting member  58 A interposed therebetween. Both the third mounting member  56 A and the fourth mounting member  58 A are members for mounting the second internal terminal  26  on the second conductor  60 . In the embodiment, the third mounting member  56 A and the fourth mounting member  58 A are made of solder. In  FIGS. 5A and 5B , the third mounting member  56 A and the fourth mounting member  58 A are schematically illustrated similarly to  FIGS. 4A and 4B . 
     As illustrated in  FIGS. 5A and 5B , the second internal terminal  26  further has a bottom portion  26 A, a first portion  26 B, a second portion  26 C, a projecting portion  26 D, and a third portion  26 E. 
     The bottom portion  26 A, the first portion  26 B, and the second portion  26 C are portions constituting the recessed portion  42  of the second internal terminal  26 . The bottom portion  26 A is a bottom surface of the recessed portion  42  and constitutes the third mounting portion  56 . The third mounting member  56 A is in contact with a bottom surface of the third mounting portion  56 . The first portion  26 B is a portion rising from the bottom portion  26 A on one side, and the second portion  26 C is a portion rising from the bottom portion  26 A on another side. A tip end of the first portion  26 B is not connected to any other member and is a free end, and the first portion  26 B is a portion having a free end. In other words, one end of the first portion  26 B is not connected to any other member, and another end thereof is connected to the bottom portion  26 A, which is a portion to be mounted on the second conductor  60  of the second substrate  25 . The second portion  26 C is not a portion having a free end, but is connected to the bottom portion  26 A and the projecting portion  26 D. 
     The projecting portion  26 D is a portion that projects in a direction opposite to the direction in which the recessed portion  42  is recessed, that is, upward. The projecting portion  26 D has a smoothly curved shape and is connected to the third portion  26 E. The third portion  26 E extends from the projecting portion  26 D to the fourth mounting portion  58 . The fourth mounting member  58 A is in contact with a bottom surface of the fourth mounting portion  58 . 
     Thus, by providing the two mounting portions  56  and  58  for mounting the second internal terminal  26  on the second conductor  60 , the same effect as that of the first internal terminal  8  can be achieved, thereby improving the electrical characteristics of the electrical connector set  6 . 
     As described above, according to the electrical connector set  6  of the embodiment, the first internal terminal  8  has the first mounting portion  52  and the second mounting portion  54  that are mounted on the first conductor  50  of the first substrate  7 , and the second internal terminal  26  has the third mounting portion  56  that is mounted on the second conductor  60  of the second substrate  25 . According to such a configuration, since the first internal terminal  8  has the two mounting portions  52  and  54 , it is possible to disperse the electricity flowing through the first internal terminal  8  compared to a case in which the first internal terminal  8  has only one mounting portion. In this embodiment, the second internal terminal  26  also has the two mounting portions  56  and  58 . However, by providing the two mounting portions  52  and  54  in the first internal terminal  8 , an effect of dispersing the electricity flowing through the electrical connector set  6  can be achieved regardless of the number of mounting portions of the second internal terminal  26 , for example, even when only the third mounting portion  56  is provided. 
     Here, in the second internal terminal  26  of the embodiment, the width is locally changed. To be specific, the bottom portion  26 A, the second portion  26 C, and the projecting portion  26 D have uniformly the same width, whereas the first portion  26 B and the third portion  26 E have wide portions  70  and  72  that are locally increased in width, respectively. 
     The wide portion  70  of the first portion  26 B is provided to increase the spring constant of the first portion  26 B. Since one side of the first portion  26 B is a free end, the first portion  26 B tends to have a smaller spring constant and be softer than the portions in which both sides are fixed to the third mounting portion  56  and the fourth mounting portion  58 , such as the second portion  26 C and the projecting portion  26 D. On the other hand, the projecting portion  26 D is less deformable and has a higher spring constant than the portion having a free end. Thus, when the second internal terminal  26  is fitted to the first internal terminal  8 , the contact pressure tends to be weaker on the first portion  26 B, which is the portion having a free end. At this time, when the width of the entire second internal terminal  26  is increased in order to increase the spring constant, the projecting portion  26 D becomes less deformable, making it difficult to fit the second internal terminal  26  to the first internal terminal  8 . Thus, the spring constant of the second internal terminal  26  is locally increased by providing the wide portion  70  in the first portion  26 B while keeping the width of the second portion  26 C and the projecting portion  26 D the same as the width of the bottom portion  26 A. This allows the spring constant of the first portion  26 B to be brought closer to the spring constants of the second portion  26 C and the projecting portion  26 D, so that all the portions have an equivalent elastic force. According to such a configuration, when the projecting portion  40  of the first internal terminal  8  is fitted into the recessed portion  42  of the second internal terminal  26 , forces can be evenly applied to the projecting portion  40  of the first internal terminal  8  so as to sandwich the projecting portion  40  from both sides in the Y direction. As a result, accurate fitting can be achieved. In this way, by selectively increasing the thickness of the first portion  26 B, which is the portion having a free end, to bring the spring constant closer to the spring constant of the projecting portion  26 D, appropriate fitting can be achieved while maintaining the contact pressure. 
     As described above, by making the width of the first portion  26 B, which is the portion having a free end, larger than the width of the second portion  26 C, the value of the spring constant of the first portion  26 B can be brought closer to the values of the spring constants of the second portion  26 C and the projecting portion  26 D. When setting the widths of the first portion  26 B and the second portion  26 C, the average width or the maximum width of the first portion  26 B should be set to be larger than the average width or the maximum width of the second portion  26 C. 
     On the other hand, the wide portion  72  of the third portion  26 E is provided for fixing the second internal terminal  26  to the second insulator  30  described above. This will be described in detail with reference to  FIGS. 6A and 6B . 
       FIG. 6A  is a plan view of the second insulator  30  and the second internal terminals  26 . For the sake of convenience,  FIG. 6A  illustrates a state in which some of the second internal terminals  26  are removed.  FIG. 6B  is a partially enlarged view of  FIG. 6A . 
     As illustrated in  FIG. 6A , the second insulator  30  is provided with openings  74  for arranging the plurality of second internal terminals  26 . 
     Each of the openings  74  has a first notch  76  and a second notch  78  as illustrated in  FIG. 6B . 
     The first notch  76  is a notch for arranging the wide portion  72  of the second internal terminal  26  described above. The first notch  76  is provided for the second internal terminal  26  as a recessed portion that is recessed outward in the X direction, which is the length direction of the second connector  4 . By arranging the wide portion  72  in the first notch  76 , the movement of the second internal terminal  26  in the opening  74  in the Y direction can be restricted, so that the second internal terminal  26  can be fixed to the second insulator  30 . 
     The second notch  78  is a notch for receiving the projecting portion  26 D of the second internal terminal  26 . The second notch  78  is provided for the projecting portion  26 D of the second internal terminal  26  as a recessed portion that is recessed outward in the Y direction, which is the width direction of the second connector  4 . By providing the second notch  78 , it is possible to secure a space in which the projecting portion  26 D of the second internal terminal  26  is deformed when the first internal terminal  8  is fitted into the second internal terminal  26  and the projecting portion  26 D of the second internal terminal  26  is pushed outward. This allows the second internal terminal  26  to exert a desired elastic force, so that accurate fitting can be achieved. 
     (Variation) 
     A variation for the mounting members  52 A and MA of the first internal terminal  8  and the mounting members  56 A and  58 A of the second internal terminal  26  will be described with reference to  FIGS. 7A and 7B . 
       FIG. 7A  is a schematic side view illustrating a first mounting member  152 A and a second mounting member  154 A of the first internal terminal  8  of the variation. 
     As illustrated in  FIG. 7A , the first mounting member  152 A and the second mounting member  154 A are set to be longer in the Y direction than the first mounting member  52 A and the second mounting member  54 A of the embodiment. 
     Assuming that two contact points of the first internal terminal  8  with the second internal terminal  26  are a first contact point  182  and a second contact point  184 , respectively, it is designed that the first contact point  182  overlaps the first mounting member  152 A in the Z direction and the second contact point  184  overlaps the second mounting member  154 A in the Z direction (see dotted lines). 
     By arranging the first mounting member  152 A and the second mounting member  154 A directly below the contact points  182  and  184 , respectively, in this manner, the paths of electricity flowing from the first internal terminal  8  to the first mounting member  152 A and the second mounting member  154 A are shortened compared to a configuration in which no mounting member is present directly below the contact points  182  and  184 . By shortening the electrical paths, heat generation can be reduced when the first internal terminal  8  is connected to a power supply, and when the first internal terminal  8  is connected to the ground terminal, the potential change of the ground terminal can be suppressed, improving the shielding properties. Such a design can improve the electrical characteristics of the electrical connector set  6 . 
       FIG. 7B  is a schematic side view illustrating a third mounting member  156 A and a fourth mounting member  158 A of the second internal terminal  26  of the variation. 
     As illustrated in  FIG. 7B , the third mounting member  156 A and the fourth mounting member  158 A are set to be longer in the Y direction than the third mounting member  56 A and the fourth mounting member  58 A of the embodiment. 
     Assuming that two contact points of the second internal terminal  26  with the first internal terminal  8  are a third contact point  186  and a fourth contact point  188 , respectively, both the third contact point  186  and the fourth contact point  188  are designed to overlap the third mounting member  156 A in the Z direction (see dotted lines). 
     By arranging the third mounting member  156 A directly below the contact points  186  and  188  in this manner, the paths of electricity flowing from the second internal terminal  26  to the third mounting member  156 A are shortened compared to a configuration in which no mounting member is present directly below the contact points  186  and  188 . By shortening the paths of electricity, the same effect as that of the first internal terminal  8  described above can be achieved, so that the electrical characteristics of the electrical connector set  6  can be improved. 
     Although the present disclosure has been described with reference to the above embodiments, the present disclosure is not limited to the above embodiments. For example, the number of internal terminals and external terminals may be any number. 
     In addition, in the embodiment, the case in which two mounting portions are provided in each of the first internal terminal  8  and the second internal terminal  26  has been described, the present disclosure is not limited to such a case. For example, two mounting portions may be provided in the first internal terminal  8 , and only one mounting portion may be provided in the second internal terminal  26 . In this case, the fourth mounting portion  58  of the second internal terminal  26  may be omitted and only the third mounting portion  56  may be provided, and only the third mounting portion  56  may be mounted on the second conductor  60  of the second substrate  25 . In this case, the resist  61  of the second substrate  25  illustrated in  FIG. 2D  may be omitted, and the second conductor  60  divided into the two portions may be integrated into one. 
     While the present disclosure has been fully described in connection with preferred embodiments thereof with reference to the accompanying drawings, various variations and modifications are obvious to those skilled in the art. It should be understood that such variations and modifications are included in the present disclosure as long as they do not depart from the scope of the present disclosure according to the appended claims. In addition, changes in the combination and order of elements in each embodiment can be achieved without departing from the scope and spirit of the present disclosure. 
     It should be noted that any of the various embodiments described above can be combined as appropriate to achieve the effects of each embodiment. 
     The present disclosure is applicable to any electrical connector set.