Patent Publication Number: US-10320124-B1

Title: Electrical connector with internal terminals having opposite sides located from connector internal sidewalls

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to an electrical connector, and especially relates to an electrical connector with tuned impedance terminals. 
     2. Description of the Prior Art 
     Electrical connectors are widely used in various electronic devices. By the electrical connectors, electronic devices or components in an electronic device can be electrically connected and transmit signals therebetween. As the frequency for transmitting signals becomes higher, the impedance of the electrical connector produces an increasing effect on the signal transmission. Under a condition of high frequency transmission, when an electrical connector is not impedance matched with a transmission line, the electrical connector will reflect signals, leading to signal decay. The higher the extent of the impedance mismatch becomes, the worse the signal decay becomes. Even the signal transmission is failed. The structure designs of current electrical connectors are usually based on the mechanical properties of the electrical connectors, e.g. insertion force, withdrawal force, and durability. For the electrical properties of the electrical connectors, the design therefor is usually done by experience. In a common structure design for an electrical connector, when the electrical connector cannot meet the impedance requirement therefor, the electrical connector needs to be modified in the structural sizes of the insulation housing and the conductive terminals thereof. It wastes time and increases the cost for making the electrical connector. 
     SUMMARY OF THE INVENTION 
     An objective of the invention is to provide an electrical connector, of which a conductive terminal has a through hole, located at a portion of the conductive terminal fixed in an insulation housing of the electrical connector, and side surfaces, kept away from inner sidewalls of the insulation housing. The structure design is conducive to an adjustment to the impedance of the electrical connector. 
     An electrical connector according to the invention includes an insulation housing and a terminal. The insulation housing has a fixing hole. The first fixing hole has a first inner sidewall and a second inner sidewall opposite to the first inner sidewall. The first terminal includes a contact portion, a fixed portion, and a connection portion. The contact portion and the connection portion extend from the fixed portion respectively and are exposed out of the insulation housing. The fixed portion has a first side surface and a second side surface opposite to the first side surface in a direction. The fixed portion has a through hole. The fixed portion is fixed in the fixing hole. The through hole is located in the fixing hole. The first side surface faces the first inner sidewall and is kept away from the first inner sidewall by a first distance. The second side surface faces the second inner sidewall and is kept away from the second inner sidewall by a second distance. Thereby, in practice, the impedance of the electrical connector can be adjusted by changing the size of the fixed portion relative to the through hole (e.g. the outlines of the fixed portion and the hole dimension of the through hole in a direction perpendicular to the direction) or changing the first distance and the second distance. 
     Another object of the invention is to provide a terminal for being used in an electrical connector. The terminal has a through hole located at a portion thereof fixed in an insulation housing of the electrical connector, which is conducive to an adjustment to the impedance of the electrical connector. 
     A terminal according to the invention includes a fixed portion, a contact portion, and a connection portion. The fixed portion has a first side surface and a second side surface opposite to the first side surface in a first direction. The fixed portion includes an abutting portion and a through hole. The abutting portion protrudes in a second direction perpendicular to the first direction. The first through hole is located at the first abutting portion and passes through the first side surface and the second side surface. Therein, the fixed portion is fixed in the electrical connector through the abutting portion. The contact portion extends from the fixed portion extend. The connection portion extends from the fixed portion. Thereby, in practice, the impedance of the electrical connector can be adjusted by changing the size of the through hole and the profile of the abutting portion. 
     Compared with the prior art, the electrical connector and the terminal according to the invention can be modified by changing the size of the fixed portion (e.g. the profile of the abutting portion, the hole dimension of the through hole and so on) or changing the first distance and the second distance, so as to adjust the impedance of the electrical connector. The structure design facilitate adjustment to the impedance of the electrical, which is conducive to reduction of cost and development time and effectively solves the problem in the prior art. 
     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 illustrating an electrical connector of an embodiment according to the invention. 
         FIG. 2  is an exploded view of the electrical connector in  FIG. 1 . 
         FIG. 3  is a sectional view of an insulation housing of the electrical connector along the line X-X in  FIG. 1 . 
         FIG. 4  is a side view of an upper row terminal of the electrical connector in  FIG. 1 . 
         FIG. 5  is a side view of a lower row terminal of the electrical connector in  FIG. 1 . 
         FIG. 6  is a sectional view of the electrical connector along the line X-X in  FIG. 1 . 
         FIG. 7  is an enlarged view of the circle A in  FIG. 6 . 
         FIG. 8  is a sectional view of the electrical connector along the line Y-Y in  FIG. 1 . 
         FIG. 9  is an exploded view of a portion of a simplified variant of the electrical connector in  FIG. 1 . 
         FIG. 10  is a sectional view of the variant along the line Z-Z in  FIG. 9  after the components thereof are assembled. 
     
    
    
     DETAILED DESCRIPTION 
     Please refer to  FIG. 1  to  FIG. 6 . An electrical connector of an embodiment according to the invention includes an insulation housing  12 , a rear cover  14 , a plurality of upper row terminals  16 , and a plurality of lower row terminals  18  (of which only several are shown in  FIG. 2  for drawing simplification). The insulation housing  12  (e.g. but not limited to a plastic injection part) has a plurality of upper row fixing holes  122  and a plurality of lower row fixing holes  124 , which are arranged in parallel and correspond to the plurality of upper row terminals  16  and the plurality of lower row terminals respectively. The upper row terminal  16  includes a contact portion  162 , a fixed portion  164 , and a connection portion  166 . The contact portion  162  and the connection portion  166  extend from the fixed portion  164  respectively. The upper row terminal is fixed in the corresponding upper row fixing hole  122  through the fixed portion  164  such that the contact portion  162  and the connection portion  166  are exposed out of the insulation housing  12 . Similarly, the lower row terminal  18  includes a contact portion  182 , a fixed portion  184 , and a connection portion  186 . The contact portion  182  and the connection portion  186  extend from the fixed portion  184  respectively. The lower row terminal  18  is fixed in the corresponding lower row fixing hole  124  through the fixed portion  184  such that the contact portion  182  and the connection portion  186  are exposed out of a front side  12   a  and a rear side  12   b  of the insulation housing  12  respectively. 
     In the embodiment, the electrical connector  1  is a female board electrical connector. The insulation housing  12  has a front side  12   a  and a rear side  12   b . The insulation housing  12  has a socket  126  at the front side  12   a . The upper row fixing holes  122  and the lower row fixing holes  124  passes through the insulation housing  12  to connect the front side  12   a  and the rear side  12   b , so that the contact portions  162  of the upper row terminals  16  and the contact portions  182  of the lower row terminals  18  are exposed in the socket  126  (i.e. exposed out of the insulation housing  12  at the front side  12   a ). In an application, a mating male electrical connector  3  (shown in dashed lines in  FIG. 6 ) can be inserted into the socket  126  (the insertion direction therefor being indicated by an arrow in  FIG. 6 ) such that conductive terminals  32  of the electrical connector electrically contact the conductive upper row and lower row terminals  16  and  18 , which achieves connection of the electrical connectors  1  and  3  (including mechanical connection and electrical connection). Therein, the male electrical connector  3  can be a board electrical connector, a cable connector, or even an adapter. Furthermore, in the embodiment, the connection portion  166  of the upper row terminal  16  and the connection portion  186  of the lower row terminal  18  are exposed out of the insulation housing  12  at the rear side  12   b  and bend downward to be capable of being fixed to a circuit board  4  (shown by dashed lines in  FIG. 6 ) through but not limited to through-hole technology (e.g. surface-mount technology). Therein, the insulation housing  12  has two locating posts  128  at its bottom which protrude downward. The locating posts  128  can be inserted into locating holes of the circuit board  4  (not shown in  FIG. 6 ). The electrical connector  1  also includes a plurality of fixing parts  20  (e.g. made of metal) which are connected to the insulation housing  12  and extend downward to be capable of being inserted into fixing holes of the circuit board  4  (not shown in  FIG. 6 ) and fixed (e.g. by soldering). The fixing parts  20  perform locating and fixing effects. 
     In the embodiment, the upper row terminal  16  and the lower row terminal  18  are structurally similar; the upper row fixing hole  122  and the lower row fixing hole  124  are also structurally similar. Therefore, the following descriptions are based on the upper row terminal  16  and the upper row fixing hole  122 . For descriptions about the lower row terminal  18  and the lower row fixing hole  124 , except for additional descriptions, please refer to the relevant descriptions of the upper row terminal  16  and the upper row fixing hole  122 , which will not be described in addition. Please also refer to  FIG. 7  and  FIG. 8 . The fixed portion  164  of the upper row terminal  16  has a first side surface  164   a  and a second side surface  164   b  opposite to the first side surface  164   a  in a first direction D 1 . The fixed portion  164  includes a main body  1642 , a first abutting portion  1644 , and a second abutting portion  1646 . The first abutting portion  1644  and the second abutting portion  1646  protrude in a second direction D 2  perpendicular to the first direction D 1 . The main body  1642  extends in a third direction D 3  perpendicular to the first direction D 1  and the second direction D 2  and connects the first abutting portion  1644  and the second abutting portion  1646 . In the upper row terminal  16  as a whole, the fixed portion  164  extends in the third direction D 3  while the contact portion  162  and the connection portion  166  extend in the third direction D 3  from two opposite ends of the fixed portion  164  respectively. In the first direction D 1 , the upper row fixing hole  122  has a first inner sidewall  1222  and a second inner sidewall  1224  opposite to the first inner sidewall  1222 . In the second direction D 2 , the upper row fixing hole  122  has a third inner sidewall  1226  and a fourth inner sidewall  1228  opposite to the third inner sidewall  1226 , which are located between the first inner sidewall  1222  and the second inner sidewall  1224 . The fixed portion  164  abuts against the upper row fixing hole  122  through the first abutting portion  1644  and the second abutting portion  1646  such that the upper row terminal  16  is fixed in the insulation housing  12  (i.e. the fixed portion  164  is fixed in the upper row fixing hole  122 ). In the embodiment, the upper row terminal  16  is inserted into the upper row fixing hole  122  in the third direction D 3 . The second abutting portion  1646  is located between the first abutting portion  1644  and the contact portion  162 . Therefore, in principle, an outer dimension L 1  of the first abutting portion  1644  in the second direction D 2  is larger than an outer dimension L 2  of the second abutting portion  1646  in the second direction D 2 , so that the upper row terminal  16  can be inserted smoothly into the upper row fixing hole  122  and the upper row fixing hole  122  can keep holding both the first abutting portion  1644  and the second abutting portion  1646 . 
     In the embodiment, both the first abutting portion  1644  and the second abutting portion  1646  include two structures protruding from two sides of the main body  1642  in the second direction D 2 ; thereby, both the first abutting portion  1644  and the second abutting portion  1646  can abut against the third inner sidewall  1226  and the fourth inner sidewall  1228  simultaneously. However, in practice, it is practicable that the first abutting portion  1644  or the second abutting portion  1646  can be a structure protruding from one side of the main body  1642  in the second direction D 2  (e.g. the lower protruding structure of the fixed portion  164  which protrudes in the second direction D 2  and abuts against the fourth inner sidewall  1228 , while the upper side of the fixed portion  164  is modified to be flat and abuts against the third inner sidewall  1226 ). 
     Furthermore, in the embodiment, the upper row fixing hole  122  has two recesses  1227  and  1229  oppositely formed in the second direction D 2  (extending in the direction D 3 ), of which the widths (i.e. the intervals in the first direction D 1 ) are substantially equal to the thickness of the upper row terminal  16  in the first direction D 1  (for example, the thickness of the upper row terminal  16  would be the thickness of a metal strip by which the upper row terminal  16  is made). The structure design therefor makes the upper row terminal  16  to be inserted smoothly into the upper row fixing hole  122  and positioned therein. In practice, the fixed portion  164  can be accommodated in the recesses  1227  and  1229  only through the first abutting portion  1644  and the second abutting portion  1646 . Furthermore, in the embodiment, the main body  1642  loosely fits in the upper row fixing hole  122 , so the retaining force between the upper row terminal  16  with the upper row fixing hole  122  can be determined easily by controlling the structural interference of the first abutting portion  1644  and the second abutting portion  1646  with the upper row fixing hole  122  (i.e. the third inner sidewall  1226  and the fourth inner sidewall  1228  thereof). However, in practice, the main body  1642  also can be disposed to structurally interfere with the upper row fixing hole  122 , which also can contributes to the retaining force. In addition, in  FIG. 8 , the section of the upper row terminal  16  is not up and down symmetrical relative to the upper row fixing hole  122 , which is due to the fact that the first abutting portion  1644  is embedded in the fourth inner sidewall  1228  (i.e. by pushing down the fourth inner sidewall  1228 ), which also can be understood by  FIG. 7  (i.e. a side view of a portion of the electrical connector  1 ). 
     In the embodiment, when the fixed portion  164  is fixed in the upper row fixing hole  122 , the first side surface  164   a  faces the first inner sidewall  1222  and is kept away from the first inner sidewall  1222  by a first distance W 1  and the second side surface  164   b  faces the second inner sidewall  1224  and is kept away from the second inner sidewall  1224  by a second distance W 2 , so that the first side surface  164   a  and the first inner sidewall  1222  can form an air band therebetween and so do the second side surface  164   b  and the second inner sidewall  1224 . In practice, the first side surface  164   a  and the second side surface  164   b  are substantially parallel to the first inner sidewall  1222  and the second inner sidewall  1224  respectively. The impedance of the electrical connector  1  also can be adjusted (or changed) by designing the first distance W 1  and the second distance W 2 . In practice, the first distance W 1  and the second distance W 2  can be designed but not limited to be equal to or larger than a third of an outer dimension W 0  of the fixed portion  164  in the first direction D 1  (i.e. the thickness of the fixed portion  164 ). 
     In the embodiment, the fixed portion  164  has a first through hole  1648  and a second through hole  1650 , which pass through the first side surface  164   a  and the second side surface  164   b  in the first direction D 1 . When the fixed portion  164  is fixed in the upper row fixing hole  122 , the first through hole  1648  and the second through hole  1650  are located in the upper row fixing hole  122 . The impedance of the electrical connector  1  also can be adjusted (or changed) by designing the sizes of the first through hole  1648  and the second through hole  1650 . In the embodiment, the first through hole  1648  and the second through hole  1650  are located at the first abutting portion  1644  and the second abutting portion  1646  respectively. Hole dimensions  1648   a  and  1650   a  of the first through hole  1648  and the second through hole  1650  in the second direction D 2  respectively are larger than an outer dimension  1642   a  of main body  1642  in the second direction D 2 ; the first through hole  1648  is larger than the second through hole  1650  (or the hole dimension  1648   a  is larger than the hole dimension  1650   a ). However, in practice the structural configuration is not limited thereto. For example, the first through hole  1648  and the second through hole  1650  can be formed somewhere else except for the first abutting portion  1644  and the second abutting portion  1646 . For another example, the hole dimensions  1648   a  and  1650   a  can be determined by ordinary trials for a required impedance of the electrical connector  1 . 
     In the embodiment, the upper row terminal  16  also includes a stop portion  168 , which extends in the second direction D 2  (or upward) from the connection portion  166 . When the fixed portion  164  is fixed in the upper row fixing hole  122 , the stop portion  168  abuts against the rear side  12   b  of the insulation housing  12 , which serves as a positioning mechanism for the insertion of the upper row terminal  16  into the upper row fixing hole  122 . By comparison, in the insertion process of the lower row terminal into the lower row fixing hole  124 , a side surface  186   a  of the connection portion  186  of the lower row terminal  18  toward the insulation housing  12  abutting against the rear side  12   b  of the insulation housing  12  serves as a positioning mechanism. Furthermore, in the embodiment, after the lower row terminal  18  is inserted into the lower row fixing hole  124 , the rear cover is assembled to the rear side  12   b  to cover the lower row fixing hole  124  and a portion of the connection portion  186  of the lower row terminal  18 . At this moment, the fixed portion  184  of the lower row terminal  18  is invisible from the rear side  12   b . The connection portion  166  of the upper row terminal  16  is exposed out of the rear cover  14  while the fixed portion  164  is covered by the stop portion  168  and the connection portion  166  in principle. The fixed portion  164  also can be regarded as being invisible in structure. Furthermore, the rear cover  14  also can provide positioning effect to the upper row terminal  16 , so that the stop portion  168  can be omitted if a side surface  166   a  of the connection portion  166  toward the upper row terminal abutting against the rear cover  14  serves as a positioning mechanism. 
     Furthermore, in the embodiment, as shown by  FIG. 1  and  FIG. 8 , the plurality of upper row terminals  16  are structurally identical and are arranged in the first direction D 1  by a first pitch P 1  (accordingly, so do the plurality of upper row fixing holes  122 ). The plurality of lower row terminals  18  are structurally identical and are in the first direction D 1  by a second pitch P 2  (accordingly, so do the plurality of lower row fixing holes  124 ). The first pitch P 1  is equal to the second pitch P 2 . However, in practice the structural configuration is not limited thereto. For example, the upper row terminals  16  and the lower row terminals  18  are arranged in the first direction D 1  by respective different pitches. In addition, the foregoing descriptions are based on the electrical connector  1  with two rows of terminals, but in practice, the foregoing descriptions are also applicable to an electrical connector with a single row of terminals. Furthermore, the foregoing descriptions are based on the female board electrical connector (i.e. the electrical connector  1 ), but in practice, the foregoing descriptions are also applicable to a male cable connector, or even an adapter, which will not be described in addition. 
     In addition, in the embodiment, the upper row terminal  16  is provided in a plate structure and can be formed by cutting a metal strip in practice. The plate structure extends parallel to the second direction D 2  and the third direction D 3 . Thereby, the plurality of upper row terminals  16  can be disposed parallel and non-coplanar in the insulation housing  12 . However, in practice, the upper row terminal  16  can be formed by bending a plate structure. The above descriptions are also applicable to the lower row terminals  18 , which will not be repeatedly described. Please refer to  FIG. 9  and  FIG. 10  which show a portion of a simplified variant of the electrical connector  1 . The simplified variant is shown with a single row of terminals  19  for description simplification. As shown by  FIG. 9  and  FIG. 10 , the terminal  19  is structurally equal to a simplified variant of the upper row terminal  16  (or the lower row terminal  18 ). Therefore, for other descriptions about the terminal  19  (and an insulation housing  13  to which the terminal  19  is assembled), please refer to the relevant descriptions of the upper row terminal  16  (or the lower row terminal  18 ), which will not be described in addition. The terminal  19  includes a contact portion  192 , a fixed portion  194 , and a connection portion  196 . The contact portion  192  and the connection portion  196  extend in the third direction D 3  from two opposite ends of the fixed portion  194 . The fixed portion  194  has a first side surface  194   a  and a second side surface  194   b  opposite to the first side surface  194   a  in the first direction D 1 . The fixed portion  194  include a main body  1942 , an abutting portion  1944 , and a through hole  1946 . The abutting portion  1944  is connected to the main body  1942  and protrudes in the second direction D 2 . The through hole  1946  is located at the abutting portion  1944  and passes through the first side surface  194   a  and the second side surface  194   b . Therein, the fixed portion  194  is fixed in a fixing hole  132  of the insulation housing  13  through the abutting portion  1944 . The fixing hole  132  has a first inner sidewall  1322  toward the first side surface  194   a  and a second inner sidewall  1324  toward the second side surface  194   b . The first side surface  194   a  is kept away from the first inner sidewall  1322  by a first distance W 1 ′. The second side surface  194   b  is kept away from the second inner sidewall  1324  by a second distance W 2 ′. A sum of the first distance W 1 ′ and the second distance W 2 ′ is larger than a third of an outer dimension W 0 ′ of the fixed portion  194  in the first direction D 1 . In the terminal  19  as a whole, the terminal  19  is provided in a bent plate structure (which is bent in a direction perpendicular to the second direction D 2 ). Adjacent two of the terminals  19  are arranged in the second direction D 2  (i.e. to be coplanar) and are fixed in the corresponding fixing holes  132 . The structure configuration is conducive to producing the terminals  19  in a way of continuous stamping (that is, the terminals  19  are all connected to a carrier strip shown in dashed lines in  FIG. 9 ) and facilitates the insertion of the terminals  19  into the fixing holes  132  of the insulation housing at the same time, which reduces the assembly cost. In practice, the combination of the terminals  19  and the insulation housing  13  assembled therewith can be expanded to be provided in a structure with two rows of terminals according to the relevant descriptions of the electrical connector  1  in the foregoing, which will not be described in addition. 
     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.