Patent Publication Number: US-11038296-B2

Title: Electric connector with rotatably mounted cover member

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2019-028545, filed on Feb. 20, 2019, the entire contents of which are incorporated herein by reference. 
     BACKGROUND 
     Japanese Unexamined Patent Publication No. 2008-192574 discloses an electrical connector including a housing in which a plurality of contacts are arranged in a predetermined direction, a fixed shell which covers the housing, and a cover member which is rotatably mounted on the fixed shell. The housing includes a front wall portion having an insertion opening into which a flexible printed circuit (FPC) is inserted. A rotation axis of the cover member is located near the front wall portion to extend along the front wall portion. 
     SUMMARY 
     An example electrical connector is disclosed herein, including a main body comprising an insertion opening into which a connection target is inserted and an accommodation space to accommodate the connection target inserted into the insertion opening, a conductive contact held in the main body so as to be connected to the connection target in the accommodation space, and a cover member rotatably mounted on the main body to be rotatable around a rotation axis passing through the main body. The cover member may include a release operation portion configured to receive an external force to rotate the cover member around the rotation axis, and a restricting member configured to switch, in response to the rotation of the cover member, between a first state in which removal of the connection target from the accommodation space is restricted and a second state in which the connection target is released. The insertion opening may be spaced apart from, and opens away from, the rotation axis. A distance between the release operation portion and the insertion opening is less than a distance between the rotation axis and the insertion opening. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view illustrating an example electrical connector. 
         FIG. 2  is a top view illustrating the example electrical connector of  FIG. 1 . 
         FIG. 3  is a side view illustrating the example electrical connector of  FIG. 1 . 
         FIG. 4  is a cross-sectional view taken along line IV-IV of  FIG. 2 . 
         FIG. 5  is a cross-sectional view taken along line V-V of  FIG. 2 . 
         FIG. 6  is a perspective view illustrating an example main body. 
         FIG. 7  is a top view illustrating the example main body of  FIG. 6 . 
         FIG. 8  is a perspective view illustrating an example cover member when seen from above. 
         FIG. 9  is a perspective view illustrating the example cover member of  FIG. 8  when seen from below. 
         FIG. 10  illustrates an example of the cover member mounted on the main body. 
         FIGS. 11A and 11B  illustrate another example of the cover member mounted on the main body. 
         FIG. 12  is a perspective view of an example electrical connector in a state in which the cover member is open with respect to the main body when seen from rear. 
         FIG. 13  is a cross-sectional view of the electrical connector of  FIG. 12 . 
         FIG. 14  is a cross-sectional view of the electrical connector configured to be connected to a signal transmission member. 
         FIG. 15  is another cross-sectional view of the electrical connector configured to be connected to the signal transmission member. 
         FIG. 16  is a cross-sectional view of another example electrical connector. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description, with reference to the drawings, the same reference numbers are assigned to the same components or to similar components having the same function, and overlapping description is omitted. When an orthogonal coordinate system defined by an X-axis, a Y-axis, and a Z-axis is shown in the drawings, a positive direction of the Z-axis may be referred to as an “upward direction” and a negative direction of the Z-axis may be referred to as a “downward direction”. 
     An example electrical connector  1  will be described with reference to  FIGS. 1 to 5 . The electrical connector  1  includes a main body  100  and a cover member  200 . The electrical connector  1  may be mounted on a circuit board  2  as shown in  FIGS. 1 to 3 . The electrical connector  1  may be configured so that a signal transmission medium  3  (a connection target) can be inserted and removed. In a state in which the signal transmission medium  3  is mounted on the electrical connector  1 , an electrical signal is transmitted between the signal transmission medium  3  and the circuit board  2  via the electrical connector  1 . 
     The circuit board  2  is configured so that an electronic circuit can be mounted thereon. The circuit board  2  may be, for example, a printed wiring board, a flexible printed board, or the like. The electrical connector  1  is mounted on a main surface of the circuit board  2  by solder connection or the like. The circuit board  2  may be disposed in a casing  4  having an opening portion  4   a , for example, as shown in  FIG. 3 . 
     As shown in  FIGS. 1 to 3 , the signal transmission medium  3  has a flat plate shape and is configured so as to transmit an electrical signal. The signal transmission medium  3  may be, for example, a flexible flat cable (FFC), a flexible printed circuit (FPC), or the like. The signal transmission medium  3  includes an insulating base material  3   a  and a plurality of signal lines  3   b  (signal transmission members). A pair of cut-out portions  3   c  (recesses) are provided on each of side edges in the vicinity of a distal end of the insulating base material  3   a . The plurality of signal lines  3   b  are disposed on an upper surface of the insulating base material  3   a  to be adjacent in a width direction (a Y-axis direction) of the insulating base material  3   a  and to extend in a lengthwise direction (an X-axis direction) of the insulating base material  3   a.    
     Subsequently, an example configuration of the main body  100  will be described in more detail with reference to  FIGS. 1 to 7 . The main body  100  includes a housing  110 , a plurality of contacts  120 , and a shell  130 . 
     The housing  110  has an insulating property and has a rectangular parallelepiped shape. The housing  110  may be formed by, for example, resin molding. In some examples, as shown in  FIG. 4 , an accommodation space  111  capable of accommodating the signal transmission medium  3  is provided in the housing  110 . Therefore, an insertion opening  112  of the signal transmission medium  3  is provided in a front portion of the housing  110  to communicate with the accommodation space  111 . 
     The insertion opening  112  is a slit-shaped opening which is surrounded by a bottom wall portion  113 , a top wall portion  114 , a rear wall portion  115 , and a pair of side wall portions  116  of the housing  110 . The insertion opening  112  extends in a width direction of the housing  110  (the Y-axis direction). The top wall portion  114  extends between the insertion opening  112  and the rear wall portion  115 . A pair of through holes  117  which extend through the top wall portion  114  to allow the outside to communicate with the accommodation space  111  are provided in the top wall portion  114 . 
     The plurality of contacts  120  have conductivity and constitute a signal transmission line for transmitting an electrical signal between the signal transmission medium  3  and the circuit board  2 . The plurality of contacts  120  may be, for example, metal members formed by bending. The plurality of contacts  120  are held by the housing  110 . 
     The plurality of contacts  120  may be, for example, press-fitted into the housing  110  or may be integrally formed with the housing  110  (by insert molding). The plurality of contacts  120  are located adjacent to each other in the width direction of the housing  110  (the Y-axis direction). Therefore, the plurality of contacts  120  are arranged to respectively correspond to the plurality of signal lines  3   b  of the signal transmission medium  3 . 
     In some examples, as shown in  FIG. 4 , a distal end portion  121  of each of the contacts  120  is located in the accommodation space  111  of the housing  110 . When the signal transmission medium  3  is inserted into the accommodation space  111 , the distal end portion  121  is physically and electrically connected to the signal line  3   b . A base end portion  122  of the contact  120  extends to the outside of the rear wall portion  115  through the rear wall portion  115  located on the side opposite to the insertion opening  112 . When the electrical connector  1  is mounted on the circuit board  2 , the base end portion  122  is electrically and physically connected to a signal electrode of the circuit board  2  by, for example, soldering. 
     The shell  130  has conductivity and is configured to prevent leakage of electromagnetic waves from the contact  120  to the outside of the electrical connector  1 . Additionally, the shell  130  may be configured to prevent mixing of noise into an electrical signal transmitted by the contact  120  due to the electromagnetic waves from outside the electrical connector  1 . In some examples, the shell  130  serves as a noise shielding member, and may include a metal member formed by bending. 
     The shell  130  is mounted on the housing  110  to cover the housing  110 , as shown in  FIG. 4 . As shown in  FIGS. 1 to 7 , the shell  130  includes a top plate  131 , a bottom plate  132 , a rear plate  133 , and a pair of side plates  134  (side wall portions). 
     The top plate  131  covers the top wall portion  114  of the housing  110 . As shown in  FIGS. 1, 2, 4, 6, and 7 , a pair of bent portions  131   a  (first locked portions) and a plurality of ground terminals  131   b  are provided at a front edge portion of the top plate  131 . A pair of protruding pieces  131   c  (stopper portions) and a pair of through holes  131   d  (second locked portions) are provided on the top plate  131 . 
     Each of the bent portions  131   a  extends toward the bottom plate  132  while bending from the vicinity of both ends in a width direction of the top plate  131  (the Y-axis direction), as shown in  FIGS. 6 and 7 . The pair of bent portions  131   a  cover a front edge portion of the housing  110  to such an extent that the bent portions  131   a  do not overlap the insertion opening  112  of the housing  110  (or cover at least part of an end face  110   a  of the main body  100  where the insertion opening  112  is located). 
     The plurality of ground terminals  131   b  are disposed adjacent to each other and are located between the pair of bent portions  131   a  in the width direction of the top plate  131  (the Y-axis direction). The plurality of ground terminals  131   b  are bent along the front edge portion of the housing  110  to the inside of the insertion opening  112 , as shown in  FIG. 4 . When the signal transmission medium  3  is inserted into the accommodation space  111 , the plurality of ground terminals  131   b  are physically and electrically connected to a ground transmission path of the signal transmission medium  3 . 
     The pair of protruding pieces  131   c  are, for example, metal pieces obtained by cutting and bending a part of the top plate  131 , as shown in  FIGS. 1 and 6 . As will be described in further detail later, the pair of protruding pieces  131   c  serve as stoppers which limit a rotation range of the cover member  200 . For example, the cover member  200  may be configured to come into contact with the pair of protruding pieces  131   c  when an elevation angle of the cover member  200  reaches a predetermined size, such that the pair of protruding pieces  131   c  hinder rotation of the cover member  200 . 
     The pair of protruding pieces  131   c  are arranged in the width direction of the top plate  131  (the Y-axis direction). The pair of protruding pieces  131   c  may be located at a center portion of the top plate  131  in the width direction of the top plate  131  (the Y-axis direction). Here, when it is assumed that a width of the top plate  131  is A, the “center portion” may be within a range of 0.2 A to 0.8 A from one side edge (for example, a left end edge of  FIGS. 2 and 7 ) of the top plate  131  in the width direction of the top plate  131  (the Y-axis direction). 
     One of protruding pieces  131   c  (a first protruding piece) may be located in a range of 0.2 A to 0.4 A from one side edge (for example, the left end edge in  FIGS. 2 and 7 ) of the top plate  131  in the width direction of the top plate  131  (the Y-axis direction). The other one of the protruding pieces  131   c  (a second protruding piece) may be located in a range of 0.6 A to 0.8 A from one side edge (for example, the left end edge in  FIGS. 2 and 7 ) of the top plate  131  in the width direction of the top plate  131  (the Y-axis direction). 
     As shown in  FIGS. 1, 2, 6, and 7 , the pair of through holes  131   d  are arranged in the width direction of the top plate  131  (the Y-axis direction). Each of the through holes  131   d  corresponds to a through hole  117  provided in the top wall portion  114  of the housing  110 . Therefore, as particularly shown in  FIG. 4 , each of the through holes  131   d  communicates with the corresponding through hole  117 . 
     The bottom plate  132  is disposed to face the top plate  131  in a height direction of the main body  100  (the Z-axis direction), as shown in  FIG. 4 . The bottom plate  132  is integrally connected to the top plate  131  via a pair of connecting portions  135 . 
     As shown in  FIG. 4 , a main portion  132   a  of the bottom plate  132  is located in the accommodation space  111  to extend along the bottom wall portion  113  of the housing  110 . When the signal transmission medium  3  is inserted into the accommodation space  111 , the main portion  132   a  of the bottom plate  132  is physically and electrically connected to the ground transmission path of the signal transmission medium  3 . 
     A plurality of bent pieces  132   b  are provided at a distal end edge of the main portion  132   a . The plurality of bent pieces  132   b  are bent toward the side away from the top plate  131  while protruding outward in a depth direction of the main body  100  (the X direction). The plurality of bent pieces  132   b  constitute fixing portions FR In some examples, in a state in which the electrical connector  1  is mounted on the circuit board  2 , each of the plurality of bent pieces  132   b  is electrically and physically connected to a ground electrode of the circuit board  2  by, for example, soldering. 
     The rear plate  133  covers the rear wall portion  115  at a position away from the rear wall portion  115  of the housing  110 , as shown in  FIG. 4 . Therefore, the base end portion  122  of the contact  120  is located in a space between the rear plate  133  and the rear wall portion  115 . 
     Each of the side plates  134  covers the side wall portion  116  of the housing  110  as shown in  FIGS. 1 to 3 and 5 to 7 . Since the pair of side plates  134  have a substantially mirror-symmetric relationship with each other, only a configuration of one side plate  134  (a first side plate) will be described below, and description of the other side plate  134  (a second side plate) will be omitted. 
     As shown in  FIG. 6 , a recess  134   a  (a first engaging portion, a third engaging portion, a state maintaining portion) which is recessed inward is provided in the vicinity of a distal end portion of the side plate  134 . The recess  134   a  is configured to be able to accommodate a protruding portion  222   a  which will be described in additional detail later. The recess  134   a  may have, for example, a rectangular shape, a circular shape, or an elliptical shape. Instead of the recess  134   a , a through hole which passes through the side plate  134  may be provided in the side plate  134  in some examples. 
     A through hole  134   b  (a bearing hole, an opening portion) is provided in the side plate  134  as shown in  FIGS. 5 and 6 . The through hole  134   b  may have a rectangular shape which extends lengthwise in the height direction of the main body  100  (the Z-axis direction). The through hole  134   b  may be located in a center portion of the side plate  134  in the depth direction of the main body  100  (the X-axis direction) or may be located closer to the insertion opening  112  than the center portion of the side plate  134  in the depth direction of the main body  100  (the X-axis direction). 
     A plurality of bent pieces  134   c  are provided on a lower end edge of the side plate  134 . The plurality of bent pieces  134   c  also constitutes fixing portions FP. The plurality of bent pieces  134   c  are bent from the side plate  134  to protrude outward in the width direction of the main body  100  (the Y direction). 
     An auxiliary plate  134   d  (an auxiliary wall portion) is provided at a lower end edge of the side plate  134  to be bent from the lower end edge. In some examples, the auxiliary plate  134   d  is integrally connected to the side plate  134  via the bent portion  134   e . The bent portion  134   e  may constitute the fixing portion FP to the circuit board  2  as described above. For example, the auxiliary plate  134   d  faces the side plate  134  in the width direction of the main body  100  (the Y-axis direction). When the electrical connector  1  is mounted on the circuit board  2 , the auxiliary plate  134   d  and the bent portion  134   e  may be electrically and physically connected to the ground electrode of the circuit board  2  by, for example, soldering. Therefore, the auxiliary plate  134   d  and the bent portion  134   e  may serve as a fixing portion which is fixed to the circuit board  2 . 
     A rotation shaft  134   f  is provided on a side edge of the auxiliary plate  134   d . The rotation shaft  134   f  may be obtained by bending a part of the auxiliary plate  134   d  so that the rotation shaft  134   f  extends in the width direction of the main body  100  (the Y-axis direction) from the auxiliary plate  134   d  toward the side plate  134 . A distal end of the rotation shaft  134   f  is inserted into the through hole  134   b . In some examples, the distal end of the rotation shaft  134   f  is engaged with the through hole  134   b.    
     With reference to  FIG. 5 , the distal end of the rotation shaft  134   f  may pass through the through hole  134   b  to approach the housing  110 . Therefore, the rotation shaft  134   f  may be located at the center portion of the side plate  134  in the depth direction of the main body  100  (the X-axis direction) or may be located closer to the insertion opening  112  than the center portion of the side plate  134  in the depth direction of the main body  100  (the X-axis direction), similarly to the through hole  134   b.    
     The rotation shaft  134   f  includes an inclined portion  134   g  (a side edge portion) as shown in  FIG. 5 . The inclined portion  134   g  (a portion which faces the top plate  131  side) may include a peripheral edge of the rotation shaft  134   f  which faces the side opposite to the bent portion  134   e . The inclined portion  134   g  is inclined toward the bent portion  134   e  such that the height of the rotation shaft  134   f  decreases in the direction of the distal end portion of the rotation shaft  134   f . In some examples, the rotation shaft  134   f  has a tapered shape. 
     Subsequently, an example configuration of the cover member  200  will be described in more detail with reference to  FIGS. 1  to  5 ,  8  and  9 . The cover member  200  is rotatably mounted on the main body  100  so as to be rotatable around a rotation axis Ax 1 . For example, both ends of the cover member  200  in a direction along the rotation axis Ax 1  (a pair of side plates  220 ) is mounted on the main body  100  so as to rotate around the rotation axis Ax 1 . The insertion opening  112  is spaced apart from, and opens away from, the rotation axis Ax 1 . The insertion opening  112  opens in a direction OD 1  which is a direction away from the rotation axis Ax 1 . A plurality of contacts  120  are held by the main body  100  so as to be arranged along the rotation axis Ax 1 . The plurality of signal lines  3   b  are arranged along the rotation axis Ax 1 . Each of the plurality of contacts  120  are connected to one of the plurality of signal lines  3   b  in the accommodation space  111 . The insertion opening  112  extends in a slit shape along the rotation axis Ax 1 . The main body  100  comprises a side face  134   y  (an outer face of the side plate  134 ) intersecting (for example, orthogonally intersecting) the rotation axis Ax 1  at an intersection  134   z . The through hole  134   b  is formed at the intersection  134   z  of the rotation axis Ax 1  and the side face  134   y . The recess  134   a  is provided on the side face  134 . The main body  100  comprises a back face  133   a  (an outer face of the back plate  133 ) which faces away from the opening direction OD 1  of the insertion opening  112 . A distance D 1  between the rotation axis Ax 1  and the insertion opening  112  may be less than or equal to a distance D 4  between the rotation axis Ax 1  and the back face  133 . The cover member  200  includes a main plate  210 , the pair of side plates  220  (both ends of the cover member  200 ), a bent portion  230  (a first locking portion), a pair of restricting members  240  (a second locking portion), and a release operation portion  250 . The cover member  200  may be, for example, a metal member formed by bending. 
     The main plate  210  protrudes toward the opening direction OD 1  of the insertion opening  112  from a base end portion  210   b  along the rotation axis Ax 1 , overlaps the main body  100  in a first state which will be described later, and is separated from the main body  100  in a second state which will be described later. The base end portion  210   b  is located between the rotation axis Ax 1  and a distal end of the main plate  210 . In the first state, the base end portion  210   b  is located between the rotation axis Ax 1  and the insertion opening  112 . In the second state, The base end portion  210   b  of the main plate  210  comes in contact with the pair of protruding pieces  131   c . Thus, a displacement of the main plate  210  away from the main body  100  is restricted. The pair of protruding pieces  131   c  are located between the both ends  220  of the cover member  200  in a direction along the rotation axis Ax 1 . The main plate  210  extends in the width direction of the cover member  200  (the Y-axis direction), as shown in  FIGS. 1 and 2 . In a state in which the cover member  200  overlaps the top plate  131  (when the cover member  200  is closed with respect to the main body  100 ), the main plate  210  covers a region of the top plate  131  which is closer to the insertion opening  112  than the protruding piece  131   c.    
     As shown in  FIGS. 1, 3, 8, and 9 , each of the side plates  220  extends toward the main body  100  while being bent from both side edges of the main plate  210 . A shaft hole  221  which is a through hole passing through the side plate  220  is provided at a rear end portion of the side plate  220  (an end portion on the rear plate  133  side). With reference to  FIGS. 1 and 3 , the rotation shaft  134   f  is inserted into the shaft hole  221 . Therefore, the cover member  200  is mounted on the main body  100  (the shell  130 ) to be rotatable around the rotation shaft  134   f . The rotation shaft  134   f  extends into the through hole  134   b  via the shaft hole  221 . The rotation shaft  134   f  may extend into the housing  110  (for example, into a recess  110   c  formed on the side face  110   b  of the housing  110 ) via the shaft hole  221  and the through hole  134   b . The rotation shaft  134   f  comprises a first edge portion which faces toward the bent portion  134   e  and a second edge portion (the inclined portion  134   g  as described above) which faces away from the bent portion  134   e . The first edge portion  134   x  may be parallel to the rotation axis Ax 1 . The second edge  134   g  may be inclined with respect to the rotation axis Ax 1  so that a distance between the second edge portion  134   g  and the first edge portion  134   x  gradually decreases toward the distal end of the rotation shaft  134   f.    
     As shown in  FIGS. 8 and 9 , a protruding portion  222   a  (a second engaging portion, a fourth engaging portion, a state maintaining portion) which protrudes inward from an inner wall surface of the side plate  220  is provided in the vicinity of a distal end portion  222  of the side plate  220 . The protruding portion  222   a  is engaged with the recess  134   a  in the first state. The protruding portion  222 , while engaging with the recess  134   a , oppose a positional displacement of the main plate  210  from the first state to the second state. With reference to  FIGS. 1 and 3 , in a state in which the cover member  200  overlaps the top plate  131  (when the cover member  200  is closed with respect to the main body  100 ), the protruding portion  222   a  is engaged with the recess  134   a  by being accommodated in the recess  134   a . The protruding portion  222   a  may be formed by embossing the side plate  220 , for example. A protruding height of the protruding portion  222   a  may be equal to or less than a half of a thickness of the side plate  220  or may be smaller than a depth of the recess  134   a.    
     Each of the bent portions  230  extends toward the main body  100  while being bent from the vicinity of both ends of the cover member  200  in the width direction (the Y-axis direction), as shown in  FIGS. 8 and 9 . In the state in which the cover member  200  overlaps the top plate  131  (when the cover member  200  is closed with respect to the main body  100 ), the pair of bent portions  230  cover surfaces of the bent portions  131   a  to such an extent that the bent portions  230  do not overlap with the insertion opening  112  of the housing  110 . In some examples, each of the bent portions  230  is locked by the corresponding bent portion  131   a.    
     The restricting member  240  switches, in response to a rotation of the cover member  200  around the rotation axis Ax 1 , the first state in which removal of the signal transmission medium  3  from the accommodation space  111  is restricted and the second state in which the signal transmission medium  3  is released. The restricting member  240  is provided on the main plate  210 . The main body  100  comprises a through hole (the through holes  117  and  131   d ). An end portion  240   a  of the restricting member  240  protrudes into the accommodation space  111  in the first state. The end portion  240   a  of the restricting member  240  is located in the cut-out portions  3   c  in the first state and is located out of the cut-out portions  3   c  in the second state. The plurality of contacts  120  are sandwiched between the two restricting members  240  along the rotation axis Ax 1 . The pair of restricting members  240  are, for example, metal pieces obtained by cutting and bending a part of the main plate  210  as shown in  FIGS. 8 and 9 . The pair of restricting members  240  are configured to lock the signal transmission medium  3  inserted into the insertion opening  112  and thus to restrict removal of the signal transmission medium  3  from the housing  110  (as described in additional detail later). 
     The pair of restricting members  240  are arranged in a width direction of the main plate  210  (the Y-axis direction). With reference to  FIGS. 1, 2, and 4 , in the state in which the cover member  200  overlaps the top plate  131  (when the cover member  200  is closed with respect to the main body  100 ), the pair of restricting members  240  are respectively inserted into the corresponding through holes  117  and  131   d . In some examples, the pair of restricting members  240  are respectively locked in the corresponding through holes  117  and  131   d  such that a distal end portion of each of the restricting members  240  is located in the accommodation space  111 . 
     The release operation portion  250  is configured to receive an external force to rotate the cover member  200  around the rotation axis Ax 1 . The release operation portion  250  is configured to perform an operation for releasing a lock (described in additional detail later) between the signal transmission medium  3  and the restricting member  240 . A position where the two protruding pieces  131   c  come in contact with the base end portion  210   b  and a width of the release operation portion  250  overlap with each other in a direction along the rotation axis Ax 1 . A center of the release operation portion  250  is located between the two protruding pieces  131   c  along the rotation axis Ax 1 . A distance D 2  between the release operation portion  250  and the insertion opening  112  is less than a distance D 1  between the rotation axis Ax 1  and the insertion opening  112 . The release operation portion  250  is provided on a distal end of the main plate  210  opposite to the base end portion  210   b . The release operation portion  250  extends in the width direction of the main plate  210  (the Y-axis direction). The release operation portion  250  is bent from a distal end edge of the main plate  210 , so as to be bent away from the main body  100  toward a distal end thereof and thus to be easily gripped by an operator. In some examples, in the state in which the cover member  200  overlaps the top plate  131  (when the cover member  200  is closed with respect to the main body  100 ), the release operation portion  250  is located closer to the insertion opening  112  than the rotation shaft  134   f . The release operation portion  250  is formed so as to be apart from the main body  100  toward the opening direction OD 1  of the insertion opening  112 . A distance D 3  between the release operation portion  250  and the main body  100  increases gradually toward the opening direction OD 1 . This configuration facilitates gripping by an operator. 
     Example Method of Mounting a Cover Member on Main Body 
     Subsequently, a method of mounting the cover member  200  on the main body  100  will be described with reference to  FIGS. 10, 11A , and  11 B. 
     First, as shown in  FIG. 10 , the auxiliary plate  134   d  is inclined with respect to the bent portion  134   e  so that a distal end of the auxiliary plate  134   d  is tilted away from the side plate  134 . Therefore, the rotation shaft  134   f  is located outside the through hole  134   b . Additionally, a linear distance between the distal end of the rotation shaft  134   f  and the side plate  134  may be set smaller than a thickness of the side plate  220 . 
     When the cover member  200  is moved closer to the main body  100  from the vicinity of the top plate  131 , as shown in  FIG. 11A , the side plate  220  comes into contact with the inclined portion  134   g  of the rotation shaft  134   f  and pushes the auxiliary plate  134   d  outward. When the cover member  200  is further moved closer to the main body  100  and the distal end of the rotation shaft  134   f  overlaps the shaft hole  221  of the side plate  220 , as shown in  FIG. 11B , the auxiliary plate  134   d  and the rotation shaft  134   f  return to the configuration illustrated in  FIG. 10  due to a spring property of the auxiliary plate  134   d , and thus the distal end of the rotation shaft  134   f  is naturally inserted into the shaft hole  221 . 
     Thereafter, as shown in  FIG. 5 , the rotation shaft  134   f  is inserted into the shaft hole  221  and is engaged with the through hole  134   b  by pushing the rotation shaft  134   f  into the through hole  134   b.    
     Accordingly, the cover member  200  is mounted on the main body  100  to be rotatable around the rotation shaft  134   f . Thus, the electrical connector  1  is completed. 
     Method of Mounting a Signal Transmission Medium in the Electrical Connector 
     Next, an example method of mounting the signal transmission medium  3  in the electrical connector  1  will be described with reference to  FIGS. 12 to 15 . 
     First, as shown in  FIGS. 12 and 13 , the operator grips the release operation portion  250  and then lifts the cover member  200  with respect to the main body  100 . When the cover member  200  is lifted to a predetermined elevation angle, the base end portion  210   b  of the main plate  210  comes into contact with the protruding piece  131   c , and rotation of the cover member  200  is hindered. In some examples, a rotation range of the cover member  200  is limited to a range of the predetermined elevation angle due to the presence of the protruding piece  131   c . Additionally, a distal end of the restricting member  240  is retracted from the accommodation space  111  and is located in the through holes  117  and  131   d.    
     Next, as shown in  FIG. 14 , the signal transmission medium  3  is inserted into the accommodation space  111  from the insertion opening  112 . Thus, each of the plurality of signal lines  3   b  is physically and electrically connected to the corresponding contact  120 . Further, the ground transmission path of the signal transmission medium  3  is physically and electrically connected to the ground terminals  131   b  or the main portion  132   a  of the bottom plate  132 . Additionally, the cut-out portions  3   c  of the signal transmission medium  3  overlap the through holes  117  and  131   d  when seen in a height direction of the electrical connector  1  (the Z-axis direction). 
     Next, as shown in  FIG. 15 , the cover member  200  is brought close to the main body  100 , and the cover member  200  overlaps the shell  130 . Accordingly, the distal end of the restricting member  240  is located within the cut-out portion  3   c  of the signal transmission medium  3 . Thus, the removal of the signal transmission medium  3  from the electrical connector  1  is restricted by the distal end of the restricting member  240 . 
     When the cover member  200  approaches the main body  100  while the distal end portion  222  of the side plate  220  is slightly deformed (refer to  FIGS. 11A and 11B ), the protruding portion  222   a  enters the recess  134   a  and is locked in the recess  134   a . Therefore, even when some external force acts on the cover member  200 , the cover member  200  is maintained in a closed state to overlap the main body  100  due to the recess  134   a  and the protruding portion  222   a.    
     The signal transmission medium  3  can be separated from the electrical connector  1  by performing a reverse procedure of the above. 
     Additional Operations 
     As shown in  FIG. 3 , even when the electrical connector  1  is installed in a narrow casing  4 , a sufficient space for the signal transmission medium  3  to pass through is secured on the insertion opening  112  side. Therefore, although there is limited space on the rear wall portion  115  side of the housing  110 , as described above, when the release operation portion  250  is located closer to the insertion opening  112  than the rotation shaft  134   f  in the state in which the cover member  200  overlaps the top plate  131  (when the cover member  200  is closed with respect to the main body  100 ), the operator can grip the release operation portion  250  located close to the insertion opening  112  and can operate the cover member  200 . 
     In some examples, the rotation shaft  134   f  can be located at the center portion of the side plate  134  or located closer to the insertion opening  112  than the center portion of the side plate  134  in the depth direction of the main body  100  (the X-axis direction). Therefore, when the cover member  200  is opened and closed, the cover member  200  does not pass around the rear wall portion  115 . Thus, even when the electrical connector  1  is installed in a narrow region, interference of the cover member  200  with other members (such as the casing  4 ) may be prevented. 
     In some examples, the rotation shaft  134   f  can be located at the center portion of the side plate  134  or located closer to the insertion opening  112  than the center portion of the side plate  134  in the depth direction of the main body  100  (the X-axis direction). Therefore, when the release operation portion  250  of the cover member  200  is lifted until the elevation angle of the cover member  200  reaches a predetermined size, the release operation portion  250  is lifted higher than in a configuration in which the rotation shaft  134   f  is located close to the rear wall portion  115 . Thus, the connection target may be released or unlocked by the restricting member due to the relatively small operation of the cover member. 
     In some examples, the protruding piece  131   c  which serves as a stopper for limiting the rotation range of the cover member  200  is provided on the top plate  131  (the shell  130 ). Therefore, the rotation range of the cover member  200  may be limited to a predetermined range by the protruding piece  131   c . Therefore, even when the electrical connector  1  is installed in a narrow region, a movable space for the cover member  200  is secured. 
     In some examples, when the elevation angle of the cover member  200  reaches a predetermined size, the cover member  200  comes into contact with the protruding piece  131   c.    
     In some examples, the protruding piece  131   c  may be located at the center portion of the top plate  131  in the width direction of the top plate  131  (the Y-axis direction). Accordingly, even when the cover member  200  is opened very wide with respect to the main body  100 , a load easily acts on the main body  100  via the protruding piece  131   c . Thus, the load which can act on the rotation shaft  134   f  may be reduced. 
     In some examples, when it is assumed that the width of the top plate  131  is A, one protruding piece  131   c  can be located within a range of 0.2 A to 0.4 A, and the other protruding piece  131   c  can be located within a range of 0.6 A to 0.8 A in the width direction of the top plate  131  (the Y-axis direction). Accordingly, even when the cover member  200  is repeatedly operated over a period of time, stress may be readily dispersed to the cover member  200  and the main body  100 . Therefore, the load which can act on the rotation shaft  134   f  may be further reduced. 
     In some examples, in the state in which the cover member  200  overlaps the top plate  131  (when the cover member  200  is closed with respect to the main body  100 ), the protruding portion  222   a  is locked in the recess  134   a . Therefore, even when an unexpected external force acts on the cover member  200 , inadvertent or unintended opening of the cover member  200  may be prevented. 
     In some examples, the top plate  131  of the shell  130  covers the entire top wall portion  114 . Therefore, even when the signal transmission medium  3  inserted into the insertion opening  112  is displaced up and down (also referred to as “warping”), the warping of the signal transmission medium  3  is prevented by the presence of the shell  130 . Thus, inadvertent or unintended lifting of the cover member  200  may be prevented. 
     In some examples, in the state in which the cover member  200  overlaps the top plate  131  (when the cover member  200  is closed with respect to the main body  100 ), the pair of bent portions  230  are respectively locked to the corresponding bent portions  131   a , and the pair of restricting members  240  are respectively engaged with the corresponding through holes  117  and  131   d . Therefore, in the closed state, when the cover member  200  moves relative to the main body  100  in a first direction from the bent portion  131   a  toward the through holes  117  and  131   d , the bent portion  230  comes into contact with the bent portion  131   a . Therefore, the movement of the cover member  200  in the first direction is restricted by the bent portion  131   a  and the bent portion  230 . On the other hand, in the closed state, when the cover member  200  moves relative to the main body  100  in a second direction from the through holes  117  and  131   d  toward the bent portion  131   a , the restricting member  240  comes into contact with the through holes  117  and  131   d . Therefore, the movement of the cover member  200  in the second direction is restricted by the through holes  117  and  131   d  and the restricting member  240 . Accordingly, the forward and backward movement of the cover member  200  may be restricted in order to prohibit or reduce contact between the shaft hole  221  and the rotation shaft  134   f . Thus, the load acting on the rotation shaft  134   f  may be reduced while preventing rattling of the cover member  200 . 
     In some examples, the rotation shaft  134   f  which is a part of the main body  100  (the shell  130 ) is engaged with the through hole  134   b  provided in the main body  100  (the shell  130 ). The distal end portion of the rotation shaft  134   f  may be held by itself such that even when an external force acts on the rotation shaft  134   f , the distal end portion of the rotation shaft  134   f  is caught by the through hole  134   b , and thus the rotation shaft  134   f  is less likely to be separated from the through hole  134   b . Therefore, separation of the cover member  200  from the main body  100  may be prevented. 
     In some examples, the distal end portion of the rotation shaft  134   f  can pass through the through hole  134   b  to approach the housing  110 . Therefore, even when a load acts on the rotation shaft  134   f  in a direction intersecting the rotation shaft  134   f  (the X-axis direction), the distal end portion of the rotation shaft  134   f  is securely caught by the through hole  134   b  in order to prevent the inadvertent separation of the rotation shaft  134   f  from the through hole  134   b . Accordingly, the separation of the cover member  200  from the main body  100  may additionally be prevented. 
     In some examples, the auxiliary plate  134   d  and the bent portion  134   e  can serve as fixing portions which are fixed to the circuit board  2 . The auxiliary plate  134   d  and the bent portion  134   e  may be fixed to another member, such as the circuit board  2 , in order to prevent them from falling in a direction away from the side plate  134 . Thus, even when an external force acts on the rotation shaft  134   f , the distal end portion of the rotation shaft  134   f  may remain located in the through hole  134   b . Accordingly, the separation of the cover member  200  from the main body  100  may be further prevented. 
     When the auxiliary plate  134   d  and the bent portion  134   e  are fixed to the circuit board  2 , a gap generated between the shell  130  and the circuit board  2  may become smaller in order to further prevent leakage of electromagnetic waves to the outside of the electrical connector  1 , and to prevent mixing of noise into the electrical signal transmitted by the contact  120 . 
     In some examples, the inclined portion  134   g  of the rotation shaft  134   f  is inclined toward the bent portion  134   e . Accordingly, when the cover member  200  is mounted on the main body  100 , the cover member  200  is pushed toward the bent portion  134   e  when the portion of the cover member  200  in which the shaft hole  221  is formed is in contact with the inclined portion  134   g , and thus the auxiliary plate  134   d  is naturally expanded by the portion in which the shaft hole  221  is formed. When the rotation shaft  134   f  overlaps the shaft hole  221 , the rotation shaft  134   f  naturally enters the shaft hole  221  due to the spring property of the auxiliary plate  134   d  in order to facilitate attachment of the cover member  200  to the main body  100 . 
     ADDITIONAL EXAMPLES 
     It is to be understood that not all aspects, advantages and features described herein may necessarily be achieved by, or included in, any one particular example. Indeed, having described and illustrated various examples herein, it should be apparent that other examples may be modified in arrangement and detail. 
     For example, at least one protruding piece  131   c  may be provided as a stopper on the top plate  131 . The member which serves as the stopper may be provided on at least one of the cover member  200  and the main body  100 . A member other than the protruding piece  131   c  may serve as a stopper. For example, the base end portion  210   b  of the main plate  210  of the cover member  200  may serve as a stopper. 
     In some examples, the state maintaining portion may be configured to maintain the closed state in which the cover member  200  overlaps the main body  100 . Additionally, the closed state in which the cover member  200  overlaps the main body  100  may be maintained by the protruding portion provided on the distal end portion  222  and the recess provided in the side plate  134  which corresponds to the protruding portion. 
     Furthermore, the rotation shaft  134   f  may be engaged with an opening (for example, a recess, a groove portion, or the like) other than the through hole  134   b  provided in the side plate  134 . 
     Still further, the rotation shaft  134   f  may be provided on the side plate  134 , and an opening which is engaged with the rotation shaft  134   f  may be provided in the auxiliary plate  134   d.    
     Additionally, the auxiliary plate  134   d  and the bent portion  134   e  may not be fixed to another member, such as a circuit board. 
     In some examples, the top plate  131  of the shell  130  may cover at least a portion of the top wall portion  114  in which the insertion opening  112  is formed. 
     By way of further example, the electrical connector  1  may not include the shell  130 . Instead, a member corresponding to the member of the shell  130  (for example, the protruding piece  131   c , the through hole  134   b , the rotation shaft  134   f , and so on) may be configured by the housing  110 . 
     In additional examples, the rotation shaft  134   f  may be located closer to the rear plate  133  than the center portion of the side plate  134  in the depth direction of the main body  100  (the X-axis direction). 
     As shown in  FIG. 16 , the distal end portion of the rotation shaft  134   f  may have a hook shape. In some examples, when the cover member  200  is mounted on the main body  100 , and the rotation shaft  134   f  is pushed into the through hole  134   b , the distal end portion of the rotation shaft  134   f  is caught by the through hole  134   b . Therefore, after completion of the electrical connector  1 , even when an external force acts on the rotation shaft  134   f , the rotation shaft  134   f  may remain fixed to the through hole  134   b  in order to prevent the separation of the cover member  200  from the main body  100 .