Patent Publication Number: US-8523580-B2

Title: Electrical connector

Description:
BACKGROUND OF THE INVENTION AND RELATED ART STATEMENT 
     The present invention relates to an electrical connector. 
     A conventional electrical connector (a conventional connector) including a plurality of terminals held in a housing by being molded integrally is disclosed in Patent Reference. In Patent Reference, the housing of the connector includes a circumferential wall composed of a pair of sidewalls extending in a longitudinal direction thereof and a pair of end walls extending in a short direction or a direction perpendicular to the longitudinal direction. 
     The housing further includes a bottom wall provided at a lower end edge of the circumferential wall so as to cover a space surrounded by the circumferential wall from a lower direction and a protruding wall surrounded by the circumferential wall, extending in the longitudinal direction as well as protruding in an upper direction. A space is formed between the circumferential wall and the protruding wall opening in the upper direction as a receptacle recess portion for receiving a fitting portion of a mating connector.
     Patent Reference Japanese Utility Model Publication No. 11-000099   

     In the conventional connector disclosed in Patent reference, the terminal is held in the housing at a position closer to the sidewall. The terminal includes an elastic arm portion at a free end portion thereof, extending along the protruding wall. The terminal includes a horizontal base portion, the elastic arm portion, a transition portion, a downward extending portion and a connecting portion. The horizontal base portion extends in the short direction of the housing along the bottom wall of the housing. 
     The transition portion is formed by being bent the horizontal base portion at a position closer to the protruding wall in the short direction. The elastic arm portion extends in the upper direction through the transition portion. The elastic arm portion includes a contact portion at an upper end thereof. The downward extending portion extends in the lower direction obliquely, from the horizontal base portion at a position closer to the sidewall in the short direction. The downward extending portion is held in the housing. The connecting portion extends horizontally from the downward extending portion to outside of the housing. 
     The protruding wall of the housing includes a terminal groove extending in a vertical direction and opening in the upper direction, on a side surface thereof. The terminal groove is situated where corresponding to the terminal in the longitudinal direction and accommodates the transition portion and the elastic arm portion of the terminal therein. The protruding wall further includes a vertical wall portion extending in the vertical direction on both ends thereof and between the terminal grooves next to each other, in the longitudinal direction. In addition, the bottom wall has a hole opening where corresponding to the terminal in the longitudinal direction and where being close to the protruding wall in the short direction thereof. The hole opening opens so as to penetrate the bottom wall in the vertical direction. The terminal groove communicates with outside of the connector through the hole opening. 
     The housing holds the terminal partially at a position closer to the sidewall of the horizontal base portion and at the downward extending portion with a boundary region between the sidewall and the bottom wall thereof by being molded integrally. The terminal groove of the housing accommodates the transition portion and the elastic arm portion of the terminal so as to have a space from a groove bottom surface of the terminal groove in the short direction. Thereby, the elastic arm portion is capable of elastic displacement by bending toward the groove bottom surface in the short direction. 
     The transition portion and the elastic arm portion are situated so as to have a space from inner side surfaces of the terminal groove in the short direction as well. The spaces generated between the surfaces of the terminal groove and the transition portion and the elastic arm portion of the terminal is quite narrow, since the terminal groove is partially occupied by the transition portion and the elastic arm portion. 
     In the conventional connector disclosed in Patent Reference, the bottom wall of the housing has the hole opening situated underneath of the transition portion and of a portion close to the protruding wall of the horizontal base portion. Therefore, the portion close to the protruding wall of the horizontal base portion and the transition portion are capable of elastic displacement in the lower direction as the horizontal base portion is bent. Accordingly, the transition portion is displaced elastically only in the lower direction while the elastic arm portion is displaced elastically toward both of the lower direction and the groove bottom surface as described above. 
     In the conventional connector disclosed in Patent Reference, when the housing and the terminal are molded integrally, it is normally assumed that an upper mold for providing the receptacle recess portion and the terminal groove of the housing is arranged from the upper direction, and a lower mold for providing the hole opening of the bottom wall of the housing is arranged from the lower direction. As described above, in the conventional connector in Patent Reference, the transition portion and the elastic arm portion of the terminal are situated in the terminal groove. In addition, the transition portion is not allowed to be displaced elastically toward the groove bottom surface of the terminal groove. Accordingly, the upper mold is not able to displace the transition portion so as to be apart from the groove bottom surface upon being molded integrally. Therefore, the space the transition portion and the elastic arm portion of the terminal generate against the terminal groove remains narrow. As a result, it is necessary that the upper mold has a portion being small enough to correspond to the space described above. 
     These days, downsizing of connectors is highly demanding. Accordingly, in general, the space described above in the longitudinal direction is often designed to be very narrow. Therefore, it is considerably difficult to manufacture the upper mold with the portion thereof as narrow as the space described above. In case that the upper mold is able to have the portion narrow enough to correspond to the space, the upper mold has a complicated shape, resulting in difficulty in production thereof and reducing strength of the portion thereof. 
     When the space is designed to be large enough to simplify the shape of the upper mold for the purpose of ease in manufacturing of the upper mold and of obtaining enough strength of the upper mold as retaining number of the terminal grooves and size of the housing in the longitudinal direction, in other words, density of the terminals, it is necessary to make the vertical wall portion narrower. As a result, the vertical wall portion reduces strength thereof. Accordingly, obtaining the upper mold with easier manufacturing process as well as maintaining the strength thereof and maintaining the strength of the vertical wall portion are contrary to each other. Furthermore, though both conditions are satisfied, it is not preferable to enlarge both of the space and the vertical wall portion in the longitudinal direction since the connector becomes larger in the longitudinal direction. 
     In view of the problems described above, an object of the present invention is to provide an electrical connector which enables both of the mold and the housing to maintain the strength thereof as well as simplifying the shape of the mold, without enlarging the connector in size in the longitudinal direction. 
     Further objects and advantages of the invention will be apparent from the following description of the invention. 
     SUMMARY OF THE INVENTION 
     In order to attain the objects described above, according to the present invention, an electrical connector (a connector) includes a housing and a plurality of terminals disposed in the housing. The housing includes a bottom wall and a protruding wall. The bottom wall faces a surface the connector is attached to, and extends in a direction the terminal is disposed as a longitudinal direction. The protruding wall for being connected to a mating connector extends in the longitudinal direction as well as extending in an upper direction from the bottom wall. The terminal is held in the housing by being molded integrally. 
     The terminal includes a held portion for being held in the housing, a base portion, a transition portion, an elastic arm portion and a contact portion. The elastic arm portion is provided at a closer position to the protruding wall of the terminal. The base portion combines the held portion and the elastic arm portion at a position closer to the bottom wall in a vertical direction. The elastic arm portion extends in the upper direction along the protruding wall from the base portion through the transition portion being bent. The elastic arm portion is capable of elastic displacement in a short direction perpendicular to the longitudinal direction. The contact portion for contacting with a mating terminal of the mating connector is provided at an upper end portion of the elastic arm portion. 
     The protruding wall of the housing includes a plurality of vertical wall portions and a displacement receiving recess. The vertical wall portion is disposed in the protruding wall with a space in the longitudinal direction. The displacement receiving recess is depressed between the vertical wall portions next to each other, from a position where a side surface of the vertical wall portion extending in the longitudinal direction and the vertical direction is situated. The displacement receiving recess allows the elastic arm portion of the terminal to be displaced elastically. 
     In the connector described above, in the present invention, the housing has an opening penetrating the bottom wall at least at a lower side of the displacement receiving recess. The displacement receiving recess communicates with the opening. Further, the base portion and the transition portion of the terminal are situated outside of the displacement receiving recess. 
     In the connector according to the present invention, the transition portion of the terminal is incapable of elastic displacement in the short direction and is situated outside of the displacement receiving recess. Therefore, when the housing and the terminal are molded integrally, an entire space of the displacement receiving recess in the longitudinal direction can be used for a lower mold without enlarging the displacement receiving recess in the longitudinal direction. Accordingly, the displacement receiving recess can be provided by placing the lower mold utilizing the entire displacement receiving recess from the lower direction. Consequently, it is possible to obtain the lower mold having a simple shape with sufficient strength and size as well as providing the displacement receiving recess by the lower mold. 
     In case the connector is designed so that the elastic arm portion is situated in the displacement receiving recess in a free state as the connector is manufactured completely, the transition portion incapable of elastic displacement is not situated in the displacement receiving recess. In addition, upon being molded integrally, the lower mold displaces the elastic arm portion toward outside of the displacement receiving recess elastically. Therefore, it is possible to place the lower mold without obstruction. The lower mold can be extracted in the lower direction after being molded integrally through the opening in the bottom wall. 
     Either of that the elastic arm portion in the free state is situated inside or outside of the displacement receiving recess, upon being molded, the elastic arm portion is always situated outside the displacement receiving recess, in other words, in a space around the protruding wall. Accordingly, an upper mold placed from the upper direction for providing the space is able to have a groove portion opening toward the protruding wall and corresponding to the elastic arm portion so that the groove portion surrounds the elastic arm portion from three directions without being obstructed by the displacement receiving recess. Therefore, it is possible to obtain the upper mold having a simple shape. 
     As described above, the elastic arm portion of the terminal is situated outside the displacement receiving recess. Accordingly, the elastic arm portion and an inner wall surface of the displacement receiving recess have a space therebetween as opposed to the conventional connector. Consequently, the upper mold is able to have the groove portion thereof larger in the longitudinal direction, than the space between the inner surface of the displacement receiving recess and the elastic arm portion in the conventional connector. Thereby, it is possible to maintain strength of the upper mold. 
     Further, as opposed to the conventional connector, it is not necessary that the upper mold has a portion corresponding to the space described above. Therefore, it is not necessary to shrink the vertical wall portion in the longitudinal direction as enlarging the upper mold in the longitudinal direction in order to obtain the sufficient strength. As a result, the vertical wall portion is able to obtain sufficient strength. In addition, the mold and the connector are able to be strong sufficiently without being enlarge in the longitudinal direction for. Therefore, it is possible to avoid the connector from growing in size. 
     It is preferable that the protruding wall of the housing includes a regulating protrusion protruding from a side surface of the vertical wall portion. A projecting portion of the regulating protrusion regulates a position of the mating connector in the short direction as the connector is connected to the mating connector. It is preferable that the regulating protrusion is smaller in size than the vertical wall portion in the longitudinal direction. 
     As described above, as the connector is connected to the mating connector, it is possible to regulate the position of the mating connector in the short direction with the regulating protrusion. Further, the regulating protrusion is smaller in size than the vertical wall portion in the longitudinal direction. Therefore, as compared to a case that the regulating protrusion is similar in size with the vertical wall portion, it is possible to maintain a sufficient interval between the regulating protrusion and the elastic arm portion of the terminal. Accordingly, it is possible to avoid a portion corresponding to the interval of the upper mold from becoming smaller in the longitudinal direction when the housing and terminal are molded integrally. As a result, it is possible to maintain the strength of the upper mold as well as simplifying the shape of the upper mold. 
     It is preferable that the regulating protrusion of the housing is provided in any two or more of the vertical wall portions, respectively. Thereby, the position of the mating connector is satisfactorily regulated by the regulating protrusions provided in the vertical wall at the two or more positions having a distance. 
     The regulating protrusion of the housing may be situated in the vertical wall portion at an end of the protruding wall in the longitudinal direction. When the regulating protrusion is only provided in the vertical wall portion at an end of the protruding wall in the longitudinal direction, it is possible to downsize the vertical wall portion without the regulating protrusion in the longitudinal direction as the vertical wall portion situated between the displacement receiving recesses adjacent to each other does not include the regulating protrusion. Consequently, it is possible to downsize the housing, eventually the connector, in the longitudinal direction. Furthermore, the regulating protrusions provided at both ends have a sufficient distance to each other. Accordingly, the mating connector is regulated the position thereof sufficiently though the regulating protrusion is provided only at two positions. 
     The regulating protrusion of the housing may be provided in the vertical wall portion between the displacement receiving recesses adjacent to each other as well as in the vertical wall portions at both ends of the protruding wall in the longitudinal direction. When the regulating protrusions are provided not only in the vertical wall portion at both end of the protruding wall in the longitudinal direction but also in the vertical wall portion between the displacement receiving recesses adjacent to each other, the mating connector is regulated the position thereof in the short direction more certainly. In addition, by sharing a force for regulating with many regulating positions, it is possible to reduce a stress each regulating protrusion receives. 
     The terminal is formed by bending a metal strip in a thickness direction thereof. It is preferable that the terminal is held in the bottom wall of the housing with the base portion thereof by being molded integrally. In addition, it is preferable that the terminal includes a tapered portion and the tapered portion is held in the bottom wall at a position corresponding thereto. The tapered portion is provided on both edges of the base portion and has a shape being narrower toward the protruding wall. 
     As the connector is connected to the mating connector, the contact portion of the elastic arm portion of the terminal is pushed by the mating terminal of the mating connector and the elastic arm portion is displaced elastically into the displacement receiving recess. Then the base portion receives an external force having a component toward the protruding wall in the short direction of the housing. Since the base portion of the terminal includes the tapered portion, the tapered portion wedges into the bottom wall holding the tapered portion at the position corresponding thereto toward the protruding wall. Thereby, it is possible to prevent the base portion from coming off from the bottom wall. 
     As described above, in the present invention, the transition portion incapable of elastic displacement in the short direction is situated outside the displacement receiving recess. Therefore, the lower mold is able to have the size utilizing the displacement receiving recess entirely in the longitudinal direction. Thereby, it is possible to obtain the lower mold having a simple shape with the sufficient strength. Further, the upper mold is able to have the groove portion corresponding to the elastic arm portion and surrounding the elastic arm portion from three directions without being obstructed by the displacement receiving recess. In addition, the groove portion is able to be larger in size than the space between the inner surface of the displacement receiving recess and the elastic arm portion. Consequently, it is possible to maintain the strength of the upper mold. 
     Further, as opposed to the conventional connector, it is not necessary that the upper mold has the portion corresponding to the space described above. Therefore, it is not necessary to enlarge the upper mold in the longitudinal direction in order to obtain the sufficient strength. Furthermore, it is not necessary to shrink the vertical wall portion in the longitudinal direction. As a result, the housing is able to obtain a sufficient strength. In addition, it is not necessary to enlarge the mold and the housing in the longitudinal direction in order to obtain sufficient strength. Therefore, it is possible to avoid the connector from growing in size. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing an electrical connector with a cross sectional surface perpendicular to a longitudinal direction thereof, according to a first embodiment of the present invention; 
         FIG. 2  is a sectional view showing the electrical connector in  FIG. 1  and a mating connector with the same cross sectional surface in  FIG. 1 ; 
         FIG. 3  is a sectional view partially showing the electrical connector in  FIG. 1  taken along a surface perpendicular to a short direction thereof; 
         FIG. 4  is an enlarged sectional view partially showing the electrical connector in  FIG. 1  around a protruding wall  12  thereof from an upper direction; 
         FIGS. 5(A) and 5(B)  are sectional views showing a state when molds are placed so that a terminal and a housing are molded integrally, wherein  FIG. 5(A)  is the sectional view taken where the terminal is situated and  FIG. 5(B)  is the sectional view taken where a regulating protrusion of the housing is situated; and 
         FIG. 6  is an enlarged sectional view partially showing an electrical connector around a protruding wall  12  thereof from an upper direction, according to a second embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereunder, embodiments of the present invention will be explained with reference to the accompanying drawings. 
     First Embodiment 
     [Configuration of Connector] 
       FIG. 1  is a perspective view showing an electrical connector with a cross sectional surface perpendicular to a longitudinal direction thereof according to a first embodiment.  FIG. 2  is a sectional view showing the electrical connector in  FIG. 1  and a mating connector unconnected to the connector.  FIG. 3  is a sectional view showing the electrical connector in  FIG. 1  taken along a surface perpendicular to a short direction thereof and where a base portion of a terminal is situated. And  FIG. 4  is an enlarged sectional view showing the electrical connector in  FIG. 1  around a protruding wall  12  thereof from an upper direction. 
     The electrical connector  1  (the connector  1 ) according to the embodiment is mounted on a circuit board (not shown) and receives the mating connector  2  to be connected from the upper direction. The connector  1  includes a housing  10  and a plurality of the terminals  20 . The plurality of the terminals  20  are made from metal and disposed to be held in the housing  10  in a longitudinal direction of the housing  10 . 
     As shown in  FIG. 1 , the housing  10  includes a bottom wall  11 , a protruding wall  12  and a circumferential wall surrounding the protruding wall  12 . The bottom wall  11  faces a mounting surface of the circuit board and extends in the longitudinal direction, in other words, a terminal disposing direction. The protruding wall  12  protrudes from the bottom wall  11  in the upper direction and extends in the longitudinal direction. The circumferential wall includes a pair of sidewalls  13  facing each other and extending in the longitudinal direction and a pair of end walls  14 . The end wall  14  connects to end portions of the two sidewalls  13  and extends in the short direction which is perpendicular to the longitudinal direction. The circumferential wall and protruding wall  12  forms a receptacle recess portion  15  having an annular rectangle shape for receiving a fitting portion of the mating connector  2 . 
     The protruding wall  12  includes a plurality of vertical wall portions  12 C. The vertical wall portion  12 C is arranged with an equal interval in the longitudinal direction on a surface of the protruding wall  12  facing an inner wall surface of the sidewall  13 . The vertical wall portion  12 C extends in a vertical direction. The protruding wall  12  forms a displacement receiving recess  12 A next to the vertical wall portions  12 C. The displacement receiving recess  12 A has a recessed shape from the vertical wall portion  12 C and receives an elastic displacement of an elastic arm portion  22  of a terminal  20 , as described later. 
     As shown in  FIGS. 1 and 2 , the displacement receiving recess  12 C is formed on both side surface of the protruding wall  12 . The displacement receiving recess  12 C on each of the side surfaces is separated in the short direction (a horizontal direction in  FIG. 2 ) by a separating wall portion  12 B at an upper portion thereof. The separating wall portion  12 B extends from an upper end of the protruding wall  12  in a lower direction. The displacement receiving recess  12 A opens in a groove-like shape in an upper portion of the protruding wall  12  and conjoins in the short direction in a lower portion thereof. 
     As shown in  FIGS. 3 and 4 , an inner width of the displacement receiving recess  12 A (L 1  in  FIG. 4 ) is wider than a width of the elastic arm portion  22  of the terminal  22  (L 2  in  FIG. 4 ). Therefore, the elastic arm portion  22  is allowed to be easily displaced elastically toward the displacement receiving recess  12 A in the short direction. 
     As shown in  FIGS. 1 ,  3  and  4 , the vertical wall portion  12 C has facing surfaces facing each other, being parallel to each other and perpendicular to the longitudinal direction. The facing surfaces of the vertical wall portion  12 C and a side surface of the separating wall portion  12 B form groove-like shape in the upper portion of the displacement receiving recess  12 A. 
     The protruding wall  12  includes a regulating protrusion  12 D. The regulating protrusion  12 D protrudes from the vertical wall portion  12 C and extends in the vertical direction. As shown in  FIGS. 3 and 4 , the regulating protrusion  12 D has a width (L 3  in  FIG. 4 ) narrower than a width of the vertical wall portion  12 C (L 4  in  FIG. 4 ). A projecting portion of the regulating protrusion  12 D abuts against the fitting portion of the mating connector  2  in the short direction of the housing  10  as the connector  1  connects to the mating connector  2 . Therefore, the regulating protrusion  12 D regulates a position of the mating connector  2  in the short direction. As a result, it is possible to prevent the elastic arm portion  22  of the terminal  20  from being damaged, due to displacement thereof caused by being pressed excessively by a mating terminal  40 . 
     Further, in the embodiment, the regulating protrusion  12 D is situated between the elastic arm portions  22  of the terminals  20  next to each other. Accordingly, it is possible to prevent the elastic arm portions  22  of the terminals  20  next to each other from contacting with each other by being deformed, even though the mating connector  2  is twisted in the longitudinal direction inadvertently as the mating connector  2  is extracted. 
     In addition, as shown in  FIGS. 1 and 3 , an upper end of the regulating protrusion  12 D is situated upper than an upper end of the elastic arm portion  22 . Therefore, when the mating connector  2  is placed irregularly in the short direction as the connector  1  is connected to the mating connector  2 , the mating connector  2  abuts against the upper end of the regulating protrusion  12 D first. Accordingly, it is possible to prevent the elastic arm portion  22  from being damaged by being buckled and the like, due to an abutment by the mating connector  2  to the upper end of the elastic arm portion  22  as the connector  1  is connected to the mating connector  2 . 
     As shown in  FIGS. 1 and 2 , a hole opening  11 A is formed so as to penetrate the bottom wall  11 . The hole opening  11 A is opened where the terminal  20  is situated in the longitudinal direction in the bottom wall  11 . As described later, the hole opening  11 A allows a lower mold P 1  (refer to  FIGS. 5(A) and 5(B) ) to be extracted in the lower direction after an injected resin is solidified as the housing  10  and the terminal  20  are molded integrally. The hole opening  11 A is formed in a central portion of the housing  10  in the short direction and in a region where the protruding wall  12  is included. The hole opening  11 A communicates with the displacement receiving recess  12 A. In the embodiment, the hole opening  11 A is formed in the region where the protruding wall  12  is included. The hole opening  11 A may be formed at least where corresponding to the displacement receiving recess  12 A in the short direction. 
     As shown in  FIGS. 1 and 2 , the sidewall  13  includes a main sidewall  13 A and a secondary sidewall  13 B. The main sidewall  13 A is a main portion of the sidewall  13  extending in the longitudinal direction and in the vertical direction. The secondary sidewall  13 B extends in the longitudinal direction along an outer surface of the main sidewall  13 A and protrudes outward from the main wall portion  13 A. As described later, the main sidewall  13 A holds an entire portion of a held portion  21  having an upside-down U-shape of the terminal  20 . Further, the secondary sidewall  13 B holds the held portion  21  at a portion thereof situated outside. 
     The terminal  20  is formed by bending a metal strip in a thickness direction thereof into an approximate S-shape. The terminals  20  are arranged in the housing  10  forming two rows so as to be symmetrical about the protruding wall  12 . The terminal  20  includes the held portion  21 , the elastic arm portion  22 , the base portion  23  and a connecting portion  24 . The held portion  21  has the upside-down U-shape and is held by the sidewall  13  of the housing  10 . The elastic arm portion  22  extends in the vertical direction at a position close to the protruding wall  12  in the short direction and includes a free end. The base portion  23  is held by the bottom wall  11  of the housing  10 . Further, the base portion  23  extends in the short direction and connects one leg portion of the held portion  21  (an inner leg portion  21 A, described later) to the elastic arm portion  22 . The connecting portion  24  extends from another leg portion of the held portion  21  (an outer leg portion  21 B, described later) to outside the housing  10 . The connecting portion  24  is soldered to a corresponding circuit portion on the circuit board (not shown). As shown in  FIGS. 1 and 2 , the terminal  20  is held by being molded integrally with the housing  10  at the held portion  21  and the base portion  23  thereof. 
     In the embodiment, the terminal is held by the sidewall and the bottom wall of the housing. Configurations of holding the terminal are not limited to the case described above. For example, the terminal may be held by the bottom wall only when the connector does not have the sidewall. 
     The elastic arm portion  22  extends in the upper direction along the protruding wall  12  thorough a transition portion  25  made by being bent. The elastic arm portion  22  is capable of elastic displacement in the short direction by being bent in the thickness direction thereof. The elastic arm portion  22  includes a contact portion  22 A having a convex curved shape toward the sidewall  13  at the free end portion of an upper end portion thereof. As described later, the contact portion  22 A contacts with the mating terminal  40  of the mating connector  2 . As shown in  FIG. 2 , when the elastic arm portion  22  is in a free state, the elastic arm portion  22  and the transition portion  25  are situated outside the displacement receiving recess  12 A of the housing  10 . Further, the contact portion  22 A protrudes from the regulating protrusion  12 D of the housing  10  at a top of the convex curved portion thereof. 
     As shown in  FIG. 2 , the held portion  21  has the upside-down U-shape as described above and includes the inner leg portion  21 A and the outer leg portion  21 B. The inner leg portion  21 A extends along an inner surface of the main sidewall  13 A and the outer leg portion  21 B extends along an outer surface of the main sidewall  13 A. The inner leg portion  21 A includes a locking portion  21 A- 1  at a position close to an upper end thereof. The locking piece  21 A- 1  protrudes into the receptacle recess portion  15  so as to face the contact portion  22 A. 
     As shown in  FIG. 1 , the locking portion  21 A- 1  is provided, for example, by embossment and the like. The locking portion  21 A- 1  has a width narrower than a width of the inner leg portion  21 A. The locking portion  21 A- 1  keeps the connector  1  and the mating connector  2  connected to each other by engaging a locked portion  41 B- 1  of the mating terminal  40  of the mating connector  2 , as well as helping the contact portion  22 A by contacting and conducting electrically with the locked portion  41 B- 1 . 
     As shown in  FIGS. 1 and 2 , the held portion  21  is held over the main sidewall  13 A by being molded integrally. The held portion  21  contacts with the main sidewall  13 A at an inner surface and side edges thereof. An outer surface of the held portion  21  being exposed from the main sidewall  13 A is situated so as to form one smooth surface with an outer surface of the main sidewall  13 A. The held portion  21  is also held in the sidewall  13  as the main sidewall  13 A and the secondary sidewall  13 B sandwich the outer leg portion  21 B thereof. 
     As shown in  FIG. 1 , the base portion  23  includes a tapered portion  23 A protruding from both end edges thereof and having a shape being narrower toward the protruding wall  12 . The tapered portion  23 A is situated at a middle portion of the base portion  23  in the short direction. The base portion  23  is held in the bottom wall  11  of the housing  10 . An upper surface of the base portion  23  is situated in the same height with an upper surface of the bottom wall  11 . Further, the base portion  23  exposes the upper surface thereof in the receptacle recess portion  15 . The connecting portion  24 , as shown in  FIGS. 1 and 2 , is situated in the same height with a lower surface of the bottom wall  11  and capable of being soldered to the corresponding circuit portion on the circuit board. 
     As shown in  FIG. 4 , as described above, the inner width of the displacement receiving recess  12 A in the longitudinal direction (L 1 ) is wider than the width of the elastic arm portion  22  of the terminal  22  (L 2 ). In addition, the regulating protrusion  12 D has the width (L 3 ) narrower than the width of the vertical wall portion  12 C (L 4 ) in the longitudinal direction. Therefore, a distance between two regulating protrusions next to each other in the longitudinal direction (L 5 ) is longer than L 1 . Accordingly, a distance between the elastic arm portion  22  and regulating protrusion  12 D (L 6 ) is longer than a distance between the elastic arm portion  22  and an inner wall surface of the displacement receiving recess  12 A (L 7 ) in the longitudinal direction. 
     [Manufacturing Process of Connector] 
     The connector  1  is manufactured as following.  FIGS. 5(A) and 5(B)  are sectional views showing a state when molds are placed so that the terminal  20  and the housing  10  are molded integrally, wherein  FIG. 5(A)  is the sectional view taken where the terminal  20  is situated and  FIG. 5(B)  is the sectional view taken where a regulating protrusion  12 D is situated. 
     First, as shown in  FIGS. 5(A) and 5(B) , the terminal  20  is arranged on a predetermined position of the lower mold P 1  so as to be symmetrical in the short direction (a horizontal direction in  FIGS. 5(A) and 5(B) ) of the housing  10 . Then an upper mold P 2  and a side mold P 3  are placed from the upper direction and a side direction (a right side or a left side in FIGS.  5 (A) and  5 (B)), respectively. The upper mold P 2 , the side mold P 3  and the lower mold P 1  are placed so as to surround the terminal  20 . Next, the housing  10  is formed by solidifying the resin injected in a liquid form and filled up into a space between the molds through an inlet (not shown). As a result, the housing  10  and the terminal  20  are molded integrally and thereby manufacturing of the connector  1  is completed. After the connector  1  is manufactured, the lower mold P 1  is extracted in the lower direction through the hole opening  11 A of the bottom wall  11  of the housing  10 . The upper mold P 2  and the side mold P 3  are extracted in the upper direction and the side direction, respectively. 
     The lower mold P 1  and the upper mold P 2  mainly form the bottom wall  11 , the protruding wall  12  and the main sidewall  13 A. The side mold P 3  mainly forms the secondary sidewall  13 B. As shown in  FIG. 5(A) , the lower mold P 1  includes a base portion P 1 A having a plate-like shape and a projecting portion P 1 B projecting from the base portion P 1 A. The projecting portion P 1 B is situated in a middle portion of the base portion P 1 A in the short direction (the horizontal direction in  FIG. 5(A) ). The projecting portion P 1 B opens a space including the displacement receiving recess  12 A in the protruding wall  12 . Therefore, the projecting portion P 1 B has a width (in other words, a size thereof in a direction perpendicular to a sheet surface of  FIG. 5(A) ) same as the width of the displacement receiving recess  12 A. The lower mold P 1  further includes a recessed portion P 1 C in an upper portion of projecting portion P 1 B. The recessed portion P 1 C corresponds to the separating wall portion  12 B of the protruding wall  12 . 
     As shown in  FIGS. 5(A) and 5(B) , the upper mold P 2  includes a frame-like portion corresponding to the receptacle recess portion  15 . The frame-like portion includes a wall portion P 2 A extends in the longitudinal direction. Further, the upper mold P 2  includes a recessed portion P 2 B corresponding to the protruding wall  12 . The recessed portion P 2 B is provided between the two wall portions P 2 A. 
     Further, as shown in  FIG. 5(A) , the wall portion P 2 A includes an inner groove portion P 2 C and an outer groove portion P 2 D in an inner surface thereof and an outer surface thereof, respectively. The inner groove portion P 2 C and the outer groove portion P 2 D are situated at positions corresponding to the terminal  20  in the longitudinal direction. The inner groove portion P 2 C is recessed so as to correspond to the elastic arm portion  22  and the transition portion  25  of the terminal  20 . The outer groove portion P 2 D is recessed so as to correspond to the inner leg portion  21 A of the held portion  21 . The inner groove portion P 2 C opens toward the protruding wall  12  and surrounds the elastic arm portion  22  from other three directions upon being molded integrally. The outer groove portion P 2 D opens toward an opposite direction of the protruding wall  12  and surrounds the inner leg portion  21 A of the held portion  21  from other three directions upon being molded integrally. 
     As shown in  FIG. 5(A) , the side mold P 3  includes a recessed portion P 3 A at a position corresponding to the terminal  20  in the side surface thereof in the longitudinal direction. The recessed portion P 3 A is recessed so as to correspond to the held portion  21  of the terminal  20 . The recessed portion P 3 A is recessed further so as to correspond to the secondary sidewall  13 B in a range of the sidewall  13  in the longitudinal direction. 
     As shown in  FIG. 2 , according to the embodiment, the elastic arm portion  22  and the transition portion  25  of the terminal  20  of the connector  1  are not situated in the displacement receiving recess  12 A. Therefore, an entire region of the width of the displacement receiving recess  12 A is able to use for the lower mold P 1 . Therefore, the displacement receiving recess  12 A is formed by placing the lower mold P 1  with the projecting portion P 1 B being formed with a width of the entire region of the width of the displacement receiving recess  12 A (L 1  in  FIG. 4 ) from the lower direction. Consequently, it is possible to obtain the lower mold P 1  having a sufficient size (width) and strength. 
     According to the embodiment, the elastic arm portion  22  and the transition portion  25  of the terminal  20  of the connector  1  are not situated in the displacement receiving recess  12 A. When only the transition portion  25  is not situated in the displacement receiving recess  12 A, in other words, the elastic arm portion  22  is in the free state and situated in the displacement receiving recess  12 A, it is also possible to manufacture the connector using the molds P 1  and P 3 . 
     Accordingly, when the elastic arm portion  22  is in the free state and situated in the displacement receiving recess  12 A, the lower mold P 1  provided from the lower direction displaces the elastic arm portion  22  elastically toward outside the displacement receiving recess  12 A upon being molded integrally. As a result, the elastic arm portion  22  allows the lower mold P 1  to be placed. Therefore, the lower mold P 1  can be placed when the transition portion  25  is not situated in the displacement receiving recess  12 A regardless where the elastic arm portion  22  is situated. 
     Further, in the embodiment, the elastic arm portion  22  is not situated in the displacement receiving recess  12 A, in other words, the elastic arm portion  22  is situated in the receptacle recess portion  15 . Therefore, the upper mold P 2  is able to have the inner groove portion P 2 C corresponding to the elastic arm portion  22  with a shape surrounding the elastic arm portion  22  from three sides and having an opening toward the protruding wall  12 . As a result, the upper mold P 2  is able to have a simple shape. 
     Furthermore, in the embodiment, the elastic arm portion  22  is not situated in the displacement receiving recess  12 A. Accordingly, unlike the conventional connectors, the elastic arm portion  22  is situated in an open space without being surrounded by the inner wall surfaces of the displacement receiving recess. Therefore, the inner groove portion P 2 C of the upper mold P 2  is able to have a width (L 6  in  FIG. 4 ) larger than the distance between the elastic arm portion  22  and an inner wall surface of the displacement receiving recess  12 A (L 7  in  FIG. 4 ). As a result, it is possible to obtain the upper mold P 2  having a simple shape and sufficient strength. 
     In addition, in the embodiment, the upper mold P 2  does not need to have a portion corresponding to the distance described above unlike the conventional connectors. Therefore, it is not necessary to narrow the width of the vertical wall portion  12 C in the longitudinal direction as it is not necessary for the portion described above of the upper mold P 2  to be wide enough in order to obtain sufficient strength. As a result, it is possible to maintain strength of the vertical wall portion  12 C. Further, it is possible to prevent the connector  1  from being larger, since the molds and the housing  10  are able to obtain sufficient strength without being larger in the longitudinal direction. 
     [Configuration of Mating Connector] 
     The mating connector  2  shown in  FIG. 2  is attached to a circuit board (not shown). The mating connector  2  includes the fitting portion having a frame-like shape and corresponding to the receptacle recess portion  15  of the connector  1 . The mating connector  2  is connected to the connector  1  as the fitting portion is fitted into the receptacle recess portion  15 . As shown in  FIG. 2 , the mating connector  2  includes a housing  30  and a plurality of terminals  40  (mating terminals  40 ). The housing  30  has a substantial rectangular parallelepiped shape and made from a synthetic resin. The mating terminal  40  is arranged and held in the housing  30  in the longitudinal direction of the housing  30  by being molded integrally. 
     The housing  30  includes a bottom wall  31  facing the circuit board and a circumferential wall rising from the bottom wall  31 . The mating connector  2  further includes a receptacle recess portion  35  surrounded by the bottom wall  31  and the circumferential wall. The receptacle recess portion  35  has an opening toward the lower direction as shown in  FIG. 2 . Upon being connected to the connector  1 , the receptacle recess portion  35  receives the protruding wall  12  of the housing  10  of the connector  1  therein. The circumferential wall includes a pair of sidewalls  33  facing each other and extending in the longitudinal direction. The mating terminal  40  is disposed and held in the sidewall  33 . 
     The mating terminal  40  is made by bending a metal strip in a thickness direction thereof and held in the housing  30  being arranged in two rows in a short direction (a horizontal direction in  FIG. 2 ) of the housing  30  so as to be symmetrical. The mating terminal  40  includes an engaging portion  41 , an inner leg portion  41 A, a transition portion  45  and a connecting portion  44 . The engaging portion  41  has a U-shape and the inner leg portion  41 A is one of two leg portions of the engaging portion  41  situated closer to the receptacle recess portion  35 . The connecting portion  44  extends in the short direction from the transition portion  45  being formed by being bent. The connecting portion  44  is soldered to a corresponding circuit portion of the circuit board. As shown in  FIG. 2 , the mating terminal  40  is held in the housing  30  by being molded integrally with the engaging portion  41  and the transition portion  44  thereof. 
     The engaging portion  41  is buried in the sidewall  33  so as to stride over the sidewall  33  from the lower direction. The sidewall  33  holds side edges and an inner surface of the engaging portion  41 . An outer surface of the engaging portion  41  exposing from the sidewall  33  forms a smooth surface with an outer plate surface of the sidewall  33 . The engaging portion  41  has a slightly larger size in the short direction (the horizontal direction in  FIG. 2 ) than a distance between the contact portion  22  and the locking portion  12 A- 1  of the terminal  20  of the connector  1 . 
     The engaging portion  41  includes a corresponding contact portion  41 A- 1  on the outer plate surface closer to the receptacle recess portion  35  of the inner leg portion  41 A thereof. The corresponding contact portion  41 A- 1  is provided at a position closer to the bottom wall  31 . The corresponding contact portion  41 A- 1  contacts with the contact portion  22 A of the terminal  20  of the connector  1  with contact pressure, as the connector  1  and the mating connector  2  are connected to each other. The engaging portion  41  further includes the locked portion  41 B- 1  with a recessed shape provided at a position closer to the bottom wall  31  (an upper side in  FIG. 2 ) on an outer surface of an outer leg portion  41 B. The outer leg portion  41 B is one of the two leg portions of the engaging portion  41  situated distant to the receptacle recess portion  35 . The locked portion  41 B engages the locking portion  21 A- 1  of the terminal  20 . 
     As shown  FIG. 2 , the connecting portion  44  is situated approximately in the same height with a lower surface (an upper surface in  FIG. 2 ) of the bottom wall  31 . The connecting portion  44  is capable of being soldered to the corresponding circuit portion of the circuit board. 
     [Manufacturing Process of Mating Connector] 
     The mating connector  2  is manufactured by molding the housing  30  and the mating terminal  40  integrally using an upper mold and a lower mold (not shown). The upper mold and the lower mold are different molds from the molds used for molding the connector  1 . 
     [Connection of Connectors] 
     Hereunder, operation for connection of the connector  1  and the mating connector  2  will be explained. First, the connector  1  and the mating connector  2  are soldered to the corresponding circuit portions of the circuit boards, respectively. Next, as shown in  FIG. 2 , the connector  1  is placed so that the receptacle recess portion  15  thereof opens toward the upper direction and the mating connector  2  is placed over the connector  1  so that the receptacle recess portion  35  thereof opens toward the lower direction. Next, the mating connector  2  is moved in the lower direction to insert the fitting portion of the mating connector  2  into the receptacle recess portion  15  of the connector  1 . 
     Accordingly, the engaging portion  41  of the mating terminal  40  of the mating connector  2  moves pushing to open a space between the contact portion  22 A and the locking portion  21 A- 1  of the terminal  20  of the connector  1 . Then the elastic arm portion  22  is displaced elastically into the displacement receiving recess  12 A as the contact portion  22 A is pushed into the displacement receiving recess  12 A. As the engaging portion  41  moves further, the contact portion  22 A contacts with the corresponding contact portion  41 A- 1  of the engaging portion  41  with the contact pressure and the locking portion  21 A- 1  engages the locked portion  41 B- 1  of the engaging portion  41  in the vertical direction. Consequently, the terminals of the connectors are conducted electrically with each other as well as locking each other. Thereby, the operation for connection of the connectors is completed. 
     When the elastic arm portion  22  of the terminal  20  of the connector  1  is displaced in the displacement receiving recess  12 A toward the protruding wall  12  as the connectors are connected to each other, the base portion  23  of the terminal  20  receives an external force having a component toward the protruding wall  12  in the short direction of the housing  10 . As a result, the tapered portion  23 A of the base portion  23  wedges toward the protruding wall  12  into a corresponding portion of the bottom wall  11  holding the tapered portion  23 A. Thereby, it is possible to prevent the base portion  23  from coming off from the bottom wall  11 . 
     In the embodiment, an upper surface of the tapered portion is situated in the same height with the upper surface of the bottom wall and exposed in the receptacle recess portion. The tapered portion may be buried entirely in the bottom wall without exposing the upper surface thereof. For example, the tapered portion may be buried entirely by having a downward slope from the side edge of the base portion, in other words, in a direction the tapered portion protrudes. Accordingly, the corresponding portion of the bottom wall blocks the tapered portion from moving in the upper direction by burying the tapered portion entirely in the bottom wall. As a result, it is possible to improve an effect of preventing the terminal from coming off, since the base portion does not come off from the bottom wall more certainly. 
     Second Embodiment 
     In a second embodiment of the present invention, the facing surfaces of the displacement receiving recess are not parallel to each other, while the facing surfaces are parallel to each other in the first embodiment. The facing surfaces are configured so as to be apart from each other toward the receptacle recess portion, in other words, toward the opening of the displacement receiving recess. In the embodiment, the configuration being different from the first embodiment will be explained mainly. Components similar to the first embodiment are designated with the same numeral references and explanations thereof will be omitted. 
       FIG. 6  is an enlarged sectional view showing the protruding wall  12  of the connector and a neighborhood thereof from an upper direction, according to the embodiment. 
     As shown in  FIG. 6 , in the embodiment, the facing surfaces of the displacement receiving recess  12 A are apart from each other toward the receptacle recess portion  15  (refer to  FIGS. 1 and 2 ) and have a tapered shape. According to having tapered facing surfaces as described above, it is possible to be easier to extract the lower mold from the displacement receiving recess  12 A in the lower direction after the housing  10  and terminal  20  are molded integrally in the process of manufacturing the connector as compared to a case of the first embodiment having the facing surfaces parallel to each other. 
     Further, a distance between the facing surfaces is not steady in the short direction (a vertical direction in  FIG. 6 ). Therefore, the lower mold is able to be made easier as compared to a case of having the facing surfaces parallel to each other, since it allows the lower mold to have an error in size to some extent at a portion thereof corresponding to the displacement receiving recess  12 A. 
     Variation 
     In the first and the second embodiments of the present invention, each of the vertical wall portions of the protruding wall has the regulating protrusion. When the regulating protrusion has enough strength, it is not necessary to provide the regulating protrusion in every vertical wall portion. Arbitrary two or more of the vertical wall portions may include the regulating protrusions, respectively. As described above, it is also possible to regulate positioning of the mating connector satisfactorily when the regulating protrusions are provided in two or more the vertical wall portions. 
     In addition, it is possible to provide the regulating protrusion in the vertical wall portion situated at an end of the protruding wall in the longitudinal direction without providing the regulating protrusion in the vertical wall portion situated between the displacement receiving recesses adjacent to each other. As a result, it is possible to downsize the vertical wall portion not having the regulating protrusion in the longitudinal direction by not making the regulating protrusions. Consequently, it is possible to downsize the housing, eventually the connector, in the longitudinal direction. 
     The disclosure of Japanese Patent Application No. 2011-019581 filed on Feb. 1, 2011, is incorporated in the application by reference. 
     While the invention has been explained with reference to the specific embodiments of the invention, the explanation is illustrative and the invention is limited only by the appended claims.