Patent Publication Number: US-11398697-B2

Title: Connector and connector manufacturing method

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a connector, particularly to a connector mounted on a mounting object and connected to a counter connector. 
     The present invention also relates to a method of manufacturing such a connector. 
     As a connector having a large number of contacts, for example, JP 2017-84736 A discloses a receptacle connector  1  and a plug connector  2  both of which have a substantially flat plate shape, as shown in  FIG. 27 . 
     The receptacle connector  1  has a plurality of receptacle contacts  4  press-fitted in and retained by a receptacle housing  3  of flat plate shape, and the plug connector  2  has a plurality of plug contacts  6  press-fitted in and retained by a plug housing  5  of flat plate shape. The receptacle contacts  4  form four contact arrays  7  linearly extending in parallel to each other, and the plug contacts  6  form four contact arrays  8  linearly extending in parallel to each other so as to correspond to the four contact arrays  7  of the receptacle connector  1 . 
     When the plug connector  2  is fitted to the receptacle connector  1 , as shown in  FIG. 28 , the plug contacts  6  forming the four contact arrays  8  are connected to the receptacle contacts  4  forming the four contact arrays  7  correspondingly, thus making a connector assembly.  FIG. 28  is a cross-sectional view cut along a plane orthogonal to the direction in which the contact arrays  7  and  8  extend. 
     In manufacture of the receptacle connector  1 , since each contact array  7  has plural receptacle contacts  4 , receptacle contacts  4  constituting one contact array  7  can be press-fitted together into the receptacle housing  3  while being joined to a single carrier, and then, the carrier can be separated from the receptacle contacts  4  at a time by means of a carrier cutting tool. Thus, a step involving collective press-fitting of plural receptacle contacts  4  joined to a carrier and collective separation thereof is repeated four times to manufacture the receptacle connector  1  having the four contact arrays  7 . 
     Also for the plug connector  2 , on the basis of each contact array  8 , collective press-fitting of plural plug contacts  6  joined to a carrier and collective separation thereof are serially carried out, thus manufacturing the plug connector  2  having the four contact arrays  8  in the same manner as that for the receptacle connector  1 . 
     As shown in  FIG. 28 , however, in the receptacle connector  1  of JP 2017-84736 A, the receptacle contacts  4  constituting the four contact arrays  7  are disposed to coincide each other in the direction perpendicular to the contact arrays  7 ; similarly, in the plug connector  2 , the plug contacts  6  constituting the four contact arrays  8  are disposed to coincide each other in the direction perpendicular to the contact arrays  8 . 
     Therefore, in manufacture of the receptacle connector  1 , it is difficult to join plural receptacle contacts  4  of plural contact arrays  7 , e.g., two contact arrays  7  adjacent to each other to a single carrier, and accordingly, press-fitting and separation of the plural receptacle contacts  4  need to be carried out using separate carriers for the respective contact arrays  7 . Similarly, also in manufacture of the plug connector  2 , it is difficult to join plural plug contacts  6  of plural contact arrays  8  to a single carrier, and accordingly, press-fitting and separation of the plural plug contacts  6  need to be carried out using separate carriers for the respective contact arrays  8 . 
     Thus, many steps are required to manufacture the receptacle connector  1  and the plug connector  2 , disadvantageously. 
     SUMMARY OF THE INVENTION 
     The present invention has been made to solve the conventional problem described above and is aimed at providing a connector that allows facilitation of its manufacturing process despite that the connector has a large number of contacts. 
     The present invention is also aimed at providing a method of manufacturing such a connector. 
     A connector according to the present invention is a connector mounted on a mounting object and connected to a counter connector, the connector comprising: 
     a housing; and 
     a plurality of contacts retained by the housing, 
     wherein the plurality of contacts form a plurality of contact arrays that linearly extend in a predetermined array direction in parallel to each other, 
     wherein each of the plurality of contacts has a mounting portion that is fixed to the mounting object when the connector is mounted on the mounting object and a contact portion that contacts a corresponding contact of the counter connector when the connector is connected to the counter connector, 
     wherein the mounting portions of contacts constituting at least two contact arrays adjacent to each other of the plurality of contact arrays extend in a same elongation direction, and 
     wherein contacts constituting each contact array of the at least two contact arrays are disposed in a position other than a position where those contacts completely coincide with contacts constituting another contact array of the at least two contact arrays in a direction perpendicular to the predetermined array direction. 
     A method of manufacturing a connector according to the present invention comprises: 
     a step of retaining a plurality of contacts joined to a carrier via corresponding joint portions by a housing; and 
     a step of separating the carrier from the plurality of contacts retained by the housing, 
     wherein the plurality of contacts form a plurality of contact arrays that linearly extend in a predetermined array direction in parallel to each other, 
     wherein the joint portions joined to contacts constituting at least two contact arrays adjacent to each other of the plurality of contact arrays extend in a same elongation direction, and 
     wherein contacts constituting each contact array of the at least two contact arrays are disposed in a position other than a position where those contacts completely coincide with contacts constituting another contact array of the at least two contact arrays in a direction perpendicular to the predetermined array direction. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing a connector assembly composed of a receptacle connector and a plug connector according to an embodiment of the invention, before fitting. 
         FIG. 2  is a perspective view of the receptacle connector, when viewed from an obliquely upper position. 
         FIG. 3  is a perspective view of the receptacle connector, when viewed from an obliquely lower position. 
         FIG. 4  is a plan view showing the receptacle connector. 
         FIG. 5  is an enlarged partial perspective view showing a receptacle housing used in the receptacle connector. 
         FIG. 6  is a plan view showing a connector accommodating groove of the receptacle housing used in the receptacle connector. 
         FIG. 7  is a perspective view showing a receptacle contact used in the receptacle connector. 
         FIG. 8  is an enlarged partial plan view of the receptacle connector. 
         FIG. 9  is a cross-sectional view taken along line A-A in  FIG. 4 . 
         FIG. 10  is a cross-sectional view taken along line B-B in  FIG. 4 . 
         FIG. 11  is a view showing a step of attaching receptacle contacts joined to carriers to the receptacle housing. 
         FIG. 12  is a view showing a step of separating the carriers from the receptacle contacts attached to the receptacle housing. 
         FIG. 13  is a perspective view of the plug connector, when viewed from an obliquely upper position. 
         FIG. 14  is a perspective view of the plug connector, when viewed from an obliquely lower position. 
         FIG. 15  is a plan view showing the plug connector. 
         FIG. 16  is an enlarged partial perspective view showing a plug housing used in the plug connector. 
         FIG. 17  is a perspective view showing a plug contact used in the plug connector. 
         FIG. 18  is an enlarged partial plan view of the plug connector. 
         FIG. 19  is a cross-sectional view taken along line C-C in  FIG. 15 . 
         FIG. 20  is a cross-sectional view taken along line D-D in  FIG. 15 . 
         FIG. 21  is a view showing a step of attaching plug contacts joined to carriers to the plug housing. 
         FIG. 22  is a view showing a step of separating the carriers from the plug contacts attached to the plug housing. 
         FIG. 23  is a perspective view showing the connector assembly in a fitted state. 
         FIG. 24  is a plan view showing the connector assembly in a fitted state. 
         FIG. 25  is a cross-sectional view taken along line E-E in  FIG. 24 . 
         FIG. 26  is a cross-sectional view taken along line F-F in  FIG. 24 . 
         FIG. 27  is a perspective view showing a conventional connector assembly before fitting. 
         FIG. 28  is a cross-sectional view of the conventional connector assembly in a fitted state. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     An embodiment of the present invention is described below with reference to the accompanying drawings. 
       FIG. 1  shows a receptacle connector (connector)  11  and a plug connector (connector)  21  according to the embodiment before the connectors  11  and  21  are fitted to each other. The receptacle connector  11  and the plug connector  21  constitute a connector assembly, each have a substantially rectangular flat plate shape, and are arranged in parallel to each other. 
     The receptacle connector  11  has a receptacle housing (housing)  31  and a plurality of receptacle contacts (contacts)  41  retained by the receptacle housing  31 . The receptacle contacts  41  form four contact arrays S 1  to S 4  linearly extending in a predetermined array direction in parallel to each other. Similarly, the plug connector  21  has a plug housing (housing)  51  and a plurality of plug contacts (contacts)  61  retained by the plug housing  51 . The plug contacts  61  form four contact arrays T 1  to T 4  linearly extending in the same array direction as that of the contact arrays S 1  to S 4  of the receptacle connector  11  in parallel to each other. 
     The contact arrays S 1  to S 4  of the receptacle connector  11  and the contact arrays T 1  to T 4  of the plug connector  21  extend in the same direction. 
     In the state where the receptacle connector  11  and the plug connector  21  are fitted with each other, the receptacle contacts  41  in the contact arrays S 1  to S 4  of the receptacle connector  11  are correspondingly connected to the plug contacts  61  in the contact arrays T 1  to T 4  of the plug connector  21 . 
     For convenience, the plane in which the receptacle connector  11  of substantially flat plate shape extends is called “XY plane,” the predetermined array direction in which the contact arrays S 1  to S 4  of the receptacle connector  11  extend “Y direction,” the direction in which the contact arrays S 1  to S 4  are arranged “X direction,” and the direction perpendicular to an XY plane and from the receptacle connector  11  toward the plug connector  21  “+Z direction.” 
     As with the receptacle connector  11 , the plug connector  21  extends along an XY plane, the contact arrays T 1  to T 4  of the plug connector  21  extend in the Y direction, and the contact arrays T 1  to T 4  are arranged in the X direction. 
     The receptacle connector  11  is able to fit with the plug connector  21  serving as a counter connector, and as shown in  FIGS. 2 to 4 , has a center line C 1  extending in the Y direction. In the receptacle connector  11 , the contact arrays S 1  and S 2  are disposed on the +X direction side of the center line C 1 , and the contact arrays S 3  and S 4  are disposed on the −X direction side of the center line C 1 . 
     The receptacle housing  31  of the receptacle connector  11  is made of an insulating body such as insulating resin, has a substantially flat plate shape, and includes a flat surface portion  32  extending along an XY plane on the −Z side of the receptacle housing  31 . A peripheral wall portion  33  protruding in the +Z direction is formed along the outer periphery of the flat surface portion  32 , and three projecting portions  34  are formed in the area surrounded by the peripheral wall portion  33  and project in the +Z direction from the flat surface portion  32  while extending in the Y direction in parallel to each other. The three projecting portions  34  have the same length in the Y direction, and one projecting portion  34  situated in the middle in the X direction is wider in the X direction than each of the projecting portions  34  situated in the opposite sides in the X direction. 
     The receptacle housing  31  has four contact array retaining portions  35  disposed separately on the +X direction side of, among the three projecting portions  34 , the projecting portion  34  furthest on the +X direction side, on the +X direction side and the −X direction side of the projecting portion  34  situated in the middle in the X direction, and on the −X direction side of the projecting portion  34  furthest on the −X direction side. The four contact array retaining portions  35  extend in the Y direction and separately retain the contact arrays S 1  to S 4 . 
     In the receptacle housing  31 , an opening portion  36 A extending in the Y direction and penetrating the receptacle housing  31  in the Z direction is formed between the contact array retaining portion  35  disposed on the +X direction side of the projecting portion  34  situated in the middle in the X direction and the projecting portion  34  furthest on the +X direction side. Similarly, an opening portion  36 B extending in the Y direction and penetrating the receptacle housing  31  in the Z direction is formed between the contact array retaining portion  35  disposed on the −X direction side of the projecting portion  34  situated in the middle in the X direction and the projecting portion  34  furthest on the −X direction side. 
     Two positioning recess portions  37  are formed in the peripheral wall portion  33  at the +Y directional end of the receptacle housing  31  at a certain interval in the X direction to open in the +Z direction, while one positioning recess portion  37  is formed in the peripheral wall portion  33  at the −Y directional end of the receptacle housing  31  to open in the +Z direction. 
     As shown in  FIG. 5 , each contact array retaining portion  35  has a plurality of contact accommodating grooves  38  aligned in the Y direction. Each contact accommodating groove  38  extends in the X direction and opens in the −Z direction. As shown in  FIG. 6 , the contact accommodating groove  38  is provided in its inside with a pair of projections  38 A that project separately from the inner surfaces on the +Y and −Y direction sides of the contact accommodating groove  38  such that the tips of the projections  38 A face each other. Those projections  38 A and an X directional end of the contact accommodating groove  38  constitute a retaining portion  38 B for retaining the corresponding receptacle contact  41 . 
     As shown in  FIG. 7 , the receptacle contact  41  is formed by bending a band-shaped metal plate having electrical conductivity, and has a mounting portion  41 A at its one end and a contact portion  41 B at its other end. The mounting portion  41 A extends along an XY plane and, when the receptacle connector  11  is mounted onto a mounting object such as a circuit board, is joined and fixed to a connecting pad or the like of the mounting object. Meanwhile, the contact portion  41 B is a spring contact that is elastically displaceable in the X direction and when the receptacle connector  11  is connected to the plug connector  21  serving as the counter connector, comes into contact with the corresponding plug contact  61  of the plug connector  21 . 
     The receptacle contact  41  further has a portion to be retained  41 C between the mounting portion  41 A and the contact portion  41 B. The portion to be retained  41 C has a pair of jutting portions  41 D jutting separately in the +Y direction and the −Y direction from the band-shaped metal plate forming the receptacle contact  41 . By press-fitting the portion to be retained  41 C having the jutting portions  41 D into the retaining portion  38 B of the corresponding contact accommodating groove  38  of the receptacle housing  31  from the −Z direction side, the receptacle contact  41  is retained by the contact accommodating groove  38 . 
     The receptacle contact  41  has a larger width in the Y direction at the pair of jutting portions  41 D than that at the other portions, and the width in the Y direction of the receptacle contact  41  at the pair of jutting portions  41 D is defined as a contact width W 1 . 
     As shown in  FIG. 8 , the receptacle contacts  41  constituting each of the contact arrays S 1  to S 4  are aligned in the Y direction at a predetermined array pitch P 1 , and the adjacent contact arrays S 1  and S 2  are arranged to be offset from each other in the Y direction by an offset amount P 2  equal to a half of the array pitch P 1 . The array pitch P 1  is set to be larger than a double of the contact width W 1  of the receptacle contact  41 . In other words, the offset amount P 2  equal to a half of the array pitch P 1  is set to be larger than the contact width W 1  of the receptacle contact  41 . 
     Accordingly, the receptacle contacts  41  constituting the contact array S 1  and the receptacle contacts  41  constituting the contact array S 2  are arranged to be offset from each other in the Y direction by the offset amount P 2  and do not overlap each other at all in the X direction perpendicular to the Y direction. 
     As can be seen from  FIG. 4 , the adjacent contact arrays S 3  and S 4  are also arranged to be offset from each other in the Y direction by the offset amount P 2 . The receptacle contacts  41  constituting the contact array S 3  and the receptacle contacts  41  constituting the contact array S 4  are arranged to be offset from each other in the Y direction by the offset amount P 2  and do not overlap each other at all in the X direction perpendicular to the Y direction. 
     The contact arrays S 1  and S 4  are disposed at the same position in the Y direction with no offset, and the contact arrays S 2  and S 3  are also disposed at the same position in the Y direction with no offset. 
     Therefore, when the receptacle connector  11  is cut along an XZ plane passing through given receptacle contacts  41  of the contact arrays S 1  and S 4 , as shown in  FIG. 9 , the receptacle contact  41  of the contact array S 1  and the receptacle contact  41  of the contact array S 4  appear in the cross section, whereas for the contact arrays S 2  and S 3 , no receptacle contact  41  appears in the cross section with only a section of the receptacle housing  31  being seen. 
     Similarly, when the receptacle connector  11  is cut along an XZ plane passing through given receptacle contacts  41  of the contact arrays S 2  and S 3 , as shown in  FIG. 10 , the receptacle contact  41  of the contact array S 2  and the receptacle contact  41  of the contact array S 3  appear in the cross section, whereas for the contact arrays S 1  and S 4 , no receptacle contact  41  appears in the cross section with only a section of the receptacle housing  31  being seen. 
     On the +X direction side in the receptacle connector  11 , all of the mounting portions  41 A of the receptacle contacts  41  of the adjacent contact arrays S 1  and S 2  extend in the +X direction, which is an elongation direction, along the flat surface portion  32  of the receptacle housing  31 . All of the mounting portions  41 A of the receptacle contacts  41  of the contact array S 1  protrude in the +X direction from the +X directional end of the receptacle housing  31 , and all of the mounting portions  41 A of the receptacle contacts  41  of the contact array S 2  protrude in the opening portion  36 A of the receptacle housing  31  that is situated on the +X direction side of the contact array S 2 . 
     Similarly, on the −X direction side in the receptacle connector  11 , all of the mounting portions  41 A of the receptacle contacts  41  of the adjacent contact arrays S 3  and S 4  extend in the −X direction, which is an elongation direction, along an XY plane. All of the mounting portions  41 A of the receptacle contacts  41  of the contact array S 3  protrude in the opening portion  36 B of the receptacle housing  31  that is situated on the −X direction side of the contact array S 3 , and all of the mounting portions  41 A of the receptacle contacts  41  of the contact array S 4  protrude in the −X direction from the −X directional end of the receptacle housing  31 . 
     A method of manufacturing the receptacle connector  11  as above is described. As shown in  FIG. 11 , the receptacle contacts  41  constituting the contact array S 1  and the receptacle contacts  41  constituting the contact array S 2  are joined to a single carrier  43 A via associated joint portions  42 , and the receptacle contacts  41  constituting the contact array S 4  and the receptacle contacts  41  constituting the contact array S 3  are joined to another single carrier  43 B via associated joint portions  42 . The joint portions  42  connect the mounting portions  41 A of the respective receptacle contacts  41  to the corresponding carrier  43 A or  43 B. 
     Note that, as shown in  FIG. 8 , the receptacle contacts  41  constituting the contact array S 1  and the receptacle contacts  41  constituting the contact array S 2  are arranged so as not to overlap each other in the X direction. This configuration allows the receptacle contacts  41  constituting the contact array S 1  and the receptacle contacts  41  constituting the contact array S 2  to be joined to the single carrier  43 A. 
     Similarly, the receptacle contacts  41  constituting the contact array S 4  and the receptacle contacts  41  constituting the contact array S 3  are arranged so as not to overlap each other in the X direction. This configuration allows the receptacle contacts  41  constituting the contact array S 4  and the receptacle contacts  41  constituting the contact array S 3  to be joined to the other single carrier  43 B. 
     When the two carriers  43 A and  43 B are moved toward the receptacle housing  31  from the −Z direction side to the +Z direction side, the receptacle contacts  41  of the contact arrays S 1  to S 4  are fitted and accommodated into the corresponding contact accommodating grooves  38  of the receptacle housing  31 . At this time, the portion to be retained  41 C having the pair of jutting portions  41 D shown in  FIG. 7  in each receptacle contact  41  is press-fitted into and retained by the retaining portion  38 B of the corresponding contact accommodating groove  38  shown in  FIG. 6 . 
     Thus, as shown in  FIG. 12 , all of the receptacle contacts  41  of the contact arrays S 1  to S 4  can be press-fitted together into the receptacle housing  31  by means of the two carriers  43 A and  43 B in one step. 
     The joint portions  42  connecting the receptacle contacts  41  of the contact array S 1  to the carrier  43 A extend in the +X direction from the +X directional end of the receptacle housing  31 , and the joint portions  42  connecting the receptacle contacts  41  of the contact array S 2  to the carrier  43 A extend across the opening portion  36 A of the receptacle housing  31  that is situated on the +X direction side of the contact array S 2  and further extend in the +X direction from the +X directional end of the receptacle housing  31 . 
     In contrast, the joint portions  42  connecting the receptacle contacts  41  of the contact array S 4  to the carrier  43 B extend from the −X directional end of the receptacle housing  31  toward the −X direction, and the joint portions  42  connecting the receptacle contacts  41  of the contact array S 3  to the carrier  43 B extend across the opening portion  36 B of the receptacle housing  31  that is situated on the −X direction side of the contact array S 3  and further extend from the −X directional end of the receptacle housing  31  toward the −X direction. 
     Next, as shown in  FIG. 12 , the receptacle contacts  41  are separated from the two carriers  43 A and  43 B by means of four carrier separating tools  44 . Each of the four carrier separating tools  44  is a plate member extending along a YZ plane and is provided at its −Z directional end with a blade portion extending along the Y direction. The four carrier separating tools  44  are arranged at intervals in the X direction. 
     Of the four carrier separating tools  44 , the carrier separating tool  44  situated furthest on the +X direction side is disposed slightly away from the +X directional end of the receptacle housing  31  in the +X direction, and the carrier separating tool  44  situated furthest on the −X direction side is disposed slightly away from the −X directional end of the receptacle housing  31  in the −X direction. 
     Further, of the four carrier separating tools  44 , the carrier separating tool  44  that is the second from the end on the +X direction side is disposed at a position corresponding to the opening portion  36 A of the receptacle housing  31  that is situated on the +X direction side of the contact array S 2 , and the carrier separating tool  44  that is the second from the end on the −X direction side is disposed at a position corresponding to the opening portion  36 B of the receptacle housing  31  that is situated on the −X direction side of the contact array S 3 . 
     The four carrier separating tools  44  as above are moved from the +Z direction side toward the −Z direction side, and the blade portions at the −Z directional ends of the carrier separating tools  44  are each pressed to the joint portions  42  of the corresponding carrier  43 A or  43 B; as a result, the joint portions  42  are cut, and the receptacle contacts  41  are separated from the carrier  43 A or  43 B. 
     In this process, of the four carrier separating tools  44 , the carrier separating tool  44  situated furthest on the +X direction side is moved in the −Z direction along a course slightly away from the +X directional end of the receptacle housing  31  in the +X direction, whereby the receptacle contacts  41  of the contact array S 1  are separated from the carrier  43 A, and the carrier separating tool  44  that is the second from the end on the +X direction side is moved in the −Z direction through the opening portion  36 A of the receptacle housing  31 , whereby the receptacle contacts  41  of the contact array S 2  are separated from the carrier  43 A. 
     Since the receptacle contacts  41  of the contact array S 1  and the receptacle contacts  41  of the contact array S 2  are joined to the carrier  43 A situated on the +X direction side of the receptacle housing  31  via the corresponding joint portions  42 , once the joint portions  42  are cut, consequently, the mounting portions  41 A of the receptacle contacts  41  of the contact array S 1  all extend in the +X direction so as to protrude from the +X directional end of the receptacle housing  31 , and the mounting portions  41 A of the receptacle contacts  41  of the contact array S 2  all extend in the +X direction so as to protrude in the opening portion  36 A of the receptacle housing  31 . 
     Further, of the four carrier separating tools  44 , the carrier separating tool  44  situated furthest on the −X direction side is moved in the −Z direction along a course slightly away from the −X directional end of the receptacle housing  31  in the −X direction, whereby the receptacle contacts  41  of the contact array S 4  are separated from the carrier  43 B, and the carrier separating tool  44  that is the second from the end on the −X direction side is moved in the −Z direction through the opening portion  36 B of the receptacle housing  31  that is situated on the −X direction side of the contact array S 3 , whereby the receptacle contacts  41  of the contact array S 3  are separated from the carrier  43 B. 
     Since the receptacle contacts  41  of the contact array S 4  and the receptacle contacts  41  of the contact array S 3  are joined to the carrier  43 B situated on the −X direction side of the receptacle housing  31  via the corresponding joint portions  42 , once the joint portions  42  are cut, consequently, the mounting portions  41 A of the receptacle contacts  41  of the contact array S 4  all extend in the −X direction so as to protrude from the −X directional end of the receptacle housing  31 , and the mounting portions  41 A of the receptacle contacts  41  of the contact array S 3  all extend in the −X direction so as to protrude in the opening portion  36 B of the receptacle housing  31 . 
     Thus, all of the receptacle contacts  41  of the contact arrays S 1  to S 4  can be separated together from the carriers  43 A and  43 B by means of the four carrier separating tools  44  in one step. 
     The foregoing method makes it possible to manufacture the receptacle connector  11  having a large number of receptacle contacts  41  with fewer manufacturing steps. 
     The plug connector  21  is able to fit with the receptacle connector  11  serving as a counter connector, and as shown in  FIGS. 13 to 15 , has a center line C 2  extending in the Y direction. In the plug connector  21 , the contact arrays T 1  and T 2  are disposed on the +X direction side of the center line C 2 , and the contact arrays T 3  and T 4  are disposed on the −X direction side of the center line C 2 . 
     The plug housing  51  of the plug connector  21  is made of an insulating body such as insulating resin, has a substantially flat plate shape, and includes a flat surface portion  52  extending along an XY plane on the +Z side of the plug housing  51 . A peripheral wall portion  53  protruding in the −Z direction is formed along the outer periphery of the flat surface portion  52 , and two partition portions  54 A and  54 B are formed in the area surrounded by the peripheral wall portion  53  and project in the −Z direction from the flat surface portion  52  while extending in the Y direction in parallel to each other. 
     The plug housing  51  has four contact array retaining portions  55  disposed separately on the −X direction side of the +X directional part of the peripheral wall portion  53 , on the −X direction side of the partition portion  54 A situated on the +X direction side, on the +X direction side of the partition portion  54 B situated on the −X direction side, and on the +X direction side of the −X directional part of the peripheral wall portion  53 . The four contact array retaining portions  55  extend in the Y direction and separately retain the contact arrays T 1  to T 4 . 
     In the plug housing  51 , an opening portion  56 A extending in the Y direction and penetrating the plug housing  51  in the Z direction is formed on the +X direction side of the partition portion  54 A situated on the +X direction side, and an opening portion  56 B extending in the Y direction and penetrating the plug housing  51  in the Z direction is formed on the −X direction side of the partition portion  54 B situated on the −X direction side. 
     Two positioning projection portions  57  are formed on the peripheral wall portion  53  at the +Y directional end of the plug housing  51  at a certain interval in the X direction to project in the +Y direction, while one positioning projection portion  57  is formed on the peripheral wall portion  53  at the −Y directional end of the plug housing  51  to project in the +Y direction. 
     As shown in  FIG. 16 , each contact array retaining portion  55  has a plurality of contact accommodating grooves  58  aligned in the Y direction. Although not illustrated, each contact accommodating groove  58  is provided in its inside with a retaining portion for retaining the corresponding plug contact  61 . 
     As shown in  FIG. 17 , the plug contact  61  is formed by bending a band-shaped metal plate having electrical conductivity, and has a mounting portion  61 A at its one end and a contact portion  61 B at its other end. The mounting portion  61 A extends along an XY plane and, when the plug connector  21  is mounted onto a mounting object such as a circuit board, is joined and fixed to a connecting pad or the like of the mounting object. Meanwhile, the contact portion  61 B is a fixed contact that is not elastically displaceable and, when the plug connector  21  is connected to the receptacle connector  11  serving as the counter connector, comes into contact with the corresponding receptacle contact  41  of the receptacle connector  11 . 
     The plug contact  61  further has a portion to be retained  61 C between the mounting portion  61 A and the contact portion  61 B. The portion to be retained  61 C has a pair of jutting portions  61 D jutting separately in the +Y direction and the −Y direction from the band-shaped metal plate forming the plug contact  61 . By press-fitting the portion to be retained  61 C having the jutting portions  61 D into the retaining portion of the corresponding contact accommodating groove  58  of the plug housing  51  from the +Z direction side, the plug contact  61  is retained by the contact accommodating groove  58 . 
     The plug contact  61  has a larger width in the Y direction at the pair of jutting portions  61 D than that at the other portions, and the width in the Y direction of the plug contact  61  at the pair of jutting portions  61 D is defined as a contact width W 2 . 
     As shown in  FIG. 18 , the plug contacts  61  constituting each of the contact arrays T 1  to T 4  are aligned in the Y direction at the same array pitch P 1  as that of the receptacle contacts  41  of the receptacle connector  11 , and the adjacent contact arrays T 1  and T 2  are arranged to be offset from each other in the Y direction by the offset amount P 2  equal to a half of the array pitch P 1 . The array pitch P 1  is set to be larger than a double of the contact width W 2  of the plug contact  61 . In other words, the offset amount P 2  equal to a half of the array pitch P 1  is set to be larger than the contact width W 2  of the plug contact  61 . 
     Accordingly, the plug contacts  61  constituting the contact array T 1  and the plug contacts  61  constituting the contact array T 2  are arranged to be offset from each other in the Y direction by the offset amount P 2  and do not overlap each other at all in the X direction perpendicular to the Y direction. 
     The adjacent contact arrays T 3  and T 4  are also arranged to be offset from each other in the Y direction by the offset amount P 2 . The plug contacts  61  constituting the contact array T 3  and the plug contacts  61  constituting the contact array T 4  are arranged to be offset from each other in the Y direction by the offset amount P 2  and do not overlap each other at all in the X direction perpendicular to the Y direction. 
     The contact arrays T 1  and T 4  are disposed at the same position in the Y direction with no offset, and the contact arrays T 2  and T 3  are also disposed at the same position in the Y direction with no offset. 
     Therefore, when the plug connector  21  is cut along an XZ plane passing through given plug contacts  61  of the contact arrays T 1  and T 4 , as shown in  FIG. 19 , the plug contact  61  of the contact array T 1  and the plug contact  61  of the contact array T 4  appear in the cross section, whereas for the contact arrays T 2  and T 3 , no plug contact  61  appears in the cross section with only a section of the plug housing  51  being seen. 
     Similarly, when the plug connector  21  is cut along an XZ plane passing through given plug contacts  61  of the contact arrays T 2  and T 3 , as shown in  FIG. 20 , the plug contact  61  of the contact array T 2  and the plug contact  61  of the contact array T 3  appear in the cross section, whereas for the contact arrays T 1  and T 4 , no plug contact  61  appears in the cross section with only a section of the plug housing  51  being seen. 
     On the +X direction side in the plug connector  21 , all of the mounting portions  61 A of the plug contacts  61  of the adjacent contact arrays T 1  and T 2  extend in the +X direction, which is an elongation direction, along the flat surface portion  52  of the plug housing  51 . All of the mounting portions  61 A of the plug contacts  61  of the contact array T 1  protrude in the +X direction from the +X directional end of the plug housing  51 , and all of the mounting portions  61 A of the plug contacts  61  of the contact array T 2  protrude in the opening portion  56 A of the plug housing  51  that is situated on the +X direction side of the contact array T 2 . 
     Similarly, on the −X direction side in the plug connector  21 , all of the mounting portions  61 A of the plug contacts  61  of the adjacent contact arrays T 3  and T 4  extend in the −X direction, which is an elongation direction, along an XY plane. All of the mounting portions  61 A of the plug contacts  61  of the contact array T 3  protrude in the opening portion  56 B of the plug housing  51  that is situated on the −X direction side of the contact array T 3 , and all of the mounting portions  61 A of the plug contacts  61  of the contact array T 4  protrude in the −X direction from the −X directional end of the plug housing  51 . 
     A method of manufacturing the plug connector  21  as above is described. As shown in  FIG. 21 , the plug contacts  61  constituting the contact array T 1  and the plug contacts  61  constituting the contact array T 2  are joined to a single carrier  63 A via associated joint portions  62 , and the plug contacts  61  constituting the contact array T 4  and the plug contacts  61  constituting the contact array T 3  are joined to another single carrier  63 B via associated joint portions  62 . The joint portions  62  connect the mounting portions  61 A of the respective plug contacts  61  to the corresponding carrier  63 A or  63 B. 
     Note that, as shown in  FIG. 18 , the plug contacts  61  constituting the contact array T 1  and the plug contacts  61  constituting the contact array T 2  are arranged so as not to overlap each other in the X direction. This configuration allows the plug contacts  61  constituting the contact array T 1  and the plug contacts  61  constituting the contact array T 2  to be joined to the single carrier  63 A. 
     Similarly, the plug contacts  61  constituting the contact array T 4  and the plug contacts  61  constituting the contact array T 3  are arranged so as not to overlap each other in the X direction. This configuration allows the plug contacts  61  constituting the contact array T 4  and the plug contacts  61  constituting the contact array T 3  to be joined to the other single carrier  63 B. 
     When the two carriers  63 A and  63 B are moved toward the plug housing  51  from the +Z direction side to the −Z direction side, the plug contacts  61  of the contact arrays T 1  to T 4  are fitted and accommodated into the corresponding contact accommodating grooves  58  of the plug housing  51 . At this time, the portion to be retained  61 C having the pair of jutting portions  61 D shown in  FIG. 17  in each plug contact  61  is press-fitted into and retained by the retaining portion of the corresponding contact accommodating groove  58 . 
     Thus, as shown in  FIG. 22 , all of the plug contacts  61  of the contact arrays T 1  to T 4  can be press-fitted together into the plug housing  51  by means of the two carriers  63 A and  63 B in one step. 
     The joint portions  62  connecting the plug contacts  61  of the contact array T 1  to the carrier  63 A extend in the +X direction from the +X directional end of the plug housing  51 , and the joint portions  62  connecting the plug contacts  61  of the contact array T 2  to the carrier  63 A extend across the opening portion  56 A of the plug housing  51  that is situated on the +X direction side of the contact array T 2  and further extend in the +X direction from the +X directional end of the plug housing  51 . 
     In contrast, the joint portions  62  connecting the plug contacts  61  of the contact array T 4  to the carrier  63 B extend in the −X direction from the −X directional end of the plug housing  51 , and the joint portions  62  connecting the plug contacts  61  of the contact array T 3  to the carrier  63 B extend across the opening portion  56 B of the plug housing  51  that is situated on the −X direction side of the contact array T 3  and further extend in the −X direction from the −X directional end of the plug housing  51 . 
     Next, as shown in  FIG. 22 , the plug contacts  61  are separated from the two carriers  63 A and  63 B by means of four carrier separating tools  64 . Each of the four carrier separating tools  64  is a plate member extending along a YZ plane and is provided at its+Z directional end with a blade portion extending along the Y direction. The four carrier separating tools  44  are arranged at intervals in the X direction. 
     Of the four carrier separating tools  64 , the carrier separating tool  64  situated furthest on the +X direction side is disposed slightly away from the +X directional end of the plug housing  51  in the +X direction, and the carrier separating tool  64  situated furthest on the −X direction side is disposed slightly away from the −X directional end of the plug housing  51  in the −X direction. 
     Further, of the four carrier separating tools  64 , the carrier separating tool  64  that is the second from the end on the +X direction side is disposed at a position corresponding to the opening portion  56 A of the plug housing  51  that is situated on the +X direction side of the contact array T 2 , and the carrier separating tool  64  that is the second from the end on the −X direction side is disposed at a position corresponding to the opening portion  56 B of the plug housing  51  that is situated on the −X direction side of the contact array T 3 . 
     The four carrier separating tools  64  as above are moved from the −Z direction side toward the +Z direction side, and the blade portions at the +Z directional ends of the carrier separating tools  64  are each pressed to the joint portions  62  of the corresponding carrier  63 A or  63 B; as a result, the joint portions  62  are cut, and the plug contacts  61  are separated from the carrier  63 A or  63 B. 
     In this process, of the four carrier separating tools  64 , the carrier separating tool  64  situated furthest on the +X direction side is moved in the +Z direction along a course slightly away from the +X directional end of the plug housing  51  in the +X direction, whereby the plug contacts  61  of the contact array T 1  are separated from the carrier  63 A, and the carrier separating tool  64  that is the second from the end on the +X direction side is moved in the +Z direction through the opening portion  56 A of the plug housing  51 , whereby the plug contacts  61  of the contact array T 2  are separated from the carrier  63 A. 
     Since the plug contacts  61  of the contact array T 1  and the plug contacts  61  of the contact array T 2  are joined to the carrier  63 A situated on the +X direction side of the plug housing  51  via the corresponding joint portions  62 , once the joint portions  62  are cut, consequently, the mounting portions  61 A of the plug contacts  61  of the contact array T 1  all extend in the +X direction so as to protrude from the +X directional end of the plug housing  51 , and the mounting portions  61 A of the plug contacts  61  of the contact array T 2  all extend in the +X direction so as to protrude in the opening portion  56 A of the plug housing  51 . 
     Further, of the four carrier separating tools  64 , the carrier separating tool  64  situated furthest on the −X direction side is moved in the +Z direction along a course slightly away from the −X directional end of the plug housing  51  in the −X direction, whereby the plug contacts  61  of the contact array T 4  are separated from the carrier  63 B, and the carrier separating tool  64  that is the second from the end on the −X direction side is moved in the +Z direction through the opening portion  56 B of the plug housing  51  that is situated on the −X direction side of the contact array T 3 , whereby the plug contacts  61  of the contact array T 3  are separated from the carrier  63 B. 
     Since the plug contacts  61  of the contact array T 4  and the plug contacts  61  of the contact array T 3  are joined to the carrier  63 B situated on the −X direction side of the plug housing  51  via the corresponding joint portions  62 , once the joint portions  62  are cut, consequently, the mounting portions  61 A of the plug contacts  61  of the contact array T 4  all extend in the −X direction so as to protrude from the −X directional end of the plug housing  51 , and the mounting portions  61 A of the plug contacts  61  of the contact array T 3  all extend in the −X direction so as to protrude in the opening portion  56 B of the plug housing  51 . 
     Thus, all of the plug contacts  61  of the contact arrays T 1  to T 4  can be separated together from the carriers  63 A and  63 B by means of the four carrier separating tools  64  in one step. 
     The foregoing method makes it possible to manufacture the plug connector  21  having a large number of plug contacts  61  with fewer manufacturing steps. 
     The connector assembly in the fitting state is shown in  FIGS. 23 and 24 . With the plug connector  21  being aligned with the receptacle connector  11 , the plug connector  21  is pressed to the receptacle connector  11  in the −Z direction so that the plug connector  21  is fitted into the receptacle connector  11 , thus making the connector assembly. 
     In the fitting state, the peripheral wall portion  53  of the plug housing  51  of the plug connector  21  enters the area surrounded by the peripheral wall portion  33  of the receptacle housing  31  of the receptacle connector  11 , and the three positioning projection portions  57  of the plug connector  21  are inserted into the three positioning recess portions  37  of the receptacle connector  11 , correspondingly. 
     Consequently, as shown in  FIG. 25 , the plug contacts  61  constituting the contact arrays T 1  and T 4  of the plug connector  21  come into contact with the receptacle contacts  41  constituting the contact arrays S 1  and S 4  of the receptacle connector  11 , correspondingly. Specifically, the contact portion  61 B of each plug contact  61  shown in FIG.  17  comes into contact with the contact portion  41 B of the corresponding receptacle contact  41  shown in  FIG. 7  with predetermined contact pressure, whereby the plug contacts  61  and the receptacle contacts  41  are electrically connected to each other. 
     Similarly, as shown in  FIG. 26 , the plug contacts  61  constituting the contact arrays T 2  and T 3  of the plug connector  21  come into contact with the receptacle contacts  41  constituting the contact arrays S 2  and S 3  of the receptacle connector  11 , correspondingly, whereby the plug contacts  61  and the receptacle contacts  41  are electrically connected to each other. 
     Since the three positioning projection portions  57  of the plug connector  21  are inserted into the three positioning recess portions  37  of the receptacle connector  11 , correspondingly, the plug connector  21  can be prevented from being fitted with the receptacle connector  11  in a wrong orientation. 
     In the receptacle connector  11 , while the receptacle contacts  41  constituting the contact array S 1  and the receptacle contacts  41  constituting the contact array S 2  are arranged so as not to overlap each other at all in the X direction, it suffices if the former contacts  41  and the latter contacts  41  are in a position other than a position where the former contacts  41  and the latter contacts  41  completely coincide with each other in the X direction. The former contacts  41  and the latter contacts  41  can be joined to the single carrier  43 A even when they partially overlap each other in the X direction. 
     For instance, when the mounting portions  41 A of the receptacle contacts  41  constituting the contact array S 1  and the mounting portions  41 A of the receptacle contacts  41  constituting the contact array S 2  are arranged to overlap each other in the X direction, and the contact portions  41 B of the receptacle contacts  41  constituting the contact array S 1  and the contact portions  41 B of the receptacle contacts  41  constituting the contact array S 2  are arranged so as not to overlap each other in the X direction, it is possible to connect the receptacle contacts  41  constituting the contact array S 1  and the receptacle contacts  41  constituting the contact array S 2  to the single carrier  43 A. 
     Similarly, in the receptacle connector  11 , while the receptacle contacts  41  constituting the contact array S 4  and the receptacle contacts  41  constituting the contact array S 3  are arranged so as not to overlap each other at all in the X direction, it suffices if the former contacts  41  and the latter contacts  41  are in a position other than a position where the former contacts  41  and the latter contacts  41  completely coincide with each other in the X direction. The former contacts  41  and the latter contacts  41  can be joined to the single carrier  43 B even when they partially overlap each other in the X direction. 
     In the plug connector  21 , it suffices if the plug contacts  61  constituting the contact array T 1  and the plug contacts  61  constituting the contact array T 2  do not completely coincide with each other in the X direction, and the former contacts  61  and the latter contacts  61  can be joined to the single carrier  63 A even when they partially overlap each other. 
     Similarly, it suffices if the plug contacts  61  constituting the contact array T 4  and the plug contacts  61  constituting the contact array T 3  do not completely coincide with each other in the X direction, and the former contacts  61  and the latter contacts  61  can be joined to the single carrier  63 B even when they partially overlap each other. 
     The receptacle connector  11  has the four contact arrays S 1  to S 4 , and the plug connector  21  has the four contact arrays T 1  to T 4 ; however, the invention is not limited thereto, and it suffices if the receptacle connector  11  and the plug connector  21  each have two or more contact arrays. 
     For instance, when the receptacle connector  11  has only two contact arrays S 1  and S 2 , the receptacle contacts  41  constituting the two contact arrays S 1  and S 2  are all joined to the single carrier  43 A, so that all of the receptacle contacts  41  can be press-fitted together into the receptacle housing  31  in one step and separated together from the carrier  43 A in another one step. 
     Similarly, when the plug connector  21  has only two contact arrays T 1  and T 2 , the plug contacts  61  constituting the two contact arrays T 1  and T 2  are all joined to the single carrier  63 A, so that all of the plug contacts  61  can be press-fitted together into the plug housing  51  in one step and separated together from the carrier  63 A in another one step. 
     The number of contact arrays joined to one carrier is not limited to two, and three or more contact arrays may be joined to one carrier. 
     It suffices if each contact array is formed by aligning the plural receptacle contacts  41  or the plural plug contacts  61 , and the number of the receptacle contacts  41  or the plug contacts  61  aligned in one contact array is not limited.