Patent Publication Number: US-7722365-B2

Title: Connector and electronic control apparatus having the same

Description:
CROSS REFERENCE TO RELATED APPLICATION 
   This application is based on and incorporates herein by reference Japanese Patent Application No. 2008-759 filed on Jan. 7, 2008. 
   FIELD OF THE INVENTION 
   The present invention relates to a connector adapted to be mounted on a wiring board and also relates to an electronic control apparatus having the connector and the wiring board. 
   BACKGROUND OF THE INVENTION 
   As disclosed in, for example, JP-A-2000-164273, a through-hole connector is mounted on a wiring board such that terminals of the through-hole connector are inserted into through holes in the wiring board and soldered to lands in the through holes. As disclosed in, for example, JP-A-2007-179974, a surface-mount connector is mounted on a wiring board such that terminals of the through-hole connector are soldered to lands on a surface of the wiring board. 
   In the through-hole connector disclosed in JP-A-2000-164273, the terminals are supported by a tine plate at a position near a surface of the wiring board to accurately position the terminals with respect to the lands. However, the terminals may not be accurately positioned with respect to the lands, due to manufacturing variations in the tine plate. Further, since the tine plate is fixed to a connector housing, the terminals may not be accurately positioned with respect to the lands, due to variations in assembly of the tine plate to the connector housing. 
   In such a through-hole connector with a tine plate, when the length of the terminal between a first portion supported by the tine plate and a second portion soldered to the land of the wiring board is short, the terminal is subjected to a lot of stress. Since the stress can cause disconnection between the terminal and the land, there is a need to increase the length of the terminal between the first and second portions. That is, the length of the terminal between the tine plate and the wiring board needs to be increased to reduce the stress applied to the terminal. As a result, the distance between the tine plate and the wiring board is increased. Accordingly, the size of the connector in a direction perpendicular to the surface of the wiring board is increased. 
   In the surface-mount connector disclosed in JP-A-2007-179974, the terminals are soldered to the lands on the wiring board by a reflow soldering process. Since a tine plate for supporting the terminals cannot be used in the reflow soldering process, it is difficult to accurately position the terminals with respect to the lands. Further, since the terminals are arranged in a line in the length direction of a connector housing, the distance between adjacent terminals decreases in an increase in the number of the terminals. As a result, crosstalk problems may be likely to occur, when the connector has a large number of terminals. 
   SUMMARY OF THE INVENTION 
   In view of the above, it is an object of the present invention to provide a connector configured such that even when the connector has a large number of terminals, the terminals can be accurately positioned with respect to lands of a wiring board, and a crosstalk between adjacent terminals can be reduced. It is another object of the present invention to provide an electronic control apparatus having the connector. 
   According to an aspect of the present invention, a connector includes a housing and multiple terminals arranged in the housing in a length direction of the housing. The housing of the connector has an electrically insulating property and is adapted to be mounted on a surface of a wiring board having multiple lands. The housing has first and second sides opposite to each other in a width direction of the housing. Each terminal of the connector is exposed to the first side of the housing at one end to be electrically connected to the wiring board and exposed to the second side of the housing at the other end to be electrically connected to an external connector. Each terminal includes a first parallel portion, a joint portion, a second parallel portion, and a contact portion. The first parallel portion is partially supported by the housing and extends substantially parallel to the surface of the wiring board. The second parallel portion is exposed outside the housing and extends substantially parallel to the surface of the wiring board. The second parallel portion is located closer to the surface of the wiring board than the first parallel portion in a direction perpendicular to the surface of the wiring board. The joint portion extends substantially perpendicular to the surface of the wiring board. The joint portion has a first end joined to the first parallel portion and a second end exposed outside the housing and joined to a first end of the second parallel portion. A contact portion has a first end joined to a second end of the second parallel portion and a second end soldered to a corresponding land of the wiring board. The first parallel portions of the terminals are located at X different heights from the surface of the wiring board in a direction perpendicular to the surface of the wiring board, where X is an integer of two or more. The joint portions of the terminals are located at Y different distances from the second side of the housing in the width direction of the housing, where Y is an integer of two or more. A first one of the terminals has the first parallel portion located at a first height from the surface of the wiring board and has the joint portion located at a first distance from the second side of the housing. A second one of the terminals has the first parallel portion located at a second height, less than the first height, from the surface of the wiring board and has the joint portion located at a second distance, different than the first distance, from the second side of the housing. The joint portion of the first one of the terminals is supported by the housing at a position between the first parallel portion of the first one of the terminals and the first parallel portion of the second one of the terminals. 
   According to another aspect of the present invention, an electronic control apparatus includes the connector and a wiring board having multiple lands. The housing of the connector is placed on the surface of the wiring board. The contact portion of each terminal is soldered to a corresponding land. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above and other objectives, features and advantages of the present invention will become more apparent from the following detailed description made with check to the accompanying drawings. In the drawings: 
       FIG. 1  is a diagram illustrating an exploded view of an electronic control apparatus according to an embodiment of the present invention; 
       FIG. 2  is a diagram illustrating a top view of a connector mounted on a wiring board of the electronic control apparatus; 
       FIG. 3  is a diagram illustrating a first side view of the connector mounted on the wiring board of the electronic apparatus; 
       FIG. 4  is a diagram illustrating a second side view of the connector mounted on the wiring board of the electronic apparatus; 
       FIG. 5  is a diagram illustrating an enlarged view of a portion enclosed by a line V of  FIG. 2 ; 
       FIG. 6  is a diagram illustrating a cross-sectional view taken along line VI-VI of  FIG. 4 ; 
       FIG. 7  is a diagram illustrating an enlarged view of a portion enclosed by a line VII of  FIG. 3 ; 
       FIG. 8  is a diagram illustrating a cross-sectional view taken along line VIII-VIII of  FIG. 7 ; 
       FIG. 9  is a diagram illustrating a cross-sectional view taken along line IX-IX of  FIG. 7 ; 
       FIG. 10  is a diagram illustrating a cross-sectional view of an electronic control apparatus according to a modification of the embodiment; and 
       FIG. 11  is a diagram illustrating a cross-sectional view of an electronic control apparatus according to another modification of the embodiment. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   An electronic control apparatus  1  according to an embodiment of the present invention is described below with reference to  FIGS. 1-9 . For example, the electronic control apparatus  1  can be applied to an engine electronic control unit (ECU) of a vehicle. In the embodiment, the electronic control apparatus  1  has a non-waterproof structure. 
   As shown in  FIG. 1 , the electronic control apparatus  1  mainly includes a circuit board  30  and a connector  50 . The circuit board  30  includes a wiring board  31  and electronic devices  32  mounted on the wiring board  31 . The connector  50  includes a connector housing  60  and connector terminals  70  supported by the housing  60 . In the embodiment, the electronic control apparatus  1  further includes a casing  10  for accommodating the circuit board  30  and the connector  50 . 
   The casing  10  can be, for example, made of a resin material or a metal material such as iron. The casing  10  can be constructed of one piece or separate pieces assembled together. In the embodiment, as shown in  FIG. 1 , the casing  10  includes a case  11  shaped like a box with an opening and a substantially rectangular lid  12  that covers the opening of the case  11 . The case  11  has a connector opening (not shown) shaped to match the housing  60 . In a condition where the lid  12  is attached to the case  11 , for example, by a screw, while the circuit board  30  is entirely accommodated in the casing  10 , the connector  50  is partially exposed outside the casing  10  through the connector opening. 
   As mentioned above, the circuit board  30  includes the wiring board  31  and the electronic devices  32  mounted on the wiring board  31 . The wiring board  31  has wiring patterns (not shown) joined to the electronic devices  32  and via holes (not shown) connecting the wiring patters. Examples of the electronic devices  32  include microcomputers (i.e., microprocessors), power transistors, resistors, and capacitors. The connector  50  is also mounted on the wiring board  31  and configured to electrically connect the circuit board  30  to an external device. 
   As mentioned above, the connector  50  includes the housing  60  and the terminals  70  supported by the housing  60 . The housing  60  is made of an electrically insulating material such as resin. The housing  60  has a substantially rectangular prism shape with length and width directions as indicated in  FIG. 2 . The connector terminals  70  are made of an electrically conductive material such as copper. As shown in  FIG. 6 , each connector terminal  70  is exposed at one end to a first side  60   a  of the housing  60  and electrically coupled to the circuit board  30 , which is accommodated in the casing  10 . Each connector terminal  70  is exposed at the other end to a second side  60   b  of the housing  60  and located outside the casing  10  to be electrically connected to an external connector (not shown). 
   The connector terminal  70  can be a stamped terminal that is formed by stamping a sheet metal into a predetermined shape. Alternatively, the connector terminal  70  can be a bent terminal that is formed by stamping a metal sheet into a straight shape, inserting the straight-shaped terminal into the housing  60 , and then bending the straight-shaped terminal into the predetermined shape. The connector terminal  70  can have an accurate shape, when the connector terminal  70  is a stamped terminal as compared to when the connector terminal  70  is a bent terminal. The connector terminal  70  can be brass plated. 
   As shown in  FIGS. 2-4 , the connector terminals  70  are supported by the housing  60  and arranged in the length direction of the housing  60  so as not to interfere with each other. In the embodiment, the connector terminals  70  include power terminals  71 ,  72  and signal terminals  73 - 76 . The power terminals  71 ,  72  are used for electric power transmission, and the signal terminals  73 - 76  are used for signal transmission. The power terminals  71 ,  72  are identical in diameter, and the signal terminals  73 - 76  are identical in diameter. In other words, the power terminals  71 ,  72  are identical in cross section, and the signal terminals  73 - 76  are identical in cross section. A diameter of each of the power terminals  71 ,  72  is greater than a diameter of each of the signal terminals  73 - 76 . 
   As shown in  FIGS. 5 ,  6 , the wiring board  31  has through holes  33  and conductive lands  34 - 39 . The lands  34 - 39  are integrally formed on inner walls of the through holes  33  and around openings of the through holes  33 , respectively. The through holes  33  penetrate through the wiring board  31  in a direction perpendicular to a surface  31  a of the wiring board  31 . 
   The lands  34 - 39  correspond to the terminals  71 - 76 , respectively. That is, the terminals  71 - 76  are inserted into the through holes  33  and electrically joined to the lands  34 - 39  through solders  90 , respectively. The shape and size of the through holes  33  are adjusted to match the terminals  71 - 76 . For example, since the power terminals  71 ,  72  have the diameter greater than the diameter of the signal terminals  73 - 76 , the through holes  33  for receiving the power terminals  71 ,  72  have the diameter greater than the diameter of the through holes  33  for receiving the signal terminals  73 - 76 . 
   The lands  34  for the power terminals  71  are arranged in a line in the length direction of the housing  60 . The lands  35  for the power terminals  72  are arranged in a line in the length direction of the housing  60 . The land  35  is located farther from the second side  60   b  of the housing  60  than the land  34  in the width direction of the housing  60 . The lands  34 ,  35  are alternately arranged in the length direction of the housing  60  to form a two-legged zigzag arrangement. 
   The lands  36  for the signal terminals  73  are arranged in a line in the length direction of the housing  60 . The lands  37  for the signal terminals  74  are arranged in a line in the length direction of the housing  60 . The lands  38  for the signal terminals  75  are arranged in a line in the length direction of the housing  60 . The lands  39  for the signal terminals  76  are arranged in a line in the length direction of the housing  60 . The land  37  is located farther from the second side  60   b  of the housing  60  than the land  36  in the width direction of the housing  60 . The land  38  is located farther from the second side  60   b  than the land  37 . The land  39  is located farther from the second side  60   b  than the land  38 . The lands  37 ,  39 ,  36 ,  38  are alternately arranged in this order in the length direction of the housing  60  so as to provide a four-legged zigzag arrangement. 
   Each connector terminal  70  has a first parallel portion  70   a,  a first joint portion  70   b,  a second parallel portion  70   c,  and a contact portion  70   d.  For example, as shown in  FIG. 6 , the signal terminals  73 - 76  have first parallel portions  73   a - 76   a,  first joint portions  73   b - 76   b,  second parallel portions  73   c - 76   c,  and contact portions  73   d - 76   d,  respectively. Although not shown in the drawings, the power terminals  71 ,  72  have first parallel portions  71   a,    72   a,  first joint portions  71   b,    72   b,  second parallel portions  71   c,    72   c,  and contact portions  71   d,    72   d.    
   The first parallel portion  70   a  of the connector terminal  70  extends substantially parallel to the surface  31   a  of the wiring board  31  in the width direction of the housing  60 . The first parallel portion  70   a  has a first end that projects from the second side  60   b  of the housing  60  to be electrically connected to the external connector. A second end of the first parallel portion  70   a  is supported by the housing  60 . 
   Specifically, as exemplified in  FIG. 6  by the first parallel portions  74   a,    76   a  of the signal terminals  74 ,  76 , the second end of the first parallel portion  70   a  is placed in a through hole  61  and a slit  62  formed in the housing  60 . The through hole  61  penetrates through the housing  60  in the width direction of the housing  60 . The slit  62  is formed on the first side  60   a  and extends in the direction perpendicular to the surface  31   a  of the wiring board  31 . The upper end of the slit  62  communicates with the through hole  61 . In the embodiment, the first parallel portion  70   a  is inserted in the through hole  61  and the slit  62  from the first side  60   a  of the housing  60 . 
   A projection  77  is formed on an outer surface of the second end of the first parallel portion  70   a,  and a recess  61   a  is formed on an inner wall of the through hole  61 . When the first parallel portion  70   a  is inserted in the through hole  61 , the projection  77  of the first parallel portion  70   a  is received in (i.e., engaged with) the recess  61   a  of the through hole  61  to prevent the first parallel portion  70   a  from moving toward the first side  60   a  of the housing  60 . Further, the joint portion  70   b  and a bottom  62   b  (refer to  FIG. 8 ) of the slit  62  prevents the first parallel portion  70   a  from moving toward the second side  60   b  of the housing  60 . Thus, the terminal  70  remains supported by the housing  60 . 
   As shown in, for example,  FIGS. 3 ,  4 , the first parallel portions  71   a,    72   a  of the power terminals  71 ,  72  are located at two different heights from the surface  31   a  of the wiring board  31  in the direction perpendicular to the surface  31   a.  Further, the first parallel portions  71   a,    72   a  are alternately arranged in the length direction of the housing  60  to form a two-legged zigzag arrangement. Specifically, the first parallel portion  71   a  is located at a first height from the surface  31   a,  and the first parallel portion  72   a  is located at a second height greater than the first height. 
   As shown in, for example,  FIG. 6 , the first parallel portions  73   a - 76   a  of the signal terminals  73 - 76  are located at four different heights from the surface  31   a  of the wiring board  31  in the direction perpendicular to the surface  31   a.  Specifically, the first parallel portion  73   a  is located at a third height from the surface  31   a,  the first parallel portion  74   a  is located at a fourth height greater than the third height, the first parallel portion  75   a  is located at a fifth height greater than fourth height, and the first parallel portion  76   a  is located at a sixth height greater than the fifth height. Further, the first parallel portions  76   a,    74   a,    75   a,  and  73   a  are alternately arranged in this order in the length direction of the housing  60  to form a four-legged zigzag arrangement. 
   As exemplified in  FIG. 6  by the second parallel portions  74   c,    76   c  of the signal terminals  74 ,  76 , the second parallel portion  70   c  is located closer to the surface  31  a of the wiring board  31  than the first parallel portion  70   a  and extends substantially parallel to the surface  31   a  in the width direction of the housing  60 . The second parallel portion  70   c  is entirely exposed outside the housing  60  on the first side  60   a  side. The second parallel portion  70   c  has a first end joined to the second end of the joint portion  70   b  and a second end joined to a first end of the contact portion  70   d.  That is, the first and second parallel portions  70   a,    70   c  are joined together by the joint potion  70   b.    
   As exemplified in  FIG. 6  by the joint portions  74   b,    76   b  of the signal terminals  74 ,  76 , the joint portion  70   b  extends substantially perpendicular to the surface  31  a of the wiring board  31 . The joint portion  70   b  has a first end joined to the second end of the first parallel portion  70   a  and a second end projecting from the first side  60   a  of the housing  60  toward the surface  31   a  of the wiring board  31 . The joint portion  70   b  is partially supported by the housing  60  in such a manner that the second end of the joint portion  70   b  is exposed outside the housing  60 . In the embodiment, as shown in, for example,  FIGS. 6-9 , the first end of the joint portion  70   b  is placed in the slit  62  and thus supported by the housing  60 . As clearly illustrated in  FIG. 8 , the joint portion  70   b  placed in the slit  62  does not touch a plane formed by the first side  60   a.  In such an approach, a foreign matter sticking to the first side  60   a  cannot touch the joint portion  70   b.  Therefore, even when the foreign matter has an electrical conductivity, the foreign matter does not cause a short-circuit between adjacent joint portions  70   b.    
   The joint portions  71   b,    72   b  of the power terminals  71 ,  72  are located at different distances from the second side  60   b  of the housing  60  in the width direction of the housing  60 . Specifically, the joint portion  72   b  is located at a first distance from the second side  60   b,  and the joint portion  71   b  is located at a second distance greater than the first distance. 
   The joint portions  73   b,    74   b  of the signal terminals  73 ,  74  are located at the same distance from the second side  60   b  of the housing  60  in the width direction of the housing  60 . The joint portions  75   b,    76   b  of the signal terminals  75 ,  76  are located at the same distance from the second side  60   b  of the housing  60  in the width direction of the housing  60 . Specifically, each of the joint portions  73   b,    74   b  is located at a third distance from the second side  60   b,  and each of the joint portions  75   b,    76   b  is located at a fourth distance greater than the fourth distance. Thus, the joint portions  73   b - 76   b  of the signal terminals  73 - 76  are located at two different distances from the second side  60   b  of the housing  60  in the width direction of the housing  60 . 
   In the embodiment, the terminals  70  having the same diameter are classified into first and second terminals  78 ,  79  according to the distance of the joint portion  70   b  from the second side  60   b  of the housing  60 . For example, the power terminal  72  and the signal terminals  75 ,  76  are classified as the first terminal  78 , and the power terminal  71  and the signal terminals  73 ,  74  are classified as the second terminal  79 . The joint portion  70   b  of the first terminal  78  is supported by the housing  60  at a position between the first parallel portions  70   a  of the first and second terminals  78 ,  79 . 
   Specifically, the joint portion  72   b  of the power terminal  72  as the first terminal  78  is supported by the housing  60  at a position between the first parallel portion  72   a  of the power terminal  72  and the first parallel portion  71   a  of the power terminal  71  as the second terminal  79 . The joint portion  75   b  of the signal terminal  75  as the first terminal  78  is supported by the housing  60  at a position between the first parallel portion  75   a  of the signal terminal  75  and the first parallel portion  73   a  of the signal terminal  73  as the second terminal  79 . The joint portion  76   b  of the signal terminal  76  as the first terminal  78  is supported by the housing  60  at a position between the first parallel portion  76   a  of the signal terminal  76  and the first parallel portion  74   a  of the signal terminal  74  as the second terminal  79 . 
   As shown, for example, in  FIG. 6 , in the first and second terminals  78 ,  79  having the same diameter, the second parallel portion  70   c  of the second terminal  79 , the second parallel portion  70   c  of the first terminal  78 , the first parallel portion  70   a  of the second terminal  79 , and the first parallel portion  70   a  of the first terminal  78  are arranged in this order from the surface  31   a  side. 
   As shown, for example, in  FIG. 9 , the joint portion  70   b  of the first terminal  78  (i.e., the joint portions  75   b,    76   b  of the signal terminals  75 ,  76 ) and the joint portion  70   b  of the second terminal  79  (i.e., the joint portions  73   b,    74   b  of the signal terminals  73 ,  74 ) are alternately arranged in the length direction of the housing  60  to form a two-legged zigzag arrangement. 
   The contact portion  70   d  of the terminal  70  is electrically joined to a corresponding one of the lands  34 - 39  of the wiring board  31 . In the embodiment, the wiring board  31  has through holes  33 . The lands  34 - 39  are integrally formed on inner walls of the through holes  33  and formed around openings of the through holes  33 . As shown in  FIGS. 5 and 6 , the contact portions  70   d  are inserted into through holes  33  and electrically joined to the lands  34 - 39  through solders  90 . 
   As shown in  FIG. 5 , the contact portions  71   d  of the power terminals  71  are arranged in a line in the length direction of the housing  60 . Likewise, the contact portions  72   d  of the power terminals  72  are arranged in a line in the length direction of the housing  60 . The contact portion  71   d  of the power terminal  71  as the first terminal  78  is located closer to the second side  61   b  of the housing  60  than the contact portion  72   d  of the power terminal  72  as the first terminal  78 . The contact portions  71  d,  72   d  are soldered to the lands  34 ,  35 , respectively, and alternately arranged in the length direction of the housing  60  to form a two-legged zigzag arrangement. 
   As shown in  FIG. 5 , the contact portions  73 d of the signal terminals  73  are arranged in a line in the length direction of the housing  60 . Likewise, the contact portions  74   d  of the signal terminals  74  are arranged in a line in the length direction of the housing  60 . Likewise, the contact portions  75   d  of the signal terminals  75  are arranged in a line in the length direction of the housing  60 . Likewise, the contact portions  76   d  of the signal terminals  76  are arranged in a line in the length direction of the housing  60 . The contact portion  74   d  of the signal terminal  74  as the second terminal  79  is located closer to the second side  61   b  of the housing  60  than the contact portion  73   d  of the signal terminal  73  as the second terminal  79 . The contact portion  74   d  of the signal terminal  74  as the second terminal  79  is located closer to the second side  61   b  of the housing  60  than the contact portion  76   d  of the signal terminal  76  as the first terminal  78 . The contact portion  76   d  of the signal terminal  76  as the first terminal  78  is located closer to the second side  61   b  of the housing  60  than the contact portion  75   d  of the signal terminal  75  as the first terminal  78 . The contact portions  73   d - 76   d  are soldered to the lands  36 - 39 , respectively. Further, the contact portions  73   d,    75   d,    74   d,  and  76   d  arranged in this order in the length direction of the housing  60  to form a four-legged zigzag arrangement. 
   Further, as shown in  FIG. 6 , the contact portion  70   d  has a cross-section (i.e., diameter) smaller than that of any other portion of the terminal  70  exposed outside housing  60  on the first side  60   a  side. Specifically, the contact portion  70   d  has a cross-section smaller than that of each of the second end of the joint portion  70   b  and the second parallel portion  70 c. In such an approach, the size of the through hole  33  is reduced so that the area of the wiring board  31  occupied by the though hole  33  can be reduced. Since each of the joint portion  70   b  and the second parallel portion  70   c  has a large cross section enough to reduce impedance of the terminal  70 , heat generated in the terminal  70  is reduced. Further, the large cross section of the joint portion  70   b  and the second parallel portion  70   c  increases strength of the terminal  70  so that a bend of the terminal  70  can be reduced. Therefore, the contact portions  70   d  can be inserted in the through holes  33  while positioning the terminals  70  with respect to the through holes  33 . 
   As shown in  FIGS. 2-4 , the connector  50  has one first terminal block  51  and two second terminal block  52  that are arranged in a line in the length direction of the housing  60 . The first terminal block  51  is constructed with only the signal terminals  73 - 76 . Each second terminal block  52  is constricted with both the power terminals  71 ,  72  and the signal terminals  73 - 76 . In the embodiment, the first and second terminal blocks  51 - 52  are respectively mated with three external connectors of an electrical system of an engine of the vehicle. As shown in  FIG. 4 , the first and second terminal blocks  51 - 52  are separated from each other by the second side  60   b  of the housing  60 . In such an approach, the housing  60  can be prevented from warping in the length direction. The arrangement of the terminal blocks and the arrangement of the terminals in the terminal block can vary according to the intended use, for example, as disclosed in Japanese Patent Application No. 20007-000888, which is filed by the present inventor. 
   In the embodiment, as shown in  FIGS. 2 ,  3 , the housing  60  is fixed to the wiring board  31  by four reinforcement pins  53  that are arranged in a line in the length direction of the housing  60  at a given interval. In such an approach, the connector  50  can be reliably fixed to the wiring board  31 . The number and arrangement of the reinforcement pins  53  can vary according to the intended use. Alternatively, the reinforcement pins  53  can be unnecessary, because the connector  50  can be securely fixed to the wiring board  31  by the contact portions  70 d, which are inserted in the through holes  33  and soldered to the lands  34 - 39  of the wiring board  31 . 
   In summary, the following advantages can be achieved according to the embodiment. The first end of the joint portion  70   b  is joined to the first parallel portion  70   a,  and the second end of the joint portion  70   b  is joined to the second parallel portion  70 c. As shown in  FIG. 6 , the first end of the joint portion  70   b  is supported by the housing  60 , and the second end of the joint portion  70   b  is exposed outside the housing  60 . That is, the second parallel portion  70   c  and the second end of the joint portion  70   b  are located between the contact portion  70   d  and the first end of the joint portion  70   b.  In such an approach, the length of the terminal  70  between the first side  60   a  of the housing  60  and the surface  31  a of the wiring board  31  becomes long enough to reduce stress applied to the terminal  70 . Thus, connection reliability between the terminals  70  and the lands  34 - 39  can be ensured without increasing the size of the connector  50  in the direction perpendicular to the surface  31  a of the wiring board  31 . 
   In particular, in the embodiment, the joint portion  70   b  of the first terminal  78  is supported by the housing  60  at a position between the first parallel portion  70   a  of the first terminal  78  and the first parallel portion  70   a  of the second terminal  79 . That is, the joint portion  70   b  of the first terminal  78  is supported by the housing  60  at a position relatively far away from the surface  31  a of the wiring board  31  in the direction perpendicular to the surface  31   a.  Therefore, the connection reliability can be effectively increased. 
   Further, in the embodiment, the first end of the joint portion  70   b  of the terminal  70  is covered with the housing  60 . For example, the length of the first end of the joint portion  70   b  can account for from about one-third to two-thirds of the total length of the joint portion  70   b.  In such an approach, the joint portion  70   b  is supported by the housing  60  at a position relatively far away from the surface  31  a of the wiring board  31  in the direction perpendicular to the surface  31   a.  Thus, the connection reliability between the terminals  70  and the lands  34 - 39  can be increased without increasing the size of the connector  50  in the direction perpendicular to the surface  31   a.  Since a top side (i.e., the first end) of the joint portion  70   b  is supported by the housing  60 , the housing  60  can be simplified in structure as compared to when a bottom side (i.e., the second end) of the joint portion  70   b  is supported by the housing  60 . Further, since the joint portion  70   b  is supported by a surface of the housing  60 , not a point of the housing  60 , the terminals  70  can be accurately positioned with respect to the lands  34 - 39 . 
   Specifically, as shown in  FIGS. 6 ,  7 , the housing  60  has a thick portion  63  and a thin portion  64 . The thickness of the thick portion  63  in the width direction of the housing  60  is greater than the thickness of the thin portion  64 . The first parallel portion  70   a  and the first end of the joint portion  70   b  of the first terminal  78  (i.e., the power terminal  72  and the signal terminals  75 ,  76 ) are supported by the thick portion  63 . The first parallel portion  70   a  and the first end of the joint portion  70   b  of the second terminal  79  (i.e., the power terminal  71  and the signal terminals  73 ,  74 ) are supported by the thin portion  64 . Due to the thickness difference between the thick portion  63  and the thin portion  64 , the housing  60  has a stepped shape at the first side  60   a.  The second end of the joint portion  70   b  of the first terminal  78  projects from a bottom  63   a  of the thick portion  63  and is located in front of the first side  60   a  of the thin portion  64  with a space therebetween. The second end of the joint portion  70   b  of the second terminal  79  projects from a bottom  64   a  of the thin portion  64  and is located in front of the first side  60   a  of a further thin portion  65  with a space therebetween. The thickness of the further thin portion  65  in the width direction of the housing  60  is smaller than the thickness of the thin portion  64 . In this way, the top side (i.e., the first end) of the joint portion  70   b  of each terminal  70  is supported by the housing  60 . 
   As shown in  FIGS. 6-9 , the first end of the joint portion  70   b  is placed in the slit  62  formed on the first side  60   a  of the housing  60 . For example, as shown in  FIG. 8 , opposing side walls  62   a  of the slit  62  prevent the joint portion  70   b  from being displaced in the length direction of the housing  60 . Accordingly, a rotational movement of the terminal  70  around the first parallel portion  70   a  is prevented. The rotational movement is indicated by a solid arrow in  FIG. 7 . Therefore, the terminals  70  (i.e., the contact portions  70   d ) can be accurately positioned with respect to the lands  34 - 39  without using a tine plate. 
   As shown, for example, in  FIG. 6 , the first parallel portions  70   a  are located at different heights from the surface  31   a  of the wiring board  31 . Further, the joint portions  70   b  are located at different distances from the second side  60   b  of the housing  60 . In this case, a distance between adjacent joint portions  70   b  is long compared to when the joint portions  70   b  are located at the same distance from the second side of the housing  60 . Accordingly, crosstalk between adjacent terminals  70  is less likely to occur. Therefore, the number of the terminals  70  can be increased without increasing the size of the housing  60  in the length direction. 
   As describe above, according to the embodiment, the connector  50  can have a large number of the terminals  70  without increasing the size. The terminals  70  can be accurately positioned with respect to the lands  34 - 39  and reliably connected to the lands  34 - 39 . The connector  50  is mounted on the circuit board  30  in such a manner that the contact portions  70   d  of the terminals  70  are located perpendicular to the surface  31   a  of the wiring board  31 , inserted in the through holes  33 , and soldered to the lands  34 - 39  that are formed on the inner walls of the through holes  33  and around the openings of the through holes  33 . That is, the connector  50  is configured as a through hole connector. Although the connector  50  is configured as a through hole connector, the terminals  70  can be accurately positioned with respect to the lands  34 - 39  without using a tine plate. Further, the terminals  70  can be reliably connected to the lands  34 - 39  without increasing the size of the connector  50  in the direction perpendicular to the surface  31  a of the wiring board  31 . 
   Further, according to the embodiment, as shown, for example, in  FIG. 6 , the second parallel portion  70   c  of the second terminal  79 , the second parallel portion  70   c  of the first terminal  78 , the first parallel portion  70   a  of the second terminal  79 , and the first parallel portion  70   a  of the first terminal  78  are arranged in this order from the surface  31  a side. That is, the second parallel portion  70   c  of the first terminal  78  is located closer to the surface  31  a than the first parallel portion  70   a  of the second terminal  79 . In such an approach, the length of a portion (e.g., contact portion  70   d ) of the first terminal  78  located closer to the surface  31   a  than the second parallel portion  70   c  can be reduced. Therefore, although the first parallel portion  70   a  of the first terminal  78  is located farther from the surface  31   a  of the wiring board  31  than the first parallel portion  70   a  of the second terminal  79 , the first terminal  78  can be accurately positioned with respect to the lands  35 ,  38 ,  39 . 
   In the embodiment, the signal terminals  73 - 76  are identical in cross-section (i.e., diameter). The joint portions  70   b  of the signal terminals  73 - 76  are located at X different distances from the second side  60   b  of the housing  60 , where X is two. Specifically, each of the joint portions  73   b,    74   b  is located at the third distance from the second side  60   b,  and each of the joint portions  75   b,    76   b  is located at the fourth distance greater than the fourth distance. On the other hands, the first parallel portions  70   a  of the signal terminals  73 - 76  are located at Y different heights from the surface  31   a  of the wiring board  31 , where Y is four. Specifically, the first parallel portion  73   a  is located at the third height from the surface  31   a,  the first parallel portion  74   a  is located at the fourth height greater than the third height, the first parallel portion  75   a  is located at the fifth height greater than fourth height, and the first parallel portion  76   a  is located at the sixth height greater than the fifth height. 
   In summary, the different distance step X (two) of the joint portions  70   b  is less than the different height step Y (four) of the first parallel portions  70   a  (i.e., 2≦X&lt;Y). In such an approach, although the terminal  70  has the second parallel portion  70   c  extending in the width direction of the housing  60 , the increase in the size of the connector  50  in the width direction can be prevented. In particular, in the embodiment, the different height step Y of the first parallel portions  70   a  is a multiple of the different distance step X of the joint portions  70   b.  Therefore, the connector  50  can have a large number of terminals  70  while preventing crosstalk between the adjacent terminals  70 . Further, the contact portions  70   d  of the signal terminals  73 - 76  are located at Z different distances from the second side  60   b  of the housing  60 , where Z is four. Specifically, the contact portion  74   d  is located closer to the second side  61   b  than the contact portion  73   d,  the contact portion  74   d  is located closer to the second side  61   b  than the contact portion  76   d,  and the contact portion  76   d  is located closer to the second side  61   b  than the contact portion  75   d.    
   In summary, the different distance step X (two) of the joint portions  70   b  is less than the different distance step Z (four) of the contact portions  70   d  (i.e., 2≦X&lt;Z). In such an approach, although the terminal  70  has the second parallel portion  70   c  extending in the width direction of the housing  60 , the increase in the size of the connector  50  in the width direction can be prevented. The distance between adjacent terminals  70  can be increased by increasing the different distance step Z. Accordingly, the crosstalk between adjacent terminals can be reduced. Further, the widths of the lands  36 - 39  can be increased by increasing the different distance step Z to improve the connection reliability between the terminals  73 - 76  and the lands  36 - 39 . The above-described requirements (e.g., 2≦X&lt;Y, 2≦X&lt;Z) can be applied to terminals  70  other than the signals terminals  73 - 76 , as long as the terminals  70  are identical in cross-section. For example, the above-described requirements can be applied to the power terminals  71 ,  72 . 
   According to the embodiment, the contact portions  70   d  of the terminals  70  having the same diameter are arrange in a zigzag manner. In such an approach, the crosstalk between adjacent terminals  70  can be reduced. Further, the widths of the lands  34 - 39  can be increased so that the connection reliability between the terminals  70  and the lands  34 - 39  can be improved. Furthermore, as compared to when the lands  34 - 39  are arranged in a line in the length direction of the housing  60 , the size of the wiring board  31  in the length direction can be reduced. 
   According to the embodiment, the terminals  70  are classified into the first and second terminals  78 ,  79  according to the distance of the joint portion  70   b  from the second side  60   b  of the housing  60 . The power terminal  72  and the signal terminals  75 ,  76  are classified as the first terminal  78 , and the power terminal  71  and the signal terminals  73 ,  74  are classified as the second terminal  79 . In each of the first and second terminals  78 ,  79  having the same diameter, the terminal  70  having the first parallel portion  70   a  located father from the surface  31   a  of the wiring board  31  has the contact portion  70   d  located closer to the second side  60   b  of the housing  60 . In other words, in each of the first and second terminals  78 ,  79  having the same diameter, the terminal  70  having the first parallel portion  70   a  located closer to the surface  31  a has the contact portion  70   d  located farther from the second side  60   b.  In such an approach, each first terminal  78  having the same diameter has substantially the same length, and the second terminals  79  having the same diameter has substantially the same length. For example, in the example shown in  FIG. 6 , the signal terminals  75 ,  76  as the first terminal  78  has substantially the same length. Accordingly, each first terminals  78  has substantially the same impedance, and each second terminal  79  has substantially the same impedance. Therefore, a local increase of temperature in the terminals  70  can be reduced. 
   According to the embodiment, in the terminals  70  having the same diameter, the joint portion  70   b  of the first terminal  78  and the joint portion  70   b  of the second terminal  79  are arranged in the length direction of the housing  60  to form a zigzag arrangement. In such an approach, a distance L (refer to  FIG. 9 ) between adjacent terminals  70  can be increased so that the crosstalk between the adjacent terminals  70  can be reduced. Further, as compared to a grid arrangement, the zigzag arrangement can allow a visual inspection for a solder joint between the contact portion  70   d  located closer to the housing  60  and the corresponding land to be easily performed. 
   (Modifications) 
   The embodiment described above can be modified in various ways. For example, although the terminals  70  have two types of power terminals  71 ,  72  and four types of signal terminals  73 - 76 , the number of types of the terminals  70  can vary according to the intended use of the connector  50 . For example, the terminals  70  can have one type of the terminals  70  having the same diameter or more than three types of the terminals  70  having the same diameter. The different distance step X of the joint portions  70   b,  the different height step Y of the first parallel portions  70   a,  and the different distance step Z of the contact portions  70   d  can vary according to the intended use, as long as each of the different distance step X and the different height step Y is two or more. 
   In the embodiment, the electronic control apparatus  1  is not made waterproof. Alternatively, the electronic control apparatus  1  can be made waterproof. 
   In the embodiment, as shown in  FIG. 9 , the joint portion  70   b  is placed in the slit  62  not to be exposed to the plane formed by the first side  60   a.  Alternatively, as shown in  FIG. 10 , the joint portion  70   b  can be placed in the slit  62  to be exposed to the plane formed by the first side  60   a.    
   In the embodiment, the first end of the joint portion  70   b  is joined to the second end of the first parallel portion  70   a  and supported by the housing  60 . In short, the joint portion  70   b  is supported by the housing  60  at a joint between the first parallel portion  70   a  and the joint portion  70   b.  Alternatively, the joint portion  70   b  can be supported by the housing  60  at a portion other than the joint between the first parallel portion  70   a  and the joint portion  70   b.  For example, as shown in  FIG. 11 , the joint portion  70   b  can be supported by the housing  60  at a portion located away from the joint between the first parallel portion  70   a  and the joint portion  70   b.  In such an approach, the joint between the first parallel portion  70   a  and the joint portion  70   b  are exposed outside the housing. Therefore, the terminals  70  can be easily inserted in the housing  60 . 
   In the embodiment, the contact portion  70   d  has an insertion portion that is inserted into the through hole  33  of the wiring board  31  and soldered to the corresponding land in the through hole  33  using a point soldering method. Alternatively, the contact portion  70   d  can have both the insertion portion and a surface-mount portion that is soldered to the corresponding land on the surface  31   a  using a reflow soldering method. Alternatively, the contact portions  70   d  can have only the surface-mount portion. 
   The contact portions  70   d  having the surface-mount structure can be mounted on the wiring board by a reflow soldering method. When the second parallel portion  70   c  of the first terminal  78  is located closer to the surface  31   a  of the wiring board  31  than the first parallel portion  70   a  of the second terminal  79 , reflow heat is effectively supplied to the contact portion  70   d  of the second terminal  79  without being blocked by the first terminal  78 , so that the connection reliability between the terminal  79  and the corresponding land can be increased. Therefore, as shown in  FIG. 6 , it is preferable that the second parallel portion  70   c  of the second terminal  79 , the second parallel portion  70   c  of the first terminal  78 , the first parallel portion  70   a  of the second terminal  79 , and the first parallel portion  70   a  of the first terminal  78  be arranged in this order from the surface  31   a  side. Further, in the terminals  70  having the same diameter, it is preferable that the first joint portion  70   b  of the first terminal  78  and the first joint portion  70   b  of the second terminal  79  are arranged in the length direction of the housing  60  to form a zigzag arrangement. In such an approach, the reflow heat is effectively supplied to the contact portion  70   d  of the second terminal  79  without being blocked by the joint portion  70   b  of the first terminal  78 , so that the connection reliability between the terminal  79  and the lands can be increased. Further, the zigzag arrangement can reduce the crosstalk between adjacent terminals  70  and can allow a visual inspection for the solder joint between the contact portion  70   d  of the second terminal  79  and the corresponding land to be easily performed. 
   In the example shown in  FIG. 11 , the contact portion  70   d  has both an insertion portion  70   e  and a surface-mount portion  70   f.  The surface-mount portion  70   f  extends substantially parallel to the surface  31   a  of the wiring board  31  in the width direction of the housing  60 . The insertion portion  70   e  extends perpendicular to the surface  31   a  of the wiring board  31  from a tip of the surface-mount portion  70   f  and inserted in the through hole  33  of the wiring board  31 . 
   For example, the terminal  70  can be a stamped terminal that is formed by stamping a sheet metal into a shape corresponding to the terminal  70 . Alternatively, the terminal  70  can be formed by stamping a sheet metal into a straight shape and then by bending the straight-shaped sheet metal into the corresponding shape. When the terminal  70  is the stamped terminal, design flexibility of the terminal  70  is improved so that the terminal  70  can have a complex shape. For example, the insertion portion  70   e  can extend perpendicular to the surface  31   a  of the wiring board  31  from a potion other than the tip of the surface-mount portion  70   f.  Specifically, as disclosed in, for example, Japanese Patent Application No. 2007-148613 filed by the present inventor, the insertion portion  70   e  can extend perpendicular to the surface  31   a  of the wiring board  31  from a middle potion of the surface-mount portion  70   f.    
   Further, in the example shown in  FIG. 11 , the terminal  70  includes six types of signal terminals. The first parallel portions  70   a  of the signal terminals are located at six different heights from the surface  31   a  of the wiring board  31 . That is, the first parallel portions  70   a  of the signal terminals are located at different heights, respectively. The joint portions  70   b  of the signal terminals are located at three different distances from the second side  60   b  of the housing  60  in the width direction of the housing  60 . Specifically, the joint portions  70   b  of the upper two signal terminals are located at the same distance from the second side  60   b,  the joint portions  70   b  of the middle two signal terminals are located at the same distance from the second side  60   b,  and the joint portions  70   b  of the lower two signal terminals are located at the same distance from the second side  60   b.    
   The signal terminals are classified into first, second, and third terminals  80 - 82  according to the distance of the joint portion  70   b  from the second side  60   b.  Each first parallel portion  70   a  of the first terminal  80  is located farther from the surface  31  a than each first parallel portions  70   a  of the second terminal  81 . Each first parallel portion  70   a  of the second terminal  81  is located farther from the surface  31  a than each first parallel portions  70   a  of the third terminal  82 . Each joint portion  70   b  of the third terminal  82  has a straight portion and a C-shaped portion. The straight portion is joined to the first parallel portion  70   a,  supported by the housing  60 , and extends perpendicular to the surface  31   a.  The C-shaped portion is exposed outside the housing  60 , located closer to the second side  60   b  of the housing  60  than the straight portion, and joined between the straight portion and the second parallel portion  70   c.  In such an approach, the length of the third terminal  82  is increased so that the connection reliability between the third terminal  82  and lands  40  can be improved. Further, a vertex  70   g  of the C-shaped portion is thinned. The thinned vertex  70   g  reduces stress applied to the solder joint between the third terminal  70  and the land  40  so that the connection reliability between the third terminal  70  and the land  40  can be improved. Since only the vertex  70   g  is thinned, an increase in impedance of the third terminal  82  is kept as low as possible. The first and second terminals can have the C-shaped portion, for example, between the first joint portion  70   b  and the second parallel portion  70   c.    
   In the embodiment, the joint portions  70   b  are arranged in the width direction of the housing  60  to from a zigzag arrangement. Alternatively, the joint portions  70   b  can be arranged in a manner other than a zigzag manner. For example, the joint portions  70   b  can be arranged in a grid manner. 
   The through hole  33  can be replaced with a blind hole that is not exposed to a back surface, opposite to the surface  31   a,  of the wiring board  31 . 
   Such changes and modifications are to be understood as being within the scope of the present invention as defined by the appended claims.