Patent Publication Number: US-8529292-B2

Title: Board connector having a housing with a mounting groove with upwardly facing surfaces for receiving projecting locks of a mounting fixture

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a board connector. 
     2. Description of the Related Art 
     U.S. Pat. No. 7,134,910 discloses a board connector with a synthetic resin housing configured to receive a mating connector from the front. Mounting grooves are formed on side surfaces of the housing. Fixtures are mounted in mounting grooves and lower end portions of the fixtures are fixed to a circuit board by soldering. More specifically, the fixtures are formed by press-working a metal plate. Locks are formed at upper end portions of each fixture and project laterally from the opposite lateral edges. On the other hand, the mounting grooves each are formed to have a stepped shape with a widened upper end. The fixture is inserted into the mounting groove from above along the side surface of the housing, and a part of the fixture below the locks is pushed and press-fit into a narrow part of the mounting groove. This pushing operation is stopped when the locks contact step surfaces of the mounting groove. In this way, the fixtures are mounted while downward movements with respect to the housing are prevented. Thus, when the fixtures are fixed to the circuit board, the step surfaces of the mounting grooves are engaged with the locks of the fixtures to prevent upward detachment of the housing. 
     The above-described board connector is mounted on the circuit board and used with a mating connector that is fit in the housing. A wiring harness pulled vertically out from the mating connector may move due to vibration or the like and the wiring harness could be pulled up during use. Thus, a force acts to tear the housing from the circuit board and the front step surfaces formed in the mounting grooves are mainly engaged with the front locks on the fixtures to prevent the housing from being torn from the circuit board. 
     On the other hand, there is a tendency to thin the fixtures for weight saving and the like. If a large force acts on the housing in a direction to tear the housing, the locking portions may be deformed and bent so that engagement areas with the step surfaces are reduced. Therefore, the locks may disengage from the step surfaces and the synthetic resin step surfaces may be scraped away. 
     The invention was developed in view of the above situation and an object thereof is to increase fixing strength of a board connector to a board. 
     SUMMARY OF THE INVENTION 
     The invention relates to a board connector, comprising: a housing into which a mating connector can be fit from the front. At least one mounting groove is formed on at least one side surface of the housing. The board connector also has at least one fixture that can be mounted into the mounting groove along an inserting direction. The fixture has a plate surface that moves substantially along the side surface of the housing and a distal end portion that is to be fixed to a board. At least one projecting lock projects laterally substantially along the plate surface and at least one bent lock is bent out at an angle with respect to the plate surface. The projecting lock and the bent lock are arranged one above the other along the inserting direction on a lateral edge of the fixing fixture. The mounting groove includes receiving surfaces that contact the projecting lock and the bent lock to prevent further insertion of the locks. 
     The fixture preferably is made of a metal plate material. 
     The fixture is mounted in the mounting groove with the projecting lock and the bent lock held in contact with the corresponding receiving surfaces. The receiving surfaces are engaged with the corresponding locks to prevent upward detachment of the housing when the fixture is fixed to the board. The two locks enable a load acting on the locks to be distributed, thereby preventing deformation of the locks and assuring a locking function. 
     The fixture would become wider if the two locks one above the other both were projecting. Accordingly, the width of the mounting groove and, therefore, the depth of the housing would be increased. However, one lock of the fixture of the invention is bent to suppress the width enlargement of the fixture and the mounting groove. Therefore, the bent lock avoids the need to enlarge the housing. As a result, fixing strength of the board connector to the board is increased without enlarging the housing. 
     The projecting lock may be above (or behind as seen in the inserting direction) the bent lock. Thus, a large engagement area of the projecting lock with the receiving surface is ensured while the outer surface of the bent lock is held in contact with the groove bottom of the mounting groove as not to shake. 
     At least one reinforcing bead may be provided on the fixture. The reinforcing bead may extend in a direction intersecting the inserting direction and may be at a height position of the fixture substantially corresponding to a formation position of the bent lock. The reinforcing bead may be horizontal. The reinforcing bead increases rigidity of a bent part of the bent lock and reliably prevents deformation of the bent lock. 
     At least one mounting plate may be provided at a distal end portion of the fixing fixture and may be bent out at an angle, preferably substantially a right angle, with respect to the plate surface. The mounting is to be fixed to the board preferably by soldering. 
     These and other objects, features and advantages of the invention will become more apparent upon reading the following detailed description of preferred embodiments and accompanying drawings. It should be understood that even though embodiments are described separately, single features thereof may be combined to additional embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view in section showing an operation of connecting a harness-side connector to a board connector according to one embodiment of the invention. 
         FIG. 2  is a perspective view of a housing of the board connector. 
         FIG. 3  is a side view showing an operation of inserting a fixture into a mounting groove of the housing. 
         FIG. 4  is a plan view of the housing and the fixture. 
         FIG. 5  is a section along A-A of  FIG. 4 . 
         FIG. 6  is a section along B-B of  FIG. 4 . 
         FIG. 7  is a perspective view of the fixture. 
         FIG. 8  is a partial plan view showing a state where the fixture is mounted in the mounting groove of the housing. 
         FIG. 9  is a section along A-A of  FIG. 4  showing a state where the fixture is mounted. 
         FIG. 10  is a section along B-B of  FIG. 4  showing the state of  FIG. 9 . 
         FIG. 11  is a side view showing a state where the harness-side connector is connected to the board connector. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A board connector in accordance with the invention is identified by the numeral  10  in  FIG. 1 . The board connector  10  is to be fixed or mounted to an end part of an electric device or a board. such as a printed circuit board P and a harness-side connector  50  connected to an end of a wiring harness WH is connected to the board connector  10  from the front. 
     The board connector  10  includes a housing  20  made e.g. of synthetic resin and having terminal fittings  11  accommodated therein. Two fixtures  40  are mounted on opposite side surfaces of the housing  20  and are fixed to the board P by soldering, bolting, gluing or the like. 
     As also shown in  FIG. 2 , the housing  20  is substantially is in the form of a wide block and a receptacle  21  is formed at its front end for receiving the housing-side connector  50 . Terminal insertion holes  23  are formed in upper and lower stages in a base wall  22  of the housing  20  at the back of the receptacle  21 . Terminal connecting portions  12  at one ends of the terminal fittings  11  are inserted into the respective terminal insertion holes  23  and project in an array into the receptacle  21 . 
     The other end of each terminal fitting  11  projects back from the base wall  22  and is bent down at a substantially right angle at a specified position, and a lower end portion that reaches the lower surface of the housing  20  is bent further back at a substantially right angle to define a board connecting portion  13 . The board connecting portion  13  of each terminal fitting  11  is soldered or otherwise connected to a corresponding conductive path on the board P when the housing  20  is placed at a specified position on the board P. 
     Each fixture  40  is formed by press-working a metal plate and includes a main plate  41  to be mounted on the side surface of the housing  20  and a mounting plate  42  bent out at a substantially right angle from the lower end of the main plate  41  and is to be placed on the board P. Thus, the fixture  40  is substantially L-shaped, as shown in  FIGS. 3 ,  4  and  7 . 
     As shown in  FIG. 3 , the main plate  41  has a stepped shape with a wide upper portion  41 A and a narrow lower portion  41 B. Note that a lower area of the narrow portion  41 B has a stepped shape by bulging out by a distance that is about half the thickness. 
     Three locks  43 ,  44  and  45  are formed on each of the opposite left and right edges of the wide portion  41 A of the main plate  41  while being spaced apart in a vertical direction and being substantially bilaterally symmetrical. 
     First projecting locks  43  are formed at an upper end position and project laterally a relatively long distance to substantially extend along the plate surface of the main plate  41 . Biting projections  43 A are formed on the projecting edges of the first projecting locks  43 . 
     Bent locks  44  are formed at an intermediate or center position in a height direction and are bent out at substantially right angles with respect to the plate surface of the main plate  41 . 
     Second projecting locks  45  are formed at a lower end position and project out laterally a relatively short distance along the plate surface of the main plate  41 . The positions of the projecting edges of the second projecting locks  45  are equivalent to those of the outer surfaces of the bent locks  44 , and biting projections  45 A are formed on these projecting edges. 
     At least one substantially horizontal reinforcing bead  46  is formed substantially over the entire width at a height position of the wide portion  41 A of the main plate  41  substantially corresponding to formation positions of the bent locks  44 . 
     A slit  47  is formed at a widthwise center position in an area extending from the mounting plate  42  to the narrow portion  41 B of the main plate  41  of each fixture  40 , and two solder insertion holes  48  are formed in each divided part of the mounting plate  42  and a solder insertion groove  49  is formed in the projecting edge of each divided part. 
     Mounting grooves  30  are formed on the opposite side surfaces of the housing  20  as shown in  FIGS. 2 to 4 , and the respective fixtures  40  are insertable therein from above. Thus, front and rear walls  26  bulge out on each of the opposite side surfaces of the housing  20 . Both walls  26  have a height longer than the entire length of the fixture  40  and a width that is several times (particularly more than about twice, more specifically more than about three times, e.g. about seven times) as large as the thickness of the fixture  40 , and vertical surfaces  27  thereof substantially facing each other are spaced apart by a distance substantially equal to the width of the narrow portion  41 B of the main plate  41  of the fixture  40 . 
     The above mounting groove  30  is formed between the facing surfaces  27  of the walls  26 . Specifically, a back side groove  31 , into which the main plate  41  of the fixture  40  is closely insertable or fittable, is formed at a back side position on the side surface of the housing  20  between the facing surfaces  27  of the both walls  26 . As shown in  FIGS. 5 and 9 , the back side groove  31  has a stepped shape that narrows toward a bottom side in a stepped manner to have at least three stages. An upper stage  32  has a width to closely accommodate the bulging edges of the first projecting locks  43 , an intermediate stage  33  has a width to accommodate the projecting edges of the second projecting locks  45  and the outer surfaces of the both bent locking portions  44  and a lower stage  34  has a width to substantially equal to the spacing between the facing surfaces  27  and slightly longer than the width of the narrow portion  41 B of the main plate  41 . 
     The groove bottoms of upper sides of the upper stage  32  define tapered surfaces  32 A to widen the upper stage  32  toward the top for a guiding purpose. 
     Steps between the upper stage  32  and the intermediate stage  33  in the back side groove  31  define first receiving surfaces  35  for receiving the lower surfaces of the first projecting locks  43 , and steps between the intermediate stage  33  and the lower stage  34  define second receiving surfaces  36  for receiving the lower surfaces of the second projecting locks  45 . 
     A groove  37  is formed at a side before the back side groove  31  between the facing surfaces  27  of the walls  26  and communicates with the back side groove  31  to allow insertion of the bent locks  44  of the fixture  40 . The groove bottoms (side surfaces) of the vertical groove  37  are substantially flush with the groove bottoms (side surfaces) of the intermediate stage  33  of the back side groove  31  and are formed from the upper surfaces substantially to a position slightly lower than central height positions of the facing surfaces  27 . The bottom surfaces of this vertical groove  37  define third receiving surfaces  38  for receiving the lower surfaces of the bent locks  44 . These third receiving surfaces  38  are at a specified distance from the second receiving surfaces  36  of the back side groove  31 . 
     The fixture  40  is to be inserted into the mounting groove  30  from above and along an inserting direction ID as shown by an arrow of  FIG. 3 . Although described in detail later, the first and second projecting locks  43  and  45  at the lateral edges of the main plate  41  are press-fit respectively into the upper and intermediate stages  32  and  33  of the back side groove  31 , and the bent locks  44  are pushed while being inserted into the vertical groove  37 . The first and second projecting locks  43 ,  45  respectively contact the first and second receiving surfaces  35 ,  36  of the back side groove  31  and the bent locks  44  contact the third receiving surfaces  38  at the bottom of the vertical groove  37  when the mounting plate  42  is pushed to a position slightly above the lower surface of the housing  20 , thereby preventing any further pushing movement of the fixing fixture  40 . 
     As shown in  FIG. 1 , the housing-side connector  50  has a synthetic resin housing  51  that can fit in the receptacle  21  of the housing  20  of the board connector  10 . Cavities  52  in the housing  51  define an array corresponding to the terminal connecting portions  12  of the terminal fittings  11  of the board connector  10 . Female terminals  53  connected to ends of wires W are inserted into the cavities  52  from behind, and are locked primarily by locking lances  54  in the cavities  52  and secondarily by a retainer  55 . 
     A lock lever  57  is provided at the upper surface of the housing  50  for resiliently locking a lock projection  25  of the housing  20  of the board connector  10 . 
     The terminal fittings  11  are mounted into the housing  20  and the fixtures  40  are mounted into the respective mounting grooves  30  at the opposite side surfaces. More specifically, the fixtures  40  are inserted into the mounting grooves  30  from above and along the inserting direction ID, as shown by the arrow of  FIG. 3 , while the main plates  41  move along the side surfaces of the housing  20 . The fixtures  40  are pushed while the first and second and first projecting locks  43 ,  45  on the left and right edges of the main plates  41  are press-fit into the upper and intermediate stages  32  and  33  of the back side grooves  31  and the bent locks  44  are inserted into the vertical grooves  37 . The first and second projecting locks  43 ,  45  shown in  FIG. 9  respectively contact the first and second receiving surfaces  35 ,  36  of the back side grooves  31  and the bent locks  44  contact the third receiving surfaces  38  of the vertical grooves  37 , as shown in  FIG. 10 , when the mounting plates  42  are pushed to the positions slightly above the lower surface of the housing  20 . 
     During this time, the biting projections  43 A of the first projecting locks  43  and the biting projections  45 A of the second projecting locks  45  bite into the groove bottoms of the upper stages  32  and the middle or intermediate stages  33  of the back side grooves  31 , so that the fixtures  40  are retained and mounted in the mounting grooves  30 . 
     The assembled board connector  10  is placed at a specified position on the board P so that the front end of the housing  20  projects a specified distance from the end edge of the board P, as shown in  FIGS. 1 and 11 . The board connecting portions  13  of the respective terminal fittings  11  then are connected electrically (e.g. soldered) to the corresponding conductive paths by surface mounting, and the mounting plates  42  of the left and right fixtures  40  are connected to the board P by soldering, bolting, gluing or the like. 
     The mating housing-side connector  50  is inserted into the receptacle  21  of the housing  20  of the board connector  10  mounted on the board P, as shown by an arrow of  FIG. 1 . The lock lever  57  engages with the lock projection  25  when the housing-side connector  50  is fit to a proper position so that the two connectors  10 ,  50  are locked in a properly connected state and, accordingly, the corresponding terminal fittings  11  and female terminals  53  are connected electrically to each other. 
     The wiring harness WH pulled out from the housing-side connector  50  may move vertically due to vibration or the like or may be pulled up as shown by an arrow X of  FIG. 11  in a state where the two connectors  10 ,  50  are completely connected. Thus, a force acts to tear the front side of the housing  20  of the board connector  10  from the board P. In this case, the first, second and third receiving surfaces  35 ,  36  and  38  at the front side (right side in  FIGS. 9 and 10 ) mainly formed in the mounting grooves  30  are engaged with the first and second projecting locks  43  and  45  and the bent locks  44  formed on the front edges of the fixing fixtures  40 , thereby preventing the housing  20  from being torn. 
     The locks  43 ,  44  and  45  are arranged vertically one above another on each lateral edge of each fixture  40 . Thus, a load when a force acts on the housing  20  in a direction to tear the housing  20  from the board P is distributed among the respective locks  43 ,  44  and  45 . Therefore a locking function is assured by preventing deformation of the respective locks  43 ,  44  and  45  and ensuring sufficient engagement areas. 
     Further, in providing the plurality of (e.g. three) locks one above another, if all the locks are projecting, the fixtures  40  become wider and, accordingly, the width of the mounting grooves  30  and, therefore, the depth of the housing  20  need to be increased. On the contrary, in this embodiment, one lock  44  is bent. Thus, the width enlargement of the fixtures  40  can be suppressed and the width enlargement of the mounting grooves  30  and, therefore, the enlargement of the housing  20  can be suppressed. As a result, fixing strength of the board connector  10  to the board P can be improved without leading to the enlargement of the housing  20  and the like. 
     In a vertical arrangement relationship of the first projecting lock  43  and the bent lock  44 , a clearance has to be provided between the outer surface of the bent lock and the groove bottom of the mount groove in some cases to ensure a sufficient engagement area of the first projecting lock with the receiving surface if the bent lock is above the first projecting lock. In this respect, in this embodiment, by arranging the first projecting lock  43  above the bent lock  44 , a large engagement area of the first projecting lock  43  with the first receiving surface  35  can be ensured while the outer surface of the bent lock  44  is held in contact with the groove bottom of the vertical groove  37  so as not to shake. 
     Further, the rigidity of bent parts of the bent locks  44  is increased and, therefore, deformation of the bent locks  44  is prevented more reliably by forming the reinforcing bead  46  at the height position corresponding to the formation positions of the bent locks  44  on the main plate  41  of the fixing fixture  40 . 
     The invention is not limited to the above described and illustrated embodiment. For example, the following embodiments are also included in the scope of the invention. 
     It is sufficient to provide at least one projecting lock and one bent lock. 
     In the case of vertically arranging the projecting lock and the bent lock one above the other, which of them is located above does not matter. 
     A means for fixing the fixing fixtures to the board is not limited to soldering illustrated in the above embodiment and may be another means such as screw mounting, gluing or the like. 
     The fixing fixtures may be made of a material different from metal but having sufficient rigidity such as composite materials or the like.