Patent Publication Number: US-8974244-B2

Title: Connector

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a connector to be connected to a board connector fixed to the upper surface of a board by soldering. 
     2. Description of the Related Art 
     A board connector device disclosed Japanese Unexamined Patent Publication No. 2007-87903 is known as an example of a board connector device of this type. The board connector includes a male housing including a receptacle with an open front surface and is structured such that tab-shaped terminal fittings are accommodated in this male housing while one ends are soldered to conductive paths of a board and the other ends are located in the receptacle and metal fixtures are mounted on both left and right side surfaces of the male housing. The board connector is fixed to the upper surface of an end edge part of the board by soldering the both metal fixtures. On the other hand, a connector to be connected to the board connector is connected to an end of a wiring harness. Specifically, this connector includes a female housing into which female terminals connected to ends of a plurality of wires are inserted and accommodated from behind. By fitting this female housing into the receptacle of the male housing of the board connector, the male and female terminal fittings are connected. 
     Since the wires are drawn out from the rear surface of the connector (female housing) in the board connector device as described above, the male housing of the board connector is pulled and, accordingly, an excessive stress may act on soldered parts of the metal fixtures and the soldered parts may be cracked or finally broken if, for example, the wires are pulled upward during wire laying or the like. 
     The present invention was completed based on the above situation and aims to prevent the action of an excessive stress on soldered parts of metal fixtures in a board connector. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a connector to be connected to a board connector including a receptacle and metal fixtures provided on opposite side surfaces and fixed to the upper surface of a board by soldering, comprising a housing connected to an end of a wiring harness and fittable into the receptacle of the board connector; and a holder formed separately from the housing, wherein the holder includes a lock member which is resiliently engaged with the housing to lock the holder in a state mounted on the holder and a locking portion which is engaged with the lower surface of the board when the housing is fitted into the receptacle of the board connector after the holder is mounted on the housing. 
     When the housing is fitted into the receptacle of the board connector with the holder mounted on the housing, the locking portion provided in the holder is engaged with the lower surface of the board. Thus, even if wires drawn out backward from the connector are pulled upwardly of the board, the locking portion is engaged with the board, thereby restricting the inclination of the housing and, further, the board connector and eventually preventing an excessive stress from acting on soldered parts of the metal fixtures. 
     Since the holder is formed separately from the housing and the lock member is provided only in the holder, it is sufficient to create only a manufacturing mold for the holder anew with a manufacturing mold for the housing kept as it is. Thus, this configuration can be inexpensively dealt with. 
     The locking portion may be capable of sandwiching the board from upper and lower sides. 
     The housing and, eventually, the board connector may be possibly inclined also when the wiring harness is pulled downwardly of the board depending on conditions such as when the receptacle of the board connector largely projects from an end edge of the board. However, since the locking portion provided in the holder is capable of sandwiching the board from both upper and lower sides, downward inclination can also be restricted. 
     The holder may be in the form of a frame fittable onto the housing from front and includes a contact portion which restricts a pushing operation by coming into contact with a contacted portion set on the housing and a lock arm which is resiliently engaged with the rear surface of the housing to retain the holder when the contact portion comes into contact with the contacted portion. 
     When the frame-shaped holder is fitted onto the housing from front and pushed, the pushing operation is stopped by the contact of the contact portion with the mating contacted portion when the holder is pushed to a proper position. At that time, the lock arm is resiliently engaged with the rear surface of the housing to retain the holder, whereby the holder is locked in a state mounted at the proper position on the housing. 
     A retainer mount hole into which a retainer for locking and retaining terminal fittings accommodated in the housing is to be mounted may be formed in a side surface of the housing. 
     If the locking portion provided in the holder is structured to be integral with the housing, the arrangement position of a so-called side retainer is restricted to avoid interference when the side retainer is mounted into the housing. However, since the locking portion is provided in the holder separate from and mounted later on the housing, a degree of freedom in design for the arrangement position of the side retainer can be drastically widened. 
     According to the present invention, it is possible to prevent the action of an excessive stress on soldered parts of metal fixtures in a board connector. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a side view in section showing an operation of connecting a harness-side connector according to one embodiment of the present invention to a board connector. 
         FIG. 2  is a perspective view showing a state where the board connector is fixed on a board. 
         FIG. 3  is a rear view of the board connector. 
         FIG. 4  is an exploded side view in section of the harness-side connector. 
         FIG. 5  is a plan view of a female housing and a holder. 
         FIG. 6  is a side view of the female housing and the holder. 
         FIG. 7  is a front view of the female housing. 
         FIG. 8  is a perspective view of the holder when viewed from behind. 
         FIG. 9  is a rear view of the holder. 
         FIG. 10  is a side view in section showing a state where the harness-side connector is connected to the board connector. 
         FIG. 11  is a side view showing the state of  FIG. 10 . 
         FIG. 12  is a perspective view showing a reinforcing structure of a male housing. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     One embodiment of the present invention is described with reference to  FIGS. 1 to 11 . 
     In this embodiment, as shown in  FIG. 1 , a harness-side connector  30  (corresponding to a connector of the present invention) connected to an end of a wiring harness is illustrated to be connected to a board connector  10  fixed to an end edge part of a printed wiring board P (hereinafter, merely referred to as a board P). 
     As shown in  FIGS. 1 to 3 , the board connector  10  includes a male housing  11  made of synthetic resin. This male housing  11  includes a receptacle  12  in the form of a flat rectangular tube with an open front surface, and a thick rear wall of this receptacle  12  serves as a terminal holding portion  13 . 
     A plurality of terminal fittings  15  are mounted through the terminal holding portion  13  while being arranged in a lateral direction in two upper and lower levels. The terminal fittings  15  are formed by bending tabs into a crank shape and there are two types of larger and smaller terminal fittings  15  which mainly differ in thickness. 
     Each terminal fitting  15  is mounted into a terminal press-fitting opening  14  formed in the above terminal holding portion  13  by being press-fitted thereinto from behind. Terminal connecting portions  16  of the respective terminal fittings  15  on one end side project into receptacle  12  and are arranged in the lateral direction in the two upper and lower levels, and board connecting portions  17  on the other end side are arranged side by side and respectively connected to corresponding conductive paths formed on the board P by soldering. 
     Fixtures  20  are mounted on both left and right surfaces of the male housing  11 . Each metal fixture  20  is so formed by bending a metal plate into a substantially L shape that a mounting plate  22  bent outward at a right angle is formed at a lower end part of the main plate  21 . On the other hand, mounting grooves  25  are so formed in the both left and right surfaces of the male housing  11  as to vertically penetrate, and the metal fixtures  20  are retained and fixed by press-fitting both lateral edges of the main plates  21  of the metal fixtures  20  along both lateral edges of the mounting grooves  25 . At this time, the mounting plates  22  of the metal fixtures  20  are located slightly below the lower surface of the male housing  11  and fixed to fixing lands provided on the board P. 
     A lock protrusion  27  is formed at a widthwise center position of the front edge of the ceiling wall of the receptacle  12  of the male housing  11 . Further, the inner surfaces of opposite side walls are cut at lower positions to form guide grooves  28  extending from the front edges. 
     As shown in  FIGS. 4 to 6 , the harness-side connector  30  is composed of a female housing  31  and a holder  50 . 
     The female housing  31  is made of synthetic resin and in the form of a flat and laterally long block as also shown in  FIG. 7 . A substantially ⅔ length area of the female housing  31  on the front side is fittable into the receptacle  12  of the male housing  11  of the board connector  10  described above. 
     A plurality of cavities  32  penetrating in forward and backward directions are formed side by side in the lateral direction in two upper and lower levels in conformity with the arrangement of the terminal connecting portions  16  of the terminal fittings  15  mounted in the above board connector  10 . There are also two types of larger and smaller cavities  32 , which are arranged at positions corresponding to the larger and smaller terminal fittings  15  of the board connector  10 . 
     Female terminals  35  connected to ends of wires  34  are accommodated into the respective cavities  32  and there are also two larger and smaller types of female terminals  35 . As shown by an arrow a of  FIG. 4 , the female terminal  35  is inserted into the corresponding cavity  32  from behind and is resiliently engaged with a locking lance  33  provided at the bottom surface of the cavity  32  to be retained when being inserted to a proper position. 
     A side-type retainer for doubly locking the female terminals  35  is mounted in a lower side of the female housing  31 . Thus, a retainer mount hole  38  is formed to penetrate through the respective cavities  32  substantially over the entire width at a center position of the lower surface of the female housing  31  in forward and backward directions. 
     The retainer  37  is likewise made of synthetic resin and, as a whole, in the form of a lattice tightly insertable into the retainer mount hole  38  described above from below, and locking protrusions  37 A to be engaged with engaging portions  35 A (jaw portions) of the female terminals  35  are arranged in correspondence with the arrangement of the cavities  32 . As shown in  FIG. 4 , the retainer  37  can be mounted at a partial locking position where the respective locking protrusions  37 A are retracted downward from the cavities  32  to permit the insertion of the female terminals  35  as shown in  FIG. 4  and a full locking position where the respective locking protrusions  37 A are located in the cavities  32  to be engageable with the female terminals  35  as shown in  FIG. 1 . 
     A lock lever  40  including a projection  41  to be engaged with the lock protrusion  27  of the male housing  11  of the board connector  10  is resiliently displaceably provided while extending backward from the front edge at a widthwise central part of the upper surface of the female housing  31 . The extending end of the lock lever  40  serves as an operating portion  42 , and the lock lever  40  can be forcibly resiliently displaced by pressing this operating portion  42 . 
     As shown in  FIG. 7 , a flange  44  is formed over the entire circumference on the rear surface of the female housing  31 . An upper flange  44 A of this is so formed that an upper end part of a widthwise central part bulges out forward to form a protection wall  45  crossing an upper part of a front end side of the operating portion  42  of the lock lever  40 . On the other hand, protection walls  46  stand at both left and right sides of the lock lever  40 . These protection walls  45 ,  46  protect the lock lever  40  from entanglement with the wires  34  and the like. 
     A lower flange of the flange  44  serves as a finger placing portion  46 . By placing fingers on this finger placing portion  46 , it is facilitated to press the operating portion  42  of the above lock lever  40  and subsequently pull the female housing  31 . 
     Guide ribs  47  which project from the front surfaces of left and right flanges  44 B and are insertable into the guide grooves  28  formed on the inner surfaces of the opposite side walls of the mating male housing  11  are formed on rear edge parts of the left and right outer surfaces of the female housing  31 . 
     The holder  50  formed separately from the female housing  31  is mountable onto this female housing  31 . 
     The holder  50  is likewise made of synthetic resin and roughly in the form of a laterally long rectangular frame with depth so as to be fittable on a rear end side of the female housing  31  as also shown in  FIG. 8 . An escaping recess  51  into which the protection wall  45  of the female housing  31  is to be fitted and allowed to escape is formed in a widthwise central part of the rear edge of the ceiling wall of the holder  50 . 
     Further, a rear wall  52  projecting inwardly a predetermined distance is formed on the inner peripheral edge of the rear end of the holder  50 . Note that a lower side  52 A of the rear wall is tall and a lower area is recessed into a stepped shape. 
     Contact portions  54 A to  54 C which substantially come into contact with the flange  44  of the female housing  31  to prevent the holder  50  from being pushed any further when the holder  50  is fitted onto the female housing  31  from front are formed on the rear wall  52  of the holder  50  as specifically described later. 
     More specifically, a pair of laterally long left and right first contact portions  54 A which come into contact with the upper flange  44 A are formed on an upper side of the rear wall  53 . Short second contact portions  54 B which come into contact with the left and right flanges  44 B are formed on left and right sides of the rear wall  52 . The both second contact portions  54 B are formed with escaping grooves  55  into which the guide ribs  47  formed on the left and right outer surfaces of the female housing  31  are inserted and allowed to escape. A third contact portion  54 C which comes into contact with the lower flange, i.e. the finger placing portion  46  is formed substantially over the entire width in an upper area of the lower side  52 A of the rear wall. Respective parts of the flange  44  of the female housing  31  with which these contact portions  54 A to  54 C come into contact serve as a contacted portion of the present invention. 
     Resiliently displaceable lock arms  57 A,  57 B which are engaged with the female housing  31  to retain the holder  50  when the holder  50  is pushed onto the female housing  31  up to a proper position and stopped project from the rear surface of the holder  50 . 
     The two first lock arms  57 A are formed to project at positions above the second contact portions  54 B on the left and right sides of the rear wall  52  of the holder  50 , and hook portions  58  on the leading ends are engaged with the rear surfaces of the left and right flanges  44 B of the female housing  31  at upper positions. 
     On the other hand, the two second lock arms  57 B are likewise formed to project from opposite left and right ends of a lower area of the lower side  52 A of the rear wall and hook portions  58  on the leading ends are respectively engaged with the rear surface of the finger placing portion  46  formed on the lower end of the rear surface of the female housing  31  at positions near the left and right ends of the finger placing portion  46 . 
     Board insertion grooves  60  into which end edges of the board P are substantially tightly inserted are formed at lower positions of the front edges of the left and right walls of the holder  50 . Specifically, the board insertion grooves  60  are formed to extend in a depth direction from the front edges of the side walls at positions flush with the upper surface of the lower wall of the holder  50 , and have such a depth that the end edges of the board P reach the back ends when the female housing  31  mounted with the holder  50  is properly fitted into the receptacle  12  of the mating male housing  11  as specifically described later. 
     By forming the board insertion grooves  60  as described above, the lower wall of the holder  50  over the entire width functions as a lower locking portion  61  to be engaged with the lower surface of the board P. On the other hand, upper edge parts of the board insertion grooves  60  in the side walls of the holder  50  function as upper locking portions  62  to be engaged with the upper surface of the board P. 
     Next, functions of this embodiment are described. 
     As shown in  FIGS. 1 and 2 , the board connector  10  is placed and surface-mounted on the board P at a predetermined position near an end edge of the board P such that a leading end part of the male housing  11  projects a predetermined distance from the end edge of the board P, and the board connecting portions  17  of the respective terminal fittings  15  are connected to the corresponding conductive paths by soldering and the mounting plates  22  of the left and right metal fixtures  20  are fixed to the board P by soldering. 
     In the harness-side connector  30 , as shown in  FIG. 4 , the female terminal  35  connected to the end of the wire  34  is inserted into each cavity  32  provided in the female housing  31  from behind and primarily locked by the locking lance  33  with the retainer  37  held at the partial locking position. Subsequently, the retainer  37  is pushed to the full locking position, whereby the respective female terminals  35  are doubly locked (see  FIG. 1 ). Here, the wires  34  drawn out from the rear surface of the female housing  31  are appropriately bundled to form a wiring harness. 
     Subsequently, the holder  50  is fitted onto the female housing  31  in which the female terminals  35  are accommodated and doubly locked as described above as shown by an arrow b of  FIG. 4 . When the holder  50  is pushed and this pushing operation comes to a final stage, the guide ribs  47  are inserted into and guided by the escaping grooves  55  and the holder  50  is pushed while the respective lock arms  57 A,  57 B come into contact with the left and right flanges  44 B and the finger placing portion  46  to be resiliently deformed. The pushing operation is stopped when the contact portions  54 A to  54 C of the holder  50  come into contact with the contacted portions set on the flange  44  of the female housing  31 . At this time, the hook portions  58  of the lock arms  57 A,  57 B pass the left and right flanges  44 B and the finger placing portion  46 , whereby the lock arms  57 A,  57 B are engaged with the left and right flanges  44 B and the finger placing portion  46  while being restored and displaced. In this way, the holder  50  is mounted at a proper position on a rear end part of the female housing  30  as shown in  FIG. 1 . 
     The harness-side connector  30  assembled in this way is connected to the board connector  10  as shown by an arrow c of  FIG. 1 . Specifically, the female housing  31  is fitted into the receptacle  12  of the mating male housing  11 . As the harness-side connector  30  is pushed in, the leading end side of the receptacle  12  enters the holder  50  and the lock lever  40  is resiliently deformed. When the harness-side connector  30  is pushed to a proper position where the leading end of the female housing  31  comes into contact with the terminal holding portion  13 , the male and female housings  11 ,  31  are locked in a properly connected state while the lock lever  40  is restored and displaced as shown in  FIG. 10 . This causes the corresponding terminal fittings  15  and female terminals  35  to be properly electrically connected. 
     Further, during this time, the end edges of the board P are inserted into the board insertion grooves  60  provided in the holder  50 . When the two housings  11 ,  31  are properly connected, the end edges reach the back ends of the board insertion grooves  60 . 
     Even if a bundle of wires  34  (wiring harness) drawn out backward from the harness-side connector  30  is pulled, for example, upward as shown by an arrow x of  FIG. 11  in a state where the connection of the two connectors  10 ,  30  is completed as shown in  FIG. 11 , the lower locking portion  61  provided in the holder  50  is engaged with the lower end edge of the board P over a wide range, thereby restricting the inclination of the female housing  31  and, further, the board connector  10  connected thereto and eventually preventing an excessive stress from acting on soldered parts of the metal fixtures  20 . 
     Further, if the bundle of wires  34  (wiring harness) is pulled downward as shown by an arrow y of  FIG. 11 , the female housing  31  is more or less inclined in a clockwise direction of  FIG. 11 , but the left and right upper locking portions  62  are engaged with the end edges of the upper surface of the board P, thereby more reliably restricting the inclination of the female housing  31  and, further, the board connector  10  connected thereto in the clockwise direction. 
     As described above, according to this embodiment, the holder  50  mounted on the harness-side connector  30  includes the board insertion grooves  60  into which the end edges of the board P are inserted when the connector  30  is properly connected to the mating board connector  10 , and the end edges of the board P are sandwiched by the locking portions  61 ,  62  provided at the lower and upper sides of the board insertion grooves  60 . Thus, even if the bundle of the wires  34  (wiring harness) drawn out backward from the harness-side connector  30  is pulled upward or downward, the locking portions  61 ,  62  are engaged with the board P, thereby restricting the inclination of the female housing  31  and, further, the mating board connector  10  and eventually preventing an excessive stress from acting on the soldered parts of the metal fixtures  20 . 
     Thus, a situation can be prevented where the soldered parts of the metal fixtures  20  are broken, the board connector  10  is displaced and eventually soldered parts of the terminal fittings  15  are damaged. 
     Since the holder  50  including the locking portions  61 ,  62  is formed separately from the female housing  31  and the lock arms  57 A,  57 B are provided only on the holder  50 , it is sufficient to create only a manufacturing mold for the holder  50  anew with a manufacturing mold for the female housing  31  kept as it is. This configuration can be inexpensively dealt with. 
     If the locking portions  61 ,  62  provided in the holder  50  are structured to be integral with the female housing  31 , the side-type retainer  37  cannot be mounted into the female housing  31  or the arrangement position thereof is restricted due to a possibility of interfering with the locking portions  61 ,  62 . However, since the locking portions  61 ,  62  are provided in the holder  50  formed separately from and mounted later on the female housing  31 , the arrangement position of the side-type retainer  37  can be arbitrarily set. 
     Note that the following structure may be adopted as a related technology. 
     The board connector  10  tends to be made thinner due to a height reduction request. In such a case, if the wires  34  drawn out from the mating harness-side connector  30  are pulled upward to incline this connector  30 , the upper surface of the thinned receptacle  12  may be broken. 
     As an example of a measure to prevent this, a high-strength film  70  or a metal film may be bonded to the upper surface of the receptacle  12  to reinforce the upper surface as shown in  FIG. 12 . Since reinforcement is made by a separate part, the need for a design change of the male housing  11  in the board connector  10  can be eliminated. 
     The present invention is not limited to the above described and illustrated embodiment. For example, the following embodiments are also included in the technical scope of the present invention. 
     The positions of the board insertion grooves provided in the holder are not limited to the positions illustrated in the above embodiment and may, for example, be other positions such as intermediate positions of the side walls in the height direction. Even at the intermediate positions of the side walls in the height direction, locking portions for sandwiching the board can be formed at both upper and lower sides of the board insertion grooves. 
     Out of the locking portions provided in the holder, the upper locking portions to be engaged with the upper surface of the board may be omitted. Such a configuration is also included in the technical scope of the present invention. 
     The shapes and arrangement positions of the contact portions provided on the holder to stop the pushing operation can be arbitrary shapes and arbitrary positions as long as the contact portions are provided on existing parts of the female housing. 
     The shapes and arrangement positions of the lock arms provided on the holder to retain the holder can be arbitrary shapes and arbitrary positions as long as the lock arms can be engaged with existing parts of the female housing. 
     Although the holder is substantially in the form of a frame and fitted and mounted onto the female housing from front in the above embodiment, the shape and mounting method of the holder can be arbitrarily set according to conditions such as the shape of the female housing.