Patent Publication Number: US-6341974-B1

Title: Connector with a partial connection preventing function

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a connector with a partial connection preventing function. 
     2. Description of the Related Art 
     A connector with a partial connection preventing mechanism is shown, for example, in Japanese Unexamined Patent Publication NO. 10-134890. This prior art connector is identified by the numeral  1  in FIGS. 6 and 7 below, and is provided with female and male housings  2  and  3 , which are connectable with each other. The female housing  2  has an upper surface with a locking piece  4  that is vertically elastically deformable. A pushing portion  5  projects from an upper surface of the locking piece  4  and can push a slidable member  13 , which is described later. Wing-like projections  6  are provided on the left and right edges of the locking piece  4 . Each projection  6  has a slanted guide surface  6 A on its front face. 
     The front surface of the male housing  3  is provided with a receptacle  8  into which the female housing  2  can be fit. Left and right guides  9  project from the upper surface of the receptacle  8 . The guides  9  have inwardly projecting engaging portions  10  for engaging the corresponding projections  6  of the locking piece  4 . Slanted guide surfaces  10 A,  10 B are formed at the front and rear ends of each engaging portion  10  for guiding the projections  6 . Further, a slide groove  11  extends into the rear of the upper surface of the male housing  3  and is configured to receive the slide  13 . The slide  13  has a substantially H-shaped cross section, and can be slid along forward and backward directions on the male housing  3  by holding the edges of the slide groove  11  in groove portions  14  at the left and right sides of the slide  13 . An upper part of the slide  13  projects upward from the upper surface of the male housing  3  and defines a pushable portion  15 . A finger-engageable operable projection  15 A projects at the rear end of the pushable portion  15  and a zigzag spring  16  is mounted behind the slide  13 , so that the slide  13  is constantly biased forward. A cover  17  is mounted on the male housing  3  for locking the slide  13  and the spring  16  against backward movement. 
     The prior art female housing  2  is fitted into the receptacle  8  of the prior art male housing  3  so that the guide surfaces  6 A of the left and right projections  6  of the locking pieces  4  contact the guide surfaces  10 A of the engaging portions  10 . As a result, the locking piece  4  deforms elastically upward to bring the pushing portion  5  into contact with the front end face of the slide  13 . The female housing  2  can be pushed further so that the pushing portion  5  compresses the spring  16  and pushes the slide  13  backward, as shown in FIG.  8 . When the projections  6  of the locking piece  4  move over the engaging portions  10 , the locking piece  4  is restored elastically to its original position to engage the projections  6  and the engaging portions  10 . The slide  13  then is returned forward to restrict deformation of the locking piece  4  in a disengaging direction (upward). As a result, the housings  2  and  3  are locked in their properly connected state. If the connecting operation of the prior art housings  2  and  3  is interrupted halfway, the pushing portion  5  of the locking piece  4  is biased by the slide  13 , thereby pushing the female housing  2  out. In this way, a partial connection is prevented. 
     To disconnect the properly connected prior art housings  2  and  3 , a finger is placed on the pushable portion  15  to push the slide  13  against a biasing force of the spring  16 . If the female housing  2  is withdrawn in this way, the projections  6  of the locking piece  4  move up along the guide surfaces  10 B of the engaging portions  10 , thereby elastically deforming the locking piece  4  upward. The housings  2  and  3  are separated upon completely withdrawing the female housing  2 . If the separating operation of the housings  2  and  3  is interrupted halfway, the spring  16  pushes the slide  13  against the pushing portion  5  of the locking piece  4  and urges the female housing  2  out. This prevents the housings  2  and  3  from being left partly connected. 
     The pushable portion  15  projects out from the outer surface of the prior art male housing  3 . Thus, an external matter may be struck against the pushable portion  15  to exert an external force on the slide  13 , or on portions of the housings  2 ,  3  near the pushable portion  15 , thereby deforming and/or damaging them. 
     In view of the above problem, an object of the present invention is to provide a connector that can prevent a projecting operable portion, such as a slide and their neighboring members, from being deformed and damaged. 
     SUMMARY OF THE INVENTION 
     The subject invention is directed to a connector that comprises first and second housings, each of which has a front side. The housings are at least partly connectable with each other at their front sides. A slide is provided at least partly in the first housing, and can be slid in the connecting directions of the housings. Additionally, the slide is biased forward in the first housing by a biasing means. A locking piece is provided in the second housing and can engage an engaging portion to hold the housings in a properly connected condition. The slide can interact with the locking piece to restrict movement of the locking piece in a disengaging direction from the engaging portion. A pushable portion projects from the slide, and is operable to push the slide up to a position where a disengaging movement of the locking piece from the engaging portion is permitted. The pushable portion does not project out from the outer surface of the first housing, and therefore, is not likely to be struck by external matter. 
     According to a preferred embodiment, the locking piece is elastically displaceable in a direction substantially normal to the connecting directions of the housings. Additionally, the locking piece pushes the slide against the biasing means while the housings are being connected, and then moves onto the engaging portion that projects in the first housing. The locking piece moves over the engaging portion when the housings are properly connected, and then the locking piece is restored elastically to engage the engaging portion and hold the housings in a properly connected condition. 
     A biasing force of the biasing means moves the slide forward as the locking piece is restored elastically to its locking position. The sliding member also may be restored elastically and positioned substantially outside the locking piece to restrict elastic deformation of the locking piece in a disengaging direction from the engaging portion. 
     The first housing may be formed with a slide-accommodating portion for at least partly accommodating the slide, such that the slide is movable along the connecting directions of the housings or in the forward and backward directions of the first housing. The slide-accommodating portion preferably has an operation opening to enable operation of the pushable portion. The pushable portion preferably is exposed to the outside without projecting out from an opening edge of the operation opening. Accordingly, external matter is not likely to contact the slide, and hence the slide and its neighboring parts are not likely to be damaged. 
     A displacement-operating portion may project from the locking piece for unlocking the locking piece, and may be formed so as not to project out from the outer surface of the other housing. Accordingly, external matter is not likely to contact the displacement-operating portion of the locking piece, and hence the locking piece and its neighboring parts are not likely to be deformed and damaged by an external force. 
     These and other objects, features and advantages of the present invention will become apparent upon reading of the following detailed description of preferred embodiments and accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded perspective view of a connector according to one embodiment of the invention. 
     FIG. 2 is a side view in section showing female and male housings before being connected. 
     FIG. 3 is a side view in section showing the female and male housings during a connecting operation. 
     FIG. 4 is a side view in section showing the female and male housings properly connected. 
     FIG. 5 is a side view in section showing the female and male housings during a separating operation. 
     FIG. 6 is an exploded perspective view of a prior art connector. 
     FIG. 7 is a side view in section showing female and male housings of the prior art connector before being connected. 
     FIG. 8 is a side view in section showing the female and male housings of the prior art connector during a connecting operation. 
     FIG. 9 is a side view in section showing the female and male housings of the prior art connector properly connected. 
     FIG. 10 is a side view in section showing the female and male housings of the prior art connector during a separating operation. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A connector according to the invention is identified generally by the numeral  20  in FIGS. 1 to  5 . The connector  20  is provided with a female housing  21  and a male housing  22 , which can be engaged at least partly with each other as shown in FIGS. 1 and 2. Sides of the female and male housings  21  and  22  that are to be connected are referred to as the fronts in the following description. 
     The female housing  21  is formed e.g. of a synthetic resin and has a substantially rectangular parallelepiped shape. Cavities  24  are arranged substantially side by side in the connector housing, and are configured for accommodating female terminal fittings  23 . A tab insertion opening  25  is open in the front surface of each cavity  24 . When the female and male housings  21  and  22  are connected, the leading ends of male terminal fittings  39  provided in the male housing  22  are inserted into the cavities  24  through the respective tab insertion openings  25 . Thus the male terminal fittings  39  are connected with the female terminal fittings  23 . 
     Guide walls  28  project respectively at the left and right edges of the upper surface of the female housing  21 , and a substantially rectangular frame  29  connects the rear ends of the guide walls  28 . A locking piece  31  is provided between the left and right guide walls  28 . The locking piece  31  is coupled to the upper surface of the female housing  21  via left and right legs  32 . The legs  32  extend up from a location near the front the female connector housing  21 , and then extend substantially horizontally or longitudinally backward. The locking piece  31  is vertically elastically displaceable by deforming the legs  32 . A rear end portion of the locking piece  31  serves as a displacement-operating portion  36  under which a finger can be placed to raise the locking piece  31 . Alternatively or additionally, a jig may be used to manipulate or operate the locking piece  31 . The displacement-operating portion  36  is formed so as not to project out from the frame portion  29  at the rear surface of the female housing  21 . 
     A pushing portion  33  projects upwardly from a location near the rear end of the locking piece  31  and is operative to push a slide  50 , as described below. An insertion hole  34  is formed between the left and right legs  32  of the locking piece  31 , and is configured to receive an interlocking portion  55  that projects from the male housing  22 . Further, a locking claw  35  projects from the lower surface of the locking piece  31  for engagement with an engagement portion  55 A of the interlocking portion  55 . The interlocking portion  55  and its engaging portion  55 A are described later. The lower surface of the locking claw  35  is formed by two surfaces that have different inclinations, namely, a front surface that serves as a more steeply inclined guide surface  35 A and a rear surface that serves as a more moderately inclined bottom surface  35 B. The rear end surface of the locking claw  35  preferably is a substantially vertical engaging surface  35 C, which contacts the interlocking portion  55  when the locking claw  35  and the engaging portion  55 A are engaged with each other. 
     The male housing  22  is formed e.g. of a synthetic resin, and has a substantially rectangular parallelepiped shape. More particularly, the male housing  22  is provided at its front surface with a receptacle  40  that extends into the front surface of the male housing  22 . The receptacle  40  is dimensioned to receive at least part of the female housing  21 . Cavities  41  are arranged substantially side by side in a rear part of the receptacle  40 . The male terminal fittings  39  are accommodated in the cavities  41 , such that the leading ends of the male terminal fittings  39  project into the receptacle  40 . 
     The interlocking portion  55  projects forward from the back surface of the receptacle  40 , and can be inserted through the insertion hole  34  of the locking piece  31 . The interlocking portion  55  is formed with an elongate lock hole  56  aligned substantially along forward and backward directions, and a front end of the interlocking portion  55  serves as the engaging portion  55 A for engaging the locking claw  35  of the locking piece  31 . 
     A partition wall  42  is provided in an upper portion of the receptacle  40 , and a slide-accommodating portion  43  is defined above the partition wall  42  for accommodating the slide  50 , as described later. A groove  44  is formed in a front part of the partition wall  42  and is dimensioned to receive at least part of the locking piece  31 . Guides  45  extend down from the left and right edges of the groove  44 , and guide grooves  46  are defined between the guides  45  and the left and right side walls of the receptacle  40 . The guide walls  28  of the female housing  21  can be inserted at least partly into the guide grooves  46 . 
     A hollow substantially rectangular spring mount portion  47  is provided in the middle of the back part of the slide-accommodating portion  43 , and a coil spring  51  or comparable biasing means is mountable in the spring mount portion  47  for biasing the slide  50  forward. 
     Grooves  48  extend in forward and backward directions at the left and right sides of the ceiling surface of the slide-accommodating portion  43 , and a pair of locking projections  52  on the slide  50  are at least partly fit in the grooves  48 . The front ends of the grooves  48  do not extend up to the front surface of the male housing  22 , and thereby form front stops  48 A. The locking projections  52  of the slide  50  contact the front stops  48 A so that the slide  50  is limited in its movement and does not come out of the slide-accommodating portion  43 . An operation opening  49  is formed in the upper wall of the slide-accommodating portion  43  and extends from the front end to a middle position of this upper wall. 
     The slide  50  is formed e.g. of a synthetic resin into the shape of a substantially flat plate, and has a pair of wedge-shaped locking projections  52  near the left and right front ends of the upper surface thereof. The wedge-shaped locking projections  52  can be fit into the grooves  48  to lock the slide  50  in the slide-accommodating portion  43 . The slide  50  can be slid in forward and backward directions inside the slide-accommodating portion  43 , and is constantly biased forward by the coil spring  51  at the back of the slide-accommodating portion  43 . An elongate pushable portion  53  extends transversely from the center of the upper surface of the slide  50 . The pushable portion  53  projects at least partly into the operation opening  49  of the male housing  22  when the housings  21  and  22  are connected. The slide  50  can be pushed backward against a biasing force of the coil spring  51  by placing a finger and/or an operating jig on the pushable portion  53 . The pushable portion  53  preferably is exposed to the outside without projecting out from an opening edge of the operation opening  49 . A front end surface  54  of the slide  50  is inclined so that the pushing portion  33  of the locking piece  31  can be slid easily down or toward the female connector housing  21 , as described later. 
     The female and male housings  21  and  22  are connected by initially fitting the left and right guide walls  28  of the female housing  21  into the respective guide grooves  46  of the receptacle  40  of the male housing  22 . After sufficient insertion, the leading end of the interlocking portion  55  passes through the insertion hole  34  near the base end of the locking piece  31 , and contacts the locking claw  35 . The locking claw  35  is guided onto the interlocking portion  55  by the guide surface  35 A, and the locking piece  31  is displaced elastically upward. As a result, the locking claw  35  moves onto the upper surface of the engaging portion  55 A of the interlocking portion  55  while the bottom surface  35 B of the locking claw  35  is held in contact with the upper surface  55 A if the interlocking portion  55 , as shown in FIG.  3 . At this time or in the deflected position, the pushing portion  33  contacts the front face  54  of the slide  50  at the upper surfaces of the housings  21 ,  22 . Accordingly, further insertion of the female housing  21  pushes the slide  50  backward against the biasing force of the coil spring  51 . 
     The locking claw  35  moves over the engaging portion  55 A of the interlocking portion  55  substantially as the female housing  21  reaches its proper position. At this point, the locking piece  31  is restored elastically to its natural state with no external force acting on the locking piece  31 . Additionally, the locking claw  35  enters the lock hole  56  to engage the engaging portion  55 A, as shown in FIG.  4 . The pushing portion  33  and the front surface  54  of the slide  50  disengage from each other as the locking piece  31  is restored elastically. As a result, the slide  50  is returned substantially to its front position by the elastic restoring force of the coil spring  51 . When the slide  50  is returned to its front position, the locking piece  31  is in a position where the upper surface of the pushing portion  33  is in contact with the lower surface of the slide  50 . Thus, the slide  50  restricts an elastic displacement of the locking piece  31  in a disengaging direction (upward) from the interlocking portion  55 , and the housings  21 ,  22  are locked in their properly connected state. 
     In this properly connected state, the pushable portion  53  of the slide  50  does not project out from the opening edge of the operation opening  49 , and the displacement operating portion  36  of the locking piece  31  does not project out from the rear end edge of the female housing  21 . 
     The housing connecting operation conceivably could be interrupted with the housings  21  and  22  connected only partly, as shown in FIG.  3 . In this situation, the coil spring  51  biases the slide  50 , such that the pushing portion  33  of the locking piece  31  pushes the female housing  21  out of the receptacle  40 . In this way, a partial connection is prevented. 
     The properly connected housings  21  and  22  can be separated by placing a finger on the pushable portion  53  of the slide  50  to push the slide  50  backward against the biasing force of the coil spring  51  (see FIG.  5 ). Another finger then is placed below the displacement-operating portion  36  of the locking piece  31  while the slide  50  is held in the above-described position. Thus, the locking piece  31  is displaced elastically upward to disengage the locking claw  35  from the engaging portion  55 A of the interlocking portion  55 . Then, the female housing  21  is pulled in this state to cause the locking claw  35  to move onto the upper surface of the engaging portion  55 A of the interlocking portion  55 . Further pulling will separate the female housing  21  from the male housing  22 . 
     If the housing separating operation is interrupted halfway while the housings  21  and  22  still are connected partly, as shown in FIG. 5, the coil spring  51  biases the slide  50  to push the pushing portion  33  of the locking piece  31  and to urge the female housing  21  out of the receptacle  40 . This prevents the housings  21 ,  22  from being left partly connected while they are being separated. 
     According to this embodiment, the slide  50  is accommodated in the slide-accommodating portion  43  for movement in forward and backward directions. Additionally, the pushable portion  53  does not project out from the opening edge of the operation opening  49 , and therefore, external matter is unlikely to contact the slide  50 . Accordingly, deformation and/or damage of the slide  50  and its neighboring parts by an external force can be prevented. 
     Further, since the displacement operating portion  36  of the locking piece  31  does not project out from the outer surface of the female housing  21 , external matter is unlikely to contact the displacement operating portion  36 , which can prevent the locking piece  31  from being deformed and/or damaged by an external force. 
     The present invention is not limited to the above embodiment. For example, the following embodiment also is embraced by the technical scope of the invention as defined in the claims. Besides this embodiment, various changes can be made without departing from the scope and spirit of the invention as defined in the claims. 
     Although the displacement operating operation  36  of the locking piece  31  does not project out from the outer surface of the female housing  21  in the foregoing embodiment, it may not be provided or it may project out from the outer surface of the housing if being provided according to the invention. 
     In the case that the displacement-operating portion of the locking piece is not provided, a guide surface is provided, for example, on the rear surface of the locking claw  35  or on the inner surface of the engaging portion  55 A of the interlocking portion  55 . The guide surface extends in a direction to deform the locking piece  31  elastically upward when the housings  21 ,  22  are pulled in separating directions. In this way, the housings  21 ,  22  may be made separable even without a locking piece disengaging operation.