Abstract:
A housings ( 20 ) has a lock arm ( 30 ) that engages a mating housing ( 10 ) when the housings ( 10, 20 ) are connected completely. A cover ( 40 ) is mounted slidably on the housing ( 20 ) and is pushed rearward as the housings ( 10, 20 ) are being connected. The cover ( 40 ) is biased forward by springs ( 45 ) that have front ends connected releasably to the cover ( 40 ). The springs ( 45 ) separate the housings ( 10, 20 ) if the connecting operation is stopped too soon. However the springs ( 45 ) are released from the cover ( 40 ) and expand to an unbiased state when the connection is complete.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The invention relates to a connector with a partial connection detecting function. 
   2. Description of the Related Art 
   U.S. Pat. No. 6,109,956 and U.S. Pat. No. 6,196,867 disclose a connector with a partial connection detecting function. These connectors have male and female housings that are connectable with one another. A compression coil spring is mounted in the female housing so that backward movement of the rear end of the spring is prevented. The male housing pushes the front end of the spring backward in the process of connecting the housings. As a result, the spring contracts resiliently and accumulates a biasing force. 
   The rear end of the spring is freed and moves back when the two housings are connected properly and locked together. Thus, the biasing force is released and the spring elongates backward. On the other hand, the accumulated biasing force of the spring separates the housings if the connecting operation is stopped before the two housings are connected properly, thereby providing an indication of an incomplete connection. 
   A receptacle of the male housing or a rib on the outer surface of the receptacle engages and presses the front end of the spring in the process of connecting the two housings. Thus, the above construction cannot be applied to male housings that have a short receptacle or receptacles that cannot have a rib because the biasing spring cannot be pressed. There has been a demand to use a spring to detect partial connection on such connectors. 
   The invention was developed in view of the above problem and an object is to improve overall operability of the connection and/or separation. 
   SUMMARY OF THE INVENTION 
   The invention relates to a connector with a housing that is connectable with a mating housing. A lock arm is provided on the housing and is resiliently engageable with a lock projection on the mating housing. A slider and at least one biasing means are provided in the housing. The slider is slidable substantially along forward and backward directions and the biasing means is extendible and compressible substantially along forward and backward directions. The biasing means has a rear end fixed to the housing and a front end that is locked temporarily at a position receded from the front of the slider. The temporarily locked state can be canceled by a resilient force acting when the biasing member is resiliently compressed to a specified extent or more. The front end of the slider contacts a pushing portion at a position on the mating housing behind the lock projection to push the front end in a connected state before the lock arm engages the lock projection. 
   The front end of the slider contacts the pushing portion of the housing before the lock arm engages the lock projection. The pushing portion pushes the slider as the connecting operation continues. The rear end of the biasing means is fixed to the housing and the front end is locked temporarily by the slider. Thus, the biasing means is compressed resiliently as the slider is pushed. During this time, the lock arm is engaged with the lock projection and passes the lock projection while being resiliently displaced. The lock arm returns to engage the lock projection when the two housings are connected properly. Thus, the two housings are locked in their properly connected state. The biasing means is compressed resiliently to at least a specified extent. Thus, the resilient force cancels the temporarily locked state and the biasing means is freed from the resiliently compressed state while the front end of the biasing means extends substantially towards the front end of the slider. 
   The resilient force of the compressed biasing means separates the housings if the connecting operation is stopped before the housings are connected properly. As a result, partial connection can be detected. 
   The front end of the slider is extended forward and the pushing portion for pushing the slider is behind the lock projection. Thus, the slider is pushed to compress the biasing means before the lock arm and the lock projection engage. Therefore, a partial connection detecting function using the biasing means is exhibited securely even in connectors have a short receptacle and cannot have a pushing rib on the outer surface of a housing. 
   The slider preferably includes a locking means for locking the front end of the biasing means that has returned to its free state. 
   The front end of the biasing means is locked by the locking means of the slider when the two housings are connected properly to return the biasing means to its free state. This prevents the biasing means from unnecessarily making loose movements. 
   The lock arm preferably is seesaw-shaped. The front end of the lock arm is engageable with the lock projection, while the rear end thereof is operable to disengage the front end of the lock arm from the lock projection. The rear end of the biasing means is fixed to the rear end of the lock arm. 
   The biasing means is deformed resiliently to accumulate the resilient force and curves when the slider is pushed with the lock arm that has been displaced pivotally by the engagement with the lock projection. The biasing means is mounted in a pivoting space for the lock arm. Thus, a mounting space for the biasing member spring is saved to enable a compact housing. 
   The slider preferably has an unlocking portion for pressing the rear end of the lock arm. Thus, the lock arm is displaced pivotally to free the lock projection from the locked state when the slider is moved back sufficiently for the two housings to be connected properly with each other. 
   The biasing means is compressed gradually and accumulates a biasing force when the slider is moved back sufficiently to connect the two housings properly. The unlocking portion presses the rear end of the lock arm to displace or rock the lock arm pivotally when the slider is moved back by the specified distance. Thus, the locked state of the lock projection is canceled and the biasing force of the biasing means separates the housings. 
   The pushing portion preferably is on part of a surface passing the center of the one housing and extending substantially along a connecting direction of the two housings so that the part intersects with a surface passing the lock projection. Thus, the outer shape of the one housing in a direction extending along the surface passing the lock projection can be smaller. 
   The slider preferably has an accommodating chamber in which a movable member is accommodated. The front end of the biasing means is mounted to the movable member. 
   Locking means preferably can lock the movable member temporarily to the slider in two spaced apart positions. 
   The biasing means preferably comprises two biasing elements arranged substantially symmetrically with respect to the slider. 
   These and other objects, features and advantages of the present invention will become more apparent upon reading of the following detailed description of preferred embodiments and accompanying drawings. It should be understood that even though embodiments are separately described, single features thereof may be combined to additional embodiments. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a front view of a male housing according to one embodiment of the invention. 
       FIG. 2  is a front view of a female housing having a slide cover mounted thereon. 
       FIG. 3  is a rear view of the female housing having the slide cover mounted thereon. 
       FIG. 4  is a side view of the female housing having the slide cover mounted thereon. 
       FIG. 5  is a plan view of the female housing having the slide cover mounted thereon. 
       FIG. 6  is a longitudinal section showing a state before a female terminal is inserted into the female housing. 
       FIG. 7  is a partial section showing a mounting portion for a biasing spring. 
       FIG. 8  is a plan view in section showing a state before the male and female housings are connected. 
       FIG. 9  is a longitudinal section showing the state before the male and female housings are connected. 
       FIG. 10  is a longitudinal section showing a state where the pushing of the slide cover is started. 
       FIG. 11  is a longitudinal section showing a final stage of a connecting operation. 
       FIG. 12  is a longitudinal section when locking is effected. 
       FIG. 13  is a longitudinal section when the male and female housings are locked in their properly connected state. 
       FIG. 14  is a longitudinal section showing a state where unlocking is effected. 
       FIG. 15  is a longitudinal section showing a state where the female housing is pulled backward. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   A connector according to the invention is illustrated in  FIGS. 1 to 15 . The connector has a male housing  10  and a female housing  20  that are connectable with each other along a connecting direction CD, as shown in  FIG. 9 . In the following description, ends of the housings  10 ,  20  to be connected with each other are referred to as the front. 
   The male housing  10  is made e.g. of a synthetic resin and has a receptacle  12  projecting integrally from a wall  11 A of an apparatus  11  installed in a vehicle or the like, as shown in  FIGS. 1 ,  8  and  9 . The receptacle  12  is a tube with a elliptic front view, and the back surface is recessed in the apparatus  11 . Thus, a projecting length of the receptacle  12  form the wall  11 A is short. Three tab-shaped male terminals  14  project substantially side by side along a transverse direction TD from the back surface of the receptacle  12 . 
   Two lock projections  15  project substantially symmetrically in the widthwise and longitudinal middle positions of the upper and lower surfaces of the receptacle  12 . A guiding surface  16  is formed at the front of each lock projection  15  and slopes towards the back. 
   A connection detecting rib  18  projects at a back side of the ceiling surface of the male housing  10  receded from a position near the left end when viewed from front. 
   The female housing  20  also is made e.g. of a synthetic resin and has a wide elliptic terminal accommodating portion  21 , as shown in  FIG. 2 . About the front two-thirds of the terminal accommodating portion  21  is fittable into the male housing  10  (see  FIG. 13 ). Three cavities  22  are formed in the terminal accommodating portion  21  and conform to the arrangement of the male terminals  14  in the male housing  10 . As shown in  FIG. 6 , a female terminal  24  is secured to an end of a wire  23  and is inserted into each cavity  22 . The female terminal  24  is locked first by a metal lock  25  and then is locked doubly by a side-type retainer  27 . The retainer  27  has a detection groove  28  that faces the rib  18  of the male housing  10  and engages the rib  18  when the retainer  27  is pushed to a proper position. 
   A lock arm  30  is provided in a substantially widthwise center of the upper surface of the terminal accommodating portion  21  for locking the male and female housings  10 ,  20  in their properly connected state. The lock arm  30  is narrow and long in forward and backward directions and has a length substantially equal to the length of the terminal-accommodating portion  21 . The front end of the lock arm  30  is near a mount position of the retainer  27  and the rear end of the lock arm  30  projects back from the rear surface of the terminal-accommodating portion  21 . A support  31  extends down from the lower surface of the lock arm  30  at a position slightly before the longitudinal middle of the lock arm  30 . The support  31  couples the lock arm  30  to the upper surface of the terminal-accommodating portion  21  at position about ⅓ of the entire length from the rear of the terminal-accommodating portion  21 . The lock arm  30  can be displaced pivotally about the support  31  in a seesaw-like manner. 
   A lock groove  32  is formed in the lower surface of the lock arm  30  and extends from the rear of the lock arm  30  to a position slightly receded from the front end of the lock arm  30 . A front surface  32 A of the lock groove  32  is engageable with the upper lock projection  15  of the male housing  10 . A slanted guiding surface  33  is formed before the lock groove  32 , and a wide operable plate  34  projects up at the rear end of the lock arm  30 , as shown in  FIG. 3 . 
   The front end of the lock arm  30  moves onto the lock projection  15  and causes the lock arm  30  to displace pivotally. The lock projection  15  fits into the lock groove  32  and engages the front surface  32 A to effect locking when the lock arm  30  passes the lock projection  15 . The lock arm  30  then returns towards its initial posture. The operable plate  34  can be pressed down towards the female housing  20  to lift the front side of the lock arm  30  in this state. Thus, the lock projection  15  exits from the lock groove  32  to effect unlocking. 
   A slide cover  40  is made e.g. of a synthetic resin and is mounted on the female housing  20 . The slide cover  40  is substantially a tube with a front plate  41 , as shown in  FIGS. 2 and 6 . Portions of the slide cover  40  rearward of the front plate  41  surround the bottom surface of the terminal-accommodating portion  21 , the opposite side surfaces of the front of the terminal-accommodating portion  21 , the opposite side surfaces of the lock arm  30  and the upper surface of the lock arm  30 . A guide groove  42  is formed in the inner bottom surface of the slide cover  40  and extends in forward and backward directions FBD. The slide cover  40  is mounted movably on the female housing  20  substantially along forward and backward directions FBD and substantially parallel to the connecting direction CD by slidably fitting a stopper  36  on the bottom surface of the terminal-accommodating portion  21  into the guide groove  42 . The front plate  41  of the slide cover  40  has a window  43  that permits entry of the receptacle  12  and the lock projections  15  of the male housing  10 , as shown in  FIG. 2 . 
   An accommodating chamber  46  is formed in an upper part in the slide cover  40  for accommodating two biasing springs  45  and the like. The biasing springs  45  may be compression coil springs, leaf springs, resilient (rubber) rods, or the like. 
   A wide movable member  48  is accommodated in the accommodating chamber  46  and extends over substantially the entire width of the accommodating chamber  46 . As shown in  FIG. 8 , guide grooves  50  are formed in opposite side surfaces of the accommodating chamber  46 . The guide grooves  50  have open rear ends and extend to positions slightly receded from the front edge. Slidable members  51  project from the opposite left and right side surfaces of the movable member  48  and fit slidably in the guide grooves  50  so that the movable member  48  is movable along forward and backward directions FBD in the accommodating chamber  46 . 
   Spring mounts  53  project at opposite widthwise ends of the movable member  48  and the operable plate  34  of the lock arm  30  substantially facing each other so that the front and rear spring mounts  53  are paired. The front end of each spring  45  is pressed onto the spring mount  53  of the movable member  48  and the rear end thereof mounted onto the spring mount  53  of the operable plate  34  to fix each spring  45 . 
   Resilient locks  55  project up from the opposite widthwise ends of the upper surface of the movable member  48  and then extend back. Locking sections  56  are formed at the leading ends of the respective resilient locks  55 . Each locking section  56  has a vertically aligned locking surface  56 A facing to the rear (left in  FIG. 7 ) and a slanted surface  56 B facing to the front (right in  FIG. 7 ). The locking sections  56  fit in first locking holes  57  formed in the ceiling of the slide cover  40  at positions slightly before the longitudinal center. 
   The springs  45  initially are mounted in a substantially unbiased state between the movable member  48  and the operable plate  34  of the lock arm  30 . Additionally, the locking sections  56  of the movable member  48  are fit in the first locking holes  57  of the slide cover  40  to hold the slide cover  40  temporarily at a position where backward movement is prevented. Simultaneously, the stopper  36  engages the rear end of the guide groove  42  to prevent forward movement of the slide cover  40 . The front plate  41  is substantially flush with the front surface of the terminal-accommodating portion  21  in this condition. 
   The springs  45  can be compressed while the locking sections  56  of the resilient locks  55  are in the first locking holes  57 . The compressed springs  45  create resilient restoring forces that cause the resilient locks  55  to curve inwardly. Thus, the slanted surfaces  56 B permit the locking sections  56  to exit the first locking holes  57 . 
   Second locking holes  58  are formed in the ceiling of the slide cover  40  forward of the first locking holes  57  and are configured to receive the locking sections  56  of the resilient locks  55 . The locking sections  56  may be released the first locking holes  57 . As a result, the resilient forces of the springs  56  will move the movable member  48  and the resilient locks  55  forward. The locking sections  56  then will fit into the second locking holes  58  when the springs  45  reach their unbiased state. At this time, the movable member  48  is in the window hole  43  of the front plate  41  of the slide cover  40 . 
   A force of a specified intensity or higher may pull the movable member  48  back while the locking sections  56  of the resilient locks  55  are fit in the second locking holes  58 . As a result, the springs  45  exert forces to deform the resilient locking pieces  55  inwardly. The slanted surfaces  56 B then permit the locking sections  56  to exit from the second locking holes  58 . 
   An unlocking portion  60  projects in the widthwise and longitudinal center of the ceiling of the slide cover  40  for pressing the operable plate  34  of the lock arm  30 . A cam surface  61  is defined at the rear (right in  FIG. 14 ) of the unlocking portion  60  and inclines forward toward the bottom end. The cam surface  61  contacts the upper end of the operable plate  34  when the slide cover  40  is moved back. Thus, the operable plate  34  is pressed down towards the female housing  20  and the lock arm  30  pivots to effect unlocking. 
   An escaping recess  49  is formed in the upper surface of the movable member  48  for permitting the passage of the unlocking portion  60 . 
   The female housing  20  initially is in a state where the locking sections  56  of the resilient locks  55  of the movable member  48  are fit in the first locking holes  57 . Additionally, the springs  45  are substantially in an unbiased or lightly compressed state between the movable member  48  and the operable plate  34  of the lock arm  30 . The slide cover  40  is at an advanced position where the front plate  41  is substantially flush with the front surface of the terminal-accommodating portion  21  of the female housing  20 , as shown in  FIG. 9 . 
   The female housing  20  then is connected in the connecting direction CD with the male housing  10 , as shown by an arrow in  FIG. 9 . As a result, the receptacle  12  and the lock projections  15  of the male housing  10  enter the slide cover  40  from the front. The front plate  41  of the slide cover  40  contacts the wall surface  11 A of the apparatus  11 , as shown in  FIG. 10 , before the upper lock projection  15  engages the front end of the lock arm  30 . 
   The slide cover  40  is pushed by the wall surface  11 A as the connection progresses. The movable member  48  is held releasably with the slide cover  40  and is moved back relative to the female housing  20  while resiliently compressing the springs  45 . The guiding surface  33  at the front end of the lock arm  30  contacts the guiding surface  16  of the upper lock projection  15  as the connection approaches its final stage: As a result, the front end of the lock arm  30  moves onto the lock projection  15  and the lock arm  30  pivots about the support  31 . At this time, the springs  45  are compressed further the longitudinal axes thereof curve (see e.g.  FIG. 11 ). 
   The front end of the lock arm  30  passes the upper lock projection  15  when the two housings  10 ,  20  are connected properly. Thus, the lock arm  30  is restored resiliently so that the lock groove  32  receives the upper lock projection  15 , as shown in  FIG. 12 . The front surface  32 A of the lock groove  32  then engages the upper lock projection  15  to lock the two housings  10 ,  20  in their properly connected state with the male and female terminals  14 ,  24  connected properly together. Simultaneously, the resilient forces of the springs  45  exceed the specified intensity. As a result, the resilient locks  55  curve sufficiently for the locking sections  56  to exit the first locking holes  57 , as shown in  FIG. 12 . The springs  45  then expand towards their unbiased state and move the movable member  48  forward. 
   The movable member  48  is in the window  43  when the springs  45  are returned to their unbiased state. Additionally, the locking sections  56  of the resilient locks  55  fit in the second locking holes  58  to hold the movable member  48 , as shown in  FIG. 13 . In this way, the connecting operation is completed. 
   The biasing springs  45  return to their unbiased state, and therefore are not set in fatigue. Additionally, the movable member  48  is immediately above the front end of the lock arm  30  to prevent inadvertent pivotal displacement of the lock arm  30  and to achieve a doubly locked state. Further, abnormal noise resulting from loose movements of the springs  45  and the movable member  48  in the accommodating chamber  46  can be prevented. 
   The connecting operation may be stopped approximately in the  FIG. 11  state and before the two housings  10 ,  20  are connected properly. In this event, the resilient forces of the compressed springs  45  push the operable plate  34  of the lock arm  30  and separate the female housing  20  from the male housing  10 . In this way, the partly connected condition of two housings  10 ,  20  is detected and the connecting operation may be carried out again. 
   The female housing  20  may have to be separated from the male housing  10  for maintenance or other reason. In this case, the slide cover  40  is pulled back from the state shown in  FIG. 13 . Reward movement of the slide cover  40  compresses the springs  45 , and urges the cam surface  61  of the unlocking portion  60  against the operable plate  34  of the lock arm  30 . Thus, the operable plate  34  is pressed down, as shown in  FIG. 14 , and the lock arm  30  pivots sufficiently to disengage the lock groove  32  from the upper lock projection  15  to effect unlocking. 
   The resilient forces of the resiliently compressed springs  45  then push the operable plate  34  of the lock arm  30 , and the female housing  20  is pulled back and separated from the male housing  10 . During this time, a force also acts to pull the movable member  48  back. As a result, the resilient locks  55  deform sufficiently for the locking sections  56  to exit the second locking holes  58  and the movable member  48  is pulled back, as shown in  FIG. 15 . 
   The female housing  20  is returned to the initial state, as shown in  FIG. 9 . Thus, the springs  45  are unbiased, the locking sections  56  of the resilient locks  55  of the movable member  48  are in the first locking holes  57  and the front plate  41  of the slide cover  40  is flush with the front surface of the terminal accommodating portion  21 . 
   As described above, the front end of the slide cover  40  is extended forward. Thus, the slide cover  40  can be pushed using the wall surface  11 A of the apparatus  11 , and the springs  45  can be compressed resiliently. Therefore, even if the receptacle  12  has a short length, the partial connection detecting function of the springs  45  is exhibited. 
   The rear ends of the springs  45  are fixed to the operable plate  34  of the lock arm  30 , and the springs  45  are mounted utilizing the pivoting space for the lock arm  30 . Thus, a mounting space for the springs  45  is saved to enable a compact female housing  20 . 
   The slide cover  40  is pulled back to separate the two housings  10 ,  20  for maintenance or other reason. Thus, the springs  45  compress gradually and accumulate resilient forces. Sufficient rearward movement of the slide cover  40  presses the unlocking portion  60  against the operable plate  34  of the lock arm  30  and pivots the lock arm  30  to effect unlocking. The female housing  20  then is urged back from the male housing  10  by the resilient forces of the springs  45 . In other words, the two housings  10 ,  20  can be separated easily by utilizing the biasing forces of the springs  45 . 
   The invention is not limited to the above described and illustrated embodiment. For example, the following embodiments are also embraced by the technical scope of the present invention as defined by the claims. Beside the following embodiments, various changes can be made without departing from the scope and spirit of the present invention as defined by the claims. 
   The invention is not limited to applications where a connector is coupled to an apparatus, and may be applied to wire-to-wire connectors. 
   The above-described pushing portion is behind the lock projections and pushes the slide cover, but need not always be formed on the entire surface extending normal to a connecting direction of the two housings like the wall surface of the apparatus in the foregoing embodiment. For example, the pushing portion may be formed only on a surface passing the lock projections out of surfaces extending in the center of the male housing along the connecting directions of the two housings. In such a case, a dimension of the outer shape of the male housing in a direction normal to the surface passing the lock projections can be made smaller. 
   Conversely, the pushing portion may be on a surface intersecting the surface passing the lock projections. In such a case, a dimension of the outer shape of the male housing in a direction along the surface passing the lock projections can be made smaller. 
   The lock projections may be on the female housing, whereas the lock arm, the springs and the slide cover may be in the male housing.