Patent Publication Number: US-11664625-B2

Title: Connector assembly

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is based on and claims priority under 35 U.S.C. § 119 to Japanese Patent Application No. JP2020-203588 filed Dec. 8, 2020, the contents of which are incorporated herein in their entirety by reference. 
     BACKGROUND OF THE INVENTION 
     This invention relates to a connector assembly comprising a first connector and a second connector with a mating detecting member. 
     Referring to FIGS. 60 to 63, JPB3060296 (Patent Document 1) discloses a connector assembly 900 of this type. The connector assembly 900 comprises a first connector 910 and a second connector 920. The first connector 910 comprises a first housing 912. The first housing 912 is provided with a first lock portion 913. The second connector 920 comprises a second housing 922 and a positioning assurance device 926, or a mating detecting member 926. The second housing 922 is mateable with the first housing 912 along an X-direction. The second housing 922 is provided with a second lock portion 923 and a traverse piece 924. The second lock portion 923 is positionable at any of a lock position, which is shown in FIG. 63, and a release position shown in FIG. 61. The second lock portion 923 has a stop wing 9232. When the second lock portion 923 is positioned at the lock position, the first lock portion 913 and the second lock portion 923 lock a mated state where the second housing 922 is mated with the first housing 912. The mating detecting member 926 is movable relative to the second housing 922 in the X-direction between an allowable position, which is shown in FIG. 60, and a regulating position shown in FIG. 63. The mating detecting member 926 has a stopping arm 9262 and a blocking tongue piece 9264. 
     Referring to FIG. 61, when the mating detecting member 926 is positioned at the allowable position, a movement of the second lock portion 923 from the lock position to the release position is allowed. When the mating detecting member 926 is positioned at the allowable position in a middle of a mating process of the second housing 922 with the first housing 912, the stopping arm 9262 of the mating detecting member 926 is positioned in a negative X-direction beyond the stop wing 9232 of the second lock portion 923 so that the mating detecting member 926 is immovable to the regulating position. Referring to FIG. 62, when the mating detecting member 926 is positioned at the allowable position under a state where the mating of the second housing 922 with the first housing 912 is completed, the stopping arm 9262 of the mating detecting member 926 is positioned in a positive Z-direction beyond the stop wing 9232 of the second lock portion 923 so that the mating detecting member 926 is movable to the regulating position. Referring to FIG. 63, when the mating detecting member 926 is positioned at the regulating position, the blocking tongue piece 9264 of the mating detecting member 926 is positioned in a negative Z-direction beyond the traverse piece 924 of the second housing 922 so that the movement of the second lock portion 923 from the lock position to the release position is regulated. 
     The connector assembly 900 of Patent Document 1 is configured so that an operator can continuously perform an operation of mating the first connector 910 with the second connector 920 and an operation of moving the mating detecting member 926 by applying force to the mating detecting member 926 when the first connector 910 and the second connector 920 are mated with each other. When an operator continuously performs the mating operation and the movement operation, the operator perceives, at about the same time, two clicking sensations: a clicking sensation produced by the completion of the mating of the first connector 910 with the second connector 920; and a clicking sensation produced by a movement of the mating detecting member 926 from the allowable position to the regulating position. Accordingly, if there occurs a fault that the mating detecting member 926 is erroneously moved from the allowable position to the regulating position under a state where the mating of the second connector 920 with the first connector 910 is not completed, an operator cannot recognize the incompletion of the mating of the second connector 920 with the first connector 910. 
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to provide a connector assembly which is configured so that an operation of mating a second connector with a first connector and an operation of moving a mating detecting member are independently performed and which enables an operator to reliably recognize an incompletion of the mating of the second connector with the first connector upon the incompletion due to some reason. 
     One aspect of the present invention provides a connector assembly comprising a first connector and a second connector. The first connector comprises a first housing. The first housing is provided with a first lock portion and a stopper. The second connector comprises a second housing, a mating detecting member and a shift mechanism. The second housing is mateable with the first housing along a front-rear direction. The first housing is positioned forward of the second housing in the front-rear direction. The second housing is provided with a second lock portion. The second lock portion is positionable at any of a lock position and a release position. When the second lock portion is positioned at the lock position, the first lock portion and the second lock portion lock a mated state where the second housing is mated with the first housing. The mating detecting member is movable relative to the second housing in the front-rear direction between a regulating position and an allowable position. The allowable position is positioned rearward of the regulating position in the front-rear direction. A movement of the second lock portion from the lock position to the release position is regulated when the mating detecting member is positioned at the regulating position. The movement of the second lock portion from the lock position to the release position is allowed when the mating detecting member is positioned at the allowable position. The mating detecting member has an abutment portion. The abutment portion is movable in a direction intersecting with the front-rear direction by an operation of the shift mechanism. When the second housing starts to be mated with the first housing, the abutment portion is positioned on an imaginary line which extends in the front-rear direction and passes through the stopper. When the second housing is mated with the first housing under a state where the mating detecting member is positioned at the regulating position, the abutment portion abuts against the stopper, and the mating detecting member is moved from the regulating position toward the allowable position. The mating detecting member is positioned at the allowable position when a mating of the second housing with the first housing is completed. When the shift mechanism is operated under a state where the mating detecting member is positioned at the allowable position, the abutment portion is moved to a position which is deviated from the imaginary line. The mating detecting member is moved from the allowable position to the regulating position when the mating detecting member is pushed forward in the front-rear direction under a state where the abutment portion is deviated from the imaginary line. 
     The connector assembly of the present invention is configured as follows: when the second housing is mated with the first housing under the state where the mating detecting member is positioned at the regulating position, the abutment portion abuts against the stopper, and the mating detecting member is moved from the regulating position toward the allowable position; and the mating detecting member is positioned at the allowable position when the mating of the second housing with the first housing is completed. Accordingly, the connector assembly of the present invention is configured so that the mating detecting member is always moved from the allowable position to the regulating position after the mating of the second housing with the first housing is completed. Specifically, an operation of mating the second connector with the first connector and an operation of moving the mating detecting member from the allowable position to the regulating position are independently performed in the connector assembly of the present invention. Thus, the connector assembly of the present invention enables an operator to reliably recognize an incompletion of the mating of the second connector with the first connector upon the incompletion due to some reason. 
     An appreciation of the objectives of the present invention and a more complete understanding of its structure may be had by studying the following description of the preferred embodiment and by referring to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a side view showing a connector assembly according to an embodiment of the present invention. In the figure, a first connector and a second connector are not mated with each other while a mating detecting member of the second connector is positioned at a regulating position. 
         FIG.  2    is a cross-sectional view showing the connector assembly of  FIG.  1   , taken along line A-A. 
         FIG.  3    is a top view showing the connector assembly of  FIG.  1   . 
         FIG.  4    is a cross-sectional view showing the connector assembly of  FIG.  3   , taken along line B-B. 
         FIG.  5    is a cross-sectional view showing the connector assembly of  FIG.  3   , taken along line C-C. 
         FIG.  6    is a cross-sectional view showing the connector assembly of  FIG.  3   , taken along line D-D. 
         FIG.  7    is another side view showing the connector assembly of  FIG.  1   . In the figure, the second connector is in a middle of a mating process of being mated with the first connector while the mating detecting member is positioned at the regulating position. 
         FIG.  8    is a cross-sectional view showing the connector assembly of  FIG.  7   , taken along line E-E. 
         FIG.  9    is a top view showing the connector assembly of  FIG.  7   . 
         FIG.  10    is a cross-sectional view showing the connector assembly of  FIG.  9   , taken along line F-F. 
         FIG.  11    is a cross-sectional view showing the connector assembly of  FIG.  9   , taken along line G-G. 
         FIG.  12    is a cross-sectional view showing the connector assembly of  FIG.  9   , taken along line H-H. In the figure, a part of the connector assembly is illustrated enlarged. 
         FIG.  13    is a cross-sectional view showing the connector assembly of  FIG.  9   , taken along line I-I. 
         FIG.  14    is still another side view showing the connector assembly of  FIG.  1   . In the figure, a first lock portion of the first connector and a second lock portion of the second connector lock a mated state where a second housing is mated with a first housing, while the mating detecting member is positioned at an allowable position. 
         FIG.  15    is a cross-sectional view showing the connector assembly of  FIG.  14   , taken along line J-J. 
         FIG.  16    is a top view showing the connector assembly of  FIG.  14   . 
         FIG.  17    is a cross-sectional view showing the connector assembly of  FIG.  16   , taken along line K-K. 
         FIG.  18    is a cross-sectional view showing the connector assembly of  FIG.  16   , taken along line L-L. 
         FIG.  19    is a cross-sectional view showing the connector assembly of  FIG.  16   , taken along line M-M. 
         FIG.  20    is a cross-sectional view showing the connector assembly of  FIG.  16   , taken along line N-N. 
         FIG.  21    is yet another side view showing the connector assembly of  FIG.  1   . In the figure, the first lock portion of the first connector and the second lock portion of the second connector lock the mated state of the second housing with the first housing while a shift operation portion of the mating detecting member is pushed down. 
         FIG.  22    is a cross-sectional view showing the connector assembly of  FIG.  21   , taken along line O-O. 
         FIG.  23    is a top view showing the connector assembly of  FIG.  21   . 
         FIG.  24    is a cross-sectional view showing the connector assembly of  FIG.  23   , taken along line P-P. 
         FIG.  25    is a cross-sectional view showing the connector assembly of  FIG.  23   , taken along line Q-Q. In the figure, a part of the connector assembly is illustrated enlarged. 
         FIG.  26    is a cross-sectional view showing the connector assembly of  FIG.  23   , taken along line R-R. In the figure, a part of the connector assembly is illustrated enlarged. 
         FIG.  27    is yet still another side view showing the connector assembly of  FIG.  1   . In the figure, the first lock portion of the first connector and the second lock portion of the second connector lock the mated state of the second housing with the first housing while the mating detecting member is positioned at the regulating position. 
         FIG.  28    is a cross-sectional view showing the connector assembly of  FIG.  27   , taken along line S-S. 
         FIG.  29    is a top view showing the connector assembly of  FIG.  27   . 
         FIG.  30    is a cross-sectional view showing the connector assembly of  FIG.  29   , taken along line T-T. 
         FIG.  31    is a cross-sectional view showing the connector assembly of  FIG.  29   , taken along line U-U. 
         FIG.  32    is a cross-sectional view showing the connector assembly of  FIG.  29   , taken along line V-V. In the figure, a part of the connector assembly is illustrated enlarged. 
         FIG.  33    is yet still another side view showing the connector assembly of  FIG.  1   . In the figure, the first lock portion of the first connector and the second lock portion of the second connector lock the mated state of the second housing with the first housing while the mating detecting member starts to be moved from the regulating position toward the allowable position. 
         FIG.  34    is a cross-sectional view showing the connector assembly of  FIG.  33   , taken along line W-W. 
         FIG.  35    is a top view showing the connector assembly of  FIG.  33   . 
         FIG.  36    is a cross-sectional view showing the connector assembly of  FIG.  35   , taken along line AA-AA. 
         FIG.  37    is a cross-sectional view showing the connector assembly of  FIG.  35   , taken along line AB-AB. In the figure, a part of the connector assembly is illustrated enlarged. 
         FIG.  38    is a cross-sectional view showing the connector assembly of  FIG.  35   , taken along line AC-AC. 
         FIG.  39    is a rear view showing the connector assembly of  FIG.  1   . In the figure, the mating detecting member is positioned at the allowable position while the second lock portion is positioned at a release position. 
         FIG.  40    is a cross-sectional view showing the connector assembly of  FIG.  39   , taken along line AD-AD. In the figure, a part of the connector assembly is illustrated enlarged. 
         FIG.  41    is another rear view showing the connector assembly of  FIG.  1   , wherein: the second lock portion is positioned between a lock position and the release position; the first lock portion and the second lock portion do not lock the mated state of the second housing with the first housing; and the mating detecting member is positioned between the allowable position and the regulating position. 
         FIG.  42    is a cross-sectional view showing the connector assembly of  FIG.  41   , taken along line AE-AE. 
         FIG.  43    is a cross-sectional view showing the connector assembly of  FIG.  41   , taken along line AF-AF. In the figure, a part of the connector assembly is illustrated enlarged. 
         FIG.  44    is a cross-sectional view showing the connector assembly of  FIG.  41   , taken along line AG-AG. 
         FIG.  45    is a perspective view showing the second connector which is included in the connector assembly of  FIG.  1   . In the figure, the mating detecting member is positioned at the allowable position. 
         FIG.  46    is a side view showing the second connector of  FIG.  45   . 
         FIG.  47    is another perspective view showing the second connector of  FIG.  45   . In the figure, the mating detecting member is positioned at the regulating position. 
         FIG.  48    is a side view showing the second connector of  FIG.  47   . 
         FIG.  49    is an exploded, perspective view showing the second connector of  FIG.  45   . 
         FIG.  50    is a perspective view showing the mating detecting member which is included in the second connector of  FIG.  49   . 
         FIG.  51    is a front view showing the mating detecting member of  FIG.  50   . 
         FIG.  52    is a bottom view showing the mating detecting member of  FIG.  50   . 
         FIG.  53    is a side view showing the mating detecting member of  FIG.  50   . 
         FIG.  54    is a top view showing a shroud cover which is included in the second connector of  FIG.  49   . 
         FIG.  55    is a rear, perspective view showing the shroud cover of  FIG.  54   . 
         FIG.  56    is a perspective view showing the first connector which is included in the connector assembly of  FIG.  1   . 
         FIG.  57    is a front view showing the first connector of  FIG.  56   . 
         FIG.  58    is a top view showing the first connector of  FIG.  56   . 
         FIG.  59    is a side view showing the first connector of  FIG.  56   . 
         FIG.  60    is a perspective view showing a connector assembly of Patent Document 1. 
         FIG.  61    is a cross-sectional view showing the connector assembly of  FIG.  60   . In the figure, a first lock portion and a second lock portion do not lock a mated state where a second housing is mated with a first housing. 
         FIG.  62    is another cross-sectional view showing the connector assembly of  FIG.  60   . In the figure, the first lock portion and the second lock portion lock the mated state of the second housing with the first housing while a mating detecting member is positioned at an allowable position. 
         FIG.  63    is still another cross-sectional view showing the connector assembly of  FIG.  60   . In the figure, the first lock portion and the second lock portion lock the mated state of the second housing with the first housing while the mating detecting member is positioned at a regulating position. 
     
    
    
     While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims. 
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     As shown in  FIG.  1   , a connector assembly  10  according to an embodiment of the present invention comprises a first connector  100  and a second connector  200 . The first connector  100  and the second connector  200  are mateable with each other along a front-rear direction. In the present embodiment, the front-rear direction is an X-direction. Specifically, it is assumed that forward is a positive X-direction while rearward is a negative X-direction. 
     As shown in  FIG.  57   , the first connector  100  of the present embodiment comprises a first housing  110  and first terminals  150 . 
     Referring to  FIG.  56   , the first housing  110  of the present embodiment is made of insulator. The first housing  110  is provided with a socket housing accommodating portion  111 , an upper surface  1112 , two first lock portions  112  and two stoppers  114 . 
     As shown in  FIG.  56   , the socket housing accommodating portion  111  of the present embodiment is a space which is opened at its rear end and extends in the front-rear direction. 
     As shown in  FIG.  56   , the upper surface  1112  of the present embodiment defines an upper end of the socket housing accommodating portion  111  in an up-down direction. The upper surface  1112  has a flat-plate shape perpendicular to the up-down direction. In the present embodiment, the up-down direction is a Z-direction. Specifically, upward is a positive Z-direction while downward is a negative Z-direction. 
     As shown in  FIG.  56   , each of the first lock portions  112  of the present embodiment is positioned around a middle of the first housing  110  in a right-left direction. In the present embodiment, the right-left direction is a Y-direction. Specifically, it is assumed that rightward is a positive Y-direction while leftward is a negative Y-direction. Each of the first lock portions  112  is provided on the upper surface  1112 . Each of the first lock portions  112  extends upward in the up-down direction from the upper surface  1112 . Each of the first lock portions  112  extends in the front-rear direction. 
     As shown in  FIGS.  56  and  58   , each of the first lock portions  112  has a first lock surface  1122 , an upper surface  1124  and an oblique surface  1126 . 
     As shown in  FIG.  56   , the first lock surface  1122  of the present embodiment defines a front end of the first lock portion  112  in the front-rear direction. The first lock surface  1122  is a plane perpendicular to the front-rear direction. 
     As shown in  FIG.  57   , the upper surface  1124  of the present embodiment defines an upper end of the first lock portion  112  in the up-down direction. The upper surface  1124  is a plane perpendicular to the up-down direction. 
     As shown in  FIG.  58   , the oblique surface  1126  of the present embodiment is positioned rearward of the upper surface  1124  in the front-rear direction. As shown in  FIG.  56   , the oblique surface  1126  is a plane oblique to the front-rear direction. The oblique surface  1126  extends forward and upward. 
     As shown in  FIG.  58   , each of the stoppers  114  of the present embodiment is provided on the upper surface  1112 . The stoppers  114  correspond to the first lock portions  112 , respectively, and each of the stoppers  114  is positioned outward in the right-left direction beyond the first lock portion  112  corresponding thereto. As shown in  FIG.  56   , each of the stoppers  114  extends upward in the up-down direction from the upper surface  1112 . Each of the stoppers  114  extends in the front-rear direction. 
     Referring to  FIG.  57   , each of the first terminals  150  of the present embodiment is made of metal. Each of the first terminals  150  is a so-called pin contact. 
     As shown in  FIG.  6   , the second connector  200  of the present embodiment comprises a second housing  300 , a mating detecting member  400 , a shift mechanism  500  and second terminals  250 . 
     Referring to  FIGS.  6  and  32   , the second housing  300  of the present embodiment is mateable along the front-rear direction with the first housing  110  which is positioned forward of the second housing  300  in the front-rear direction. As shown in  FIG.  49   , the second housing  300  consists of a shroud cover  302  and a socket housing  304 . 
     As shown in  FIGS.  49 ,  54  and  55   , the shroud cover  302  of the present embodiment has a first housing accommodating portion  3022 , a top plate  3023 , a preventing portion  3024 , guiding portions  330 , two protrusions  340 , two resilient portions  360  and two hole portions  370 . In other words, the second housing  300  is provided with the guiding portions  330 . 
     As shown in  FIG.  49   , the first housing accommodating portion  3022  of the present embodiment is a space which is opened at its front end and extends in the front-rear direction. 
     As shown in  FIG.  55   , the top plate  3023  of the present embodiment defines an upper end of the shroud cover  302 . The top plate  3023  has a flat-plate shape perpendicular to the up-down direction. 
     As shown in  FIG.  49   , the preventing portion  3024  of the present embodiment is positioned above the first housing accommodating portion  3022  in the up-down direction. The preventing portion  3024  is a part of the top plate  3023 . 
     As shown in  FIG.  55   , each of the guiding portions  330  of the present embodiment is a guide rail extending in the front-rear direction. Each of the guiding portions  330  is opened at a rear end of the shroud cover  302 . 
     As shown in  FIG.  54   , each of the protrusions  340  of the present embodiment protrudes outward in the right-left direction. The protrusions  340  correspond to the resilient portions  360 , respectively. Each of the protrusions  340  protrudes outward in the right-left direction from the resilient portion  360  corresponding thereto. Each of the protrusions  340  has a retaining portion  350  and a slope portion  355 . In other words, the second housing  300  has the retaining portions  350 . 
     As shown in  FIG.  54   , each of the retaining portions  350  of the present embodiment is positioned at a rear part of the shroud cover  302 . The retaining portion  350  defines a front end of the protrusion  340  in the front-rear direction. The retaining portion  350  is a plane perpendicular to the front-rear direction, 
     As shown in  FIG.  54   , the slope portion  355  of the present embodiment is positioned rearward of the retaining portion  350  in the front-rear direction. The slope portion  355  faces rearward in the front-rear direction and outward in the right-left direction. The slope portion  355  extends forward in the front-rear direction and outward in the right-left direction. 
     As shown in  FIG.  54   , each of the resilient portions  360  of the present embodiment extends forward from the rear end of the shroud cover  302 . Each of the resilient portions  360  is resiliently deformable. Specifically, each of the resilient portions  360  resiliently supports the protrusion  340  corresponding thereto. 
     As shown in  FIG.  54   , each of the hole portions  370  of the present embodiment is an elongated hole extending in the front-rear direction. The hole portions  370  correspond to the resilient portions  360 , respectively. Each of the hole portions  370  is positioned inward in the right-left direction beyond the resilient portion  360  corresponding thereto. 
     As described above, the resilient portion  360  is resiliently deformable and the hole portion  370  is positioned inward in the right-left direction beyond the resilient portion  360  corresponding thereto. Accordingly, the resilient portion  360  is resiliently deformable inwardly in the right-left direction so that the protrusion  340  is movable inward in the right-left direction. 
     As shown in  FIG.  6   , the socket housing  304  of the present embodiment is fixed to the shroud cover  302 . As shown in  FIG.  49   , the socket housing  304  is provided with a second lock portion  310 . In other words, the second housing  300  is provided with the second lock portion  310 . 
     As shown in  FIGS.  20  and  40   , the second lock portion  310  of the present embodiment is positionable at any of a lock position LP and a release position RP. The second lock portion  310  is movable in the up-down direction. However, the present invention is not limited thereto. A movement direction of the second lock portion  310  may be, for example, the right-left direction. Specifically, the second lock portion  310  should be movable in a perpendicular direction perpendicular to the front-rear direction. In other words, the movement direction of the second lock portion  310  should be the perpendicular direction. The second lock portion  310  is positioned at the lock position LP when in its initial state. Referring to  FIGS.  15  and  20   , when the second lock portion  310  is positioned at the lock position LP, the first lock portions  112  and the second lock portion  310  lock a mated state where the second housing  300  is mated with the first housing  110 . 
     As shown in  FIG.  49   , the second lock portion  310  has a locking lug  312 , a release operation portion  314  and a resilient supporting portion  317 . 
     As shown in  FIG.  49   , the locking lug  312  of the present embodiment is positioned at a front end of the second lock portion  310  in the front-rear direction. Referring to  FIGS.  20  and  40   , a position of the locking lug  312  upon the second lock portion  310  being at the lock position LP is positioned below a position of the locking lug  312  upon the second lock portion  310  being at the release position RP. 
     As shown in  FIG.  40   , the locking lug  312  has second lock surfaces  3122 , a lower surface  3124  and a front end  3126 . 
     As shown in  FIG.  40   , each of the second lock surfaces  3122  of the present embodiment is a surface facing rearward in the front-rear direction. The second lock surface  3122  defines a rear end of the locking lug  312  in the front-rear direction. 
     As shown in  FIG.  40   , the lower surface  3124  of the present embodiment is a surface facing downward in the up-down direction. The lower surface  3124  defines a lower end of the locking lug  312  in the up-down direction. 
     As shown in  FIG.  40   , the front end  3126  of the present embodiment is positioned at a front end of the locking lug  312  in the front-rear direction. The front end  3126  is also the front end of the second lock portion  310 . 
     As shown in  FIG.  49   , the release operation portion  314  of the present embodiment defines a rear end of the second lock portion  310 . Referring to  FIGS.  20  and  40   , when the release operation portion  314  is pushed down, the locking lug  312  is moved upward in the up-down direction perpendicular to the front-rear direction so that the second lock portion  310  is moved to the release position RP. More specifically, when the release operation portion  314  is pushed down, the locking lug  312  is moved upward in the up-down direction perpendicular to the front-rear direction so that the second lock portion  310  is moved from the lock position LP to the release position RP. 
     As shown in  FIG.  49   , the resilient supporting portion  317  of the present embodiment extends in the front-rear direction. The resilient supporting portion  317  is positioned rearward of the locking lug  312  in the front-rear direction. The resilient supporting portion  317  is positioned forward of the release operation portion  314  in the front-rear direction. The resilient supporting portion  317  is resiliently deformable. 
     As shown in  FIG.  2   , the second lock portion  310  of the present embodiment is provided with two movement regulating projections  316 . 
     As shown in  FIG.  2   , each of the movement regulating projections  316  of the present embodiment protrudes outward in the right-left direction. The movement regulating projections  316  are positioned at opposite ends, respectively, of the second lock portion  310  in the right-left direction. Each of the movement regulating projections  316  is positioned around the front end of the second lock portion  310  in the front-rear direction. Each of the movement regulating projections  316  is positioned rearward of the locking lug  312  in the front-rear direction. As shown in  FIG.  49   , the movement regulating projections  316  protrude outward in the right-left direction from outward ends, respectively, of the resilient supporting portion  317  in the right-left direction. Each of the movement regulating projections  316  is positioned forward of the release operation portion  314  in the front-rear direction. When the release operation portion  314  is pushed downward, each of the movement regulating projections  316  is moved upward in the up-down direction perpendicular to the front-rear direction. 
     As shown in  FIG.  43   , each of the movement regulating projections  316  has an oblique surface  3162 , an upper surface  3163  and a rear surface  3168 . 
     As shown in  FIG.  43   , the oblique surface  3162  of the present embodiment is a plane intersecting with the front-rear direction. The oblique surface  3162  extends forward in the front-rear direction and downward in the up-down direction. The oblique surface  3162  faces forward and upward. 
     As shown in  FIG.  43   , the upper surface  3163  of the present embodiment defines an upper end of the movement regulating projection  316  in the up-down direction. The upper surface  3163  is a plane intersecting with the up-down direction. The upper surface  3163  faces upward in the up-down direction. 
     As shown in  FIG.  43   , the rear surface  3168  of the present embodiment defines a rear end of the movement regulating projection  316  in the front-rear direction. The rear surface  3168  is a plane intersecting with the front-rear direction. The rear surface  3168  faces rearward in the front-rear direction. 
     As shown in  FIG.  6   , the second lock portion  310  of the present embodiment has a fulcrum portion  318 . 
     As shown in  FIG.  13   , the fulcrum portion  318  is positioned around a middle of the second lock portion  310  in the front-rear direction. Referring to  FIGS.  13  and  40   , the second lock portion  310  is movable in a seesaw manner with the fulcrum portion  318  acting as a fulcrum. As shown in  FIG.  49   , the locking lug  312  is positioned forward of the fulcrum portion  318  in the front-rear direction. The release operation portion  314  is positioned rearward of the fulcrum portion  318  in the front-rear direction. Each of the movement regulating projections  316  is positioned between the fulcrum portion  318  and the locking lug  312 . Each of the movement regulating projections  316  is nearer to the locking lug  312  than to the fulcrum portion  318 . 
     Referring to  FIG.  49   , the mating detecting member  400  of the present embodiment is made of resin. Referring to  FIG.  2   , the mating detecting member  400  is attached to the shroud cover  302 . Referring to  FIGS.  1  and  14   , the mating detecting member  400  of the present embodiment is movable relative to the second housing  300  in the front-rear direction between a regulating position RGP and an allowable position ALP. The allowable position ALP is positioned rearward of the regulating position RGP in the front-rear direction. 
     As shown in  FIG.  50   , the mating detecting member  400  has two arm portions  405  and two projecting portions  410 . 
     As shown in  FIG.  49   , each of the arm portions  405  of the present embodiment extends forward in the front-rear direction. Each of the arm portions  405  has an upper surface  406 . The upper surface  406  faces upward in the up-down direction. 
     As shown in  FIG.  50   , the projecting portions  410  of the present embodiment correspond to the arm portions  405 , respectively. Each of the projecting portions  410  is positioned at a front end of the arm portion  405  corresponding thereto. Each of the projecting portions  410  protrudes downward from the front end of the arm portion  405  corresponding thereto. 
     As shown in  FIGS.  50  and  52   , each of the projecting portions  410  has an abutment portion  412 , a first lower surface  413 , a front slope portion  416 , a rear slope portion  418  and a second lower surface  419 . In other words, the mating detecting member  400  has the abutment portions  412 . 
     As shown in  FIG.  50   , the abutment portion  412  of the present embodiment faces forward in the front-rear direction. The abutment portion  412  defines a front end of the projecting portion  410  in the front-rear direction. In other words, the abutment portion  412  defines a front end of the mating detecting member  400 . The abutment portion  412  is a plane perpendicular to the front-rear direction. 
     As shown in  FIG.  50   , the first lower surface  413  of the present embodiment faces downward in the up-down direction. The first lower surface  413  defines a lower end of the projecting portion  410  in the up-down direction. The first lower surface  413  is a plane perpendicular to the up-down direction. 
     As shown in  FIG.  53   , the front slope portion  416  of the present embodiment is positioned rearward of the abutment portion  412  in the front-rear direction. The front slope portion  416  is positioned below the abutment portion  412  in the up-down direction. The front slope portion  416  is positioned forward of the first lower surface  413  in the front-rear direction. The front slope portion  416  is positioned above the first lower surface  413  in the up-down direction. The front slope portion  416  faces forward and downward. The front slope portion  416  extends forward and upward. 
     As shown in  FIG.  53   , the rear slope portion  418  of the present embodiment is positioned rearward of the abutment portion  412  in the front-rear direction. The rear slope portion  418  is positioned below the abutment portion  412  in the up-down direction. The rear slope portion  418  is positioned rearward of the first lower surface  413  in the front-rear direction. The rear slope portion  418  is positioned above the first lower surface  413  in the up-down direction. The rear slope portion  418  faces rearward and downward. The rear slope portion  418  extends rearward and upward. 
     As shown in  FIG.  52   , the second lower surface  419  of the present embodiment is positioned at the front end of the mating detecting member  400 . The second lower surface  419  is positioned inward of the first lower surface  413  in the right-left direction. As shown in  FIG.  50   , the second lower surface  419  faces downward in the up-down direction. The second lower surface  419  is a plane perpendicular to the up-down direction. The second lower surface  419  is positioned above the first lower surface  413  in the up-down direction. 
     As shown in  FIGS.  49  and  52   , the mating detecting member  400  has a regulating portion  420 , click protrusions  430  and retained portions  460 . 
     As shown in  FIG.  49   , the regulating portion  420  of the present embodiment is positioned around a rear end of the mating detecting member  400  in the front-rear direction. The regulating portion  420  is positioned rearward of any of the arm portions  405  in the front-rear direction. The regulating portion  420  has a substantially plate-like shape. 
     As shown in  FIG.  6   , when the mating detecting member  400  is positioned at the regulating position RGP, the regulating portion  420  is positioned below the release operation portion  314  in the up-down direction to regulate the pushing down of the release operation portion  314 . Specifically, a movement of the second lock portion  310  from the lock position LP to the release position RP shown in  FIG.  40    is regulated when the mating detecting member  400  is positioned at the regulating position RGP. 
     As shown in  FIG.  40   , when the mating detecting member  400  is positioned at the allowable position ALP, the regulating portion  420  is positioned rearward in the front-rear direction beyond the release operation portion  314  so that the pushing down of the release operation portion  314  is allowed. Specifically, a movement of the second lock portion  310  from the lock position LP, which is shown in  FIG.  6   , to the release position RP is allowed when the mating detecting member  400  is positioned at the allowable position ALP. 
     As shown in  FIG.  52   , the click protrusions  430  of the present embodiment are positioned rearward of the retained portions  460 , respectively, in the front-rear direction. Each of the click protrusions  430  has a front slope portion  432  and a rear slope portion  434 . 
     As shown in  FIG.  52   , the front slope portion  432  of the present embodiment faces forward in the front-rear direction and inward in the right-left direction. The front slope portion  432  extends forward in the front-rear direction and outward in the right-left direction. The front slope portion  432  of each of the click protrusions  430  is positioned rearward of the retained portion  460  corresponding thereto in the front-rear direction. 
     As shown in  FIG.  52   , the rear slope portion  434  of the present embodiment faces rearward in the front-rear direction and inward in the right-left direction. The rear slope portion  434  extends rearward in the front-rear direction and outward in the right-left direction. The rear slope portion  434  is positioned rearward of the front slope portion  432  in the front-rear direction. 
     As shown in  FIG.  52   , each of the retained portions  460  of the present embodiment is positioned around a middle of the mating detecting member  400  in the front-rear direction. As shown in  FIG.  50   , the retained portions  460  are positioned below the arm portions  405 , respectively, in the up-down direction. Referring to  FIGS.  49  and  50   , each of the retained portions  460  is positioned below the regulating portion  420  in the up-down direction. As shown in  FIG.  52   , each of the retained portions  460  is positioned forward of the click protrusion  430  corresponding thereto in the front-rear direction. The retained portions  460  correspond to projecting portions  410 , respectively. Each of the retained portions  460  is positioned inward of the first lower surface  413  of the projecting portion  410  corresponding thereto in the right-left direction. Each of the retained portions  460  faces rearward in the front-rear direction. Each of the retained portions  460  is a plane perpendicular to the front-rear direction, 
     As shown in  FIG.  19   , the retaining portions  350  correspond to the retained portions  460 , respectively, and the retaining portion  350  and the retained portion  460  corresponding thereto prevent a rearward movement of the mating detecting member  400  in the front-rear direction relative to the second housing  300  beyond the allowable position ALP. 
     As shown in  FIG.  53   , the mating detecting member  400  is provided with guided portions  440  and a shift operation portion  450 . 
     As shown in  FIG.  50   , each of the guided portions  440  is an elongated protrusion extending in the front-rear direction. Referring to  FIGS.  10  and  17   , the guided portions  440  correspond to the guiding portions  330 , respectively, and the guiding portion  330  and the guided portion  440  corresponding thereto guide a movement of the mating detecting member  400  between the regulating position RGP and the allowable position ALP. The guided portion  440  and the guiding portion  330  corresponding thereto have sizes in the up-down direction which are large enough for the guided portion  440  to be smoothly guided by the guiding portion  330  corresponding thereto. 
     Referring to  FIG.  10   , when the mating detecting member  400  is positioned at the regulating position RGP, almost the whole of the guided portion  440  is accommodated in the guiding portion  330  corresponding thereto. In other words, when the mating detecting member  400  is positioned at the regulating position RGP, the guiding portion  330  and the guided portion  440  corresponding thereto have overlapping parts each extending long in the front-rear direction. Referring to  FIG.  17   , when the mating detecting member  400  is positioned at the allowable position ALP, a greater part of the guided portion  440  is not accommodated in the guiding portion  330  corresponding thereto and is positioned rearward beyond the guiding portion  330  corresponding thereto to be exposed to the outside of the second connector  200 . In other words, when the mating detecting member  400  is positioned at the allowable position ALP, the guiding portion  330  and the guided portion  440  corresponding thereto have overlapping parts each extending short in the front-rear direction. 
     As described above, the second connector  200  of the present embodiment is configured so that each of the guiding portions  330  is the guide rail extending in the front-rear direction while each of the guided portions  440  is the elongated protrusion extending in the front-rear direction. However, the present invention is not limited thereto. Specifically, the second connector  200  should be configured so that one of the guiding portion  330  and the guided portion  440  is an elongated protrusion extending in the front-rear direction while a remaining one of the guiding portion  330  and the guided portion  440  is a guide rail which extends in the front-rear direction and guides the elongated protrusion. 
     As shown in  FIG.  53   , the shift operation portion  450  is positioned at the rear end of the mating detecting member  400  in the front-rear direction. When the shift operation portion  450  is operated in the up-down direction, each of the abutment portions  412  is moved in the up-down direction perpendicular to the front-rear direction. However, the present invention is not limited thereto. The second connector  200  may be configured so that the abutment portion  412  is moved in a direction intersecting with the front-rear direction when the shift operation portion  450  is operated in the perpendicular direction perpendicular to the front-rear direction. 
     As described above, the guiding portion  330  and the guided portion  440  corresponding thereto have the overlapping parts each extending long in the front-rear direction when the mating detecting member  400  is positioned at the regulating position RGP. Accordingly, when the mating detecting member  400  is positioned at the regulating position RGP, a rear end of the guided portion  440  is almost immovable in the up-down direction relative to the guiding portion  330  corresponding thereto, and thereby the operation of the shift operation portion  450  in the up-down direction perpendicular to the front-rear direction is regulated. However, the present invention is not limited thereto. Specifically, the second connector  200  may be configured so that the operation of the shift operation portion  450  in the perpendicular direction perpendicular to the front-rear direction is regulated when the mating detecting member  400  is positioned at the regulating position RGP. 
     As described above, when the mating detecting member  400  is positioned at the allowable position ALP, the guiding portion  330  and the guided portion  440  corresponding thereto have the overlapping parts each extending short in the front-rear direction. Accordingly, when the mating detecting member  400  is positioned at the allowable position ALP, the rear end of the guided portion  440  is movable, to a great extent, in the up-down direction relative to the guiding portion  330  corresponding thereto, and thereby the shift operation portion  450  is operable in the up-down direction perpendicular to the front-rear direction. However, the present invention is not limited thereto. Specifically, the second connector  200  may be configured so that the shift operation portion  450  is operable in the perpendicular direction when the mating detecting member  400  is positioned at the allowable position ALP. Specifically, provided that the abutment portion  412  is movable in the direction intersecting with the front-rear direction, the shift operation portion  450  may be operable, for example, in the right-left direction when the mating detecting member  400  is positioned at the allowable position ALP. 
     As described above, the second connector  200  is configured so that the guided portion  440  and the guiding portion  330  corresponding thereto have the sizes in the up-down direction which are large enough for the guided portion  440  to be smoothly guided by the guiding portion  330  corresponding thereto. By this configuration, when the mating detecting member  400  is positioned at the regulating position RGP, the pushing down of the shift operation portion  450  only gives a slight shake to the shift operation portion  450  and hardly moves the shift operation portion  450 . Also, by this configuration, when the mating detecting member  400  is positioned at the allowable position ALP, the shift operation portion  450  is movable over a large distance upon the pushing down of the shift operation portion  450 . 
     Referring to  FIG.  10   , the shift mechanism  500  consists of the guiding portions  330 , the guided portions  440  and the shift operation portion  450 . In other words, the guiding portions  330 , the guided portions  440  and the shift operation portion  450  form the shift mechanism  500 . Referring to  FIGS.  18 ,  25  and  26   , each of the abutment portions  412  is movable in the direction intersecting with the front-rear direction by an operation of the shift mechanism  500 . More specifically, each of the abutment portions  412  is moved upward by the shift operation portion  450  of the shift mechanism  500  being pushed down. 
     As shown in  FIG.  52   , the mating detecting member  400  is formed with oblique surfaces  414 . The oblique surfaces  414  correspond to the projecting portions  410 , the guided portions  440 , and the click protrusions  430 , respectively. 
     As shown in  FIG.  52   , each of the oblique surfaces  414  of the present embodiment is positioned rearward of the abutment portion  412  of the projecting portion  410  corresponding thereto in the front-rear direction. Each of the oblique surfaces  414  is positioned inward of the guided portion  440  corresponding thereto in the right-left direction. Each of the oblique surfaces  414  is positioned inward of the first lower surface  413  of the projecting portion  410  corresponding thereto in the right-left direction. Each of the oblique surfaces  414  is positioned at a position same as a position of the click protrusion  430  corresponding thereto in the right-left direction. Each of the oblique surfaces  414  is positioned rearward of the second lower surface  419  of the projecting portion  410  corresponding thereto in the front-rear direction. As shown in  FIG.  12   , each of the oblique surfaces  414  faces rearward and downward. Each of the oblique surfaces  414  extends rearward and upward. Each of the oblique surfaces  414  is a plane oblique to the front-rear direction. 
     Referring to  FIG.  6   , each of the second terminals  250  of the present embodiment is made of metal and is a so-called socket contact. The second terminals  250  are held by the socket housing  304 . Referring to  FIG.  20   , the second terminals  250  are connected with the first terminals  150 , respectively, when the first connector  100  and the second connector  200  are mated with each other. 
     [Mating Operation] 
     A further description will be made below about a usual operation of mating the first connector  100  with the second connector  200  and behaviors of components of the connector assembly  10  upon the usual mating operation. 
     First, referring to  FIG.  2   , the second connector  200 , whose mating detecting member  400  is positioned at the regulating position RGP, is arranged rearward of the first connector  100  in the front-rear direction. Meanwhile, the abutment portions  412  of the second connector  200  are positioned rearward of the stoppers  114 , respectively, of the first connector  100  in the front-rear direction, and each of the abutment portions  412  faces the stopper  114  corresponding thereto in the front-rear direction. In other words, when the second housing  300  starts to be mated with the first housing  110 , the abutment portion  412  is positioned on an imaginary line IL which extends in the front-rear direction and passes through the stopper  114  corresponding thereto. 
     Next, the second housing  300  is moved forward relative to the first housing  110  so as to approach the first housing  110  in the front-rear direction in this state. Then, the first housing accommodating portion  3022  of the second connector  200  accommodates a part of the first housing  110  of the first connector  100  while the socket housing accommodating portion  111  of the first housing  110  of the first connector  100  accommodates a part of the socket housing  304  of the second connector  200 . Specifically, the connector assembly  10  changes its state into a mating start state shown in each of  FIGS.  7  to  13   . 
     Under the mating start state, none of the second terminals  250  of the second connector  200  are connected with the first terminals  150  of the first connector  100 . Under the mating start state, each of the abutment portions  412  is positioned rearward of the stopper  114  corresponding thereto in the front-rear direction and is brought into abutment with the stopper  114  corresponding thereto in the front-rear direction. Under the mating start state, the click protrusions  430  of the mating detecting member  400  are positioned forward in the front-rear direction beyond the retaining portions  350 , respectively, of the shroud cover  302 . Under the mating start state, the front end  3126  of the locking lug  312  of the second lock portion  310  is not in contact with any of the first lock portions  112  in the front-rear direction. In other words, the front end  3126  of the locking lug  312  of the second lock portion  310  is spaced rearwardly away from any of the first lock portions  112  in the front-rear direction under the mating start state. Specifically, the second lock portion  310  is positioned away from any of the first lock portions  112  in the front-rear direction when the mating detecting member  400  is positioned at the regulating position RGP while the abutment portion  412  abuts against the stopper  114  corresponding thereto. 
     Under the mating start state, the second housing  300  is moved forward relative to the first housing  110  so as to further approach the first housing  110 . Then, the mating detecting member  400  is moved rearward of the second housing  300  in the front-rear direction while the front end  3126  of the locking lug  312  of the second lock portion  310  of the second connector  200  is brought into contact with the oblique surfaces  1126  (see  FIG.  56   ) of the first lock portions  112  of the first connector  100  in the front-rear direction. Meanwhile, the regulating portion  420  of the mating detecting member  400  is positioned below the release operation portion  314  of the second lock portion  310 , and thereby the pushing down of the release operation portion  314  is still regulated. 
     In this state, the second housing  300  is moved forward relative to the first housing  110  so as to still further approach the first housing  110 . Then, the mating detecting member  400  is moved further rearward relative to the second housing  300  in the front-rear direction, and the front end  3126  of the locking lug  312  is lifted upward so that the resilient supporting portion  317  of the second lock portion  310  is resiliently deformed. Meanwhile, the oblique surfaces  414  of the projecting portions  410  of the mating detecting member  400  abut against the oblique surfaces  3162  of the movement regulating projections  316 , respectively, of the second lock portion  310  in the front-rear direction so that each of the projecting portions  410  is lifted upward. 
     The second housing  300  is moved forward relative to the first housing  110  so as to yet further approach the first housing  110  under the aforementioned state where the resilient supporting portion  317  of the second lock portion  310  is resiliently deformed. Then, the lower surface  3124  of the locking lug  312  rides over the upper surfaces  1124  (see  FIG.  56   ) of the first lock portions  112 , and the second lower surface  419  of each of the projecting portions  410  of the mating detecting member  400  rides over the upper surface  3163  of the movement regulating projection  316  corresponding thereto of the second lock portion  310 . In this state, the second housing  300  is moved forward relative to the first housing  110  so as to yet still further approach the first housing  110 . Then, the locking lug  312  rides over the first lock portions  112  to be moved forward beyond the first lock portions  112 , and each of the projecting portions  410  of the mating detecting member  400  rides over the movement regulating projection  316  corresponding thereto of the second lock portion  310  to be moved rearward beyond the movement regulating projection  316  corresponding thereto. Accordingly, the connector assembly  10  changes its state into a mating completion state shown in each of  FIGS.  14  to  20   , and the mating detecting member  400  reaches the allowable position ALP. Specifically, the mating detecting member  400  is positioned at the allowable position ALP when the mating of the second housing  300  with the first housing  110  is completed. In other words, the mating detecting member  400  is positioned at the allowable position ALP when the mating of the second connector  200  with the first connector  100  is completed. 
     The above operations and behaviors are summarized as follow: when the second housing  300  is mated with the first housing  110  under a state where the mating detecting member  400  is positioned at the regulating position RGP, the abutment portion  412  abuts against the stopper  114 , and the mating detecting member  400  is moved from the regulating position RGP toward the allowable position ALP; and, when the mating detecting member  400  is moved from the regulating position RGP to the allowable position ALP, the oblique surface  414  abuts against the movement regulating projection  316 , and the abutment portion  412  is moved upward in the up-down direction, and then the abutment portion  412  rides over the movement regulating projection  316  to be moved rearward in the front-rear direction beyond the movement regulating projection  316 . 
     The second lock portion  310  is positioned at the lock position LP under the aforementioned mating completion state. Under the mating completion state, each of the click protrusions  430  of the mating detecting member  400  is positioned rearward in the front-rear direction beyond the retaining portion  350  corresponding thereto of the shroud cover  302 . Under the mating completion state, the second lock surfaces  3122  of the locking lug  312  are positioned forward of the first lock surfaces  1122  of the first lock portions  112 , respectively, in the front-rear direction, and each of the second lock surfaces  3122  faces the first lock surface  1122  corresponding thereto in the front-rear direction. In other words, under the mating completion state, the first lock portions  112  and the second lock portion  310  lock the mated state where the second housing  300  is mated with the first housing  110 . 
     Under the mating completion state, the abutment portion  412  of each of the projecting portions  410  of the mating detecting member  400  is positioned rearward of the rear surface  3168  of the movement regulating projection  316  corresponding thereto in the front-rear direction and faces the rear surface  3168  thereof in the front-rear direction. Under the mating completion state, each of the retaining portions  350  is positioned rearward in the front-rear direction beyond the retained portion  460  corresponding thereto. Under the mating completion state, the second terminals  250  of the second connector  200  are connected with the first terminals  150 , respectively, of the first connector  100 . As described above, the mating detecting member  400  is positioned at the allowable position ALP under the mating completion state. Thus, under the mating completion state, the regulating portion  420  is positioned rearward in the front-rear direction beyond the release operation portion  314  so that the pushing down of the release operation portion  314  is allowed. Under the mating completion state, each of the abutment portions  412  is still positioned rearward of the stopper  114  corresponding thereto in the front-rear direction and still abuts against the stopper  114  corresponding thereto in the front-rear direction. 
     As described above, the connector assembly  10  in the mating completion state is configured as follows: the mating detecting member  400  is positioned at the allowable position ALP; the second lock portion  310  is positioned at the lock position LP; and the abutment portion  412  of each of the projecting portions  410  of the mating detecting member  400  is positioned rearward in the front-rear direction beyond the rear surface  3168  of the movement regulating projection  316  corresponding thereto and faces the rear surface  3168  thereof in the front-rear direction. Thus, even if the mating detecting member  400  is intended to be moved forward relative to the second housing  300  under the mating completion state, each of the abutment portions  412  abuts against the rear surface  3168  of the movement regulating projection  316  corresponding thereto from behind, and thereby the mating detecting member  400  is prevented from being moved forward relative to the second housing  300 . In other words, when the mating detecting member  400  is positioned at the allowable position ALP while the second lock portion  310  is positioned at the lock position LP, the movement regulating projection  316  is positioned forward in the front-rear direction beyond the abutment portion  412  corresponding thereto to regulate a movement of the mating detecting member  400  to the regulating position RGP. 
     In a first process where the connector assembly  10  changes its state from the mating start state to the mating completion state, the rear slope portion  434  (see  FIG.  52   ) of the click protrusion  430  of the mating detecting member  400  is brought into contact with the retaining portion  350  corresponding thereto of the shroud cover  302 . Upon the contact of the rear slope portion  434  with the retaining portion  350 , the resilient portion  360  (see  FIG.  54   ) is resiliently deformed inward in the right-left direction, and thereby the protrusion  340  is moved inward in the right-left direction. Thus, the click protrusion  430  can be moved rearward beyond the retaining portion  350  corresponding thereto in the first process. 
     When the shift operation portion  450  of the mating detecting member  400  is pushed down under the aforementioned mating completion state, the abutment portion  412  is moved upward in the up-down direction to be positioned above the movement regulating projection  316  corresponding thereto, and thereby the connector assembly  10  changes its state into a regulation release state shown in each of  FIGS.  21  to  26   . Specifically, when the shift mechanism  500  is operated under a state where the mating detecting member  400  is positioned at the allowable position ALP, the abutment portion  412  is moved to a position which is deviated from the imaginary line IL. 
     Under the regulation release state, the abutment portion  412  is positioned above the rear surface  3168  of the movement regulating projection  316  corresponding thereto in the up-down direction and does not face the rear surface  3168  thereof in the front-rear direction. Accordingly, the abutment portion  412  does not abut against the movement regulating projection  316  corresponding thereto when the mating detecting member  400  is moved forward relative to the second housing  300  under the regulation release state. In other words, the movement regulating projections  316  do not prevent a forward movement of the mating detecting member  400  relative to the second housing  300  under the regulation release state. Specifically, the regulation of the mating detecting member  400  by the movement regulating projections  316  is released when the abutment portions  412  are moved by the operation of the shift mechanism  500  under a state where the mating of the second housing  300  with the first housing  110  is completed while the second lock portion  310  is positioned at the lock position LP. Additionally, both of the abutment portion  412  and the front slope portion  416  of each of the projecting portions  410  are brought into contact with a rear slope portion  1148  of the stopper  114  corresponding thereto in the front-rear direction under the regulation release state. 
     Under the regulation release state, forward force is applied to the mating detecting member  400 . Then, the second lower surface  419  of the projecting portion  410  passes above the upper surface  3163  of the movement regulating projection  316  corresponding thereto while the first lower surface  413  of the projecting portion  410  rides over the upper surface  1144  of the stopper  114  corresponding thereto. 
     When the forward force is further applied to the mating detecting member  400  in this state, the oblique surface  414  of the projecting portion  410  is moved forward beyond the oblique surface  3162  of the movement regulating projection  316  corresponding thereto while the projecting portion  410  rides over the stopper  114  corresponding thereto to be moved forward beyond the stopper  114  corresponding thereto. Accordingly, the connector assembly  10  changes its state into a mating detecting state shown in each of  FIGS.  27  to  32   , and the mating detecting member  400  reaches the regulating position RGP. In other words, the mating detecting member  400  is moved from the allowable position ALP to the regulating position RGP when the mating detecting member  400  is pushed forward in the front-rear direction under a state where the abutment portion  412  is deviated from the imaginary line IL. 
     Under the mating detecting state, each of the click protrusions  430  of the mating detecting member  400  is positioned forward in the front-rear direction beyond the retaining portion  350  corresponding thereto of the shroud cover  302 . Under the mating detecting state, each of the abutment portions  412  is positioned forward in the front-rear direction beyond the stopper  114  corresponding thereto and does not face the stopper  114  corresponding thereto in the front-rear direction. Under the mating detecting state, the regulating portion  420  is positioned below the release operation portion  314  of the second lock portion  310  to regulate the pushing down of the release operation portion  314 . 
     In a second process where the connector assembly  10  changes its state from the mating completion state to the mating detecting state, the front slope portion  432  (see  FIG.  52   ) of the click protrusion  430  of the mating detecting member  400  is brought into contact with the slope portion  355  (see  FIG.  54   ) of the shroud cover  302  to provide a clicking sensation to an operator of the mating detecting member  400 . Accordingly, in the second process, the clicking sensation enables the operator of the mating detecting member  400  to clearly perceive that the mating detecting member  400  is being moved from the allowable position ALP to the regulating position RGP. Behaviors of the resilient portion  360  (see  FIG.  54   ) and the protrusion  340  upon the contact of the front slope portion  432  of the click protrusion  430  with the slope portion  355  of the shroud cover  302  in the second process are similar to the behaviors of the resilient portion  360  and the protrusion  340  upon the contact of the rear slope portion  434  of the click protrusion  430  with the retaining portion  350  in the first process as described above. Specifically, when the front slope portion  432  of the click protrusion  430  is brought into contact with the slope portion  355  of the shroud cover  302  in the second process, the resilient portion  360  is resiliently deformed inward in the right-left direction, and thereby the protrusion  340  is moved inward in the right-left direction. Thus, the click protrusion  430  can be moved forward beyond the retaining portion  350  corresponding thereto in the second process. 
     In the second process, a part of the upper surface  406  of the arm portion  405  of the mating detecting member  400  abuts against the preventing portion  3024  of the shroud cover  302  from below in the up-down direction. Thus, the arm portion  405  is prevented from being excessively moved upward in the second process. 
     The description is made above about the usual mating operation of the first connector  100  with the second connector  200 , which is arranged rearward of the first connector  100  and whose mating detecting member  400  is positioned at the regulating position RGP, and the behaviors of the components of the connector assembly  10  upon the usual mating operation. Alternatively, the connector assembly  10  might be operated in an unusual manner where the second connector  200  begins to be mated with the first connector  100  after the second connector  200 , whose mating detecting member  400  is not returned to the regulating position RGP and is still positioned at the allowable position ALP, is arranged rearward of the first connector  100 . The unusual mating operation and behaviors of the components of the connector assembly  10  upon the unusual mating operation are similar to the usual mating operation and their behaviors upon the usual mating operation except that the mating detecting member  400  is not moved relative to the second housing  300  in a process where the connector assembly  10  changes its state from a mating start state to a mating completion state. However, in the aforementioned unusual mating operation where the second connector  200 , whose mating detecting member  400  is positioned at the allowable position ALP, is mated with the first connector  100 , there might occur a special situation that the mating detecting member  400  is erroneously moved relative to the second housing  300  from the allowable position ALP toward the regulating position RGP in a state before the connector assembly  10  reaches the mating completion state, namely, in a mating incompletion state where the mating of the second housing  300  with the first housing  110  is not completed. A further description will be made later about behaviors of the components of the connector assembly  10  in the special situation. 
     In a case where the mating detecting member  400 , which is positioned at the regulating position RGP, and the second housing  300  are intended to be simultaneously pushed forward into the first housing  110  under the mating start state, each of the abutment portions  412  of the mating detecting member  400  is in abutment against the stopper  114  corresponding thereto of the first housing  110  from behind as described above. Accordingly, in this case, the mating of the second housing  300  with the first housing  110  is not completed, and thereby the connector assembly  10  never changes its state into the mating completion state. In other words, the connector assembly  10  of the present embodiment is prevented from changing its state into the mating completion state while the mating detecting member  400  maintains its location at the regulating position RGP. 
     [Behaviors of the Components of the Connector Assembly in the Special Situation] 
     As described above, in the usual mating operation, the second housing  300  begins to be mated with the first housing  110  after the second connector  200 , whose mating detecting member  400  is positioned at the regulating position RGP, is arranged rearward of the first connector  100 . Accordingly, in the usual mating operation, the connector assembly  10  takes a usual state where the mating detecting member  400  is positioned at the regulating position RGP under the mating incompletion state where the mating of the second connector  200  with the first connector  100  is not completed. Alternatively, the unusual mating operation, which is dissimilar to the usual mating operation, might be done as described above. In such an unusual mating operation where the second housing  300  starts to be mated with the first housing  110  after the second connector  200 , whose mating detecting member  400  is not returned to the regulating position RGP and is still positioned at the allowable position ALP, is arranged rearward of the first connector  100 , the connector assembly  10  takes an unusual state where the mating detecting member  400  is still positioned at the allowable position ALP even under the mating incompletion state where the mating of the second connector  200  with the first connector  100  is not completed. A further description will be made below about behaviors of the components of the connector assembly  10  in the special situation where the mating detecting member  400  is moved from the allowable position ALP toward the regulating position RGP in the unusual state which is different from the usual state. 
     First, in the unusual state, the mating detecting member  400  is moved forward while the shift operation portion  450  is pushed down. Then, the connector assembly  10  changes its state into a movement regulating state shown in each of  FIGS.  41  to  44   . Under the movement regulating state, each of the movement regulating projections  316  is positioned forward in the front-rear direction beyond the abutment portion  412  corresponding thereto while the rear surface  3168  of each of the movement regulating projections  316  is in contact with the abutment portion  412  corresponding thereto in the front-rear direction. Under the movement regulating state, the mating detecting member  400  is still positioned at the allowable position ALP while the second lock portion  310  is positioned at the release position RP. Specifically, a movement of the mating detecting member  400  from the allowable position ALP to the regulating position RGP is regulated under the movement regulating state. 
     In other words, when the mating detecting member  400  is positioned at the allowable position ALP even while the second lock portion  310  is positioned at the release position RP, each of the movement regulating projections  316  is positioned forward in the front-rear direction beyond the abutment portion  412  corresponding thereto to regulate the movement of the mating detecting member  400  to the regulating position RGP. 
     Next, the mating detecting member  400  is further moved forward under the movement regulating state. Then, the movement regulating projections  316  are pushed forward by the mating detecting member  400 , and thereby the second lock portion  310  is moved forward relative to the first connector  100  together with the mating detecting member  400 . 
     After that, the mating detecting member  400  is still further moved forward. Then, the second lock surface  3122  reaches a position same as a position of the first lock surface  1122  corresponding thereto in the front-rear direction. At this time, the resilient supporting portion  317  restores its original shape, and thereby the locking lug  312  of the second lock portion  310  is moved downward. Specifically, the second lock portion  310  is moved to the lock position LP (see  FIG.  20   ) at this time. Accordingly, each of the second lock surfaces  3122  of the locking lug  312  is positioned forward in the front-rear direction beyond the first lock surface  1122  of the first lock portion  112  corresponding thereto and faces the first lock surface  1122  thereof in the front-rear direction. In other words, the mating of the second housing  300  with the first housing  110  is completed. 
     The above operations and behaviors are summarized as follow: when the mating detecting member  400  is moved forward in the front-rear direction under the mating incompletion state where the mating of the second housing  300  with the first housing  110  is not completed, the movement regulating projections  316  are pushed by the mating detecting member  400  until the mating of the second housing  300  with the first housing  110  is completed. 
     After the completion of the mating of the second housing  300  with the first housing  110 , the connector assembly  10  can change its state into the mating detecting state by an operation similar to the usual mating operation as described above. Specifically, the operation as follows: after the completion of the mating of the second housing  300  with the first housing  110 , the mating detecting member  400  is moved forward while the shift operation portion  450  is pushed down. By the operation, the mating detecting member  400  can reach the regulating position RGP, and thereby the connector assembly  10  can change its state into the mating detecting state. 
     Since the connector assembly  10  of the present embodiment is configured as described above, the connector assembly  10  of the present embodiment has an advantage as follows: even if the mating detecting member  400  is erroneously moved from the allowable position ALP toward the regulating position RGP under the mating incompletion state where the mating of the second housing  300  with the first housing  110  is not completed, the mating of the second housing  300  with the first housing  110  is always completed before the mating detecting member  400  reaches the regulating position RGP. 
     [Release Operation to Release the Mating] 
     A further description will be made below about an operation of releasing the mating of the first connector  100  with the second connector  200 . 
     First, rearward force is applied to the mating detecting member  400  under the aforementioned mating detecting state. Then, the connector assembly  10  changes its state into a release start state shown in each of  FIGS.  33  to  38   . Under the release start state, the rear slope portion  418  of the projecting portion  410  is in contact with a front slope portion  1146  of the stopper  114  corresponding thereto in the front-rear direction. Under the release start state, the oblique surface  414  of the projecting portion  410  is still positioned forward beyond the oblique surface  3162  of the movement regulating projection  316  corresponding thereto. 
     Next, the rearward force is further applied to the mating detecting member  400  under the release start state. Then, the abutment portion  412  rides over the stopper  114  corresponding thereto to be moved rearward beyond the stopper  114  corresponding thereto, while the abutment portion  412  of the projecting portion  410  passes above the movement regulating projection  316  corresponding thereto to be moved rearward beyond the movement regulating projection  316  corresponding thereto. Thus, the mating detecting member  400  reaches the allowable position ALP. In other words, the connector assembly  10  changes its state into the mating completion state shown in each of  FIGS.  14  to  20   . 
     In a third process where the connector assembly  10  changes its state from the release start state to the mating completion state, a part of the upper surface  406  of the arm portion  405  of the mating detecting member  400  abuts against the preventing portion  3024  of the shroud cover  302  from below in the up-down direction. Thus, the arm portion  405  is prevented from being excessively moved upward in the third process. 
     Under the mating completion state, the second connector  200  is moved rearward relative to the first connector  100  while the second lock portion  310  is moved to the release position RP (see  FIG.  40   ) by the pushing down of the release operation portion  314  of the second lock portion  310 . Then, the mating of the first connector  100  with the second connector  200  is released 
     Although the specific explanation about the present invention is made above referring to the embodiments, the present invention is not limited thereto and is susceptible to various modifications and alternative forms. 
     The connector assembly  10  of the present embodiment is configured so that, when the mating detecting member  400  is positioned at the regulating position RGP, the movement of the second lock portion  310  from the lock position LP to the release position RP is regulated by the regulating portion  420  being positioned below the release operation portion  314  in the up-down direction to regulate the pushing down of the release operation portion  314 . However, the present invention is not limited thereto. Specifically, the connector assembly  10  may be modified so that, when the mating detecting member  400  is positioned at the regulating position RGP, the movement of the second lock portion  310  from the lock position LP to the release position RP is regulated by the regulating portion  420  being positioned above the locking lug  312  to regulate the upward movement of the locking lug  312 . 
     The second connector  200  of the present embodiment is configured so that the position of the locking lug  312  upon the second lock portion  310  being at the lock position LP is positioned below the position of the locking lug  312  upon the second lock portion  310  being at the release position RP. However, the present invention is not limited thereto. Specifically, the second connector  200  may be modified so that the position of the locking lug  312  upon the second lock portion  310  being at the lock position LP is positioned above the position of the locking lug  312  upon the second lock portion  310  being at the release position RP. 
     Although the connector assembly  10  of the present embodiment changes its state into the regulation release state by each of the abutment portions  412  being moved upward to be positioned above the movement regulating projections  316  corresponding thereto, the present invention is not limited thereto. Specifically, a movement direction of the abutment portion  412  is not limited, provided that the regulation of the mating detecting member  400  by the movement regulating projections  316  is released by the movement of the abutment portion  412  in the movement direction intersecting with the front-rear direction. 
     Although the second connector  200  of the present embodiment is configured so that the click protrusions  430  and the retained portions  460  are provided on the mating detecting member  400  while the retaining portions  350  are provided on the shroud cover  302 , the present invention is not limited thereto. Specifically, the reverse configuration is also possible. In other words, the second connector  200  may be modified so that the click protrusion  430  and the retained portion  460  are provided on the shroud cover  302  while the retaining portion  350  is provided on the mating detecting member  400 . 
     While there has been described what is believed to be the preferred embodiment of the invention, those skilled in the art will recognize that other and further modifications may be made thereto without departing from the spirit of the invention, and it is intended to claim all such embodiments that fall within the true scope of the invention.