Abstract:
A connector includes a female connector housing, that has a male terminal, and a male connector housing that has a female terminal for electrical connecting to the male terminal, and that is adapted to be fitted into the female connector. The male connector housing includes an inner housing which has the female terminal, and which is adapted to be fitted in the female connector housing so that the female terminal is connected to the male terminal, and an outer housing which is adapted to support the inner housing so that the inner housing is movable in a first direction in which the inner housing is fitted in the female connector housing and in a second direction perpendicular to the first direction. When the inner housing is fitted into the female connector housing, the inner housing is disposed so as to separate from the outer housing in the second direction with a first gap.

Description:
BACKGROUND OF THE INVENTION 
   This invention relates to a connector for electrically connecting female and male terminals together, and more particularly to a connector in which wear of contact portions of the female and male terminals due to vibration is reduced. 
   A connector, used, for example, in the wiring of a vehicle such as an automobile, undergoes vibration developing during the travel of the vehicle, and contact portions of female and male terminals are worn by such vibration, and in some cases the electrical connection becomes defective. Therefore, there is known a conventional connector in which relative motion between female and male connector housings, fitted together, is suppressed so as to reduce wear of contact portions of female and male terminals which rub against each other (see, for example, JP-A-2002-198127 (Pages 3 to 4, FIGS. 4 and 6)). 
   As shown in  FIGS. 5A and 5B , the connector  100 , disclosed in JP-A-2002-198127, comprises the female connector housing  102  holding the male terminals  103 , and the male connector housing  104  receiving the female terminals  101  for electrical connection to the respective male terminals  103 . The male connector housing  104  includes an inner housing  106  which holds the female terminals  101 , and is fitted into a hood portion  105  of the female connector housing  102 , and an outer housing  107  of a generally square tubular shape formed around the inner housing  106 . The male connector housing  104  is formed into an integral construction. 
   Limitation projections  108  are formed on an inner surface of the hood portion  15  of the female connector housing  102 , and these limitation projections  108  contact an outer surface of the inner housing  106  of the male connector housing  104  inserted and fitted in the hood portion  105 . As a result, relative motion of the female and male connector housings  102  and  104  in a direction perpendicular to the direction of fitting of these connector housings to each other is suppressed. 
   A lock arm  109  is formed on the outer housing  107  of the male connector housing  104 , and this lock arm  109  is retainingly engaged with an engagement projection of the female connector housing  102 . As a result, the rearward movement of the male connector housing  104  in the fitting direction is prevented, so that the fitted condition of the female and male connector housings  102  and  104  is maintained. 
   To reduce a load applied to the female and male terminals is effective in reducing wear of the contact portions of the female and male terminals due to vibration. However, in the connector  100  disclosed in JP-A-2002-198127, the inner housing  106  of the male connector housing  104 , holding the female terminals  101 , is formed integrally with the outer housing  107 . Therefore, when vibration is applied to the connector  100 , so that relative motion between the mutually-fitted female and male connector housings occurs, the overall weight of the male connector housing  104  is applied as a load directly to the female and male terminals  101  and  103 . 
   And besides, the limitation projections  108  in the connector  100 , disclosed in JP-A-2002-198127, suppress the relative motion in the direction perpendicular to the fitting direction, but is less effective in suppressing the relative motion in the fitting direction. As a result of this fact, along with the fact that the overall weight of the male connector housing  104  is applied as a load, there is a fear that wear of the female and male terminals  101  and  103  due to vibration is not sufficiently reduced. 
   Furthermore, when the limitation projections  108  in the connector  100 , disclosed in JP-A-2002-198127, are used for a long period of time, there is a fear that these limitation projections  108  are worn by relative motion of the female and male connector housings  102  and  104  in the fitting direction, and there is also a fear that relative motion of the female and male connector housings  102  and  104  in the direction perpendicular to the fitting direction also occurs. 
   SUMMARY OF THE INVENTION 
   This invention has been made in view of the above problems, and an object of the invention is to provide a connector in which a load, applied to female and male terminals, can be reduced, and also relative motion of mutually-fitted female and male connector housings both in a fitting direction and in a direction perpendicular to the fitting direction can be suppressed, thereby reducing wear of contact portions of the female and male terminals. 
   The above object has been achieved by a connector of the present invention having features recited in the following Paragraphs (1) to (4). 
   (1) A connector, comprising: 
   a female connector housing, that has a male terminal; and 
   a male connector housing that has a female terminal for electrical connecting to the male terminal, and that is adapted to be fitted into the female connector, 
   wherein the male connector housing includes:
         an inner housing which has the female terminal, and which is adapted to be fitted in the female connector housing so that the female terminal is connected to the male terminal; and   an outer housing which is adapted to support the inner housing so that the inner housing is movable in a first direction in which the inner housing is fitted in the female connector housing and in a second direction perpendicular to the first direction; and       

   wherein when the inner housing is fitted into the female connector housing, the inner housing is disposed so as to separate from the outer housing in the second direction with a first gap. 
   Preferably, when the inner housing is not fitted into the female connector housing, the inner housing contacts with the outer housing in the second direction or is separated from the outer housing with a second gap in the second direction. A width of the first gap is greater than that of the second gap. 
   (2) Preferably, a rib and a rib receiving portion are respectively formed on an outer surface of the inner housing and an inner surface of the outer housing which are opposed to each other in the second direction. When the inner housing is not fitted into the female connector housing, the rib contacts the rib reception portion, or is separated from the rib reception portion with the second gap. When the inner housing is fitted into the female connector housing, the rib is shifted away from the rib reception portion in the first direction so that the first gap is formed between the inner housing and the outer housing. 
   (3) Preferably, a first slanting surface is formed on the outer surface of the inner housing. A second slanting surface is formed on an inner surface of the female connector housing, and is corresponded to the first slanting surface. The first slanting surface is mated with the second slanting surface. 
   (4) Preferably, the connector further includes an urging unit that is interposed between the inner housing and the outer housing. When the inner housing is fitted into the female connector housing, the urging unit urges the inner housing in the first direction so that the first slanting surface of the inner housing is pressed against the second slanting surface of the female connector housing. 
   In the connector of the construction of the above Paragraph (1), the inner housing is supported by the outer housing in such a manner that the inner housing can move both in the first direction and in the second direction perpendicular to the first direction. Namely, the male connector housing is divided into the inner housing and the outer housing. 
   When the inner housing is not fitted into the female connector housing, the inner housing contacts the outer housing in the second direction perpendicular to the first direction, or is disposed in such a manner that the second gap is formed between the inner housing and the outer housing in the second direction perpendicular to the first direction. Therefore, during the operation for fitting the inner housing into the female connector housing, relative motion of the inner housing in the second direction is suppressed, and the inner housing can be smoothly fitted into the female connector housing. 
   When the inner housing is fitted in the female connector housing, the inner housing is disposed in such a manner that the first gap, being greater than the second gap, is formed between the inner housing and the outer housing in the second direction. Therefore, even when vibration acts on the connector, so that relative motion of the female and male connector housings occurs, the outer housing is prevented from interfering with the inner housing, and the load of the outer housing will not act on the female and male terminals. Therefore, the load, acting on the female and male terminals, is reduced, so that the load, acting on contact portions of these terminals, can be reduced. 
   In the connector of the construction of the above Paragraph (2), during the operation for fitting the inner housing into the female connector housing, the inner housing is moved in the first direction, and by doing so, the rib of the inner housing is displaced in the fitting direction, and is completely brought out of registry with the corresponding rib reception portion of the outer housing. As a result, a gap, corresponding to a height of the rib reception portion, is formed between the rib and the inner surface of the outer housing, and also a gap, corresponding to a height of the rib, is formed between the rib reception portion and the outer surface of the inner housing. With this simple construction, when the inner housing is not fitted in the female connector housing, the inner housing contacts the outer housing in the second direction, or is disposed in such a manner that the second gap is formed between the inner housing and the outer housing in the direction perpendicular to the fitting direction. Also, when the inner housing is fitted in the female connector housing, the inner housing is disposed in such a manner that the first gap, larger than the second gap, is formed between the inner housing and the outer housing in the second direction perpendicular to the first direction. 
   In the connector of the construction of the above Paragraph (3), the first slanting surface is formed on the outer surface of the inner housing, and the second slanting surface is formed on the inner surface of the female connector housing, and the first slanting surface is mated with the second slanting surface. These slanting surfaces intersect the first direction, and therefore relative motion of the inner housing and the female connector housing (which are fitted together) both in the fitting direction and in the second direction perpendicular to the fitting direction can be suppressed. Furthermore, when the mating slanting surfaces are worn, the inner housing is inserted deeper into the female connector housing, so that the first slanting surface is kept mated respectively with the second slanting surface, and therefore the relative motion can be suppressed for a long period of time. 
   In the connector of the construction of the above Paragraph (4), the urging unit, interposed between the inner housing and the outer housing, urges the inner housing in the first direction in such a manner that the slanting surface of the inner housing is pressed against the slanting surface of the female connector housing. With this construction, the slanting surface of the inner housing is always positively kept mated with the slanting surface of the female connector housing, and therefore relative motion of the inner housing and the female connector housing (which are fitted together) both in the first direction and in the second direction perpendicular to the first direction can be positively suppressed. A member, having spring properties, can suitably be used as the urging unit, and one example is a coil spring. 
   In the connector of the present invention, a load, applied to the female and male terminals, can be reduced, and also relative motion of the mutually-fitted female and male connector housings both in the first direction and in the second direction perpendicular to the first direction can be suppressed, thereby reducing wear of the contact portions of the female and male terminals. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above objects and advantages of the present invention will become more apparent by describing in detail preferred exemplary embodiments thereof with reference to the accompanying drawings, wherein: 
       FIG. 1  is an exploded, perspective view of one preferred embodiment of a connector of the present invention; 
       FIG. 2  is a perspective view showing an inner housing and an outer housing of a male connector housing, with the outer housing shown as being partly broken; 
       FIG. 3A  is a cross-sectional view of the male connector housing which is not fitted in a female connector housing, and  FIG. 3B  is an enlarged view of a portion surrounded by a broken line IIIb of  FIG. 3A ; 
       FIG. 4A  is a cross-sectional view of the male connector housing fitted in the female connector housing, and  FIG. 4B  is an enlarged view of a portion surrounded by a broken line IVb of  FIG. 4A ; and 
       FIGS. 5A and 5B  are cross-sectional views of a related connector. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   One preferred embodiment of a connector of the present invention will now be described in detail with reference to the drawings. 
     FIG. 1  is an exploded, perspective view of the connector of this embodiment,  FIG. 2  is a perspective view showing an inner housing and an outer housing of a male connector housing, with the outer housing shown as been partly broken,  FIG. 3A  is a cross-sectional view of the male connector housing which is not fitted in a female connector housing,  FIG. 3B  is an enlarged view of a portion surrounded by a broken line IIIb of  FIG. 3A ,  FIG. 4A  is a cross-sectional view of the male connector housing fitted in the female connector housing, and  FIG. 4B  is an enlarged view of a portion surrounded by a broken line IVb of  FIG. 4A . 
   As shown in  FIG. 1 , the connector  1  of this embodiment includes the female connector housing  2  which holds male terminals  4  (indicated by dot-and-dash lines in  FIG. 4A ), and the male connector housing  3  receiving female terminals  5  for electrical connection to the respective male terminals  4 . 
   The female connector housing  2  is, for example, a resin-molded part in which the male terminals  4  are insert molded, and this female connector housing  2  is fixed to an equipment, and includes a hood portion  6  of a generally rectangular tubular shape surrounding the male terminals  4 . A pair of retaining projections  7  for retaining engagement with respective retaining member formed on the outer housing of the male connector housing  3  (described later) are formed on an outer surface of the hood portion  6 . 
   Referring to  FIG. 2 , the male connector housing  3  comprises the inner housing  20  which holds the female terminals  5 , and can be fitted in the hood portion  6  of the female connector housing  2  so that the female terminals  5  can be connected to the respective male terminals  4  held by the female connector housing  2 , and the outer housing  40  having a pair of lock arms  41  (serving as the retaining member) which are retainingly engaged with the respective engagement projections  7  of the female connector housing  2  when the inner housing  20  is fitted in the hood portion  6  of the female connector housing  2 . 
   The inner housing  20  is, for example, a resin-molded part, and is formed into a generally square pillar-shape, and has terminal receiving chambers  21  for respectively receiving and holding the female terminals  5  each having a wire W connected thereto. The terminal receiving chambers  21  extend through the inner housing  20  from a rear end thereof to a front end thereof in a direction of fitting of the male and female connector housings  3  and  2  to each other. Each female terminal  5  is inserted into the corresponding terminal receiving chamber  21  from a rear opening  21   a  thereof. 
   An elastic member  8  of a waterproof nature such for example as a ring-like rubber packing is fitted on a rear end portion of the female terminal  5  to which the wire W is connected. The elastic member  8  is press-fitted into a rear end portion of the terminal receiving chamber  21 , and is fixed thereto, thereby preventing the female terminal  5  from being withdrawn from the rear opening  21   a  of the terminal receiving chamber  21 . 
   A front holder  9  is attached to the front end portion of the inner housing  20 . The front holder  9  is held against front ends of the female terminals  5  received in the respective terminal receiving chambers  21 , thereby preventing the female terminals  5  from being withdrawn from front openings of the respective terminal receiving chambers  21 . Openings  9   a  are formed in the front holder  9 , and the female terminals  5  are accessible from the exterior in the fitting direction through these openings  9   a.    
   An elastic member  10  of a waterproof nature such for example as a ring-like rubber packing is fitted on the front end portion of the inner housing  20 . When the inner housing  20  is fitted in the hood portion  6  of the female connector housing  2 , the elastic member  10  is held in intimate contact with an inner surface of the hood portion  6  to form a waterproof seal, and also functions as a shock absorbing material for damping vibration transmitted between the hood portion  6  and the inner housing  20 . 
   The outer housing  40  is, for example, a resin-molded part, and receives the inner housing  20  therein, and is formed into such a generally square tubular shape that the outer housing  40  surrounds the received inner housing  20 , with a predetermined gap formed between its surface and the outer surface of the inner housing  20 . 
   A pair of elastic retaining piece portions  42  are formed respectively on opposed inner side surfaces of the outer housing  40 . The elastic retaining piece portion  42  has a generally L-shape, and its distal end portion extends rearwardly in the fitting direction, and its proximal end portion is integrally connected to the inner surface of the outer housing  40 . A retaining projection  43  is formed at the distal end portion of the elastic retaining piece portion  42 , and is directed toward the inside of the outer housing  40 . A pair of engagement projections  22  for retaining engagement respectively with the pair of elastic retaining piece portions  42  are formed on and project from the outer surface of the rear end portion of the inner housing  20 . 
   The inner housing  20  is inserted into the outer housing  40  through a front opening  40   a  of the outer housing  40 . As the inner housing  20  is inserted into the outer housing  40 , a rear end surface of each engagement projection  22  of the inner housing  20  is brought into abutting engagement with a front end surface of the retaining projection  43  of the corresponding elastic retaining piece portion  42  of the outer housing  40 , and elastically deforms the elastic retaining piece portion  42  in a manner to move the distal end portion of the elastic retaining piece portion  42  toward the inner surface of the outer housing  40  to which the proximal end portion of the elastic retaining piece portion  42  is integrally connected. When the inner housing  20  reaches a predetermined position, the elastic retaining piece portion  42  slides past the engagement projection  22  of the inner housing  20 , and is restored into its initial condition from the elastically-deformed condition, so that the retaining projection  43  is located at the front side of the engagement projection  22 . In this condition in which the inner housing  20  is thus received in the outer housing  40 , each elastic retaining piece portion  42  of the outer housing  40  is retainingly engaged at the rear end surface of its retaining projection  43  with the front end surface of the corresponding engagement projection  22  of the inner housing  20 . 
   Coil springs  11  (made of metal), serving as urging members, are interposed between the inner housing  20  and the outer housing  40 . The coil springs  11  are so arranged as to be expanded and contracted in a direction coinciding with the fitting direction, and these coil springs  11  resiliently urge the inner housing  20  forwardly in the fitting direction relative to the outer housing  40 . As described above, the engagement projections  22  of the inner housing  20  are retained respectively by the elastic retaining piece portions  42  of the outer housing  40 , and therefore the inner housing  20  is prevented from being withdrawn from the front opening  40   a  of the outer housing  40 . 
   A rear cover  12  is mounted in a rear opening of the outer housing  40  to close this rear opening, and the wires W, connected respectively to the female terminals  5  held in the inner housing  20 , can be led to the exterior through the rear cover  12 . 
   The structure of fitting the female connector housing  2  and the male connector housing  3  together will be described with reference to  FIGS. 3 and 4 . 
     FIG. 3A  is a cross-sectional view showing the male connector housing  3  in its non-fitted condition in which the male connector housing  3  is not fitted in the female connector housing  2 . In this non-fitted condition, the inner housing  20  is resiliently urged forwardly in the fitting direction by the coil springs  11 , and is received within the outer housing  10 , with the engagement projections  22  retained by the respective elastic retaining piece portions  42  of the outer housing  40 . 
   A plurality of ribs  23  and a plurality of rib reception portions  44  are formed respectively on the outer surface of the inner housing  20  and the inner surface of the outer housing  40  which are opposed to each other in a direction perpendicular to the fitting direction, and each rib  23  and the corresponding rib reception portion  44  project toward each other. In order that the inner housing  20  can be smoothly inserted into the outer housing  40 , a clearance (small gap) C 1  is formed between each rib  23  and the corresponding rib reception portion  44  as shown in  FIG. 3B . The inner housing  20 , received within the outer housing  40 , is contacted at the ribs  23  with the rib reception portions  44  of the outer housing  40 , or is disposed in such a manner that the clearance C 1  is formed between each rib  23  and the corresponding rib reception portion  44 . This inner housing  20  is resiliently urged by the coil spring  11 , and is supported by the outer housing  40  in such a manner that the inner housing  20  will not move relative to the outer housing  40  in a direction perpendicular to the fitting direction, and can move forward and rearward in the fitting direction. 
   A plurality of limitation projections  24  are formed on the outer surface of the front end portion of the inner housing  20 , and are arranged generally symmetrically with respect to a centerline (or axis) of the inner housing  20 . A front end surface  24   a  of each of the limitation projections  24  is defined by a slanting surface which is slanting forwardly in the fitting direction in a manner to gradually approach the centerline of the inner housing  20 . Slanting surfaces  6   a  which can be mated respectively with (or held in surface-to-surface contact with) the slanting surfaces  24   a  of the limitation projections  24  of the inner housing  20  are formed on an inner surface of the opening of the hood portion  6  of the female connector housing  2 . 
   As the male connector housing  3  is moved to be fitted into the female connector housing  2 , the inner housing  20  of the male connector housing  3  is fitted into the hood portion  6  of the female connector housing  2 . At this time, the hood portion  6  of the female connector housing  2  enters a space between the outer surface of the inner housing  20  of the male connector housing  3  and the inner surface of the outer housing  40  thereof. Then, the slanting surfaces  24   a  of the limitation projections  24  of the inner housing  20  are mated respectively with the slanting surfaces  6   a  of the hood portion  6 , so that the position of the inner housing  20  relative to the female connector housing  2  is fixed. 
     FIG. 4A  shows the male connector housing  3  fitted in the female connector housing  2 . At the time when the male connector housing  3  is completely fitted in the female connector housing  2 , the hood portion  6  of the female connector housing  2  further enters the space between the outer surface of the inner housing  20  of the male connector housing  3  and the inner surface of the outer housing  40  thereof, and the engagement projections  7 , formed on the outer surface of the hood portion  6 , are retainingly engaged with the lock arms  41  of the outer housing  40 . The inner housing  20 , fixed to the female connector housing  2 , is moved rearward in the fitting direction relative to the outer housing  40  by an amount larger than an amount of superimposing of each rib  23  and the corresponding rib reception portion  44  on each other in the fitting direction. 
   In this fitted condition, the inner housing  20  and the outer housing  40  are supported by the hood portion  6  of the female connector housing  2  independently of each other. And, the inner housing  20  is moved rearward in the fitting direction relative to the outer housing  40  as described above, and by doing so, each rib  23  of the inner housing  20  is displaced in the fitting direction, and is completely brought out of registry with the corresponding rib reception portion  44 . As a result, a gap C 2 , corresponding to a height of the rib reception portion  44 , is formed between the rib  23  and the inner surface of the outer housing  40 , and also a gap C 3 , corresponding to a height of the rib  23 , is formed between the rib reception portion  44  and the outer surface of the inner housing  20  as shown in  FIG. 4B . Both of the gap C 2  and the gap C 3  are larger than the clearance C 1 , and therefore in this condition, a larger gap is formed between the inner housing  20  and the outer housing  40  than in the non-fitted condition of the male connector housing  3  (in which it is not fitted in the female connector housing  2 ). 
   Thus, the inner housing  20 , holding the female terminals  5 , is disposed out of contact with the outer housing  40 , and therefore even when vibration is applied to the connector  1 , so that relative motion of the female and male connector housings  2  and  3  occurs, the load of the outer housing  40  will not act on the male and female terminals  4  and  5 . As a result, a load, acting on the male and female terminals  4  and  5 , is reduced, thereby reducing wear of contact portions of these terminals. 
   And besides, the slanting surfaces  24  formed respectively on the limitation projections  24  of the inner housing  20 , as well as the slanting surfaces  6   a  formed on the hood portion  6  of the female connector housing  2 , intersect the fitting direction, and therefore relative motion of the inner housing  20  and the female connector housing  2  (which are fitted together) both in the fitting direction and in a direction perpendicular to the fitting direction is suppressed. Furthermore, when the mating slanting surfaces  24   a  and  6   a  are worn, the inner housing  20  is inserted deeper into the female connector housing  2 , so that the slanting surfaces  24   a  are kept mated with the respective slanting surfaces  6   a , and therefore the relative motion is suppressed for a long period of time. 
   Furthermore, the coil springs  11  resiliently urge the inner housing  20  forwardly in the fitting direction in such a manner that the slanting surfaces  24   a , formed respectively on the limitation projections  24  of the inner housing  20 , are pressed respectively against the slanting surfaces  6   a  formed on the hood portion  6  of the female connector housing  2 . With this construction, the slanting surfaces  24   a , formed respectively on the limitation projections  24  of the inner housing  20 , are always positively kept mated respectively with the slanting surfaces  6   a  formed on the hood portion  6  of the female connector housing  2 , and therefore relative motion of the inner housing  20  and the female connector housing  2  (which are fitted together) both in the fitting direction and in the direction perpendicular to the fitting direction is positively suppressed. 
   The present invention is not limited to the above embodiment, and suitable modifications, improvements and so on can be made. 
   The present application is based on Japan Patent Application No. 2005-106361 filed on Apr. 1, 2005, the contents of which are incorporated herein for reference.