Abstract:
A movable connector is provided which is more compact, reduces the attachment area on the board, increases the strength of attachment to the board, and increases the reliability of electrical connections. The movable connector has an insulating housing, contacts held in the vicinity of the mating portion of this housing, and retention legs (metal attachment members) held in the housing and fastened to the board. Each retention leg has a mounting portion mounted on the housing, and an attachment portion attached to the board and connected to the mounting portion in a position that is removed from the surface of the circuit board in the upward direction. Since the contacts and retention legs are flexible with respect tot he housing, a movable connector is obtained that can move over the surface of the board so that any positional deviation with the mating connector can be absorbed.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to an electrical connector which is attached to the circuit board, and more specifically relates to a movable connector which absorbs positional deviations between the connectors when engaged with a mating connector.  
         BACKGROUND OF THE INVENTION  
         [0002]    Connectors of this type generally have a floating mechanism which is used to absorb, i.e., compensate for, positional deviation between connectors. For example, the movable connector disclosed in Japanese Utility Model Publication No. 5(1993)-33479 is known. In this movable connector, an insulative housing has openings which are formed in the vicinity of both ends of a base portion formed as a flange. Attachment members which have a pair of elastic legs are molded as integral portions of the insulating housing inside these openings. This movable connector is mounted on a board by the elastic legs being inserted into attachment holes in the board and fastened in a manner that allows displacement. Consequently, slight positional deviations that occur during engagement with a mating connector can be absorbed by the displacement of the movable connector, so that correct engagement is possible.  
           [0003]    In the movable connector, since the attachment members are made of an insulative synthetic resin, the size of the elastic legs must be increased in order to achieve increased retention strength of the connector on the panel. Consequently, the size of the movable connector is also increased. Furthermore, since the elastic legs are made of a synthetic resin, the legs cannot be soldered to the board, so that there are limits to the attachment strength.  
         SUMMARY OF THE INVENTION  
         [0004]    The present invention was devised in view of the above. An object of the present invention is to provide a compact movable connector in which the attachment area on the circuit board is small, the strength of the attachment to the board is high, and the reliability of electrical connections is also high.  
           [0005]    The movable connector of the present invention has an insulating housing which is carried on a circuit board. The housing has a mating portion that engages with a mating connector attached from a direction perpendicular to the surface of the circuit board. At least two flat-plate metal attachment members are provided which have mounting portions that are fastened to the housing and attachment portions that extend from these mounting portions and are fastened to the circuit board. The contact(s) are fastened to the housing in the vicinity of the mating portion so that these contact(s) are movable relative to the housing along the surface of the circuit board. The attachment portions of the attachment members are connected to the mounting portions in position that are separated from the surface of the circuit board in an upward direction so that the attachment portions can move along the surface relative to the mounting portions. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]    The invention will now be described by way of example with reference to the accompanying figures of which:  
         [0007]    [0007]FIG. 1 is a front view of the movable connector of the present invention.  
         [0008]    [0008]FIG. 2 is a plan view of the movable connector shown in FIG. 1.  
         [0009]    [0009]FIG. 3 is a side view of the movable connector shown in FIG. 1.  
         [0010]    [0010]FIG. 4 is a bottom view of the movable connector shown in FIG. 1.  
         [0011]    [0011]FIG. 5 is a sectional view of the movable connector along line  5 - 5  in FIG. 2.  
         [0012]    [0012]FIG. 6 is a partial enlarged sectional view of the movable connector along line  6 - 6  in FIG. 2.  
         [0013]    [0013]FIG. 7 is a front view of the housing used in the movable connector shown in FIG. 1.  
         [0014]    [0014]FIG. 8 is a plan view of the housing used in the movable connector of the present invention.  
         [0015]    [0015]FIG. 9 is a side view of the housing shown in FIG. 8.  
         [0016]    [0016]FIG. 10 is a bottom view of the housing shown in FIG. 8.  
         [0017]    [0017]FIG. 11 is a front view of the alignment plate.  
         [0018]    [0018]FIG. 12 is a plan view of the alignment plate shown in FIG. 11.  
         [0019]    [0019]FIG. 13 is a side view of the alignment plate shown in FIG. 11.  
         [0020]    [0020]FIG. 14 is a bottom view of the alignment plate shown in FIG. 11.  
         [0021]    [0021]FIG. 15 is a sectional view of the alignment plate along line  15 - 15  in FIG. 12.  
         [0022]    [0022]FIG. 16 is a front view of one of the retention legs.  
         [0023]    [0023]FIG. 17 is a side view of the retention leg shown in FIG. 16.  
         [0024]    [0024]FIG. 18 is a bottom view of the retention leg shown in FIG. 16.  
         [0025]    [0025]FIG. 19 is a partial enlarged sectional view of the housing along line  19 - 19  in FIG. 10.  
         [0026]    [0026]FIG. 20 is a partial enlarged sectional view of the housing along line  20 - 20  in FIG. 9.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0027]    Below, a preferred embodiment of the movable connector (hereafter referred to simply as a “connector”) of the present invention will be described in detail with reference to the attached figures.  
         [0028]    Referring first to FIGS.  1 - 4 , the connector  1  has a substantially rectangular insulating housing  2  which is mounted on a circuit board P, a plurality of contacts  4  which are held in this housing  2 , and an insulative alignment plate  100  which is anchored to the housing  2  and which positions the contacts  4 . The housing  2  will now be described with reference to FIGS. 7 through 10 as well. The housing  2  has a mating portion  12  which engages a mating connector (not shown in the figures) in the upper portion of the main body  20  of the housing  2 .  
         [0029]    Rectangular wide portions which protrude outward from the main body  20  are formed on both end portions of the main body  20 . The bottom surfaces  22 , of these wide portions  8 , are located on the surface  5  of the board P. The wide portions  8  protrude from both side walls  18 , of the main body  20  so that these wide portions  8  face each other on the sides of the side walls  18  (FIGS. 8 and 10). Anchoring projections  30  which have upward-facing surfaces  30   a  (Figure &amp;) are formed on the facing surfaces  28  of these wide portions  8  in positions that face each other roughly in the centers of the wide portions  8 . Latching arms  102  of the alignment plate  100  are anchored on these anchoring projections  30 .  
         [0030]    As is shown in FIGS. 1, 5, and  7 , a rectangular cut-out  26  which cuts across the main body  20  is formed via step portions  24  in the side walls  18  between the wide portions  8 . The shape of this cut-out  26  on the sides of the wide portions  8  has recesses and projections, as is shown most clearly in FIG. 10. This is done in order to prevent deformation caused by molding sinks for example. Contact sections  48  of the contacts  4 , which extend toward the alignment plate  100  from the mating portion  12 , are disposed in a portion of this cut-out  26 . The contact sections  48  disposed in this portion are prevented by this cut-out  26  from interfering with the housing  2  during the movement of the housing  2  during engagement with the mating connector. Accordingly, there is no restriction of the floating function of the connector  1 . In other words, when the connector is engaged with the mating connector, the housing  2  can move freely along the surface  5  of the board P without interfering with the contacts  4  fastened to the board P, so that positional deviation between the connectors can be absorbed. Furthermore, the alignment plate  100  is disposed in the step portions  24 ; however, this will be described in greater detail below.  
         [0031]    Next, the mating portion  12  of the housing  2  will be described. The plan shape of the mating portion  12  of the housing  2  is shown in FIGS. 2 and 8. This mating portion  12  will be described with additional reference being made to FIGS. 5 and 6. An engaging recess  34  with a long slender plan shape, into which the mating connector is inserted is formed in the mating portion  12  of the housing  2 . As is shown most clearly in FIG. 5, the depth of the engaging recess  34  reaches an intermediate point in the direction of height of the upper region  36 . Furthermore, the upper region  36  indicates a portion that extends from the cut-out  26  to the upper end or the engaging surface  12   a,  of the housing  2 .  
         [0032]    A rib  38  which extends in the direction of length is formed in the engaging recess  34  so that this rib protrudes as an integral portion of the housing  2  in the mating direction of the connector  1  from the center of the bottom surface  40  of the engaging recess  34  (FIG. 5). Grooves  42  extending in the vertical direction for the installation of the contacts  4  are formed in both sides of this rib  38  at specified intervals along the direction of length of the rib  38 . These grooves  42  extend to the vicinity of the tip end of the rib  38 , which has a curved surface. Furthermore, contact receiving holes (hereafter referred to simply as “receiving holes”)  44  which communicate with the engaging recess  34  and cut-out  26  are formed in the vertical direction (in FIG. 5) in the upper region  36  in alignment with the grooves  42 . The contacts  4  are pressfit in these receiving holes  44  from below, and disposed in the grooves  42 . Furthermore, tapered surfaces  34   a  are formed in engaging recess  34  in the vicinity of the engaging surface  12   a.    
         [0033]    Furthermore, as is shown most clearly in FIG. 6, guide holes  64  which have a substantially rectangular plan shape are formed in both end portions of the engaging recess  34  along the mating direction. Guide projections (not shown in the figures) on the mating connector whose tip ends have a convergent shape are inserted into these guide holes  64  when the connectors are mated with each other, so that the connectors are aligned with each other prior to the electrical engagement of the contacts with each other. These guide holes  64  have tapered surfaces  64   a  in the portions that open at the engaging surface  12   a . The tapered surfaces  64   a  have a more gradual inclination than the tapered surfaces  34   a . In other words, the area that is projected in the mating direction is larger in the case of the tapered surfaces  64   a  than in the case of the tapered surfaces  34   a , so that the guide holes  64   a  and guide projections can compensate for a larger positional deviation. Discharge holes  68  which have a rectangular cross-sectional shape, and which communicate with the cut-out  26 , are formed in the bottom surfaces  66  of the guide holes  64 . After the connector  1  is soldered to the board P, the solder flux is cleaned away. These discharge holes  68  are used to discharge the cleaning liquid from the guide holes  64 .  
         [0034]    Next, the contacts  4  disposed in the grooves  42  will be described. The contacts  4  are shown most clearly in FIGS. 5 and 6; these contacts  4  are formed by stamping and forming metal plates into a long slender shape. The contacts  4  have tip end portions that are fastened to the rib  38  or contact portions  46  that make contact with the mating contacts, and contact sections  48  which are bent at an intermediate point of each contact  4  and which drop downward toward the board P. Two types of contacts  4   a  and  4   b  are used in which the shape of the bent portion that is bent at an intermediate point is different. Specifically, there are contacts  4   a  which have a large bent portion  49 , and contacts  4   b  which have a small bent portion  51 .  
         [0035]    The contact sections  48   a  of the contacts  4   a  are disposed on the outside of the alignment plate  100  (described later), while the contact sections  48   b  of the contacts  4   b  are disposed on the inside of the alignment plate  100 . These contacts  4   a  and  4   b  are alternately disposed along the direction of length of the rib  38 . A plurality of barbs  53  are formed on both side edges of the contact portions  46  of the contacts  4  facing the receiving holes  44 , in positions that are separated along the direction of length of the contacts  4 . When the contacts  4  are press-fitted in the receiving holes  44 , these barbs  53  engage the inside walls of the receiving holes  44 , so that the contacts  4  are fastened in place in the receiving holes  44 . Specifically, the contacts  4  are fastened to the housing  2  by press-fitting in the vicinity of the mating portion  12 .  
         [0036]    Next, the alignment plate  100  will be described. Furthermore, in this description, reference will also be made to FIGS. 11 through 15. The alignment plate  200  is molded from an insulative material such as a synthetic resin, and has a  5  substantially rectangular flat plate portion  104 . A plurality of guide holes  106  which are used to guide the contacts  4  are formed in this plate portion  104  (see FIGS. 12 and 15).  
         [0037]    The guide holes  106  have shapes that converge inward from square openings  110  formed in the surface of the plate portion  104 . These guide holes  106  communicate with small holes  110   a  that pass through to the opposite side of the plate portion  104 . The contact sections  48  of the contacts  4  are guided by the guide holes  106 , and are passed through these small holes  110 . The guide holes  106  are arranged to align with the contact sections  48 . The contact sections  48   a  of the contacts  4   a  are disposed in the outside rows of guide holes  106 , and the contact sections  48   b  of the contacts  4   b  are disposed in the inside rows of guide holes  106 .  
         [0038]    Furthermore, positioning posts  108  which are passed through positioning holes  17  in the board P (see FIGS. 1 and 5) are formed on both end portions of the side edge  104   a  on one side of the plate portion  104 . These positioning posts  108  position the alignment plate  100  in the correct position on the board P, and are used in order to achieve a smooth disposition of the contact sections  48  in the through-holes  3  of the board P. For this purpose, the system is arranged so that the tip ends of the positioning posts  108  engage with the board P before the tip ends of the contact sections  48  when the connector  1  is mounted on the board P. Ribs  108   a  which extend in the vertical direction are formed so that they protrude from the outside surfaces of the positioning posts  108 . This is done in order to ensure that the positioning posts  108  will not interfere with the inside walls of the positioning holes  17  when the positioning posts  108  are inserted into the positioning holes  17 .  
         [0039]    Latching arms  102  are integrally formed as protruding portions on the four comers of the plate portion  104  such that these latching arms  102  stand upright. Outward-facing projections  112  are formed on the front end portions of the latching arms  102 . These projections  112  engage with the engaging projections  30  of the housing  2  when the alignment plate  100  is disposed on the step portions  24  of the housing  2  to secure the alignment plate  100  to the housing  2 .  
         [0040]    Next, the retention legs  70 , which are attached to the insides of the wide portions  8  of the housing  2  will be described with reference to FIGS. 16 through 16. Furthermore, this description will also make reference to FIGS. 19 and 20. Each retention leg  70  is a flat plate member which is integrally formed by stamping from a single metal plate. Each retention leg  70  has a base portion  72 , a pair of arms  74  which extend downward from the lower ends of both sides of this base portion  72 , and a long slender attachment portion  76  which extends further than the arms  74  from the base portion  72  at a point between these arms  74 .  
         [0041]    The base portion  72  consists of an upper portion  78  which is on the upper side in FIG. 16, and a lower portion  80  which is wider than the upper portion  78 , and which is located on the lower side beyond cut-outs  82  formed in the side edges. Barbs  78   a  and  80   a  are respectively protrude in the plane of the plate from both side edges of the upper portion  78  and lower portion  80 . In FIG. 16, the arms  74  that extend downward from both end portions of the lower portion  80  are formed so that the end edges  74   a  of the arms  74  extend perpendicular to the length of the arms  74 . Slots  64  are formed between these arms  74  and the attachment portion  76  is located between the arms  74 . The slots  84  have a shape in which the lower portions of the slots  84  are shifted to the outside at an intermediate point along the length.  
         [0042]    The lower portion of the attachment portion  76  expands outward, and a plurality of barbs  76   a  are formed on this expanded portion so that these barbs face outward. A cut-out  86  which extends from the tip end of the attachment portion  76  to roughly the middle of the attachment portion  76  is formed along the central axial line extending in along the length of the attachment portion  76 . The tip end portion of this cut-out  86  is narrow, while the rear end portion is relatively wide. The portions of the attachment portion  76  that are split by the cut-out  86  are offset from each other in the direction of thickness of the retention leg  70  in the vicinity of the upper end of the cut-out  86 , and in the cut-out area (FIG. 17).  
         [0043]    Next, the attachment grooves  50  in the housing  2  to which the above-mentioned retention legs  70  are attached will be described with reference to FIGS. 19 and 20. The attachment grooves  50  are grooves that are formed in the vertical direction in the wide portions  8  of the housing  2 . These grooves  50  open in the bottom surface  22 . As is shown in FIG. 19, each attachment groove  50  consists of an inside portion  52  which has a relatively narrow width, an intermediate portion  54  with a relatively large width which is adjacent to this inside portion  52 , and a receiving portion  56  which reaches the bottom surface  22  and which is slightly wider than the intermediate portion  54 . Furthermore, the central portion  58  of each attachment groove  50  which extends in the vertical direction has a gap that is sufficiently large to accommodate the positionally- shifted attachment portion  76 ; moreover, the side portions  60  positioned on both sides of the central portion  58  are formed so that there is a gap that is slightly larger than the plate thickness.  
         [0044]    When the retention legs  70  are inserted into these attachment grooves  50 , the base portions  72  and arms  74  of the retention legs  70  advance along the side portions  60  of the attachment grooves  50 . Furthermore, these base portions  72  and arms  74  are referred to as the “mounting portions”  73 , and the retention legs  70  are mounted on the housing  2  by means of these mounting portions  73 . In order to insert the retention legs  70  into the attachment grooves  50 , the end portions  74   a  of the arms  74  of the retention legs  70  are pressed and inserted from beneath the housing  2  a tool (not shown in the figures).  
         [0045]    When the upper portion  78  and lower portion  80  of the base portion  72  are respectively positioned in the inside portion  52  and intermediate portions  54  of the corresponding attachment groove  50 , the barbs  78   a  and  80   a  respectively interfere and engage the inside walls of the inside portion  52  and intermediate portion  54 . As a result, the retention leg  70  is fastened in place in the corresponding attachment groove  50 . The positionally- shifted attachment portion  76  is positioned in the central portion  58  of the corresponding attachment groove  50 . Since the retention legs  70  are plate shaped portions, the attachment portions that are attached to the housing  2  are small. Accordingly, the housing  2  can be made more compact. Furthermore, the cut-outs  62  are portions where portions of the mold used to reinforce the mold pins that mold the attachment grooves  50  are disposed.  
         [0046]    In order to attach the connector  1  to the board P, the contacts  4  are first aligned with the through-holes  3  in the board P. The attachment portions  76  of the retention legs  70  are also aligned with the anchoring holes  16  in the board P. Both the contacts  48  and retention legs  70  are urged through the connector  1 , into the respectively corresponding through-holes  3  and anchoring holes  16  from above the board P. When the attachment portions  76  are urged into the anchoring holes  16 , the split tip end portions of the attachment portions  76  are inserted while being offset inward toward each other, and the barbs  76   a  on the attachment portions  76  interfere and engage with the inside walls of the anchoring holes  16 . As a result, the retention legs  70  are fastened to the board P. Since the tip end portions of the split attachment portions ? 6  are positionally shifted relative to each other, there is no interference with the mutual deformation of the tip end portions even if the tip end portions are deformed so that they approach each other inside the anchoring holes  16 . Accordingly, smooth Insertion can be accomplished without any need for an excessive insertion force. Since the retention legs  70  are formed from metal plates, the retention legs  70  themselves have improved strength, and are resistant to breaking (unlike legs formed from a synthetic resin). Since the contact sections  48  of the contacts  4  and attachment portions  76  of the retention legs  70  attached to the board P are respectively fastened to the board P by soldering, the attachment strength is greatly increased.  
         [0047]    When the connector  1  thus fastened is to be engaged with a mating connector, the guide projections of the mating connector and the guide holes  64  of the connector  1  are first engaged. Specifically, the guide projections are inserted into the guide holes  64 . As a result, both connectors are aligned and the positional deviation of the connectors is absorbed. In this case, the housing  2  moves along the surface  5  of the board P as a result of the flexing of the contact sections  48  of the contacts  4  and the flexing of the attachment portions  76 , so that this positioning is possible.  
         [0048]    In the attachment members  70 , slots  84  are present between the attachment portions  76  and the arms  74 , and the attachment portions  76  have a long slender shape. Accordingly, the housing  2  can move in the direction perpendicular to the thickness of the retention legs  70 , i.e., in the left-right direction in FIG. 16. Furthermore, since the attachment portions  76  can easily flex in the direction of thickness of these portions as well, the housing  2  can move in all directions along the surface  5  of the board P, so that any positional deviation can be absorbed.  
         [0049]    The foregoing illustrates some of the possibilities for practicing the invention. Many other embodiments are possible within the scope and spirit of the invention. It is, therefore, intended that the foregoing description be regarded as illustrative rather than limiting, and that the scope of the invention is given by the appended claims together with their full range of equivalents.  
         [0050]    The metal attachment members may be integrally formed by stamping metal plates; furthermore, the mounting portions of the metal attachment members may be constructed from a base portion which is fastened to the housing and a pair of arms that extend from this base portion, and the attachment portions may be constructed so that these attachment portions extend further than the arms from the base portion at a point between the arms.  
         [0051]    The term “flat-plate-form” does not require that the shape be a completely smooth plate shape, but includes states in which there is some displacement from the surface of the plate in some portions.