Abstract:
An ultrathin connector that is easy to assemble has a base in which a plurality of positioning concavities are provided side by side in a lower surface thereof, connection terminals having a shape obtained by bending a needle-like metal material in two and joining it under pressure, these connection terminals being positioned in the positioning concavities so that two free end portion project from the base, a pressure-sensitive adhesive tape that is pasted on, and integrated with, the lower surface of the base and fixes the connection terminals to the base, and a control lever in which a pair of rotary shafts that protrude coaxially from the end surfaces on both sides are rotatably supported on the base and which lifts wider portions of the connection terminals.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a connector, and more particularly to an ultrathin connector used for connecting a flexible printed board of a cellular phone or the like. 
         [0003]    2. Description of the Related Art 
         [0004]    Japanese Patent No. 2,692,055 describes an example of conventional electric connector for a flexible board that is suitable as a connector for connecting flexible printed boards. 
         [0005]    Thus, in this connector, a large number of contacts are press fitted from a side into a housing and arranged in row, a pressure is applied to a flexible printed board with a lid-shaped pressure application member, and the flexible printed board is electrically connected to the contacts. 
         [0006]    However, with the above-described electric connector for a flexible printed board, where the device thickness is wished to be decreased, for example, to 1.0 mm or less, the entire housing has to be reduced in size. In this case, the possibilities of molding the housing into a cylindrical shape from a resin so as to enable the insertion of contacts from the side thereof are limited. In addition, even if a cylindrical housing of a small size is molded, it would be very difficult to press fit and assemble a large number of contacts from the housing opening. The resultant problem is that a limitation is placed on the thickness reduction of the device. 
       SUMMARY OF THE INVENTION 
       [0007]    With the foregoing in view, it is an object of the present invention to provide an ultrathin connector that is easy to assemble. 
         [0008]    The connector in accordance with the present invention that resolves the above-described problems comprises a base in which a plurality of positioning concavities are provided side by side in a lower surface thereof; connection terminals having a shape obtained by bending a needle-like metal material in two and joining it under pressure, these connection terminals being positioned in the positioning concavities so that at least one free end portion projects from the base; a tape cover that is pasted on, and integrated with, the lower surface of the base and fixes the connection terminals to the base; and a control lever in which a pair of rotary shafts that protrude coaxially from end surfaces on both sides are rotatably supported on the base and which lifts one free end portion of the connection terminals. 
         [0009]    In accordance with the present invention, it is not necessary to mold a cylindrical base so as to insert the connection terminal under pressure. Therefore, molding of the base is facilitated. At the same time, because it is not necessary to insert the connection terminals into the base under pressure, the assembling operation is facilitated. As a result, obstacles for reducing the connector thickness are removed and an ultrathin connector can be obtained. 
         [0010]    As an embodiment of the present invention, positioning may be performed by causing a rotation fulcrum formed by caulking in the vicinity of the bent portion of the connection terminal to abut against a reference surface provided inside the positioning concavity of the base. 
         [0011]    With such embodiment, positioning accuracy of the connection terminals with respect to the base is increased, and a connector with high assembling accuracy can be obtained. 
         [0012]    As another embodiment of the present invention, a pair of elastic arm portions may be extended parallel to each other in the same direction from end surfaces on both sides of the base, and the rotary shafts of the control lever may be rotatably engaged with respective bearing portions provided at the distal ends of the elastic arm portions. 
         [0013]    With such embodiment, a biasing force of the elastic arm portion acts upon the control level assembled with the elastic arm portions to control the position. Therefore, play of the control lever can hardly occur. 
         [0014]    As yet another embodiment of the present invention, a taper surface facilitating the assembling of the control lever may be formed at the distal end surface of the elastic arm portion. 
         [0015]    With such embodiment, the elastic arm portions are elastically deformed and spread when the control level is assembled. The resultant advantage is that the assembling operation of the control lever is facilitated. 
         [0016]    As yet another embodiment of the present invention, the rotary shafts of the control lever may be rotatably mated with support clasps that are engaged with and fixed to the end surfaces on both sides of the base. 
         [0017]    With such embodiment, an external force applied to the control lever is supported by the support clasps. The resultant advantage is that the supporting strength becomes higher. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]      FIG. 1  is a perspective view illustrating an embodiment of the connector in accordance with the present invention; 
           [0019]      FIG. 2  is an exploded perspective view of the connector shown in  FIG. 1 ; 
           [0020]      FIG. 3A ,  FIG. 3B  and  FIG. 3C  are a plan view, a bottom view, and a partial enlarged bottom view of the connector shown in  FIG. 1 ; 
           [0021]      FIG. 4A  and  FIG. 4B  are a perspective view and a partial enlarged view of the base shown in  FIG. 2 ; 
           [0022]      FIG. 5A  and  FIG. 5B  are a perspective view and a partial enlarged view, from a different angle, of the base shown in  FIG. 2 ; 
           [0023]      FIG. 6A  and  FIG. 6B  are a perspective view and a partial enlarged view, from another angle, of the base shown in  FIG. 2 ; 
           [0024]      FIG. 7A ,  FIG. 7B  and  FIG. 7C  are a perspective view and partial enlarged views from below of the base shown in  FIG. 2 ; 
           [0025]      FIG. 8A  and  FIG. 8B  are a plan view and a partial enlarged perspective view of the base shown in  FIG. 2 ; 
           [0026]      FIG. 9A  and  FIG. 9B  are a perspective view and a front view of the first connection terminal shown in  FIG. 2 ; 
           [0027]      FIG. 10A ,  FIG. 10B  and  FIG. 10C  are a perspective view, a front view, and a plan view of the second terminal shown in  FIG. 2 ; 
           [0028]      FIG. 11A ,  FIG. 11B  and  FIG. 11C  are a perspective view, a partial enlarged perspective view, and an enlarged left-side view of the control lever shown in  FIG. 2 ; 
           [0029]      FIG. 12A ,  FIG. 12B  and  FIG. 12C  are a plan view of the control lever shown in  FIG. 11 , and a cross-sectional view along a B-B line and a cross-sectional view along a C-C line in  FIG. 12A ; 
           [0030]      FIG. 13A ,  FIG. 13B  and  FIG. 13C  are a perspective view, a partial enlarged perspective view, and an enlarged left-side view of the core of the control lever shown in  FIG. 11 ; 
           [0031]      FIG. 14A ,  FIG. 14B  and  FIG. 14C  are a perspective view and a plan view of the support clasp shown in  FIG. 2 ; 
           [0032]      FIG. 15A  and  FIG. 15B  are a perspective view and a partial enlarged perspective view of the flexible printed board; 
           [0033]      FIG. 16A ,  FIG. 16B  and  FIG. 16C  is a perspective view before the operation of the connector, a perspective view during the operation, and a perspective view immediately before the flexible printed board is inserted; 
           [0034]      FIG. 17A  and  FIG. 17B  are a perspective view and a partial enlarged perspective view immediately before the control lever is locked; 
           [0035]      FIG. 18A  and  FIG. 18B  are a perspective view and a partial enlarged perspective view of a state in which the control lever is locked; 
           [0036]      FIG. 19A  and  FIG. 19B  is a plan view illustrating the state in which the control lever is locked and a cross-sectional view along a B-B line in  FIG. 19A ; 
           [0037]      FIG. 20A ,  FIG. 20B ,  FIG. 20C  and  FIG. 20D  are a plan view before the operation of the control lever, and a cross-sectional view along a B-B line, a cross-sectional view along a C-C line, and a cross-sectional view along a D-D line in  FIG. 20A ; 
           [0038]      FIG. 21A ,  FIG. 21B ,  FIG. 21C  and  FIG. 21D  are a plan view illustrating a state in which the control level is pulled up, and a cross-sectional view along a B-B line, a cross-sectional view along a C-C line, and a cross-sectional view along a D-D line in  FIG. 21A ; 
           [0039]      FIG. 22A ,  FIG. 22B ,  FIG. 22C  and  FIG. 22D  are a plan view illustrating a state in which a flexible printed board is connected to the connector, and a cross-sectional view along a B-B line, a cross-sectional view along a C-C line, and a cross-sectional view along a D-D line in  FIG. 22A ; and 
           [0040]      FIG. 23A ,  FIG. 23B ,  FIG. 23C  and  FIG. 23D  are a plan view illustrating a state in which a flexible printed board of different thickness is connected to the connector, and a cross-sectional view along a B-B line, a cross-sectional view along a C-C line, and a cross-sectional view along a D-D line in  FIG. 23A . 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0041]    An embodiment of the connector in accordance with the present invention will be described below with reference to the appended drawings ( FIG. 1  through  FIG. 23 ). 
         [0042]    As shown in  FIG. 1  and  FIG. 2 , the connector of the present embodiment in general comprises a base  10 , a first connection terminal  20 , a second connection terminal  30 , a control lever  40 , and support clasps  50 ,  60 . 
         [0043]    The maximum height of the connector of the present embodiment is 0.50 mm, the maximum width is 4.65 mm, and the maximum length is 13.20 mm. 
         [0044]    As shown in  FIG. 4  through  FIG. 8 , in the base  10 , first engagement slits  11   a ,  11   a  are formed by extending elastic arm portions  12 ,  13  parallel to each other in the same direction from an edge portion on one side of both side end surfaces of a base body  11 . Further, as shown in  FIG. 4  through  FIG. 7 , second engagement slits  11   b ,  11   b  are formed in the vicinity of the two side end surfaces in the base body  11 . Further, engagement protrusions  14   a ,  14   b  are provided in a protruding condition, so as not to face each other, at side surfaces adjacent to the first and second slits  11   a ,  11   b . Positioning concavities  15 ,  16  that serve to mate with the below-described first and second connection terminals  20 ,  30  and position the terminals are provided alternately in a zigzag fashion on the rear surface of the base body  11 . Further, as shown in  FIG. 5  and  FIG. 6 , a reference surface  17   a  for position control is formed at the farther side of a guide tongue piece  17  that protrudes forward from the rear surface of the base  10 . On the other hand, rotary shafts  45 ,  45  of the below-described control lever  40  are rotatably supported on the distal end portions of the elastic arm portions  12 ,  13 , and respective thrust bearing portions  12   a ,  13   a  are formed. Further, taper surfaces  12   b ,  13   b  are formed at the distal end surfaces of the elastic arm portions  12 ,  13 , respectively. 
         [0045]    As shown in  FIG. 9 , the first connection terminal  20  is connected to the first conductive portion  72  provided at one end edge of the below-described flexible substrate  70  ( FIG. 15 ). For this purpose, a needle-shaped metal member that is punched out from a band-shape thin metal sheet is bent in two, and a zone close to a bent portion  21  is fixed by caulking to obtain a rotation fulcrum  22 , whereby a movable contact piece  24  having a predetermined spring force is formed at a terminal body portion  23 . As a result, in the first connection terminal  20 , the first conductive portion  72  of the flexible printed board  70  can be sandwiched by the terminal body portion  23  and the movable contact piece  24 . 
         [0046]    Likewise, as shown in  FIG. 10 , the second connection terminal  30  is connected to a second conductive portion  73  positioned in the vicinity of the distal end edge of the below-described flexible printed board  70  ( FIG. 15 ). For this reason, a needle-shaped metal member that is punched out from a band-shape thin metal sheet is bent in two, and a zone close to a bent portion  31  is fixed by caulking to obtain a rotation fulcrum  32 , whereby a movable contact piece  34  having a predetermined spring force is formed at a terminal body portion  33 . As a result, in the second connection terminal  30 , the second conductive portion  73  of the flexible printed board  70  can be sandwiched by the terminal body portion  33  and the movable contact piece  34 . 
         [0047]    The distal end portion of the movable contact piece  34  reliably abuts against a cam portion  46  of the below-described control lever  40  ( FIG. 11 ), and serves as a wider portion  35  of a plane, almost trapezoidal shape so as to prevent the occurrence of twisting. In particular, the wider portion  35  forms taper surfaces on both sides at the distal end. The resultant advantage is that the movable contact piece  34  of the second connection terminal  30  can be smoothly inserted into an insertion hole  47  of the control lever  40 . 
         [0048]    The first and second connection terminals  20 ,  30  are mated with and positioned by guide concavities  15 ,  16 , respectively, that are formed in the rear surface of the base  10 . Further, the second connection terminals are fixed to the base  10  by heating and fusing a pressure-sensitive adhesive tape to the rear surface of the base  10 . At this time, as shown in  FIG. 7 , of the back surface of the base  10 , a reference surface  15   a  for positioning that is formed in the position corresponding to the rotation fulcrum  22  of the first connection terminal  20  positions the first connection terminal  20 , and a positioning protrusion  16   a  that is provided in a protruding condition in a position corresponding to the rotation fulcrum  32  of the second terminal  30  positions the second terminal  30 . The resultant advantage is that the assembling accuracy is high. 
         [0049]    The control lever  40 , as shown in  FIG. 11  through  FIG. 13 , is manufactured by insert molding a metal core  41 . As shown in  FIG. 13 , the core  41  is punched and pressed from a sheet-like metal material, and an axial core portion  43  that serves as the below-described rotary shaft  45  and a hook portion  44  for locking are formed at respective ends of a core body  42 . In particular, the axial core portion  43  is pressed to produce a substantially round cross section from a square cross section. The resultant advantage is that the number of production operations is small and the rotary shaft  45  with a high position accuracy can be obtained. However, in order to prevent the molded resin from peeling, a pair of fine grooves  43   a  are left, these grooves facing the outer circumferential surface of the axial core portion  43 . This is done to improve the flow or resin and prevent the molded resin from peeling. In addition, in order to increase the rigidity of the core body  42 , a reinforcing step  42   a  is formed continuously along edge portion of one side thereof. Further, in order to prevent the molded resin from peeling from the core body  42 , a plurality of steps  42   b  for peeling prevention are provided with a predetermined pitch at the edge portion of the remaining side. 
         [0050]    Further, as shown in  FIG. 11 , by insert molding the core  41 , the axial core portion  43  is covered with the molded resin and a rotary shaft  45  of a round cross section is obtained. Further, the core body  42  is covered with the molded resin, and an insertion hole  47  partitioned by a cam portion  46  is formed. In this case, the rotary shaft  45  and the cam portion  46  are located in concentric positions, rather that on the same axis. Further, as shown in  FIG. 3C  and  FIG. 19B , blocking protrusions  48  that will engage with notched portions  74  of the below-described flexible printed substrate  70  are integrally molded at both side end portions of the back surface of the control lever  40 . 
         [0051]    Further, the rotary shafts  45 ,  45  of the control lever  40  are pushed against the taper surfaces  12   b ,  13   b  ( FIG. 7A ) formed at the elastic arm portions  12 ,  13  of the base  10 , and the elastic arm portions  12 ,  13  are spread. The rotary shafts  45 ,  45  are then engaged with the bearing portions  12   a ,  13   a  of the elastic arm portions  12 ,  13 , thereby rotationally supporting the control lever  40 . 
         [0052]    As shown in  FIG. 14A  and  FIG. 14B , the support clasps  50 ,  60  have shapes that are axially symmetrical with respect to each other and are engaged with and fixed to the base  10 . The support clasps  50 ,  60  rotatably support the control lever  40  and are used when the base  10  is fixed to a printed substrate (not shown in the figure). 
         [0053]    Thus, the support clasp  50  ( 60 ) is provided with a pair of engagement holes  52   a ,  52   b  ( 62   a ,  62   b ) that can engage respectively with the engagement protrusions  14   a ,  14   b  of the base at one end side of a support clasp body  51  ( 61 ), and an extension portion  55  ( 65 ) is formed via a joining portion  54  ( 64 ) at the other end side. The extension portion  55  ( 65 ) has a locking protrusion  56  ( 66 ) provided in a protruding condition at one end thereof that is positioned in the vicinity of the joining portion  54  ( 64 ), and a soldering portion  57  ( 67 ) is formed at the other end thereof. 
         [0054]    Further, the support clasps  50 ,  60  are fixed by engaging the engagement holes  52   a ,  52   b ,  62   a ,  62   b  thereof with respective engagement protrusions  14   a ,  14   b  of the base  10 . As a result, the rotary shafts  45 ,  45  of the control lever  40  are fitted, so that they can slide in the vertical direction, into the bearing grooves  53 ,  63  and are rotatably supported therein. The locking hoop portions  44 ,  44  of the control lever  40  can be locked with respective locking protrusions  56 ,  66  of the support clasps  50 ,  60 . 
         [0055]    The support clasps  50 ,  60  of the present embodiment are provided in positions such that the soldering portions  57 ,  67  and locking protrusions  56 ,  66  are separated from each other. For this reason, even when the soldering portions  57 ,  67  are soldered to the printed substrate, the molten solder is prevented from flowing and adhering to the locking protrusions  56 ,  66 . Further, in the present embodiment, the support clasp bodies  51 ,  61  and extending portions  55 ,  65  are joined by wide joining portions  54 ,  64  and rigidity thereof is increased. Because of this, an external force applied to the bearing grooves  53 ,  63  via the rotary shaft  45  is dispersed via the joining portions  54 ,  64  and, therefore, the support clasps  50 ,  60  are prevented from being deformed when the flexible printed board  70  is pulled or rotated. 
         [0056]    In the flexible printed board  70 , as shown in  FIG. 14 , the first and second conductive portions  72 ,  73  are provided side by side alternately in a zigzag fashion at the edge portion of the distal end of the insertion portion  71  positioned at one end side of the flexible printed board. At the edge portion at the other end of the flexible printed board  70 , there are provided two rows of first and second connection pads  75 ,  76  that are electrically connected via printed wiring (not shown in the figure) to the first and second conductive portions  72 ,  73 . 
         [0057]    A method for using the connector of the present embodiment will be described below. 
         [0058]    As shown in  FIG. 20D , in the connector before the operation, the rotary shaft  45  of the control lever  40  is biased by the elastic arm portion  12  of the base  10  and located in the lowermost portion of the bearing groove  63  ( FIG. 20C ). As a result, the control lever  40  has no play. Further, the cam portion  46  of the control lever  40  is so designed that it is not in contact with the movable contact piece  34 . This is done to prevent the occurrence of plastic deformation in the second connection terminal  30  and prevent the operation characteristics from changing under the effect of vibrations during transportation. 
         [0059]    As shown in  FIG. 21 , when the control lever  40  of the connector is pulled up, the rotary shaft  45  of the control lever  40  rotates about the lowermost portion of the bearing groove  53  as a fulcrum. Because of this, the cam portion  46  of the control lever  40  pulls up the wider portion  35  of the second connection terminal  30 , and the insertion portion  71  of the flexible printed board  70  can be inserted. At this time, because the cam portion  46  has a substantially square cross section, when the control lever  40  is pulled up to a predetermined position, a desired click feel can be obtained, thereby providing the operator with the sense of security. 
         [0060]    For example, where the insertion portion  71  of the flexible printed board  70  with a thickness of 0.09 mm is inserted along the terminal body portion  33  of the second connection terminal  30 , the distal end of the insertion portion  71  abuts against, and is positioned by, the reference surface  17   a  for position control ( FIG. 19B ) formed in the rear surface of the base  10 . Further, the first conductive portion  72  of the insertion portion  71  is pushed between the terminal body portion  23  of the first connection terminal  20  and the movable contact piece  24 , and the second conductive portion  30  is positioned between the terminal body portion  33  of the second connection terminal  30  and the movable contact piece  34 . 
         [0061]    Where the control lever  40  is then brought down, the rotary shaft  45  of the control  40  that is mated with the bearing groove  53  is rotated and the cam portion  46  moves obliquely downward. For this reason, the movable contact piece  34  of the second connection terminal  30  pushes by its own spring force the second conductive portion  73  down and squeezes and electrically connects the second conductive portion  73  between the terminal body portion  33  of the second connection terminal  30  and the movable contact piece  34 . When the control lever  40  is further rotated, as shown in  FIG. 17  and  FIG. 18 , the locking hook portion  44  of the control lever  40  is locked by the locking protrusion  56  of the support clasp  50 , thereby completing the connection operation. As a result, the blocking protrusions  48  formed at both ends of the lower surface of the control lever  40  are engaged with the notched portions  74  of the flexible printed board  70  and block the flexible printed board. At this time, the cam portion  46  of the control lever  40  is not pressed against the movable contact piece  34  of the connection terminal  30  and produces no effect on the contact pressure of the movable contact piece  34 . 
         [0062]    Further, as shown in  FIG. 22C , the rotary shaft  45  of the control lever  40  does not return to the lowermost position of the bearing groove  53  and is stopped in the intermediate portion of the bearing groove  53 . Because of this, as shown in  FIG. 22D , the elastic arm portion  12  assumes a raised state. Therefore, a bias force of the elastic arm portion  12  acts upon the control lever  40 , thereby preventing any play of the control lever  40 . 
         [0063]    Likewise, as shown in  FIG. 21 , the control lever  40  is pulled up, and the insertion portion  71  of the flexible printed board  70  with a thickness of 0.15 mm is inserted. Further, as shown in  FIG. 23C , where the control lever  40  is lowered and fixed, the rotary shaft  45  of the control lever  40  is stopped in the lowermost portion of the bearing groove  53  and does not move down. At this time, the cam portion  46  of the control lever  40  is not pressed against the movable contact piece  34  and produces no effect on the contact pressure. Further, because the elastic arm portion  12  is raised to the uppermost portion, as shown in  FIG. 23D , a larger bias force of the elastic arm portion  12  acts upon the control lever  40 , and play of the control lever  40  can be prevented more reliably. 
         [0064]    In the present embodiment, the rotary shaft  45  of the control lever  40  is mated, so that it can slide in the vertical direction, with the bearing groove  53  of the support clasp  40 . Because of this, flexible boards of different thickens can be inserted and connected. Furthermore, even when there is a spread in thickness of the flexible board  70 , the control lever  40  produces no effect on contact pressure, and the movable contact pieces  24 ,  34  are pressed against the first and second conductive portions  72 ,  73  of the flexible board  70  by a predetermined contact pressure. Therefore, with the present embodiment, a connector of high utility and high contact reliability can be obtained. 
         [0065]    Further, with the present embodiment, the soldering portions  57 ,  67  of the support clasps  50 ,  60  are connected to the ground wire of the printed board, and the metal core  41  of the control lever  40  is locked by the locking protrusions  56 ,  66  of the support clasps  50 ,  60  via the hook portions  44  for locking, thereby enabling magnetic shielding. 
         [0066]    A case in which the control lever is attached via the support clasps to the base is explained above, but the present invention is not limited to such case. Thus, a configuration may be employed in which bearing grooves extending in the vertical direction are directly provided in extending portions that extend from end surfaces at both sides of the base, and the rotary shaft of the control lever can rotate in the bearing grooves and may be mated and supported so that it can slide in the vertical direction. 
         [0067]    Further, in the present embodiment, a case is explained in which the connection terminal and support clasp that are components separate from the base are subsequently attached to the base, but such method is not limiting. Thus, the connection terminal may be insert molded with the base, or the support clasp may be insert molded with the base, or both the connection terminal and the support base may be insert molded with the base. 
         [0068]    The connector in accordance with the present invention can be applied not only to a flexible printed board, but also to other printed boards.