Abstract:
In a connection assembly ( 15 ) of printed-circuit board and connector, a printed-circuit board ( 16 ) and a connector ( 17 ) can be fixed positionally accurately in relation to one another by means of position holders ( 36, 37 ) provided on the connector ( 17 ). The position holders are constituted of soldering pins ( 36, 37 ) and the printed-circuit board ( 16 ) is provided with soldering pads ( 46, 47 ) which can be connected to the opposing soldering pins ( 36, 37 ) by soldering. There is provided in this manner a connection assembly ( 15 ) of printed-circuit board and connector in which the positionally accurate fixing of a printed-circuit board ( 16 ) and a connector ( 17 ) is more easily produced and more precisely assembled than has been possible to date.

Description:
CROSS REFERENCE 
     Applicant claims priority from German patent application 19514121.0 filed Aug. 20, 1995 and German patent application 19540540.4 filed Oct. 31, 1995. 
     BACKGROUND OF THE INVENTION 
     The present invention relates to a connection assembly and to an electronic-equipment plug-in card provided with same. 
     The connection of a printed-circuit board and a connector necessitates accurate positioning of the two components in relation to one another, because on account of the general confined basic connection grid, the connecting lugs of the connector must coincided precisely in position with the connecting tracks of the printed-circuit board for soldering purposes. To date, this positionally accurate fixing of the connector on the printed-circuit board or vice versa is produced by moulding pegs onto the connector as position holders, which pegs can be plugged into locating holes in the appropriate areas of the printed-circuit board. Connectors referred to as MPC connectors can be considered known in this context. 
     This manner of holding or positionally fixing a printed-circuit board and connector relatively to one another prior to production of the soldered connection is relatively time-consuming and costly in terms of preparing for production and relatively imprecise with regard to contact positioning between the printed-circuit board terminal contact tracks and the connecting lugs of the connector. 
     Plug-in cards having such a connection are also known, for example of the kind supplied as memory cards, modem cards, fax cards or the like in PCMCIA Standard. Such plug-in cards have a plastic frame on which one or two connectors are fastened and within which the printed-circuit board inserted with electronic components mounted thereon is arranged and retained in a specifically predetermined position in the above-mentioned manner. Metal covers are attached to both sides of the plastic frame equipped in this way. 
     SUMMARY OF THE INVENTION 
     The problem addressed by the present invention is to create a connection of a printed-circuit board and connector with an electronic-equipment plug-in card provided with same, each of the kind mentioned at the outset, in which the possibility accurate fixing of printed-circuit board and connector can be more easily produced and more precisely assembled. 
     The measures in accordance with the invention avoid the relatively imprecise and nonetheless complicated provision of location holes or punched holes in the printed-circuit board. In contrast with the foregoing, the printed-circuit board is provided with soldering track areas or soldering pads which can be more accurately dimensioned and positioned. This facilitates a more positionally accurate relative location of printed-circuit board and connector, because when soldering pads of the printed-circuit board to the soldering pins which are fixed to the spacing element, the printed-circuit board floats of itself, on the fluid solder between the areas to be soldered, precisely into the correct, prescribed position. Moreover, it is easier and less expensive to attach soldering pads to a printed-circuit board than to place accurately positioned drilled holes in the printed-circuit board. 
     In the aforementioned plug-in cards, it has been proposed, in order to utilize the free space between the enclosed parts in printed-circuit boards with differently sized components, that beginning from one support area on the connector or spacer, the position holders or pegs be provided in gradually smaller diameters, so as to produce annular support areas for the printed-circuit boards, arranged in several levels at a distance from one another. For this purpose, the relevant areas of the printed-circuit board are provided with locating holes whose diameters differ as a function of the printed-circuit board used or inserted and therefore as a function of the desired position in the plug-in card. This means that a printed-circuit board provided with full diameter-size holes is penetrated by the entire peg, so that printed-circuit board takes up the lowest possible level in the plug-in card and that a printed-circuit board provided with the envisaged smallest-diameter holes will lie on the uppermost annular support area of the peg and thus take up the uppermost possible level. One or more intermediate sizes of hole can be provided together with intermediate layers of printed-circuit boards. The invention makes it possible to combine the connection of printed-circuit board and connector based on soldering pads with the option of arrangement in different levels. 
     The soldering pins can be made of an appropriate metal. Alternatively, however, in accordance with the invention, the soldering pins are made of plastic and imprinted with a soldering pad. 
     In a preferred embodiment of the present invention, the soldering pins can be connected to latch with the connector. This can be done by means of a simple plug-in connection. 
     The soldering pins can, for example, be designed in different lengths to obtain the different heights or levels. In accordance with a further embodiment of the present invention, however, the soldering pins are provided with several latching elements arranged at a distance, so the identically designed soldering pins can be used in all cases, being simply latched at different spacings onto or into the connector. 
     For example, the soldering pins can be latched as hollow pins onto corresponding pegs on the spacing element. However, the invention provides that the soldering pins be fitted to plug into latching holes in the spacing elements. 
     In addition to the supporting points with the soldering pins provide for the printed-circuit board, a plug-in card can be provided, in accordance with the invention, with additional support steps on the spacing elements for end tabs on the printed-circuit board. 
     Further details of the invention are provided in the description that follows, in which the invention is described and explained in greater detail with reference to the embodiments presented in the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a diagrammatic perspective view of a plug-in card using a connection assembly of printed-circuit board and connector in accordance with a preferred embodiment of the present invention. 
     FIGS. 2A and 2B are partially truncated perspective views of an end section of the print-circuit board in FIG. 1, but without enclosure, viewed diagonally from above and below respectively. 
     FIGS. 3A and 3B are respectively a section along Line IIIA—IIIA in FIG. 2A showing an exploded view of the individual parts and a view from below corresponding to Arrow IIIB in FIG.  3 A. 
     FIGS. 4A and 4B is a section corresponding to FIG. 3A, but in assembled condition with printed-circuit boards retained at different levels within the plug-in card, and 
     FIG. 5 is a perspective view from underneath of a connector for a connection to a printed-circuit board in accordance wit another embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The frameless electronic-equipment plug-in card  10  which is shown in assembled condition in FIG. 1, has front and rear ends spaced in directions F, R, has laterally opposite sides spaced in lateral directions L, and has upper and lower portions spaced in directions U, D. The card has an elongated, rectangular, very flat enclosure  11 , which is comprised of a recessed bottom enclosure section  12  and a recessed top enclosure section  13  connected to latch with the former. Front and rear spacers, or connectors  18 ,  17  lie at the ends of the cards. Between the two enclosure sections  12  and  13  there is arranged and fixed in place a unit  14  (FIG. 2A) only partially represented in each case, which has an approximately elongated, rectangular printed-circuit board  16  fitted, although this is not illustrated, with electronic components and two spacers  17  and  18  arranged one at each transverse end of the printed-circuit board  16  and connected to same, both of which are designed as connectors. The two connectors  17  and  18  of plug-in card  10  are accessible from outside, connector  17  being designed, for example, to accommodate a cable plug. The front end  19  (FIG. 1) of the plug-in card  10  is provided with the connector  18  which also constitutes a plug-in end for an electronic device. The two connectors  17  and  18  each have a moulded insulated body  20  in whose transverse web  28  (FIG. 2A) there is provided a socket arrangement  21  in a manner not shown in further detail. Each of the connectors is provided with a connecting lug arrangement or contact tails  22  which are arranged in a laterally-extending (L) row. With unit  14  in assembled condition, the connecting lug arrangement  22  is connected, for instance by a soldering operation, to terminal contacts or traces  23  on the printed-circuit board  16 . 
     The intention is to enable printed-circuit boards  16  fitted with different components, and thus having different overall height on at least one side, to be accommodated in the correct position within the plug-in card  10 . Several locating positions are provided for this purpose, each for a particular printed-circuit board  16 , at different levels within the plug-in card  10 . 
     As shown in FIGS. 3A and 3B, each of the spacers  17  and  18  designed as connector has, as shown here only with reference to spacer  17 , lateral longitudinal webs  26  and  27  which protrude beyond the depth of the transverse web  28  provided with the socket arrangement  21  and the connecting lug arrangement  22 . The two longitudinal webs  26  and  27  have locating holes  31  and  32  in an inside area and at a distance from one another, each provided, in an area facing the underside  29  of the longitudinal webs  26 ,  27 , with a moulded, inwardly-protruding and therefore diameter-reducing annular bead  33  which has a convex cross-section. 
     As shown in FIG. 3A, identically designed soldering pins  36  and  37  are further provided to produce the connection assembly  15 , each having an integrally formed shank  38  and a larger-diameter, flat, disk-type head  39 . The shank  38  is provided with several, for example two, annular notches  41  and  42  arranged axially spaced apart from one another, each of them having a concave cross-section. The diameter of the shank  38  and the formation of the annular notches  41  and  42  is such that the shank  38  of the soldering pins  36  and  37  is adapted to latch into the respective locating hole  31  or  32  of the connector  17 ,  18 . The annular bead  33  herein constitutes the one latching element, while any one of the annular notches  41 ,  42  constitutes the other latching element. In the embodiment represented, either the annular notch  41  leading in the plug-in direction or the annular notch  42  trailing in the plug-in direction can latch with the annular bead  33 , so that the head  39  of the soldering pin  36 ,  37  is at a different, prescribed distance from the underside  29  of the longitudinal webs  26 ,  27  of the connector  17 ,  18 . When the soldering pin  36 ,  37  is comprised of a plastic, the head  39  is provided, on its fore-part  43  facing away from the shank  38 , with a soldering pad  40  which is preferably located with its entire surface on the fore-part  43 . 
     Apart from the terminal contacts  23  and the unillustrated soldering tracks for the components in question, the printed-circuit board  16  is further provided, on its surface facing the underside  29  of the connector  17 ,  18 , with soldering pads  46 ,  47 , these being arranged at positions which, in assembled condition, lie opposite the fore-part  43  of the head  39  of the soldering pins  36 ,  37  and their soldering pads  40 . A pair of solder pads  46 ,  47  lies at each laterally (L) opposite side portion of the circuit board, while a pair of solder pins  36 ,  37  and their solder pin heads with solderable pin head areas lie at each laterally opposite side portion of the connector. 
     As shown in FIGS. 4A and 4B, a printed-circuit board  16  or  16 ′ can be retained at connectors  17 ,  18  at different levels within the plug-in card  10 . FIG. 4A shows an arrangement of the printed-circuit board  16  adjacent to the underside  29  of connector  17 ,  18 . This arrangement is obtained by plugging the soldering pins  36 ,  37  entirely into the locating hole  31 ,  32 , in which position the annular notch  42 , trailing in the plug-in direction, of the soldering pins  36 ,  37  latches with the annular bead  33  of the location holes  31 ,  32 . The printed-circuit board  16  is put in place in this latched position of the soldering pins  36 ,  37 , the soldering pads  46 ,  47  on the printed-circuit board  16  being solder-connected to the soldering pad  40  of the head  39  of the soldering pins  36 ,  37  by a soldering operation, with the aid of which further soldered connections can be made. The solder liquefied between the opposing solder pads  46 ,  47  and  40  causes the printed-circuit board  16  as it were to float into the correct position of the soldering pins  36 ,  37  retained in connectors  17 ,  18 . 
     The same applies to the position of a printed-circuit board  16 ′ further removed from the underside  29  of the connector  17 ,  18 , obtained by latching the annular notch  41 , leading in the plug-in direction, of the soldering pins  36 ,  37  with the annular bead  33  of the locating holes  31 ,  32 . The printed-circuit board  16  is solder-connected to the soldering pins  36 ,  37  in the manner described above. 
     It is to be understood that the soldering pin or pins  36 ,  37  can have more than two latching elements, i.e. axially spaced annular notches. It is also to be understood that the soldering pins  36 ,  37  can be comprised of a metal suitable for the soldering operation. Furthermore, it is also possible to arrange more than a printed-circuit board  16 ,  16 ′ within the plug-in card  10  in this manner. 
     As shown in FIG. 2B, to provide further support for the printed-circuit board  16  on the connectors such as  17 , the connectors are provided, as shown in the drawing, at areas of the longitudinal webs  26 ,  27  adjacent to the transverse web  28 , with stair-like steps  51 ,  52 , which are located in flush alignment with the leading part  43  of the soldering pins  36 ,  37  in one of the two latching positions and on which lie lateral strip-type extensions  53  and  54  of printed-circuit boards  16  and  16 ′ respectively. Depending on the chosen position of printed-circuit board  16 ,  16 ′ within the plug-in card  10 , the extensions  53 ,  54  of the printed-circuit board  16 ,  16 ′ are matched in length to the step  51 ,  52  in question. It is to be understood that the number of steps  51 ,  52  is matched to the number of latching or annular notches  41 ,  42  in the soldering pins  36 ,  37 . 
     FIG. 5 shows a connector  117 , which can be connected over connection assembly  15  to a printed-circuit board not shown in this illustration in the manner represented in FIGS. 1 to  4  with reference to the first embodiment. The connector  117 , which is provided with a connecting lug arrangement  122  projecting beyond the underside  124  of the connector  117  and is to be connected in the manner described above by soldering to the connecting tracks on a printed-circuit board, is fitted at each of the two sides of the connecting lug arrangement  122  with a soldering pin  136  and  137 , of each of which only the flat, disk-type head  139  can be seen, on whose leading part  143  a soldering pad  140  is located preferably over the whole surface. It can be seen in FIG. 5 that the lateral (in direction L) width of each pin head at its solder pad or solderable pin head area  140 , is a plurality of times greater than the lateral width of each contact tail  122 . Opposite these soldering pads  140  of the connector  117  are arranged soldering pads at positions on a printed-circuit board which correspond, in assembled condition, to the position of the leading part  143  of the head  139  of the two soldering pins  136  and  137 , as has been described in FIGS. 1 to  4  with reference to the first embodiment. It is to be understood that the leading parts  143  of the soldering pins  136  and  137  protrude above the underside  124  of the connector  117  in a manner corresponding to the position of the connecting lug arrangement  122  and that, as shown in FIG. 5, the connecting lug arrangement  122  and the leading parts  143  or soldering pads  140  of the soldering pins  136  and  137  are arranged at essentially the same level above the underside  124  of the spacer  117 . 
     It is also possible, in keeping with the embodiment in FIGS. 1 to  4 , for a connector  117  of this kind, designed in the present case as a so-called MPC connector, to be provided with the soldering pins  136  and  137  capable of latching to connect with the connector  117  at different heights. Also as in the first embodiment, more than one soldering pin  136  and  137  can be provided on each side of the connector  117 . 
     It is to be understood that other types of connector can also be fixed positionally accurately to a printed-circuit board by a connection assembly  15  of this kind in accordance with the invention.