Abstract:
A dual connector arrangement made up of two discrete multiport connectors, each with an external shield, that may be vertically stacked, the first of the two connectors being a conventional single row multiport connector, and the second of the two connectors being a single row multiport connector with a vertical extension that houses a single row of contact tails and that fits behind the first multiport connector and shields the contact tails of the second multiport connector when it is seated on top of the first multiport connector.

Description:
This application is a Divisional of non-provisional application Ser. No. 09/255,854, filed Feb. 23, 1999. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to the field of electrical connectors, and in particular to an arrangement for providing multiple rows of input/output ports on a printed circuit board or interface card without the need for a stacked multiport connector having an internal shield. The invention also relates to an arrangement for installing a plurality of single row multiport modular jack connectors on a printed circuit board or interface card to form a high density multiport connector array, and to connectors that permit such stacking. 
     2. Description of Related Art 
     Electrical connectors known as modular phone receptacles or jacks have been available for many years. Although connectors of this type were originally designed for use in telephone systems, they have found wide acceptance in a variety of other contexts. For example, modular jacks referred to as RJ connectors, which may be incorporated into single port or multiport arrangements, are now commonly used as input/output (I/O) interface connectors for enabling computers to communicate with each other and with a variety of peripheral equipment, and in particular as connectors between a local area network (LAN) and an appropriately configured interface card. 
     In order to receive a corresponding modular plug, the conventional modular jack or RJ connector is generally made up of a socket housing which includes a plug-receiving opening, opposed top and bottom surfaces joined by opposed side surfaces extending from the opening to a back surface, and a plurality of stamped, metallic elongated contacts mounted in the housing for engaging contacts of the corresponding plug. Each contact in this type of connector includes a contact mating portion at one end extending diagonally into the socket, a vertically extending lead portion at the other end, and a horizontally extending intermediate portion between the contact mating portion and the lead portion. Generally, the lead portions of the contacts are inserted directly into openings in the interface card and soldered in place. 
     U.S. Pat. No. 5,775,946 (Briones), herein incorporated by reference, discloses a shielded multiport connector having a row of ports capable of receiving RJ-type connector plugs. The connector disclosed in this patent, which is illustrated in FIGS. 1A-1C, uses a single molded housing having multiple openings and a one-piece external shield in order to increase port density without significantly increasing assembly costs. 
     In particular, as illustrated in FIGS. 1A-1C, the conventional single row multiport RJ connector includes a molded plastic housing  1  and an external shield  2 . Molded plastic housing  1  includes a plurality of ports or receptacle openings  3  (shown in FIG. 1B) each accommodating a plurality of contacts  4  including mating portions  5  that extend into the openings to mate with corresponding contacts of an RJ plug connector, intermediate portions (not shown) that extend rearwardly out of the openings, and contact tails  6  that extend vertically from the intermediate portions through the bottom of the connector to be terminated to a circuit board on which the connector is mounted by, for example, mounting posts  7 . 
     Shield  2  is fitted over the housing  1  following assembly of the contacts  4  to the connector and may be secured to the housing in a variety of ways. As illustrated, the shield  2  is a one-piece shield that includes a foldable rear panel  8  that fits over the back of the housing and that includes horizontal extensions  9  from which project latching tabs  10  that engage openings  11  in the bottom of the housing and cooperate with an inwardly extending lower front panel  12  as described in U.S. Pat. No. 5,775,946 to secure the shield directly to the housing, although the present invention may also be applied, by way of example, to one-piece shields in which the foldable rear panel is secured to adjacent side panels of the shield, rather than directly to the housing, and the adjacent panels are secured to the housing, or to shields made up of separate panels. Extending from the shield are circuit board ground tabs  13  and various optionally arranged side, top, and/or bottom ground tabs  14  for engaging a panel and ground tabs  15  for engaging shields of respective RJ plug connectors inserted into openings  3 . 
     As is apparent from FIG. 1B, the openings for the plug connectors are asymmetric. The tops of the openings include notches  16  arranged to receive latching members on the mating RJ plug connectors, and the space remaining at the corners of the housing adjacent the notches may, if required, be utilized to receive LED indicator lights  17  whose terminals  18  extend to the rear and downward in the same manner as the contacts. Although illustrated with the notches at the top of the connector, the orientation of the ports may also be reversed so that the notches and LEDs are located at the bottom of the connector. 
     In order to further increase port density while maintaining substantially the same footprint on the circuit board, it is known to modify the single row connector by adding a second row of ports, the top and bottom rows of ports all being enclosed by a single common external shield. Examples are disclosed in U.S. Pat. Nos. 5,531,612 (Goodall), 5,562,507 (Kan), 5,639,267 (Loudermilk), as well as in commonly assigned U.S. patent application Ser. No. 09/149,567, filed Sep. 9, 1998. 
     The adjacent rows of ports in these connectors generally have vertically symmetric orientation, i.e., the notches  16  are at the bottom and top of the connector, in order to minimize the height of the connectors and to prevent the latches in adjacent rows from facing each other, which would make removal of mating plug connectors difficult. As a result, however, the contacts in adjacent rows are close together, resulting in cross-talk between the facing contacts, and necessitating that a shield be placed between the contacts. The difficulty in assembling the contacts and shields to the housing has led to a number of different approaches to stacked multiport connector design, including the modular approach taken in U.S. patent application Ser. No. 09/149,567, but all such designs represent an increase in connector complexity and also in assembly difficulty, that is disproportionate to the increased port density obtained by stacking the rows of the connector. 
     In addition, because the conventional multiple row multiport connector has a larger number of pins than the conventional single row connector, the number of pins that must be located or aligned with corresponding openings on the circuit board is correspondingly greater, increasing the difficulty of assembling the connector to the circuit board. 
     SUMMARY OF THE INVENTION 
     It is accordingly a first objective of the invention to provide an arrangement that permits the number of input/output or communications ports on a printed circuit board or card to be increased, relative to the number provide by a conventional single row multiport connector, without substantially increasing the footprint of the ports on the circuit card, and without requiring the internal shielding or assembly difficulties of a stacked multiport connector. 
     It is a second objective of the invention to provide a multiport RJ connector arrangement for a printed circuit board or card that utilizes two discrete stackable connectors rather than a single stacked multiport connector, and which therefore allows additional rows to be retrofitted onto and existing connector. 
     It is a third objective of the invention to provide a multiport connector for a printed circuit board or card that can be added to an existing multiport connector arrangement to optionally double the number of ports provided by the existing multiport connector and yet that is no more difficult to install than the existing multiport connector. 
     These objectives are achieved, in accordance with the principles of a preferred embodiment of the invention, by providing a dual connector system made up of two discrete multiport connectors, each with an external shield, that may be vertically stacked, the first of the two connectors being a conventional single row multiport connector, and the second of the two connectors being a single row multiport connector with a vertical extension that houses a single row of contact tails and that fits behind the first multiport connector and protects the contact tails of the second multiport connector when it is seated on top of the first multiport connector, the external shield of the first multiport connector shielding the contacts of the first connector from those of the second connector. 
     The principles of the preferred embodiment of the invention are also implemented by providing an L-shaped multiport connector corresponding to the second multiport connector of the dual connector system, and which can be fitted on top of an existing multiport connector to increase the number of ports available in substantially the same footprint as the first multiport connector. 
     It will be appreciated by those skilled in the art that the above-described arrangement simplifies assembly of the individual connectors by eliminating the need for internal shielding because it is easier to fit an external shield onto a connector than to insert an internal shield. In addition, assembly of the connectors to the circuit board is facilitated because only a single row of pins needs to be aligned for each of the two connectors, it being easier to align a connector having a single row than one having multiple rows of contact tails. 
     Although the preferred embodiments of the invention are directed in particular to RJ type modules and connectors, such as a high speed RJ-45 connector of the type typically used on network or communications interface cards, it will be appreciated by those skilled in the art that the principles of the invention could possibly be used in other types of multiple port printed circuit board connectors. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1A is an isometric view of a conventional single row multiport RJ connector. 
     FIG. 1B is a front view of the connector of FIG.  1 A. 
     FIG. 1C is a cross-sectional side view of the connector of FIGS. 1A and 1B. 
     FIG. 2 is an isometric schematic view of a dual connector arrangement constructed in accordance with the principles of a preferred embodiment of the invention. 
     FIG. 3 is a front view of the connector of FIG.  2 . 
     FIG. 4 is a partially cross-sectional side view of a specific implementation of the dual connector arrangement of FIGS.  2  and  3 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     As illustrated in FIGS. 2 and 3, the dual connector arrangement or system of the preferred embodiment of the invention offers a substitute for conventional stacked multiport connectors in which, instead of providing a single connector housing with an internal shield between the rows of connector ports, two connectors are provided, the external shield of one connector electrically shielding the contacts of the two connectors so as to prevent cross-talk between the contacts. 
     One of the connectors is a single row multiport connector  30  having an external shield, which may be identical to the conventional single row multiport connector illustrated in FIGS. 1A-1C, or any other conventional single row multiport connector, except that alignment elements  31  are provided at or near the top of the connector. The other one of the two connectors is a single row multiport connector  32 , which may be similar in construction to the conventional multiport connectors, but which is extended rearwardly and downwardly as illustrated in FIG. 2 to fit over the lower connector  1 , and which includes alignment elements  33 , as illustrated in FIG.  3 . 
     Alignment elements  31  and  33  may respectively be in the form of pins extending downwardly from a lower surface of upper connector  32 , and complementary recesses in the top surface of connector  30 , or may take any other form which enables the elements to be used to position or align the lower connector relative to the upper connector. It is also possible to omit either or both of elements  31  and  33 , although having built-in alignment elements will in general facilitate assembly of the upper connector to the lower connector. The number and arrangement of the alignment elements, if included, is of course optional. 
     Because the lower connector  30  is shielded in conventional fashion by means of an external shield  60  corresponding to shield  2  shown in FIGS. 1A-1C, it is not necessary to provide an internal shield between the rows of ports  34 . Instead, the two connectors are assembled in the same way that conventional single row multiport connectors lacking an internal shield are assembled, and may be sold together or separately, and may be mounted to a circuit board at the same or different times. 
     As in the connector illustrated in FIGS. 1A-1C, the lower multiport connector includes a housing having a bottom wall  61  that faces the circuit board, and walls  62 , including front, back, and side walls that extend upwardly from the bottom wall  61  to a top wall  63  that is substantially parallel to the bottom wall. External shield  60  of the lower connector covers principal surfaces of the front, back, and side walls. 
     The lower multiport connector  30  is installed on the circuit board first, and the upper multiport connector  32  may be installed at any time afterwards, or added to an existing already-installed connector. Installation of the upper connector  32  simply involves positioning of the upper connector relative to the lower connector while inserting the contacts tails extending from the connector, and electrically connecting the contact tails to the openings in a conventional manner. The contact tails of the lower and upper connector may be pin contact tails arranged to be inserted into openings in the circuit board, or one or both of the lower and upper connectors may include surface-mount or other types of contact tails. Positioning and electrical connection of the contact tails completes the dual connector arrangement, providing two rows of ports. The rows of ports may be arranged, if desired, to be identical in configuration, spacing, and number, to those of a more complicated and higher cost stacked multiport connector. 
     As shown in FIG. 3, the lower and upper connectors  30 , 32  each include contacts  35 , 36  having respective mating, intermediate, and tail sections  37 - 39  and  40 - 42 . The only difference between the contacts  35  of the lower connector  30  and the contacts  36  of the upper connector  31  is that the intermediate sections  41  of the upper connector are extended rearwardly, and the tail sections  42  of the upper connector are extended downwardly, to accommodate the lower connector. In conventional stacked multiport connectors, the corresponding sections of the upper row of contacts are also extended rearwardly and downwardly, and the configuration of the contacts in the upper connector  32  may thus be similar or identical to the configuration of the upper contacts in the stacked multiport connector. 
     To accommodate the extended contacts  36  of the upper connector  31 , upper connector  32  is itself extended rearwardly and downwardly to form and inverted L-shape having a horizontal port section  43  and a vertical section  44 , which may be formed together as a single housing. As a result, the external shield  45  for the upper connector preferably also has an inverted L-shaped cross-section, including a planar top panel  46 , a conventionally configured front panel  47  with openings for the ports, L-shaped side panels  48 , and a planar rear panel  49  for respectively covering top, front, side, and rear walls of the upper connector housing. Rear panel  49  may be a foldable panel similar to rear panel  8  shown in FIGS. 1A and 1C, so that installation of the upper connector shield is accomplished in the same manner as is the case for the conventional single row multiport connector. 
     Although the stacked connector arrangement could possibly be tiered, it is preferred that the front surface of the top connector be substantially flush with the front surface of the lower connector upon assembly of the upper connector to the lower connector. From the point of view of a user of the assembled connectors, the two discrete connectors are indistinguishable from a stacked multiport connector. 
     The illustrated dual connector arrangement may also include, if required, indicator lights  50 , 51  having leads  52 , 53  in the form of light emitting diodes positioned adjacent the RJ plug connector openings. The manner in which the indicator lights are mounted may be identical to those of the prior art, except that the leads  53  of the upper connector indicator lights  51  may be extended in a manner similar to the upper connector contacts. 
     While the upper connector is illustrated as having an inverted L-shaped housing, it will be appreciated that the shaped of the upper housing could be varied within the overall inventive concept of stacking two single row multiport connectors, so long as the upper connector fits over the lower connector, and the leads of the upper connector are separated from those of the lower connector by an external shield on the lower connector. In addition, those skilled in the art will appreciate that the number of ports, specific contact configurations, and the like may be freely varied without departing from the scope of the invention. 
     Thus, having described preferred embodiments of the invention with sufficient particularity to enable those skilled in the art to easily make and use the invention, and having described several possible variations and modifications of the preferred embodiment, it should nevertheless be appreciated that still further variations and modifications of the invention are possible, and that all such variations and modifications should be considered to be within the scope of the invention.