Electrical connector including coaxial cable management system

An electrical connector includes a dielectric housing and a plurality of terminals mounted therein. A conductive ground blade is mounted in the housing and includes at least a pair of positioning arms projecting therefrom for engaging the metallic shields of a pair of coaxial cables. An independent cable management member is mounted on the housing and includes a partition extending between the positioning arms to separate the coaxial cables and maintain the metallic shields near the positioning arms.

FIELD OF THE INVENTION
 This invention generally relates to the art of electrical connectors and,
 particularly, to a connector for a plurality of coaxial cables and
 including a system for terminating the metallic shields of high speed
 cables, such as the metallic braids of the cables.
 BACKGROUND OF THE INVENTION
 A typical high speed cable includes a center conductor or core surrounded
 by a tube-like inner dielectric. A shield is disposed outside the inner
 dielectric for shielding and/or grounding the cable. The shield typically
 is a tubular metallic braid. However, one or more longitudinal conductive
 wires have also been used and are commonly called "drain wires." An
 insulating jacket surrounds the composite cable outside the shield.
 Various types of connectors are used to terminate high speed cables. The
 connectors typically have contacts which are terminated to the center
 conductor or core of the cable. The connectors also have one form or
 another of a terminating member for terminating the metallic shield of the
 high speed cable, usually for grounding purposes. A typical system in such
 connectors may terminate the metallic shield to the terminating member by
 soldering or welding. Other systems use crimping procedures to crimp at
 least a portion of the terminating member securely to the metallic braid.
 With the ever-increasing miniaturization of the electronics in various
 industries, such as in the computer and telecommunications industries,
 along with the accompanying miniaturization of electrical connectors,
 considerable problems have been encountered in terminating miniature high
 speed cables, particularly in terminating the metallic shield of the
 cable. For instance, the outside diameter of a small coaxial cable may be
 on the order of 0.090 inch. The outside diameter of the inner dielectric
 surrounding the conductor/core may be on the order of 0.051 inch, and the
 diameter of the center conductor/core may be on the order of 0.012 inch.
 Coaxial cables having even smaller dimensional parameters have been used.
 The problems in terminating small coaxial cables often revolve around
 terminating the metallic shield of the cable. For instance, if soldering
 methods are used, applying heat (necessary for soldering) in direct
 proximity to the metallic shield can cause heat damages to the underlying
 inner dielectric and, in fact, substantially disintegrate or degrade the
 inner dielectric. If conventional crimp-type terminations are used,
 typical crimping forces often will crush or deform the inner dielectric
 surrounding the center conductor/core of the cable. In either case, damage
 or deformation of the inner dielectric will change the electrical
 characteristics of the cable.
 The above problems are further complicated when the metallic shield of the
 high speed cable is not terminated to a cylindrical terminating member,
 but the shield is terminated to a flat terminating member or contact. For
 instance, an example of terminating the metallic shield or braid of a
 coaxial cable to a flat ground member is shown in U.S. Pat. No. 5,304,069,
 dated Apr. 19, 1994 and assigned to the assignee of the present invention.
 In that patent, the metallic braids of a plurality of coaxial cables are
 terminated to a ground plate of a high speed signal transmission terminal
 module. The conductors/cores of the coaxial cables are terminated to
 signal terminals of the module. Other examples are shown in U.S. Pat. No.
 5,711,686, dated Jan. 27, 1998; U.S. Pat. No. 5,716,236, dated Feb. 10,
 1998; U.S. Pat. No. 5,718,607, dated Feb. 17, 1998; U.S. Pat. No.
 5,725,387, dated Marc. 10, 1998; and U.S. Pat. No. 5,785,555 dated Jul.
 28, 1998, all of which are assigned to the assignee of the present
 invention.
 The present invention is directed to further improvements in managing the
 termination of high speed coaxial cables, including the termination of the
 metallic shields of a plurality of cables to a terminating member, such as
 a ground blade.
 SUMMARY OF THE INVENTION
 An object, therefore, of the invention is to provide a new and improved
 electrical connector which includes a system for terminating the metallic
 shields of high speed cables.
 In the exemplary embodiment of the invention, the connector includes a
 dielectric housing having a front mating face and a rear terminating face,
 a plurality of terminal-receiving passages extending generally between the
 faces, and a blade-receiveng passage extending generally between the
 faces. A plurality of terminals are received in the terminal-receiving
 passages. A conductive ground blade is received in the blade-receiveng
 passage. The ground blade includes at least a pair of positioning arms
 projecting from the ground blade at the rear terminating face of the
 housing for engaging the metallic shields of a pair of coaxial cables. An
 independent cable management member is mounted on the housing and includes
 a partition extending between the positioning arms to separate the coaxial
 cables and maintain the metallic shields near the positioning arms.
 As disclosed herein, the ground blade is generally planar and includes a
 slot. The cable management member includes a wall portion projecting
 through the slot and between the positioning arms to provide an abutment
 shoulder to prevent the ground blade from backing out of the
 blade-receiving passage. The ground blade includes a pair of the
 positioning arms projecting from each opposite side thereof, with a
 partition on the cable management member extending between each pair of
 arms. This defines four quadrants for accommodating four coaxial cables.
 Four terminal-receiving passages are provided in the housing aligned with
 the four quadrants for receiving four signal terminals.
 The invention also contemplates that a shield be disposed about at least a
 portion of the housing and engaging at least a portion of the cable
 management member to hold the member on the housing. The cable management
 member includes at least one locating projection disposed in a locating
 recess in the housing. The locating projection is on an arm of the cable
 management member, and the shield engages the arm to hold the cable
 management member on the housing.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
 Referring to the drawings in greater detail, and first to FIGS. 1-5, the
 invention is embodied in an electrical connector, generally designated 14,
 which includes a dielectric housing, generally designated 15,
 substantially surrounded by a front shield, generally designated 16, and a
 back shield, generally designated 17. The housing is a one-piece structure
 unitarily molded of dielectric material such as plastic or the like. Each
 shield 16 and 17 is a one-piece structure stamped and formed or drawn of
 conductive sheet metal material.
 The connector is an input/output (I/O) electrical device wherein front
 shield 16 defines a front mating face 18 of the connector, and rear shield
 17 defines a rear terminating face 20. The front face actually is formed
 by a shroud 22 of shield 16 surrounding forwardly projecting contact
 portions of three rows of data transmission terminals, generally
 designated 24. The data transmission terminals project through
 terminal-receiving passages 26 in the connector housing and have rear tail
 portions 25. A conductive ground blade 28 projects through a
 blade-receiving passage 30 in the connector housing. A pair of high speed
 signal terminals 32 project through a pair of terminal-receiving passages
 34 in the housing on each opposite side of ground blade 28. Terminating or
 tail portions 36 (FIG. 2) of high speed signal terminals 32 project
 rearwardly of rear shield 17 on a rear platform 40 of the connector
 housing.
 Only one of the high speed signal terminals 32 is shown in FIGS. 1 and 2,
 but it is understood that a pair of the high speed signal terminals are
 disposed on each opposite side of ground blade 28. Similarly, only six
 data transmission terminals 24 are shown in FIG. 1, but thirty of such
 terminals may be arranged in three rows of passages 26 in the connector
 housing.
 Front shield 16 has a pair of rearwardly projecting tabs 42 on both the top
 and bottom thereof. The tabs project rearwardly of a base plate 46 of the
 front shield through notches 47 in a base plate 48 of the rear shield. The
 top tabs are bent downwardly in the direction of arrows "A" (FIG. 2), and
 the bottom tabs are bent upwardly in the direction of arrow "B". This
 secures the front and rear shields rigidly together about connector
 housing 15.
 Before proceeding with further details of the interior of the connector
 assembly, reference is made to FIGS. 3 and 4 which show details of
 conductive ground blade 28. The blade is stamped and formed of sheet metal
 material. As can be seen, the blade is elongated and generally planar to
 define a long ground plate. Barbs 50 are stamped at opposite edges of the
 ground blade for establishing an interference fit within blade-receiving
 passage 30 of the housing. A pair of positioning arms 52 project from each
 opposite side of the ground blade at a rear terminating end 54 thereof.
 Each positioning arm includes a stamped window 56. The positioning arms
 are arcuately shaped for engaging a metallic shield, such as metallic
 braids of coaxial cables. The positioning arms are soldered to the
 metallic shields, and windows 56 allow for the flow of solder material
 through the arms and into engagement with the shields. A slot 58 is formed
 in ground blade 28. The slot is open at rear end 54 of the blade and has a
 closed end 58a which defines an abutment shoulder, for purposes described
 hereinafter.
 FIG. 5 shows a cable management member, generally designated 60, according
 to the invention. The cable management member includes a pair of
 oppositely extending partitions or walls 62 which extend between the upper
 and lower pairs of positioning arms 52 at the rear end of ground blade 28
 as seen in FIGS. 1 and 2. The partitions have sloped entry surfaces 63 to
 guide the cables into position and catches 65 to retain the cables after
 they have been inserted therein. As such, partitions 62 and positioning
 arms 52 are effective to provide a cable management system which is
 divided into four quadrants for receiving four coaxial cables 64 (FIG. 2)
 terminated to tails 36 of the four high speed signal terminals 32 in the
 four passages 34 in the connector housing, as described above. In essence,
 the tails 36 of the four high speed signal terminals are aligned with the
 four quadrants defined by partitions 62 of cable management member 60 and
 positioning arms 52 of ground blade 28. The cable management member has a
 pair of longitudinal flanges 66 on each opposite side thereof to define
 channels 68 for receiving the planar portions of the ground blade on
 opposite sides of slot 58 (FIGS. 3 and 4). A front abutment surface 70
 (FIG. 5) of cable management member 60 abuts against the closed end 58a of
 slot 58 to prevent the ground blade from backing out of its passage in the
 connector housing. In other words, after the ground blade is inserted into
 the rear of housing 15, assembly of cable management member 60 to the
 housing causes abutment shoulder 70 of the cable management member to
 engage abutment end 58a of slot 58 in the ground blade, whereby the cable
 management member is effective to prevent the ground blade from backing
 out of the housing. Still referring to FIG. 5, cable management member 60
 is assembled to connector housing 15 by means of a pair of arms 72 having
 forwardly directed locating projections 74. The locating projections are
 received in locating recesses in the connector housing, as described
 hereinafter. Alternatively, the ground blade 28 and the cable management
 member 60 may be preassembled, and then the ground blade/cable management
 member subassembly is installed onto the rear of housing 15.
 FIGS. 6-8 show the interior components of connector 14, i.e. with front and
 rear shields 16 and 17, respectively, removed. Arms 72 of cable management
 member 60 are located in slots 76 in a rear face 78 of housing 15. It can
 be seen how partitions 62 of the cable management member cooperate with
 positioning arms 52 of ground blade 28 to provide a cable management
 system defining four quadrants between the partitions and the positioning
 arms. FIGS. 9 and 10 show that connector housing 15 includes a pair of
 locating recesses 80 above and below blade-receiving passage 30 for
 receiving locating projections 74 (FIG. 5) of cable management member 60.
 The locating projections can be press-fit into locating recesses 80, if
 desired, to provide a preliminary holding means for the cable management
 member. It should be understood that rear shield 17 abuts against the rear
 of arms 72 (FIG. 5) to hold the cable management member in its assembly
 position. Finally, FIGS. 9 and 10 show that platform 40 of the housing has
 notches 82 to facilitate the termination of discrete electrical wires to
 tail portions 25 of data transmission terminals 24.
 As is known in the art, a typical coaxial cable 64 (FIG. 2) has an inner
 conductor 84, an inner dielectric 86 surrounding the inner conductor, a
 metallic shield or braid 88 surrounding the inner dielectric and an outer
 insulating jacket 90 surrounding the metallic shield. In terminating cable
 64 to tail portion 36 of one of the high speed signal terminals 32, and
 terminating metallic shield 88 of the conductor to arms 52 of ground blade
 28, outer jacket 90 of the cable is removed to expose a portion of
 metallic shield 88 at a location for engaging one of the positioning arms
 52 and a portion of the inner dielectric 86 is removed to expose the inner
 conductor 84. The shield is either cut or folded back to expose a distal
 end of inner conductor 84 for solder connection to tail portion 36 of one
 of the high speed terminals 32. The cable is then positioned in the
 quadrant defined by the partition 62 and the positioning arm 52. When so
 placed, the metallic braid of the coaxial cable is juxtaposed with the
 positioning arm 52 and can be easily soldered thereto with the window 56
 allowing for the flow of solder material into engagement with the shield.
 In addition, the inner conductor is aligned such that it is in
 juxtaposition with the tail portion 36 of signal terminal 32 and can be
 easily soldered together. Although only one cable 64 is shown in FIG. 2,
 four such cables can be very easily terminated to ground blade 28 and
 terminal tails 36, because partitions 62 of cable management member 60
 cooperate with positioning arms 52 of the ground blade to divide the
 termination area of the cables into four quadrants for properly
 positioning the cables.
 It will be understood that the invention may be embodied in other specific
 forms without departing from the spirit or central characteristics
 thereof. The present examples and embodiments, therefore, are to be
 considered in all respects as illustrative and not restrictive, and the
 invention is not to be limited to the details given herein.