WO2000001036A2

WO2000001036A2 - High density electrical connector with ground bus

Info

Publication number: WO2000001036A2
Application number: PCT/US1999/014987
Authority: WO
Inventors: Christopher Scott Leaman; Keith Scott Koegel; Earl Chester Myers, Jr.
Original assignee: The Whitaker Corporation
Priority date: 1998-06-29
Filing date: 1999-06-29
Publication date: 2000-01-06
Also published as: WO2000001036A9; TW434945B; WO2000001036A3; CN1308783A

Abstract

A grounding bus comprises: (a) a body section adapted for mounting to a housing of an electrical connector; (b) one or more connectors for mounting the body section to the housing prior to the connection of a conductor to the electrical connector; and (c) at least one grounding member extending from the body section to facilitate an electrical connection between a signal IDC slot on the housing and the ground bus.

Description

HIGH DENSITY ELECTRICAL CONNECTOR WITH GROUND BUS

FIELD OF THE INVENTION

The present invention relates generally to the field of electrical connectors and, more particularly, to connectors utilizing insulation displacement connection (IDC) wire termination procedures.

BACKGROUND OF THE INVENTION

Electrical connectors having insulation displacement connection (IDC) slots for terminating insulated wire conductors are known. An IDC slot is configured for a particular insulated wire such that it is less wide than the diameter of the insulated wire and slightly less wide than the diameter of the conductor within the insulation. Termination is accomplished by pressing the insulated wire between the spaced apart beams of IDC slot such that the edges of the beams displace the insulation and engage the conductor thereby establishing an electrical connection therewith. Thus, the insulated wire can be terminated without the insulation being first stripped to expose the conductor.

Examples of electrical connectors having one or more rows of IDC slots include

U.S. Patent Nos. 5,766,033 and 5,761,805. These patents disclose an electrical connector having a housing molded around sections of IDC slots disposed in first and second rows along a mating interface. The terminals have IDC slots for wires to be urged therein by termination covers from a common side of the housing. The signal IDC slots of the first row are staggered rearwardly and vertically tiered from those of the second row to facilitate wire insertion such that the wires are received in two vertical rows.

The need often arises to ground one or more of the IDC slots of an electrical connector. One approach to effect such grounding is to mold into the electrical connector a grounding network which grounds certain IDC slots. This approach, however, has several shortcomings. For example, it complicates the manufacture of the electrical connector by introducing additional conductors to be positioned and held during the molding procedure. Additionally, once the grounding network is installed and the grounded IDC slots are determined, they cannot be changed. Reconfiguring the grounded IDC slots requires expensive and time-consuming redesigns and retooling.

The lack of flexibility encountered by internal grounding networks is compounded by the need to accommodate a wide variety of grounding configurations inexpensively. That is, the competitive electrical connector market demands low-cost connectors and renders the high cost associated with reconfiguring grounding schemes among the IDC slots unacceptable.

Therefore, a need exists for a grounding system that is readily configurable without the attendant high costs of redesigning and retooling for particular grounding configurations. The present invention fulfills this need among others.

SUMMARY OF THE INVENTION

The present invention provides a grounding system which is readily configurable to allow for the selective grounding of IDC slots on new or existing electrical connectors without having to modify the electrical connector.

One aspect of the present invention is a grounding bus which is adapted to mount to an electrical connector and interact with its signal IDC slots to facilitate an electrical connection between the bus and a selection of signal IDC slots. In a preferred embodiment, the grounding bus comprises: (a) a body section adapted for mounting to a housing of an electrical connector; (b) one or more connectors for mounting the body section to the housing prior to the connection of a conductor to the electrical connector; and

(c) at least one grounding member extending from the body section to facilitate an electrical connection between a signal IDC slot on the housing and the ground bus.

The grounding members preferably are frangible, allowing them to be removed or otherwise manipulated such that their electrical contact with a signal IDC is prevented. The grounding members may take on various forms. For example, in a preferred embodiment, the grounding member is a grounding IDC slot positioned on the grounding bus such that, when the grounding bus is mounted on the electrical connector, the grounding IDC slot aligns with a signal IDC slot such that a common connector is insertable in both slots thereby electrically connecting the two. In another embodiment, the grounding member is a tab for electrically connecting the signal IDC slot to the grounding bus. Such a tab may directly contact an IDC slot, or it may be configured to contact a contact lead (which is electrically connected to an IDC slot) through a window in the housing.

Another aspect of the present invention is an electrical connector having mounted thereto a grounding bus as described above.

Yet another aspect of the invention is a method of terminating a conductor to an electrical connector of the present invention. In a preferred embodiment, the method comprises: (a) providing an electrical connector having a housing with one or more rows of signal IDC slots having mounted thereto a grounding bus of the present invention as described above; and (b) inserting a conductor, such as discrete insulated wire or ribbon cable, into one or more of the signal IDC slots such that at least one signal IDC slot is electrically connected to the ground bus.

The grounding bus of the present invention provides alternative approaches for selectively grounding signal IDC slots. In a preferred embodiment, configuring the grounding system comprises removing one or more of the grounding members from the grounding bus, thereby leaving only selected grounding members. Only the selected grounding members will facilitate an electrical connection with their respective signal IDC contacts. Alternatively, in the embodiment that uses grounding IDC slots as grounding members, the length of the conductors may be altered such that only those conductors that are to be grounded are long enough to engage both the signal IDC slots and the grounding IDC slots.

The latter approach is particularly attractive if the insertion step is performed by automated machinery such as the Champomator^® 2.6 offset terminating machine commercially available through AMP Company (Harrisburg, Pennsylvania). More specifically, the grounding bus may be mounted to an electrical connector with all of its grounding IDC slots in tact. Cutting the conductors to length and terminating them to effect selective grounding of signal IDC slots then could be accomplished through a program in the offset terminating machine. For example, in the embodiment where the grounding IDC slots are set back from the mating face of the electrical connector relative to the signal IDC slots, only those conductors long enough to reach the grounding IDC slots will provide an electrical ground connection to their respective signal IDC slots.

The grounding system of the present invention also lends itself to automation since the grounding bus is mounted to the electrical connector before terminating the conductors. More specifically, the electrical connector and grounding bus can be shipped as a unit, rather than in pieces which require further assembly (generally by hand). The connector/grounding bus unit then can be placed in an automatic termination apparatus where the conductors are inserted automatically. If the selective grounding of signal IDC slots is not accomplished by altering the length of the conductors as mentioned above, then the grounding bus may be shipped in a configured condition (i.e., with certain grounding members removed) or the user may configure it on site. Regardless, the result is a conveniently-terminated and selectively-grounded electrical connector.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric exploded view of the connector assembly containing the ground bus;

FIG. 2 is an isometric view of the ground bus of FIG. 1;

FIG. 3 is an elevation view of the housing with the ground bus and representative insulated conductors exploded therefrom;

FIG. 4 is an elevation view similar to FIG. 3 after termination of the conductors to the contacts and the ground bus;

FIG. 5 is an isometric view of another embodiment of ground bus; FIG. 6 is an enlarged isometric view of a portion of the ground bus of FIG. 5 affixed to a connector housing similar to that of FIGS. 1 to 4;

FIG. 7 is an isometric view of another embodiment of the grounding system;

FIG. 8 is an isometric view of the grounding system of FIG. 7 positioned over an electrical connector and ready for mounting thereto; and

FIG. 9 is an isometric view of the grounding system of FIG. 7 mounted on the electrical connector of FIG. 8.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Several preferred embodiments of the present invention are depicted in Figs.1-9. The particular features of the grounding system illustrated by these figures may be interchanged and varied among the different embodiment to form numerous combinations, although they should not be construed to limit the scope of the invention.

Referring now to Figs. 1 to 4, a grounding bus 60 of the present invention is depicted in combination with a high-density connector 10. The high-density connector 10 comprises an insulative housing 12 containing a first row of terminals 14 and a second row of terminals 16, 18, an insulative cover 20, first and second shells 22,24 and a pair of jackscrews 26. The housing 12 may be molded to embed body sections of the terminals as disclosed in U.S. Patent No. 5,761,805. Connector 10 defines a mating face and an opposed wire termination end. First and second shells 22,24 have cable clamping sections 28,30 that together define a cable strain relief at a rearward cable exit when clamped to a cable (not shown). Terminals 14,16,18 include contact sections 32 at a front end 34 of housing 12, and wire termination sections that include IDC slots 36,38,40 along a wire termination face 42 of housing 12 that are terminatable to respective insulated conductors (see FIGS. 3 and 4).

The grounding bus 60 includes: a body section 62; connectors for mounting the grounding bus 60 on the housing 12, which, in this embodiment, comprise fastening sections 64 at opposed ends of the body section 62; and a plurality of grounding members, which, in this embodiment, comprise grounding IDC 66 positioned along front and rear edges of body section 62. Ground bus 60 may be stamped and formed from any conductive material such as, for example, brass or stainless steel.

Fastening sections 64 include recesses 68 that will receive latching projections 44 of housing 12 therein when ground bus 60 is affixed to the housing along wire termination face 42. Upon completion of wire termination, fastening sections 46 of insulative cover 20 will similarly be latched to latching projections 44,48 of housing 12 covering ground bus 60 and all terminated wire connections along the wire termination face of the housing. Although such connectors are preferred from a simplicity standpoint, other connectors for affixing the ground bus to the electrical connector may be use, such as, for example, fasteners (e.g. , screws, rivets, and clips), adhesives, and welds.

In FIG. 2, several grounding IDC slots 66 have been removed from ground bus 60, while others remain integrally joined to body section 62 at locations selected to be terminated to respective wires 80 that are desired to be ground wires (FIGS. 3 and 4).

Polarizing features are also preferably formed on ground bus 60 that cooperate with corresponding polarizing features of housing 12. Preferably, apertures 70,72 are formed in body section 62 proximate to opposed ends thereof, with apertures 70,72 being dissimilar in shape and/or dimension to correspond to embossments 50,52 projecting from wire termination face 42 of housing 12, such that ground bus can only be fastened to housing 12 in a single selected orientation.

Referring now to FIGS. 3 and 4, first signal wires 82 are shown associated with terminals 14 of the lower row having IDC slots 36, while second signal wires 84 are associated with terminals 16 of the upper row having IDC slots 38. Ground wires 80 are associated not only with IDC slots 66 of ground bus 60, but also with respective IDC slots

40 of terminals 18 of the upper row. Thus, ground wires 80 ground terminals 18 to the ground bus to convert it into a ground terminal 18.

Ground bus 60 is configurable by removing certain IDC slots 66 leaving only a selection of grounding IDC slots 66 for grounding to the signal IDC contacts. Preferably, grounding IDC slots 66 are joined to body section 62 by frangible sections formed, for example, by scoring or notching to facilitate removal such as by a manual tool (for example, pliers). It may be preferable to sever the IDC slots 66 while the grounding bus remains in its initial, planer, stamped form before forming the grounding IDC slots 66 upwardly to be orthogonal to the plane of the body section 62. To this end, the grounding

IDC slots 66 may be severed, for example, with a punch.

As an alternative to configuring the grounding bus by removing the grounding IDC slots 66, all the grounding IDC slots may be retained if the leading ends of signal wires 84 end before the grounding IDC slots 66 of the ground bus to effect isolation therefrom. Such an approach is preferred if automated terminating apparatus is being used. For example, the Champomator^® 2.6 offset terminating machine, commercially available through AMP Company (Harrisburg, Pennsylvania), is capable of cutting the conductors to the proper length and inserting them in the various IDC slots. This way, reconfiguring the grounding of the signal IDC slots is readily effected through a simple program change.

In FIGS. 5 and 6, another embodiment of ground bus 160 is shown for mounting on connector housing 112 of connector 110. Ground bus 160 comprises a body section 162 having fastening sections 164 and orifices 166 which are sufficiently dimensioned so as not to contact the signal IDC slots of terminals 116, 118 on the connector 110. At each orifice 166 is a grounding member, which, in this embodiment, is a terminal-engaging section, such as a tab or preferably a pair of opposing tabs 168 on opposite sides of an orifice that extend toward each other. Opposing tabs 168 are adapted to frictionally and compressively engage preferably only one of the pair of beams 141 of the signal IDC slots 140 of terminals 118 at sites desired to be ground terminations. Engaging only one beam of each pair of signal IDC slots minimizes disturbance of the signal IDC termination of wires 180 with terminals 140 when ground bus 160 is affixed to the housing. Additionally, opposing tabs 168 preferably are directed upwardly to facilitate receipt of beams 141 therebetween. By engaging terminals 118 with the opposing tabs, they are made common to the grounding bus and thus converted to ground terminals. As with ground bus 60 of FIGS. 1 to 4, ground bus 160 is configurable. The grounding bus 160 is configured by removing the opposing tabs, such as with a punch or pliers, thereby allowing the upper ends of beams 139 of signal IDC slots 138 to protrude through the orifices 166 without establishing an electrical path to the ground bus 160. Unlike ground bus 60, however, ground bus 160 may be used with a housing 112 that is axially shorter than housing 12 for which ground bus 60 of FIGS. 1 to 4 is used.

Figures 7 through 9 depict yet another embodiment of the present invention. As shown, a grounding bus 700 comprises a body section 701; connectors, which, in this embodiment, comprise cut-outs 705; and grounding members, which, in this embodiment, comprise tabs 706. The tabs 706 extend from the body section 701 and are configured to contact contact leads within an electrical as described with respect to FIGS 8 and 9. Preferably, tabs 706 are frangible such that one or more of them can be removed to configure the grounding bus to the particular needs of the application.

The body section 701 is contoured to overlay a portion of electrical connector 800 (Fig. 8). To this end, it has orifices 701 that are sufficiently dimension to clear the signal

IDC slots of connector 800. Furthermore, it has first and second tiers 702, 703 to accommodate the two-tiered electrical connector shown in Figure 8. The tiers are connected via a conductive connector 707.

Figure 8 shows the grounding bus 700 in position over an electrical connector 800 for mounting thereto. The electrical connector 800 may comprise any connector having one or more rows of signal IDC slots. As shown, the electrical connector is substantially similar to that depicted in Figure 6, although it should be noted that many variations of such a connector are within the scope of the invention.

The electrical connector 800 has windows 801 which provide access to contact leads 803. Access to the contact leads is common in most plastic connectors which are formed using an overmolding process. That is, during the overmolding process, pins are used to hold contacts in place while plastic is injected around the contacts. Consequently, when the pins are removed after the plastic solidifies, an opening to the contacts is left. The present invention exploits this opening. The ground bus 700 and electrical connector 800 are configured such that the tabs 706 are insertable through windows 801 to contact leads 803. This way, the body section 701 becomes electrically connected to selected contact leads 803 by selective tabs 706.

Figure 9 shows the grounding system 800 in a fully seated position. As such the housing tabs 802 are snapped into cut-outs 705 to secure and align the ground bus 700 to the electrical connector 800.

Grounding to the various signal IDC slots is accomplished by the grounding tabs 706 contacting contact leads 803 (not shown) through windows 801 (not shown). As with the above embodiments of the grounding bus, grounding bus 700 may be configured by selectively removing tabs 706, thereby leaving a selection of tabs 706 which contact particular contact leads 803 thereby electrically connecting to the ground bus the respective signal IDC slots to which the particular contact leads are connected.

Variations and modifications may be made to the specific embodiment disclosed herein, that are within the spirit of the invention and the scope of the claims.

Claims

What is claimed is:

1. A ground bus for use with an electrical connector having a housing with one or more rows of signal IDC slots thereon, said ground bus comprising: a body section adapted for mounting to a housing of an electrical connector; one or more connectors for mounting said body section to said housing prior to connecting a conductor to said electrical connector; at least one grounding member extending from said body section to facilitate an electrical connection between a signal IDC slot on said housing and said ground bus.

2. The ground bus of claim 1, wherein said grounding member is a grounding IDC slot positioned on said body section such that, when said body section is mounted on said electrical connector, said grounding IDC slot aligns with said signal IDC slot such that a common conductor is insertable in both slots thereby electrically connecting the two.

3. The ground bus of claim 2, wherein said ground bus comprises a plurality of grounding IDC slots, at least one of which is frangibly connected to said body section.

4. The ground bus of claim 3, wherein said ground bus is formed of a stamped, conductive material wherein said body section and said grounding IDC slots are substantially planer prior to configuring said ground bus.

5. The ground bus of claim 3, wherein said body section is adapted to mount to a landing area of said housing, said landing area being distally disposed from the mating end of said electrical connector relative to said signal IDC slots.

6. The ground bus of claim 5, wherein said body section is substantially planer, said connectors extend substantially normal from said body section and have one or more recesses for receiving a latching projection on said housing, said grounding IDC slots extending normally from said body section in an opposite direction from said connectors.

7. The ground bus of claim 1, wherein said grounding member is a tab for operatively contacting said signal IDC slot when said ground bus is mounted to said housing.

8. The ground bus of claim 7, wherein said tab is frangible.

9. The ground bus of claim 8, wherein said body section has a planer section having orifices adapted to accommodate said signal IDC slots such that said signal IDC slots are not contacting said body section when said ground bus is mounted to said housing.

10. The ground bus of claim 9, wherein said tab directly contacts said signal IDC slot when said ground bus is mounted to said housing.

11. The ground bus of claim 10, wherein said tab extends from the edge of an orifice into said orifice such that it contacts said signal IDC contact when said ground bus is mounted to said housing.

12. The ground bus of claim 11 , wherein two opposing tabs extend from the edge of said orifice into said orifice such that they engage a beam of said signal IDC contact when said ground bus is mounted to said housing.

13. The ground bus of claim 9, wherein said tab extends from said body section such that, when said ground bus is mounted on said housing, said tab passes through a window in the housing that provides access a contact lead which is electrically connected to said signal IDC slot, and contacts said contact lead.

14. The ground bus of claim 1, wherein said body section is contoured to overlay at least a portion of said housing.

15. The ground bus of claim 14. wherein said body section is tiered to accommodate a tiered electrical connector.

16. The ground bus of claim 1, wherein said ground bus is releasably mountable to said housing.

17. An electrical connector comprising: a housing having one or more rows of signal IDC slots thereon; a ground bus comprising: a body section; one or more connectors for mounting said body section to said housing prior to the connection of a conductor to said electrical connector; at least one grounding member extending from said body section to facilitate an electrical connection between a signal IDC slot and said ground bus.

18. The electrical connector of claim 17, wherein said grounding member is a grounding IDC slot positioned on said body section such that said grounding IDC slot aligns with said signal IDC slot such that a common conductor is insertable in both slots thereby electrically connecting the two.

19. The electrical connector of claim 18, wherein said housing comprises a landing area disposed behind said signal IDC slots relative to the mating end of said electrical connector, said body section being adapted to mount to said landing area.

20. The electrical connector of claim 17, wherein said grounding member is a tab for operatively electrically connecting to said signal IDC slot.

21. The electrical connector of claim 20, wherein said body section has a planer portion having orifices adapted to accommodate said signal IDC slots such that said signal IDC slots are not contacting said body section.

22. The electrical connector of claim 21, wherein said tab extends from the edge of an orifice into said orifice such that it contacts said signal IDC contact.

23. The electrical connector of claim 21, wherein said housing has at least one window providing access to a contact lead therein which is electrically connected to said signal IDC slot, said tab extending from said body section such that it passes through said window and contacts said contact lead.

24. A method of terminating a conductor to a connector, said method comprising:

(a) providing an electrical connector having a housing with one or more rows of signal IDC slots and having mounted thereto a ground bus comprising: (i) a body section; (ii) one or more connectors for mounting said body section to said housing prior to connecting a conductor to said electrical connector; and (iii) at least one grounding member extending from said body section to facilitate an electrical connection between a signal IDC slot and said ground bus; and

(b) inserting a conductor into one or more of said signal IDC slots such that at least one signal IDC slot is electrically connected to said ground bus.

25. The method of claim 24, wherein step (b) is performed with an automated wire insertion apparatus.

26. The method of claim 24, wherein electrically connecting a signal IDC slot to said ground bus is effected by configuring said ground bus, wherein all grounding members are removed that correspond to signal IDC slots which are to remain electrically isolated from said ground bus.

27. The method of claim 24, wherein said grounding member is a grounding IDC slot positioned on said body section such that, when said body section is mounted on said electrical connector, said grounding IDC slot aligns with said signal IDC slot such that a common conductor is insertable in both slots thereby electrically connecting the two.

28. The method of claim 27, wherein electrically connecting a signal IDC slot to said ground bus is effected by either removing grounding IDC slots that align with signal IDC slots which are to remain electrically isolated from said ground bus, or altering the length of said conductors such that only those conductors that are to be grounded are long enough to engage both said grounding IDC slots and said signal IDC slots.

29. The method of claim 27, wherein, in step (b), a conductor is inserted into said signal IDC slot and said grounding IDC slot at the same time.