Abstract:
A shielded electrical connector provides continuous ground shielding about the connector. The connector includes a plurality of electrical contacts having contact tails. An insulative body insertably supports the contacts. A conductive housing having an open end is positioned over the insulative body, the contact tails extend outwardly of the conductive housing. An end shield is positioned adjacent the open end of the conductive housing. The end shield surrounds the contact tails providing shielding therebetween and is in interlocking engagement with the conductive housing thereby establishing electrical ground path continuity between the conductive housing and the end shield.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to shielded electrical data connectors. More particularly, the present invention relates to a compact data connector having improved electrical characteristics by providing a continuous ground shield about the connector which provides for external connector shielding and which additionally shields the contacts supported within the connector. 
     BACKGROUND OF THE INVENTION 
     Recent improvements in electrical data transmission, especially in the computer field, have resulted in the ability to transmit data along transmission lines at increasingly higher data rates. Further, similar improvements have also seen the decrease in the size of the equipment used in the industry. In order to function effectively with such equipment, the interconnection technology, such as the electrical cables and electrical connectors which connect such equipment, has also undergone significant improvements. Electrical connectors are now smaller and capable of transmitting data at higher rates between such components. 
     The requirement to make the electrical connectors smaller necessitates putting the conductive contacts of such connectors in closer proximity. However, when transmitting data at higher data rates, this physical proximity has a tendency to increase the cross-talk levels between adjacent electrical contacts supported in the connector. Such cross-talk may adversely effect the electrical performance of the connector. Thus, effective internal shielding must be provided as between selected contacts supported within the connector. 
     Similarly, these electrical connectors may be used in areas which may be subjected to externally induced interferences from other components, radio frequency interference (RFI) and electromagnetic interference (EMI) may also adversely effect connector performance. Accordingly, the industry has also seen the need for improving electrical shielding of the connectors so as to shield such connectors from these external interferences. 
     The need for effective shielding both internally and externally, is especially seen in connectors used in closed-loop data systems which provide for continuity of signal in a multi-component system when certain of the connectors are not interconnected. These closed-loop systems employ connectors containing devices which permit automatic shunting so that a closed-loop connection is maintained even when a connector is in a non-connected condition. The shunting devices used in these connectors render effective shielding even more problematic. 
     Further, as shielding is to be provided both internally and externally, ground continuity between the internal and external shielding is desirable. These connectors should provide a continuous ground path between the external and internal shields. 
     It is, therefore, desirable to provide an electrical connector which provides for continuous shielding in a compact connector design which shields selected contacts supported within the connector as well as shields the connector from outside interferences. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide an improved compact shielded electrical data connector. 
     It is a further object of the present invention to provide a shielded data connector which shields the connector from external interferences. 
     It is a still further object of the present invention to provide a shielded data connector which provides effective contact shielding so as to reduce cross-talk between selected contacts supported within the connector. 
     It is yet a further object of the present invention to provide reliable continuous ground path continuity between the internal and external shielding of an assembled electrical connector. 
     In the efficient attainment of these and other objects, the present invention provides a shielded electrical connector. The connector includes a plurality of electrical contacts, each of the contacts includes extending contact tails. An insulative body insertably accommodates and supports the contacts therein. A conductive housing having an open end is positioned over the insulative body and provides for external shielding of the connector. The contact tails are positioned to extend out from the open end of the conductive housing. An end shield is positioned adjacent the open end of the conductive housing. The end shield surrounds the contact tails providing shielding therebetween and is in interlocking engagement with the conductive housing for establishing electrical ground path continuity between the conductive housing and the end shield. 
     As more particularly described by way of the preferred embodiment herein, the conductive housing includes a pair of sidewalls supporting the insulative body therebetween. A slot is formed in each sidewall of the conductive housing. The end shield includes a pair of shield protrusions. Upon assembly of the end shield to the conductive housing the protrusions are insertable into the slots and are held therein in an interference relationship to mechanically and electrically connect the end shield to the conductive housing thereby providing a continuous ground path around the connector. The end shield also provides for the shielding of the contact tails so as to reduce cross-talk between contacts. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows in exploded bottom perspective view, the compact shielded data connector assembly of the present invention. 
     FIG. 2 is a rear, partially exploded perspective view of the connector assembly shown in FIG. 1. 
     FIG. 3 shows in vertical section, the connector assembly of FIG. 1. 
     FIG. 4 is a side elevational showing of the connector assembly of FIG. 3. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to the drawings, a shielded compact electrical data connector assembly 10 of the present invention is shown. Data connector assembly 10 is of the type used to transmit data signals between components of a closed loop data system. Connector assembly 10 may be constructed to function generally in a hermaphroditic fashion, that is, it is interconnectable to a similarly shaped electrical connector assembly. Alternately, it may function in a panel mount environment where plural such connector assemblies are supported on a wiring panel for connection with similarly formed electrical connectors. Connector assembly 10 of the present invention is of a type similar to that shown and described in U.S. patent application Ser. No. 08/092,049 filed on Jul. 14, 1993 and entitled &#34;Shielded Compact Data Connector&#34; which is assigned to the assignee of the present invention and which is incorporated by reference herein for all purposes. 
     Connector assembly 10 comprises an electrically conductive outer housing 12, an electrically insulative contact support member 14, upper and lower rows of electrical contacts 18 and 20 respectively, an insulative rear contact tail support 22 and a rear conductive shield 24. Conductive outer housing 12 and conductive rear shield 24 are formed, in the preferred embodiment, of a suitably conductive metal such as die-cast zinc, however, other conductive elements such as conductive plastic or metallized plastic, may also be employed. Support member 14 as well as rear contact tail support 22 are formed of a suitably electrically insulative plastic such as polyester. Electrical contacts 18 and 20 are formed of a suitably conductive metallic material such as beryllium-copper. 
     Outer housing 12 is generally an elongate rectangular member having a front interconnection end 26 and an open rear contact accommodating end 28. Outer housing 12 iS divided into discrete bounded compartments 30 internally thereof adjacent the interconnection end 26. Such compartments 30 are formed by a central vertical dividing wall 34 as well as a transverse dividing wall 32 (FIG. 3) which are preferably, but not necessarily integrally formed with outer housing 12. As described in the above incorporated patent application, the construction of outer housing 12 provides individual perimetrically bounded compartments 30 for accommodation of pairs of contacts 18 and 20 in an electrically shielded manner. 
     Contact support member 14 is generally an elongate molded plastic member having a generally open rear contact accommodating end 44, a central main body portion 46 and forwardly extending upper and lower support platforms 48 and 50 extending oppositely from rear contact accommodating end 44. Support member 14 includes a row of side-by-side upper channels 52 extending from rear contact accommodating end 44 through central main body portion 46 and along upper support platform 48. Similarly a row of side-by-side lower channels 54 extend from rear contact accommodating end 44 through central main body 46 and along lower support platform 50. Support member 14 is generally transversely divided into side-by-side portions 48a, 48b and 50a, 50b, by a passage 41 which extends partially through both support platforms 48 and 50. Passage 41 permits accommodation therein of central vertical dividing wall 34 of outer housing 12. Similarly, transverse wall 32 iS accommodated beneath the lower surface of upper support platform 48 (FIG. 3). In this manner each portion 48a, 48b and 50a, 50b of support platforms 48 and 50 is individually accommodated within one of bounded compartments 30. 
     Upper and lower electrical contacts 18 and 20 are typically stamped and formed metallic members. As shown in FIG. 3, lower contacts 20 include a generally elongate base portion 20a, a pin type solder tail 20b and a reversely directed cantilevered spring portion 20c which extends back over base portion 20a. Solder tail 20b is of conventional construction and may be inserted into a through-hole of a printed circuit board (not shown) and soldered thereto establishing electrical connection therebetween. In the present illustrative embodiment, solder tail 20b is shown extending downwardly at a right angle from base portion 20a. However, straight solder tails may also be employed in accordance with the present invention. Cantilevered spring portion 20c is constructed so as to be deflectable for movement toward and away from base portion 20a upon interconnection with contacts of a mating connection device. 
     Upper contacts 18 are of construction similar to that of contacts 20. Contacts 18 include an elongate base portion 18a, a solder tail 18b and a reversely directed cantilevered spring portion 18c. As contacts 18 and 20 are arranged in upper and lower fashion, solder tails 18b of contacts 18 are longer than solder tails 20b of contacts 20 so that the distal extents 18h and 20h of solder tails extend approximately the same distance, facilitating connection of the solder tails into a planar printed circuit board. As more fully described in the above-referenced incorporated patent application, each upper contact 18 may include a depending shunt member 18d which is engagable with a shunt engagement portion 20d of each contact 20. Thus, the upper contacts 18 may be shunted to lower contacts 20 so as to effectively function in a closed-loop environment. 
     Referring additionally again to FIG. 1, contacts 18 and 20 are supported by support member 14 within upper and lower channels 52 and 54 thereof. Base portions 18a and 20a are supported respectively on platforms 48 and 50 with a pair of contacts being supported on each of platform portions 48a, 48b and 50a, 50b. Solder tails 18b and 20b extend along rear contact accommodating end 44 of support member 14. Support member 14, supporting upper and lower contacts 18 and 20, is inserted into outer housing 12. As outer housing 12 is formed of an electrical conductive material it provides effective electrical shielding from external interferences. Further, the arrangement of portions 48a, 48b and 50a, 50b of the support platforms 4s and 50, provides for the support of adjacent pairs of contacts within individual compartments 30. In this manner, adjacent pairs of contacts are electrically shielded from one another effectively reducing cross-talk between contact pairs both vertically and horizontally within connector assembly 10. 
     The shielding of contacts 18 and 20 is continued at the contact accommodating end 28 of housing 12 by rear shield 24. As shown additionally in FIG. 2, shield 24 is formed of conductive metal and includes a short forward wall 56 and a taller rear wall 58 separated by a centrally located transverse web 60 (FIG. 1). The construction of shield 24 provides conductive shielding as between solder tails 18b of upper contacts and solder tails 20b of lower contacts. This is achieved by positioning solder tails 20b on one side of forward wall 56 while solder tails 18b are positioned on the other side of forward wall 56. Solder tails 18b reside between walls 56 and 58 (FIG. 3). 
     In order to provide electrical isolation between the contact tails, connector assembly 10 includes insulative contact tail support 22. Contact tail support 22 is a plastic member which is generally of rectangular shape and includes individual chambers 66 therein which accommodate solder tails 18b of contacts 18. Contact tail support 22 includes an upwardly opening recess 68 for accommodation of web 60 of shield 24 when contact 22 iS supported between walls 56 and 58. Contact support 22 may include a depending locating post 29 which, in conjunction with similarly formed locating posts 37 extending from conductive housing 12, help properly position and locate connector assembly 10 on the printed circuit board. Additional posts 39 may be used to provide keyed insertion of connector assembly 10 to the printed circuit board. 
     Rear shield 24 provides for electrical shielding between contact tails 18b and 20b extending from connector assembly 10. Together with the construction of the front interconnection end 26 of outer housing 12, effective continuous electrical shielding is provided between pairs of contacts 18 and 20 within connector assembly 10. In order to maintain conductive ground path continuity between outer housing 12, which also shields connector assembly 10 from external interferences, and rear shield 24 which provide shielding between contact tails, rear shield 24 iS mechanically and electrically secured to outer housing 12. 
     Outer housing 12 includes opposed sidewalls 12a and 12b which include transversely aligned open ended notches 70 extending from a lower edge 12c thereof. As more particularly shown in FIG. 4, notch 70 includes an open end 72 having a generally uniform transverse extent. Notch 70 then includes an inwardly tapered portion 74 terminating in a narrow notch portion 76 of uniform width. As shown in FIG. 2, short forward wall 56 of shield 24 includes outwardly projecting ear portions 80 extending adjacent a lower edge 56a thereof. Ear portions 80 have a generally rectangular cross section having slightly rounded upper corners 82 as shown in FIG. 4. The transverse extent of ear portions 80 is constructed to be equal to or slightly greater than the transverse extent of narrow portion 76 of notch 70. Notch 70 which is positioned on sidewalls 12a and 12b to accommodate extending ear portions 80 upon attachment of rear shield 24 to housing 12, accommodates each ear portion in frictional engagement. The wider open ends 72 of each notch 70 facilitate insertion of ear portions 80 thereinto. Tapered portion 74 leads ear portions 80 into narrow portion 76 where it is accommodated therein in an interference fit relationship. This frictional engagement provides tight metal-to-metal contact between housing 12 and shield 24. Thus, shield 24 is electrically commoned to housing 12 establishing ground path continuity therebetween. As connector housing 12 and shield 24 are formed of similar metals it is contemplated that the tight interference engagement therebetween will be maintained throughout use of the connector. Thus, the present invention provides shielding as between selected contacts supported therein along the entire extents thereof and also provides ground path continuity with conductive housing 12 shielding connector assembly 10 from external interferences. 
     Various changes to the foregoing described and shown structures would now be evident to those skilled in the art. Accordingly, the particularly disclosed scope of the invention is set forth in the following claims.