Electrical connector with grounding system

Abstract: An electrical connector (10) comprising a housing (12) and electrical contacts (32, 34) connected to the housing (12). The electrical contacts (32, 34) comprise paired signal and ground contacts, and additional ground contacts (34a). The additional ground contacts (34a) are arranged relative to the paired contacts to divide the paired contacts into subdivisions of equal numbers of the paired contacts. The subdivisions and the additional ground contacts (34a) are arranged to allow for multiple relative orientation connections of a mating connector (100).

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electrical connectors and, more particularly, to an electrical connector as described in the preamble portion of patent claim 1. Such an electrical connector is known from US-A-5 904 594. 2. Brief Description of Earlier Developments U.S. Patents 5,429,520 and 5,433,617 disclose electrical connectors having a ground contact plate unit with a general cross shape and a cross-shaped receiving area in a mating electrical connector establishing four quadrants of contacts. It is also known in the connector art for two contacts in an electrical connector to transmit the same signal (but in opposite voltage), such as for high speed signals, wherein the differences between the parallel signals can be compaired or combined with any differences (e.g. noise) being removed. These are generally known as a "differential pair" of contacts. A "single ended" contact generally refers to a single signal contact surrounded by a ground (e.g. a coaxial conductor or pseudo-coaxial arrangement). It is desired to provide electrical connectors with contacts arranged in a symmetrical mating pattern which allows a first connector to be mated with a second connector in various orientations, such as 90° apart. A problem exists with conventional electrical connectors in that they do not allow common electrical connector parts to be used in the manufacture of both an electrical connector with only single ended signal contacts and an electrical connector with both differential pair contacts and single ended contacts. It is also desired to provide differential pair and single ended contact arrangements which can use common manufacturing parts as used to manufacture the electrical connectors having only single ended contacts. A problem exists with conventional electrical connectors in that they do not allow differential pair and single ended contact arrangements to be configurable into different patterns. It is also desired to allow differential pair and single ended contact arrangements to be configurable into different patterns. US-5 904 594 discloses an electrical connector comprising a housing and electrical contacts connected to the housing and ground contacts. WO-A-9926321 shows a shielded electrical connector with a grounded shield meandering around a plurality of signal contacts. SUMMARY OF THE INVENTION In accordance with one embodiment of the present invention, an electrical connector is provided comprising a housing and electrical contacts connected to the housing. The electrical contacts comprise paired signal and ground contacts, and additional ground contacts. The additional ground contacts are arranged relative to the paired contacts to divide the paired contacts into subdivisions of equal numbers of the paired contacts. The subdivisions and the additional ground contacts are arranged to allow for multiple relative orientation connections of a mating connector. The subdivisions comprise four quadrants. In accordance with another embodiment of the present invention, an electrical connector is provided comprising subassembly wafers and a ground plane member. At least two of the wafers comprise a housing, paired signal and ground contacts, and an additional ground contact in a general center of a connection area for the paired contacts. The ground plane member is located between at least two of the wafers. The ground plane member has contact areas located between at least some of the paired contacts of one of the at least two wafers and at least some of the paired contacts of the other one of the at least two wafers. BRIEF DESCRIPTION OF THE DRAWINGS The foregoing aspects and other features of the present invention are explained in the following description, taken in connection with the accompanying drawings, wherein: Figure 1 is a perspective view of an electrical connector incorporating features of the present invention; Figure 1A is a perspective view of a portion of the connector shown in Figure 1; Figure 2 is an exploded perspective view of one of the contact module assemblies shown in Figure 1; Figure 3 is a front elevational view of the connector shown in Figure 1 with the front housing part and certain signal contacts removed; Figure 4 is a front elevational view of a mating electrical connector for use with the connector shown in Figure 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to Fig. 1, there is shown a perspective view of an electrical connector 10 incorporating features of the present invention. Although the present invention will be described with reference to the embodiments shown in the drawings, it should be understood that the present invention can be embodied in many alternate forms of embodiments. In addition, any suitable size, shape or type of elements or materials could be used. The connector 10 in this embodiment is a receptacle electrical connector adapted to be connected to a first electrical component (not shown) such as a printed circuit board and removably connectable to a mating electrical connector, such as a pin header (see Figure 4). The connector 10 and connection system is similar to that described in U.S. provisional patent application No.: 60/117,957 filed January 28, 1999 which is hereby incorporated by reference in its entirety. The connector 10 generally comprises a housing 12 and modules or subassembly wafers 14. However, in alternate embodiments more or less components can be provided. The housing 12 generally comprises a rear housing member 16 and a front housing member 18. Referring also to Figure 1A, rear housing member 16 is generally an open structure formed by sidewalls 35, 37; a rear wall 39; and a top wall 41. The open interior of rear housing member 16 receives the rear portions of a series of the modules 14 arranged side-by-side. Specifically a groove 71b receives a spline 71a to ensure proper alignment. Receptacle 10 accurately rests on a daughterboard (not shown) using alignment posts 43 extending downwardly from sidewalls 35, 37. Alignment posts 43 engage corresponding through holes in the daughterboard preferably by an interference fit. Front housing member 18 is also generally an open structure formed by a mating face 45; sidewalls 47, 49; bottom wall 51; and top wall 53. The open interior of the front housing member 18 receives the front portions of the series of modules 14 arranged side-by-side. As with housing 16, housing 18 can have grooves (not shown) to receive another spline 71a on wafer 30. Front housing member 18 secures to rear housing member 16 using latch structures 55, 57 on each housing, respectively. The front housing member 18 secures to the rear housing member 16 after placement of the modules 14 within the rear housing member 16. Once assembled, receptacle 10 can mount to the daughterboard. The mating face 45 of the front housing member 18 includes an array of lead-ins 59. Lead-ins 59 accept corresponding signal pins and ground pins from the header (See Figure 4). Once the header mates with the receptacle 10, the signal and ground contacts of receptacle 10 engage the signal pins and ground pins of the header. This feature will be described in more detail below. As seen in Figure 1A, the connector 10 can include a ground plane member 20. The ground plane member 20 is a one-piece member comprised of electrically conductive material which is also ferromagnetic. In alternate embodiments the ground plane member 20 could be comprised of multiple members. In this embodiment the ground plane member 20 comprises first connection ends 22 and second connection ends 24. The first connection ends 22 comprise through-hole solder trails, but any suitable second connection ends could be provided. The second connection ends 24 comprise opposing spring contact arms forming a pin receiving area therebetween, but any suitable second connection ends could be provided. The ground plane member 20 has break-off sections 26 between the second connection ends 24 and the main body 28. The break-off sections can be severed or cut during manufacturing to remove one or more of the second connection ends 24 to customize or configure the ground place member as further understood below. However, in an alternate embodiment the break-off section needs not be provided or any suitable type of severing system could be provided. Referring also to Figure 2 an exploded perspective view of one of the modules 14 is shown. Each module 14 generally comprises a frame or wafer 30, signal contacts 32 and ground contacts 34. However, in, alternate embodiments, more components could be provided, and/or the component need not be provided as uniform modules. Wafer 30 can be a block of insulative material. The wafer 30 can be formed from several pieces 30a, 30b. Alternatively, however, wafer 30 could be formed unitarily from one piece (not shown). In this embodiment the module 14 comprises six signal contacts and seven ground contacts, but any suitable number of contacts could be provided. The center ground contact 34a may also be omitted as further understood below. A first major surface 67 of wafer piece 30a has a series of channels, grooves or apertures 68 in which ground contacts 34 reside. When arranging modules 14 side-by-side, first major surface 67 of a first module 14 can abut a second major surface 69 of a second adjacent module. In order to place modules 14 side-by-side, second major surface 69 can be generally featureless. The top surface of wafer piece 30a includes a projection 71. As seen in Figure 1, projections 71 can abut the front edge of rear housing member 16 during, and after, assembly. The interaction between projections 71 and the front edge of rear housing member 16 helps align modules 14 within rear housing member 16. The wafer piece 30a can also have a spine 71a. The spine 71a can be located in a groove 71b in the rear housing piece 16. Signal contacts 32 include a mounting end 73 for securing to the daughterboard, a mating end 75 for interacting with signal pins of the header, and an intermediate portion 77. The mounting ends 73 can have press-fit solder tails that engage plated through holes in the daughterboard. However, other types of terminations for mounting ends 73 could be used. Typically, an overmolding process embeds signal contact 32 in wafer piece 30a (or wafer 30 if one piece), however, other techniques could be used. The second wafer piece 30b is preferably premolded and subsequently mounted over the mating ends 75 of the signal contacts 32. The second wafer piece 30b includes first receiving apertures 40 and second receiving apertures 42. The first receiving apertures 40 receive the mating ends 75 of the signal contacts 32. The second receiving apertures 42 receive the mating ends of the ground contacts 34. The center second receiving aperture 42a extends into an opposite side of the second wafer piece 30b than the other second receiving apertures 42, but this need not be provided. Also in this embodiment, the receiving apertures 40, 42 above the center second receiving aperture 42a are preferably mirror images of the receiving apertures 40, 42 below the center second receiving aperture 42a. However, this need not be provided. The mating end of the signal contacts 32 can have a dual beam contact configuration to engage signal pins of the header. The beams 79, 81 of the dual beam contact are arranged generally perpendicular to each other. In this arrangement, the bifurcation engages adjacent surfaces of the mating signal pins. Beams 79, 81 deflect upon insertion of the mating signal pins. The movement of signal pins along the beams 79, 81 during insertion provides good wiping action. In addition, the force imparted to the signal pins by deflection of the beams 79, 81 provides good contact pressure or contact normal force. As with signal contacts 32 the ground contacts 34 include a mounting end 83 for securing to the daughterboard, a mating end 85 for interacting with ground pins of the mating header, and an intermediate portion 87. Mounting ends 83 can have press-fit solder tails that engage plated through holes in the daughterboard. However, other types of terminations for mounting ends 83 could be used. Mating end 85 uses a dual beam-type contact arrangement to engage ground pins of the header. Mating end 85 includes a first beam 89 arranged generally perpendicular to a second beam 91. A minor surface of first beam 89 supports the ground pin. As discussed above, the beam 89 provides good contact force and wipe. Second beam 91 is bifurcated into a stationary section 93 and movable section 95. Upon engagement of movable section 95 of second beam 91 with a ground pin, movable section 95 deflects. As with the other contacts, the deflection provides good contact force and wipe. Signal contacts 32 within module 14, as with ground contacts 34 within module 14, preferably do not maintain the same orientation throughout the module 14. Furthermore, signal contacts 32 and ground contacts 34 in one module 14 preferably do not exhibit the same orientation as signal contacts 32 and ground contacts 34 in all of the other modules 14. Referring also to Figure 3, a front elevational view of the connector 10 is shown with the front housing member 18 removed. In this embodiment the connector 10 comprises six of the modules 14. In alternate embodiments more or less than six modules could be used. In this embodiment the six modules 14 actually comprise two types of modules 14a, 14b which are mirror images of each other. In alternate embodiments more or less than two types of modules could be provided and, the modules need not be mirror images of each other. The general L shape of the signal contacts 32 generally correspond to the positions of the beams 79, 81. Likewise, the general L shape of the ground contacts 34 generally correspond to the positions of the beams 89, 91. Two areas L1, L2, preferably passing through a center of the receptacle 10, define four quadrants Q1, Q2, Q3, Q4. Each signal contact 32 corresponds to a ground contact 34 to form a contact pair. In the arrangement shown in Figure 3, the signal contact 32 and ground contact 34 in each contact pair have the same orientation. In other words, signal contact 32 and ground contact 34 of contact pair face the same direction. Generally speaking, the orientation of each contact pair within a quadrant (even in a different module) remains the same. However, the orientation of contact pairs in other quadrants differ from the orientation of contact pairs in other quadrants (even on the same module). Typically, contact pairs in one quadrant are rotated 90° relative to contact pairs in an adjacent quadrant. For example, a contact pair in quadrant Q1 is rotated 90° relative to a contact pair in quadrant Q2. Since one module 14 can have contacts 32, 34 residing in more than one quadrant, the orientation of some contacts 32, 34 in each module 14 can differ from the orientation of other contacts in the same module. Typically, contact pairs in a module 14 that reside in one quadrant are preferably mirror images of the contact pairs in the same module that reside in the other quadrant. For example, module 14a in Figure 3 has contact pairs in quadrants Q1 and Q4. Contact pairs in module 14a that are in quadrant Q1 are mirror images of the contact pairs in quadrant Q4. Other arrangements are also possible. In an appropriate situation, the contact in one quadrant could be rotated 90° to the contacts in the adjacent quadrant. Area L1 is generally occupied by the ground plane member 20 for single ended applications. Thus, the ground plane member 20 forms a ground and a shield through the center of the connector 10 between the signal contacts 32 in the two modules 14a, 14b closest to the ground plane member. For example, the top second connection end 24a is located between the mating ends 75a, 75a of the two top signal contacts 32 on opposite sides of the ground plane member. Area L2 is generally occupied by the module ground contacts 34a for single ended applications. Thus, the module ground contacts 34a form both grounds and shields in a path generally through the center of the connector 10 between the signal contacts in each respective module 14 closest to the module ground contact 34a. For example, the mating ends 75b, 75b of the two middle signal contacts 32 on opposite sides of each module ground contact 34a and their intermediate portions 77 (see Fig. 2 will have the module ground contacts 34a therebetween. With this arrangement the ground contacts 34a and ground plane member 20 form a general cross-shaped ground and shield between the four quadrants Q1, Q2, Q3, Q4, but which still allows for 90° offset connection possibilities with the mating electrical connector pin header. Ground plane 20, ground contacts 34a and ground contacts 34 form a pseudo-coaxial structure around each signal contact 32. Clearly, therefore, the signal contacts 32 are preferably single ended signal contacts. Figure 4 is a front elevational view of a mating electrical connector or header 100 adapted to be connected to the receptacle connector 10. In particular, the connector 100 is a pin header connector which is fixedly connectable to an electrical component, such as a printed circuit board. The connector 100 includes a housing 102, ground contacts 104, associated signal contacts 106, and ground shields 108. The housing 102 includes a receiving area 110 for receiving the mating face 45 of the receptacle connector 10. The ground contacts 104 have male pin sections 112. The signal contacts 106 have male pin sections 114. When the two connectors 10, 100 are properly connected to each other, the pin section 112, 114 extend into the lead-ins 59 and make electrical contact with the ground contacts 34 and signal contacts 32, respectively. The mating connector 100 may also comprise additional ground contacts 104a. The additional ground contacts 104a do not have associated or paired respective signal contacts as the other ground contacts 104 but help create a pseudo-coaxial structure. In this embodiment the additional ground contacts 104a are arranged in a general cross-shaped pattern as illustrated by area L3. The male pin sections of the additional ground contacts 104a are adapted to make electrical contact with the ground contacts 34a in area L2 and ground plane member 20 in area L1 shown in Figure 3. It should be understood that the foregoing description is only illustrative of the invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims.

Claims: An electrical connector (10) comprising: a housing (12); and electrical contacts connected to the housing (12), the electrical contacts comprising signal and ground contacts (32, 34), characterized in that said signal and ground contacts are paired contacts (32, 34) and additional ground contacts (34a; 20) are arranged relative to the paired contacts (32, 34) to divide the paired contacts (32, 34) into subdivisions of equal numbers of the paired contacts (32, 34), wherein the subdivisions comprise four quadrants (Q1-Q4). An electrical connector (10) as in Claim 1, characterized in that the additional ground contacts (34a; 20) form a general cross shape. An electrical connector (10) as in Claim 1, characterized in that a portion of the housing (12), the paired contacts (32, 34), and some of the additional ground contacts (34a; 20) are formed as subassembly wafers (14) which are subsequently sandwiched together to form the electrical connector (10). An electrical connector (10) as in Claim 3, characterized in that the additional ground contacts (34a) include at least one of the additional ground contacts (20) being sandwiched between two of the subassembly wafers (14). An electrical connector (10) as in Claim 1, characterized in that the additional ground contacts (34a; 20) comprise a row (L2) of horizontally centered and a column (L1) of vertically centered connection areas at a mating connector connection area. An electrical connector (10) as in Claim 1, characterized in that the subdivisions and the additional ground contacts (34a; 20) are arranged to allow for multiple relative orientation connections of a mating connector. An electrical connector (10) as in Claim 3, characterized in that at least two of the wafers (14) comprising a housing (12), paired signal and ground contacts (32, 34), and an additional ground contact (34a) in a general center of a connection area for the paired contacts (32, 34); and a ground plane member (20) is located between at least two of the wafers (14), the ground plane member (20) having contact areas (24) located between at least some of the paired contacts (32, 34) of one of the at least two wafers (14) and at least some of the paired contacts (32, 34) of the other one of the at least two wafers (14). An electrical connector (10) as in Claim 7, characterized in that the at least two wafers (14) each have equal numbers of paired contacts (32, 34) on opposite sides of their respective additional ground contact (34a; 20). An electrical connector (10) as in Claim 7, characterized in that the ground plane member (20) has contact areas (24) located between all the paired contacts (32, 34) of the one wafer (14) and the other wafer (14). An electrical connector (10) as in Claim 7, characterized in that the additional ground contacts (34a) and the ground plane member (20) form a general cross shape at the connection area. An electrical connector (10) as in Claim 10, characterized in that the general cross shape divides the paired contacts into four quadrants (Q1 - Q4) of equal numbers of the paired contacts (32, 34).

Inventors: BILLMAN TIMOTHY B, WEAVER JOHN H JR, BILLMAN, TIMOTHY B., WEAVER, JOHN H., JR.
Applicants: FRAMATOME CONNECTORS INT, FCI
Application year: 2001
Main classification: H01R12
IPC codes: H01R13, H01R43