Eye-of-the needle pin of an electrical contact

An electrical contact includes a base and an eye-of-the needle (EON) pin extending a length outwardly from the base to a tip. The EON pin is configured to be received within an electrical via. The EON pin includes a neck segment that extends outwardly from the base, a tip segment that includes the tip, and a compliant segment that extends from the neck segment to the tip segment. The neck segment has opposite end walls and opposite side walls that extend between the end walls. The end walls are connected to the side walls at corresponding transitional walls that interconnect spaced-apart edges of the corresponding end and side walls.

BACKGROUND OF THE INVENTION

The subject matter described and/or illustrated herein relates generally to electrical contacts, and more particularly, to electrical contacts that include eye-of-the needle (EON) pins for mounting the electrical contact on a printed circuit.

In electronic systems that include printed circuits (sometimes referred to as “circuit boards” or “printed circuit boards”), the printed circuit is typically electrically connected to another electrical device, such as another printed circuit, an electrical cable, an electrical power source, and/or the like. The printed circuit may be electrically connected directly to the other electrical device or may be electrically connected to the other electrical device through an intervening electrical connector. Many printed circuits are electrically connected to other electrical devices using electrical contacts of the other electrical device or the intervening electrical connector that include EON pins that are received within electrical vias of the printed circuit. Specifically, the EON pins include compliant segments that deform as the EON pin is inserted into the electrical via. The compliant segment engages an electrically conductive material on the interior wall of the electrical via to establish an electrical connection between the electrical via and the EON pin.

As electronic systems become smaller, the signal paths thereof become more densely grouped. Moreover, the rate at which the electrical data signals propagate along the signal paths is continually increasing to satisfy the demand for faster electronic systems. There is a demand for reducing the size of the electrical vias within printed circuits to satisfy the increased density and/or higher signal rates. For example, smaller electrical vias can be more densely grouped on the printed circuit. Moreover, and for example, smaller electrical vias may have better electrical performance (e.g., less interference with neighboring electrical vias) than larger electrical vias, which may enable the smaller electrical vias to carry a higher signal rate.

As electrical vias within printed circuits are made smaller, the EON pins must also be reduced in size to fit into such smaller electrical vias. But, such smaller EON pins may not retain enough structural rigidity to resist buckling as the EON pin is inserted into the electrical via. For example, EON pins of electrical contacts include a neck segment that extends between, and interconnects, the compliant segment to a base of the electrical contact. In addition to the compliant segment, the neck segment is also reduced in size to fit into a smaller electrical via. The neck segment may become so small that the force required to insert the compliant segment into the electrical via exceeds the structural rigidity of the neck segment. Accordingly, the EON pin may buckle about the neck segment and thereby fold over the printed circuit instead of sliding into the electrical via, which may result in a poor or no electrical connection between the EON pin and the electrical via.

BRIEF DESCRIPTION OF THE INVENTION

In one embodiment, an electrical contact includes a base and an eye-of-the needle (EON) pin extending a length outwardly from the base to a tip. The EON pin is configured to be received within an electrical via. The EON pin includes a neck segment that extends outwardly from the base, a tip segment that includes the tip, and a compliant segment that extends from the neck segment to the tip segment. The neck segment has opposite end walls and opposite side walls that extend between the end walls. The end walls are connected to the side walls at corresponding transitional walls that interconnect spaced-apart edges of the corresponding end and side walls.

In another embodiment, an electrical contact includes a base and an eye-of-the needle (EON) pin extending a length outwardly from the base to a tip. The EON pin is configured to be received within an electrical via. The EON pin includes a neck segment that extends outwardly from the base, a tip segment that includes the tip, and a compliant segment that extends from the neck segment to the tip segment. The neck segment has opposite end walls and opposite side walls that extend between the end walls. The end walls are connected to the side walls at corresponding transitional walls that define corners between the corresponding end and side walls. The corners include at least one of a round, a fillet, or a chamfer.

In another embodiment, an electrical contact includes a base and an eye-of-the needle (EON) pin extending a length outwardly from the base to a tip. The EON pin is configured to be received within an electrical via. The EON pin includes a neck segment that extends outwardly from the base, a tip segment that includes the tip, and a compliant segment that extends from the neck segment to the tip segment. A cross section taken through the neck segment in a direction perpendicular to the length of the EON pin is non-rectangular.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1is a partially exploded perspective view of an exemplary embodiment of an electrical connector and printed circuit assembly10. The assembly10includes a printed circuit12and an electrical connector14. The electrical connector14is configured to be mounted on the printed circuit12such that the electrical connector14is electrically connected to the printed circuit12. The electrical connector14is used to electrically connect the printed circuit12to any other electrical device (not shown), such as, but not limited to, another printed circuit, an electrical cable, an electrical power source, and/or the like. In the exemplary embodiment, the electrical connector14mates with a complementary mating connector (not shown) mounted on the other electrical device to establish an electrical connection between the printed circuit12and the other electrical device. Alternatively, the electrical connector14mates directly with the other electrical device to electrically connect the printed circuit12to the other electrical device without the use of an intervening mating connector.

The electrical connector14includes a housing16that holds a plurality of electrical contacts18. The housing16includes a mating segment20and a mounting segment22. The mating segment20mates with the mating connector and includes a mating face24, while the mounting segment22includes a mounting face26. A plurality of ports28extend through the mating face24for exposing mating segments30of the electrical contacts18. In the exemplary embodiment, the mating segments30of the electrical contacts18mate with mating contacts (not shown) of the mating connector to electrically connect the electrical connector14to the mating connector. The mating segment20of the housing16optionally defines a plug that is configured to be received within a receptacle (not shown) of the mating connector. In the exemplary embodiment, the mating and mounting faces24and26, respectively, extend opposite, and thus approximately parallel, to each other. Alternatively, the mating and mounting faces24and26, respectively, extend at any other angle relative to each other, such as an approximately perpendicular angle or an oblique angle. The electrical connector14may include any number of the electrical contacts18.

FIG. 2is a perspective view of an exemplary embodiment of the electrical connector14.FIG. 2illustrates the mounting segment22and the mounting face26of the housing16. The mounting segment22is configured to be mounted on the printed circuit12(FIG. 1). Optionally, the mounting face26engages the printed circuit12when the electrical connector14is fully mounted on the printed circuit12. The electrical contacts18include eye-of-the needle (EON) pins32that extend outwardly along the mounting face26of the housing16. When the electrical connector14is mounted on the printed circuit12, the EON pins32are received within corresponding electrical vias34(FIGS. 1 and 6) of the printed circuit12to electrically connect the electrical contacts18to the printed circuit12.

The electrical contacts shown and/or described herein (e.g., the electrical contact18) are components of the electrical connector14. But, the electrical contacts shown and/or described herein may alternatively be components of the other electrical device that electrically connects to the printed circuit12. Moreover, the EON pins shown and/or described herein (e.g., the EON pins32,232, and332) are not limited to being used with the electrical connector14. Rather, the electrical connector14shown and described herein is meant as exemplary only. The EON pins shown and/or described herein may be used with any other type of electrical connector and may be used with electrical connectors having different geometries, configurations, and/or the like than the electrical connector14.

Referring again toFIG. 1, the printed circuit12includes a substrate48having a pair of opposite sides50and52. The electrical connector14mounts onto the side50of the substrate48. The printed circuit12includes the electrical vias34, which extend into the side50of the substrate48. The electrical vias34are defined by openings within the substrate48that have interior walls that include an electrically conductive material thereon, such that the electrical vias34are electrically conductive. The electrical vias34are optionally electrically connected to electrical circuits (not shown) of the printed circuit12, electrical components (not shown) of the printed circuit12, and/or the like. Each electrical via34receives the EON pin32(FIGS. 2-6) of a corresponding electrical contact18of the electrical connector14therein. The printed circuit12may include any number of the electrical vias34for receiving any number of EON pins32of the electrical connector14. Each electrical via34may extend completely through the substrate48or may extend into the side50only partially through the substrate48.

FIG. 3is a plan view of an exemplary embodiment of one of the electrical contacts18. The electrical contact18includes a base54, the mating segment30, and the EON pin32. The base54extends a length from an end56to an opposite end58. The EON pin32extends outwardly from the end56of the base54. The mating segment30extends outwardly from the end58of the base54. The base54includes optional retention features for securing the electrical contact18to the housing16(FIGS. 1 and 2) of the electrical connector14(FIGS. 1 and 2). In the exemplary embodiment, the retention features include retention barbs60that extend outwardly along sides of the base54and engage interior walls of the housing16to hold the base54within the housing16. Although eight are shown, the base54may include any number of the retention barbs60. Moreover, in addition or alternatively to the retention barbs60, the base54may include other types of retention features for holding the base54within the housing16.

The mating segment30extends outwardly from the base54to an end62. When the base54is held within the housing16, the mating segment30extends within the corresponding port28of the housing16for engagement with the corresponding mating contact of the mating connector. In the exemplary embodiment, the mating segment30includes a pair of resiliently deflectable fingers64that are spaced apart to define a mating slot66therebetween. The mating contact is inserted within the mating slot66of the mating segment30to mate the electrical contact18and the mating contact together. When the mating contact is received within the mating slot66, each finger64of the mating segment30engages the mating contact to establish an electrical connection between the electrical contact18and the mating contact. In addition or alternatively to the fingers64, the mating segment30may include any other geometry, configuration, and/or the like for mating with the mating contact. For example, in some alternative embodiments, the mating segment30includes a pin (not shown) that is received within a receptacle (not shown) of the mating contact.

The EON pins shown and/or described herein (e.g., the EON pins32,232, and332) are not limited to being used as a component of the electrical contacts18. Rather, the remainder (besides the EON pin32) of the electrical contact18shown and described herein is meant as exemplary only. The EON pins shown and/or described herein may be used as a component of any other type of electrical contact (whether such other type of electrical contact is a component of an electrical device or an intervening electrical connector) and may be used as a component of other electrical contacts having different base and mating segment geometries, configurations, and/or the like than the electrical contacts18.

FIG. 4is a perspective view of a portion of one of the electrical contacts18illustrating an exemplary embodiment of the EON pin32of the electrical contact18. The base54includes opposite side walls44and46that define a width W of the base54therebetween. The EON pin32extends a length outwardly from the base54to a tip68. The EON pin32includes a neck segment70, a compliant segment72, and a tip segment74. The neck segment70extends outwardly from the base54. The compliant segment72extends outwardly from the neck segment70, and the tip segment74extends outwardly from the compliant segment72. In other words, the compliant segment72extends from the neck segment70to the tip segment74. The tip segment74includes the tip68. The side walls44and46of the base54may each be referred to herein as a “base side wall”. The width W of the base54may be referred to herein as a “base width”.

The neck segment70includes a base sub-segment76and a via sub-segment78. The base sub-segment76extends outwardly from the base54. The via sub-segment78extends from the base sub-segment76to the compliant segment72. When the EON pin32is received within the corresponding electrical via34(FIGS. 1 and 6) of the printed circuit12(FIG. 1), the via sub-segment78extends within the electrical via34, while at least a portion of the base sub-segment76extends outside the electrical via34. In some embodiments, an entirety of the base sub-segment76extends outside the electrical via34. The compliant segment72includes two opposing arms80and82. The arms80and82are spaced apart to define an opening84therebetween. As the EON pin32is received within the corresponding electrical via34, the arms80and82engage the electrically conductive material on the inner wall of the electrical via34and are deflected inwardly toward each other. Engagement between the arms80and82of the compliant segment72and the electrically conductive material of the electrical via34electrically connects the EON pin32to the electrical via34.

FIG. 5is a cross-sectional view of the electrical contact18taken along line5-5ofFIG. 4. Referring now toFIGS. 4 and 5, the EON pin32includes a pair of end walls86aand86bthat extend opposite each other, and a pair of side walls88aand88bthat extend opposite each other. The side walls88aand88bextend between the end walls86aand86b. Each of the segments70,72, and74(segments72and74are not visible inFIG. 5) of the EON pin32includes, and is partially defined by, the end walls86aand86band the side walls88aand88b. As best seen inFIG. 5, at the via sub-segment78of the neck segment70, the end walls86aand86bare spaced apart by a distance that defines a thickness T1of the via sub-segment78. As is also best seen inFIG. 5, the side walls88aand88bare spaced apart by a distance at the via sub-segment78that defines a width W1of the via sub-segment78. As should be apparent fromFIG. 4, the width W1of the via sub-segment78of the neck segment70is less than the width W of the base54.

In the exemplary embodiment, the end walls86aand86bextend approximately parallel to each other, but the end walls86aand86bmay alternatively extend at an oblique angle relative to each other. The side walls88aand88balso extend approximately parallel to each other in the exemplary embodiment. Alternatively, the side walls88aand88bextend at an oblique angle relative to each other. Although the end walls86aand86bextend approximately perpendicular to the side walls88aand88bin the exemplary embodiment, alternatively the end walls86aand/or86bextends at an oblique angle relative to the side walls88aand/or88b. Each of the side walls88aand88bmay be referred to herein as a “neck side wall”.

At the neck segment70, and more particularly at the via sub-segment78, each end wall86aand86bis connected to each side wall88aand88bat a corresponding transitional wall90,92,94, or96(wall92is not visible inFIG. 4). Specifically, and referring now solely toFIG. 5, each end wall86aand86bextends from a respective edge98aand98bto an opposite edge100aand100b, respectively. Similarly, each side wall88aand88bextends from an edge102aand102b, respectively, to an opposite edge104aand104b, respectively. As can be seen inFIG. 5, the edge100aof the end wall86ais spaced apart from the edge102aof the side wall88a, and the edge104aof the side wall88ais spaced apart from the edge98bof the end wall86b. The edge100bof the end wall86bis spaced apart from the edge102bof the side wall88b, and the edge104bof the side wall88bis spaced apart from the edge98aof the end wall86a. Each transitional wall90,92,94, and96interconnects the spaced-apart edges of the corresponding end and side walls86and88. More particularly, the transitional wall90corresponds to the end and side walls86aand88a, respectively. The transitional wall90extends from the edge100aof the end wall86ato the edge102aof the side wall88ato interconnect the corresponding end and side walls86aand88a, respectively. The transitional wall90defines a corner106between the end wall86aand the side wall88a.

The transitional wall92corresponds to the side wall88aand the end wall86band extends from the edge104aof the side wall88ato the edge98bof the end wall86bto interconnect the corresponding side and end walls88aand86b, respectively. The transitional wall92defines a corner108between the side wall88aand the end wall86b. The transitional wall94defines a corner110between the end wall86band the side wall88band extends from the edge100bof the end wall86bto the edge102bof the side wall88bto interconnect the corresponding end and side walls86band88b, respectively. The transitional wall96extends from the edge104bof the side wall88bto the edge98aof the end wall86ato interconnect the corresponding side and end walls88band86a, respectively. The transitional wall96defines a corner112between the side wall88band the end wall86a. Each of the transitional walls90,92,94, and96may be referred to herein as a “neck transitional wall”.

In the exemplary embodiment, each of the transitional walls90,92,94, and96is curved such that each of the corners106,108,110, and112includes a round. The rounded corners106,108,110, and112enable the via sub-segment78of the neck segment70to have a greater width W1and/or thickness T1for a given diameter of the corresponding electrical via34. In other words, even with a greater width W1and/or thickness T1, the via sub-segment78of the EON pin32will fit within the same diameter electrical via as an EON pin wherein the side and end walls of the via sub-segment intersect at pointed edges. The increased width W1and/or thickness T1of the via sub-segment78increases a structural rigidity of the neck segment70, which may enable the EON pin32to be received within the corresponding electrical via34without buckling at the neck segment70.

FIG. 6is a cross sectional view comparing the EON pin32to an EON pin114wherein end and side walls116and118, respectively, of a via sub-segment120thereof intersect at pointed edges.FIG. 6illustrates the via sub-segment78of the EON pin32received within the corresponding electrical via34. The via sub-segment120of the EON pin114is also shown inFIG. 6received within one of the electrical vias34.FIG. 6therefore illustrates the via sub-segments78and120as being received within electrical vias34that have the same diameter. Although the electrical vias34may have any diameter, one example of a diameter of the electrical vias34shown inFIG. 6is approximately 0.205 mm. Another example of a diameter of the electrical vias34is approximately 0.283 mm. At the via sub-segment120of the EON pin114, the end walls116are spaced apart by a distance that defines a thickness T2of the via sub-segment120. The side walls118are spaced apart by a distance at the via sub-segment120that defines a width W2of the via sub-segment120.

As can be seen inFIG. 6, the thicknesses T1and T2of the via sub-segments78and120, respectively, are approximately equal. Although the thicknesses T1and T2may have any value depending on the diameter of the electrical via34, one example of the thicknesses T1and T2is approximately 0.15 mm for an electrical via34having a diameter of approximately 0.205 mm. As can also be seen inFIG. 6, the width W1of the via sub-segment78is greater than the width W2of the via sub-segment120. Accordingly, the via sub-segment78has a greater width W1than the width W2of the via sub-segment120yet the via sub-segment78fits within the same diameter electrical via34as the via sub-segment120. Although the widths W1and W2may have any value depending on the diameter of the electrical via34, one example of the widths W1and W2is approximately 0.18 mm and approximately 0.13 mm, respectively, for an electrical via34having a diameter of approximately 0.205 mm. Accordingly, for an electrical via34having a diameter of approximately 0.205 mm, the via sub-segment78may have a width W1that is greater than the width W2of the via sub-segment120by 0.05 mm or approximately 38%.

The greater width W1of the via sub-segment78than the width W2of the via sub-segment120provides the via sub-segment78with an increased structural rigidity as compared to the via sub-segment120. The greater structural rigidity of the via sub-segment78may enable the EON pin32to be received within the corresponding electrical via34without buckling at the neck segment70. For example, the structural rigidity of the via sub-segment78may exceed the force required to insert the compliant segment72(FIG. 4) of the EON pin32into the corresponding electrical via34.

As discussed above, the transitional walls90,92,94, and96of the via sub-segment78enable the thickness T1and/or the width W1of the via sub-segment78to be greater than the thickness T2and/or the width W2of the via sub-segment120for a given diameter electrical via34. In the exemplary embodiment, only the width W1of the via sub-segment78has been increased (relative to the via sub-segment120of the EON pin114). But, alternatively the thickness T1or both the width W1and the thickness T1of the via sub-segment78are increased relative to the via sub-segment120of the EON pin114.

The rounded corners106,108,110, and112may each have a round of any radius for enabling the thickness T1and/or the width W1to be increased for a given diameter electrical via34. A greater radius may enable a greater increase in the thickness T1and/or the width W1. In the exemplary embodiment, the rounded corners106,108,110, and112are each provided with a round having a radius of approximately 0.05 mm. But, the 0.05 mm radius rounds are meant as exemplary only. Each corner106,108,110, and112may have a round having any radius for providing any amount of increased thickness T1and/or width W1.

The transitional walls90,92,94, and96are not limited to being convexly curved to define the rounded corners106,108,110, and112. Rather, each corner106,108,110, and112may alternatively have a chamfer, a fillet, or a combination of a round, chamfer, and/or fillet. Moreover, in some alternative embodiments, at least one of the corners106,108,110, and/or112of the same via sub-segment78has a differently shaped transitional wall90,92,94, and/or96than at least one other corner106,108,110, and/or112of the via sub-segment78. For example, one of the corners106,108,110, or112may include a round while another of the corners106,108,110, or112includes a chamfer, a fillet, or a combination of a round, chamfer, and/or fillet.

FIG. 7is a cross-sectional view of an exemplary alternative embodiment of a via sub-segment278of a neck segment270of an EON pin232illustrating chamfered corners. The EON pin232includes end walls286that are spaced apart by a distance that defines a thickness T3of the via sub-segment278, and side walls288that are spaced apart by a distance that defines a width W3of the via sub-segment278. Each end wall286is connected to each side wall288at a corresponding transitional wall290,292,294, or296. The transitional walls290,292,294, and296define respective corners306,308,310, and312between the end walls286and the side walls288. Each of the transitional walls290,292,294, and296is approximately planar and is angled obliquely to the end walls286and the side walls288such that each of the corners306,308,310, and312includes a chamfer. The chamfered corners306,308,310, and312enable the via sub-segment278to have a greater width W3and/or thickness T3than the via sub-segment120(FIG. 6) of the EON pin114(FIG. 6) yet still fit within the same diameter electrical via34. The increased width W3and/or thickness T3of the via sub-segment278increases a structural rigidity of the neck segment270, which may enable the EON pin232to be received within the corresponding electrical via34without buckling at the neck segment270. In the exemplary embodiment ofFIG. 7, the thickness T3has been increased relative to the thickness T2(FIG. 6) of the via sub-segment120of the EON pin114.

FIG. 8is a cross-sectional view of an exemplary alternative embodiment of a via sub-segment378of a neck segment370of an EON pin332illustrating filleted corners. The EON pin332includes end walls386that are spaced apart by a distance that defines a thickness T4of the via sub-segment378, and side walls388that are spaced apart by a distance that defines a width W4of the via sub-segment378. Each end wall386is connected to each side wall388at a corresponding transitional wall390,392,394, or396. The transitional walls390,392,394, and396define respective corners406,408,410, and412between the end walls386and the side walls388. Each of the transitional walls390,392,394, and396is curved and includes a concave shape such that each of the corners406,408,410, and412includes a fillet. The filleted corners406.408,410, and412enable the via sub-segment378to have a greater width W4and/or thickness T4than the via sub-segment120(FIG. 6) of the EON pin114(FIG. 6) yet still fit within the same diameter electrical via34. The increased width W4and/or thickness T4of the via sub-segment378increases a structural rigidity of the neck segment370, which may enable the EON pin332to be received within the corresponding electrical via34without buckling at the neck segment370. In the exemplary embodiment ofFIG. 8, both the width W4and the thickness T4have been increased relative to the width W2(FIG. 6) and thickness T2(FIG. 6) of the via sub-segment120of the EON pin114.

Referring again toFIG. 4, in the exemplary embodiment, the compliant segment72and the tip segment74both include the transitional walls90,92,94, and96(the wall92is not visible inFIG. 4). Accordingly, both the compliant segment72and the tip segment74include the rounded corners106,108,110, and112(the corner108is not visible inFIG. 4). Alternatively, the compliant segment72and/or the tip segment74do not include the transitional walls90,92,94, and96and therefore do not include the corners106,108,110, and112. Rather, in such alternative embodiments, the end walls86and the side walls88intersect at pointed edges along the compliant segment72and/or the tip segment74. Moreover, the compliant segment72and the tip segment74are not limited to the rounded corners106,108,110, and112. Rather, both the compliant segment72and the tip segment74may include corners106,108,110, and112that have a chamfer, a fillet, or a combination of a round, chamfer, and/or fillet.

As used herein, the term “printed circuit” is intended to mean any electric circuit in which the conducting connections have been printed or otherwise deposited in predetermined patterns on an electrically insulating substrate. The substrate48of the printed circuit12may be a flexible substrate or a rigid substrate. The substrate48may be fabricated from and/or include any material(s), such as, but not limited to, ceramic, epoxy-glass, polyimide (such as, but not limited to, Kapton® and/or the like), organic material, plastic, polymer, and/or the like. In some embodiments, the substrate48is a rigid substrate fabricated from epoxy-glass, such that the printed circuit12is what is sometimes referred to as a “circuit board” or a “printed circuit board”.