Patent Grant
9666966
The subject matter herein relates generally to electrical connectors having electrical contacts that engage corresponding mating contacts during a mating operation with another electrical connector.
Electrical connectors are used to transmit data and/or power in various industries. The electrical connectors are often configured to repeatedly engage and disengage complementary electrical connectors. The process of mating the electrical connectors may be referred to as a mating operation. Each mating operation may cause a small amount of wear to the electrical connectors. For example, in a backplane communication system, a backplane circuit board has a header connector that is configured to mate with a receptacle connector. The receptacle connector is typically mounted to a daughter card. The header connector includes an array of electrical contacts (hereinafter referred to as “header contacts”), and the receptacle connector includes a complementary array of electrical contacts (hereinafter referred to as “receptacle contacts”). During the mating operation, the receptacle contacts mechanically engage and slide along the corresponding header contacts. The sliding engagement between the receptacle and header contacts may be referred to as wiping, because each receptacle contact wipes along an exterior surface of the corresponding header contact. At this time, adhesion between the receptacle contact and the corresponding header contact may remove surface materials from the corresponding header contact as the receptacle contact wipes the header contact.
In many cases, the header contacts are disposed within a connector cavity of the header connector that is sized and shaped to receive the receptacle connector. The connector cavity opens to an exterior of the header connector thereby exposing the header contacts to an ambient environment. Certain environmental conditions in the ambient environment, such as humidity, may increase the likelihood of corrosion developing on the exterior surfaces of the header contacts. The portions of the header contacts that are closest to the cavity opening are more exposed to the ambient environment and may be at greater risk for developing corrosion.
Corrosion can negatively affect performance of an electrical connector. For example, each of the receptacle contacts is configured to engage the corresponding header contact at a final contact area when the receptacle and header connectors are fully mated and in operation. However, as the receptacle contact wipes the header contact during the mating operation, the receptacle contact may push or plow the corrosive matter toward the final contact area. Corrosive matter at the final contact area may cause an unstable electrical connection between the receptacle contact and the header contact, which can negatively affect signal transmission through the mated connectors.
Accordingly, a need remains for electrical contacts and electrical connectors that reduce an amount of corrosive matter at the final contact area.
In an embodiment, an electrical connector is provided that includes a connector housing configured to engage a mating connector during a mating operation. The electrical connector also includes a contact array having electrical contacts that are coupled to the connector housing. Each of the electrical contacts includes a proximal base coupled to the connector housing and an elongated body that extends from the proximal base to a distal end. The elongated body has a longitudinal axis extending between the proximal base and the distal end, and a lateral axis that is perpendicular to the longitudinal axis. The elongated body includes a body side that extends along the longitudinal and lateral axes and is shaped to form a wipe track. The wipe track is configured to engage a contact finger of the mating connector as the contact finger moves linearly along the longitudinal axis. The wipe track has a non-linear path such that the wipe track turns at least partially in a lateral direction as the wipe track moves toward the proximal base along the longitudinal axis.
In an embodiment, an electrical connector is provided that includes a connector housing configured to engage a mating connector during a mating operation. The electrical connector includes a contact array having electrical contacts coupled to the connector housing. Each of the electrical contacts includes an elongated body having a distal end and a proximal base. The elongated body is oriented with respect to a longitudinal axis that extends between the distal end and the proximal base and a lateral axis that is perpendicular to the longitudinal axis. The elongated body also has a body side extending along the longitudinal axis that is shaped to form a wipe track. The wipe track is configured to directly engage a contact finger of the mating connector that is moving substantially parallel to the longitudinal axis along a mating direction. The elongated body has a body width that extends along the lateral axis, and the wipe track has a track width that extends along the lateral axis. The track width is less than the body width for a majority of the wipe track. The wipe track has a path in which at least a portion of the path is non-parallel with respect to the longitudinal axis.
In an embodiment, an electrical contact is provided that includes a proximal base and an elongated body that extends from the proximal base to a distal end. The elongated body has a longitudinal axis extending between the proximal base and the distal end, and a lateral axis that is perpendicular to the longitudinal axis. The elongated body includes a body side that extends along the longitudinal and lateral axes and is shaped to form a wipe track. The wipe track is configured to engage a contact finger of a mating connector as the contact finger moves linearly along the longitudinal axis. The wipe track has a non-linear path such that the wipe track turns at least partially in a lateral direction as the wipe track moves toward the proximal base along the longitudinal axis.
Embodiments set forth herein may include electrical contacts, electrical connectors having the electrical contacts, and communication systems having the electrical connectors. Embodiments may be configured to reduce an accumulation of corrosive matter at a contact zone and/or improve electrical performance compared other known contacts, connectors, or systems. Embodiments may also reduce wear of the electrical contacts. Although the illustrated embodiment includes electrical connectors that are used in high-speed communication systems, such as backplane or midplane communication systems, it should be understood that embodiments may be used in other communication systems or in other systems/devices that utilize electrical connectors. Accordingly, the inventive subject matter is not limited to the illustrated embodiment.
In order to distinguish similar elements in the detailed description and claims, various labels may be used. For example, an electrical connector may be referred to as a header connector, a receptacle connector, or a mating connector. Electrical contacts may be referred to as header contacts, receptacle contacts, or mating contacts. When similar elements are labeled differently (e.g., receptacle contacts and mating contacts), the different labels do not necessarily require structural differences. For instance, in some embodiments, the receptacle contacts described herein may be referred to as mating contacts.
The circuit board assembly 102 includes a circuit board 110 having a first board side 112 and second board side 114. In some embodiments, the circuit board 110 may be a backplane circuit board, a midplane circuit board, or a motherboard. The circuit board assembly 102 includes a first header connector 116 mounted to and extending from the first board side 112 of the circuit board 110. The circuit board assembly 102 also includes a second header connector 118 mounted to and extending from the second board side 114 of the circuit board 110. The first and second header connectors 116, 118 include connector housings 117, 119, respectively. The first and second header connectors 116, 118 also include corresponding electrical contacts 120 that are electrically connected to one another through the circuit board 110. The electrical contacts 120 are hereinafter referred to as header contacts 120.
The circuit board assembly 102 includes a plurality of signal paths therethrough defined by the header contacts 120 and conductive vias 170 (shown in
The first and second header connectors 116, 118 include ground shields or contacts 122 that provide electrical shielding around corresponding header contacts 120. In an exemplary embodiment, the header contacts 120 are arranged in signal pairs 121 and are configured to convey differential signals. Each of the ground shields 122 may peripherally surround a corresponding signal pair 121. As shown, the ground shields 122 are C-shaped or U-shaped and cover the corresponding signal pair 121 along three sides.
The connector housings 117, 119 couple to and hold the header contacts 120 and the ground shields 122 in designated positions relative to each other. The connector housings 117, 119 may be manufactured from a dielectric material, such as a plastic material. Each of the connector housings 117, 119 includes a mounting wall 126 that is configured to be mounted to the circuit board 110 and shroud walls 128 that extend from the mounting wall 126. The shroud walls 128 cover portions of the header contacts 120 and the ground shields 122.
The first connector system 104 includes a first circuit board 130 and a first receptacle connector 132 that is mounted to the first circuit board 130. The first receptacle connector 132 is configured to be coupled to the first header connector 116 of the circuit board assembly 102 during a mating operation. The first receptacle connector 132 has a mating interface 134 that is configured to be mated with the first header connector 116. The first receptacle connector 132 has a board interface 136 configured to be mated with the first circuit board 130. In an exemplary embodiment, the board interface 136 is oriented perpendicular to the mating interface 134. When the first receptacle connector 132 is coupled to the first header connector 116, the first circuit board 130 is oriented perpendicular to the circuit board 110.
The first receptacle connector 132 includes a front housing or shroud 138. The front housing 138 is configured to hold a plurality of contact modules 140 side-by-side. As shown, the contact modules 140 are held in a stacked configuration generally parallel to one another. In some embodiments, the contact modules 140 hold a plurality of electrical contacts 142 (shown in
The second connector system 106 includes a second circuit board 150 and a second receptacle connector 152 coupled to the second circuit board 150. The second receptacle connector 152 is configured to be coupled to the second header connector 118 during a mating operation. The second receptacle connector 152 has a mating interface 154 configured to be mated with the second header connector 118. The second receptacle connector 152 has a board interface 156 configured to be mated with the second circuit board 150. In an exemplary embodiment, the board interface 156 is oriented perpendicular to the mating interface 154. When the second receptacle connector 152 is coupled to the second header connector 118, the second circuit board 150 is oriented perpendicular to the circuit board 110.
Similar to the first receptacle connector 132, the second receptacle connector 152 includes a front housing 158 used to hold a plurality of contact modules 160. The contact modules 160 are held in a stacked configuration generally parallel to one another. The contact modules 160 hold a plurality of receptacle contacts (not shown) that are electrically connected to the second circuit board 150. The receptacle contacts are configured to be electrically connected to the header contacts 120 of the second header connector 118. The receptacle contacts of the contact modules 160 may be similar or identical to the receptacle contacts 142 (
In the illustrated embodiment, the first circuit board 130 is oriented generally horizontally. The contact modules 140 of the first receptacle connector 132 are oriented generally vertically. The second circuit board 150 is oriented generally vertically. The contact modules 160 of the second receptacle connector 152 are oriented generally horizontally. As such, the first connector system 104 and the second connector system 106 may have an orthogonal orientation with respect to one another.
Although not shown, in some embodiments, the communication system 100 may include a loading mechanism. The loading mechanism may include, for example, latches or levers that fully mate the corresponding receptacle and header connectors. For instance, the loading mechanism may be operably coupled to the receptacle connector 132 and, when actuated, drive the receptacle connector 132 into the header connector 116 to assure that the receptacle and header connectors 132, 116 are fully mated.
The conductive vias 170 extend into the circuit board 110. In an exemplary embodiment, the conductive vias 170 extend entirely through the circuit board 110 between the first and second board sides 112, 114. In other embodiments, the conductive vias 170 extend only partially through the circuit board 110. The conductive vias 170 are configured to receive the header contacts 120 of the first and second header connectors 116, 118. For example, the header contacts 120 include compliant pins 172 that are configured to be loaded into corresponding conductive vias 170. The compliant pins 172 mechanically engage and electrically couple to the conductive vias 170. Likewise, at least some of the conductive vias 170 are configured to receive compliant pins 174 of the ground shields 122. The compliant pins 174 mechanically engage and electrically couple to the conductive vias 170. The conductive vias 170 that receive the ground shields 122 may surround the pair of conductive vias 170 that receive the corresponding pair of header contacts 120.
The ground shields 122 are C-shaped and provide shielding on three sides of the signal pair 121. The ground shields 122 have a plurality of walls, such as three planar walls 176, 178, 180. The planar walls 176, 178, 180 may be integrally formed or alternatively, may be separate pieces. The compliant pins 174 extend from each of the planar walls 176, 178, 180 to electrically connect the planar walls 176, 178, 180 to the circuit board 110. The planar wall 178 defines a center wall or top wall of the ground shield 122. The planar walls 176, 180 define side walls that extend from the planar wall 178. The planar walls 176, 180 may be generally perpendicular to the planar wall 178. In alternative embodiments, other configurations or shapes for the ground shields 122 are possible in alternative embodiments. For example, more or fewer walls may be provided in alternative embodiments. The walls may be bent or angled rather than being planar. In other embodiments, the ground shields 122 may provide shielding for individual header contacts 120 or sets of contacts having more than two header contacts 120.
The contact modules 140 are coupled to the front housing 138 such that the receptacle contacts 142 are received in corresponding contact openings 200. Optionally, a single receptacle contact 142 may be received in each contact opening 200. The contact openings 200 may be configured to receive corresponding header contacts 120 (
The front housing 138 may be manufactured from a dielectric material, such as a plastic material, and may provide isolation between the contact openings 200 and the contact openings 202. The front housing 138 may isolate the receptacle contacts 142 and the header contacts 120 from the ground shields 122. In some embodiments, the contact module 140 includes a conductive holder 210. The conductive holder 210 may include a first holder member 212 a second holder member 214 that are coupled together. The holder members 214, 214 may be fabricated from a conductive material. As such, the holder members 214, 214 may provide electrical shielding for the first receptacle connector 132. When the holder members 214, 214 are coupled together, the holder members 214, 214 define at least a portion of a shielding structure.
The conductive holder 210 is configured to support a frame assembly 220 that includes a pair of dielectric frames 230, 232. The dielectric frames 230, 232 are configured to surround signal conductors (not shown) that are electrically coupled to or include the receptacle contacts 142. Each signal conductor may also be electrically coupled to or may include a mounting contact 238. The mounting contacts 238 are configured to mechanically engage and electrically couple to conductive vias 262 of the first circuit board 130. Each of the receptacle contacts 142 may be electrically coupled to a corresponding mounting contact 238 through the signal conductor (not shown).
In the illustrated embodiment, the receptacle contacts 142 are identical. As such, the following description is applicable to each of the receptacle contacts 142. It should be understood, however, that the receptacle contacts 142 of the signal pair 141 are not required to be identical. It should also be understood that the receptacle contacts 142 of the corresponding receptacle connector are not required to be identical. For example, in some embodiments, the receptacle contacts may be configured differently so that the receptacle contacts electrically engage the corresponding header contacts at different times during the mating operation.
Each of the contact fingers 302, 304 includes a base portion 306, a beam portion 308, and a joint portion 310. The beam portions 308 extend to respective mating interfaces 312, which are defined between opposite edge portions 470, 472. The mating interfaces 312 of the contact fingers 302, 304 face each other with a contact-receiving gap 314 therebetween. In the illustrated embodiment, the corresponding mating interfaces 312 of the contact fingers 302, 304 are substantially paddle-shaped or tab-shaped. The mating interface 312 includes a flared portion 313 that extends away from the opposing mating interface 312 to enlarge the contact-receiving gap 314. The curved contour of the mating interfaces 312 and the flared portions 313 may facilitate receiving one of the header contacts 120 (
In
When the contact fingers 302, 304 are in deflected conditions, each of the contact fingers 302, 304 may generate a normal force that presses the corresponding mating interface 312 against the corresponding header contact 120 in a direction toward the other mating interface 312. As such, the contact fingers 302, 304 may pinch the corresponding header contact 120 therebetween. To this end, each of the contact fingers 302, 304 may be configured to provide a designated normal force when the corresponding contact finger is in a deflected condition. For example, the base portion 306 may have a designated length 316, the beam portion 308 may have a designated length 318, and the joint portion 310 may have a designated shape or contour. Each of the contact fingers 302, 304 may also have a designated thickness 319. In an exemplary embodiment, the thickness 319 is substantially uniform throughout the corresponding contact finger. The lengths 316, 318, the shape of the joint portion 310, and the thickness 319 may be configured such that each of the contact fingers 302, 304 provides a designated normal force against the header contact 120. The lengths 316, 318 and the shape of the joint portion 310 may also be configured to locate the mating interface 312 at a designated location along the header contact 120 (
As shown in
In the illustrated embodiment, the header contact 120 has a linear structure from the board end 404 to the distal end 402. In other embodiments, the header contact 120 may not be linear from the board end 404 to the distal end 402. For example, the elongated body 412 may be linear and extend along the longitudinal axis between the distal end 402 and the proximal base 410 as shown in
The elongated body 412 includes body sides 421, 422, 424 and a body side 423 (shown in
In the illustrated embodiment, the wipe track 432 includes, sequentially, a first track segment 441, a second track segment 442, and a third track segment 443. The third track segment 443 includes an end 444 of the wipe track 432 that is coupled to the contact zone 438. During the mating operation, the mating interface 312 (
During the mating operation, the mating interface 312 moves in a generally linear manner along the longitudinal axis 406. On the other hand, a path 448 of the wipe track 432 is non-linear such that the wipe track 432 turns at least partially in a lateral direction 447 as the wipe track 432 moves toward the proximal base 410 (
The elongated body 412 has a body width 450 and the wipe track 432 has a track width 452. Each of the body width 450 and the track width 452 may be measured along the lateral axis 408. In some embodiments, the track width 452 for at least a portion of the wipe track 432 may be less than the body width 450 of the elongated body 412. For example, in the illustrated embodiment, a majority of the wipe track 432 has a track width 452 that is less than the body width 450. More particularly, the track width 452 for at least a portion of the wipe track 432 may be less than the body width 450 at the contact zone 438. As specific examples, the track width 452 may be less than the body width 450 for at least 60% of the wipe track 432, for at least 70% of the wipe track 432, or for at least 80% of the wipe track 432. In particular embodiments, the track width 452 may be less than the body width 450 for the entire or nearly the entire wipe track 432.
Also shown, the track width 452 is substantially common or uniform along the first track segment 441, the second track segment 442, and a majority of the third track segment 443. As shown, the track width 452 at the end 444 of the wipe track 432 increases to be substantially equal to the body width 450 at the contact zone 438. Accordingly, the track width 452 is less than the body width 450 throughout the wipe track 432 in the illustrated embodiment. In other embodiments, however, the track width 452 may be equal to the body width 450 for one or more portions of the wipe track 432. For example, in an alternative embodiment, the track width 452 along the second track segment 442 may be substantially equal to the body width 450.
As shown in
In some embodiments, the path 448 of the wipe track 432 may be represented by a center line that extends between the two track edges 460, 462 of the wipe track 432. The center line may be defined by as a series of points that are located halfway between the track edges 460, 462. As shown in
In an exemplary embodiment, the header contact 120 is stamped from sheet metal having opposite side surfaces with a thickness extending therebetween. When the header contact 120 is stamped, the body sides 421, 423 may be formed from the opposite side surfaces of the sheet metal, and the body sides 422, 424 may be stamped edges. The stamping process may provide the recessed portions 428-430 and thereby form the wipe track 432. The elongated body 412 may have a substantially uniform thickness that is measured between the first and second body sides 421, 423 and a width that is measured between the body sides 422, 424. In an exemplary embodiment, the thickness and width are substantially equal.
After stamping an unfinished header contact 120 from the sheet metal, the header contact 120 may be treated to include designated coatings. By way of example only, the sheet metal may include a copper alloy. After stamping the header contact 120 from the copper alloy, a first coating (not shown) may be applied directly to the copper alloy base. A second coating (not shown) may be applied onto the first coating. The first and second coatings may be applied using, for example, an electroplating process. In an exemplary embodiment, the first coating includes nickel or tin and the second coating includes gold. In particular embodiments, the gold is selectively located at the contact zone 438 and not along the wipe track 432. In an exemplary embodiment, the header contact 120 may include a third coating that is configured to prevent moisture from contacting the second coating.
As shown in
The body side 421 is shaped such that the wipe track 432 has different lateral positions along the lateral axis 408 with respect to the opposite body sides 422, 424. For example, the wipe track 432 extends laterally between the track edges 460, 462 as shown in
With respect to
As shown in
The body side 504 is shaped to include a wipe track 508 and a contact zone 510. Similar to the wipe track 432 (
Embodiments set forth herein may be configured such that the mating interface of the corresponding contact finger, such as the mating interface 312 (
It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-described embodiments (and/or aspects thereof) may be used in combination with each other. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Dimensions, types of materials, orientations of the various components, and the number and positions of the various components described herein are intended to define parameters of certain embodiments, and are by no means limiting and are merely exemplary embodiments. Many other embodiments and modifications within the spirit and scope of the claims will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.
As used in the description, the phrase “in an exemplary embodiment” and the like means that the described embodiment is just one example. The phrase is not intended to limit the inventive subject matter to that embodiment. Other embodiments of the inventive subject matter may not include the recited feature or structure. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means—plus-function format and are not intended to be interpreted based on 35 U.S.C. §112, sixth paragraph, unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure.
| Number | Name | Date | Kind |
|---|---|---|---|
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| 5135414 | van Dijk | Aug 1992 | A |
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| 5775963 | Byfield, Jr. | Jul 1998 | A |
| 6755699 | Beers | Jun 2004 | B2 |
| 20060205290 | Narita | Sep 2006 | A1 |
| 20120178317 | Skidmore | Jul 2012 | A1 |
| Number | Date | Country | |
|---|---|---|---|
| 20160006192 A1 | Jan 2016 | US |
