The subject matter herein relates generally to electrical connectors, and more particularly, to board-to-board electrical connectors that are configured to communicate data signals between different circuit boards.
Various communication or computing systems use electrical connectors for transmitting data signals between circuit boards in the system. For example, conventional board-to-board connectors may include signal contacts that electrically connect contact pads of a daughter card to corresponding contact pads of a motherboard. Edge connectors are one type of board-to-board connector. Edge connectors are configured to receive an edge of the daughter card to electrically connect to the daughter card as well as hold the daughter card in a desired position. For example, edge connectors may include one or more recesses that are sized to receive a thickness of the daughter card. The daughter card includes contact pads that are located near the edge of the daughter card. When the edge of the daughter card is inserted into the recess(es), the signal contacts electrically connect with the contact pads of the daughter card. The daughter card may be held within the recess through an interference fit and/or the electrical connector may include a fastening mechanism, such as removable latches, screws, and the like, to hold the daughter card.
However, conventional edge connectors may have certain limitations. For example, it may be desirable to reduce the required space of an electrical connector within a system and/or use signal contacts that transmit at high speeds (e.g., 5-10 Gbs or higher). Reducing the required space of an electrical connector may be accomplished by reducing a centerline spacing between the signal contacts and/or reducing the size of the signal contacts. However, reducing the centerline spacing may lead to an increase in unwanted noise. Also, signal contacts of a reduced size may be unable to perform as required. Furthermore, it may be desirable for the edge connectors to include power contacts as well as signal contacts. However, power contacts may complicate the manufacturing of the electrical connectors thereby increasing the costs.
Accordingly, there is a need for edge connectors that are capable of transmitting data signals at higher speeds than known edge connectors. Furthermore, there is a need for edge connectors that have a greater density of signal contacts than known edge connectors. There is also a general need for edge connectors that are less costly to manufacture.
In one embodiment, an electrical connector configured to interconnect first and second circuit boards is provided. The electrical connector includes a connector housing having opposite mating and loading faces that are configured to engage board edges of the first and second circuit boards, respectively. The connector housing includes a contact channel that extends through the connector housing between the mating and loading faces. The electrical connector also includes a signal contact that is stamped from sheet material. The signal contact includes a contact body having opposite sheet surfaces and a stamped edge extending therebetween. The stamped edge defines a shape of the contact body that includes first and second contact fingers. The signal contact is disposed within the contact channel so that the stamped edge along the first contact finger electrically connects with a contact pad of the first circuit board and so that the stamped edge along the second contact finger electrically connects with a contact pad of the second circuit board.
In another embodiment, an electrical connector configured to interconnect first and second circuit boards is provided. The electrical connector includes a connector housing having opposite mating and loading faces that are configured to engage board edges of the first and second circuit boards, respectively. The connector housing includes a contact channel that extends through the connector housing between the mating and loading faces. The electrical connector also includes a signal contact stamped from sheet material. The signal contact includes a contact body having opposite sheet surfaces and a stamped edge extending therebetween. The opposite sheet surfaces extend parallel to a body plane substantially throughout the contact body. The contact body includes a base portion and first and second contact fingers that extend from the base portion in substantially opposite directions. The connector housing is configured to hold the base portion within the contact channel and the first and second contact fingers are configured to flex relative to the base portion and within the body plane when the first and second contact fingers engage the first and second circuit boards, respectively.
In the illustrated embodiment, the electrical connector 100 is an edge connector that holds the circuit boards 116 and 118 in a substantially coplanar relationship. As such, the electrical connector 100 may also be referred to as edge-to-edge or straddle-mount connector. However, in alternative embodiments, the circuit boards 116 and 118 may be held by the electrical connector 100 in different positional relationships, such as at a right-angle relationship, an orthogonal relationship, or in a stacked relationship where the circuit boards 116 and 118 extend parallel to each other. Also, the circuit boards 116 and 118 may be held in a stair-like manner where the circuit boards 116 and 118 extend along separate parallel planes and may or may not at least partially overlap each other.
The connector housing 101 is configured to receive and hold electrical contacts for electrically connecting the circuit boards 116 and 118 to each other. For example, the electrical connector 100 may include signal contacts 120 that are disposed within the connector housing 101 and are configured to transmit data signals. In some embodiments, the signal contacts 120 are configured to transmit high-speed data signals, such as data signals greater than about 5 gigabits/second (Gbs) or, more particularly, data signals greater than about 10 Gbs. Furthermore, the signal contacts 120 may be stamped from sheet material and positioned so that a stamped edge of the signal contact 120 engages both of the circuit boards 116 and 118. In such embodiments, the signal contacts 120 may permit a centerline spacing that is smaller than a centerline spacing of other known electrical connectors, which may use profiled-and-formed signal contacts unlike solely profiled signal contacts like those described with respect to the illustrated embodiment. For example, the signal contacts 120 may be stamped from sheet material having a thickness of less than about 0.010 inches. In particular embodiments, the sheet material may be about 0.008 inches. In more particular embodiments, the sheet material may be less than about 0.005 inches or less than about 0.002 inches. However, the signal contacts 120 may be stamped from sheet material having a thickness greater than about 0.010 inches. Furthermore, as will be described in greater detail below, the signal contacts 120 may include contact fingers that engage the circuit boards 116 and 118 and that move within a common body plane BP1 (
Furthermore, the electrical connector 100 may include power contacts 122 disposed within the connector housing 101 and that are configured to transmit power between the circuit boards 116 and 118. For example, the power contacts 122 may be configured to transmit greater than about 6 amperes (A) or, more particularly, greater than about 10 A. In particular embodiments, the connector housing 101 has tool indentations 130 where a stake, or other similar tool, has pressed material of the connector housing 101 into the power contacts 122 to facilitate holding the power contacts 122 therein. The material may be deformed to surround the power contacts 122. Such processes may be referred to as cold-staking processes.
As shown in
Also shown in
As shown in
Also shown in
In some embodiments, the connector housing 101 comprises a single piece of material that includes the features described herein with respect to the connector housing 101. For example, the connector housing 101 may comprise an insulative material that has been formed into shape by an injection molding process. In such embodiments, the electrical contacts may be held by the connector housing 101 through interference fits and/or cold-stake processing. In particular embodiments, the signal contacts 120 are held by the connector housing 101 through interference fits, and the power contacts 122 are held through a cold-staking process.
In the illustrated embodiment, the electrical connector 100 includes only two types of electrical contacts, the signal contacts 120 and the power contacts 122. However, in alternative embodiments, the electrical connector 100 may include additional types of signal contacts that are manufactured in different manners and/or have different shapes than the signal contacts 120. The electrical connector 100 may also include additional power contacts that are manufactured in different manners and/or have different shapes than the power contacts 122. Furthermore, in the illustrated embodiment, the electrical connector 100 includes a plurality of signal contacts 120 and a plurality of power contacts 122. In some embodiments, the electrical connector 100 may include only a single signal contact 120 and/or only a single power contact 122.
As shown, the signal contact 120 includes a contact body 202 having opposite sheet surfaces 204 and 206 and a stamped edge 210 that extends between the sheet surfaces 204 and 206. The sheet surfaces 204 and 206 may extend parallel to each other and also extend parallel to and define a body plane BP2. The body plane BP2 extends parallel to the longitudinal and vertical axes 292 and 291. In the illustrated embodiment, the stamped edge 210 defines a shape or contour of the contact body 202. As such, the stamped edge 210 may extend along a path that substantially coincides with the body plane BP2. For example, a centerline CL1 (indicated by a dashed line) that extends along a center of the stamped edge 210 between the sheet surfaces 204 and 206 may extend within the body plane BP2. More specifically, a path made by the centerline CL1 may essentially only exist in the board plane BP2.
The stamped edge 210 may be formed when a tool or cutting device (not shown) stamps the contact body 202 from a sheet of material. The tool or cutting device may be configured to stamp the sheet material so that the signal contact 120 includes predetermined features. For example, the stamped edge 210 may define a base portion 212 and first and second contact lingers 214 and 216. The contact fingers 214 and 216 extend from the base portion 212 in generally opposite directions away from each other and along the longitudinal axis 292. In particular embodiments, the first contact finger 214 may be a leading contact finger that is first inserted into the connector housing 101, and the second contact finger may be a trailing contact finger that is not inserted through the connector housing 101.
The base portion 212 is shaped relative to the contact channel 150 (
The contact finger 214 may include a leading end 230 of the contact body 202, and the contact finger 216 may include a trailing end 232 of the contact body 202. A length L1 of the contact body 202 may extend between the leading and trailing ends 230 and 232 along the longitudinal axis 292. The contact finger 214 may be shaped to include a longitudinal portion 242 that extends from the arm 222 and an intermediate portion 244 that extends from the longitudinal portion 242 toward the leading end 230. The longitudinal portion 242 may extend in a direction along the longitudinal axis 292, and the intermediate portion 244 may extend in a linear manner from the longitudinal portion 242. As shown, the longitudinal and intermediate portions 242 and 244 may extend in slightly different directions such that the longitudinal and intermediate portions 242 and 244 form an angle θ1 between each other. The angle θ1 may be less than 180°.
The contact finger 214 also includes a distal portion 246 having a protrusion 248. The protrusion 248 is configured to electrically connect (i.e., make electrical contact with) to the circuit board 116 (
Likewise, the contact finger 216 may be shaped to include a longitudinal portion 252 that extends from the arm 224 and an intermediate portion 254 that extends from the longitudinal portion 252. The longitudinal portion 252 may extend in a direction along the longitudinal axis 292, and the intermediate portion 254 may extend in a linear manner from the longitudinal portion 252. As shown, the longitudinal and intermediate portions 252 and 254 may extend in slightly different directions such that the longitudinal and intermediate portions 252 and 254 form an angle θ2 between each other. The angle θ2 may be less than 180°. In the illustrated embodiment, the angle θ2 is less than the angle θ1.
The contact finger 216 also includes a distal portion 256 having a protrusion 258 that is configured to electrically connect to the circuit board 118 (
In the illustrated embodiment, the contact body 202 comprises a substantially planar structure. For example, the contact body 202 may have a thickness T1 that extends between the sheet surfaces 204 and 206. As such, the thickness T1 may represent a width Ws of the stamped edge 210. The thickness T1 may be substantially uniform throughout the contact body 202. The thickness T1 may have values similar to the thickness of sheet material described above. For example, the thickness T1 may be less than about 0.010 inches, about 0.008 inches, or less than about 0.002 inches. As described above, the sheet surfaces 204 and 206 may extend substantially parallel to each other and define the body plane BP2. Furthermore, in the illustrated embodiment, the thickness T1 is generally smaller than a dimension of the sheet surface 204 or the sheet surface 206. For example, the thickness T1 is smaller than a width W1 of the longitudinal portion 242 or a width W2 of the intermediate portion 244. As such, the contact fingers 214 and 216 may provide greater resistance against deflection.
As shown in the cut-out portion of
Although the following description is with specific reference to the contact channel 150A, the description may also be applicable to the contact channel 150B. The contact-insertion space 324A of the contact channel 150A may be sized to permit the signal contact 120A to be inserted into the contact channel 150A and form an interference fit with the connector housing 101. For example, when assembling the electrical connector 100, the leading end 230A of each signal contact 120A may approach the contact-insertion space 324A from the loading face 108. More specifically, the signal contact 120A may be advanced in a substantially linear manner toward the mating face 106 in a loading direction LS (indicated by the arrow) that extends from the loading face 108 to the mating face 106. In some embodiments, the distal portion 246A may move through the contact-insertion space 324A without being obstructed or deflected by the connector housing 101 (e.g., the interior surfaces 326A and 328A). However, in the exemplary embodiment, the signal contact 120A may approach the contact-insertion space 324A at a slight angle to permit the distal portion 246A to move between the interior surfaces 326A and 328A.
After the distal portion 246A clears the contact-insertion space 324A, the intermediate and longitudinal portions 244A and 242A also move therethrough until the base portion 212A is received within the contact-insertion space 324A. When the base portion 212A moves into the contact-insertion space 324A, the base portion 212A may form an interference fit with the opposing interior surfaces 326A and 328A. For example, the base portion 212A may be compressed between the interior surfaces 326A and 328A. The grip member 215A may facilitate preventing the signal contact 120A from being removed from the contact channel 150A. As shown, the connector housing 101 may also include a shoulder 330A that provides a positive stop to prevent the base portion 212A from moving further through the contact channel 150A when inserted. When the electrical connector 100 is fully assembled, the protrusion 248A may clear the wall edge 352A so that the edge-interface area 249A is located within the board-receiving recess 124. However, in alternative embodiments, the edge-interface area 249A may not clear the wall edge 352A and, instead, may be disposed between the adjacent sidewalls 350A.
Also shown in
When the circuit board 116 is advanced into the board-receiving recess 124 in a direction along the longitudinal axis 192 (
When the circuit board 118 is advanced into the board-receiving region 140 in a direction along the longitudinal axis 192, the circuit board 118 slides between the signal contacts 120A and 120B. As the circuit board 118 slides therealong, the stamped edges 210A and 210B engage the circuit board 118 thereby deflecting the contact fingers 216A and 216B away from the circuit board 118 in opposite directions. Similar to the contact fingers 214A and 214B, the contact fingers 216A and 216B may move within the body plane BP2. The stamped edges 210A and 210B slide along the board surfaces 274 and 276, respectively. The edge-interface areas 259A and 259B slide along the board surfaces 274 and 276, respectively, until the edge-interface areas 259A and 25913 electrically connect with the contact pads 275 and 277, respectively. In some embodiments, the edge-interface areas 259A and 259B may then be soldered to the corresponding contact pads 275 and 277. Accordingly, the contact fingers 214 and 216 of one signal contact 120 may move in a common direction when engaged by the respective circuit boards 116 and 118. For example, when the circuit boards 116 and 118 engage the signal contact 120A, the contact fingers 214A and 216A are configured to independently flex in a common direction within the body plane BP2 with respect to the base portion 212A. Unlike other, known electrical connectors, the stamped edge 210A electrically connects with both circuit boards 116 and 118 through the edge-interface areas 249A and 259A.
The power contact 122A may be coupled to the connector housing 101 through a cold-staking process. When the material of the connector housing 101 is not fully set, a tool (not shown) may press the cavity wall 306 toward the power contact 122A thereby forming the tool indentations 130. When the cavity wall 306 is pressed, the material of the cavity wall 306 is deformed and surrounds the coupling projections 310 of the contact body 308. The material of the connector housing 101 may then set into a final shape. As such, the material surrounding the coupling projections 310 prevents the power contact 122A from being removed from the connector housing 101.
Also shown, the mounting features 332 and 334 are configured to be mounted onto the circuit board 118 and coupled thereto. The passages 333 and 335 (
It is to be understood that the above description is intended to be illustrative, and not restrictive. In addition, the above-described embodiments (and/or aspects or features thereof) may be used in combination with each other. Furthermore, 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. 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 |
---|---|---|---|
3923364 | Shapiro et al. | Dec 1975 | A |
5277621 | Seto | Jan 1994 | A |
5584708 | Leong | Dec 1996 | A |
6231355 | Trammel et al. | May 2001 | B1 |
6508661 | Yu | Jan 2003 | B1 |
6520797 | Okamura et al. | Feb 2003 | B2 |
6652322 | Ito et al. | Nov 2003 | B2 |
6692273 | Korsunsky et al. | Feb 2004 | B1 |
6722915 | McAlonis et al. | Apr 2004 | B1 |
7416452 | Sabo | Aug 2008 | B1 |
7527511 | Peng et al. | May 2009 | B1 |
7553163 | McAlonis et al. | Jun 2009 | B2 |