Patent Application
20140357133
The subject matter herein relates generally to contact modules for receptacle assemblies.
Some electrical systems, such as network switches and computer servers with switching capability, include receptacle connectors coupled to circuit boards, such as backplanes, daughtercards, switch cards, line cards and the like. The receptacle connectors typically include individual contact modules or chicklets that have signal contacts configured to be terminated to the circuit boards. Some conventional contact modules include overmolded leadframes. The conductors of the leadframes are typically held during the overmolding process by pinch pins. The pinch pins are blunt round pinch pins that press against opposite sides of the conductors to hold the conductors during overmolding.
The conventional overmolding process is not without disadvantages. For instance, the dielectric material that is injected into the mold used to form the contact module tends to press against the conductors and cause the conductors to move during the overmolding process. Lateral offset of the conductors from the designed nominal position causes signal integrity issues.
A need remains for an improved contact module. A need remains for components and methods of fixing lateral positions of conductors during overmolding to maintain proper signal integrity.
In one embodiment, a contact module for a receptacle assembly is provided that includes a frame assembly having first and second frames coupled together. The first and second frames each have a corresponding leadframe having a plurality of receptacle signal contacts. The first and second frames each have at least two frame members spaced apart from each other by a corresponding gap. Each frame member is overmolded over and supports corresponding receptacle signal contacts. The first and second frames are interested such that at least one frame member of the first frame is received in a corresponding gap of the second frame and such that at least one frame member of the second frame is received in a corresponding gap of the first frame. The receptacle signal contacts are supported by corresponding removable inserts during overmolding of the corresponding frame members. Each removable insert leaves a window in the corresponding frame member exposing the corresponding receptacle signal contacts. The first frame includes a first dielectric insert extending from a corresponding frame member of the first frame into the gap. The first dielectric insert is received in a corresponding window in the second frame to substantially fill the window and cover the corresponding receptacle signal contacts of the second frame. The second frame includes a second dielectric insert extending from a corresponding frame member of the second frame into the gap. The second dielectric insert is received in a corresponding window in the first frame to substantially fill the window and cover the corresponding receptacle signal contacts of the first frame.
Optionally, the removable insert may hold lateral positions of the receptacle signal contacts relative to each other during overmolding. The removable insert may include a finger positioned between the corresponding receptacle signal contacts to hold a lateral position of the receptacle signal contacts relative to one another. The first dielectric insert may have a complementary shape as the corresponding removable insert to substantially fill the window left by removal of the removable insert.
Optionally, the removable insert may include a main wall, end walls extending from the main wall and forming a receiving space therebetween, and a finger extending from the main wall in the receiving space. First and second channels may be formed between the finger and the corresponding end walls. The first and second channels may receive the receptacle signal contacts. The finger and end walls may hold the lateral positions of the receptacle signal contacts relative to each other during the overmolding process. The receiving space may be filled with dielectric material during overmolding of the corresponding frame member.
Optionally, the removable insert may maintain a predetermined spacing between a differential pair of receptacle signals contacts as the dielectric material of the frame member is overmolded to form the corresponding frame member. The frame members may include edges facing corresponding gaps. The edges at the windows may be inset such that the frame member is narrower at the window than along segments of the frame member adjacent the window.
In another embodiment, a contact module for a receptacle assembly is provided including a frame having a leadframe that includes a plurality of receptacle signal contacts and frame member overmolded over corresponding receptacle signal contacts. The frame members are separated by corresponding gaps. A removable insert is coupled to a corresponding receptacle signal contacts. The removable insert has a main wall, end walls extending from the main wall and forming a receiving space therebetween, and a finger extending from the main wall in the receiving space. First and second channels are formed between the finger and the corresponding end walls. The first and second channels receive the receptacle signal contacts. The finger and end walls hold the lateral positions of the receptacle signal contacts relative to each other during the overmolding process. The receiving space is filled with dielectric material during overmolding of the corresponding frame member. The removable insert leaves a window in the corresponding frame member after the removable insert is removed. The window exposes the corresponding receptacle signal contacts.
The midplane assembly 102 includes a midplane circuit board 110 having a first side 112 and second side 114. The midplane assembly 102 includes a first header assembly 116 mounted to and extending from the first side 112 of the midplane circuit board 110. The midplane assembly 102 includes a second header assembly 118 mounted to and extending from the second side 114 of the midplane circuit board 110. The first and second header assemblies 116, 118 each include header signal contacts 120 electrically connected to one another through the midplane circuit board 110.
The midplane assembly 102 includes a plurality of signal paths therethrough defined by the header signal contacts 120 and conductive vias that extend through the midplane circuit board 110. Each signal path through the midplane assembly 102 is defined by a header signal contact 120 of the first header assembly 116 and a header signal contact 120 of the second header assembly 118 both received in a common conductive via through the midplane circuit board 110. In an exemplary embodiment, the signal paths pass straight through the midplane assembly 102 along linear paths. Such a design of the midplane circuit board 110 is less complex and less expensive to manufacture than a circuit board that routes traces between different vias to connect the first and second header assemblies 116, 118.
In an exemplary embodiment, the first and second header assemblies 116, 118 may be identical to one another. Having the first and second header assemblies 116, 118 identical to one another reduces the overall number of different parts that are needed for the connector system 100. The first and second header assemblies 116, 118 may have an identical pinout allowing the first and second header assemblies 116, 118 to be mounted to the midplane circuit board 110 using conductive vias that pass straight through the midplane circuit board 110 between the first side 112 and the second side 114. The first and second header assemblies 116, 118 are not rotated 90° relative to one another as is typical of conventional connector systems, and thus do not suffer from a loss in density or a loss in performance as is typical of such connector systems. The header assemblies 116, 118 may be rotated 180° relative to one another to facilitate different card positions.
The first and second header assemblies 116, 118 include header ground shields 122 that provide electrical shielding around corresponding header signal contacts 120. In an exemplary embodiment, the header signal contacts 120 are arranged in pairs configured to convey differential signals. The header ground shields 122 peripherally surround a corresponding pair of the header signal contacts 120.
The first connector assembly 104 includes a first circuit board 130 and a first receptacle assembly 132 coupled to the first circuit board 130. The first receptacle assembly 132 is configured to be coupled to the first header assembly 116. The first receptacle assembly 132 includes a receptacle housing 138 that holds a plurality of contact modules 140. The contact modules 140 are held in a stacked configuration generally parallel to one another. The contact modules 140 hold a plurality of receptacle signal contacts (not shown) that are electrically connected to the first circuit board 130 and define signal paths through the first receptacle assembly 132. Optionally, the receptacle signal contacts may be arranged in pairs carrying differential signals.
The second connector assembly 106 includes a second circuit board 150 and a second receptacle assembly 152 coupled to the second circuit board 150. The second receptacle assembly 152 is configured to be coupled to the second header assembly 118. The second receptacle assembly 152 has a header interface 154 configured to be mated with the second header assembly 118. The second receptacle assembly 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 with respect to the header interface 154. When the second receptacle assembly 152 is coupled to the second header assembly 118, the second circuit board 150 is oriented perpendicular with respect to the midplane circuit board 110. The second circuit board 150 is oriented perpendicular to the first circuit board 130.
The second receptacle assembly 152 includes a receptacle housing 158 that holds 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 signal contacts 162 (shown in
In the illustrated embodiment, the first circuit board 130 is oriented generally horizontally. The contact modules 140 of the first receptacle assembly 132 are orientated generally vertically. The second circuit board 150 is oriented generally vertically. The contact modules 160 of the second receptacle assembly 152 are oriented generally horizontally. The first connector assembly 104 and the second connector assembly 106 have an orthogonal orientation with respect to one another. The signal contacts within each differential pair, including the receptacle signal contacts of the first receptacle assembly 132, the receptacle signal contacts 162 of the second receptacle assembly 152, and the header signal contacts 120, are all oriented generally horizontally. The contact modules 140 and/or 160 may be configured to be terminated to cables rather than circuit boards, with conductors of the cables terminated to corresponding conductors of the contact modules 140, and/or 160.
The holder members 312, 314 are fabricated from a conductive material. For example, the holder members 312, 314 may be die cast from a metal material. Alternatively, the holder members 312, 314 may be stamped and formed or may be fabricated from a plastic material that has been metalized or coated with a metallic layer. By having the holder members 312, 314 fabricated from a conductive material, the holder members 312, 314 may provide electrical shielding for the second receptacle assembly 152. When the holder members 312, 314 are coupled together, the holder members 312, 314 define at least a portion of a shield structure to provide electrical shielding for the receptacle signal contacts 162. The conductive holder 310 may be manufactured from a single piece rather than the two holder members 312, 314. In other embodiments, the holder 310 may not be conductive, but rather may rely on separate shields or may be unshielded.
The conductive holder 310 holds a frame assembly 320, which includes the receptacle signal contacts 162. The holder members 312, 314 provide shielding around the frame assembly 320 and receptacle signal contacts 162. The holder members 312, 314 include tabs 322, 324 that extend inward toward one another to extend into the frame assembly 320. The tabs 322, 324 define at least a portion of a shield structure that provides electrical shielding around the receptacle signal contacts 162. The tabs 322, 324 are configured to extend into the frame assembly 320 such that the tabs 322, 324 are positioned between pairs of the receptacle signal contacts 162 to provide shielding between the corresponding pairs of the receptacle signal contacts 162.
The frame assembly 320 includes a first frame 330 and a second frame 332 that surround corresponding receptacle signal contacts 162. Optionally, the first frame 330 may be manufactured from a dielectric material overmolded over the corresponding receptacle signal contacts 162. The second frame 332 may be manufactured from a dielectric material overmolded over the corresponding receptacle signal contacts 162. The first and second frames 330, 332 are coupled together to form the frame assembly 320. In alternative embodiments, rather than having the two frames 330, 332, the frame assembly 320 may include only a single frame or may include more than two frames.
In an exemplary embodiment, the receptacle signal contacts 162 of the first frame 330 form part of a common leadframe 360 (shown in
The holder members 312, 314 provide electrical shielding between and around respective pairs of the receptacle signal contacts 162. The holder members 312, 314 provide shielding from electromagnetic interference (EMI) and/or radio frequency interference (RFI). The holder members 312, 314 may provide shielding from other types of interference as well. The holder members 312, 314 prevent crosstalk between different pairs of receptacle signal contacts 162. The holder members 312, 314 provide electrical shielding around the outside of the first and second frames 330, 332, and thus around the outside of all of the receptacle signal contacts 162, as well as between the receptacle signal contacts 162, such as between pairs of receptacle signal contacts 162 separated by the tabs 322, 324. The holder members 312, 314 control electrical characteristics, such as impedance control, crosstalk control, and the like, of the receptacle signal contacts 162. The holder members 312, 314 provide shielding for the receptacle signal contacts 162 from adjacent contact modules.
In an exemplary embodiment, the contact module 160 includes a first ground shield 350 and a second ground shield 352 that provide shielding for the receptacle signal contacts 162. The ground shields 350, 352 make ground terminations to the header ground shields 122 (shown in
The first ground shield 350 includes grounding beams 354 extending from a front thereof. The second ground shield 352 includes grounding beams 356 extending from a front thereof. The grounding beams 354, 356 extend along different sides of the receptacle signal contacts 162 to provide electrical shielding and electrical grounding. The grounding beams 354, 356 are configured to engage and be electrically connected to the header ground shields 122 (shown in
As illustrated in
A removable insert 370 is illustrated in
The removable insert 370 holds the nominal positions of the differential pair of receptacle signal contacts 162 relative to each other during overmolding. For example, the removable insert 370 stops one or both receptacle signal contacts 162 from moving toward or away from one another and/or from moving out of the plane of the leadframe 360. Any of the receptacle signal contacts 162 may be held by removable inserts 370 and any number of removable inserts 370 may be used as necessary to hold the receptacle signal contacts 162. For example, shorter lengths of the receptacle signal contacts 162 (e.g. the interior pairs of receptacle signal contacts 162) may not need removable inserts 370 as the receptacle signal contacts 162 may be sufficiently held by the carrier without significant movement thereof
The frame members 400 extend between a mating end 404 of the first frame 330 and a mounting end 406 of the first frame 330. In the illustrated embodiment, the mating end 404 is generally perpendicular with respect to the mounting end 406; however other orientations are possible in alternative embodiments. The mating portions 364 of the receptacle signal contacts 162 extend from the frame members 400 beyond the mating end 404 and the mounting portions 366 extend from the frame members 400 beyond the mounting end 406 for electrical termination to other components such as the second header assembly 118 and the second circuit board 150 (both shown in
The frame members 400 are connected by bridges 408 that span the gaps 402. The bridges 408 position the frame members 400 with respect to one another. In an exemplary embodiment, the bridges 408 are located proximate to the mating end 404 and the mounting end 406 of the first frame 330. The bridges 408 are co-molded with the frame members 400. The bridges 408 define flow paths for the dielectric material of the frame members 400 during the molding (e.g. injection molding) process. For example, the dielectric material may be injected into the mold at gating points (generally identified at points GP) which are located along the outer-most frame member 400 and the dielectric material flows through the bridges into the interior frame members 400 to mold the entire frame 330. Any number of gating points may be provided. The gating points GP may be located on interior frame members 400 in addition to, or in lieu of, the outer frame member 400. The force from the injection of the dielectric material at the gating points may cause pressure and shifting of the receptacle signal contacts 162 of the leadframe 360 (shown in
During the overmolding process, a majority of the leadframe 360 is encased in a dielectric material which forms the frame members 400. The mating portions 364 extend from the mating end 404 along an edge of the frame members 400 (e.g. a front edge), and the mounting portions 366 extend from the mounting end 406 along another edge of the frame members 400 (e.g. a side edge).
The receptacle signal contacts 162 are arranged in pairs. One of the receptacle signal contacts 162 in each pair defines a radially inner receptacle signal contact (measured from the intersection between the mating and mounting ends of the contact module 160), while the other receptacle signal contact 162 in each pair defines a radially outer receptacle signal contact. The inner and outer receptacle signal contacts 162 have different lengths between the mating portions 364 and the mounting portions 366. In an exemplary embodiment, the radially outer receptacle signal contacts 162 are exposed to air through the frame members 400 for electrical compensation, such as to reduce electrical skew.
The frame members 400 include locating posts 430 extending therefrom. The locating posts 430 are configured to be received in corresponding openings in the conductive holder 310 (shown in
In an exemplary embodiment, at least some of the frame members 400 include troughs 434. The troughs 434 are recessed areas that are configured to receive portions of the second frame 332 (shown in
In an exemplary embodiment, the bridges 408 include coupling members 438 that interact with corresponding coupling members of the second frame 332 to secure the first frame 330 with respect to the second frame 332. In the illustrated embodiment, the coupling members 438 constitute openings extending through the bridges 408. The openings receive posts or other types of coupling members therein. Other types of coupling members 438 may be provided on the bridges 408, such as posts, slots, latches, or other types of fasteners.
In an exemplary embodiment, the first frame 330 includes dielectric inserts 440 extending from one or more of the frame members 400. The dielectric inserts 440 are integral with the frame members 400. The dielectric inserts 440 are co-molded with the frame members 400. The dielectric inserts 440 are molded at the same time as the frame members 400 and extend outward from corresponding edges 442 of the frame members 400. The dielectric inserts 440 are configured to fill the windows or voids left in the second frame 332 (shown in
The frame members 400 include voids or windows 444 left behind when the removable inserts 370 (shown in
The frame members 450 extend between a mating end 454 of the second frame 332 and a mounting end 456 of the second frame 332. In the illustrated embodiment, the mating end 454 is generally perpendicular with respect to the mounting end 456; however other orientations are possible in alternative embodiments. The receptacle signal contacts 162 extend from the frame members 450 beyond the mating end 454 and beyond the mounting end 456 for electrical termination to other components, such as the second header assembly 118 and the second circuit board 150 (both shown in
The frame members 450 are connected by bridges 458 that span the gaps 452. The bridges 458 position the frame members 450 with respect to one another. In an exemplary embodiment, the bridges 458 are located proximate to the mating end 454 and the mounting end 456 of the second frame 332. The bridges 458 are co-molded with the frame members 450. The bridges 458 define flow paths for the dielectric material of the frame members 450 during the molding (e.g. injection molding) process. For example, the dielectric material may be injected into the mold at gating points (generally identified at points GP) which are located along the outer-most frame member 450 and the dielectric material flows through the bridges 458 into the interior frame members 450 to mold the entire frame 332. Any number of gating points may be provided. The gating points GP may be located on interior frame members 450 in addition to, or in lieu of, the outer frame member 450. The force from the injection of the dielectric material at the gating points may cause pressure and shifting of the receptacle signal contacts 162 of the leadframe. The removable inserts 370 (shown in
In an exemplary embodiment, the second frame 332 includes a leadframe, similar to the leadframe 360 (shown in
The frame members 450 include locating posts 480 extending therefrom. The locating posts 480 are configured to be received in corresponding openings in the conductive holder 310 (shown in
In an exemplary embodiment, at least some of the frame members 450 include troughs 484. The troughs 484 are recessed areas that are configured to receive portions of the first frame 330 (shown in
In an exemplary embodiment, the bridges 458 include coupling members 488 that interact with corresponding coupling members of the first frame 330 to secure the first frame 330 with respect to the second frame 332. In the illustrated embodiment, the coupling members 488 constitute openings extending through the bridges 458. The openings receive posts or other types of coupling members therein. Other types of coupling members 488 may be provided on the bridges 458, such as posts, slots, latches, or other types of fasteners.
In an exemplary embodiment, the second frame 332 includes dielectric inserts 490 extending from one or more of the frame members 450. The dielectric inserts 490 are integral with the frame members 450. The dielectric inserts 490 are co-molded with the frame members 450. The dielectric inserts 490 are molded at the same time as the frame members 450 and extend outward from corresponding edges 492 of the frame members 450. The dielectric inserts 490 are configured to fill the voids or windows 444 left in the first frame 332 (shown in
The frame members 450 include voids or windows 494 left behind when the removable inserts 370 (shown in
When the first and second frames 330, 332 are coupled together, the bridges 408 span across and engage corresponding frame members 450 of the second frame 332. For example, the bridges 408 are received in corresponding troughs 484. Similarly, the bridges 458 (shown in
When the first and second frames 330, 332 are coupled together, the dielectric inserts 440 of the first frame 330 are received in corresponding windows 494 of the second frame 332. The dielectric inserts 440 substantially fill the windows 494. The dielectric inserts 440 cover the receptacle signal contacts 162 to limit exposure of the receptacle signal contacts 162 to air, which has a different dielectric constant than the dielectric material and which would impact or degrade the signal integrity. The dielectric inserts 440 may compensate from air around the signal contacts 162. Covering of the receptacle signal contacts 162 maintains the signal integrity of the receptacle signal contacts 162. Similarly, when the first and second frames 330, 332 are coupled together, the dielectric inserts 490 of the second frame 332 are received in corresponding windows 444 of the first frame 330. The dielectric inserts 490 substantially fill the windows 444. The dielectric inserts 490 cover the receptacle signal contacts 162.
In an exemplary embodiment, the gaps 402, 452 are sufficiently wide to accommodate the corresponding frame members 450, 400. For example, a width of the gaps 402 is wider than a width of the frame members 450. Similarly, a width of the gaps 452 is wider than a width of the frame members 400. In an exemplary embodiment, slots are defined between the frame members 400, 450. Widths of the slots may vary depending on the widths of the gaps and the widths of the frame members 450, 400. In an exemplary embodiment, the slots are sized and shaped to receive the tabs 322, 324 (shown in
Having the first frame 330 manufactured separately from the second frame 332 allows adequate spacing between the receptacle signal contacts 162 for stamping and forming the mating portions 364 of the receptacle signal contacts 162. For example, a dimension of material that is required to form the mating portions 364 may be greater than the desired spacing. In order to have the tight spacing between the receptacle signal contacts 162, the two frames 330, 332 are separately manufactured and coupled together.
An opening 512 is formed in the main wall 502 between the fingers 510. The opening 512 is configured to receive a corresponding post of the second frame 332 (shown in
First and second channels 514, 516 are formed between the fingers 510 and the corresponding end walls 504, 506. The first and second channels 514, 516 receive the receptacle signal contacts 162 (shown in
In an exemplary embodiment, the dielectric inserts 440 include angled side walls 518, 520 extending between the end walls 504, 506. The side walls 518, 520 are narrower at the top and wider at the bottom (or vice versa). The side walls 518, 520 define a wedge shaped piece configured to be plugged into the window 494 in the second frame 332. The angled side walls 518, 520 are aligned with the conductors of the second frame 332 when coupled thereto to provide improved coverage of the conductors, which may improve the signal integrity of the conductors.
The dielectric inserts 440 may have other shapes or features in alternative embodiments. The dielectric inserts 490 (shown in
In an exemplary embodiment, one of the signal contacts 704 closest to, and exterior of, the gating point is held by a removable insert (not shown) during overmolding, thus forming a window 708 around a portion of the signal contact 704 and frame member 706. A dielectric insert 710 is configured to be coupled to the frame 702 at the window 708. The dielectric insert 710 plugs the window to reduce effects of air exposure to the signal contact 704. Optionally, when multiple removable inserts are used to hold different signal contacts 704, thus forming multiple windows, multiple dielectric inserts 710 may be molded together, such as with bridges therebetween, to be coupled to the frame 702 as a single piece.
In an exemplary embodiment, one or more pairs of the signal contacts 804, such as those closest to the gating point, is held by a removable insert (not shown) during overmolding, thus forming a window 808 around a portion of the signal contacts 804 and corresponding frame member 806. A dielectric insert 810 is configured to be coupled to the frame 802 at the window 808. The dielectric insert 810 plugs the window to reduce effects of air exposure to the signal contact 804.
A post 812 (shown in
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. 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.
