Electrical circuit connector with tapered surface

Information

  • Patent Grant
  • 6491543
  • Patent Number
    6,491,543
  • Date Filed
    Thursday, June 22, 2000
    24 years ago
  • Date Issued
    Tuesday, December 10, 2002
    22 years ago
Abstract
An electrical connector includes a electrical connector extending between a pair of mechanical connectors to electrically couple circuits, and a supporting member between the mechanical connectors to reduce twisting of the electrical connector. The supporting member cambered to permit the mechanical connectors to translate with respect to one another. A clamping member includes a tapered clamping surface in an undeformed, unclamped position. The clamping member bends when in a clamped position, resulting in approximately planar clamping surface. Resilient pressure pads on the clamping members bias the electrical connector to the circuit board. The pressure pads are mounted in wells in the clamping members to support a sidewall of the pressure pads. Frames provide additional support to the sidewalls of the pressure pads. The pressure pads include a raised edge along a periphery of a contact surface of the pressure pad. Additionally, or alternatively, a support shoulder in the well cooperates with a recess along a periphery of a mounting surface of the pressure pad to support the sidewall. Alignment structure on the frame cooperates with alignment structure on the clamping members, the printed circuit boards and the electrical connectors to align contacts on the electrical connectors with contacts on the printed circuit boards, and to further align the pressure pads with the contacts.
Description




TECHNICAL FIELD




This invention relates to electrical connectors, and more particularly to an improved socket for electrical connectors coupled to printed circuit boards.




BACKGROUND OF THE INVENTION




Many computing devices, such as desktop computers, workstations, mainframe and super-computers employ multiple printed circuit boards (“PCB”) that include various microprocessors, printed circuits and other components that must be electrically coupled together to transmit data and/or power. The electrical traces on one or more layers of the printed circuit board form the printed circuits and typically terminate in one or more terminals or contacts for making connections. Every decreasing element sizes, such a pitch (i.e., the spacing between successive components), width, and height, exacerbate the problem of providing secure and reliable connections between the printed circuits. Precise positioning on the order of thousandths of an inch is often necessary. Consistent pressure across each of the many contacts is also desirable to assure a reliable connection. A single failed or intermittent connection of a contact on a printed circuit board can result in large amounts of “down-time” for the computing device, and costly troubleshooting by highly skilled technicians.




A reliable, precise, and highly manipulable electrical connector is required to couple printed circuits between printed circuit boards. Additionally the connection should be secure over a time period commiserate with the expected life of the computing device to avoid costly maintenance and should allow easy replacement and/or addition of various computer components such as printed circuit boards.




SUMMARY OF THE INVENTION




According to principles of the invention, a clamping member of an electrical connector is thicker in a central region than in the end region. The clamp includes a bar that is tapered from the center to the edges when in an undeformed state and unclamped position. The bar is deformed under a force applied at the ends as the clamping members are moved into a clamped position. The result is a generally planar clamping surface when the clamping members are in the clamped position.











BRIEF DESCRIPTION OF THE DRAWINGS




In the drawings, identical reference numbers identify similar elements or acts. The sizes and relative positions of elements in the drawings are not necessarily drawn to scale and various elements and portions of elements may be are arbitrarily enlarged and positioned to improve drawing legibility.





FIG. 1

is an isometric view of a clamping assembly and electrical connector according to the present invention.





FIG. 2

is an exploded front, right isometric view of the clamping member of FIG.


1


.





FIG. 3

is a partial, cross-sectional view of the member and resilient pad of

FIG. 2

taken along section lines


3





3


of FIG.


2


.





FIGS. 4A-4D

are a partial, cross-sectional view of an alternative embodiment of the resilient pad of FIG.


3


.





FIG. 5

is a front elevational view of the printed circuit board and electrical connectors received between the clamping members and pressure pads that are undeformed while in an unclamped position.





FIG. 6

is a front elevational view of the printed circuit board and electrical connectors received between the clamping member and pressure pads that are deformed while in the clamped position.





FIG. 7

is a front elevation of an alternative embodiment of the clamping member.





FIG. 8

is a front elevation of a further alternative embodiment of the clamping member.











DETAILED DESCRIPTION OF THE INVENTION




In the following description, certain specific details are set forth in order to provide a thorough understanding of various embodiments of the invention. However, one skilled in the art will understand that the invention may be practiced without these details. In other instances, well-known structures associated with computers, printed circuit boards, circuits and mechanical clamps have not been shown or described in detail to avoid obscuring descriptions of the embodiments of the invention.





FIG. 1

shows a clamping assembly


10


composed of a clamping member


12


, a frame


14


and pressure pads


16


. An electrical connector


18


is shown in position ready for connection to a circuit board by clamping assembly


10


. The clamping member


12


has a first end


20


and a second end


22


and a central portion


24


. According to a preferred embodiment of the present invention, the central portion


24


is somewhat thicker than at the ends


20


and


22


. This will be explained, and shown in more detail, with respect to

FIGS. 5-8

. Posts and collars


26


and


28


are provided at each of the ends


20


,


22


respectively in order to receive and provide alignment with frame


14


.




Frame


14


rests on top of and in alignment with clamping member


12


. The frame


14


includes an electrical connector alignment structure in the form of a set of pins


30


sized and dimensioned to engage a pair of holes


32


in the end of the electrical connector


18


. The pins


30


align a plurality of electrode contacts


46


on an end of the electrical connector


18


with the respective pressure pad


16


. The alignment structure may also include, in an alternative embodiment, horizontal guide bars


34


and


36


on either side of the strip so as to position it in the proper location on the pressure pad


16


. In some embodiments, guide bars


34


and


36


are not used and instead the pressure pad and pins


30


are in a recess to provide alignment. Of course, any acceptable alignment structure can be used, and those shown here are merely given for example to illustrate ways in which the electrical connector


18


can be ensured to have proper alignment on top of the pressure pad


16


to make good electrical contact when the clamping occurs, as shown in

FIGS. 5 and 6

. The alignment structure on the clamping members


12


, frames


14


and electrical connectors


18


cooperate to ensure that the contacts


46


on the electrical connectors


18


precisely align with the contacts


38


(

FIGS. 5 and 6

) on the surfaces of the respective printed circuit boards


40


. Precise alignment is important to providing secure, reliable electrical connections.





FIG. 2

shows an exploded view of the clamping assembly


10


. The clamping member


12


includes a recess


23


into which the pressure pads


16


are positioned. The pads


16


may be held in position by a pressure fit, or by adhesive is desirable, either method being acceptable. The pressure pad


16


includes a raised edge


48


as described in more detail later with respect to

FIGS. 3 and 4

. The clamping member


12


may include a shoulder


19


adjacent each end in order to provide additional alignment with the frame


14


; however, this is an optional alignment structure, and different or additional structures can be used.




The frame


14


is shaped to be positioned on top of and aligned with the clamping member


12


. It contains apertures in each end to align with the posts and collars


26


and


28


of the clamping member as well as a shoulder mating portion to align and mate with the shoulder


19


. Other configurations may also be used to mate and align the frame


14


with the clamping member


12


.




The frame


14


contains apertures


21


that align with and surround pads


16


. The sidewalls of the apertures


21


provide support to the sidewalls of the pad


16


so as to provide a solid surface for even pressure to the electrical contact members


46


. This arrangement of the frame


14


, together with the pad


16


and the clamping member


12


provides for the easy assembly of the clamping assembly


10


as a whole. It also ensures proper and correct alignment of the electrical contacts


46


with the printed circuit boards.




In an alternative embodiment, the frame


14


is not used. Instead, the recesses


23


and the clamping member


12


are made deeper and the pad


16


is positioned within the deep recess to provide support to the sidewalls. In addition, the alignment structures


30


are positioned on the clamping member


12


to align and mate with the apertures


32


of the electrical connectors


18


.




The frame


14


includes on its upper surface raise guides


34


and


36


to provide an additional alignment structure for the electrical connector


18


when it is connected to clamping assembly


10


. When the clamping assembly


10


is fully assembled, it provides reliable alignment, with solid support for the electrical connectors


18


to be positioned thereon for later clamping to provide electrical connection to the printed circuit board


40


.




As shown in

FIG. 3

, each of the pressure pads


16


include a raised edge


48


along a periphery of the upper surface of the pressure pad. The upper surface of the pressure pad


16


contacts the end portion of the electrical connector


18


to bias the contacts


46


of the electrical connector against the contacts


30


(FIGS.


5


and


6


). There is a tendency for the periphery of the resilient pressure pads


16


to sag downward and the sidewalls


49


and


51


bulge outward as the clamping assembly


10


applies pressure to the connector


18


. The raised edge


48


counteracts this tendency and helps to evenly distribute the pressure exerted on the electrical contacts


46


through the pressure pads


16


when the clamp is shut. The frame


14


, and the recess


23


in the clamping member


12


, each support the sides walls


49


and


51


of the pressure pads


16


to also alleviate the tendency for them to bulge. As an alternative, instead of a separate, discrete frame


14


, the frame


14


can be an integral portion of the clamping members


12


, for example an upright edge surrounding each of the recesses


23


, or the recesses


23


could be made deeper.




As shown in

FIG. 3

in a cross-sectional view, the pressure pad


16


fits into recess


23


. The dimensions of the pressure pad


16


are slightly larger than the dimensions of the recess


16


to achieve a press fit of the pressure pad


16


in the recess


16


. The press fit deforms the pressure pad


16


, increasing the rigidity of the pressure pad


16


and reducing the tendency of the sidewalls


49


and


51


of the pressure pad


16


to bulge under pressure. Adhesive can be added if desired to provide rigidity to the mounting in addition to the press fit. The raised edges


48


can be achieve by molding, or by removing material from a center portion of the pressure pad


16


.





FIGS. 4A-4D

show alternative embodiments of the pressure pad


16


and the recess


23


. In

FIG. 4A

, the pressure pad


16


has an approximately planar contacting surface and a shoulder


52


formed along a peripheral edge of contacting surface


114


the pressure pad


16


. The shoulder


52


extends around the periphery, and beyond the outer edge of the contact area


114


for the electrical contacts


46


. The shoulder


52


thus provides additional lateral support for the upper surface so as to prevent the bulging of the sidewalls and retain the upper surface in a generally planar configuration during clamping. The recess


23


includes a support surface


54


for the pressure pad


16


about the periphery of the mounting surface. The shape of the shoulder


52


conforms to the shape of the recess


23


in the clamping member


12


. The support shoulder


52


assists in countering the tendency of the sidewalls


51


and


49


of the pressure pad


112


to bulge under pressure. The pressure pad


112


is again press fit into the recess


23


.





FIGS. 4B-4D

illustrate further alternative embodiments of the pressure pad


16


according to principles of the present invention. The pad


16


includes a central member


150


composed of a first material and a second material


148


that is connected along the sidewalls of the material


150


. Both of the materials,


150


and


148


, can be a rubber or other deformable member. However, the material


148


is slightly more firm than the material used for


150


. For example, the material


148


may be a somewhat harder rubber, or have a more firm response because it is a stiffer elastomeric member than the central portion


150


. Having the pressure pad


16


composed of a two-part material also provides the advantage that when pressure is applied to the upper surface


114


, the pad


16


will remain flat and uniform across this entire surface and provide an even support across the entire upper surface


114


so as to provide solid electrical contact of all pads


46


.





FIG. 4C

is a cross-sectional view taken along lines


4




c





4




c


of

FIG. 4



b


to illustrate the two materials


150


and


158


which comprise the pad


16


. The outer layer


148


can be a sleeve into which the pad


150


is placed. In this embodiment, the pad


150


is slightly larger than the aperture in sleeve


148


so that the pad is compressed and held firmly in position.





FIG. 4D

is a further alternative embodiment of pressure pad


16


in which the material


148


is like a box having a bottom as well as on the sidewall. This embodiment can be used to provide firm support inside the recess


23


and may be used in place of, or in addition to, an adhesive. The material


148


may also be of the type which works better with the adhesive than the material


150


and thus provides a good contacting surface for bonding the pad


16


to the clamp


12


.




As previously stated

FIGS. 4B-4D

show an alternative embodiment of the resilient pressure pad


112


, including a pressure pad sleeve


148


receiving a pressure pad core


150


. The pressure pad sleeve


148


has a durometer value greater than a durometer value of the pressure pad core


150


. The pressure pad sleeve


148


has an aperture


152


having dimensions slightly smaller than corresponding dimensions of the pressure pad core


150


, to receive the pressure pad core


150


in a press fit. Thus, the pressure pad sleeve


148


supports the sidewall


154


of the pressure pad core


150


. As seen in

FIG. 4C

, the aperture


152


can extend completely through the pressure pad sleeve


148


, or can extend only partially through the pressure pad sleeve


148


as shown in FIG.


15


. The contacting surface


114


of the pressure pad core


150


is disposed over the contacts


46


on the end portion


48


of the electrical connector


18


to ensure that constant pressure is applied across the contacts


46


. The pressure pad sleeve


148


does not directly over any of the contacts


46


, and so does not directly apply force to the contacts


46


. The pressure pad sleeve can be mounted to the clamping surface


70


, or within the wells


108


of the clamping members


58


,


60


.





FIG. 5

shows two clamping members


12


and the pressure pads


10


undeformed, while the clamping members


12


are in the unclamped position. The frames


14


are not shown to improve the legibility of the drawing. The clamping surface


70


of the clamping member is tapered from a centerline


142


, out toward the ends


20


and


22


of the clamping member


12


. For example, a taper producing an angle θ of approximately 0.573 degrees may be sufficient. Tapers in the ranges of 0.1 to 2.0 degrees may be used. (The taper is not shown to scale in the figure, but shown enlarged for purposes of illustration.) Hence, the space between the clamping members


12


and board


40


increases towards the ends


20


and


22


near clamping bars


43


and


45


. Similarly, the space between the electrical connectors


18


on pressure pads


16


and contacts


38


increases towards the ends


20


and


24


along the length of the clamping member


12


in anticipation of the bending of the clamping members


12


when they are to be clamped. As can be appreciated, when rods


43


and


45


apply force to hold the clamp


12


solid against the printed board


40


, the force will be applied mostly at the end portions


20


and


22


, thus deforming the bar


12


. It is desirable to ensure that all electrical contacts between the connector


18


via contact points


46


and the printed circuit board


40


having contact electrodes


38


are precisely made, with uniform pressure applied to all contacts.




Accordingly, the principle of the present invention provides uniform pressure when clamped of all electrical connectors


18


of electrodes


46


to electrodes


38


by ensuring that even pressure is provided along the entire length of the bar


12


even though it is clamped at both ends. The pressure pads


16


are also configured to provide even pressure across the entire surface of the pad for each of the electrical contacts


46


when in the clamped position. As shown in

FIG. 5

, the pressure pads


16


have a slight upstanding ridge


48


around the edge portions, also as shown in the embodiment of FIG.


3


. Once the clamps


12


are pressed firmly against the circuit board


40


, the pressure pads


16


will be deformed to be uniformly flat across their entire surface and in addition the clamping members


12


will be uniformly flat along the surface which is presented to the printed circuit board


40


, as shown in FIG.


6


.





FIG. 6

shows the clamping members


12


of

FIG. 5

, with the clamping member


58


in a clamped position


6


n circuit board


40


. The taper in the clamping member


12


accommodates the bending of the clamping member


12


to produce an approximately planer clamping surface


70


when the clamping member


12


is in the clamped position. Hence, each of the pressure pads


16


exert a uniform pressure on their respective electrical connectors


18


and printed circuit boards


40


.




As can be seen by

FIG. 6

, when the force is applied through clamping rods


43


and


45


to the end portions


20


and


22


, respectively, the member


12


is brought into flat alignment with the printed circuit board


40


and the clamping surface


70


becomes uniformly flat across its entire surface. The clamp member


12


bulges out slightly on a back surface as it is clamped at both ends. This provides even and steady pressure to the rubber pad


16


in supporting the electrical connectors


18


and contact between electrodes


38


and


46


without such uniform pressure, some of the contacts


46


and


38


may not be touched to each other, creating an electrical open circuit.




In addition to the slight deformation of the clamping member


12


, the pads


16


also undergo a slight deformation along their edge surfaces. The upstanding edge


48


is slightly depressed by the edge portions of the electrical circuit board


18


. Those electrical connectors


46


which are on the outermost edges of the electrical connector


18


are provided the same support and even pressure as those at the center portion of the pad


16


. Thus, uniformly flat, and even pressure contact surface


114


is provided to the electrical connectors


46


and


38


to hold them in contact with each other for an extended period of time.




The design of the present invention has the advantage that solid electrical contact is assured over long periods of time with high reliability. Over time, the metal, as well as the rubber, may fatigue slightly. The design of the present invention takes such fatigue into account so as to ensure that even pressure is applied over the life of the electrical connection. In addition, in the event that the electrical connectors are to be removed, the clamp member


12


can be easily removed and appropriate adjustments made and then reconnected with a high degree of assurance that even pressure will be applied to all electrical connectors


46


and


38


without loss of connection.





FIGS. 7 and 8

illustrate alternative members of the clamp


12


which may be used according to principles of the present invention. The clamp


12


of

FIG. 7

tapers from the center portion outward along both surfaces so as to be somewhat thinner in the portions


20


and


22


both on the top surface and on a bottom surface. The central portion


24


thus has a bulge on both the top and bottom, as can be seen in the exaggerated FIG.


7


.

FIG. 5

is an alternative embodiment in which a bulge


25


occurs only along the top surface. In this instance, the bottom surface


27


is generally flat between end regions


20


and


22


and does not have a taper or other additional material thereon. The upper surface, which becomes the clamping surface


70


, however, does include a bulge


25


so that the clamping member


12


is slightly thicker at the central region


24


than at the ends


20


and


22


. In this alternative embodiment, the taper to create the bulge


25


may be somewhat larger than that which is used for the taper as shown in

FIG. 5

, since it is only a single surface that is tapered and not both surfaces. The amount of taper for the bar


12


will of course depend on the amount of force used in clamping the bar as well as the anticipated deformation of the bar under clamping, as can be easily calculated based on the design of each individual clamping member


12


. Accordingly, the amount of taper used in each of the embodiments, for

FIGS. 5-8

, will be based on the taper needed to present a uniformly flat and even pressure clamping surface


70


once the clamping member


12


is connected to the board


40


to provide electrical contact.





FIG. 8

shows a further alternative embodiment according to principals of the present invention. In this embodiment, the clamping member


12


has a uniform thickness from one end


20


to the other end


22


. However, the central portion is arched slightly upward so as to present a slightly increased pressure in the central region. Thus, the upper surface


70


which becomes the clamping surface has a slight arch


27


between the ends, and this arch is exactly the same radius as the arch


29


from the bottom surface


27


so even though the clamping member has a uniform thickness between


20


and


22


, it will provide additional pressure in the central regions so as to have uniform pressure across this entire length when in the clamped position.




Although specific embodiments of and examples for, the invention are described herein for illustrative purposes, various equivalent modifications can be made without departing from the spirit and scope of the invention, as will be recognized by those skilled in the relevant art. The teachings provided herein of the invention can be applied to other electrical connectors, not necessarily the exemplary clamping electrical connector generally described above.




The various embodiments described above can be combined to provide further embodiments. All of the above U.S. patents, patent applications and, publications referred to in this specification are incorporated by reference. Aspects of the invention can be modified, if necessary, to employ systems, circuits and concepts of the various patents, applications and publications to provide yet further embodiments of the invention.




These and other changes can be made to the invention in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the invention to the specific embodiments disclosed in the specification and the claims, but should be construed to include all connectors and clamping devices that operate in accordance with the claims. Accordingly, the invention is not limited by the disclosure, but instead its scope is to be determined entirely by the following claims.



Claims
  • 1. A circuit board connector, comprising:an elongated first clamping member having a first alignment structure, a first and a second opposed ends and a first clamping surface; an elongated second clamping member having a second alignment structure, first and second opposed ends and a second clamping surface generally facing the first clamping surface of the first clamping member where the first and the second clamping members are movable with respect to one another between a clamped position to secure a flexible circuit path to a circuit board and an unclamped position spaced from the clamped position, at least one of the first and the second clamping surfaces having a rise toward a middle point between the first and the second opposed ends thereof when the clamping members are in the unclamped position; a first frame having a clamping member alignment structure sized and dimensioned to mate with the first alignment structure; and a second frame having a clamping member alignment structure sized and dimensioned to mate with the second alignment structure.
  • 2. The circuit board connector of claim 1 wherein both the first and the second clamping surfaces have a rise toward the middle point between the first and the second opposed ends thereof when the clamping members are in the unclamped position.
  • 3. The circuit board connector of claim 1 wherein the at least one of the first and the second clamping surfaces having the rise toward the middle point when the first and the second clamping members are in the unclamped position is approximately planar when the first and the second clamping members are in the clamped position.
  • 4. The circuit board connector of claim 1, further comprising:a plurality of resilient pressure pads on the first clamping member.
  • 5. The circuit board connector of claim 1, further comprising:a plurality of resilient pressure pads partially located in a respective recess formed on the first clamping member.
  • 6. The circuit board connector of claim 1 wherein the first and the second clamping members each include at least one threaded hole at each of a first and a second opposed ends thereof, and further comprising:a first threaded clamp adjustment member engaging the threaded holes at the first end of each of the first and the second clamping members; and a second threaded clamp adjustment member engaging the threaded holes at the second end of each of the first and the second clamping members.
  • 7. A clamp to electrically couple printed circuits, comprising:a first clamping member having a first clamping surface and a thickness, and wherein the thickness of the first clamping member at a point between first and second ends thereof is greater than the thickness of the first clamping member at the first or second ends; a second clamping member having a second clamping surface generally facing the first clamping surface; and at least a first threaded adjustment member engaging the first and the second clamping members to move the first and the second clamping members with respect to one another between a clamped position where the first and the second clamping members are spaced relatively closely together and an unclamped position where the first and the second clamping members are spaced relatively apart, and where a distance between the first and the second clamping surfaces varies along a length of the first clamping surface when the first and the second clamping members are in the unclamped position, and wherein the distance between the first and the second clamping surface does not vary along the length of the first clamping surface when the first and the second clamping members are in the clamped position.
  • 8. The clamp of claim 7 wherein a thickness of the second clamping member tapers along the length thereof from a point between first and second ends toward each of the first and the second ends.
  • 9. The clamp of claim 7, further comprising:a number of resilient pressure pads on at least one of the first and the second clamping surfaces.
  • 10. The clamp of claim 7, further comprising:a number of resilient pressure pads on the first clamping member; a number of resilient pressure pads on the second clamping member; a first frame received between the first and the second clamping surfaces, the first frame having a respective opening for each of the pressure pads on the first clamping members, the openings sized and dimensioned to receive a respective one of the pressure pads on the first clamping member; and a second frame received between the first and the second clamping surfaces, the second frame having a respective opening for each of the pressure pads on the second clamping member, the openings sized and dimensioned to receive a respective one of the pressure pads on the second clamping member.
  • 11. The clamp of claim 7, wherein the first clamping member includes an integral frame extending from the first clamping surface toward the second clamping surface, the frame being adjacent at least a first sidewall of a first resilient pressure pad.
  • 12. The clamp of claim 7, further comprising:a first frame received between the first and the second clamping surfaces, the first frame having a clamping member alignment structure to mate with an alignment structure on the first one of the clamping members and a flexible circuit path alignment structure to mate with an alignment structure on a first flexible circuit path; and a second frame received between the first and the second clamping surfaces, the second frame having a clamping member alignment structure to mate with an alignment structure on the second one of the clamping members and a flexible circuit path alignment structure to mate with an alignment structure on a second flexible circuit path.
  • 13. The clamp of claim 12 wherein the flexible circuit path alignment structure on the first and second frames each include a number of pairs of pins and a number of pairs of openings, each of the pairs of pins aligned with a respective one of the pairs of openings on the frame, the pins sized to be received by holes formed in a substrate of a flexible circuit path.
  • 14. A clamp for electrically coupling printed circuits, comprising:a pair of opposed clamping members, the clamping members movable with respect to one another between a clamped position and an unclamped position spaced from the clamped position; at least one nonconductive resilient pressure pad secured to at least one of the clamping members; and a first frame received between the opposed clamping members and having a respective opening for each of the pressure pads on a first one of the clamping members, the openings sized and dimensioned to receive the respective one of the pressure pads.
  • 15. The clamp of claim 14 wherein the size of the openings is less than a size of the respective pressure pads, the openings receiving the pressure pads in a press fit.
  • 16. The clamp of claim 14 wherein the first frame includes a clamping member alignment structure to mate with an alignment structure on a first one of the opposed clamping members.
  • 17. The clamp of claim 14 wherein the first frame includes a flexible circuit path alignment structure to mate with an alignment structure on a first flexible electric circuit path.
  • 18. The clamp of claim 14 wherein the frame is an elongated metal plate.
  • 19. The clamp of claim 14, further comprising.a second frame received between the first frame and a second one of the clamping members, the second frame having a respective opening for each of a number of the pressure pads on the second clamping member, the openings sized and dimensioned to receive the respective one of the pressure pads, the second frame having a clamping member alignment structure to mate with an alignment structure on the second one of the clamping members and a flexible circuit path alignment structure to mate with an alignment structure on a second flexible electric circuit path.
  • 20. A clamp for electrically coupling printed circuits, comprising:a first clamping member; a second clamping member opposed to the first clamping member and moveable with respect thereto between a clamped position and an unclamped position; a first set of resilient pressure pads secured to the first clamping member; a second set of resilient pressure pads secured to the second clamping member; a first frame received between the first and the second clamping members, the first frame having a respective opening for each of the pressure pads in the first set of pressure pads, the openings sized and dimensioned to receive the respective one of the pressure pads; and a second frame received between the second clamping member and the first frame, the second frame having a respective opening for each of the pressure pads in the second set of pressure pads, the openings sized and dimensioned to receive the respective one of the pressure pads.
  • 21. The clamp of claim 20 wherein the size of the openings in the first and the second frames is less than a size of the respective pressure pads, each of the openings receiving the respective pressure pad in a press fit.
  • 22. The clamp of claim 20 wherein the first frame includes a flexible circuit path alignment structure including a pair of posts for each of the openings to mate with an alignment structure on a flexible electric circuit path including a pair of holes in the flexible electric circuit path positioned and sized receive the posts to align a set of contacts on the flexible electric circuit path in the opening of the frame.
  • 23. The clamp of claim 20 wherein the first frame includes a clamping member alignment structure to mate with an alignment structure on a first one of the clamping members, and a flexible circuit path alignment structure to mate with an alignment structure on a flexible electric circuit path.
  • 24. A clamp for electrically coupling printed circuits, comprising:a first clamping member; a second clamping member opposed to the first clamping member and movable with respect thereto between a clamped position and an unclamped position spaced from the clamped position; and at least a first resilient pressure pad having a contacting surface and a raised edge along a periphery of the contacting surface, the first resilient pressure pad secured to the first clamping member for movement therewith such that the contacting surface of the first pressure pad generally faces the second clamping member, the contacting surface positioned to bias a flexible electric circuit path into contact with a circuit board in the clamped position.
  • 25. The clamp of claim 24 wherein the raised edge extends along an entire length of the periphery of the contacting surface.
  • 26. The clamp of claim 24 wherein the raised edge has a uniform height and a uniform width along an entire length of the periphery of the contacting surface.
  • 27. The clamp of claim 24 wherein the first resilient pressure pad is mounted in a first recess formed in the first clamping member, the contacting surface of the first resilient pressure pad extending from the first recess.
  • 28. The clamp of claim 24, further comprising:a frame positioned between the first and the second clamping members, the frame having at least a first opening, the first resilient pressure pad press fit through the first opening.
  • 29. The clamp of claim 24, further comprising:a frame positioned between the first and the second clamping members, the frame having at least a first opening, a portion of the first resilient pressure pad including the contacting surface extending through the first opening, the frame further having a clamping member alignment structure to mate with an alignment structure on the first clamping member, and having a flexible electric circuit path alignment structure to mate with an alignment structure on the flexible electric circuit path.
  • 30. The clamp according to claim 24 wherein the pressure pad comprises:a pressure pad sleeve having a first durometer value and an aperture; and a resilient pressure pad core received in the aperture of the pressure pad sleeve such that a contact surface of the pressure pad core is exposed, the pressure pad core having a second durometer value less than the first durometer value of the pressure pad sleeve.
  • 31. The clamp of claim 30 wherein the pressure pad core is in press fit contact with the pressure pad sleeve.
  • 32. The clamp of claim 30 wherein the aperture extends through the pressure pad sleeve.
  • 33. A printed circuit connector, comprising:a clamping member having a first end, a second end and a middle region and having a first surface and a second surface and a thickness extending from the first surface to the second surface, the thickness at the middle region being greater than the thickness at the first and second ends and configured to bias a lower surface of a first printed circuit against an upper surface of a second printed circuit; and a plurality of fasteners for clamping the first and second ends to a selected surface, providing thereby a force for the biasing.
  • 34. The printed circuit connector of claim 33, further comprising a resilient member interposed between the first surface of the clamping member and an upper surface of the first printed circuit, the resilient member configured to receive a biasing force from the first clamping member and transmit the biasing force to the first printed circuit, and further configured to distribute, by virtue of its resiliency, the biasing force evenly across a contact region of the first printed circuit.
  • 35. The printed circuit connector of claim 33 wherein the clamping member is a first clamping member and the selected surface is a second clamping member configured to bias an upper surface of a third printed circuit against a lower surface of the second printed circuit.
  • 36. The printed circuit connector of claim 35, further comprising:a first resilient member interposed between the first surface of the first clamping member and an upper surface of the first printed circuit, the first resilient member configured to receive a first biasing force from the first clamping member and transmit the first biasing force to the first printed circuit, and further configured to distribute, by virtue of its resiliency, the first biasing force evenly across a contact portion of the first printed circuit; and a second resilient member interposed between the second clamping member and a lower surface of the third printed circuit, the second resilient member configured to receive a second biasing force from the second clamping member and transmit the second biasing force to the third printed circuit, and further configured to distribute, by virtue of its resiliency, the second biasing force evenly across a contact portion of the third printed circuit.
  • 37. A circuit connector, comprising:a first clamping bar; a second clamping bar, the first and second clamping bars configured to bias a plurality of flexible circuits, each including an own plurality of contact pads, against a first surface of a printed circuit board; a plurality of fasteners configured to draw the first and second clamping bars together; and a plurality of resilient pads, each of the plurality of pads being positioned on a first surface of the first clamping bar such that biasing force exerted by the first clamping bar is distributed by the plurality of pads to bias each of the own plurality of contact pads on each of the plurality of flexible circuits against a corresponding one of a plurality of printed circuit contacts on the first surface of the printed circuit board.
  • 38. The circuit connector of claim 37 wherein:the plurality of resilient pads is a first plurality of resilient pads; the plurality of circuits is a first plurality of flexible circuits; the plurality of printed circuit contacts is a first plurality of printed circuit contacts; the first and second clamping bars are further configured to bias a second plurality of flexible circuits, each including an own plurality of contact pads, against a second surface of the printed circuit board; the circuit connector further comprises a second plurality of resilient pads, each of the second plurality of pads being positioned on a first surface of the second clamping bar such that biasing force exerted by the second clamping bar is distributed by the second plurality of pads to bias each of the own plurality of contact pads on each of the second plurality of flexible circuits against a corresponding one of a second plurality of printed circuit contacts on the second surface of the printed circuit board.
  • 39. The circuit connector of claim 38, wherein each of the first and second pluralities of resilient pads fits into a corresponding one of a plurality of depressions in the first surface of the first or second clamping bars.
  • 40. A circuit connector comprising:a clamping bar configured to bias a lower surface of a flexible circuit, having a plurality of contacts, against an upper surface of a printed circuit board, having a corresponding plurality of printed circuit contacts; a resilient member having an upper surface configured to contact a lower surface of the clamping bar and a lower surface configured to contact an upper surface of the flexible circuit and configured to transmit a biasing force from the clamping bar to the printed circuit, the resilient member being sized and shaped such that the lower surface of the resilient member covers an area on an upper surface of the flexible circuit opposite the plurality of contacts on the lower surface of the flexible circuit, the lower surface of the resilient member having a raised edge around a perimeter of the lower surface, the raised edge configured to compensate for a tendency of the resilient member to bulge around the perimeter when biasing force is applied by the first clamping bar, providing thereby an equal biasing force on each of the plurality of contacts.
  • 41. The circuit connector of claim 40 wherein:the flexible circuit is one of a plurality of flexible circuits; The clamping bar is configured to bias a lower surface of each of the plurality of flexible circuits against an upper surface of the printed circuit board; the resilient member is one of a plurality of resilient members, each having an upper surface configured to contact the lower surface of the clamping bar and a lower surface configured to contact an upper surface of one of a plurality of flexible circuits; and each of the resilient members is configured to transmit a biasing force from the clamping bar to a corresponding one of the plurality of flexible circuits.
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Entry
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