Alignment mechanism for a high density electrical connector

Information

  • Patent Grant
  • 6368146
  • Patent Number
    6,368,146
  • Date Filed
    Tuesday, January 16, 2001
    23 years ago
  • Date Issued
    Tuesday, April 9, 2002
    22 years ago
  • Inventors
  • Examiners
    • Luebke; Renee
    • Hammond; Briggitte R.
    Agents
    • Knobbe, Martens, Olson & Bear, LLP
Abstract
A electrical connector suitable for aligning and connecting a high-density wire bundle to a receiving member. The wire bundle is attached to an adapter positioned within a mounting location containing electronically controlled, adjustable pushrods which are used to make the fine lateral and rotational adjustments to the adapter. A control unit detects the position of the adapter within the mounting location and makes fine adjustments to the adapter position as necessary to insure proper alignment and contact.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




This invention relates to the field of electrical connectors and, in particular to a mechanism for aligning an electrical connector such as a coupling for a printed circuit board (PCB) and another electronic component. Specifically, this invention is an alignment mechanism having a sensing device and alignment mechanism which automatically position the electrical connector.




2. Description of the Related Art




In the design of many electronic circuits and components, factors such as space savings and connection integrity are pivotally important. High-density electrical connectors are typically used in a number of electronic applications to conductively join components which contain numerous discrete paths of conductivity to be precisely aligned and joined while maintaining a small connector size. High-density electrical connectors are typically used in the interconnection between packaged integrated circuits (PIC) and printed circuit boards (PCB). In these devices, permanent attachment of one component to another by methods such as soldering may not be desirable due to the inflexibility of the solder connections which are prone to breakage under stress. Furthermore, permanent attachment precludes the desirable ability to disconnect the two components as needed.




Still other applications of high-density electrical connectors can be found in wiring applications where cable, ribbon, or wire bundle arrangements are used to interconnect components within electronic devices which may not be suitable for direct attachment to each other. These wiring arrangements and connectors are likewise configured to be removably attached to one or more of the components which they interconnect. In both of the abovementioned applications, the high-density electrical connector possesses a large number of discrete conductors which must be properly oriented and securely positioned so as to insure connection integrity between the components to be joined.




Conventional pin/socket or plug/receptacle arrangements which are manually positioned, oriented, and joined to provide connectivity between electronic components are inadequate for use in many high-density conductor applications. These connectors are cumbersome to work with and are prone to interconnect failure, breakage, and short-circuiting because of the close proximity of the contacts and fine control over positioning required to achieve sufficient conductivity along all contact points. Furthermore, such connectors are often not suitable for use in applications requiring repeated coupling/uncoupling of the connector and may rapidly become worn resulting in reduced connection efficacy.




In an effort to improve reliability in high-density connection arrangements, various types of connectors have been developed to use thermally responsive electrical elements which employ shape metal alloys (SMA) to secure or release the connector. Using the SMA property of heat induced phase transformation, these connectors typically operate by securing or releasing the connector based on electrical current flow through the alloy. SMA actuated clamps and fasteners for electronic devices have been described for high-density electrical applications and may provide a reversible locking mechanism. Such devices, however, are still subject to the inherent problems of component movement and connection failure should the connection interface be improperly oriented or misaligned. Furthermore, SMA connectors described in the prior art do not provide precise control over the positioning and orientation of the connector interface and suffer from alignment problems associated with manual positioning and attachment. Thus, it is difficult to achieve satisfactory connectivity in high-density connector applications using existing SMA connectors. Additionally, these devices lack a suitable method for detecting the position of the connector which, if known, can be helpful in determining what corrections should be made to the connector position to achieve proper connectivity. These problems are exacerbated in high-density electrical connection applications due to the relatively small size of the connector and the number of contacts which must be made.




From the foregoing, it can be appreciated that there is an ongoing need for a device and method for providing connectivity between electronic components using high-density connection arrangements. Accordingly, there is a need for a device capable of detecting the orientation of a component with a high-density pattern of contacts and making fine adjustments as needed to achieve connection integrity.




SUMMARY OF THE INVENTION




The aforementioned needs are satisfied by the present invention, which in one aspect comprises a high-density electrical connector. The connector comprises a first connector member with a first and second side with a plurality of electrical conductors connected to the first side. A first contact pattern comprising a first plurality of electrical contacts is further defined on the second side of the connector with the electrical contacts connected to the corresponding electrical conductors. The connector allows many electrical conductors to be oriented and positioned in a simultaneous manner using a simplified connector interface. A benefit derived from use of the connector resides in the reduced difficulty in deciphering proper wiring arrangements and conductor orientations. A further benefit of the connector stems from the ability to fashion the connector to occupy a reduced amount of space compared to the amount of space used by traditional electrical connectors.




In the illustrated embodiments, the conductors may comprise wires, cables, or extend from a packaged integrated circuit assembly to be desirably conductively joined to a mounting location or receptacle. The mounting location is further formed on a second connector member having a first surface with a corresponding second contact pattern comprising a second plurality of electrical contacts.




An alignment mechanism engages with the first connector member and the second connector member to precisely align the contact patterns using a sensor assembly and a positioning assembly. The alignment mechanism detects the state of alignment of the connector members through the use of the sensor assembly and further re-positions the connector to insure that the contact patterns of the connector members are desirably conductively joined. In one aspect, the alignment mechanism comprises electronically-actuated pushrod assemblies which generate a bias against the connector sides to align the connector.




Signals generated by the sensor assemblies can be efficiently received and interpreted by a control unit which decodes the current state of alignment of the connector and directs electrical current, corresponding to positioning responses, to the alignment mechanism. The electrical current, received by the alignment mechanism, activates the positioning assembly and alters the bias generated by the pushrod assemblies to result in the lateral and rotational movements of the connector member required to conductively align the contact patterns.




The connector is beneficially used to align high-density contact patterns in an automated manner with an increased degree of precision. The method for precisely aligning the contacts of the contact patterns is initiated by first grossly aligning the contact patterns by positioning the first connector member in proximity to the second connector member. The connector then electrically senses whether the first and second connector members are precisely aligned and electrically induces movement between the connector members in response to the electrical sensing of whether the connector members are aligned.




These and other advantages and features of the present invention will become more fully apparent from the following description and appended claims taken in conjunction with the accompanying drawings.











BRIEF DESCRIPTION OF THE DRAWINGS





FIG. 1A

is a perspective view of a high-density cable and position adapter according to the invention;





FIG. 1B

is a perspective view of a packaged integrated circuit adapter according to the invention;





FIG. 2A

is a perspective view of the high-density cable and pattern adapter illustrating the second surface and a first contact pattern of the pattern adapter;





FIG. 2B

is a perspective view of the packaged integrated circuit adapter illustrating the second surface and a first contact pattern of the pattern adapter;





FIG. 3A

is a perspective view of one embodiment of the mounting location having pushrod assemblies located along recess sidewalls;





FIG. 3B

is a perspective view of another embodiment of the mounting location having pushrod assemblies co-planarly located with a second contact pattern;





FIG. 4A

is a perspective view of the high-density cable and pattern adapter showing the operation of the pushrod assemblies;





FIG. 4B

is a perspective view of the packaged integrated circuit adapter showing the operation of the pushrod assemblies;





FIG. 5

is a cutaway view of the high-density cable and pattern adapter showing the operation of the pushrod assemblies;





FIGS. 6A and 6B

are illustrate of the moveable positioning of the pattern adapter in lateral and rotational directions by the pushrod assemblies;





FIG. 7A

illustrates one embodiment of the present invention for correcting a misaligned contact pattern and sensors;





FIG. 7B

illustrates one embodiment of the present invention showing the properly aligned contact pattern and sensors;





FIG. 8A

illustrates one embodiment of the present invention showing a pattern of sensing contacts on the pattern adapter;





FIGS. 8B and 8C

illustrate the state tables used by the control unit to decode the position of the pattern adapter and issue re-positioning commands based on the pattern shown in

FIG. 8A

;





FIG. 9A

illustrate another embodiment of the present invention showing a pattern of sensing contacts on the pattern adapter; and





FIGS. 9B and 9C

illustrate the state tables used by the control unit to decode the position of the pattern adapter and issue re-positioning commands based on the pattern shown in FIG.


9


A.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT




Reference will now be made to the drawings wherein like numerals refer to like parts throughout.

FIG. 1A

illustrates a perspective view of a high-density electrical connector


90


, comprising a wiring array or conductor cable


100


, attached to a first connector member


93


. In the illustrated embodiment, the first connector member


93


comprises a pattern adapter


102


which secures a plurality of wires


104


(comprising the high-density wiring array or cable


100


) wherein all of the wires


104


are aligned in a simultaneous manner by movement of the pattern adapter


102


through various spatial positions and orientations. The wires


104


of the conductor cable


100


may further comprise multiple types and sizes (gauges) of wire which, by way of example, may include; coaxial wire, shielded wire, unshielded wire, solid wire, stranded wire, insulated wire, uninsulated wire, and optical fiber. In one aspect, the wire ends


106


are affixed to the pattern adapter


102


in a conductively isolated manner so as to allow discrete signals or currents to be conducted through the wires


104


and pattern adapter


102


.




In one aspect, the pattern adapter


102


further comprises a substantially rectangular structure having a first


110


and second


112


surface and side surfaces


114


. Additionally, in the illustrated embodiment, the pattern adapter


102


contains a plurality of centrally disposed embedded channels


116


permitting the passage of the wires


104


through the pattern adapter


102


. Each channel


116


extends from the first surface


110


in a throughgoing path to the second surface


112


of the pattern adapter


102


. The material from which the pattern adapter


102


is constructed allows closely arranged channels


116


to be formed to accommodate the tightly packed arrangement of wires


104


of the conductor cable


100


. A number of materials are suitable for construction of the pattern adapter


102


and may include, for example: plastic, nylon, epoxy, and metal, among other materials. In one aspect, the pattern adapter surfaces


110


,


112


are further dimensioned to contain an area approximately equivalent to the cross sectional area of wire array or conductor cable


100


to which the pattern adapter


102


is attached. Additionally, the pattern adapter


102


desirably accommodates the conductive joining of a wire or cable density between approximately 100 wires or cables per cm


2


and 1600 wires or cables per cm


2


.




In one aspect, the channels


116


of the pattern adapter


102


comprise openings through which individual wires


104


may pass. When passed through the channel


116


, each wire


104


may be further secured in position by adhesive bonding, solder or welding forming a first plurality of electrical contacts


118


(

FIG. 2A

) present on the second surface


112


of the pattern adapter


102


. In another aspect, the channels


116


of the pattern adapter


102


may comprise conductive regions joining the first surface


110


and second surface


112


and wherein the first plurality of contacts


118


are formed along the second surface


112


of the pattern adapter


102


and further conductively joined to the first surface


110


through the channels


116


. In this embodiment, each wire


104


is preferably secured to the first surface


110


of the pattern adapter


102


and further secured to the conductive regions comprising channels


116


by suitable means such as adhesive bonding, solder or welding contacts. Thus, a path of conductivity is made to extend from the wire end


106


secured to the conductive channel


116


on the first surface


110


of the pattern adapter


102


, through the conductive channel


116


of the pattern adapter


102


, to a point where the conductive channel


116


is joined with the electrical contacts


118


which form a first contact pattern


124


present on the second surface


112


of the pattern adapter


102


.




The pattern adapter


102


may further comprise mechanisms for fixedly attaching the pattern adapter


102


on a receiving surface which desirably possesses a second pattern of receiving contacts corresponding to those present on the second surface


112


of the pattern adapter


102


. When the pattern adapter


102


is properly aligned, the mounting mechanisms are secured so as to retain the pattern adapter


102


, and the first contact pattern


124


therein, in a desirable orientation, conductively joining the wires


104


of the high-density electrical connector


100


to a second pattern of contacts of the receiving surface as will be shown in subsequent illustrations. The mounting mechanism for securing the pattern adapter


102


may further include openings or recesses


108


that, for example, may receive attachment devices


109


comprising screws, rods, tabs, latches, epoxy structures or other mounting structures designed to secure the pattern adapter


102


to the mounting location. In another aspect, the pattern adapter


102


may desirably remain unsecured so as to allow the pattern adapter to be continuously aligned, providing a “live” and active positioning method.




In the illustrated embodiment, a rectangularly shaped pattern adapter


102


is shown, however, the pattern adapter


102


can be readily adapted to other shapes and sizes to accommodate additional wiring/cable arrangements and attachment mechanisms which therefore represent additional embodiments and applications as should be appreciated by those of skill in the art.




An additional embodiment of the first connector member


93


is shown in FIG.


1


B. The first connector member


93


forms a pattern adapter


102


from a packaged integrated circuit (PIC) housing, microchip, or other self-contained electronic device. The packaged integrated circuit adapter


91


, comprises similar structural features as the high-density electrical connector


90


(FIG.


1


A). In one aspect, the pattern adapter


102


shown in

FIG. 1B

has a first surface


110


and second surface


112


with side surfaces


114


. Additionally, a first contact pattern


124


is formed along the second surface


112


to allow the electronic components of the PIC to be conductively joined to other components in a manner that will be described in greater detail hereinbelow. As shown in the illustrated embodiment, recesses or openings


108


may be present along the adapter sides


114


and are used to secure the adapter


102


following alignment using a suitable mounting method


111


such as, for example, latches, screws, pins, or epoxy structures.




A perspective view of the pattern adapter


102


further detailing the second surface


112


is illustrated in

FIGS. 2A. A

centrally disposed first contact pattern


124


is formed from numerous/discrete connections to individual wires


104


as previously illustrated. The first contact pattern


124


comprises a plurality of conductive surfaces or contacts


118


, which in one embodiment comprise solder platin or welding points, that are received by a plurality of corresponding receiving contacts as will be shown in detail in later Figures. The illustrated first contact pattern


124


may further comprise large and small contacts


118




a


,


118




b


corresponding to the different sizes and types of wiring


104


. It should be appreciated by those of skill in the art that the illustrated first contact pattern


124


is but one of many possible embodiments and, as such, the first contact pattern


124


can be modified to accommodate any high-density cable array arrangement or wiring scheme without detracting from the spirit of the invention. Furthermore, additional embodiments of the present invention may include other devices or components such as PIC adapters comprising a similar first pattern of contacts


124


to be desirably aligned with a second surface and corresponding contact pattern as shown in FIG.


2


B.




In one aspect, the dimensions of the contact pattern and individual contacts are desirably formed in a high-density arrangement with a density of approximately 100 contacts per cm


2


and 1600 cm


2


. It will be appreciated by those of skill in the art, however, that the pattern of contacts


124


can accommodate higher or lower contact densities and, as such, are considered to be additional embodiments of the present invention.




In both of the abovementioned pattern adapter embodiments, illustrated in

FIGS. 2A

,


2


B, a sensor assembly


95


comprising a plurality of sensing contacts


130


are further arranged about the second surface


112


of the pattern adapter


102


. The sensing contacts


130


comprise conductive surfaces which are disposed within the first contact pattern


124


and are used by the sensor assembly


95


to determine the state of alignment of the pattern adapter


102


in a manner that will be described in greater detail hereinbelow. The size, number, and placement of the sensing contacts


130


on the second surface


112


of the pattern adapter


102


desirably does not occupy a large area increasing the available space for the high-density wiring contacts


118


. The arrangement of sensing contacts


130


further allows for detection of the orientation and position of the pattern adapter


102


when placed in an appropriate mounting location by forming a “bridge” and closing a sensor circuit when the pattern adapter is mounted in a manner that will be described in greater detail in subsequent figures.




A second connector member comprising a mounting location or receptacle


200


, designed to receive and finely adjust the position of the pattern adapter


102


, is illustrated in FIG.


3


A. In the illustrated embodiment, the receptacle


200


comprises a solid member, substantially rectangular in shape, with a rectangular recess


202


centrally disposed within the receptacle


200


. The recess


202


is configured to be sized and shaped to enclose the second surface


112


and sides


114


of the pattern adapter


102


(FIG.


2


). Proper positioning of the pattern adapter


102


commences with the manual placement of the pattern adapter


102


into the recess


202


with the second surface


112


of the pattern adapter


102


resting on a first surface


204


of the receptacle


200


. The area of the recess


202


, defined in part by recess sidewalls


212


, is further configured to have a small amount of space residing between the recess sidewalls


212


and the pattern adapter sides


114


when the pattern adapter


102


is positioned on the receptacle


200


. Furthermore, it will be appreciated by those of skill in the art that the aforementioned recess


202


which houses the pattern adapter


102


may be fashioned using a shallow recess or indentation on the receptacle


200


to partially enclose the second surface


112


and adapter sides


114


.




The space residing between the recess sidewalls


212


and the pattern adapter sides


114


is the result of manufacturing tolerances and permits the pattern adaptor


102


to be positioned within the receptacle


200


in a non-friction manner. Positioning the pattern adaptor


102


within the recess


200


results in the contacts


118


on the adaptor


102


being grossly aligned with a corresponding second plurality of contacts


224


on the first surface


204


of the receptacle


200


. However, as the density of the contacts on the adaptor


102


and on the first surface


204


of the receptacle


200


increase, the spacing between the side walls


114


of the adaptor


102


and the side walls


212


of the receptacle


200


can result in misalignment of the contacts


118


,


224


even though the adaptor


102


is correctly positioned within the receptacle


200


. The alignment mechanism of the illustrated embodiment is, however, specifically adapted to achieve proper alignment of the contacts


118


,


224


following positioning of the adaptor


102


in the receptacle


200


in the manner that will be described in greater detail hereinbelow.




The receptacle


200


additionally contains a plurality of pushrod assemblies


210


positioned about the recess sidewalls


212


and provides a method to moveably position the pattern adapter


102


within the recess


202


. In the illustrated embodiment, the pushrod assemblies


210


are centrally disposed within the recess sidewalls


212


with two pushrod assemblies


210


present on each sidewall.




The first surface


204


of the receptacle


200


, upon which the pattern adapter


102


rests, additionally forms a second contact pattern


206


comprising a second plurality of electrical contacts


224


. The second contact pattern


206


and second electrical contacts


224


are formed to have substantially the same shape and number of contacts as the first contact pattern


124


present on the second surface


112


of pattern adapter


102


. The pattern adapter


102


is properly aligned within the recess


202


of receptacle


200


when the first contact pattern


124


and second contact pattern


206


are in direct and continuous contact and wherein each contact of both the pattern adapter


102


and receptacle


200


are aligned with the corresponding contact of the opposing surface. In one aspect, proper alignment in the aforementioned manner desirably creates discrete paths of conductivity which can be used to join the individual wires


104


of the high-density cable


90


with other electrical components or devices connected to the receptacle


200


.




The second contact pattern


206


additionally comprises a plurality of alignment sensors or probes


208


used to detect the position and orientation of the pattern adapter


102


when inserted into the receptacle


200


. In the illustrated embodiment, alignment sensors


208


are embedded within the second contact pattern


206


in areas unoccupied by the second plurality of electrical contacts


224


. The alignment sensors


208


provide signals to direct the activity of the pushrod assemblies


210


to reposition the pattern adapter


102


, as needed, and align the first contact pattern


124


and the second contact pattern


206


in a manner that will be discussed in subsequent illustrations.




Another embodiment of the second connector member comprising a mounting location or receptacle


200


is shown in FIG.


3


B. In this embodiment, the receptacle


200


comprises a structure wherein the second contact pattern


206


and pushrod assemblies


210


are co-located along a substantially planar surface comprising the first surface


204


of the receptacle


200


. The pattern adapter


102


(

FIG. 2

) is further positioned with its second surface


112


resting on the first surface


204


of the receptacle


200


. As with the previously illustrated receptacle


200


(FIG.


3


A), a recessed area may optionally be present in the receptacle


200


, into which the pattern adapter


102


is placed.




In both of the above-illustrated embodiments shown in

FIGS. 3A

,


3


B the pushrod assemblies


210


located within the mounting location or receptacle


200


moveably position the pattern adapter


102


to desirably achieve an aligned state where the first contact pattern


124


of the pattern adapter


102


is conductively joined and aligned with the second contact pattern


206


of the receptacle in a manner that will be described in greater detail in subsequent Figures and discussion.





FIG. 4A

,


4


B illustrate the placement of the high-density electrical connector


90


and packaged integrated circuit adapter


91


respectively within the receptacle


200


. The following discussion is directed towards both FIG.


4


A and

FIG. 4B

wherein like numerals refer to like parts throughout.




As previously described, the pattern adapter


102


(corresponding to either the pattern adapter


102


of the high-density electrical connector


90


or the packaged integrated circuit connector


91


) is desirably placed within the recess


202


with an open area


225


surrounding the adapter


102


to allow for adjustments in its position and orientation. When inserted into the receptacle


200


, the pattern adapter


102


is engaged by each pushrod


220


which exert a bias on the adapter


102


. When the adapter


102


is in a resting position, the bias


223


exerted by each pushrod


220


against the adapter sides


114


is in a state of equilibrium.




In one aspect, during positioning and alignment of the adapter


102


, pushrods


220


are selectively retracted into or extended from the recess sidewalls


212


. Using selectively controlled pushrod movements, the bias on the adapter sides


114


is altered to reposition the adapter


102


within the receptacle


200


using lateral and rotational movements. In the illustrated embodiment, each pushrod


220


is independently controllable and extends to engage the adapter sides


114


, positioning the adapter


102


so as to insure the first contact pattern


124


of the adapter


102


remains properly aligned with the second contact pattern


206


of the receptacle


200


.





FIG. 5

further illustrates a cross-sectional view of the mechanism for aligning the pattern adapter


102


(corresponding to either the pattern adapter


102


of the high-density electrical connector


90


or the packaged integrated circuit connector


91


) using pushrod assemblies


210


. Each pushrod assembly


210


comprises a pushrod housing


230


that defines a cavity


231


which contains the pushrod


220


and further contains a shaped metal alloy (SMA) spring


240


. In the illustrated embodiment, the pushrod


220


is substantially cylindrical in shape and is desirably formed from a durable material such as plastic, metal, ceramic, or carbon fiber which is resistant to deformation. The spring


240


is desirably positioned behind the pushrod


220


and wholly contained within the pushrod housing


210


. In one aspect, the spring


240


comprises a shaped metal alloy (SMA) coiled wire spring designed to exert an electrically controllable bias on the rear portion of the pushrod


220


as will be discussed in greater detail hereinbelow.




In one aspect, spring leads


246


, comprising wires or conductive traces, are attached to the spring


240


and extend through the receptacle


200


where they are further connected to a control unit


249


. The shape metal alloy forming the spring


240


is responsive to current passed through the spring


240


. In one aspect, the control unit


249


selectively directs the flow of current


253


through the spring leads


246


to the spring


240


altering its physical state. When sufficient electrical current


253


is passed through the spring


240


, the internal resistance of the shaped metal alloy results in the heating of the spring


240


. The spring


240


is desirably heated in this manner to produce a controllable contraction


264


of the spring


240


as the alloy composition changes crystalline state from a low temperature martensite form to a high temperature austenite form as is known in the art of thermally responsive metal composition and manufacture. The temperature-dependent change in crystalline state of the spring


240


results in contraction of the spring


240


and reduces the bias exerted by the spring


240


along the bottom of the pushrod


220


. The reduced spring bias further reduces the bias


223


(

FIGS. 4A

,


4


B) exerted by the pushrod


220


on the adapter side


114


and results in a shift in position of the pattern adapter


102


as the bias of other pushrods


220


against other adapter sides


114


exceeds the bias of the contracted spring


240


and pushrod


220


. Thus, with each pushrod contraction, a new state of equilibrium between the pushrods


220


and the adapter sides


114


is attained and results in the controllable positioning of the pattern adapter


102


within the receptacle


200


.




In one aspect, the pattern adapter


102


is dimensioned to have sides of approximately 1 cm to 10 cm in length. Additionally the magnitude of the force or bias generated by the springs


240


which is exerted and the pushrod


220


and further exerted on the adapter side


114


is in the range of 10 Newtons and 140 Newtons.




In one aspect, coordination of the forces exerted by various pushrod combinations desirably directs the movement and orientation of the pattern adapter


102


with a fine level of precision.

FIGS. 6A

, B illustrate exemplary pushrod engagement combinations which result in different repositionings of the pattern adapter


102


. As shown in

FIG. 6A

, lateral movement


300


is achieved by directing current through springs


240


of two pushrod assemblies


210


present along one side


114


of the adapter


102


. The resulting retraction


304


of the pushrods


320


reduces the bias on the adapter side


114


and is accompanied by a concomitant repositioning of the adapter


102


resulting from the bias directed by pushrods


310


present along the opposing side of the adapter


102


, which extend


302


and reposition the adapter


102


in the lateral direction


300


as shown.




Rotational movements of the pattern adapter


102


are likewise achieved by engaging other pushrod


220


combinations. As shown in

FIG. 6B

, retraction


304


of pushrods


320


positioned along opposite sides


114


of the adapter


102


results in a counterclockwise repositioning of the adapter


102


. The rotational movement is achieved through the coordinated bias exerted by extension


302


of the selected pushrods


310


following the retraction


304


of other selected pushrods


320


.




While the previous examples demonstrate two possible methods by which the adapter position is altered, it will be appreciated by those of skill in the art that through the use of selective pushrod engagement, other positional variations can be achieved using other combinations of pushrod motion to achieve desirable results in moving the pattern adapter


102


along other vectors. In one aspect, the electrically directed retraction of selected pushrods may be replaced with an electrically directed extension of selected pushrods. In this embodiment, the spring material is selected to expand following current passage through the spring and may be alternatively used to exert controllable bias against the adapter sides to result in the repositioning of the adapter


102


as needed.




Using the aforementioned methods of electrically induced spring contraction/expansion, the plurality of pushrods


220


present along the adapter sides


114


are directed to exert positioning bias on the high-density electrical connector


90


which may be repositioned within the recess


202


of the receptacle


200


as necessary. Thus, proper contact between the second surface of the adapter


112


and the first surface


204


of the receptacle


200


is maintained in a finely controlled manner with superior precision over existing methods of alignment.





FIGS. 7A

, B further illustrate the method by which the pattern adapter


102


position is detected and altered to align the first contact pattern


124


of the pattern adapter


102


with the second contact pattern


206


of the receptacle


200


. In the illustrated embodiment, the second contact pattern


206


is shown with a plurality of alignment sensors or probes


208


located substantially adjacent to each corner of the second contact pattern


206


. Each sensor


208


comprises a region


226


wherein a conductively isolated lead pair


229


is positioned. In one aspect, the lead pair


229


is connected to the control unit


249


which further detects current flow through the lead pair


229


when conductively joined. The exposed portion of each lead pair


229


comprises an electrically-conductive material which is present on the surface of the second contact pattern


206


.




The sensing contacts


130


on the second surface


112


of the pattern adapter


102


comprise conductive surfaces formed to be of substantially the same size as the alignment sensors


208


. The sensing contacts


130


are further positioned about the alignment sensors


208


so as to conductively join the lead pair


229


of the alignment sensors


208


when the pattern adapter


102


is misaligned. In one aspect, conductive joining of the lead pair


229


issues a signal to the control unit


249


in a manner that will be discussed in greater detail in subsequent Figures and discussion.




As shown in

FIG. 7A

, an exemplary misaligned pattern adapter


245


is positioned over the second contact pattern


206


of the receptacle


200


. In the illustrated embodiment, the misaligned pattern adapter


245


results in the positioning of sensing contacts


130


over the region of the alignment sensor


208


and further conductively joins the lead pair


229


of two alignment sensors


231


. While in this position, a signal


234


is issued to the control unit


249


corresponding to each alignment sensor


208


which is triggered by conductive joining of the lead pair


229


by the sensing contact


130


. In one aspect, the control unit


249


responds to the triggering of an alignment sensor


208


by engaging selective pushrods


220


(

FIG. 5

) to reposition the adapter


102


in the alignment direction


255


indicated until the signal


234


received from the alignment sensor


208


has ceased.





FIG. 7B

illustrates a properly aligned first contact pattern


124


and second contact pattern


206


. In the illustrated embodiment, selective pushrod engagement results in the repositioning of the pattern adapter


102


wherein each sensing contact


130


rests in a position where the lead pair


229


of the alignment sensor


208


is not conductively joined by the sensing contact


130


. In this position, the pattern adapter


102


and its corresponding first contact pattern


124


are aligned with the second contact pattern


206


of the receptacle


200


. Furthermore, in the aligned position, the alignment sensors


208


remain untriggered. Thus, the current position of the pattern adapter


102


is maintained and the pattern adapter


102


can be subsequently secured using the aforementioned methods of mounting for securing the pattern adapter


102


to the first surface.





FIGS. 8A

, B, C illustrate one embodiment of the method by which the sensor information is processed by the control unit to position the adapter within the receptacle. As shown in

FIG. 8A

, the sensing contacts


130


are located in pairs substantially adjacent to each corner of the first contact pattern


124


. When the adapter


102


is placed within the receptacle


200


(FIG.


3


), the sensing contacts


130


of the positioning adapter


102


are positioned substantially over the regions where the alignment sensors


208


of the second contact pattern


206


are located (FIG.


3


). When the adapter


102


is properly positioned within the receptacle


200


the first contact pattern


124


on the adapter


102


and the second contact pattern


206


in the receptacle


200


are aligned such that both patterns


124


,


206


are joined, providing the desired connectivity and conductivity characteristics. While in this position, the sensing contacts


130


on the adapter


102


desirably do not conductively join with the alignment sensors


208


by remaining slightly offset so as to prevent current flow between the sensing contacts


130


and the alignment sensors


208


.




While the adapter position


102


within the receptacle


200


has not reached a desired contact pattern aligned position, sensing contacts


130


conductively join with the alignment sensors


208


resulting in the control unit


249


issuing pushrod responses in a manner that will be described in greater detail hereinbelow. The conductive joining of the sensing contacts


130


with the alignment sensors


208


results in the issuance of electronic signals to the control unit


249


which interprets the signals to determine the corrections to the position of the adapter


102


required to achieve the desired contact pattern alignment. The control unit


249


directs the activity of the pushrod assemblies based on a series of state table information which define pushrod retraction combinations used to reposition the adapter


102


.




In one aspect, the pushrod retraction combinations may result in repositioning of the adapter


102


in four lateral directions


400


(Top, Down, Right, Left) and two rotational directions


402


(Clockwise, Counterclockwise). The trigger state table


410


shown in

FIG. 8B

illustrates one embodiment showing the direction


400


,


402


of desired adapter movement and resulting conductive triggering of alignment sensors


208


by the sensing contacts


130


. In the trigger state table


410


, each position


400


,


402


(Top, Down, Right, Left, Clockwise, Counterclockwise) is defined by a set of eight trigger states


420


corresponding to the conductive triggering of the alignment sensors


208


necessary to achieve the desired positioning. The state of triggering of the alignment sensors


208


is designated by a “1” when the alignment sensor


208


is triggered by the sensing contact


130


, or as untriggered and designated by a “0” in the state table. For example, should the sensing contacts


130


corresponding to the first surface of the adapter


102


trigger the upper alignment sensors (


10


,


20


), the state table determines the response which will be issued by the control unit


249


to the pushrod assemblies


210


. Thus, various combinations of alignment sensor triggering are designated by the trigger state table


410


and correspond to desired directional re-positionings which must be made by the control unit


249


and pushrod assemblies


210


to properly align the first contact pattern


124


of the pattern adapter


102


with that of the second contact pattern


206


of the receptacle


200


.




It will be appreciated by those of skill in the art that other combinations of sensor triggering, defining additional state table entries, may be used to achieve the required re-positioning of the pattern adapter


102


. Furthermore, the placement of the sensing contacts


130


and alignment sensors


208


may be changed to accommodate other contact patterns


124


and may define still other state tables used by the control unit


249


for adapter re-positioning movements. Thus, each of the aforementioned possible combinations represent additional embodiments of the present invention.




As previously described, the pushrods


220


positioned along each side of the adapter


102


generate a variable bias which result in adapter movements


400


,


402


in the directions indicated (Top, Down, Right, Left, Clockwise, Counterclockwise). The position control state table


430


, shown in

FIG. 8C

, illustrates each positional movement


400


,


402


(Top, Down, Right, Left, Clockwise, Counterclockwise) and a corresponding set of eight motion states


403


which represent pushrod activations appropriate to achieve the desired positioning. Each set of motion states


403


is associated with a set of trigger states


420


corresponding to the desired movement necessary to align the first contact pattern


124


of the pattern adapter


102


and the second contact pattern


206


of the receptacle


200


. The control unit


248


issues appropriate electrical current selectively directed to the pushrod assemblies


210


whose activity is desirably altered to re-position the pattern adapter


102


. The activity of each pushrod


220


is shown as retracted (resulting from current flow


253


through the SMA spring


240


) and designated by a “1”, or as engaged (no current flow


253


through the SMA spring


240


) and designated by a “0”.




For example, to achieve a clockwise rotation


404


,


406


of the position adapter


102


, two combinations of pushrod activity may be used. A first combination for clockwise rotation


404


directs pushrod assemblies


210


corresponding to the locations at the upper left


10


(state


1


) and lower right


50


(state


5


) sides of the adapter


102


to be desirably retracted by electrical current flow


253


determined by the control unit


249


. During this time other pushrods assemblies


210


are not altered by electrical current flow


253


. The retraction of the pushrods


10


,


50


along the two sides


114


results in a shifting of the adapter


102


in a clockwise direction


404


as a new state of equilibrium is reached within the receptacle


200


. A second combination for clockwise rotation


406


is achievable in a similar manner using the control unit


249


which directs the selective retraction of the pushrod assemblies


210


corresponding to the locations at the upper right


30


(state


3


) and lower left


70


(state


7


) sides of the adapter


102


. The other combinations of selective pushrod retraction operate in a like manner, wherein the control unit


249


directs the retraction of pushrods


220


as determined by the state table to achieve the desired movement of the adapter


102


. It will be appreciated by those of skill in the art, that other combinations of control unit


249


directed pushrod activity exist which may perform desirable movements of the position adapter


102


and thus represent additional embodiments of the present invention. One example of another such movement comprises diagonal movement of the position adapter


102


within the receptacle


200


.




Additionally, as shown in

FIG. 9A

, the sensing contacts


130


and corresponding alignment sensors


208


may be located in alternative positions along the adapter


102


and have a corresponding state table which defines a set of states to determine the selective retraction of the pushrods


220


by the control unit


249


. In the illustrated embodiment, shown in

FIG. 9A

, the alignment sensors


208


are positioned in pairs substantially equidistantly from each side of the adapter


102


. The resulting sensor configuration alters the trigger state table


450


(shown in

FIG. 9B

) for directing selective pushrod retraction as shown. In one aspect, the trigger state table


450


may include states which are designated as “don't care” states


465


(designated by an “x”), where the triggering of an alignment sensor


208


in a particular trigger state set


460


does not affect the positional decoding and resulting control unit re-positioning of the pattern adapter


102


. The position control state table


470


(shown in

FIG. 9C

) is used by the control unit


249


to selectively retract pushrods


220


as previously described and desirably results in the repositioning of the pattern adapter


102


in lateral and rotational directions.




The high-density electrical connector assembly of the present invention thus addresses the need for an improved electrical connector and overcomes the limitations of prior art connectors in a number of ways. The pattern adapter size, shape, and construction provides a flexible method to join electrically conductive components which have a high-density of contacts and must be reliably and securely joined to other structures. The pattern adapter can additionally be scaled up or down to accommodate both large and small applications and is particularly useful in joining large collections of wire or cable which may be of different sizes. Thus, many individual contacts can be made by the use of one connector, saving time and effort compared to connecting each wire or cable individually.




Furthermore, the aforementioned high-density electrical connector assembly possesses a near zero insertion force quality when joining the contact patterns. This is important to help preserve each electrical contact's structural and conductive integrity and prevent breakage of connector during coupling and decoupling of the connector components.




In the case of high-density electrical connector applications, proper alignment and positioning of the connector can be cumbersome and difficult to achieve. The use of the shaped memory metal spring and pushrod assemblies improve the ease and precision with which the connector can be operated. Additionally, the alignment process occurs quickly and with minimal operator intervention to insure that the connector is aligned in a desired manner and continuous conductive contact is maintained.




Although the foregoing description has described the invention in context for use with an adapter present in a high density electrical connector, it will be appreciated by those of skill in the art that the other applications of the present invention exist which represent other embodiments of the present invention. In one aspect the repositioning assembly can be fashioned to be used in conjunction with, for example, an electronics module, a hybrid electronic component, an integrated circuit or other device requiring a fine level control over the positioning of the interface between adjoining surfaces.



Claims
  • 1. A high density electrical connector assembly comprising:a first connector member with a first and second side wherein the first connector member comprises a plurality of electrical conductors on the first side and defines a first contact pattern on the second side comprising a first plurality of electrical contacts that are connected to corresponding electrical conductors; a second connector member that defines a first surface adapted to receive the second side of the first connector wherein the second connector member has a second contact pattern comprising a second plurality of electrical contacts formed on the first surface that correspond to the first contact pattern on the second side of the first connector member, wherein the first contact pattern is substantially aligned with the second contact pattern when the first connector member is engaged with the second connector member; and an alignment mechanism that engages with the first connector member and the second connector member wherein the alignment mechanism has a sensor assembly that determines whether the first contact pattern and the second contact pattern are precisely aligned such that there is electrical interconnection between the first and second plurality of electrical contacts and the alignment mechanism includes positioning assemblies which move the first and second connector members with respect to each other to precisely align the first and second contact patterns.
  • 2. The assembly of claim 1, wherein the sensor assembly is formed on both the first and second connector members for sensing the alignment between the first and second contact patterns.
  • 3. The assembly of claim 2, wherein the sensor assembly includes at least one probe formed on the second connector member and a plurality of sensing contacts formed on the first connector member wherein the probe and the plurality of sensing contacts are positioned such that the at least one probe sends signals indicative of the relative position between the first and second connector members based upon whether the at least one probe is electrically contacting one or more of the plurality of sensing contacts.
  • 4. The assembly of claim 3, wherein the alignment mechanism further comprises an electrically activated spring that receives electrical current when the at least one probe engages with the sensing contacts in a manner that indicates that the first and second electrical connectors are not precisely aligned.
  • 5. The assembly of claim 4, wherein the at least one alignment mechanism comprises a shaped memory metal spring that retracts when it receives an electrical current.
  • 6. The electrical connector according to claim 5 wherein said shape-memory metal comprises a nickel-titanium alloy.
  • 7. The assembly of claim 4, wherein the at least one probe comprises a plurality of probes that are geometrically distributed about the first surface of the second connector member and the plurality of sensing contacts are geometrically distributed about the second surface of the first connector member and the at least one alignment mechanism comprises a plurality of alignment mechanisms spaced about the second connector member so as to be able to engage a surface of the first connector member to thereby move the first connector member with respect to the second connector member in both lateral and rotational directions.
  • 8. The assembly of claim 7, wherein the plurality of probes and the plurality of sensing contacts are geometrically distributed such that at least some of the plurality of probes engage with the plurality of contacts when the first connector member is substantially aligned with second connector member and thereby provide an electrical signal to the corresponding alignment mechanisms to thereby precisely align the first and second contact patterns.
  • 9. The assembly of claim 8, wherein the first connector member comprises a pattern adapter having a first geometric configuration and a first and a second side and the second connector member defines a mounting location having the first geometric configuration.
  • 10. The assembly of claim 9, wherein the mounting location further comprises a receptacle having a recess for receiving the pattern adapter.
  • 11. The assembly of claim 9, further comprising a control unit which receives the signals sent by the at least one probe and selectively sends electrical current to the alignment mechanism and further directs the activity of the positioning assemblies.
  • 12. The assembly of claim 11, wherein the control unit selectively engages the positioning assemblies when one or more of the plurality of probes are engaged with one or more of the plurality of sensing contacts.
  • 13. The assembly of claim 1, further comprising a mechanism for fixedly attaching the first and second electrical connectors in a fixed relationship wherein the first and second electrical connectors are precisely aligned.
  • 14. The assembly of claim 13, wherein the mechanism for fixedly attaching the first and second electrical connectors is selected from the group consisting of screws, bolts, rods, tabs, and latches.
  • 15. A high-density electrical cable connector comprising:a pattern adapter having a first side, a second side and side surfaces, the second side further comprising a first contact pattern formed from a first plurality of electrical contacts conductively joined to a plurality of wires extending from the first side, the second side further comprising a plurality of sensing contacts comprising conductive surfaces positioned about the second side; a mounting location having a first surface wherein a second contact pattern is formed from a second plurality of electrical contacts and corresponds to the first contact pattern such that when the second side of the pattern adapter and the first surface of the mounting location are aligned and joined, the first and second contact patterns are conductively joined; an alignment mechanism, comprising a sensor assembly which detects the alignment of the first and second contact patterns and issues signals based on the alignment, and further comprising at least one electronically actuated pushrod assembly that generates a bias against the pattern adapter to align the position of the first contact pattern with the second contact pattern; a control unit, that receives the signals generated by the sensor assembly and induces the alignment of the first and second contact patterns by actuating the plurality of pushrods to result in lateral and rotational movements of the pattern adapter.
  • 16. The high density electrical cable connector according to claim 15, wherein the mounting location further comprises a receptacle having a recess for receiving the pattern adapter.
  • 17. The high-density electrical cable connector according to claim 15, wherein the plurality of pushrod assemblies further comprise a plurality of shape memory metal springs which contract when electrical current passes through the springs.
  • 18. The high-density electrical cable connector of claim 17 wherein the shape memory metal comprises a nickel-titanium alloy.
  • 19. The high-density electrical cable connector according to claim 18, wherein each spring exerts a bias on the pattern adapter that corresponds to signals generated by the sensor assemblies.
  • 20. The high-density electrical cable connector according to claim 19 wherein the control unit sends electrical current through the springs causing the springs to retract thereby reducing the bias exerted by selected pushrods on the pattern adapter and furthermore resulting in re-alignment of the pattern adapter.
  • 21. The high-density electrical cable connector of claim 15, wherein the first contact pattern comprises a geometrically distributed plurality of sensing contacts and the sensor assembly comprises a corresponding, geometrically distributed plurality of sensors.
  • 22. The high-density electrical cable connector of claim 21, wherein the sensors generate signals based on conductive engagement with one of more of the plurality of sensing contacts.
  • 23. The high-density electrical cable connector of claim 15, wherein the control unit further comprises a trigger state table which defines the position of the pattern adapter based on the conductive joining of the sensing contacts with the sensors.
  • 24. The high-density electrical cable connector of claim 23, wherein the trigger state table is linked to a control state table to direct electrical current through the a least one pushrod assemblies.
  • 25. The high-density electrical cable connector of claim 15, further comprising a mechanism for fixedly attaching the pattern adapter and mounting location in a fixed relationship wherein the first and second contact patterns are precisely aligned.
  • 26. The assembly of claim 25, wherein the mechanism for fixedly attaching the pattern adapter and mounting location comprises is selected from the group consisting of screws, bolts, rods, tabs, and latches.
  • 27. A device for aligning packaged integrated circuits comprising:a packaged integrated circuit assembly having a first side, a second side and side surfaces, the second side further comprising a first contact pattern formed from a first plurality of electrical contacts conductively joined to electronic components of the packaged integrated circuit assembly, the second side further comprising a plurality of sensing contacts comprising conductive surfaces positioned about the second side; a mounting location having a first surface wherein a second contact pattern is formed from a second plurality of electrical contacts and corresponds to the first contact pattern; an alignment mechanism, comprising a sensor assembly which detects the alignment of the first and second contact patterns and issues signals based on the alignment, and further comprising a plurality of electronically actuated pushrod assemblies which generate a bias against the packaged integrated circuit assembly to align the packaged integrated circuit and join the contacts of the first plurality of electrical contacts with the second plurality of electrical contacts; a control unit that receives the signals generated by the sensor assemblies and aligns the first and second contact patterns by actuating the plurality of pushrods to result in lateral and rotational movements of the packaged integrated circuit assembly.
  • 28. The device for aligning packaged integrated circuits according to claim 27, wherein the mounting location further comprises a receptacle having a recess for receiving the a packaged integrated circuit assembly.
  • 29. The device for aligning packaged integrated circuits according to claim 28, wherein the plurality of pushrod assemblies further comprise a plurality of shape memory metal springs that are altered by passage of electrical current through the springs to change the bias exerted by the pushrods.
  • 30. The device for aligning packaged integrated circuits according to claim 29 wherein the shape-memory metal comprises a nickel-titanium alloy.
  • 31. The device for aligning packaged integrated circuits according to claim 27, wherein the first contact pattern comprises a geometrically distributed plurality of sensing contacts and the sensor assembly comprises a corresponding, geometrically distributed plurality of sensors.
  • 32. The device for aligning packaged integrated circuits according to claim 31, wherein the sensors generate signals based on conductive engagement with one of more of the plurality of sensing contacts.
  • 33. The device for aligning packaged integrated circuits according to claim 29, wherein each spring exerts a bias on the position adapter.
  • 34. The device for aligning packaged integrated circuits according to claim 33, wherein the control unit directs current through the plurality of springs.
  • 35. The device for aligning packaged integrated circuits according to claim 34, wherein the control unit selectively directs the retraction of selected springs thereby reducing the bias exerted on the packaged integrated circuit assembly.
  • 36. The device for aligning packaged integrated circuits according to claim 35, wherein the control unit further comprises a trigger state table which defines the position of the packaged integrated circuit assembly based on the conductive joining of the sensing contacts with the sensors.
  • 37. The device for aligning packaged integrated circuits according to claim 36, wherein the trigger state table is linked to a control state table to direct electrical current through the plurality of pushrod assemblies.
  • 38. The device for aligning packaged integrated circuits according to claim 27, further comprising a mechanism for fixedly attaching the packaged integrated circuit assembly and mounting location in a fixed relationship.
  • 39. The device for aligning packaged integrated circuits according to claim 38, wherein the mechanism for fixedly attaching the packaged integrated circuit assembly and mounting location is selected from the group consisting of screws, bolts, rods, tabs, and latches.
  • 40. A method of precisely aligning a first electrical connector member to a second electrical connector member such that a plurality of contacts on a first contact pattern of the first connector member is electrically connected to a corresponding plurality of contacts on a second contact pattern of the second connector member, the method comprising:positioning the first connector member in proximity to the second connector member, such that the first and second contact patterns are grossly aligned; electrically sensing whether the first and second connector members are precisely aligned such that first and second plurality of contacts are electrically connected to each other; and electrically inducing movement between the first and second connector members so as to precisely align the connector members in response to electrically sensing whether the first and second connector members are precisely aligned.
  • 41. The method of claim 40, further comprising securing the first and second connector members in the precisely aligned state.
  • 42. The method of claim 41, wherein positioning the first connector member in proximity to the second connector member comprises positioning the first connector member into a receptacle defined by the second connector member that is sized to within a manufacturing tolerance to correspond to the first connector member such that the first contact pattern and the second contact pattern are aligned to within the manufacturing tolerance of the first connector member and the receptacle.
  • 43. The method of claim 42, wherein electrically inducing movement between the first and second connector members comprises inducing a mechanical apparatus that is engaged with the first and second connector member to move the first connector member within the receptacle such that the first connector member is precisely aligned with the second connector member.
  • 44. The method of claim 43, wherein inducing a mechanical apparatus to move the first connector member within the receptacle comprises providing current to a shape memory alloy spring that causes a member to move thereby resulting in a bias being applied between the first and second connector members.
  • 45. The method of claim 44, wherein electrically sensing whether the first and second connector members are precisely aligned comprises determining the relative location between at least one probe formed on the second connector member to at least one sensing contact formed on the first connector member.
  • 46. The method of claim 45, wherein determining the relative location between the at least one probe and the at least one sensing contact comprises generating a electrical signal when the at least probe is conductively joined to the sensing contact.
  • 47. The method of claim 46, wherein the electrical signal is further detected by a control unit.
  • 48. The method of claim 47, wherein the control unit decodes the signal using a trigger state table to determine the first and second connector member alignment.
  • 49. The method of claim 48, wherein the control unit induces the mechanical apparatus following decoding of the first and second connector member alignment.
  • 50. The method of claim 49, wherein the control unit induces the mechanical apparatus by sending an electrical current to the mechanical apparatus.
  • 51. The method of claim 50, wherein the control unit further uses a control state table to determine when to send the electric current to the mechanical apparatus.
RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No. 60/227,855 filed Aug. 23, 2000, the disclosure of which is hereby incorporated by reference.

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Provisional Applications (1)
Number Date Country
60/227855 Aug 2000 US