Patent Publication Number: US-8109789-B2

Title: Connector assembly with strain relief

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application relates to and claims priority benefit to co-pending U.S. Provisional Application No. 61/201,606, filed Dec. 12, 2008, and entitled “Shielded Connector Assembly With Strain Relief” (the “&#39;606 Application”). The entire disclosure of the &#39;606 Application is incorporated by reference herein in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to shielded connector, and more particularly to a shielded connector having a strain relief for use in high voltage applications. 
     Increased fuel costs and increased efforts at reducing environmental pollution have lead the automotive industry towards electric and hybrid electric vehicles (HEV). One design aspect of these vehicles is the consideration or requirements for a relatively high operating voltage. Consequently, specific components of some such known vehicles are designed to accommodate high operating voltages. 
     In some current automotive industry applications, a high voltage shielded connector is used to provide a stable, sealed mechanical and electrical connection between a high voltage plug connector and a header connector mounted to a metallic module. The connector may need to provide robust shielding continuity from a braided cable shield of an incoming multicore cable that supplies high voltage current to the shield on the plug connector. For example, the connector may need to ensure an electrically conductive pathway that is continuous between an incoming cable and a shield within the connector in order to provide shielding from electromagnetic interference. 
     One problem with known connectors is that the stiffness of the cable may transmit a high degree of tensile, bending, and torsional strain into the electrical interconnection between the braided cable shield and the plug shield component. For example, the movement of the cable outside of the connector may impart significant strain at interfaces between the cable and one or more components of the connector. The strain may result in separation of the cable from the components at the interfaces and thereby jeopardize the mechanical and electrical performance of the connector. 
     BRIEF DESCRIPTION OF THE INVENTION 
     In one embodiment, a connector assembly is provided. The connector assembly includes an outer housing, an inner housing, a collet, and a retainer. The outer housing longitudinally extends between a front end and a rear end. The rear end has an opening for receiving a cable. The inner housing is located within the outer housing and includes a shield that is electrically coupled with the cable to restrict emission of electromagnetic interference. The collet is disposed around the cable at the rear end of the outer housing. The collet includes longitudinally extending fingers that are configured to engage the cable. The retainer is secured to the rear end of the outer housing and secures the collet between the outer housing and the retainer. The retainer and the collet redirect strain imparted on the cable away from an interface between the shield and the cable. 
     In another embodiment, another connector assembly is provided. The connector assembly includes an outer housing subassembly, a cable, a collet and a retainer. The outer housing subassembly extends between a front end and a rear end. The cable extends from the rear end of the outer housing subassembly. The collet is affixed to the cable at the rear end of the outer housing subassembly and has an opening through which the cable extends. The retainer surrounds the collet and is secured to the outer housing subassembly. The collet and the retainer reduce strain imparted on the cable. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a front perspective view of a connector assembly in accordance with one embodiment of the present disclosure. 
         FIG. 2  is a rear perspective view of the connector assembly shown in  FIG. 1 . 
         FIG. 3  is an exploded view of a partially assembled connector assembly shown in  FIG. 1 . 
         FIG. 4  is an exploded view of the connector assembly shown in  FIG. 1 . 
         FIG. 5  is a front perspective view of a collet for the connector assembly shown in  FIG. 1  in accordance with one embodiment of the present disclosure. 
         FIG. 6  is a rear perspective view of the collet shown in  FIG. 5 . 
         FIG. 7  is a rear perspective view of a retainer for the connector assembly shown in  FIG. 1  in accordance with one embodiment. 
         FIG. 8  is a front perspective view of the retainer shown in  FIG. 7 . 
         FIG. 9  is a perspective view of a first stage of an assembly sequence of the connector assembly shown in  FIG. 1  in accordance with one embodiment. 
         FIG. 10  is a cross-sectional view of the first stage of the assembly sequence for the connector assembly shown in  FIG. 9 . 
         FIG. 11  is a perspective view of a second stage of an assembly sequence of the connector assembly shown in  FIG. 1  in accordance with one embodiment. 
         FIG. 12  is a cross-sectional view of the second stage of the assembly sequence for the connector assembly shown in  FIG. 11 . 
         FIG. 13  is a perspective view of a third stage of an assembly sequence of the connector assembly shown in  FIG. 1  in accordance with one embodiment. 
         FIG. 14  is a cross-sectional view of the third stage of the assembly sequence for the connector assembly shown in  FIG. 13 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  is a front perspective view of a shielded connector assembly  1  in accordance with one embodiment of the present disclosure.  FIG. 2  is a rear perspective view of the connector assembly shown in  FIG. 1 .  FIG. 3  is an exploded perspective view of a partially assembled connector assembly  1  of  FIG. 1 . The connector assembly  1  may mate with a header connector such as the header connector subassembly disclosed in co-pending U.S. patent application Ser. No. 12/539,261, filed Aug. 11, 2009, and entitled “Connector Assembly With Two Stage Latch.” The entire disclosure of the &#39;261 Application is incorporated by reference herein. The connector assembly  1  and the header connector may mate with one another to transfer power therebetween. The connector assembly  1  may be a high voltage connector assembly. For example, the connector assembly  1  may be capable of transferring electric current with a header connector assembly at a voltage up to approximately 600 volts. The connector assembly  1  may transfer current at voltages of at least approximately 42 volts. Alternatively, the connector assembly  1  may be an assembly that transfers electric current at a lesser voltage. The connector assembly  1  may be a vehicular connector assembly. For example, the connector assembly  1  may be used to transfer electric current between two or more electronic devices or modules in an automobile. The header connector may be mounted to a module such as a metallic module (not shown) in an automotive high voltage application. 
     The connector assembly  1  includes an inner housing subassembly  2 , an outer housing subassembly  3 , a spacer  41  (shown in  FIG. 3 ), a cable seal  42  (shown in  FIG. 3 ), a collet  4  (shown in  FIG. 3 ), and a retainer  5 . The outer housing subassembly  3  longitudinally extends between a front end  100  and a rear end  102  (shown in  FIG. 3 ). The front end  100  mates with a mating connector, such as a header connector (not shown). The rear end  102  includes an opening  104  that extends through the outer housing subassembly  3 . 
     The spacer  41  is a body that is located in the interior of the outer housing subassembly  3 . The spacer  41  is located between shields  23 ,  24  (shown in  FIG. 4 ) of the inner housing subassembly  2  and the cable seal  42 . The spacer  41  extends between opposite sides  302 ,  304  with an opening  306  extending therethrough. The opening  306  is sized or dimensioned to receive a cable  21  so that the cable  21  of the inner housing subassembly  2  may pass through the spacer  41 . The spacer  41  may provide a positive forward stop in the outer housing subassembly  3  for the cable seal  42 . For example, the spacer  41  may engage the cable seal  42  when the cable seal  42  is loaded into the outer housing subassembly  3  to limit how far the cable seal  42  may be displaced into the outer housing subassembly  3 . 
     The cable seal  42  includes an elastomeric body  308  that is disposed between the spacer  41  and the collet  4 . The cable seal  42  may provide a seal against the ingress of moisture and other contaminants into the interior of the outer housing subassembly  3  through the rear end  102  of the outer housing subassembly  3 . The body  308  extends between opposite sides  310 ,  312  with a cable opening  314  extending therethrough. The cable  21  of the inner housing subassembly  2  may pass through the cable seal  42  through the cable opening  314 . One or more post openings  316  may extend through the body  308 . In the illustrated embodiment, the post openings  316  are spaced around the periphery of the cable opening  314 , although a different number and/or arrangement of the post openings  316  may be provided than what is shown in  FIG. 3 . 
       FIG. 4  is an exploded view of the connector assembly  1  of  FIG. 1 . The inner housing subassembly  2  includes an inner housing  22 , the upper shield  23 , the lower shield  24 , the cable  21 , an inner ferrule  25 , and an outer ferrule  26 . The inner housing  22  is located between the shields  23 ,  24 . The inner housing  22  may include, or be formed from, a dielectric material. For example, the inner housing  22  may be molded from one or more polymers. The shields  23 ,  24  may be electromagnetic shields that shield one or more components of the connector assembly  1  from electromagnetic interference. For example, the shields  23 ,  24  may restrict emission of electromagnetic interference outside of the shields  23 ,  24 . The shields  23 ,  24  include one or more contact springs  231  that outwardly extend from the shields  23 ,  24 . For example, the springs  231  may be cantilevered beams that are biased toward the shields  23 ,  24  when the connector assembly  1  is loaded into a header connector assembly. In one embodiment, the springs  231  engage the header connector assembly to electrically couple the shields  23 ,  24  with the header connector assembly, such as with a shield of the header connector assembly. The shields  23 ,  24  combine to form an electromagnetic shield that substantially encloses the inner housing  22 . Alternatively, the shields  23 ,  24  may be provided as a single, unitary body formed from a conductive material, such as a metal or metal alloy. The inner housing  22  also includes slots  222  to provide temporary retention of the upper shield  23  and lower shield  24  prior to the installation of the inner housing subassembly  2  into the outer housing subassembly  3 . For example, the shields  23 ,  24  may include inwardly protruding ridges  404 ,  406  that are received in the slots  222  to secure the shields  23 ,  24  to the inner housing  22 . 
     The shields  23 ,  24  have rear openings  400 ,  402  (shown in  FIG. 4 ) that form an opening  300  (shown in  FIG. 3 ) when the shields  23 ,  24  are coupled to the inner housing  22 . The cable  21  is inserted through the opening  300  defined by the rear openings  400 ,  402 . The cable  21  includes one or more inner cores  200  (shown in  FIG. 2 ) that longitudinally extend through the cable  21 . The cores  200  may be wires capable of transmitting electric power. In the illustrated embodiment, the cable  21  is a multicore cable with a braided cable shield  27  (shown in  FIG. 2 ). Each of the inner cores  200  is terminated with a terminal  28  crimped around the end of the corresponding inner core  200 . The inner housing  22  comprises cavities  29  (shown in  FIG. 1 ) for accommodating the terminals  28 . The cavities  29  may receive contacts or terminals (not shown) of the header connector (not shown) with which the connector assembly  1  mates to electrically couple the header connector and the connector assembly  1 . 
     As further shown in  FIG. 4 , the outer housing subassembly  3  comprises an outer housing  31 , a peripheral seal  32 , and a peripheral seal retainer  33 . The outer housing  31  comprises a generally cylindrical body for accepting the inner housing subassembly  2 . The outer housing  31  includes one or more outwardly protruding lugs  311  located on the outer surface of the outer housing  31 . The peripheral seal  32  extends around the outer perimeter of the opening in the outer housing  31  at the front end  100 . The peripheral seal  32  may be an elastomeric body that is compressed between the front end  100  of the outer housing  31  and the peripheral seal retainer  33 . The peripheral seal retainer  33  may be joined to the outer housing  31  to secure the peripheral seal  32  in the front end  100  of the outer housing  31 . The peripheral seal  32  may prevent ingress of moisture and other contaminants into the interior of the outer housing  31 . 
     The inner and outer ferrules  25 ,  26  may include, or be formed from, a conductive material, such as a metal or metal alloy. The inner ferrule  25  may be placed over the cable  21  such that the cable  21  extends through the inner ferrule  25 . The inner ferrule  25  may be placed over an exposed portion  408  of the braided cable shield  27 . The outer ferrule  26  is placed over the inner ferrule  25  and may be crimped onto the shields  23 ,  24  at or proximate to the rear openings  400 ,  402 . The inner ferrule  25  and outer ferrule  26  may mechanically couple and secure the shields  23 ,  24  with the cable shield  27 . Alternatively, the outer and/or inner ferrules  26 ,  25  may provide an electrically conductive path between the shields  23 ,  24  and the cable shield  27 . For example, the inner ferrule  25  may be electrically coupled to the cable shield  27  with the outer ferrule  26  being electrically coupled with the shields  23 ,  24 . The cable shield  27  may be electrically joined with an electric ground reference to electrically couple the shields  23 ,  24  with the electric ground reference via the ferrules  25 ,  25 . The shields  23 ,  24  may shield the inner housing  22  from electromagnetic interference via this electric coupling with the electric ground reference. As described herein, movement of the cable  21  may impart stress in connections between the cable shield  27  and one or more of the shields  23 ,  24  and/or may separate the shields  23 ,  24  from one another. The collet  4  may be secured to the cable  21  outside of the coupling of the cable shield  27  with the shields  23 ,  24  to prevent such stresses from separating the cable shield  27  from the shields  23 ,  24  and/or to prevent the shields  23 ,  24  from moving, separating, or breaking apart from one another. 
       FIG. 5  is a front perspective view of the collet  4  and  FIG. 6  is a rear perspective view of the collet  4  in accordance with one embodiment of the present disclosure. The collet  4  includes a planar body  43  having a central opening  431  extending therethrough. The body  43  is planar in that the thickness of the body  43  is significantly smaller than the dimensions of the body  43  in at least two other directions that are perpendicular to the thickness of the body  43 . The thickness of the body  43  extends between a front side  432  and a rear side  433 . When assembled to the outer housing subassembly  3  (shown in  FIG. 1 ), the front side  432  of the collet  4  faces the interior of the outer housing  31  (shown in  FIG. 4 ) while the rear side  433  faces away from the interior of the outer housing  31 . 
     The body  43  is sized and shaped to coordinate with the spacer  41  (shown in  FIG. 3 ), the cable seal  42  (shown in  FIG. 3 ), and the retainer  5  (shown in  FIG. 2 ). For example, the body  43  may enclose the spacer  41  and the cable seal  42  within the outer housing  31  (shown in  FIG. 3 ) while fitting between the retainer  5  and the outer housing  31 . One or more posts  434  extend from the front side  432 . The posts  434  forwardly protrude from the front side  432  toward the interior of the outer housing  31  when the collet  4  is assembled to the outer housing  31 . The posts  434  may be sized, shaped and located to fit in corresponding ones of the post openings  316  (shown in  FIG. 3 ) of the cable seal  42  (shown in  FIG. 3 ). The posts  434  may be received in the post openings  316  to orient and align the collet  4  with respect to the cable seal  42 . Additionally, the posts  434  may be received into the post openings  316  to ensure that the collet  4  is positioned relative to the cable seal  42  such that the cable seal  42  is approximately evenly compressed by the collet  4  when the connector assembly  1  is assembled. Alternatively, different components may be used to orient and/or align the collet  4  with respect to the cable seal  42 . For example, a different type of projection such as a protrusion, nub, or other extension may be used in place of or in addition to the posts  434 . 
     One or more fingers  435  rearwardly extend from the rear side  433 . The fingers  435  are located around the periphery of the opening  431 . In the illustrated embodiment, the fingers  435  are flexible cantilevered beams that extend from the body  43  to corresponding outer ends  500 . The fingers  435  may flex inward toward one another and outward away from one another. For example, the fingers  435  may outwardly flex away from one another to fit over the exterior or outer jacket of the cable  21  (shown in  FIG. 3 ) when the when the collet  4  is installed over the cable  21 . 
     The fingers  435  include inner surfaces  436  (shown in  FIG. 5 ) and opposite outer surfaces  437  (shown in  FIG. 6 ). In the illustrated embodiment, the inner surfaces  436  are serrated. For example, the inner surfaces  436  may include serrated or stair-step edges  438  extending across the fingers  435  in a transverse direction with respect to the elongation direction of the fingers  435 . The edges  438  engage the cable  21  to retain the collet  4  on the cable  21 . For example, the edges  438  may provide teeth that bite into and engage the outer jacket or surface of the cable  21  to secure the collet  4  to the cable  21  when the fingers  435  are compressed onto the cable  21 . Also as shown in the illustrated embodiment, the fingers  435  include raised ribs  440  extending longitudinally along the outer surfaces  437 . The ribs  440  define recessed slots  502  longitudinally extending along the outer surfaces  437  of the fingers  435 . The fingers  435  are separated from one another by air gaps  504  between the outer edges of the fingers  435 . The fingers  435  include inside ramped surfaces  439  and outside ramped surfaces  441  disposed at the outer, or free, ends  500  of the fingers  435 . The inside ramped surfaces  439  facilitate assembly of the collet  4  onto the cable  21  (shown in  FIG. 2 ). The outside ramped surfaces  441  cooperate with an inner surface  800  (shown in  FIG. 8 ) of an angled surface  525  (shown in  FIG. 7 ) on the retainer  5  (shown in  FIG. 1 ) to compress the fingers  435  onto the cable  21 . 
       FIGS. 7 and 8  are perspective views of the retainer  5  in accordance with one embodiment of the present disclosure. The retainer  5  longitudinally extends between a front end  700  and a rear end  702  with an opening  704  extending therethrough. The retainer  5  includes a compression section  52  (shown in  FIG. 7 ) and a shroud section  53 . The compression section  52  intersects the shroud section  53  between the front and rear ends  700 ,  702 . In the illustrated embodiment, the compression section  52  extends from the rear end  702  to the shroud section  53  and the shroud section  53  extends from the front end  700  to the compression section  52 . 
     The compression section  52  includes an inner surface  521  and an opposite outer surface  522  (shown in  FIG. 7 ). One or more stiffening ribs  523  that longitudinally extend along the outer surface  522 . The ribs  523  add material to the compression section  52  to provide additional strength or stiffness of the compression section  52  against bending or side-to-side flexing. One or more stabilizing ribs  524  longitudinally extend along the inner surface  521  of the compression section  52 . The stabilizing ribs  524  engage the fingers  435  (shown in  FIG. 5 ) of the collet  4  (shown in  FIG. 3 ) to stabilize the collet  4 . For example, the stabilizing ribs  524  may engage the slots  502  (shown in  FIG. 5 ) and/or be disposed in the air gaps  504  (shown in  FIG. 5 ) to engage the sides of the fingers  435 . The engagement between the stabilizing ribs  524  and the fingers  435  may prevent rotation or rotational movement or flexing of the fingers  435  when torsional stress is applied to the cable  21 , such as by rotating or twisting the cable  21  (shown in  FIG. 2 ) relative to the collet  4 . 
     The compression section  52  includes a slanted section  525  that has an outer surface  522  and the inner surface  800 . The slanted section  525  includes the inner surface  800  that cooperates with the outside ramped surfaces  441  (shown in  FIG. 5 ) of the fingers  435  (shown in  FIG. 5 ) of the collet  4  (shown in  FIG. 3 ) to compress the fingers  435  onto the cable  21  (shown in  FIG. 2 ). For example, the retainer  5  may be positioned over the collet  4  such that the fingers  435  slide from the front to the back along the inner surface  800  and are inwardly biased by the inner surface  800  such that the fingers  435  are compressed onto the cable  21 . 
     The shroud section  53  of the retainer  5  fits over the rear end  102  (shown in  FIG. 3 ) of the outer housing assembly  3  (shown in  FIG. 1 ). In the illustrated embodiment, the shroud section  53  includes openings  706  extending through the shroud section  53 . The openings  706  may receive the lugs  311  (shown in  FIG. 4 ) of the outer housing assembly  3  to secure the retainer  5  to the outer housing  31  (shown in  FIG. 4 ) of the outer housing assembly  3 . Once secured to the outer housing  31 , the retainer  5  encloses the rear end  102  (shown in  FIG. 3 ) of the outer housing  31  to enclose the collet  4  (shown in  FIG. 3 ), the cable seal  42  (shown in  FIG. 3 ), and the spacer  41  (shown in  FIG. 3 ) therein. 
       FIGS. 9 through 14  illustrate steps of assembling the collet  4  and the retainer  5  to the connector assembly  1  in accordance with one embodiment of the present disclosure.  FIG. 9  is a perspective view of the connector assembly  1  in a first stage of assembling the collet  4  and retainer  5  to the connector assembly  1 .  FIG. 10  is a cross-sectional view of the connector assembly  1  shown in  FIG. 9 . The inner subassembly  2  is placed within the outer subassembly  3 . In the first stage, the cable  21  is slid through the opening  314  of the cable seal  42  from the front side  310  of the cable seal  42  and the central opening  431  of the collet  4  from the front side  432  of the collet  4 . 
       FIG. 11  is a perspective view of the connector assembly  1  in a second stage of assembling the collet  4  and retainer  5  to the connector assembly  1 .  FIG. 12  is a cross-sectional view of the connector assembly  1  shown in  FIG. 11 . In the second stage, the collet  4  is moved or slid toward the outer housing subassembly  3  until the posts  434  (shown in  FIG. 5 ) of the collet  4  are received into the corresponding openings  316  (shown in  FIG. 3 ) in the cable seal  42 . The body  43  of the collet  4  mates with the rear end  102  of the outer housing subassembly  3 . As shown in  FIG. 12 , the collet  4  mates with the rear end  102  to enclose the cable seal  42 , the spacer  41 , the shields  23 ,  24  (shown in  FIG. 4 ), and the inner housing  22  (shown in  FIG. 4 ) in the outer housing subassembly  3 . Although not shown in  FIG. 12 , the fingers  435  of the collet  4  may be outwardly biased away from one another and the cable  21  in the second stage of assembly. 
       FIG. 13  is a perspective view of the connector assembly  1  in a third stage of assembling the collet  4  and retainer  5  to the connector assembly  1 .  FIG. 14  is a cross-sectional view of the connector assembly  1  shown in  FIG. 13 . The third stage of assembling the connector assembly  1  may be the final stage of assembly. In the third stage, the retainer  5  is slid over the cable  21  and the collet  4 . As the retainer  5  slides over the collet  4 , the stabilizing ribs  524  (shown in  FIG. 7 ) of the retainer  5  may be positioned between the ribs  440  (shown in  FIG. 5 ) on the fingers  435  of the collet  4 , or within the slots  502  (shown in  FIG. 5 ) defined by the ribs  440 . Alternatively, the stabilizing ribs  524  may be disposed between the fingers  435  within the air gaps  504  (shown in  FIG. 5 ). The inner surface  800  of the retainer  5  moves relative to and over the fingers  435  of the collet  4  to pass the collet  4  onto the cable  21 . The slanted surface  525  inwardly biases the fingers  435  toward one another such that the fingers  435  are compressed onto the cable  21 . The fingers  435  may be compressed onto the cable  21  such that the serrated edges  438  (shown in  FIG. 6 ) of the fingers  435  engage the cable  21  to secure the collet  4  to the cable  21 . 
     The openings  706  in the retainer  5  accept the lugs  311  of the outer housing subassembly  3  to secure the retainer  5  to the rear end  102  of the outer housing subassembly  3 . The retainer  5  encloses the collet  4 , the cable seal  42 , the spacer  41 , and the inner housing subassembly  2  within the outer housing subassembly  3  while permitting the cable  21  to rearwardly extend and protrude through the retainer  5 . 
     In one embodiment, once the retainer  5  is secured to the outer housing subassembly  3 , movement of the cable  21  outside of and relative to the connector assembly  1  may result in strain being imparted on interfaces between the cable  21  and one or more other components of the connector assembly  1 . For example, movement of the cable  21  outside of the connector assembly  1  may impart a strain at interfaces between the cable  21  and components to which the cable  21  is joined. Instead of the strain being applied to the interface between the cable  21  and the shields  23 ,  24  (shown in  FIG. 4 ) of the inner housing subassembly  2 , the collet  4  and/or retainer  5  may restrict movement of the cable  21  outside of and away from the interface between the cable  21  and the shields  23 ,  24  to redirect the strain away from the interface. For example, the portion of the cable  21  that is outside of the connector assembly  1  is permitted to be moved relative to the connector assembly  1  while the portion of the cable  21  that is located within the connector assembly  1  between the compression section  52  of the retainer  5  and the shields  23 ,  24  is restricted from movement relative to the connector assembly  1 . As a result, the strain imparted at interfaces between the cable  21  and other components of the connector assembly  1  is isolated away from the inner housing subassembly  2  and the shields  23 ,  24  and may be redirected to the relatively stiff collet  4  and/or the retainer  5 , where the strain may not cause separation of the cable  21  from the connector assembly  1 . 
     Dimensions, types of materials, orientations of the various components, and the number and positions of the various components described herein are intended to define parameters of certain embodiments, and are by no means limiting and are merely exemplary embodiments. Many other embodiments and modifications within the spirit and scope of the claims will be apparent to those of skill in the art upon reviewing the above description. The scope of the invention should, therefore, be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. In the appended claims, the terms “including” and “in which” are used as the plain-English equivalents of the respective terms “comprising” and “wherein.” Moreover, in the following claims, the terms “first,” “second,” and “third,” etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. Further, the limitations of the following claims are not written in means-plus-function format and are not intended to be interpreted based on 35 U.S.C. §1102, sixth paragraph, unless and until such claim limitations expressly use the phrase “means for” followed by a statement of function void of further structure.