Abstract:
A cable connector backshell assembly for high frequency applications requiring reduced electromagnetic emissions. Aspects include providing sufficient physical spacing and electrical isolation between the signal conductors and the housing to meet EMI standards for HIPPI-6400 connector assemblies. One embodiment includes spring preloading of the electrical connecter. One embodiment includes a longitudinally floating connector.

Description:
RELATED APPLICATIONS  
       [0001]    This application is a Divisional Application of U.S. patent application Ser. No. 09/730,077, filed Dec. 5, 2000, entitled BACKSHELL ASSEMBLY, which claims priority to U.S. Provisional Patent Application No. 60/215,472, filed Jun. 30, 2000. 
     
    
     
       TECHNICAL FIELD OF THE INVENTION  
         [0002]    The present invention relates generally to the field of electrical connectors, and, in particular, to a connector backshell assembly suitable for applications prone to high levels of radiated electromagnetic emissions.  
         BACKGROUND  
         [0003]    Electromagnetic interference (EMI) affects the performance of electrical circuits. Reduction of sensitivity to EMI, as well as the reduction of radiated levels of EMI, is an important consideration in the design of electrical circuits and devices. With increasing power levels and frequency, spurious radiation emissions also rises. Conversely, circuits operating with reduced power levels are particularly sensitive to undesirable radiation.  
           [0004]    Designers often rely on gaskets and other shielding measures to reduce EMI transmissions. An area of particular interest concerns adequate shielding for high density connectors. Density refers to the number of electrical connections in a given area of a connector. A typical high density connector has 100 pins in the space having dimensions of approximately 38 mm by 10 mm, or an area of 3.8 cm 2 . An example of an application calling for such a connector is the High Performance Parallel Interface-6400 (HIPPI-6400) protocol. HIPPI-6400 relates to high frequency, digital data transmissions at 6400 Mbit/s of data per direction. Common mode currents on outer shields due to capacitive coupling and poor bonding of shielding components can result in the failure to meet applicable EMI compliance standards.  
           [0005]    High density connectors are also prone to undesirable capacitive coupling between the connector housing and individual pins within the connector. As capacitive coupling rises, so to do levels of EMI radiation.  
           [0006]    One proposed solution to ameliorate EMI radiation involves gasketing between the connector nose and connector housing while reducing capacitive coupling with increased spacing. Proper assembly technique requires that the connector pins and receivers are filly mated at a time when the gasket material, positioned between the nose of the connector backshell and the housing for the electronic circuitry, is sufficiently compressed. In this state, the proper electrical connection is established at the connector halves and the gasket has sufficiently low impedance with the housing such that an effective EMI seal is established. However, manufacturing tolerances often frustrate achievement of this result. In some cases, the connector pins will have reached the bottom of the connector receiver before the gasket material is sufficiently compressed, resulting in a higher impedance coupling to the housing and undesirable EMI leakage. If the connector jackscrews are tightened beyond a point where the connector assembly is fully mated, then it is likely that the connector, standoffs, or connector jackscrews will be damaged.  
           [0007]    For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a connector assembly to address the problem of undesirable EMI transmissions without adversely effecting the electrical connection.  
         SUMMARY  
         [0008]    The above mentioned problems associated with connector assemblies for applications prone to interference from high levels of radiated electromagnetic emissions, and other problems, are addressed by the present invention and will be understood by reading and studying the following specification.  
           [0009]    In particular, an illustrative embodiment of the present invention includes a connector apparatus comprising an electrical connector, an insulative member encasing the electrical connector, an electrically conductive housing, and a plurality of clamping screws. The electrical connector has a cable end and a coupling end wherein the cable end is adapted for receiving a conductive cable and the coupling end is adapted for mating with a matching connector. The insulative member surrounds the electrical connector between the cable end and the coupling end. The housing is adapted to receive the insulative member and includes a nose end and a cable orifice wherein the nose end is proximate to the coupling end and the cable orifice is proximate to the cable end. The housing includes a bottom and a lid. The clamping screws engage the housing and are threadably coupled with the matching connector.  
           [0010]    In one embodiment, the insulative member displaces the conductive cable relative to the housing. In one embodiment, the insulative member is rigidly captivated by the electrically conductive housing. In one embodiment, the electrically conductive housing includes a way aligned substantially on an axis defined by the nose end and the cable orifice wherein the insulative member couples with the way. In one embodiment, the connector apparatus comprises a spring coupled to the housing and adapted to urge movement of the connector in a direction along the axis. In one embodiment, the insulative member is plastic.  
           [0011]    In one embodiment, the present subject matter provides a backshell comprising an electrical connecter, a housing, a clamping screw and a spring. The electrical connecter includes sides, a mating end and a cable end and the connector includes an insulated shell substantially surrounding the sides. The mating end is adapted to mate with a matching connector in an electrical circuit housing and the cable end adapted to receive an electrical conductor of a cable. The housing has a longitudinal axis and includes a mating face near a first end of the axis, a cable orifice near a second end of the axis, two side walls aligned substantially parallel to the longitudinal axis, a bottom and a lid defining an interior of the housing. The mating end is proximate the mating face and the cable end is proximate the cable orifice. The housing includes a way for receiving the electrical connector and is adapted for permitting relative movement of the electrical connector and the housing along the longitudinal axis. The housing includes a clamping surface having a fixed position relative to the mating face. The housing includes a bore aligned substantially parallel with the longitudinal axis. The housing is electrically conductive. The clamping screw has a thread portion, a shoulder and a head. The clamping screw passes through the bore and the thread portion is proximate the mating face and the head is proximate the cable orifice. The shoulder is adapted for exerting pressure on the clamping surface. The spring exerts a force urging the electrical connector in the direction of the mating face. Engagement of the clamping screw with a threaded standoff associated with the matching connector causes the mating face to be drawn towards the electrical circuit housing and the spring urges the electrical connector to engage the matching connector.  
           [0012]    In one embodiment, the spring is threaded on the clamping screw. In one embodiment, the spring is a tension spring. In one embodiment, the spring exerts a force on the clamping surface.  
           [0013]    In one embodiment, the housing includes a clamping surface having a fixed position relative to the mating face and the housing includes a bore aligned substantially parallel with the longitudinal axis. The housing is electrically conductive. Furthermore, the embodiment includes a clamping screw having a thread portion, a shoulder and a head with the clamping screw passing through the bore and the thread portion is proximate the mating end and the head is proximate the cable orifice. The shoulder is adapted for exerting pressure on the clamping surface. Furthermore, the embodiment includes a spring threaded on the clamping screw and exerting opposing forces on the clamping surface and the electrical connector. Engagement of the clamping screw with a threaded standoff associated with the matching connector causes the mating face to be drawn towards the electrical circuit housing and the spring urges the electrical connector to engage the matching connector.  
           [0014]    In one embodiment, the way permits travel of the connector beyond the mating face. In one embodiment, the housing comprises a metal housing. In one embodiment, the electrical connector sides are metal.  
           [0015]    In an alternative embodiment, the subject matter provides a connector apparatus comprising an electrical connecter, a metal housing and a clamping screw. The electrical connecter has sides, a mating end and a cable end and an insulated shell substantially surrounding the sides. The mating end is adapted to mate with a matching connector coupled to an electrical circuit housing and the cable end is adapted to receive an electrical conductor of a cable. The metal housing has a longitudinal axis and includes a mating face near a first end of the axis, a cable orifice near a second end of the axis, two side walls aligned substantially parallel to the longitudinal axis, a bottom and a removable lid defining an interior of the housing. The mating end is proximate the mating face and the cable end is proximate the cable orifice. The housing is adapted for receiving the electrical connector and includes a clamping surface. The clamping surface is proximate to one of the side walls and extending towards the interior space. The clamping surface has a bore aligned substantially parallel with the longitudinal axis. The clamping screw has a thread portion, a shoulder and a head. The clamping screw passes through the bore in the clamping surface and the thread portion is proximate the mating end and the head is proximate the cable orifice. The shoulder is adapted for exerting clamping pressure on the clamping surface. Engagement of the clamping screw with a threaded standoff associated with the matching connector causes the mating face to be drawn towards the electrical circuit housing.  
           [0016]    In one embodiment, the removable lid is electrically conductive. In one embodiment, the removable lid includes a plurality of clearance holes and the metal housing includes a plurality of threaded holes aligned with the plurality of clearance holes and the removable lid is secured to the housing using threaded fasteners. In one embodiment, the mating face of the metal housing exerts pressure on the electrical circuit housing. In one embodiment, the insulated shell comprises a plastic housing adapted to receive the electrical connector.  
           [0017]    In an alternative embodiment, the present subject matter provides a connector housing comprising a conductive receptacle, a clamping surface and a connector cavity. The conductive receptacle has an interior and an exterior, as well as a nose end and a terminating end aligned substantially along a longitudinal axis. The clamping surface is coupled to the receptacle and the clamping surface is adapted to oppose a force exerted on an axis aligned substantially parallel to the longitudinal axis. The connector cavity is on the interior of the receptacle and receives an electrical connector encased in an insulative jacket. The electrical connector is adapted for coupling to a cable and the cable is routed via the terminating end. The conductive receptacle is electrically isolated from the connector and the conductors of the cable.  
           [0018]    In one embodiment, the receptacle includes a conductive metal. In one embodiment, the clamping surface is located within the interior of the receptacle.  
           [0019]    In an alternative embodiment, the present subject matter provides a method of manufacturing a connector, with the method comprising providing a conductive housing, providing an electrical connector, providing an insulative jacket and providing a mechanical fastener. The conductive housing has a nose and a terminating end and includes an interior and an exterior. The electrical connector includes a plurality of conductive members and is encased in a conductive jacket. The insulative jacket surround s the conductive jacket of the electrical connector and the insulative jacket is rigidly secured to the electrical connector. The mechanical fastener enables coupling the housing to a matching connector.  
           [0020]    In one embodiment, the method comprises assembling a cable to the electrical connector. In one embodiment, the method comprises coupling the connector with the housing. In one embodiment, the method comprises assembling a lid to the conductive housing. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]    [0021]FIG. 1A illustrates an isometric view of one embodiment of the present system.  
         [0022]    [0022]FIG. 1B illustrates a view of the present system when assembled to a matching connector.  
         [0023]    [0023]FIG. 2 illustrates an isometric view of a portion of one embodiment of the present system.  
         [0024]    [0024]FIG. 3 illustrates a side view of the portion shown in FIG. 2.  
         [0025]    [0025]FIG. 4 illustrates a top view of an embodiment of the present system.  
         [0026]    [0026]FIG. 5 illustrates a top view of an embodiment of the present system.  
         [0027]    [0027]FIGS. 6A and 6B illustrate a top view and an end view, respectively, of an embodiment of the present system.  
         [0028]    [0028]FIG. 6C illustrates a side view of a portion of one embodiment of the present system.  
         [0029]    [0029]FIGS. 7A, 7B,  7 C and  7 D illustrate portions of one embodiment of the present system.  
         [0030]    [0030]FIGS. 8A, 8B,  8 C and  8 D illustrate different views of a connector shell suitable for use with the present system.  
         [0031]    [0031]FIGS. 9A and 9B illustrate various electromagnetic interference bonding mechanisms for cable shielding. 
     
    
     DETAILED DESCRIPTION  
       [0032]    The following detailed description refers to the accompanying drawings which form a part of the specification. The drawings show, and the detailed description describes, by way of illustration specific illustrative embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. Other embodiments may be used and mechanical and electrical changes may be made without departing from the scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense. Like reference numbers refer to similar items in all the figures.  
         [0033]    In the following detailed description, the present system relates to the backshell assembly. The backshell assembly includes the connector, the cable end, and the housing in which the connector is encased. The connector of the backshell assembly mates with a matching connector affixed to an electronic circuit housing or circuit board. As used herein, references to the forward direction are understood to mean in a direction towards the matching connector. Consequently, to engage the electrical connector, the backshell assembly is moved in the forward direction. The rearward direction is understood to denote in a direction away from the matching connector. Consequently, to disengage the electrical connector, the backshell assembly is moved in the rearward direction.  
         [0034]    In embodiments shown herein, the connector is marketed under the trademark MICROPAX®. MICROPAX® is a registered trademark of Berg Technology, Inc., One East First Street, Reno, Nev. 89501. The MICROPAX® connector includes a conductive shell and paddleboards for making connection to a cable as well as a matching connecter. One embodiment of the MICROPAX® connector meets the standards of HIPPI-6400. Other connectors, shells or components may also be utilized in the present system. The present system is suited for applications wherein EMI is possible. One typical application entails a high frequency connector having high density. It is understood, however, that the present system is not so limited, and may be used, for example, with low density connectors and in applications where EMI radiation is not a significant concern.  
         [0035]    [0035]FIG. 1A depicts one embodiment of the present subject matter, backshell assembly  100 , with the lid removed. Backshell assembly  100  includes housing  110 . In one embodiment, housing  110  is fabricated of electrically conductive material, such as aluminum. Alternatively, housing  110  may be fabricated of insulative material having a conductive layer, in which case, the conductive layer may be internal, external or elsewhere relative to housing  110 . Housing  110  has mating face  115  adapted for mating with a conductive circuit housing, or a conductive circuit housing with a conductive gasket. Housing  110  also has a back wall, the interior surface of which is designated as item  150  in FIG. 1, and the exterior surface of which is designated as item  175  in FIG. 1.  
         [0036]    In the embodiment shown, assembly  100  also includes electrical connector  120 . Electrical connector  120  may include a high density connector shell, such as a MICROPAX® connector. Connector  120  has forward end that mates with a matching connector assembly. Connector  120  also has a rearward, or cable, end. In one embodiment, the cable end of connector  120  accepts two paddleboards,  180  and  185 . Paddleboards  180  and  185  are adapted for connecting to electrical conductors of a cable. For sake of clarity, the cable is not shown in the drawing. The cable may include multiple copper, aluminum, or other conductors. The cable may be soldered to paddleboards  180  and  185 . The cable enters the backshell assembly via cable orifice  170 , shown here in the back wall of the housing. The cable may enter the backshell assembly on another wall of the assembly.  
         [0037]    In one embodiment, connector  120  is encircled with shell holder  125 . Shell holder  125  is fabricated of insulative material. In one embodiment, shell holder  125  is plastic. In one embodiment, shell holder  125  is fabricated of DELRIN® or TEFLON®, both registered trademarks of E. I. DU PONT DE NEMOURS AND COMPANY, 1007 Market St., Wilmington, Del. Connector  120  is received in a cavity of shell holder  125  and, in the embodiment shown, paddleboards  180  and  185  extend in a direction opposite that of mating face  115 . Paddleboards  180  and  185  provide a ground connection to maintain signal integrity pursuant to the standards of the HIPPI-6400 specification. Shell holder  125  provides physical spacing between the signal conductors of the cable and the connector relative to housing  110  sufficient to attenuate EMI radiation through housing  110 . Shell holder  125  also provides electrical isolation between the signal conductors and the housing to meet EMI standards for HIPPI-6400 connector assemblies.  
         [0038]    In one embodiment, shell holder  125  is coupled securely to shell holder base  145 . In one embodiment, base  145  is in slidable contact with the interior surface of the bottom of housing  110 . Base  145  is shaped to fit within the bottom of housing  110  and allow shell holder  125  to slide linearly within housing  110 . In one embodiment, base  145  includes an ear  140  on each side. Each ear  140  is in contact with an interior side wall of housing  110 . In one embodiment, mechanical stops provide limits to the forward and rearward movement of shell holder  125  within housing  110 . In one embodiment, the rearward limit is established by the compressed length of spring  135 . In one embodiment, the forward movement of shell holder  125  is limited by stop  190  securely attached to housing  110 . Alternatively, the forward movement of shell holder  125  is limited by the spring in the relaxed position. In one embodiment, the forward and rearward limits of shell holder  125  are established by a slot in shell holder base  145 . A pin, stud, or screw engaging the slot prevents movement of shell holder  125  beyond the forward and rearward limits. In the embodiment shown in the figure, stop  190  provides a mechanical limit to the forward travel of shell holder  125 . In one embodiment, shell holder  125  travels on a longitudinal axis of housing  110  in a way. The way may include formed linear sections of housing  110  which are engaged by complementary elements of shell holder  125 . In another embodiment, shell holder  125  is captivated by, and moves in, ways formed by structure within housing  110 . Such structure may include the springs  135 , clamping screws, or jackscrews,  230 , the interior sidewalls of housing  110 , or any other such structure.  
         [0039]    In one embodiment, a pair of jackscrews extend forward alongside connector  120 . Each jackscrew has a thread portion  130 , a head  165 , and a shoulder  160  positioned between thread end  130  and head  165 . In the embodiment shown, shoulder  160  is the underside of head  165 . In one embodiment, shoulder  165  is a larger diameter portion adjacent to a smaller diameter portion. The threads on thread end  130  correspond with threads on a standoff associated with a matching connector coupled to an electronic circuit housing.  
         [0040]    Proper mating of connector  120  with a matching connector entails establishing electrical connection as well as engaging the threads of the jackscrew with the threaded standoff.  
         [0041]    In one embodiment, the jackscrews pass through the interior of housing  110 . In one embodiment, the jackscrews are external to housing  110 . In the embodiment shown, the jackscrews pass through the back wall of housing  110 .  
         [0042]    Springs  135  provide a force urging shell holder  125  in the forward direction. In one embodiment, spring  135  is a wound tension spring threaded on a jackscrew. In the embodiment shown, spring  135  is captivated by structural elements within housing  110 . Structural elements may include counterbores, studs, raised portions or other means of captivating spring  135 . In the embodiment shown, two jackscrews and two springs are depicted. The present system may include a single jackscrew or more than two jackscrews. In various embodiments, the present system includes a single spring or more than two springs. Preloading of spring  135  urges a low impedance connection of connector  120  with the matching connector.  
         [0043]    Alternatively, rearward movement of the shell holder  125  may be limited by a threaded fastener engaging the threads of the jackscrew. For example, in an embodiment having two jackscrews, a threaded nut on each jackscrew may be used to captivate, and restrict the movement of, shell holder  125 . Other means of limiting the rearward movement of shell holder  125  are also contemplated.  
         [0044]    [0044]FIG. 1B depicts a view of the present system when mated to a matching MICROPAX® connector. The matching connector is represented by items  305 A and  305 B, shown herein associated with electrical housing  300 . Housing  300  is electrically conductive. Gasket  290  is positioned between mating face  115  of connector housing  110  and housing  300 . Gasket  290  includes a center opening to allow coupling of connector  120  with matching connectors  305 A and  305 B. Gasket  290  attenuates EMI radiation and provides a low impedance electrical connection between housing  110  and housing  300 . In the figure, insulative shell holder  125  is encased by electrically conductive housing  110 . As shown, connector  120  mates with matching connectors  305 A and  305 B.  
         [0045]    In one embodiment, proper assembly of the connector  120  to matching connector  305 A and  305 B includes engagement of a jackscrew (not visible in the figure). Gasket  290  is compressed by the force exerted by the jackscrew. Compression of gasket  290  reduces the impedance between face  115  and housing  300 . Compression also increases EMI attenuation at the interface of face  115  and housing  300 .  
         [0046]    [0046]FIG. 2 depicts an isometric view of a portion of one embodiment of the present system. In the embodiment shown, shell holder  125  is affixed to shell holder base  145 . Shell holder  125  includes holes  195  on either side of paddleboards  180  and  185 . Hole  195  receives a jackscrew. In addition, a spring (not shown in this figure) exerts a force on the rearward face of shell holder  125 .  
         [0047]    Paddleboards  180  and  185  receive conductors of the cable and provide an interface with connector  120 . Paddleboard  185  is shown herein as having a length less than paddleboard  180 , however the present system is not so limited and the relative lengths can be otherwise. In one embodiment, the cable includes copper conductors, each of which is bonded to conductors of paddleboard  180  or  185 . In one embodiment, bonding includes soldering conductors to the connector.  
         [0048]    Cavity  200  receives paddleboards  180  and  185  and connector  120 . Cavity  200  is shown herein as a rectangular hole in shell holder  125 , however, other configurations are also contemplated.  
         [0049]    As noted above, shell holder  125  is fabricated of insulative material. In one embodiment, shell holder  125  is fabricated of a material selected for having properties that reduces capacitive coupling between the connector and the backshell housing.  
         [0050]    Base  145  includes cars  140 . Ears  140  maintain alignment of shell holder  125  within housing  110 . Shell holder base  145  also is shown herein having slot  210  aligned substantially parallel with the direction of movement of shell holder  125 . Slot  210  maintains alignment of shell holder  125  and provides mechanical limits to the travel of shell holder  125 .  
         [0051]    [0051]FIG. 3 depicts another view of one embodiment of connector  120 , shell holder  125 , paddleboard  180 , paddleboard  185 , and shell holder base  145 . The boundaries of cavity  200  are visible as a hidden line within shell holder  125 . Ear  140  appears on the rearward portion of base  145 . In the embodiment shown, paddleboards  180  and  185  extend forward through shell holder  125  and are integral with connector  120 .  
         [0052]    [0052]FIG. 4 depicts a view of another embodiment of present system  100 . In the embodiment shown, electrically conductive backshell  110  provides a housing for connector  120  and various associated components. An electrical cable enters the housing at opening  170  and terminates at the conductor  120 . Electrical connection to the connector  120 , in the embodiment shown, is established by means of a pair of paddleboards. Paddleboard  185  is visible in the figure and a second paddleboard is obscured by the first. Shell holder base  145  is coupled to shell holder  125  (with connector  120 ) and moves fore and aft as limited by slot  210  and screw  215 . Spring  135  exerts a forward force on shell holder  125 . A first end of spring  135  is in contact with shell holder  125  and a second end of spring  135  is in contact with standoff  225 . Standoff  225  is in contact with an interior wall of housing  110  and spring  135  at face  220 . Spring  135 , and standoff  225  are concentrically aligned with jackscrew  230 . Jackscrew  230  includes head  165  for manual manipulation of jackscrew  230 . Head  165  also contacts housing  110  and exerts a clamping force to secure face  115  of housing  110  to an electrical housing associated with a matching connector.  
         [0053]    [0053]FIG. 5 illustrates another embodiment of the present system. Housing  110  includes mating face  115  at a forward end and cable orifice  170  at a rearward end. Connector shell  120  extends forward of shell holder  125 . Electrical connections to electrical connector  120  are via paddleboard  185  and paddleboard  180 . Shell holder base  145  extends rearward from shell holder  125  into housing  110 . Base  145 , in the embodiment shown, includes ears  140  that slidably engage structure  220  of housing  110  to limit the forward movement of shell holder  125  and connector  120 . Ears  140  also help maintain alignment of shell holder  125  in housing  110 .  
         [0054]    Spring  135  is held captive on the shaft of jackscrew  230  and exerts an opposing force on shell holder  125  and housing structure  220 . Engagement of thread end  130  of jackscrew  230  results in a clamping force applied to housing  110  at shoulder  160 . Face  115  is forced against the gasket  290  by jackscrew  230 .  
         [0055]    In the embodiment shown in FIG. 5, the cable exits housing  110  at an angle relative to the longitudinal axis. The longitudinal axis is parallel with the direction of travel of connector  120 . In other embodiments, the cable exits the housing at an angle substantially parallel with the longitudinal axis.  
         [0056]    [0056]FIGS. 6A, B and C illustrate another embodiment of the system of FIG. 5. In the figures, connector housing  110 B includes a metal housing having walls and a bottom surface. Housing connector lid  110 A is fastened to housing  110 B. Lid  110 A is fastened to housing  110 B by means of threaded fasteners, rivets, drive screws or other means.  
         [0057]    In the embodiment shown, shell holder  125  is depicted as a two-part assembly including shell holder  125 A and shell holder  125 B. Shell holder  125 B includes a cavity shaped to receive connector  120 , herein depicted as including the MICROPAX® shell. Shell holder  125 A includes a cover plate to secure shell  120  within holder  125 B. Shell holder  125 A and shell holder  125 B each include two holes  310  for accepting threaded fasteners. In one embodiment, connector  120  is sandwiched between shell holder  125 A and  125 B using two machine screws and two nuts.  
         [0058]    [0058]FIG. 7 illustrates another embodiment of the present system. FIG. 7A shows a connector housing lid  110 A having cable orifice  170  and mating face  115 . Lid  110 A is of cast aluminum construction having raised webs, or ridges as indicated at items  320  and thickened sections as indicated at  325 . In addition to providing structural reinforcement and strength, the ridges and thickened sections, in conjunction with the walls of housing  110 B (FIG. 7B), provide an improved EMI seal. Also visible in FIG. 7A are cable sealing members  330 . Cable sealing members  330  are further described with respect to FIG. 9 and are captivated by the webs and thickened sections of lid  110 A.  
         [0059]    [0059]FIG. 7B illustrates housing  110 B having cable orifice  170  and mating face  115 . Housing  110 B has wall sections including a plurality of threaded holes  340  for attachment of lid  110 A using machine screws. Holes  345  are clearance holes for the shaft of jackscrew  230 . Cable sealing members  330  are captivated by the walls of housing  110 B.  
         [0060]    In both FIG. 7A and FIG. 7B, ridge  350  is aligned transverse with respect to the longitudinal axis. Ridge  350  provides reinforcement and prevents substantial movement of the connector  120 . Connector  120 , and shell holder  125 A and  125 B are held securely relative to lid  110 A and housing  110 B.  
         [0061]    Connector shell holder sections  125 A and  125 B are illustrated in FIGS. 7C and 7D, respectively. Sections  125 A and  125 B are adapted to fit within lid  110 A and housing  110 B, respectively. Alignment groove  355 , visible as hidden lines in each of sections  125 A and  125 B, mates with ridge  350  in lid  110 A and housing  110 B. Holes  360  accept mechanical fasteners for securing connector  120  in the assembled shell holder sections  125 A and  125 B. Shell holder sections  125 A and  125 B are adapted to accept connector  120  in recess  370 . Clearance for the wall section near the two forward holes  340  in housing  110 B and lid  110 A are provided by notches  365 .  
         [0062]    [0062]FIG. 8 illustrates one embodiment of connector  120 , including a shell, suitable for use with the present system. FIGS. 8A, 8B and  8 C depict top view, end view and forward view, respectively of connector shell  120 . FIG. 8D depicts an isometric view of connector shell  120 . Shell  120  includes a pair of mounting holes  375  for securing connector shell  120  to shell holder  125 . In one embodiment, connector shell  120  is fabricated of cast, or machined, metal. In one embodiment, connector shell  120  is available from Berg Technology, Inc., One East First Street Reno, Nev. 89501 and is known in the trade as a MICROPAX® connector shell.  
         [0063]    [0063]FIG. 9 illustrates alternative cable sealing means. FIG. 9A provides a forward view of the backshell assembly, as viewed from the rear. Visible in the figure are jackscrew heads  165 . Also visible is cable orifice  170 . In one embodiment, housing  110  includes a sealing surface  395 . In the embodiment shown, the sealing surface  395  is lined with cable sealing, or packing material  380 . Cable packing material  380  may be a woven or non-woven conductive metal material in the form of a coiled strip. A rivet may be used to secure the cable packing material  380  to sealing surface  395 .  
         [0064]    In FIG. 9B, cable sealing members  330  are illustrated, each having semicircle  385 . Sealing members  330  are fabricated of conductive metal and are adapted to fit securely in the webs and thickened sections of lid  110 A and housing  110 B of FIGS. 7A and 7B, respectively. Sealing material  380  is a woven or non-woven conductive metal material in the form of a coiled strip.  
       Conclusion  
       [0065]    Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement which is calculated to achieve the same purpose may be substituted for the specific embodiment shown. This application is intended to cover any adaptations or variations of the present invention.