Abstract:
The invention provides for an electrical connector including first and second housings having mating ends configured to be joined with one another and retain contacts that are joined when the first and second housings are mated. The first and second housings each have a reception end receiving a dielectric subassembly carrying an electrical cable connected to contacts. The dielectric subassemblies are aligned along a longitudinal axis and mate with one another when the first and second housings are mated. The first and second housings each have a hatch proximate a corresponding reception end that closes the reception end and engages a rear wall of the dielectric subassembly. At least one of the hatch and rear wall have a loading protrusion that engages another one of the hatch and rear wall to create a load force along the longitudinal axis to maintain the dielectric subassemblies fully mated with one another.

Description:
RELATED APPLICATIONS 
     This application is related to, and claims priority from, Provisional Application No. 60/360,280, filed Feb. 27, 2002, titled “Electrical Connector Assembly for Coaxial Cables,” the complete subject matter of which is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     Certain embodiments of the present invention relate to connector assemblies that electrically interconnect coaxial cables. More particularly, certain embodiments of the present invention relate to connector assemblies that preload dielectrics within matable housings such that the dielectrics are in full mating contact with each other when connected. 
     In the past, connectors have been proposed for interconnecting coaxial cables. Generally, coaxial cables have a circular geometry formed with a central conductor (of one or more conductive wires) surrounded by a cable dielectric material. The dielectric material is surrounded by a cable braid (of one or more conductive wires) that serves as a ground, and the cable braid is surrounded by a cable jacket. In most coaxial cable applications, it is preferable to match the impedance between source and destination electrical components located at opposite ends of the coaxial cable. Consequently, when sections of coaxial cable are interconnected by connector assemblies, it is preferable that the impedance remain matched through the interconnection. 
     Today, coaxial cables are widely used. Recently, demand has arisen for radio frequency (RF) coaxial cables in applications such as the automotive industry. The demand for RF coaxial cables in the automotive industry is due in part to the increased electrical content within automobiles, such as AM/FM radios, cellular phones, GPS, satellite radios, Blue Tooth™ compatibility systems and the like. The wide applicability of coaxial cables demands that connected coaxial cables maintain the impedance at the interconnection. 
     Conventional coaxial connector assemblies include matable plug and receptacle housings carrying dielectric subassemblies. The dielectric subassemblies include dielectrics, metal outer shields, and center contacts. The dielectric subassemblies receive and retain coaxial cable ends, and the outer shields have pins that pierce the jackets to electrically contact the cable braids while the center contacts engage the central conductors. The plug and receptacle housings include interior latches that catch and hold the dielectric subassemblies, and thus the coaxial cable ends, therein. When the plug and receptacle housings are mated, the dielectric subassemblies are engaged such that the outer shields are interconnected and the center contacts are interconnected with the dielectrics interconnected therebetween to form a dielectric between signals sent through the outer shields and signals sent through the center contacts. 
     The conventional coaxial connector assembly suffers from certain drawbacks. The interior latches allow the dielectric subassemblies to axially float within the plug and receptacle housings. When the plug and receptacle housings are mated, the dielectric subassemblies have a certain longitudinal clearance in order that the mated dielectric subassemblies separate slightly from each other without being disconnected or interrupting the electrical connection. When such a separation occurs, the dielectrics are disengaged to a point that air gaps develop between the connected center contacts and the connected outer shields. Because the air gaps have a different dielectric constant than the dielectrics and cable dielectric material, the impedance experienced by the electric signals changes at the point where the dielectric subassemblies interconnect. The change in impedance causes the electric signals to reflect at the point of interconnection, so more power is required to electrically connect the coaxial cables. 
     Thus, an improved coaxial connector assembly is needed that avoids the above noted problems and other disadvantages experienced heretofore. 
     BRIEF SUMMARY OF THE INVENTION 
     Certain embodiments of the present invention include an electrical connector assembly including first and second housings having mating ends configured to be joined with one another and configured to retain contacts that are joined when the first and second housings are mated. The first and second housings each have a reception end receiving a dielectric subassembly configured to carry an electrical cable connected to a contact. The dielectric subassemblies are aligned along a common longitudinal axis and mate with one another when the first and second housings are mated. Each of the first and second housings have a hatch proximate a corresponding reception end. The hatch closes the corresponding reception end and engages a rear wall of the dielectric subassembly. A load protrusion is provided on at least one of the hatch and rear wall. The load protrusion resistibly engages another one of the hatch and rear wall to create a load force along the longitudinal axis that maintains the dielectric subassemblies fully mated with one another. 
     Certain embodiments of the present invention include an electrical connector including a housing having a reception and a mating end opposite one another along a longitudinal axis of the housing. The electrical connector includes a dielectric subassembly configured to carry, and electrically connect to, an electrical cable. The dielectric subassembly is slidably received in an opening in the reception end of the housing. The electrical connector includes a hatch mounted to the housing proximate the reception end. The hatch closes the reception end and engages a rear wall of the dielectric subassembly. At least one of the hatch and the rear wall have a loading protrusion mounted thereon. The loading protrusion applies a binding load force biasing the dielectric subassembly along the longitudinal axis toward the mating end. 
    
    
     BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS 
     FIG. 1 illustrates a top isometric view of an electrical connector assembly according to an embodiment of the present invention. 
     FIG. 2 illustrates an exploded isometric view of a plug housing, coaxial cable, and dielectric subassembly according to an embodiment of the present invention. 
     FIG. 3 illustrates an isometric view of the coaxial cable and dielectric subassembly partially inserted into the plug housing. 
     FIG. 4 illustrates an isometric view of the coaxial cable and dielectric subassembly fully inserted into the plug housing. 
     FIG. 5 illustrates a bottom isometric view of the coaxial cable and dielectric subassembly fully inserted into the plug housing. 
     FIG. 6 illustrates an exploded isometric view of a receptacle housing, coaxial cable, and dielectric subassembly according to an embodiment of the present invention. 
     FIG. 7 illustrates an isometric view of the coaxial cable and dielectric subassembly partially inserted into the plug housing. 
     FIG. 8 illustrates an isometric view of the coaxial cable and dielectric subassembly partially inserted into the receptacle housing. 
    
    
     The foregoing summary, as well as the following detailed description of certain embodiments of the present invention, will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings, certain embodiments. It should be understood, however, that the present invention is not limited to the arrangements and instrumentality shown in the attached drawings. 
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 illustrates a top isometric view of an electrical connector assembly  8  according to an embodiment of the present invention. The electrical connector assembly  8  includes a plug housing  10  and a receptacle housing  12  that each carry a coaxial cable  16 . The receptacle housing  12  slidably receives the plug housing  10  to electrically connect the coaxial cables  16 . The plug and receptacle housings  10  and  12  are maintained in mating contact by a deflectable latch  40  extending from a top wall  32  of the plug housing  10 . When the plug housing  10  is slidably inserted into the receptacle housing  12  in the direction of arrow A, the deflectable latch  40  is biased in the direction of arrow B such that the deflectable latch  40  slides under a retention strip  18  of the receptacle housing  12  into a gap  22 . The plug housing  10  is fully inserted into the receptacle housing  12  when the deflectable latch  40  is positioned in the gap  22  and laterally engages the retention strip  18 . To disengage the plug and receptacle housings  10  and  12 , the deflectable latch  40  is again biased inward by pushing a latch beam  44  in the direction of arrow B, and the plug housing  10  is slidably removed from the receptacle housing  12  in the direction of arrow C until the deflectable latch  40  no longer engages the retention strip  18 . 
     FIG. 2 illustrates an exploded isometric view of the plug housing  10 , the coaxial cable  16 , and a dielectric subassembly  14  according to an embodiment of the present invention. The plug housing  10  is defined by opposite side walls  28  formed with top and bottom walls  32  and  36  that include a mating end  20  and a reception end  24 . The top wall  32  includes the deflectable latch  40  and latch beam  44 . The bottom wall  36  includes an A-shaped prong  120  with guide beams  84  extending inward within the plug housing  10 . The guide beams  84  are aligned with, and slidably receive, the dielectric subassembly  14  along a rear wall  50  as the dielectric subassembly  14  is inserted into the plug housing  10 . The guide beams  84  properly orient and retain the dielectric subassembly  14  within the plug housing  10 . 
     The bottom wall  36  also includes hinges  52  that extend to an opened hatch  56  that is perpendicular to the bottom wall  36 . Retention latches  60  extend perpendicularly from the hatch  56  opposite each other. The retention latches  60  slide over sloped faces  62  of latch catches  64  extending from the side walls  28  and receive the latch catches  64  when the hatch  56  is rotated 180 degrees in the direction of arrow D to close the reception end  24 . The hatch  56  also includes cylindrical loading protrusions  68  that extend outward from an interior surface  72  of the hatch  56 . The loading protrusions  68  are formed of plastic or any other resilient material and engage and resist a rear wall  70  of the dielectric subassembly  14  when the dielectric subassembly  14  is loaded within the plug housing  10 . Additionally, the hatch  56  includes a gap  76  leading to a cable hole  80  through which the coaxial cable  16  extends when positioned within the plug housing  10  and the dielectric subassembly  14 . 
     The dielectric subassembly  14  includes a plastic dielectric  88  connected to a rectangular metal outer shield  92 . The dielectric subassembly  14  receives and retains the coaxial cable  16 . The coaxial cable  16  includes a central conductor  96  concentrically surrounded by a dielectric material  100  which in turn is concentrically surrounded by a cable braid  104  that serves as a ground pathway. The dielectric  88  includes a leading portion  114  that engages catches (not shown) on the side walls  28  inside the plug housing  10  that retain the dielectric subassembly  14  therein. The outer shield  92  includes conductive pins (not shown) that extend into the cable braid  104  to join the ground pathway. The outer shield  92  also includes anti-stubbing members  112  extending from a side wall  116  proximate an interface end  108  of the dielectric assembly  14 . The anti-stubbing members  112  engage corresponding anti-stubbing members  238  (FIG. 6) on a dielectric subassembly  150  of the receptacle housing  12  such that the outer shield  92  overlaps an outer shield  234  (FIG. 6) on the dielectric subassembly  150 . The outer shield  92  also includes an S-shaped locking member (not shown) on a side wall  116 . The locking member engages a mating outer shield  234  (FIG. 6) near an end of the outer shield  234  of the dielectric subassembly  150 . Likewise, the outer shield  234  includes an S-shaped latching member (not shown) on a side wall  242  (FIG. 6) of the dielectric assembly  150 . The locking member on the side wall  242  engages the outer shield  92  near an end of the outer shield  92 . The locking members engage each other and hold the outer shields  92  and  234  in contact by maintaining a constant normal force between the outer shields  92  and  234 . 
     A contact tab (not shown) within the dielectric subassembly  14  engages the conductor  96  of the coaxial cable  16  to join the electric signal pathway. A rectangular front portion (not shown) extends from the dielectric  88  and separates the contact tab and the outer shield  92  at the interface end  108 . The dielectric constant of the front portion is similar to the dielectric constant of the dielectric material  100  in order to maintain a constant impedance between the interconnected coaxial cables  16  and thus prevent the reflection of electric signals traveling along the coaxial cables  16 . 
     In operation, as shown in FIG. 3, the dielectric subassembly  14  retaining the coaxial cable  16  is inserted in the direction of arrow E into the plug housing  10 . When the dielectric subassembly  14  is fully inserted into the plug housing  10  as shown in FIG. 4 such that the leading portions  114  (FIG. 2) are resisted by the catches of the side walls  28 , the hatch  56  is closed by rotating about the hinges  52  in the direction of arrow D. As the hatch  56  is closed, the coaxial cable  16  is pinched within the gap  76  and slides therethrough into the cable hole  80 . Additionally, as the hatch  56  is closed, the retention latches  60  slide along the side walls  28  and deflect outward away from each other about the sloped faces  62  until receiving the latch catches  64 , thus holding the hatch  56  closed about the dielectric subassembly  14 . 
     FIG. 5 illustrates a bottom isometric view of the coaxial cable  16  and dielectric subassembly  14  fully inserted into the plug housing  10 . The prong  120  extends from the bottom wall  36  of the plug housing  10  along the guide beams  84  toward the reception end  24 . The prong  120  is separated from the side walls  28  by slots  132 , and a gap  136  extends between the guide beams  84  along the center of the bottom wall  36 . A latch  140  extends from the rear wall  50  of the dielectric subassembly  14  into the gap  136  and engages the prong  120 . Thus, as the dielectric subassembly  14  is inserted into the plug housing  10 , the latch  140  slides along the prong  120  and deflects the prong  120  in the direction of arrow J until the latch  140  enters the gap  136 . Once the latch  140  is in the gap  136  and pushing against the prong  120  in the direction of arrow L, the dielectric subassembly  14  is initially retained within the plug housing  10  and the hatch  56  is closed. Alternatively, to release the dielectric subassembly  14 , the latch  140  is biased in the direction of arrow F until no longer engaging the prong  120 , and the dielectric subassembly  14  is slid in the direction of arrow L. 
     Returning to FIG. 4, when the hatch  56  is rotated to close the reception end  24 , the loading protrusions  68  engage and push against the rear wall  70  of the dielectric  88  in the direction of arrow E. Because the dielectric  88  is formed of a harder plastic than the loading protrusions  68  or the hatch  56 , the dielectric  88 , which is braced against the catches on the side walls  28 , resists the pressure of the loading protrusions  68  and the hatch  56  in the direction of arrow L, causing the loading protrusions  68  to compress and the hatch  56  to slightly buckle outward along the longitudinal axis  113 . The loading protrusions  68  thus deliver a load force along a longitudinal axis  113  against the hatch  56  and the rear wall  70  such that the dielectric subassembly  14  is preloaded within the plug housing  10  between the catches on the side walls  28  and the loading protrusions  68 . Because of the pressure of the load force delivered by the loading protrusions  68 , the dielectric subassembly  14  does not float along the longitudinal axis  113 . The plug housing  10  is then mateably received by the receptacle housing  12  (FIG. 1) to electrically connect the coaxial cables  16 . 
     The hatch  56  is opened by pulling the retention latches  60  outward in opposite directions away from each other such that the retention latches  60  clear the latch catches  64 , and then rotating the hatch  56  in the direction of arrow M about the hinges  52 . In an alternative embodiment, the loading protrusions  68  are connected to the rear wall  70  of the dielectric  88  to resistibly engage the hatch  56  as the hatch  56  is closed about the reception end  24 . 
     FIG. 6 illustrates an exploded isometric view of the receptacle housing  12 , the coaxial cable  16 , and a dielectric subassembly  150 . The receptacle housing  12  is defined by opposite side walls  154  formed with top and bottom walls  158  and  162  that include a mating end  166  and a reception end  170 . The top wall  158  includes a prong  174  extending toward the reception end  170  and separated from the side walls  154  by slots  178 . The prong  174  slides along a top wall  182  of the dielectric subassembly  150  as the dielectric subassembly  150  is inserted into the receptacle housing  12  and slidably enters a pocket  188  proximate the rear wall  186  of the dielectric subassembly  150  when the dielectric subassembly  150  is fully inserted into the receptacle housing  12 . The top wall  158  also includes the gap  22  and retention strip  18  that retain the deflectable latch  40  of the plug housing  10  (FIG.  1 ). 
     The bottom wall  162  includes hinges  190  that extend to an opened hatch  194 , similar to the plug housing  10  of FIG.  2 . Retention latches  198  extend perpendicularly from the hatch  194  opposite each other. The retention latches  198  slide over sloped faces  202  of latch catches  206  extending from the side walls  154  and receive the latch catches  206  when the hatch  194  is rotated 180 degrees in the direction of arrow N to close the reception end  170 . The hatch  194  also includes cylindrical loading protrusions  210  that extend outward from an interior surface  214  of the hatch  194 . The loading protrusions  210  are formed of plastic or any other resilient material and engage and resist the rear wall  186  of the dielectric subassembly  150  when the dielectric subassembly  150  is loaded within the receptacle housing  12 . Additionally, the hatch  194  includes a gap (not shown) leading to a cable hole  226  through which the coaxial cable  16  extends when positioned within the receptacle housing  12  and the dielectric subassembly  150 . 
     The dielectric subassembly  150  includes a plastic dielectric  230  connected to the rectangular metal outer shield  234 . The dielectric  230  includes a leading portion  248  that engages catches (not shown) on the side walls  154  inside the receptacle housing  12  that retain the dielectric subassembly  150  therein. The outer shield  234  includes conductive pins (not shown) that extend into the cable braid  104  of the coaxial cable  16  to join the ground pathway. The outer shield  234  also includes the anti-stubbing members  238  extending from a side wall  242  proximate an interface end  246  of the dielectric assembly  150  and the S-shaped locking member (not shown) extending from the opposite side wall  243 . A contact tab (not shown) within the dielectric subassembly  150  engages the central conductor  96  of the coaxial cable  16  to join the electric signal pathway. A rectangular front portion  250  extends from the dielectric  230  and separates the contact tab and the outer shield  234  at the interface end  246 . The front portion  250  maintains the dielectric constant between the interconnected coaxial cables  16  shown in FIG.  1 . 
     In operation, as shown in FIG. 7, the dielectric subassembly  150  retaining the coaxial cable  16  is positioned in the direction of arrow P into the receptacle housing  12 . FIG. 8 illustrates a top isometric view of the coaxial cable  16  and the dielectric subassembly  150  partially inserted into the receptacle housing  12 . The dielectric subassembly  150  is fully inserted into the receptacle housing  12  when the leading portions  248  (FIG. 6) are resisted by the catches of the side walls  154 , preventing the dielectric subassembly  150  from being further inserted into the receptacle housing  12 . The hatch  194  is then closed by rotating about the hinges  190  (FIG. 6) in the direction of arrow N. As the hatch  194  is closed, the coaxial cable  16  is pinched within the gap and slides therethrough into the cable hole  226 . Additionally, as the hatch  194  is closed, the retention latches  198  slide along the side walls  154  and deflect outward away from each other about the sloped faces  202  (FIG. 6) until receiving the latch catches  206  (FIG.  6 ), thus holding the hatch  194  closed about the dielectric subassembly  150 . 
     When the hatch  194  is rotated to close the reception end  170 , the loading protrusions  210  engage and push against the rear wall  186  in the direction of arrow P such that the dielectric subassembly  150  is firmly retained within the receptacle housing  12 . Because the dielectric  230  is formed of a harder plastic than the loading protrusions  210  or the hatch  194 , the dielectric  230 , which is braced against the catches on the side walls  154 , resists the pressure of the loading protrusions  210  and hatch  194  in the direction of arrow S, causing the loading protrusions  210  to compress and the hatch  194  to slightly buckle. The loading protrusions  210  thus deliver a load force along a longitudinal axis  280  against the hatch  194  and the rear wall  186  such that the dielectric subassembly  150  is preloaded within the receptacle housing  12  between the catches on the side walls  154  and the loading protrusions  210 . Because of the pressure of the load force delivered by the loading protrusions  210 , the dielectric subassembly  150  does not float along the longitudinal axis  280 . 
     The hatch  194  is opened by pulling the retention latches  198  outward in opposite directions away from each other such that the retention latches  198  clear the latch catches  206  (FIG.  6 ), and then rotating the hatch  194  in the direction of arrow T about the hinges  190  (FIG.  6 ). In an alternative embodiment, the loading protrusions  210  may be connected to the rear wall  186  of the dielectric  230  to resistibly engage the hatch  194  as the hatch  194  is closed about the reception end  170 . 
     The receptacle housing  12  mateably receives the plug housing  10  to electrically connect the dielectric subassemblies  14  (FIG. 2) and  150 . As the preloaded dielectric subassemblies  14  and  150  are connected within the receptacle housing  12 , the outer shields  234  and  92  (FIG. 2) are electrically engaged and held together by the locking members and the central conductors  96  of the coaxial cables  16  are electrically connected via the center contacts. Similarly, the dielectrics  88  and  230  engage each other between the connected outer shields  234  and  92  and the connected center contacts, thus forming a dielectric barrier therebetween. Because the dielectric subassemblies  14  and  150  are prevented from axially floating by the loading protrusions  68  (FIG. 2) and  210 , respectively, the dielectric subassemblies  14  and  150  are fully engaged so air gaps do not develop between the connected outer shields  234  and  92  and the connected center contacts. Thus, the impedance experienced by the electric signals passing from one coaxial cable  16  to another is not altered where the coaxial cables  16  interconnect and less electrical power is necessary to effectively send the electric signals between the coaxial cables  16 . 
     While the invention has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.