Patent Publication Number: US-8113879-B1

Title: One-piece compression connector body for coaxial cable connector

Description:
FIELD OF THE INVENTION 
     The application relates generally to the field of coaxial-type cable connectors and more specifically to a coaxial cable compression connector for terminating a prepared coaxial cable end in which a compression member is integrally provided as part of the connector body. 
     BACKGROUND OF THE INVENTION 
     Coaxial cable connectors are commonly used with a terminated coaxial cable end for connection to various components, such as those in CATV and broadband applications including attachment to appliances such as computers, televisions and the like. The terminal end of a coaxial cable is typically retained by means of a compression member acting in concert with a connector body into which the cable end is introduced. 
     One common type of coaxial cable connector useful for the above purposes is defined by a number of elements that include a hollow post, a coupling nut, a connector body and a compression sleeve or other member. A typical example of such a connector is described in commonly owned and assigned U.S. Pat. No. 6,716,062. The connector body, post and compression sleeve according to this typical design are individual and separate components that permit the end of a coaxial cable to be secured and wherein the nut is connected to the flanged end of the post and is freely rotatable to permit attachment, for example, to an external port, such as found on an appliance. 
     According to this version, the connector body is acted upon by the compression sleeve which is axially displaced over the exterior of the connector body. The compression sleeve is defined by an axial section having an inner diameter that is smaller than the exterior diameter of the connector body to effect radial deformation thereof and produce retention of the prepared cable end. 
     There is a general need to facilitate the manufacturability of the above-noted connectors. To that end, one attempt at integrating the connector body and compressive sleeve is described in commonly owned U.S. Pat. No. 6,780,052 B2. Two embodiments are described in this patent. According to a first embodiment, a proximal portion of the connector body is caused to fracture wherein the fractured portion is further caused to move inwardly within the connector body as a wedge. In a second embodiment, the connector body or at least a portion thereof is made from a highly flexible material that is readily deformable. As axial force is applied, a portion of the connector body is then caused to fold upon itself to create a retaining chamber. Another attempt at integration of a compressive member in a coaxial cable connector is described in U.S. Pat. No. 7,125,283. This latter patent still requires the use of separate components, including an exterior sleeve as well as an independent locking ring. 
     Each of the foregoing patents provide techniques for creating compression in order to retain a prepared coaxial cable end for termination, but involve variations to those previously employed when separate components are used. It would be preferred to simplify the design of currently known compression connectors of the above type, while still reliably providing the same form of cable compression technique. 
     SUMMARY OF THE INVENTION 
     According to one aspect, there is provided a connector body for a coaxial cable connector, said connector body being defined by a hollow member having opposing ends, said connector body including a first body section and an axially adjacent second body section, said first body section being radially deformable, wherein compressive axial force applied upon said second end of said connector body causes said second body section to fracture relative to said first body section, said second body section being caused to move over the exterior surface of said first body section and form a compression sleeve. 
     In one version, the interior surface of the first body section includes an inwardly ramped surface wherein movement of the first body section over the second body section causes radial deformation of the first body section to permit retention of an installed cable end. 
     In one version, a weakened or frangible area is created between the first and second body sections that is caused to fracture upon application of the axial force, thereby allowing the movement of the second body section over the exterior of the first body section. 
     According to another aspect, there is provided a coaxial cable connector comprising a coupling nut, a hollow post having a first end and a second end, said second end being configured for engaging the end of a coaxial cable end, and a connector body being defined by a hollow plastic member having opposing ends, said connector body including a first body section and an axially adjacent second body section wherein said second end of said hollow post is disposed within the first body section of said connector body, said first body section being radially deformable, wherein a compressive axial force applied upon said second end of said connector body causes said second body section to fracture relative to said first body section, said second body section being caused to move over the exterior surface of said first body section and form a compression sleeve. 
     In one version, the first and second body sections are separated by a weakened or frangible annular portion that is caused to fracture upon application of axial force upon said second body section, thereby allowing movement of the second body section over the exterior surface of the first body section. 
     The second body section can include an interior area tapering from a first inner diameter to a second smaller inner diameter such that axial movement of the second body section over the exterior surface of the first body section causes radial deformation thereof. At least a portion of the first body section can include a thin-walled cylindrical chamber made from a deformable material. 
     An advantage of the herein described connector is that the connector operates in substantially the same manner as previously known compression-type connectors, but with fewer components. 
     Another advantage realized herein is that the presently described connector provides cost reduction through conversion of a separately molded or fabricated part to a molded part of the connector body with no substantial impact on reliability. 
     These and other features and advantages will be readily apparent from the following Detailed Description, which should be read in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded assembly view of a prior art coaxial cable connector; 
         FIG. 2  is a side elevational view, taken in section, of the coaxial cable connector of  FIG. 1 , in an assembled condition; 
         FIG. 3  is a side perspective view of a coaxial cable connector in accordance with an exemplary embodiment of the present invention; 
         FIG. 4  is an exploded view of the coaxial cable connector of  FIG. 3 ; 
         FIG. 5  is a sectioned view of the connector body of the coaxial cable connector of  FIGS. 3 and 4  in a preassembled condition; and 
         FIG. 6  is a sectioned view of the coaxial cable connector of  FIGS. 3-5 , as shown in an assembled condition. 
     
    
    
     DETAILED DESCRIPTION 
     The following description relates to a preferred embodiment of a compression-type coaxial cable connector. More specifically, the herein described connector relates to a specific version of an F-type or F-connector, but it will be readily apparent that the herein described connector body with an incorporated or integrated compression ring or sleeve can be incorporated into other suitable compression-type connector designs, such as but not limited to, F-Type, RCA and BNC-type connectors. In addition, various terms are used throughout, such as “top”, “bottom”, “upper”, “lower” and the like in order to provide a suitable frame of reference with regard to the accompanying drawings. These conventions, however, are not intended to overly burden the intended scope of the herein described concepts, except in those instances where so specifically noted. 
     Reference is first made to  FIGS. 1 and 2  that depict a prior art compression connector, described herein for background purposes. 
     This coaxial cable connector is shown in  FIG. 1  in exploded form. The connector, hereinafter labeled with reference numeral  100 , is defined by an assemblage having a number of discrete components that can be operably affixed to the end of a coaxial cable  10 , the cable having a protective outer jacket or sleeve  12 , a conductive grounding shield  14 , an interior or intermediate dielectric layer  16  and a center conductor  18 . The coaxial cable  10  can be drawn back for purposes of termination, as represented in  FIG. 1 , by removing the protective outer jacket  12  and then drawing back the conductive grounding shield  14 , which may be braided, in order to expose an axial portion of the intermediate dielectric layer  16 . Additional preparation of the end of the coaxial cable  10  can include stripping or coring the intermediate dielectric layer  16  in order to expose a portion of the center conductor  18 . 
     The components, for purposes of this typical connector  100 , include a threaded nut  30 , a post  40 , a connector body  50 , a compression member or sleeve  60  and a connector body sealing member  80 , such as an O-ring. 
     A brief description of each of the components of the connector of  FIGS. 1 and 2  now follows: First, the threaded nut  30  according to this version is formed from an electrically conductive material, the nut having a first end  31  and an opposing second end  32 . A set of internal threads  33  extend from the edge of the first end  31  over a sufficient axial distance that permits effective threaded contact with the external threads  23  of a standard coaxial cable interface port  20  (shown partially in  FIG. 1 ). The nut  30  further includes an internal lip  34 , in this instance an annular protrusion, which is disposed proximate the second end  32 , therein defining a flange. 
     The post  40  is a rigidly formed body made according to this version from an electrically conductive material and defined by a first end  41  and an opposing second end  42 . A flange  44 , such as an externally extending annular protrusion, is located at the first end  41  of the post  40  and defined by an annular shoulder  45 . The post  40  further includes a hollow shaft portion  43  having a substantially constant and cylindrical cross section extending from the second end  42  to a tapering portion having at least one surface feature  47  that is intermediately disposed in relation to the first end  41 . When assembled, the post  40  is formed such that portions of the prepared coaxial cable end  10 , including the intermediate dielectric layer  16  and the center conductor  18 , are permitted to pass into the second end  42  through the shaft portion  43  while the outer jacket  12  and shielding layer  14  are caused to be stripped by the second end of the post, as described briefly below. 
     The connector body  50  includes a first end  51  and an opposing second end  52  that is substantially hollow and defined by a center passageway or bore. Adjacent the first end  51  of the connector body  50  is a post mounting portion  57  that is configured to mate with the at least one exterior surface feature  47  of the post  40 , enabling the post to be axially as well as radially secured to the connector body. The connector body  50  further includes an outer annular recess  58  located proximate the first end  51 , which enables the placement of the sealing member  80  as further confined by the second end  32  of the nut  30  proximal to the lip  34 . A portion  53  of the connector body  50  is formed from a semi-rigid, yet compliant outer surface  55 , this portion being configured to form an annular seal when the second end  52  is deformably compressed against a retained coaxial cable  10  by operation of the compression member  60 , as described in greater detail below. 
     The compression member  60  according to this known connector version is defined by a cylindrical sleeve-like section that further includes opposing first and second ends  61 ,  62 , respectively. The first and second ends  61 ,  62  are interconnected by means of a center passageway  65 , the passageway having a plurality of sections including a first diametrical section  67  adjacent the first end  61  having a first inner diameter and a second diametrical section  68  adjacent the second end  62  having a second inner diameter that is smaller than the first inner diameter. A transitional section  66 , provided intermediate the first and second diametrical sections  67 ,  68 , is defined by an interior ramped surface. 
     The herein described coaxial cable connector  10 , referring to  FIGS. 1 and 2 , serves to securably retain a prepared coaxial cable end  10  (the cable is not shown in  FIG. 2  for the sake of clarity). In this configuration, the prepared coaxial cable end  10 , including the extending axial section of the center conductor  18 , is inserted into the interior of the connector body  50  through the second end  52  thereof as well as through the center passageway  65  of the compression member  60 . The first end  42  of the post  40 , fitted and secured into the confines of the connector body  50  engages the coaxial cable end  10  between the cored dielectric layer  16  and the grounding shield layer  14 . According to this version, the compression member  60  is then axially advanced over the exterior of the connector body  50  by means of a compression tool (not shown) or otherwise, causing the interior ramped surface of the compression member  60  to engage and thereby compress the deformable outer portion  53  of the connector body  50  in a radial fashion inwardly and securing the coaxial cable end  10  within the connector  100 . The dielectric layer  16  and center conductor  18  are each advanced into the shaft portion  43  of the post  40 , while the outer sleeve  12  and the shielding layer  14  of the advanced coaxial cable  10  are additionally stripped by means of the post  40  and the action of the compression tool and the advancing compression member  60 , which passes axially over the exterior of the connector body  50 . 
     As noted, the post  40  is secured with the connector body  50  wherein the at least one exterior surface feature  47  of the post engages with the post mounting portion  57  of the connector body  50  to both axially and radially secure the post  40  in place. 
     In the meantime, the coupling nut  30  of the herein described coaxial connector  100  is secured to the post  40  and is mounted so as to permit free rotation, while the center conductor  18  extends through the first end  42  of the post  40  and outwardly from the coupling nut  30 . More specifically and according to this prior art version, the coupling nut  30  is permitted limited axial movement through rotation thereof, wherein the nut flange  34  is caused to engage directly with the annular flange  44  of the post  40  as the coupling nut  30  is engaged with an external interface port  20 . 
     External threads  23  of the external interface port  20  are then threadingly engaged with the internal threads  33  of the coupling nut  30  of the herein described connector  100 , causing the coupling nut  30  to be secured thereupon through limited axial movement of the threaded nut as the lip  34  of the nut engages the flange  44  of the post  40 . Electrical continuity is initiated based upon compressive contact that is created between the annular flange  44  of the post  40  and an end radial face of the interface port  20 , when the coupling nut  30  has been fully tightened. As noted and though effective, the above coaxial cable connector  10  relies upon specific tolerance matchups between the external interface port  20  and the coupling nut  30  of the coaxial cable connector  100  in order to properly provide an effective connection therebetween. There is no permissible variability for this herein described coaxial cable connector  100 , however, to accommodate various sized external interface ports. 
     With the preceding background and now referring to  FIGS. 3-6 , there is shown a compression-type coaxial cable connector made in accordance to the exemplary embodiment. The connector (herein labeled with the reference numeral  200 ) is an assemblage of components that include a connector body  220 , a hollow post  240  and a coupling nut  260 . Of significance and in contrast to the preceding, it should be noted that a separate compression sleeve or member is not required. 
     The connector body  220  according to this exemplary embodiment is made from a unitary one-piece construction from a plastic, such as Lexan or neoprene. The connector body  220  comprises a first end  222  and an opposing second end  223  wherein the body  220  is substantially hollow. More specifically, the connector body  220  is defined by a first body section  224  and an axially adjacent second body section  225 . The first body section  224  is a substantially cylindrical portion that includes a post retaining portion  228  formed at the first end  222  wherein a center aperture  230  extends into a necked portion  231  having a first internal diameter. The necked portion  231  extends proximally toward the second end  223  of the connector body  220  and terminates at an annular shoulder  232  forming a wall of an interior passageway  233 . The passageway  233  has a substantially constant second inner diameter that is larger than the first inner diameter of the necked portion  231 . The outer or exterior diameter of the first body section  224  is further defined by an annular flange  229  having a first exterior diameter adjacent the first end  222  that is larger than a cylindrical axial section  234  having a second end substantially constant exterior diameter over substantially the remainder of the first body section  224 . This latter axial section  234  is further defined by a relatively thin-walled construction as compared to, for example, that of the annular flange  229 . 
     The second body section  225  is defined by a substantially cylindrical cross section, this body section having a substantially constant exterior outer diameter that is approximately equivalent to that of the annular flange  229  of the first body section  224 . The distal end of the second body section  225  is joined to the proximal end of the thin-walled cylindrical axial portion  234  of the first body section  224 , wherein a slight overlap is created therebetween. 
     With further reference especially to  FIG. 5 , the second body section  225  is defined by a proximal diametrical portion  235  having a substantially constant first inner diameter adjacent the second end  223  of the connector body  220 , a distal diametrical portion  237  having a second inner diameter adjacent the distal end  229  of the second body section  225  that is larger than the first inner diameter of the proximal diametrical section  235  and a transitional portion  236  extending therebetween having a ramped interior surface. 
     As noted, the proximal end  227  of first body section  224  and the distal end  229  of the second body section  225  are molded with a slight overlap, see  FIG. 5 , and are frangibly connected to one another by a weakened annular portion  226 , forming a stress concentrator. 
     The hollow post  240  is defined by a first end  242  and an opposing second end  246 . A substantial portion of the post  240  is sized to be fitted within the confines of the connector body  220  and retained axially and rotationally by the post retaining portion  228  that engages a surface feature  248 ,  FIG. 5 , of the post. The first end  242  is defined by a flange  250  having a center aperture  249  as well as a radial end edge  251 . A shaft portion  253  of the post  240  is accommodated within the center passageway  233  of the connector body  220 . 
     The coupling nut  260  is defined by a first end  262  and an opposing second end  264 , as well as a set of internal threads  266  within a center passageway  265 . An interior lip or protrusion  270 , shown most clearly in  FIG. 6 , is caused to engage a corresponding interior surface of the flange  250  of the post  240  when the nut is rotated to limit travel of the nut  260 , which is freely rotatable. The nut  260  is attached for rotation about the first end  242  of the post  240  in which the first end is disposed within the center passageway  265  of the nut  260 , similar to the preceding prior art connector embodiment, although other forms of connectivity can be provided. 
     The connector body  220  receives the post  240  onto which the coupling nut  260  is threadingly secured and freely rotatable to enable attachment to an interface port (not shown). 
     In operation, a coaxial cable end  10  as prepared in accordance with  FIG. 1  is positioned within the second end  223  of the connector body  220  wherein the center conductor  18  and portions of the dielectric intermediate layer  16  are each disposed within the hollow confines of the post  240 . A compressive axial force is then applied to the second body section  225  of the connector body  220  using a compression tool (not shown) or otherwise in a direction toward the first end  222 . As this compressive axial force is applied, the weakened annular portion  226  is caused to fracture enabling the second body section  225  to break free from the first body section  224  and be shifted axially in the direction toward the first end  222  of the connector body  220  (i.e., toward the coupling nut  260 ), as shown in  FIG. 6 . The second body section  225  is therefore caused to move over the exterior surface of the cylindrical axial portion  234  as the distal diametrical portion  237  has an interior diameter which is larger than or equal to the exterior diameter of the cylindrical axial portion  234 . As this axial movement progresses in the direction  300 ,  FIG. 6 , the transitional portion  236 , including the ramped interior surface of the second body section  225 , is caused to directly impinge upon the exterior of the thin walled cylindrical axial portion  234 . Due to the relative size mismatch between the inner diameter of the proximal diametrical portion  235 , which is smaller than the external diameter of the cylindrical axial section  234 , that portion of the cylindrical axial portion  234  of the connector body  220  is caused to radially deform inwardly and therefore engage upon the shielding layer  14  and outer sleeve  12  of the prepared coaxial cable end  10   FIG. 6 , effectively retaining same within the connector  200 . The second body section  225  is therefore also effectively retained onto the exterior of the cylindrical axial section  234  of the connector body  220 . 
     The mode of operation with regard to the movement of the fractured second body section  225  is therefore nearly identical to that of prior art compression type coaxial cable connectors, such as those described in  FIGS. 1 and 2 . However and according to this design, a separate component is not required in the overall connector assembly. The center conductor  18  is then caused to extend through the post  240  and outwardly from the coupling nut  260  in a manner commonly known. The coupling nut  260  can be used in relation to an appliance port (not shown) to threadingly engage the port to the connector  200 . 
     PARTS LIST FOR FIGS.  1 - 6   
     
         
           10  cable end, coaxial 
           12  outer sleeve or jacket 
           14  shielding layer 
           16  dielectric layer, intermediate 
           18  center conductor 
           20  interface port 
           23  threads 
           30  threaded nut 
           31  first end 
           32  second end 
           33  threads 
           34  internal lip 
           40  post 
           41  first end 
           42  second end 
           43  hollow shaft portion 
           44  flange 
           45  annular shoulder 
           47  surface feature 
           50  connector body 
           51  first end 
           52  second end 
           53  deformable outer portion 
           55  outer surface, compliant 
           57  post mounting portion 
           58  outer annular recess 
           60  compression sleeve or member 
           61  first end 
           62  second end 
           65  center passageway 
           66  transitional section 
           67  first diametrical section 
           68  second diametrical section 
           80  connector body sealing member 
           100  connector, coaxial cable 
           200  connector, coaxial cable 
           220  connector body 
           222  first end 
           223  second end 
           224  first body section 
           225  second body section 
           226  weakened annular portion 
           227  proximal end, first body section 
           228  post retaining portion 
           229  distal end, second body section 
           230  center aperture 
           231  necked portion 
           232  annular flange 
           233  center passageway 
           234  cylindrical axial portion 
           235  proximal diametrical portion 
           236  transitional portion 
           237  distal diametrical portion 
           240  hollow post 
           242  first end 
           246  second end 
           248  surface feature 
           249  center aperture 
           250  flange 
           251  radial end edge 
           253  shaft portion 
           260  coupling nut 
           262  first end 
           264  second end 
           265  internal passageway 
           266  internal threads 
           300  direction 
       
    
     It will be readily apparent that other variations and modifications are possible within the intended ambits of this application and as defined by the following claims.