Abstract:
A cable attachment has a body and a plunger. During installation, a filling material binds the cable to the attachment.

Description:
PRIORITY CLAIM 
     This application claims the benefit of U.S. Provisional Patent Application No. 61/297,803 filed Jan. 24, 2010 and entitled CABLE ATTACHMENT WITH FILLING MATERIAL. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to cable attachments. In particular, a component such as a connector is attached to a cable using a filling material that tends to prevent relative motion between the cable and a connector part. 
     2. Discussion of the Related Art 
     Cable attachments typically rely on deformation of some part of the attachment to fix the attachment to the cable. Solutions that avoid attachment deformation are rare despite applications that would benefit from non-deforming attachments. 
     SUMMARY OF THE INVENTION 
     A cable attachment utilizes a filling material to resist relative motion between the cable and the attachment. In an embodiment: a body has a reservoir at least partially surrounding a central cavity of the body and a plunger has a central cavity with an end portion of the plunger inserted in the reservoir; a cable is inserted in the body central cavity and the plunger central cavity such that an annular space is formed between the cable and at least one of the body and plunger central cavities; fluid communication between the reservoir and the annular space is enabled by a radial port in a sidewall of the reservoir and transport of a filling material from the reservoir to the annular space is caused by a movement of the plunger relative to the body; resistance to relative motion between the cable at least one of the body; and, the plunger is improved by the transport of the filling material. 
     In an embodiment, a cable attachment comprises: a body having a reservoir at least partially surrounding a central cavity of the body; a plunger having a central cavity, an end portion of the plunger inserted in the reservoir; a fluid in the reservoir, a quantity of the fluid capable of being expressed from the reservoir by operation of the plunger; the central cavities of the body and the plunger operable to receive an electrical cable; and, the fluid operable to limit relative motion between an electrical cable and at least one of the body and the plunger. Some of these embodiments include one or more of: a hollow post adapted for insertion in an end of a coaxial cable; the hollow post extending between a fastener and the body; a coaxial cable inserted in the central cavities of the body and the plunger; the body and the coaxial cable wetted by fluid expressed from the reservoir; the fluid operable to limit relative motion between the coaxial cable and the body; wherein operation of the plunger forms a fixed seal between the plunger and an outer jacket of the coaxial cable; wherein a fluid residue limits the relative motion between the coaxial cable and the body; a wall between the post and the reservoir; at least one port in the wall capable of passing the fluid in response to operation of the plunger; the fluid is a component of a single or multi-component adhesive; a mixing part for mixing with the fluid; the plunger operable to mix the mixing part and the fluid; a movable seal covering the at least one port; the seal capable of passing the fluid in response to operation of the plunger; the mixing part is air; and, the mixing part is a component of an epoxy adhesive. 
     In an embodiment a method of attaching a connector to a coaxial cable comprises the steps of: providing a connector body having an annular reservoir surrounding a central cavity; providing a connector plunger having a central cavity; supplying the reservoir with a fluid useful in an adhesive filling; sealing one end of the reservoir with one end of a plunger; inserting a coaxial cable in the central cavities of the body and the plunger; operating the plunger to express the fluid into a space separating the coaxial cable and at least one of the body and the plunger; and transforming a quantity of the fluid into a solid adhering to the coaxial cable and at least one of the body and the plunger. Some of these embodiments include one or more of step of coupling a fastener to the body via a hollow post; step of forming a seal between the plunger and an outer jacket of the coaxial cable when the plunger is operated; the step of locating a wall between the post and the reservoir; step of forming at least one port in the wall capable of passing the fluid in response to operation of the plunger; steps of providing a mixing part, when the plunger is operated, mixing the mixing part with the fluid to transform the fluid into the solid adhesive; steps of providing a port seal in the form of an elastomeric band, the port seal encircling the wall and covering the at least one port and, operating the seal to uncover the port when the plunger is operated; wherein the mixing part is air; and, wherein the mixing part is a component of an epoxy adhesive. 
     In an embodiment a cable attachment comprises: a fastener, a hollow post, and a body mechanically coupled together; the hollow post adapted for insertion in the end of a coaxial cable; the body having a reservoir at least partially surrounding a central cavity of the body; a plunger having a central cavity, an end portion of the plunger inserted in the reservoir; a fluid in the reservoir, a quantity of the fluid capable of being expressed from the reservoir by operation of the plunger; a coaxial cable inserted in the central cavities of the body and the plunger; and, the fluid operable to limit relative motion between the cable and at least one of the body and the plunger. 
     In an embodiment a cable attachment comprises: a body having a reservoir at least partially surrounding a central cavity of the body; a plunger having a central cavity, an end of the plunger inserted in the reservoir; a coaxial cable inserted in the central cavities of the body and the plunger; an annular space extending between the cable and a wall bounding the body central cavity; fluid communication between the reservoir and the annular space enabled by a port in a sidewall of the reservoir; movement of the plunger operable to transport a filling material from the reservoir to the annular space via the port; and relative motion between the cable and the body being resisted by the transported filling material. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention is described with reference to the accompanying figures. These figures, incorporated herein and forming part of the specification, illustrate embodiments of the invention and, together with the description, further serve to explain its principles enabling a person skilled in the relevant art to make and use the invention. 
         FIG. 1A  shows a first cable attachment in accordance with the present invention. 
         FIG. 1B  shows the cable attachment of  FIG. 1  with a cable inserted. 
         FIG. 2  shows an end view of the cable attachment of  FIG. 1B . 
         FIG. 3  shows a coaxial cable attachment in accordance with the present invention. 
         FIG. 4  shows an end view of the cable attachment of  FIG. 3 . 
         FIG. 5  shows an exploded diagram of parts of the cable attachment of  FIG. 3 . 
         FIG. 6  shows the cable attachment of  FIG. 3  with filling material. 
         FIG. 7  shows the cable attachment of  FIG. 6  with a cable inserted. 
         FIG. 8  shows the cable attachment of  FIG. 7  after the plunger has been moved. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The disclosure provided in the following pages describes examples of some embodiments of the invention. The designs, figures, and description are non-limiting examples of embodiments of the invention for teaching persons of ordinary skill in the art how to make and use the invention. For example, other embodiments of the disclosed systems and methods may or may not include the features described herein. Moreover, disclosed features, advantages, and benefits may apply to only certain embodiments of the invention and should not be used to limit the disclosed inventions. 
       FIG. 1A  shows a cable attachment for use with filling material in accordance with the present invention  100 A. Attachment parts include a body  106  and a plunger  104  arranged symmetrically about a central axis  101 . The body has walls such as inner  122  and outer  120  walls bounding a reservoir such as an annular reservoir  107  and the reservoir surrounds all or a part of a body central cavity  111 . The plunger  104  has a plunger central cavity  113  and an end face  109  shaped for insertion into an open end  119  of the reservoir. Opposite the open end of the reservoir is a closed reservoir end  121 . 
     In an embodiment, the cable attachment  100 A is made from one or more of metals and non-metals such as polymers known to persons of ordinary skill in the art to be suited for this use. Exemplary metals include brass, copper, steel, stainless steel, titanium, alloys of these metals, and other metals and their alloys known by persons of ordinary skill in the art to be suited to this use. In an embodiment the cable attachment is made from one or more metals such as brass. In another embodiment, the cable attachment is made from one or more polymers such as plastics. Exemplary plastics include polyoxymethylene (“POM”), polyvinyl chloride (“PVC”), high density polyethylene (“HDPE”), Polyphenylene Sulfide (“PPS”), liquid crystal polymer (“LCP”), polyester, thermoset materials (phenolics and epoxies) and other plastics known to persons of ordinary skill in the art to be suited to this use. In an embodiment, the plunger  104  is made from a metal such as brass and the body is made from a plastic such as polyoxymethylene (“POM”). 
       FIG. 1B  shows a cable inserted in the cable attachment  100 B. In particular, a cable is inserted in the central cavities  111 ,  113  of the attachment body  106  and plunger  104 .  FIG. 2  shows an end view of the attachment and inserted cable  200 . 
     A first filling material  114  is located in the reservoir  107  such that as the plunger is moved toward the closed end of the reservoir  121 , an end face such as an annular end face of the plunger  109  causes the first filling material to flow  117  through one or more ports  118  in the inner wall of the body  122 . 
     The plunger&#39;s end face  109  is opposite a cable entry end of the plunger  127 . When a cable is located within the central cavities of the body and plunger  111 ,  113 , annular spaces  123 ,  130  are formed between the cable exterior  103  and each of the inner body wall  122  and a plunger inner surface  125 . At least a portion of the annular space between the cable exterior and the body inner wall is an annular fill space  123 . 
     Moving the plunger toward the reservoir closure  121  causes the first filling material  114  to flow through the body inner wall ports  118  and to enter the annular fill space  123 . In some embodiments, only a first filling material is used. In other embodiments a second filling material  116  is also used. For example, the second filling material can be located in the fill space before the second filling material enters the fill space (as shown). 
     In other embodiments, both the first and second filling materials  114 ,  116  flow through the ports  118  by action of the plunger  104 . In some embodiments, a valve(s) such as a rubber ring or flap is associated with one or more ports  118  and movement of the plunger  104  opens the valve(s). (See infra.) This arrangement provides one solution for isolating the first fill material  114  from air, as with an air actuated filling material. 
     Filling material  114 ,  116  in the annular fill space  123  is contained by sealing structure(s), viscosity, or other means known to persons of ordinary skill in the art. In some embodiments, sealing structures are adjacent to and/or abutting the cable. In various embodiments, one or more sealing structures are used such as a first seal  132  located between the cable  102  and the inner wall of the body  122  near the body closure  121 , a second seal  134  located between the cable and the inner wall of the body  122  near the open end of the reservoir  119 , and a third seal  136  located between the cable and the inner wall of the plunger  125  near the cable entry end of the plunger  127 . 
     It is not necessary for filling materials to completely fill the fill space  123 . For example, to the extent the filling material(s)  114 ,  116  expand and press against the cable exterior  103  and the body  106 , relative motion between the cable  102  and the body or attachment  100 B is limited. And, for example, to the extent the filling materials(s) adhere to the cable exterior and the body or attachment, relative motion between the cable and the body is limited. 
     Filling materials include materials known to persons of ordinary skill in the art as being suitable for restraining, adhering, and/or binding the cable  102  to the body  106  and/or to the attachment  100 A-B. Exemplary filling materials include adhesives such as single and multiple component adhesives and volume expanding fillers. 
     In particular, filling materials include single and multipart adhesives. Single part adhesives include cyanoacrylate type adhesives such as Krazy Glue®. Two part adhesives include two-part epoxy adhesives such as 3M® Scotch Weld® adhesives including electrical grade adhesives and 3M&#39;s quick setting DP100 and DP105 adhesives. Yet another two-part epoxy adhesive is sold by ND Industries, Inc., Troy Mich., under the brand name ND Microspheres® 294, a micro-encapsulated epoxy product. 
     Filling materials also encompass volume expanding fillers such as single and multipart fillers including expanding foams. Suitable expanding foams include polyisocyanurate and polyurethane two-component expanding sealants from Fomo Products, Inc. of Norton, Ohio sold under the Silent Seal® brand. Yet another two-component expanding polyurethane foam sealant is available from American Industrial Supply Inc. of Burbank, Calif. under the brand AMERFOAM. 
       FIG. 3  shows a coaxial cable attachment for use with filling material in accordance with the present invention  300 .  FIG. 4  shows an end view of the coaxial cable attachment  400 . A fastener  352  rotatably engages a flange  354  of a hollow post  355 . Adjacent to the fastener and engaging the post is a body  306  having an inner wall  322  spaced apart from the post and forming an annular space  366 . In an embodiment, the fastener has internal threads  353  for connection to a threaded port such as the port of a radio frequency device. 
       FIG. 5  shows an exploded diagram of attachment parts  500  used in the coaxial cable attachment of  FIG. 3 . The post  355  rotatably couples the fastener  352  to the body  306 . In some embodiments, a seal such as an elastomeric O-ring  370  spaces a flange of the post  354  away from an inner shoulder of the fastener  357 . One or more ports  318  are located in an inner wall of the body  322  and in some embodiments, an elastomeric ring  360  presses against the ports to form a valve at each port. As shown, the sleeve  362  is fitted over an outer shoulder  372  of the body  306  to form the outer wall of the body  320 . An annular opening  319  between the inner and outer walls of the body provides a space for insertion of an end  309  of a plunger  304 . A removable elastomeric band  376  provides a means for marking the attachment when it is fitted to an outer recess  374  of the plunger. 
     In various embodiments, the cable attachment parts  300 ,  500  are made from one or more of metals and polymers such as the exemplary metals and non-metals discussed above and metals and polymers known by persons of ordinary skill in the art to be suited to this use. In an embodiment, the cable attachment is made from a metal such as one or more of the exemplary metals listed above, for example, brass. In another embodiment, the cable attachment is made from one or more of the exemplary polymers and plastics listed above, for example, POM. And, in some embodiments, the cable attachment parts are made from both metals and plastics. In an embodiment, the plunger  304 , sleeve  362 , fastener  352 , and post  355  are made from a metal such as brass and the body  306  is made from a plastic such as polyoxymethylene (“POM”). 
     The body  306  and the plunger  304  are symmetrically arranged about a central axis  301 . The outer sleeve  362  is integral with or mates with (as shown) the body and provides an outer body wall  320  spaced apart from the inner body wall  322 . The inner and outer body walls bound a reservoir such as an annular reservoir  307  and the reservoir surrounds all of or a portion of a space such as an annular space  366  about the post  355 . 
     The plunger  304  has a plunger central cavity  313  and a first end  309 , opposite a second end  327 , is shaped for insertion into an open end  319  of the body reservoir  307 . Opposite the open end of the reservoir is a closed reservoir end  321 . 
       FIG. 6  shows the plunger partially inserted in the reservoir  600  (see also  FIGS. 3 ,  5 ). A first filling material  314  is located in the reservoir  307  such that as the plunger  304  is moved toward the closed end of the reservoir  321 , an end face such as an annular end face of the plunger  309  will urge the first filling material to flow through one or more ports  318  in the inner wall of the body  322 . 
       FIG. 7  shows a coaxial cable located in an attachment  700  (see also  FIGS. 3 ,  5 ,  6 ). When the cable is inserted in the attachment, the barbed end of the hollow post  358  (see  FIG. 6 ) is inserted in the end of the cable  408  such that the post surrounds a portion of the coaxial cable including the cable central conductor  402  and its insulating/dielectric layer (not shown). Another portion of the coaxial cable including a grounding sheath  404  and a cable outer protective jacket  303  surrounds the post. Insertion of the coaxial cable creates a fill space such as an annular fill space  323  including at least a portion of the space between the cable exterior  303  and the inner wall of the body  306 . 
     As can be seen in this embodiment, preparation of the cable end  408  is such that the cable central conductor  402  will extend through the fastener and the exposed grounding sheath  404  will occupy a portion of the annular fill space  323 . 
       FIG. 8  shows the attachment after movement of fill material  800  (see also  FIGS. 3 ,  5 - 7 ). In particular, moving the plunger toward the reservoir&#39;s closed end  321  forces the first filling material  314  through the body inner wall ports  318  and into the annular fill space  323 . 
     In some embodiments, only a first filling material  314  is used. In other embodiments a second filling material  316  is also used. Here, the fill material shown  406  includes, depending on the embodiment, one or both of the first and second filling materials. 
     In some embodiments, the second filling material  316  can be located in the annular fill space  323  before the second filling material enters the fill space (as shown). In other embodiments, both the first and second filling materials are pushed through the ports  118  by action of the plunger  304 . And, in some embodiments, a valve(s) such as a rubber ring or flap  360  is associated with one or more ports  118  and movement of the plunger  104  opens the valve(s). The valve provides a useful feature in some embodiments for limiting exposure of filler material to air and/or for separating one filler material from another. 
     In various embodiments, filling material  314 ,  316  is contained by sealing structures adjacent to and/or abutting the cable. In an embodiment, the boundaries of the annular fill space  323  include the cable exterior  303 , the body inner wall  322 , a portion of a plunger wall  412 , a plunger sealing structure  336  and a body sealing structure  332 . In various embodiments, one or more sealing structures are used such as any of those described above. 
     It is not necessary for filling material(s)  314 ,  316  to completely fill the fill space  323 . To the extent the filling material(s) expand and press against the cable exterior  303  and the body  306 , relative motion between the cable  102  and the body is limited. And, to the extent the filling materials(s) adhere to the cable exterior and the body, relative motion between the cable and the body is limited. In an embodiment, the filling material(s) provide a barrier against cable  302  and or connector  800  degradation including degradation due to environmental factors such as moisture. 
     Filling materials include materials known to persons of ordinary skill in the art as being suitable for adhering and/or binding the cable  302  to the body  106  and or to the attachment  300 ,  600 ,  700 ,  800 . Filling materials include adhesives and volume expanding fillers. 
     In particular, filling materials include single and multipart adhesives. Single part adhesives include cyanoacrylate type adhesives such as Krazy Glue®. Two part adhesives include two-part epoxy adhesives such as 3M® Scotch Weld® adhesives including electrical grade adhesives and 3M&#39;s quick setting DP100 and DP105 adhesives. Yet another two-part epoxy adhesive is sold by ND Industries, Inc., Troy Mich., under the brand name ND Microspheres® 294, a micro-encapsulated epoxy product. 
     Filling materials also include volume expanding fillers including single and multipart fillers such as expanding foams including polyisocyanurate and polyurethane two-component expanding sealants from Fomo Products, Inc. of Norton, Ohio sold under the Silent Seal® brand. Yet another two-component expanding polyurethane foam sealant is available from American Industrial Supply Inc. of Burbank, Calif. under the brand AMERFOAM. 
     While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. It will be apparent to those skilled in the art that various changes in the form and details can be made without departing from the spirit and scope of the invention. As such, the breadth and scope of the present invention should not be limited by the above-described exemplary embodiments, but should be defined only in accordance with the following claims and equivalents thereof.