Abstract:
An in-line connector for coaxial cable connectors, which enables two flush cut cables of two different diameters to be spliced together without further cutting of the cable&#39;s insulator or outer conductor jacket. A longitudinal connector has an internal concentrically mounted conductor member which contacts the inner wire conductor of each cable to be spliced. A pair of metallic sleeves extend from the conductor and are inserted into each cable to make contact with the woven metallic sheath of each cable. Each of said sleeves comprises two sections having two different internal diameters to accommodate differently sized cables. A collapsible sleeve is concentrically mounted to each end of the connector and engages the connector to inhibit relative rotation. A lock nut threadably engages each of the collapsible sleeves to cover the connection and secure each cable to the connector.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a coaxial cable connector and more particularly to an in-line coaxial cable connector capable of connecting together two flush cut cables of two different diameters, suitable for use in radio and video signal transmission. 
     2. Description of the Prior Art 
     Currently there are numerous connectors which enable two coaxial cables to be spliced together. However, these connectors require the cable to be cut such that the insulating cover is cut back to expose the woven metallic sheath. Additionally, the cable must be cut such that the internal wire conductor extends beyond the remaining portion of the cable to contact a female receptive portion of the cable. This cutting requires the skill of an experienced cable layer and often a cut is made too deep or all the way through the cable. Such an improper cut will require an additional cut thus shortening the length of the cable and wasting the portion which was improperly severed. This type of cutting takes an additional amount of time when attempting to splice together two coaxial cables. 
     For example U.S. Pat. No. 5,217,392 discloses a coaxial cable splice connector comprising outer conductor shells to make contact with the woven metallic sheath of each cable and an inner conductor bore to make contact with the central wire conductor of each cable. However, the cables to be spliced in U.S. &#39;392 must first be cut to peel back the outer insulator member and expose the woven metallic sheath. Additionally, the cable must be cut such that the inner wire conductors extends past the remaining portion of the cable to engage the inner conductor bore. 
     There is a need to enable two coaxial cables to be spliced together in-line which requires ease of assembly and simple cut of the cables to be spliced without any reduction in the quality of radio or video reception. 
     Furthermore, there are various types of radio and video cables on the market having different diameters. Specifically, different makes of coaxial cable have an inner dielectric of varying diameters. Different coaxial cable connectors are needed in order to splice together cables having different diameters. Therefore, there is a need for the coaxial cable connector to accommodate cables of different diameter dielectric material. 
     The present invention attempts to remedy the drawbacks of the prior art and provide a simpler, less expensive device which is easier to assemble, enables to accommodate cables of different diameters and maintains the quality of radio and video reception. 
     SUMMARY OF THE INVENTION 
     It is therefore, the principal object of the present invention to provide an improved in-line cable connection suitable for use with a radio or video receptive antenna. 
     It is also an object of the present invention to allow the simple connection of two coaxial cables that have been simply transversely cut straight through wherein the end of the cable remains flush. 
     It is also an object of the invention to provide a means to secure a cable to the connector wherein a collapsible sleeve is mounted about the connector and a projection engages the connector to prevent relative rotation. 
     It is also an object of the invention to provide a coaxial in-line connector which requires no specialized tool other than a simple cutting tool to cut the ends of the cables in order to splice the cables together. 
     Further object of this invention is to provide a coaxial in-line connector which enables the simple connection of coaxial cables of two different diameters. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a longitudinal sectional view of the in-line connector connecting two coaxial cables. 
     FIG. 2 is an exploded longitudinal sectional view of the in-line connector. 
     FIG. 3 is a longitudinal sectional view of the interface connector. 
     FIG. 4 is a transverse sectional view of the interface connector taken along line  4 — 4  of FIG.  3 . 
     FIG. 5 is an end view of the collapsible sleeve taken along line  5 — 5  of FIG.  6 . 
     FIG. 6 is a longitudinal sectional view of the collapsible sleeve. 
     FIG. 7 is an end view of the collapsible sleeve taken along line  7 — 7  of FIG.  6 . 
     FIG. 8 is an exploded longitudinal sectional view of the preferred embodiment of the in-line connector. 
     FIG. 9 is a transverse sectional view of the interface connector taken along line  9 — 9  of FIG.  8 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIGS.  1 - 7  in detail, one embodiment of the cable joint of the present invention is depicted in FIG. 1, showing the joining of two coaxial cables  9 . A pair of cables  9  each have an inner conductor  10  concentrically embedded within a dielectric material  12  which is in turn concentrically surrounded by a woven metallic sheath  11  which is in turn is concentrically surrounded by an insulating material  13 . The ends of the cables are generally flush cut to define a generally flat transverse area as shown in FIG. 1 at  14 . The flush cut end of each cable lies adjacent to an exposed portion of the connector  1  and insulator  2 . 
     Now referring to FIG. 2, an interface connector  1  has a centrally located nut portion  5  which has an annular inward extending portion  5   a , the axis of which defines a common longitudinal axis. Within the annular inward extending portion  5   a  of the nut portion  5  are coaxially disposed an insulator  2  and a conductor  3 . The width of the insulator  2  is substantially equal to the width of the annular inward extending portion  5   a  so as to provide a generally planer or flat exposed surface. The conductor member  3  is of such a width that when centrally disposed within insulator  2  it extends beyond the insulator on both sides. This extended portion of the conductor member  3  provides an exposed surface to contact the inner conductor member  10  of the cables  9  which are to be spliced together. The length that the conductor  3  extends from the insulator is such as to afford a good contact with the inner conductor  10  of the cable  9  while allowing the transverse surface area of the cable to rest next to the generally planar surface defined by the insulator  2  and inwardly extending portion of the central nut portion  5 . 
     From the central nut portion  5  extends a pair of metallic sleeves  4   a  and  4   b . Sleeves  4   a ,  4   b  are coaxially aligned with the common axis, defined by the axis of the annular extending portion  5   a , and extend in opposite directions from the central nut portion  5 . The diameter of each of the metallic sleeves  4   a  and  4   b  is substantially the same as the diameter of woven metallic sheath  11  of the coaxial cables  9  so as to make good contact therebetween. The diameter of the metallic sleeves  4   a  and  4   b  can hence be either slightly larger or slightly smaller than the woven metallic sheath  11 . 
     In order to splice two coaxial cables together each cable  9  is completely severed in a direction transverse to its axis to expose a flush end surface. The cable  9  and the interface connector  1  are coaxially aligned and then simply pushed toward one another such that one side of the interface connector is inserted into one of the cables. The cable  9  and connector  1  are displaced toward one another such that the exposed flush surface of the cable rests against or near the generally planar surface defined by the insulator and inward extending portion of central nut  5  as shown at  14 . The connector conductor  3  extends into the dielectric material  12  to make contact with the inner conductor  10  of cable  9 . The metallic sleeves  4   a  and  4   b  extend into the cable  9  and surround the dielectric material and make contact with the metallic sheath  11  of the cable  9 . The diameter of the metallic sleeve is such that it either makes contact with the inner peripheral surface or the outer peripheral surface of the metallic sheath  11  while being disposed within the cable insulator  13 . The connection between each of the inner conductors  10  of each cable  9  is made through the conductor member  3  of the interface conductor  1 . The connection between the woven metallic sheath  11  of each cable  9  is made through the two metallic sleeves  4   a  and  4   b  and the central nut portion  5  of the interface connector  1 . The central nut portion  5  and the metallic sleeves  4   a  and  4   b  are integrally formed of a material such as copper, or the like, to afford a good connection. The connection is thus established between each coaxial cable. 
     In order to secure the connection of each cable  9  to the interface cable  1 , a collapsible sleeve  7  and a locknut  8  are provided. At one end of the collapsible sleeve  7  a portion is threaded on its outer peripheral surface  7   a . Longitudinal slits  7   b  are cut along this threaded portion  7   a  of sleeve  7  so that the threaded portion  7   a  can expand and contract to accommodate cables of varying diameter. At the other end of sleeve  7  extend a plurality of projections  7   c  which extend in the longitudinal direction. Central nut portion  5  of the interface connector has a plurality of longitudinal notches  6  extending along its entire width parallel to the commonly defined axis. These notches  6  correspond to each of the projecting portions  7   c  of the collapsible sleeve  7 . Each projection portion  7   c  is inserted into a corresponding notch  6  in order to prevent relative rotation between the interface connector  1  and the collapsible sleeve  7 . A lock nut  8  having a threaded internal surface  8   a  threadingly engages the external surface  7   a  of the collapsible sleeve  7  such that as the lock nut  8  is tightened the diameter of the threaded portion of the collapsible sleeve  7   a  is decreased. 
     The assembly and securement of the connection will now be described. Once each cable  9  has been flush cut, the locknut  8  and then the collapsible sleeve  7  are slid over each cable  9 . The collapsible sleeve  7  is disposed over the cable, and consequently over the insulator portion  13  thereof, such that the projecting portions  7   c  extend toward the flush cut end of the cable  9 . One end of the interface connector  1  is coaxially aligned with one of the cables  9  and the two are simply urged toward one another such that one end of the interface connector  1  is inserted into the cable  9 . The collapsible sleeve  7  is slid up towards the interface connector  1  until the projecting portions  7   c  of the collapsible sleeve extend into a corresponding notch  6  of the central nut portion to prevent relative rotation therebetween. The lock nut  8  is then slid up to and threadably engages the collapsible sleeve  7 . The locknut  8  is tightened so as to reduce the diameter of the collapsible sleeve  7  to crimp the insulator portion  13  of cable  9  against one of the metallic sleeves  4   a  or  4   b . This crimping action affords a tight friction connection and prevents the cable  9  from dislodging from the interface connector  1 . This crimping action additionally, urges the woven the metallic sheath  11  of cable  9  against the external surface of the metallic sleeves  4   a  and  4   b  to afford a better connection therebetween. Once one cable  9  is secured, the same process is repeated for the other cable to the other side of the interface connector  1 ; a stable in-line electrical connection between each cable has thus been established. 
     In an alternate method of assembly two longitudinal cuts may be made into the insulator portion  13  to ease the insertion of the metallic sleeves  4   a  and  4   b  within the insulator portion  13  and over the dielectric material  12 . These two cuts preferably are spaced 180° apart so as to be opposite one another. The length of these cuts would be sufficient to allow the insulator portion to expand slightly to ease the insertion of the metallic sleeve over the dielectric material  12  and within the insulator portion  13 . Additionally, the length of the cuts should not exceed the width of the sleeve  7  so as to ensure that neither the metallic sheath  11  nor the metallic sleeve is exposed to the environment after complete assembly of the connector. When cutting the insulator portion longitudinally, the depth of the cut should not exceed the thickness of the insulator portion in order to preserve the integrity of the woven metallic sheath  11  and dielectric material  12 . 
     Referring now to FIG. 8 that illustrates the preferred embodiment of the present invention, an interface connector  20  has a centrally located nut portion  25  which has an annular inward extending portion  25   a , the axis of which defines a common longitudinal axis. An insulator  22  and a conductor  23  are coaxially disposed within the annular inward extending portion  25   a  of the nut portion  25 . The width of the insulator  22  is substantially equal to the width of the annular inward extending portion  25   a  so as to provide a generally planer or flat exposed surface. The conductor member  23  is of such a width that when centrally disposed within insulator  22  it extends beyond the insulator on both sides. This extended portion of the conductor member  23  provides an exposed surface to contact the inner conductor member  10  of the cables  9  which are to be spliced together. The length that the conductor  23  extends from the insulator is such as to afford a good contact with the inner conductor  10  of the cable  9  while allowing the transverse surface area of the cable to rest next to the generally planar surface defined by the insulator  22  and inwardly extending portion of the central nut portion  25 . 
     From the central nut portion  25  extends a pair of metallic sleeves  24   a  and  24   b . Sleeves  24   a ,  24   b  are coaxially aligned with the common axis, defined by the axis of the annular extending portion  25   a , and extend in opposite directions from the central nut portion  25 . The exterior diameter of the metallic sleeves  24   a  and  24   b  can be either slightly larger or slightly smaller than the diameter of the woven metallic sheath  11 . Each of said sleeves  24   a ,  24   b  comprises two sections having different interior diameters in order to accommodate two different types of coaxial cables having dielectric material  12  of different diameters: a first section  24   a ′,  24   b ′ adjacent to the central nut portion  25 , and a second section  24   a ″,  24   b ″ adjacent to the first sections  24   a ′ and  24   b ′. An interior diameter of the first section  24   a ′,  24   b ′ is smaller than an interior diameter of said second section  24   a ″,  24   b ″ so that the first section  24   a ′,  24   b ′ accommodates large diameter cables, while the second section  24   a ″,  24   b ″ accommodates smaller diameter cables. A ramp section  24   a ′″,  24   b ′″ of varying internal diameter is located between the first section  24   a ′,  24   b ′ and the second section  24   a ″,  24   b ″, providing smooth transition between those first and second sections. In order to secure the connection of each cable  9  to the interface cable  20 , a collapsible sleeve  27  and locknut  28  are provided. At one end of the collapsible sleeve  27  a portion is threaded on its substantially cylindrical outer peripheral surface  27   a  and an exterior end portion  27   d  of the collapsible sleeve  27  is tapered. Longitudinal slits  27   b  are cut along the threaded portion  27   a  and the tapered portion  27   d  of the sleeve  27  so that the portion of the sleeve  27  can expand and contract to accommodate cables of varying diameter. At the other end of sleeve  27  a plurality of projections  27   c  are provided which extend in the longitudinal direction. The central nut portion  25  of the interface connector has a plurality of longitudinal notches  26  extending along its entire width parallel to the commonly defined axis. These notches  26  correspond to each of the projecting portions  27   c  of the collapsible sleeve  27 . Each projection portion  27   c  is inserted into a corresponding notch  26  in order to prevent relative rotation between the interface connector  20  and the collapsible sleeve  27 . A locknut  28  has a threaded internal surface  28   a  at one end of the locknut  28  and an internal inwardly tapered surface  28   b  at the other end. The interior diameter of the internal inwardly tapered surface  28   b  progressively decreases toward said other end of the locknut  28 . The threaded internal surface  28   a  of the locknut  28  threadingly engages the external threaded surface  27   a  of the collapsible sleeve  27  such that as the locknut  28  is tightened, the internal tapered surface  28   b  of the locknut  28  engages exterior tapered portion  27   d  of the collapsible sleeve  27  and the diameter of the threaded portion of the collapsible sleeve  27   a  is decreased positively clamping the insulator portion  13  of the cable  9  against the external surface of the sleeves  24   a  and  24   b.    
     The assembly and securement of the connection in accordance with the preferred embodiment of the invention will now be described. Once each cable  9  has been flush cut, the locknut  28  and then the collapsible sleeve  27  are slid over each cable  9 . The collapsible sleeve  27  is disposed over the cable, and consequently over the insulator portion  13  thereof, such that the projecting portions  27   c  extend toward the flush cut end of the cable  9 . One end of the interface connector  20  is coaxially aligned with one of the cables  9  and the two are simply urged toward one another such that one end of the interface connector  20  is inserted into the cable  9 . If the cable of small diameter is employed, it engages the first sections  24   a ′,  24   b ′ of the metallic sleeves  24   a  and  24   b . However, when the cable of large diameter is employed, it engages the second sections  24   a ″,  24   b ″ of the metallic sleeves  24   a  and  24   b . Then the collapsible sleeve  27  is slid up towards the interface connector  20  until the projecting portions  27   c  of the collapsible sleeve extend into a corresponding notch  26  of the central nut portion to prevent relative rotation therebetween. The lock nut  28  is then slid up to and threadably engages the collapsible sleeve  27 . The locknut  28  is tightened so as to engage its internal tapered surface  28   b  with the external tapered portion  27   d  of the collapsible sleeve  27  and reduce the diameter of the collapsible sleeve  27  to crimp the insulator portion  13  of cable  9  against one of the metallic sleeves  24   a  or  24   b . This crimping action affords a tight friction connection and prevents the cable  9  from dislodging from the interface connector  20 . This crimping action additionally, urges the woven the metallic sheath  11  of cable  9  against the external surface of the metallic sleeves  24   a  and  24   b  to afford a better connection therebetween. Once one cable  9  is secured, the same process is repeated for the other cable to the other side of the interface connector  20 ; a stable in-line electrical connection between each cable has thus been established. 
     The preferred method of assembly and securement of the cable connection in accordance with the alternative embodiment of the invention, is substantially identical to one that was described above in connection with the first embodiment of the present invention. 
     While the coaxial cable connector of this invention has been shown and described with reference to the particular embodiments, it will be understood to those possessing skill in the art that various changes to the form and detail may be made therein without departing from the spirit and scope of the invention.