Cable Connector Apparatus

Abstract

A cable connector apparatus for electrically connecting a coaxial cable to a fixed device such as a coupler or amplifier has a connector assembly adapted to be fixedly secured to a cable and a connector assembly adapted to be fixedly secured to the device. One of the connector assemblies is rotatably received within the other connector assembly. Respective pairs of contacts within each connector assembly are so disposed to transmit the electrical signal from the cable to the device despite relative rotation between the cable and the device. Mechanical means retain the connector assemblies in mechanical and electrical contact during relative rotation between the connector assemblies.

Description

This invention relates to a cable connector apparatus.

More particularly, the invention relates to a cable connector apparatus especially adapted for use in a cable antenna television (CATV) transmission system.

In a further and more specific respect, the invention concerns a cable connector apparatus for electrically and mechanically connecting a CATV cable to a stationary device such as a coupler or amplifier wherein the cable is permitted repeated cyclical rotational movement and vibration relative the device without impairment of the connection or damage to the cable.

In a cable antenna television (CATV) system, a central antenna is situated in a remote location selected for proper reception of line-of-sight television signals. The signals are then transmitted to the individual subscriber's television set by means of a coaxial cable and a series of active and passive devices. A primary cable extends from the central antenna to the area or neighborhood to be serviced, whereafter drop leads transmit the signals from the primary cable to the individual subscriber.

Since the primary coaxial cable generally traverses an extended distance and accommodates numerous drop leads, a series of active and passive devices are required. For example, the primary coaxial cable generally having a diameter of approximately three-fourths inch loses signal strength at approximately one decibel per hundred feet. It is necessary that an amplifier be incorporated into the cable system approximately every 2,200 feet within the area to be serviced. The primary cable is terminated with a passive device from which secondary cables are used to service smaller residential areas. Within the limited area, the secondary cable transmits signals to a plurality of directional devices from which drop leads transmit the signal to the individual subscriber's television set, e.g., the secondary cable may be supported in an alley between two rows of houses and at every other corner of a residential lot, a directional device may be employed to provide service to the four juxtaposed residential lots.

The primary and secondary coaxial cables extending between the central antenna and ultimate directional device are airborne cables supported by a plurality of spaced poles. Due to the necessary frequency of devices for both signal modification and junctional purposes, numerous connections are required in the installation of the cable system. Each active device requires two connections with the cable, one to receive the incoming signal from the previous section of cable and one to transmit the signal to the next sequential segment of cable. The directional devices, in addition to the above-noted connections, require several additional connections to transmit the signal to the individual drop leads. In accordance with conventional practice, as with other types of airborne cables, a certain amount of slack or sag is mintained in a coaxial cable from pole to pole or from connection to connection to limit the tension upon the cable.

Due primarily to intermittent wind movement, the cable is subjected to various forces, including alternate rotation and vibration. If the coaxial cable, generally a tubular foil sheath with an inner wire conductor, is securely fastened to the terminal, the almost continuous alternating rotation and vibration will eventually fatigue the cable, causing it to rupture. Since the cable is conventionally secured to the terminal junction box with a screw-type fitting, the above forces loosen the connection and repeated vibration or alternate rotation eventually causes the connection to disengage from the device. This results in an inconvenience to the subscribers and imposes undue maintenance requirements upon the CATV system owners.

Accordingly, it is an object of the present invention to provide an improved cable connector apparatus.

Another object of the invention is to provide an improved cable connector apparatus for use in a CATV cable transmission system for connecting the coaxial transmission cable to a stationary coupler or other device.

Yet still another object of the present invention is to provide a connector apparatus for electrically and mechanically connecting a coaxial cable to a fixed terminal wherein the mechanical and electrical connection therebetween is maintained despite relative movement caused by repeated cycles of rotational movement or undulations of the cable.

Yet still another object of the present invention is to provide a connector apparatus of the above type in which the mechanical and electrical connection between the coaxial cable and the device may be readily and easily accomplished in field installations.

Briefly, to accomplish the desired objectives of the present invention, the cable connector apparatus comprises a pair of connector assemblies. A first connector assembly is adapted to be fixedly secured to the coaxial cable and provided with a pair of electrical contacts, one of which is electrically connected to the outer tubular conductor and the other of which is electrically connected to the inner conductor wire. A second connector assembly, also provided with a pair of electrical contacts, is fixedly secured to the fixed device. The first and second connector assemblies are so constructed that one of the connector assemblies is rotatably received within the other connector assembly. When so received, each electrical contact within one of the connector assemblies effects electrical connection with a respective electrical contact within the other connector assembly. Each contact is annularly disposed whereby electrical contact is maintained during relative rotational movement between the two connector assemblies of the connector apparatus. Means are provided for detachably engaging the connector assemblies and maintaining the electrical and mechanical connection and providing for the relative rotational movement as described above.

Further objects and advantages of the present invention will become more clearly apparent to those skilled in the art from the following detailed description of a preferred embodiment of the present invention taken in conjuction with the drawings, in which:

FIG. 1 is a perspective view illustrating a typical fixed device having coaxial cables connected thereto with the connector apparatus of the present invention;

FIG. 2 is an exploded perspective view of one of the connector apparatuses of FIG. 1;

FIG. 3 is an exploded perspective view, partially in section, specifically illustrating the elemental components of a preferred connector assembly especially adapted to be fixedly secured to a coaxial cable;

FIG. 4 is an enlarged perspective view, partly in phantom outline, especially detailing the element as denoted by the bracket 4 within FIG. 3; and

FIG. 5 is an elevation view in section taken along the line 5--5 of FIG. 1.

Turning now to the drawings, in which the same reference character indicates corresponding elements throughout the various views, attention is first directed to FIG. 1 which shows a device 10 having a pair of coaxial cables 11 each connected thereto with a connector apparatus generally designated by the reference character 12 constructed in accordance with the teachings of the preferred embodiment of the present invention. While the device 10 herein shown does not represent any specific type of device used in CATV system, it is understood that the device generally represents any active or passive device which may be employed in the system. Although not specifically herein illustrated, it is understood that the under surface 13 of the device 10 may be adapted to receive a plurality of the connector apparatuses 12 to accommodate drop leads to individual subscribers' television sets.

FIG. 2 illustrates a preferred embodiment of the connector apparatus 12 of the present invention as it would appear as employed in field practice to connect the coaxial cable 11 to the device 10. The representative coaxial cable 11 has an elongate tubular outer conductor 14 generally fabricated from a metal foil and an inner conductor wire 17 coaxially located within the tubular outer conductor. A dielectric 18, such as a polystyrene foam, insulates the inner conductor wire 17 from the tubular outer conductor 14. In the instant illustration, the outer conductor 14 is exposed to the atmosphere; however, alternate coaxial cables of the type used for CATV transmission may employ an outer protective jacket such as might be fabricated from polyethylene. In preparing the cable 11 for use with the connector apparatus of the present invention, a portion of the outer jacket 14 and dielectric 18 is stripped away to expose a length of the inner conductor wire 17. If the cable is of the type employing an outer protective jacket, a portion of the protective jacket must also be stripped away to expose a given length of the outer conductor.

The connector apparatus 12 has a connector assembly 19 adapted to be firmly secured to the coaxial cable 11 and a connector assembly 20 adapted to be fixedly secured to the device 10, the operative elemental components of which will be discussed in detail hereinafter. The cable 11 prepared as above-described is inserted through the aperture 21 of the union nut 22, the O-ring seal 23 and the aperture 24 of the dust shield 27. Thereafter, the cable 11 is inserted through the aperture 28 of the connector assembly 19 and securely affixed thereto. The device 10 has an aperture 29 therein which supports a female screw flight which threadedly engages the male screw flight 30 of the connector assembly 20. The O-ring seal 31 provides a water and dirt-free union between the device 10 and the connector assembly 20.

After preliminary preparation as described above, the connector assembly 19 is inserted into the connector assembly 20. The dust shield 27 is urged forwardly along the coaxial cable 11 to encase the connector assembly 19 and abut the connector assembly 20 and the O-ring 23 is positioned against the dust shield 27. The connection is completed by urging the union nut 22 along the cable 11 encasing the dust shield 27, the connector assembly 19 and threadedly engaging the connector 20. As will become apparent hereinafter, the connector 19, fixedly secured to the coaxial cable 11, is rotatable within the connector assembly 20 and is held in mechanical and electrical connection by the union nut 22.

The connector assembly 19 is herein illustrated in detail in connection with FIGS. 3 and 4. First provided is a cylindrical outer conductor 32 having a reduced diameter forward section 33 and a female screw flight 34 within the rear portion. Longitudinal slits 37 divide the reduced diameter forward section 33 into a plurality of forwardly extending contact members. A collet 38 having a probe 39 extending forwardly therefrom is coaxially maintained within the outer conductor 32 by the insulator bushing 40 having an aperture 41 therein through which the probe 39 passes. An insulative outer covering 42, as shown in the phantom outline, encases the collet 38. The insulative outer covering 42 is provided with a flange 43 at the forward end which abuts the insulator bushing 40 and a conical rearward end 44 which cooperates with the collet closer 47 to fixedly retain the inner conductor wire 17 within the collet 38.

A cable nut 48 has a first axial bore 49 sized to receive the split sleeve 50 and a second axial bore 51 sized to receive the outer conductor 14 of the coaxial cable 11. The sleeve 50 has identically beveled edges 52 which mate with the beveled rearward end 53 of the axial bore 49 and the beveled face 54 of the ferrule 55. As will be understood by those skilled in the art, after the coaxial cable 11 has been inserted through the aperture 51 such that the inner conductor 17 extends into the collet 38 and the outer conductor 14 extends through the sleeve 50 threadedly engaging the male screw flight 56 of the union nut 48 and the female screw flight 34 of the outer conductor 32, subsequent rotation between the outer conductor and the cable nut compresses the sleeve 50 and the collet 38 to fixedly secure the outer conductor 14 and the inner conductor 17, respectively, for both mechanical and electrical connection.

Attention is now directed to FIG. 5 which shows the interaction of the operative elements of the connector assembly 19 securely affixed to the coaxial cable 11 and engaged within the connector assembly 20. The connector assembly 20 has an outer body or connector nut 60 which supports a coaxial center conductor 61 positionally maintained and insulated therefrom by the insulator bushing 62. A spring receptacle 63 integral with the rearward end of the center conductor 61 rotationally engages the probe 39 with frictional contact to insure an electrical connection between the center conductor 61 and the probe 39. First and second axial bores 64 and 67 rotationally and frictionally receive the outer conductor 32 and the reduced diameter portion 33, respectively, of the connector 19. As shown herein, the union nut 22 encases the connector 19 and is threadedly engaged with the connector 20 such as to permit the coaxial cable 11 and its associated connector assembly 19 to rotate freely relative the connector assembly 20 and the union nut 22. The dust shield 27 and associated O-rings 23 and 68 protect the electrical connections within the connector apparatus from dust, moisture and other corrosion producing influences.

The preferred embodiment as herein described utilizes the outer conductor 32 and the connector nut 60 as a first set of electrical contacts between the outer conductor 14 of the coaxial cable and the device 10. The probe 39, engaged within the receptacle 63, functions as a second pair of electrical contacts to provide an electrical connection between the center conductor 17 and the center conductor 61. Although not herein illustrated, the center conductor 61 is received within the device 10 by a conventional phone jack type receptacle. The union nut 22 securely engages the connector assembly 20 to maintain the connector assembly 19 therewithin and insure electrical connection between the first and second pairs of contacts despite repeated cycles of relative rotation between the connector assembly 19 and the connector assembly 20 and the coaxial cable 11 and the device 10, respectively.

It will be readily apparent to those skilled in the art that the connector apparatus hereinafter described in connection with the preferred embodiment may be variously and alternately constructed. For example, the union nut 22 would function adequately by encasing the connector 20 and being fixedly secured to the connector assembly 19. Similarly, the connector assemblies 19 and 20 may assume reverse configurations wherein the connector assembly associated with the device is received within the connector assembly associated with the coaxial cable.

Claims

Having fully described and disclosed the present invention and the preferred embodiment thereof in such clear and concise terms as to enable those skilled in the art to understand and practice the same, the invention claimed is:

1. An assembly for connecting a coaxial cable to a fixed device, said coaxial cable including

an elongate tubular outer conductor, and

an inner conductor wire coaxially located within said tubular outer conductor and spaced therefrom by a dielectric,

said connector apparatus comprising a pair of connector assemblies, including:

a. a connector assembly to be fixedly secured to said coaxial cable including

i. a cylindrical outer conductor body having a plurality of contact members extending forwardly therefrom and a screw flight proximate the rear portion thereof,

ii. a collet within said outer conductor body and insulated therefrom to receive said inner conductor wire and having a probe extending forwardly therefrom,

iii. a collet closer associated with said collet,

iv. a compressible sleeve sized to receive said outer conductor, and

v. a nut having a bore to receive said cable therethrough and threadedly engageable with said outer conductor body,

said nut interacting with said sleeve and said collet closer as said nut is advanced along said screw flight to close said collet about said inner conductor wire and to clamp said sleeve about said outer conductor;

b. a connector assembly to be fixedly secured to said device including

i. an outer conductor body having a first axial bore therein sized to rotationally an frictionally receive said cylindrical outer conductor,

ii. a second axial bore within said outer conductor body sized to rotationally and frictionally receive said contact fingers, and

iii. a receptacle to rotationally and frictionally receive said probe,

said receptacle being electrically insulated from said outer conductor body; and

c. a union nut sized to rotatably encase one of said connector assemblies and engageable with the other of said connector assemblies to maintain said connector assemblies in mechanical and electrical connection.