1. Field of the Invention
This invention relates to electrical cable connectors. More particularly, the invention relates to a coaxial connector with an anti-rotation characteristic with respect to the coaxial cable it is installed upon.
2. Description of Related Art
Coaxial cable connectors are used, for example, in communication systems requiring a high level of precision and reliability.
To create a secure mechanical and optimized electrical interconnection between the cable and the connector, it is desirable to have generally uniform, circumferential contact between a leading edge of the coaxial cable outer conductor and the connector body. A flared end of the outer conductor may be clamped against an annular wedge surface of the connector body, via a coupling nut, interlocking the connector and coaxial cable. Representative of this technology is commonly owned U.S. Pat. No. 5,795,188 issued Aug. 18, 1998 to Harwath.
Machine threaded coupling surfaces between the metal body and the coupling nut of U.S. Pat. No. 5,795,188 and similarly configured prior coaxial connectors significantly increase manufacturing costs and installation time requirements. Another drawback is the requirement for connector disassembly, sliding the back body over the cable end and then performing a precision cable end flaring operation, which retains the cable within the connector body during threading. Further, care must be taken at the final threading procedure and/or additional connector element(s) added to avoid damaging the flared end portion of the outer conductor as it is clamped between the body and the coupling nut to form a secure electrical connection between the outer conductor and the coaxial cable.
Alternative coaxial connector solutions, utilizing gripping/and or support elements about which the connector body is then radially crimped and/or axially compressed to secure an electromechanical interconnection between the outer conductor of the coaxial cable and the connector, are also known in the art. Crimped and/or compressed connections may be subject to varying quality depending upon the specific force level applied by the installer in each instance. Support surfaces added to prevent collapse of the outer conductor inserted within the inner diameter of the outer conductor, common in connectors for non-solid outer conductor coaxial cables, introduce an electrical performance degrading impedance discontinuity into the signal path. Further, crimping and/or compression becomes impractical with larger diameter coaxial cables, as the increased diameter, sidewall thickness and/or required travel of the corresponding connector/back body(s) increases the required force(s) beyond the levels deliverable by conventional crimp/compression hand tools.
If attached with less than a rigid rotational interlock between the connector and cable, rotation between the connector and cable may introduce electrical discontinuities, intermodulation distortion and/or compromise environmental seals surrounding the interconnection.
Competition in the coaxial cable connector market has focused attention on improving electrical performance and minimization of overall costs, including materials costs, training requirements for installation personnel, reduction of dedicated installation tooling and the total number of required installation steps and or operations.
Therefore, it is an object of the invention to provide a coaxial connector that overcomes deficiencies in the prior art while minimizing the opportunity for rotation between the connector and coaxial cable.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, where like reference numbers in the drawing figures refer to the same feature or element and may not be described in detail for every drawing figure in which they appear and, together with a general description of the invention given above, and the detailed description of the embodiments given below, serve to explain the principles of the invention.
The inventor has analyzed available solid outer conductor coaxial connectors and recognized the drawbacks of threaded inter-body connection(s), manual flaring installation procedures and crimp/compression coaxial connector designs.
As shown in a first exemplary embodiment in
The connector interface 23 may be any desired standard or proprietary interface.
One skilled in the art will appreciate that the cable end 15 and the connector end 25 are descriptors used herein to clarify longitudinal locations and contacting interrelationships between the various elements of the coaxial connector 1. In addition to the identified positions in relation to adjacent elements along the coaxial connector 1 longitudinal axis, each individual element has a cable end 15 side and a connector end 25 side, i.e. the sides of the respective element that are facing the respective cable end 15 and the connector end 25 of the coaxial connector 1.
The grip ring 19 may be retained within the connector body bore 5, for example seated within a grip ring groove 27. For ease of grip ring 19 (and further elements, if present, described herein below) installation and/or enhanced grip ring 19 to outer conductor 11 gripping characteristics, the grip ring groove 27 may be formed wherein the cable end grip ring groove 27 sidewall and/or bottom are surfaces of a clamp nut 31 coupled to the connector body 3, for example as shown in
The clamp ring 31, if present, may be coupled to the connector body 3 by a retaining feature 29, such as an interlock between one or more annular snap groove(s) 33 in the sidewall of the connector body bore 5 proximate the cable end 15 and corresponding snap barb(s) 35 provided on an outer diameter of the clamp ring 31, as best shown for example in
Clamp ring threads 37 between the connector body bore 5 and an outer diameter of the clamp ring 31 may also be provided as an alternative to the retaining feature 29. To enable the coaxial connector 1 to be supplied as a ready for installation assembly, the clamp ring threads 37 may be combined with the snap groove 33 and snap 35 interconnection to provide an assembly that may be supplied with the clamp ring 31 already attached to the connector body 3, preventing disassembly and/or loss of the internal elements, as shown for example in
As best shown in
As best viewed in
The contact between the outer diameter of the grip ring 19 and the wedge surface 39 may be along a corner of the grip ring 19 that may be rounded to promote smooth travel there along or alternatively the grip ring 19 may be formed with an extended contact area between the grip ring 19 and the wedge surface 39 by angling the outer diameter profile of the grip ring 19 to be parallel to the taper of the wedge surface 39.
As shown for example in
For ease of manufacture, for example of polymer material via injection molding, the bias tab(s) 69 may be formed as arc sections, enabling mold separation of the overhanging edge formed by the angle of the bias tab(s) 69 towards the connector end 15 by rotation and retraction.
The spring contact 21 may be any conductive structure with a spring characteristic, such as a helical coil spring, for example as shown in
The grip ring 19 is preferably formed from a material, such as stainless steel or beryllium copper alloy with a hardness characteristic greater than the material of the outer conductor 11, to enable the grip surface 17 to securely engage and grip the outer diameter of the outer conductor 11. The grip surface 17 of the grip ring 19 has a directional bias, engaging and gripping the outer diameter surface of the outer conductor 11 when in tension towards the cable end 15 while allowing the outer conductor 11 to slide past the grip surface 17 when moved towards the connector end 25. The grip surface 17 may be formed as a plurality of annular (
The grip ring 19 may be formed as a c-shaped ring, for example as shown in
The grip surface 17 may be provided with a profile matching the characteristic of a particular solid outer conductor 11, for example a concave curved profile dimensioned to mate with a corrugation trough of an annular corrugated solid outer conductor coaxial cable 13, as shown for example in
If the barb(s) 47 are provided in an annular configuration, and/or if the grip ring 19 outer diameter and wedge surface 39 are rotatable against one another a rotatable mechanical interconnection may result. A rotatable interconnection may lead to degradation of the electrical and/or mechanical interconnection properties. Where the grip ring 19 is c-shaped with a gap 18 between end(s) 20, the end(s) 20 may be provided as stop face(s) 51, for example by grinding to create a sharp edge, with respect to rotation of the grip ring 19 about the inner conductor 11.
To provide an additional anti-rotation characteristic to the interconnection, the barb(s) 47 may be provided with breaks in the annular aspect, such as one or more channel(s) 70, for example a shown in
The barb(s) 47 may also be formed with a longitudinal extent that is aligned generally co-planar with the coaxial connector 1 longitudinal axis, for example as shown in
The pocket(s) 77, gap 18 or other cavity of the grip ring 19 connector end 25 may also form a key into socket type rotational interlock with a spring contact 21, for example with tab(s) 81 bent towards the cable end 15 to mate with the pocket(s) 77, gap 18 or other cavity of the grip ring 19 and notch(s) 79 or the like on an outer diameter for an interference fit with the connector body 3, for example as shown in
As best shown in
Alternatively, the outer diameter of the wedge surface 39 may also be formed with barb(s) 47, with a longitudinal extent co-planar with a longitudinal axis of the coaxial connector 1, for example as shown in
To further stabilize the connector body 3 with respect to the outer diameter of the coaxial cable 13, a jacket grip 71 may be applied proximate the cable end 15 of the connector body 3, for example as shown in
When formed as helical grooves or barbs the jacket grip 71 may be threaded upon the jacket 57, providing assembly assistance to progressively move the outer conductor 11 under and past the spring contact 21 as the jacket grip 71 is threaded onto the jacket 57. The threading also assists with connector 1 to coaxial cable 13 retention.
An anti-rotation wedge surface 39 and grip ring 19 configuration may also be applied with respect to gripping of the jacket 57, in addition to and/or instead of the outer conductor 11. As shown for example in
One skilled in the art will appreciate that anti-rotation characteristics and the corresponding strengthening of the resulting interconnection between the coaxial cable 13 and the coaxial connector 1 is also desirable when applied to conventional coaxial connector configurations, such as outer conductor leading edge clamp type coaxial connectors, for example as shown in
Operational aspects of the grip ring 19 and wedge surface 39 interaction will now be described in detail. The grip ring 19 has a range of longitudinal movement within its respective grip ring groove 27, for example as shown in representative
Conversely, once spread, the bias of the grip ring 19 inward towards its relaxed state creates a gripping engagement between the grip surface 17 and the outer diameter surface of the outer conductor 11 or jacket 57. If tension is applied between the connector body 3 and the coaxial cable 13 to pull the outer conductor 11 and/or jacket 57 towards the cable end 15, the grip ring 19, engaged via the grip surface 17, is driven against the tapered wedge surface 39, progressively decreasing the depth of the grip ring groove 27, thereby driving the grip ring 19 radially inward and further increasing the gripping engagement as the respective grip surface 17 is driven into the outer diameter surface of the outer conductor 11 or jacket 57. A cable end 15 grip ring groove 27 sidewall may be dimensioned to be at a position where the grip ring 19 diameter relative to the outer conductor 11 diameter is configured for the grip surface 17 to have securely engaged the outer conductor 11 or jacket 57 but which is short of the respective grip ring 19 radial inward movement which may otherwise cause the outer conductor 11 to collapse radially inward and/or unacceptably compress the jacket 57.
During coaxial cable 13 interconnection with embodiments including a clamp ring 31 and a retaining feature 29 including the clamp ring threads 37, for example as shown in
Elastic characteristics of the outer conductor seal 45, if present, may also impact ease of installation and the final sealing characteristics. For example, where the outer conductor seal 45 is provided on the connector end 25 side of the grip ring 19, for example as shown in
A jacket seal 53 may be provided in a jacket groove 53 proximate the cable end 15 of the coaxial connector 1. The jacket seal 53 is dimensioned to seal between the connector body bore 5 or clamp ring 31, if present, and the jacket 57. If a clamp ring 31 is present, a further clamp ring seal 59 seated in a clamp ring groove 61 may be provided to seal between the clamp ring 31 and the connector body 3.
One skilled in the art will appreciate the significant manufacturing and installation benefits of the present invention. During manufacturing, a complete coaxial connector 1 assembly ready for installation is prepared with a minimal total number of required elements. If a clamp ring 31 is included in the configuration, the installation of the spring contact 21, spacer 43, grip ring 19 and/or outer conductor seal 45 is simplified by the improved access to the grip ring groove 27, that may then be easily closed by snapping/threading the clamp ring 31 in place after the desired sub elements have been seated in the open end(s) of the connector body bore 5 and/or clamp ring 31. Further, the various environmental seals (outer conductor seal 45, jacket seal 53 and or clamp ring seal 59) may be each overmolded upon the respective groove(s) to provide a single assembly with integral environmental seals. Hole(s) 62 may be formed from the outer diameter to the inner diameter of the clamp ring 31, enabling the outer conductor seal 45 and clamp ring seal 59 to overmolded as a unitary inter-supporting gasket, best shown in
To install the coaxial connector 1 upon a coaxial cable 13, the coaxial cable end is stripped back to expose desired lengths of the conductor(s) and the stripped coaxial cable end inserted into the cable end 15 of the connector body bore 5 until bottomed. If present, the clamp ring 31, if including clamp ring threads 37, is then threaded towards the connector body 3 and a test tension between the connector body 3 and the coaxial cable 1 applied to verify secure engagement between the grip ring 19 and the outer conductor 11.
Coaxial connector 1 embodiments with a threaded clamp ring 31 may be uninstalled from the coaxial cable 13 for interconnection inspection and/or reuse by unthreading the clamp ring 31 away from the connector body 3, enabling the grip ring 13 to move outward and away from engagement with the outer conductor 11 as the wedge surface 39 shifts toward the cable end 15 with the clamp ring 31. When the grip ring 13 has disengaged, the coaxial cable 13 may be withdrawn from the connector body bore 5.
Where in the foregoing description reference has been made to materials, ratios, integers or components having known equivalents then such equivalents are herein incorporated as if individually set forth.
While the present invention has been illustrated by the description of the embodiments thereof, and while the embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, representative apparatus, methods, and illustrative examples shown and described. Accordingly, departures may be made from such details without departure from the spirit or scope of applicant's general inventive concept. Further, it is to be appreciated that improvements and/or modifications may be made thereto without departing from the scope or spirit of the present invention as defined by the following claims.
This application is a continuation-in-part of commonly owned U.S. Utility patent application Ser. No. 12/611,095, titled “Insertion Coupling Coaxial Connector”, filed Nov. 2, 2009 by Jeffrey Paynter and Al Cox, currently pending, hereby incorporated by reference in its entirety, which is a continuation-in-part of commonly owned U.S. Utility patent application Ser. No. 12/264,932, titled “Insertion Coupling Coaxial Connector”, filed Nov. 5, 2008 by Jeffrey Paynter and Al Cox, currently pending, hereby incorporated by reference in its entirety.
Number | Date | Country | |
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Parent | 12611095 | Nov 2009 | US |
Child | 12612428 | US | |
Parent | 12264932 | Nov 2008 | US |
Child | 12611095 | US |