The present invention relates generally to electrical connectors, and more specifically to coaxial connectors.
Coaxial cables are commonly utilized in radio frequency (RF) communications systems. Coaxial connectors are typically attached to the ends of cables to enable the cables to be connected with equipment or other cables. Connector interfaces provide a connect/disconnect functionality between a cable terminated with a connector and a corresponding connector with a mating connector interface mounted on an apparatus or another cable.
An RF coaxial connector interface commonly referred to as 4.3/10 is under consideration by the International Electrical Commission, an international standards body, to become a standardized coaxial connector interface as matter IEC(46F/243/NP). The 4.3/10 connector interface can be connected with a tool, by hand, or as a “quick-connect” connector. As shown in
Early adopters of the 4.3/10 connection interface have applied these connectors to communications equipment such as cellular base station antennas. In some cases, the same equipment includes connections for multiple types of connector interfaces, which are often selected based upon the diameter of each of the coaxial cables being connected to the device.
One of these alternative connectors is referred to as 4.1-9.5 or “Mini-Din” connector. The Mini-Din male connector 25 (shown on the right side of
In view of the foregoing, it may be desirable to provide an alternative connection interface that is compatible with existing 4.3/10 connectors.
As a first aspect, embodiments of the invention are directed to a similar interface blocking coaxial connector interconnectable with a 4.3/10 coaxial connector connection interface. The connector comprises: an inner contact defining a longitudinal axis; and an outer contact positioned radially outwardly from the inner contact and having axially-extending spring fingers. Each of the spring fingers includes a radially-inward protrusion projecting to an inner diameter less than an inner diameter of a male Mini-Din outer conductor cylinder.
As a second aspect, embodiments of the invention are directed to a similar interface blocking coaxial connector, interconnectable with a 4.3/10 coaxial connector connection interface, comprising: an inner contact that defines a longitudinal axis; and an outer contact with a distal end and a plurality of spring fingers. The distal end is located such that the distal end interferes with a Mini-Din connector before contact occurs between the spring fingers and an outer conductor cylinder of the Mini-Din connector.
As a third aspect, embodiments of the invention are directed to a similar interface blocking coaxial connector, interconnectable with a 4.3/10 coaxial connector connection interface, comprising: an inner contact defining a longitudinal axis; a cylindrical outer contact with a plurality of spring fingers; and a barrier plug retained proximate a distal end of the spring fingers that creates a stop face adjacent an inner diameter of the outer contact.
As a fourth aspect, embodiments of the invention are directed to a 4.3/10 coaxial connector configured to receive a mating 4.3/10 connector, comprising: an inner contact; a dielectric spacer; and an outer contact, the dielectric spacer separating the inner contact and the outer contact. The outer contact includes an outer wall and a plurality of spring fingers, the spring fingers configured to deflect radially inwardly when the mating 4.3/10 connector is mated. The connector further comprises blocking structure that prevents mating of a Mini-Din connector.
As a fifth aspect, embodiments of the invention are directed to a method of constructing a coaxial connector, comprising the steps of:
(a) identifying a coaxial connector, comprising: an inner contact configured to be mated with an inner conductor of a coaxial cable; an outer conductor body configured to be mated with an outer conductor of the coaxial cable, the outer conductor extension having a first outer body with a gap; wherein the gap is configured to receive a free end portion of a mating connector to establish an electrical connection; and wherein the first outer body includes first fingers that generally form a ring and deflect a first deflection distance radially inwardly during engagement of the coaxial connector with the mating connector, wherein the deflected first fingers exert a radially outward force on the mating connector, and wherein the first fingers have a first length, a first width, and a first thickness;
(b) selecting a second length, second width, and second thickness for second fingers of a second outer body, wherein the at least one of the second length, second width and second thickness differs from the first length, first width, and first thickness;
(c) selecting a second deflection distance for the second fingers; wherein the selections of steps (b) and (c) induce a radially outward force that is substantially the same as the radially outward force defined in step (a); and
(d) constructing the second outer body.
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 present invention is described with reference to the accompanying drawings, in which certain embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments that are pictured and described herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. It will also be appreciated that the embodiments disclosed herein can be combined in any way and/or combination to provide many additional embodiments.
Unless otherwise defined, all technical and scientific terms that are used in this disclosure have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the below description is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used in this disclosure, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that when an element (e.g., a device, circuit, etc.) is referred to as being “connected” or “coupled” to another element, it can be directly connected or coupled to the other element or intervening elements may be present. In contrast, when an element is referred to as being “directly connected” or “directly coupled” to another element, there are no intervening elements present.
As described above, erroneous mating of a Mini-Din connector with a 4.3/10 connector can damage the 4.3/10 connector to the extent that it becomes unusable. Below are described different approaches for a coaxial connector interface that is mechanically and electrically compatible with the 4.3/10 interface specification, but which inhibits erroneous interconnection with similar coaxial interfaces like the Mini-Din connector.
In one approach, it is recognized that, although the 4.3/10 interface includes a generally cylindrical space CS within the inner diameter of the fingers 12 of the outer contact 10 of the female connector 5 (best shown in
As shown in
The blocking surfaces 160 comprising the distal end of each of the outer contact spring fingers 112 may be generally planar (e.g., they may be aligned normal to a longitudinal axis of the outer contact 110). The blocking surfaces 160 may form a discontinuous annular arrangement, with an inner diameter that is less than the inner diameter of the male Mini-Din outer conductor cylinder 25, as shown in
The inwardly-projecting protrusions 155 may be present proximate the distal end as a lip or shoulder, or alternatively as a ramped surface wherein the thickness of the spring finger 112 increases from a proximal end to the distal end. Further, the inwardly-projecting protrusions 155 need not be applied to each of the outer contact spring fingers 112, but may omit some (e.g., every other spring finger 112 may lack a protrusion 155) to form a blocking face that effectively inhibits erroneous mating with a Mini-Din connector 25, as shown in
The outer contact 110 may be a machined element, or alternatively may be formed via metal stamping or the like.
Representative electrical modeling of the interface between the male 4.3/10 connector 20 and the female connector 105 demonstrates that the presence of the inward projecting protrusions 155 into the otherwise cylindrical space CS within the spring fingers 112 does not significantly degrade the electrical performance of an interface with the connector 105 compared to a conventional 4.3/10 connector interconnection (see
Referring now to
The amount of extension applied to the connector body 235 may be selected, for example, to coincide with the maximum extension which enables correct seating of the inner and outer contacts of the 4.3/10 female connector 205 with a male connector 20 according to the 4.3/10 interface specification. Limiting dimensions include, for example, that the inner contact 214 is able to seat at a longitudinal location along the male center pin 24 of the male 4.3/10 connector 20 that enables secure electrical contact to occur. To enhance this dimension further, the inner contact 214 of the female connector 205 may be provided with enhanced inward bias, enabling secure contact to be applied even to a conical end portion of the male center pin 24. This configuration can also allow for tolerance errors. Similarly, the outer contact 210 may be provided with a level of outward bias that enables the outer contact 210 to seat against at least a conical surface of interface cylinder 15 of a 4.3/10 male connector 20 (see
Because the outer diameter and surfaces of the outer contact 210 of the female connector 205 remain dimensionally unchanged, the connector 205 remains electromechanically compatible with the full range of male 4.3/10 connectors 20. However, the female connector 205 can improve protection against connector interface damage by providing a block against interconnection with the easily confused variants of the 4.3/10 connection interface without significantly impacting the electrical performance of the resulting interconnection.
Referring now to
The barrier plug 355 may be interlocked with the outer contact 310. As one example, an inward protrusion of the outer contact spring fingers 312 keys with an outer diameter groove 354 of the barrier plug 355 (shown in
To prevent the barrier plug 355 from interfering with the range of motion/outward bias of the spring fingers 312 required for secure engagement with the inner diameter of the conical surface of interface cylinder 15 of a 4.3/10 male connector interface (best shown in
One skilled in the art will appreciate that the fit between the outer surface 370 and the spring fingers 312 (combined with the elastomeric properties of the outer surface material that is selected, such as silicon or the like) may also be configured to increase the outward bias of the spring fingers 312, enabling a reduction in the bias properties required for the outer contact 310 alone. This configuration can enable the outer contact 310 to be provided with reduced dimensions and/or be formed of more cost efficient materials than may be possible without the presence of the barrier plug 355. Alternatively, the outer surface 370 may be provided as the relatively rigid/higher strength dielectric polymer while the interior ring 365 is provided as elastomeric dielectric polymer.
In further embodiments, a barrier plug 355″ may be formed as an axial extrusion of relatively rigid dielectric material positioned coaxially between the inner and outer contacts (see
One skilled in the art will appreciate that the application of a barrier plug 355, 355′, 355″ in the female connection interface of a 4.3/10 connector can improve protection against connector interface damage by providing a stop face against interconnection with the easily confused variants of the 4.3/10 connection interface, without significantly impacting the electrical performance of the resulting interconnection.
As another approach to addressing incorrect mating with a 4.3/10 female connector, it may be desirable to provide a design in which the spring fingers are less susceptible to deformation and breakage. To that end, an additional embodiment of a spring basket 410 for a connector 405 is shown in
It may be desirable for the fingers 412 to exert a similar radial force on the outer conductor body of a mating conductor as that exerted by the fingers 212 described above. For analytical purposes the fingers 412 can be approximated as cantilever beams. The force applied by a deflected cantilevered beam can be calculated as:
N=(3DEI)/L3 (1)
wherein
N=the force normal to the beam (in this instance, the radial force generated by the finger 412);
D=the amount of deflection experienced by the beam (i.e., the radial deflection of the finger 412);
E=elastic modulus of the material of the beam/finger 412;
I=moment of inertia through the cross-section of the beam/finger 412; and
L=length of the beam/finger 412.
Thus, for two fingers 412 formed of the same material (such that E is the same in both equations) to exert a similar radial force N on a mating outer conductor, the geometry of the fingers 412 and the overall spring basket 410 may be adjusted. For example, if it is desired to provide a more robust finger 412 that is less susceptible to breakage, the thickness of the finger 412 may be increased. However, increasing the thickness raises the moment of inertia I, which in turn increases the radial force. In addition, a shorter finger 412 may also be less inclined to break under an axial load; however, a decrease in length may also raise the radial force. One manner of addressing the increased radial load is to decrease the amount of deflection induced by mating of the fingers 412 with a mating connector, particularly if the thickness is increased.
For comparative purposes, in the embodiment of the outer conductor body 10 of
Notably, this concept can be applied not only to the spring basket discussed above, but also to other connectors conforming to the 4.3/10 interface guidelines that employ radial force between mating conductors, such as those shown in EP 2 304 851, incorporated herein by reference in its entirety.
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.
The present application is a continuation of and claims priority to U.S. patent application Ser. No. 16/688,417 filed Nov. 19, 2019, which is a continuation of and claims priority to U.S. patent application Ser. No. 15/963,684 filed Apr. 26, 2018, now U.S. Pat. No. 10,559,925, which is a continuation of and claims priority to U.S. patent application Ser. No. 15/141,526 filed Apr. 28, 2016, now U.S. Pat. No. 9,966,702, and claims the benefit of U.S. Provisional Patent Application Nos. 62/156,131, filed May 1, 2015, 62/157,328, filed May 5, 2015, 62/157,805, filed May 6, 2015, and 62/157,868, filed May 6, 2015, the disclosures of which are hereby incorporated herein in their entireties.
Number | Date | Country | |
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62156131 | May 2015 | US | |
62157328 | May 2015 | US | |
62157805 | May 2015 | US | |
62157868 | May 2015 | US |
Number | Date | Country | |
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Parent | 16688417 | Nov 2019 | US |
Child | 16986355 | US | |
Parent | 15963684 | Apr 2018 | US |
Child | 16688417 | US | |
Parent | 15141526 | Apr 2016 | US |
Child | 15963684 | US |