Patent Application
20160329643
The invention relates generally to a connector and cable interconnection. More specifically, the invention relates to a soldered connector and cable interconnection.
U.S. Pat. No. 5,802,710 discloses an electrical connector for use with coaxial cable and a method for attaching same. The connector may be attached to the coaxial cable with a high level of quality control via an assembly apparatus, as disclosed in commonly owned U.S. Pat. No. 7,900,344. The connector utilizes an insulating disc retained upon the inner connector and against the dielectric layer and outer conductor of the cable. Induction heating of a solder preform wrapped around the outer conductor creates a molten solder pool in a cylindrical solder cavity formed between the outer conductor, the insulating disc and the outer body of the connector. The insulating disc prevents the molten solder from migrating out of the cavity, which could foul the connector bore and/or short the outer and inner conductors. U.S. Pat. No. 8,984,745 discloses a variation of U.S. Pat. No. 7,900,344, supra, wherein a close-fitting interface pedestal provides the sidewall of the solder cavity in the solder apparatus, enabling elimination of the insulating disc.
Passive Intermodulation Distortion (PIM) is a form of electrical interference/signal transmission degradation that may occur with non-symmetrical interconnections and/or as electro-mechanical interconnections shift or degrade over time (for example, due to mechanical stress, vibration, thermal cycling, corrosion and/or material degradation). PIM is an important interconnection quality characteristic, as PIM generated by a single low quality interconnection may degrade the electrical performance of an entire RF system.
Competition within the cable and connector assembly industry has increased the importance of improving the electro-mechanical characteristics of the cable and connector interconnection while easing requirements for proper assembly.
As a first aspect, embodiments of the invention are directed to a cable-connector assembly, comprising: a coaxial connector having an outer connector body with a solder bore; a coaxial cable having an inner conductor and an outer conductor, the outer conductor seated within the solder bore; and a PIM block comprising an annular seat and a generally cylindrical flange extending from an outer periphery of the annular seat along a longitudinal axis of the annular seat. A leading edge of the outer conductor of the cable is inserted within the flange of the PIM block. An outer diameter of the outer conductor is coupled to an inner diameter of the solder bore via a solder joint.
As a second aspect, embodiments of the invention are directed to a method for interconnecting a connector and a coaxial cable with an outer conductor; comprising: providing a coaxial cable having an inner conductor and an outer conductor, the outer conductor having a leading edge; providing a connector having an outer body with a solder bore; providing a PIM block having a generally annular ring and a generally cylindrical flange; seating the leading edge of the outer conductor within the cylindrical flange; inserting the PIM block and coaxial cable into the solder bore of the connector; and soldering an outer diameter of the outer conductor to an inner diameter of the solder bore.
As a third aspect, embodiments of the invention are directed to a table-connector assembly, comprising: a coaxial connector having an outer connector body with a solder bore; a coaxial cable having an inner conductor and an outer conductor, the outer conductor seated within the solder bore; and a PIM block comprising an annular seat and a generally cylindrical flange extending from an outer periphery of the annular seat along a longitudinal axis of the annular seat. A leading edge of the outer conductor of the cable is inserted within the flange of the PIM block and seated against the annular seat.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention 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.
It has been recognized that the insulating disc relied upon in prior connector and assembly apparatus to provide the molten solder containment during interconnection (as discussed in the patents noted above) can introduce an impedance discontinuity that may degrade the electrical performance of the resulting interconnection. Analysis of soldered interconnections such as those described in U.S. Pat. No. 5,802,710, supra, and shown in
Further, inspection of disassembled conventional solder joints has revealed that, although straightening steps may be applied to remove bends present as the bulk coaxial cable is unwound from supply reels, the coaxial cable 20 typically still is not perfectly straight when the interconnection is soldered, as demonstrated in
A cable end PIM block 50, a replacement for the conventional insulating disk 5 of
As can be seen in
Further, as there is not a path between the outer conductor 115 and the inner conductor 110 along the surface of the end face 45, any flow of rosin/flux upon heating for soldering is inhibited from flowing around the inner diameter of the end face 45. As such, there is no residue pathway previously observed with a conventional insulating disc and the attendant lowered voltage breakdown potential of the cable and interconnection.
In addition, use of an end face 45 having a bore size similar to that of the inner diameter of the outer conductor 115 can also maintain the voltage breakdown potential of the cable outer conductor 115 and the inner conductor 110 that the cable was designed for by not having the higher dielectric constant PIM blocks 50, 50′ and the dielectric layer (typically foamed) of the cable 110 in contact (as is the case in the prior cable shown in
The inner diameter of the cylindrical flange 40 is dimensioned to receive the leading edge of the outer conductor 115 in a close fit, and the outer diameter of the cylindrical flange 40 is dimensioned for close fit with the inner diameter of the solder bore 155. Thus, when the leading edge of the outer conductor 115 is seated within the seat 60, the outer conductor 115 is held aligned coaxial with the inner diameter of the solder bore 155 and is entirely insulated from contact with the solder bore 155; in addition, the center pin 130 is aligned and does not create an off-center bias. Thus, the coaxial alignment of the outer conductor 115 with the solder bore 155 can result in a solder joint 65 in which the electro-mechanical interconnection has no stray edges that may cause scraping or migration that may otherwise generate PIM. Further, if a cable end air/gas pocket 135 is present at the end of the outer conductor 115 once soldering is completed, any movement of the end of the outer conductor 115 within the seat 60 will not generate PIM, as no shift in metal-to-metal contact occurs.
The PIM blocks 50, 50′ of
One skilled in this art will appreciate that the PIM blocks 50, 50′ may be utilized with coaxial cables 120 with a wide range of outer conductors 115, such as solid outer conductors, foil outer conductors, and/or woven outer conductors, any of which may have straight or corrugated configurations.
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 claims priority from and the benefit of U.S. Provisional Patent Application No. 62/158,374, filed May 7, 2015, the disclosure of which is hereby incorporated herein in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 62158374 | May 2015 | US |
