PHASE-ADJUSTABLE COAXIAL CABLE CONNECTOR

Abstract: A coaxial cable connector 1 has a cylinder body 2 supporting a rotatable coupling 4 at one end and an adjustment element 8 screwthreaded to the body 2 at its opposite end. An electrically conducting central connecting element 13 is supported within the forward end of body 2 by dielectric 12. A centre conductor 11 of the cable 9 is connected to the central connecting element 13, and rotation of element 8 relative to body 2 moves the coaxial cable axially relative to central connecting element 13 to vary the axial length of the central conducting path, by kinking the central conductor or otherwise.

Description: The present invention relates to a coaxial cable connector which facilitates phase adjustment at terminal assembly of a coaxial cable. Coaxial connectors which are intended for interconnection of the ends of coaxial cables are known in the art and described, for example, the German patent document DE-C-915 100. In the case in which coaxial connectors are used in a coaxial cable assembly incorporated into a phase-array system of a radar which requires a predetermined phase, the coaxial connector is usually attached to one end of the coaxial cable, which preliminarily is provided with an excess length, which is then cut to a predetermined length on the basis of measurement of the phase by means of a pulse-reflection method. After matching the phase to a required value, another coaxial connector is attached to the opposite end of the cable. This is a very lengthy and inefficient procedure, which may lead to high expenses, especially in those cases where the cable is occasionally cut to a lenght which is shorter than actually required. The present invention seeks to eliminate the disadvantages inherent in the prior art devices and by providing a coaxial cable connector which permits adjustment of the phase of the cable without wastage of cable, and after connection is made. According to the present invention there is provided a coaxial cable connector comprising a cylindrical connector body of conductive metal supporting a metal coupling at one end of said connector body, the coupling being rotationally but not axially moveable with respect to said connector body, said connector body being threadingly engaged at its other end with a coaxial cable support member, said support member supporting a coaxial cable therein, which cable has a centre conductor and a conducting shield separated by a dielectric material, said centre conductor extending beyond said coaxial cable and into said connector body and having a bendable portion disposed within said connector body, said portion being affixed to a central connecting and conducting pin element therein extending into said coupling, said pin element being supported within said coupling by a dielectric material which separates said coupling and said element, said element being rotationally moveable within said dielectric, whereby, rotational movement of said coaxial cable support member relative to said connector body results in axial displacement of said support member with respect to said connector body thereby causing more or less slack in said bendable portion and providing means for adjusting the electrical path length of said connector to permit phase adjustment. The present invention also provides a coaxial cable connector comprising a cylindrical connector body of conductive metal supporting a metal coupling at one end of said connector body, the coupling being rotationally but not axially moveable with respect to said connector body, a coaxial cable support member supporting a coaxial cable being engaged at the other end of said connector body, said support and connector body being rotatably moveable with respect to each other, said coaxial cable having a centre conductor and shield separated by a dielectric material, said centre conductor extending into said connector body and being affixed to a contact element therein, said contact element being threadingly engaged with a central connecting and conducting pin element extending into said coupling and being supported within said coupling by a dielectric material which separates said coupling and said central connecting element, whereby rotational movement of said coaxial cable relative to the connector body results in axial displacement of said contact member with respect to said central connecting and conducting pin element therby providing means for adjusting the electrical path length of said connector to permit phase adjustment. The connector may have at least one impedance-adjusting screw threaded into the connector body. The invention will now be particularly described, by way of example, with reference to the accompaying drawings in which:- Figure. 1 is a side elevational view, partly in cross section, of a phase-adjustable coaxial connector in accordance with one embodiment of the present invention, and Figure 2 is a similar representation of a coaxial connector in accordance with another embodiment of the invention. A phase-adjustable coaxial cable connector is provided in which phase adjustment is obtained by means which increase or decrease the axial length of the conductive path between a pin element at one end of the connector and the coaxial cable which extends into the connector. In preferred embodiments of the present invention, a phase-adjustable coaxial connector has a cylindrical connector body in which a central connecting pin element is supported by one end of the connector body through an insulation. An adjustable element which is supported by the other end of the connector body and contains a coaxial cable, can be moved axially with respect to the connector body while maintaining electrical contact therewith, and while maintaining electrical contact between the pin element and the centre conductor. In one embodiment, an exposed length of the centre conductor between the pin element and the coaxial cable can kink to permit phase adjustment. In another embodiment, the centre conductor is connected by a screw coupling to the pin element so that relative rotation between the centre conductor and the pin element shortens or lengthens the screw coupling. Connectors of the above-mentioned types are advantageous in that by attaching the central conductor of the coaxial cable to the central connecting element of the connector and by effecting relative axial movement, it is possible to adjust the phase of the coaxial cable and at the same time to protect the central conductor from concentration of stress. The connector body may have impedance-adjusting screws moveable with respect to the central conductor. These screws can be used for compensation of deviations in the value of the characteristic impedance. In the device of the invention, because the adjustment element which supports one end of the coaxial cable is moveable axially with respect to the connector cylinder, it becomes possible to provide microscopic adjustment of the length (i.e. the electric length, and hence the phase-path length) of the cable assembly. In the illustated embodiment of Figure 1, the coaxial connector 1 has a connector cylinder body 2, which is made from a conductive material, in particular metal. Cylinder 2 supprts at its one end a coupling 4 which can rotate around the cylinder, but is restrained against axial movement by a cotter ring 3. The external part of coupling 4 is preferably formed as a hexagonal nut which can be rotated by a tool. By means of a female thread 6, which is formed inside coupling 4, the latter can be attached to an appropriate male connecting counterpart, for example on an instrument. Coupling 4 is made of a conductive material such as metal, so that it is electrically connected to an external conductor 10 of a coaxial cable 9 through connector cylinder 2 and an adjustment element 8. Central conductor 11 of coaxial cable 9 is electrically connected with a central connecting element 13 which is supported in connector cylinder 2 by a dielectric body 12. In establishing electrical contact between central conductor 11 and connecting element 13, central conductor 11 is preliminarly slackened or bent at a portion 14 and is then fixed in connecting element 13 by soldering. For this purpose, connecting element 13 has a solder feeding opening 15. External conductor 10 of coaxial cable 9 is connected to adjustment element 8 electrically and mechanically by soldering. For this purpose, adjustment element 8 has in its wall a through opening 16 for the supply of the solder. Adjustment element 8 has on its periphery a male thread 18 which is screwed into a female thread 17, formed inside connector cylinder 2 on the side opposite to coupling 4. The above-mentioned threaded connection makes it possible to adjust the length (i.e. the electrical length) of the entire cable assembly. In the embodiment of Figure 1 the front end of coaxial cable 9 with the outer sheath 20 is supported by the connector through a recess 19 cut in the adjustment element on the end opposite to thread 18. To this end, the front end of the coaxial cable coated with sheath 20 is inserted into recess 19. It is understood, however, that other types of connections can be used for this purpose. For example, the end of the cable can be threaded or pressed into a cable-supporting ring (not shown). With phase-adjustable coaxial cable connector 1 of the above-described type, after assembling the connector with coaxial cable 9, the microscopic adjustment of the phase variation of the phase of the cable, i.e. of its electric length, is performed by rotating adjustment body 8 with respect to cylinder body 2. The adjustment makes it possible to match the arbitrary characteristic impedance, which is determined by the amount of extension of kinked portion 14 of central conductor 11, with the characteristic impedance of coaxial cable 9. Variations can be compensated by impedance-adjusting screws 21 which are threaded into connector cylinder 2 towards the central conductor. In the embodiment of Figure 2 a central coupling of adjustable axial length is provided. Central conductor 11 is attached mechanically and electrically to a contact element 22 by soldering. The soldering is performed by supplying solder through opening 23. Contact element 23 is provided on its outer periphery with a male thread 24, and is supported in the connector cylinder 2 through a dielectric body 25, which supports a central connector 26, having a female thread 27 engaged with the thread 24. When the adjustment element 8 is rotated and therefore moved axially, i.e. when coaxial cable 9 is rotated, this movement causes rotation of contact element 22 as well. Thus contact element 24 is screwed into ro out of central connector 26 thereby forming the adjustable coupling. As a result, the electric length of the coaxial cable, i.e. of central conductor 11 is changed. In this embodiment, contact element 22 and central connecting element 26 are interconnected through a thread, but instead of this, they may have a sliding electric contact. The use of the coaxial connector of the above-described types suggests the following effects; (1) Assembly time is shortened: (2) Assembly does not require skilled labour: (3) The cable is not damaged; (4) Because the connector allows for multiple adjustments, mistakes can be corrected, and the connector possesses high utility; and (5) When the phase is adjusted by attaching the connectors to both ends of the cable, the measurements can be checked by a pulse-passage method. This improves the accuracy of adjustment.

Claims: A coaxial cable connector comprising a cylindrical connector body (2) of conductive metal supporting a metal coupling (4) at one end of said connector body, the coupling being rotationally but not axially moveable with respect to said connector body, said connector body being threadingly engaged at its other end with a coaxial cable support member (8), said support member supporting a coaxial cable (9) therein, which cable has a centre conductor (11) and a conducting shield separated by a dielectric material, said centre conductor extending beyond said coaixal cable and into said connector body and having a bendable portion (14) disposed within said connector body, said portion being affixed to a central connecting and conducting pin element (13) therein extending into said coupling, said pin element being supported within said coupling by a dielectric material (12) which separates said coupling and said element, said element being rotatinally moveable within said dielectric, whereby rotational movement of said coaxial cable support member relative to said connector body results in axial displacement of said support member with respect to said connector body thereby causing more or less slack in said bendable portion and providing means for adjusting the electrical path length of said connector to permit phase adjustment. A coaxial cable connector comprising a cylindrical connector body (2) of conductive metal supporting a metal coupling (4) at one end of said connector body, the coupling being rotationally but not axially moveable with respect to said connector body, a coaxial cable support member (8) supporting a coaxial cable (9) being engaged at the other end of said connector body, said support and connector body being rotatably moveable with respect to each other, said coaxial cable having a centre conductor (11) and shield separated by a dielectric material, said centre conductor extending into said connector body and being affixed to a contact element (22) therein, said contact element being threadingly engaged with a central connecting and conducting pin element (26) extending into said coupling and being supported within said coupling by a dielectric material (25) which separates said coupling and said central connecting element, whereby rotational movement of said coaxial cable relative to the connector body results in axial displacement of said contact member with respect to said central connecting and conducting pin element thereby providing means for adjusting the electrical path length of said connector to permit phase adjustment. A coaxial cable connector according to claim 1, or claim 2 having at least one impedance-adjusting screw (21) threaded into said cyclindrical connector body.

Inventors: YASUMOTO, HIROMI
Applicants: JUNKOSHA CO. LTD.
Application year: 1987
Main classification: H01R17
IPC codes: H01R24, H01R13