The invention relates to a connector according to the preamble of claim 1 and a connector assembly according to the preamble of claim 16.
Connectors in general are used to disconnect and/or connect electrical lines, in order to transmit current and/or primarily electrical signals thereby. The connectors may be multiple or single connectors.
Coaxial connectors are extremely important in the field of connectors. They have an inner conductor and an outer conductor and usually comprise an outer-conductor shield, with a dielectric normally being used to isolate the inner conductor galvanically from the outer conductor. Instead of a dielectric in the form of a solid object, it is also possible to use cable insulation to hold the inner conductor in a central position.
The huge range of coaxial conductors are classified according to application.
For instance, the following connectors are known in the field of radio frequency engineering: BC connectors, F connectors (for example for radio frequency transmission up to 5 GHz), SMA connectors (for frequency ranges from 1 to 18 GHz), UHF connectors and, for instance, also 7-16 (DIN) connectors based on IEC standard EN 60 169-4.
In particular, the latter connectors, the 7-16 (DIN) connectors based on IEC standard EN 60 169-4, are robust RF connectors that are generally used up to 7.5 GHz for example. They are primarily used with higher RF powers when the mechanical connection is also exposed to environmental conditions. Hence these connectors are mainly also employed in antenna technology and, in this case, particularly also in mobile radio communication systems such as base stations.
According to the DIN standards, connectors can be designed both with a pin contact and with a socket contact. A pin contact (male contact) is a contact for which electrical contact is made on the outer surface of the contact part (pin). A connector having a socket contact (female contact) involves a contact for which electrical contact is made on the inner surface of the contact part. The types of connector can be classified as a plug or a coupler: a plug is a connector that comprises the moving part of the locking mechanism; the coupler is the mating part to the plug, and is sometimes also called the “socket”. A coupled connector assembly ultimately comprises two or more connectors that are connected together, if necessary using an intermediate connector or connecting parts (in the case of a connector using connecting parts).
Thus a coupled connector assembly, as is also known, for example, from DE 18 13 161 U, comprises two coupled connectors, wherein the one connector, for example, may be a connector having a pin contact (i.e. characterised by a pin-shaped inner-conductor plug) and the other connector may be a connector having a socket contact (characterised by its inner-conductor socket contact). In principle, the connectors could also be designed with an hermaphroditic contact, for which the inner conductors in both coupled connectors have the same design or else cannot be described as either pin-shaped or socket-shaped. When the plug and socket are plugged together axially, contact is made between the inner conductors and corresponding contact is made between the outer conductors.
If two connectors are to be coupled together, they can be plugged together, i.e. pushed together, so far axially until an associated outer-conductor ring comes up against an axial stop limit on an outer conductor of the other connector (front face), and this also guarantees that electrical contact is made between the outer conductors of the two connectors to be coupled.
In order to guarantee good intermodulation properties for such radio frequency connections (RF connections), it is necessary for high contact pressures or capacitive couplings to be present between the components. The compact construction of connectors means that capacitive couplings are mostly not possible because there is not enough space here. In addition, capacitive couplings often have a radio frequency bandwidth that is too narrow and they do not allow any DC transmission and/or data transfer.
High contact pressures have the disadvantage that very high-quality materials need to be used that can withstand the high pressures. Hence, for example, a plastic outer conductor cannot be used in a 7-16 (DIN) connector based on IEC standard EN 60 169-4, i.e. it is not possible to use a plastic outer conductor coated in a conducting layer or a plastic coupling nut to make a permanent, tight axial connection between plug and socket, because this cannot guarantee the same mechanical and electrical properties over prolonged periods (especially also when one considers that such a connection may potentially be exposed to large temperature variations). The relaxation that occurs particularly with plastic would result in a change in the mechanical contact pressure and hence also in a change in the electrical properties. Such situations give rise especially to intermodulation problems, which need to be avoided at all events.
For intermodulation measurements (IM measurements), the RF connectors must also always be tightened with a minimum torque in order that the recommended contact pressure is achieved. The high tightening torque is also necessary in order to compress the integral seal.
Proceeding from this prior art, it is the object of the present invention to create an improved connector (having pin contact and/or having socket contact), and at the same time the improved connector shall preferably be compatible for connection, i.e. the connector improved according to the invention shall preferably be able to interact without difficulty with the respective standardised mating part, which means that the standardised mating part to the connector modified according to the invention does not itself need to be adapted. Thanks to this backwards compatibility, it is possible to fit and to use connectors according to the invention also with conventional interacting connectors. In addition, the invention shall not only improve a connector or two interacting connectors, but shall also create an improved, coupled connector assembly.
As regards the connector according to the invention, the object is achieved according to the features given in claim 1, and as regards the (coupled) connector assembly according to the invention, the object is achieved according to the features given in claim 16. The subclaims contain advantageous embodiments of the invention.
The present invention takes a completely new approach, which produces surprising and considerable advantages over the prior art.
The crux of the invention is that the mechanically imposed stop limit, which limits relative to each other the maximum insertion distance, i.e. the insertion depth, between two connectors to be coupled, is separated from the function of making electrical contact between the two outer conductors, which interact in the coupled state, of the connectors.
According to the prior art, even to carry out measurements, sufficiently high torques had to be exerted continuously on a coupling nut on the connector concerned in order thereby to hold in contact the one connector, e.g. having the pin contact (which, for the sake of simplicity, is referred to below for short as a pin-shaped connector or even more succinctly as a plug), with the other connector, e.g. having the socket contact (which is referred to below also for short as a socket-shaped connector or sometimes even more succinctly as a socket), by sufficient axial forces, with the connectors interconnected as far as the stop. This is because applying the sufficiently high torques to produce the sufficiently high axial contact pressures between the outer-conductor sections of the two connectors that can be coupled together is necessary in order to guarantee the appropriate contact pressure to produce the desired electrical contact between the outer conductors of the two interacting connectors.
This function is now separated according to the invention. Whilst a stop limit is provided to make the mechanical connection between the plug-shaped connector and the socket-shaped connector, the electrical signal path is separate therefrom, so that it is already guaranteed that sufficient, uniform and constant outer-conductor contact is made between socket and plug even when the plug-shaped connector and socket-shaped connector are still not completely interconnected and a provided coupling nut is still not tightened into its final position.
The generic document DE 18 13 161 U shows a plug for coaxial RF connections in which the one outer-conductor contact part, which contains slits parallel to the axis and is designed to have an outwards spring action, has contact segments that protrude radially outwards, which interact with the inwards-facing surface of the second outer conductor of the second contact part. However, the spring-loaded tabs provided with the contact segments at the same time also rest in an axial direction with their leading front end against a corresponding annular shoulder of the outer conductor of the second contact part, and therefore not only does this axial stop set up the axial pressures but it also establishes the RF signal path. This is because the RF signal path always spreads over the inside surfaces (which are not shielded from the interior) of the outer conductors between which contact is to be made, so that in this case the RF signal path is only made via the axial stop between the two outer conductor sections between which contact is to be made, while the contact segments projecting radially outwards in the form of annular contact ridges are irrelevant to the RF signal path.
This means that the disadvantages described with regard to the prior art remain, whereby high tightening torques for the front contact between the outer conductor of the socket-shaped connector with the outer conductor of the pin-shaped connector are no longer necessary, because now electrical contact is not made axially (the axial mechanical stop limit between the two connectors to be coupled), but separately therefrom, radially via contacts, in particular via spring contacts.
In addition, the invention has the following advantages:
In other words, the invention can be applied to connectors or (coupled) connector assemblies, one connector of which has a socket outer-conductor contact (for which contact is made on the inner surface of the contact part) and the respective other connector has a pin outer-conductor contact (for which electrical contact is made on the outer surface of the contact part). When mention is made of a pin-shaped contact or pin outer-conductor contact, this means that, with reference to the outer conductor, the pin-shaped contact is sleeve-shaped or like a sleeve in form, because said inner-conductor contact-making between the two connectors is again provided inside said pin-shaped contact. The invention can also be applied to pin contacts or socket contacts (unattached connectors, connectors to cables, fixed connectors etc.). The types of connectors can here be said plugs or couplers (sockets). In particular, the invention can also be applied to intermediate connectors or adapters.
The invention is described in more detail below with reference to drawings, in which specifically:
a shows a development of the outer conductor of the coupler in an exemplary embodiment that differs from
a shows an exemplary embodiment that differs slightly from
First, a coupled connector assembly according to the prior art having two interconnected connectors shall be presented and described with reference to
The coupled connector assembly shown in
The connector 100 referred to sometimes as a coupler 100 comprises for this purpose a socket-shaped inner conductor 101 comprising a socket-shaped inner-conductor spring cage 103. This socket-shaped inner-conductor spring cage 103 has a plurality of generally axial slits 105 around the circumference, which extend from the open end of the inner conductor 101 over a certain axial distance, thereby forming individual inner-conductor contact springs 107 present in the inner conductor socket 101.
This socket inner conductor 101 is held by means of a socket insulator or socket insulator ring 109 lying offset in the unattached inner-conductor spring cage 103, and is thereby galvanically isolated from the socket outer conductor 113. Said socket insulator ring 109 is referred to below sometimes also as the socket-end centering washer 109. As a different option, the cable-centering mechanism of a cable connected to the connector can also be used to hold the inner conductor in the centre.
The coupler outer conductor 113 encircles the coupler inner conductor 101. The coupler outer conductor 113 is designed here in the form of a coupler outer-conductor housing 115 and has an external thread 117 on its outer circumference along an axial partial length.
In addition, an annular outer-conductor groove 119 is made in the coupler outer conductor 113 that runs from the contact-making and plug end of the outer conductor (the end that faces downwards in
In the illustrated example, the front face 123 on the coupler outer-conductor contact-making section 121 extends beyond the front face 125 on the coupler outer-conductor threaded section 117.
A coupler 100 of this form can be interconnected with said plug 200 in an axial direction 300. The coupler 100 hence likewise has a connecting or insertion end on the end facing the coupler, via which the two connectors, one in the form of the coupler 100 and one in the form of the plug 200, can be interconnected.
The plug 200 here comprises a plug inner conductor 201, which is plug-shaped or pin-shaped in form, and which in the contacted state engages in the coupler inner-conductor spring cage 113, whereby the contact made by the inner-conductor contact springs 107 of the coupler with the outer circumference of the plug inner conductor 201 can make the galvanic contact between the inner conductor of the socket and the inner conductor of the plug. The axial overlap between the inner-conductor spring cage 113 of the socket and the pin-shaped or plug-shaped inner conductor 201 of the plug is provided to a sufficient extent.
This plug inner conductor 201 is encircled by a plug outer conductor 213, the plug inner conductor 201 being held and galvanically isolated from said plug outer conductor in a manner similar to that in the coupler by means of a plug insulator, a plug insulator ring 209 or what is called a plug-end centering washer 209, wherein the centering washer can be made of (any) suitable material, for example of plastic. In this case it is again possible to dispense with the insulator 209 if the cable insulation is used to hold the inner conductor in a central position.
The plug outer conductor 213 has a ledge or annular ledge 215 projecting radially inwards, which, facing the coupler 100 in an axial direction, forms in the illustrated embodiment an annular stop shoulder 217.
Likewise, a ledge or annular ledge 219 projecting radially outwards is provided on the plug outer conductor 213, which, facing the coupler 100 in an axial direction, similarly forms an external shoulder 221 which is annular in the illustrated embodiment.
In addition, a coupling nut 223 is provided, which is made in the form of a coupling cap or the like, which is provided with a lip 223a on the front end, by means of which the plug can be carried along with its outer conductor, for example by means of the outwards-projecting ledge 219, when the coupling nut 223 is screwed onto the external thread 117 on the coupler outer-conductor housing 115 by its internal thread 227. Said coupling nut 223 can also be provided, however, on the other connector, i.e. on the coupler 100.
To produce a mechanically sufficiently tight connection, suitably high torques must be exerted on the coupling nut 223 until the plug and the coupler are pressed against each other by sufficiently high axial forces at their stop limit acting in the axial direction, whereby the maximum interconnection travel (insertion depth) is limited. When tightening the coupling nut 223, it is in fact the front face 123 of the annular outer-conductor contact-making section 121 of the coupler that comes up against the stop shoulder 217 of the plug 200, and produces here the maximum axial tensioning forces, induced by the torque, between the outer conductor of the coupler 100 and of the plug 200. The electrical signal path is simultaneously established here between the front face 123 of the coupler outer-conductor contact-making section 121 and the electrically conducting stop shoulder 217 of the plug 200.
It can also be seen from the drawings that the plug outer conductor 213 shaped as a hollow cylinder engages in the annular or hollow cylindrical outer-conductor groove 119 of the socket 100 without making any other contact. It is apparent from
Between the outside end face 125 on the plug-facing limiting end of the coupler outer-conductor housing 115 and the stop shoulder 221 of the ledge 219 projecting radially outwards is inserted an additional seal 220, in particular a sealing ring or an O-ring, which is compressed between the end face 125 of the coupler outer-conductor housing 115 and the outside-lying annular ledge 219 of the plug in order to ensure that the connector is sealed to the required degree against environmental conditions.
A first variant of the solution according to the invention is now described and illustrated with reference to
The solution according to the invention referring to the axial section shown in
Unlike the prior art, however, a radial signal path is now provided separately from the mechanically acting axial stop limit, for which purpose the coupler 100, for example, is provided with a socket outer-conductor contact (or a contact acting as a socket) and the plug 200 interacting therewith is provided with a pin outer-conductor contact (i.e. at least one pin-shaped or sleeve-shaped outer-conductor contact), via which said radial signal path can be created. In other words, the electrical signal path hence runs via the (pin) coupler outer-conductor contact-making section 121, which is annular or hollow cylindrical in shape and lies inside the sleeve-shaped or cylindrical plug outer conductor 213 (socket outer-conductor contact), and which is encircled thereby, wherein the coupler outer-conductor contact-making section 121 is provided with a contact-making area 121a protruding radially outwards. This contact-making area 121a preferably lies at least near the unattached end of the coupler outer-conductor contact-making section 121, i.e. at least near or adjacent to the front face 123, which limits the coupler outer-conductor contact-making section 121 in the direction of the plug 200. The contact-making areas 121a are here embodied in the form of ridges protruding radially outwards, which project beyond the adjacent surface sections that face radially outwards of the outer conductor 113, i.e. coupler outer-conductor contact-making sections 121.
Again in this case, in a preferred variant, the coupler outer-conductor contact-making section 121 is divided by a multiplicity of slits 121b, which are mutually spaced in the circumferential direction of the coupler outer-conductor contact-making section 121 and preferably run in the axial direction, into a multiplicity of outer-conductor spring-loaded tabs 121c spaced in the circumferential direction, which are held pressed against the cylindrical inside wall 213a of the plug outer conductor 213 with an initial spring tension (this principle is also illustrated and explained in more detail below in a further discussion with reference to
In this embodiment shown in
Since the current on the coupler outer conductor 113 only flows over the inside wall 113a, this also results in only the initial spring-tension forces between the coupler outer-conductor contact tabs 121c and the inside wall 213a of the plug outer conductor 213 being crucial to signal transmission and no longer the axial contact pressures between the two mechanical stops acting in the axial direction, which are formed by the groove floor 119a of the coupler outer conductor 113 and the front face 231 of the plug outer conductor 213.
The embodiment shown in
In this case, the insulator 233 and the front face of the contact tabs 121c of the coupler outer-conductor contact section 121 is formed and/or shaped so that, on inducing the torque via the coupling nut 223, the induced axial forces between the annular shoulder 217 and the insulator 233, which is annular, for example, exert forces on the front face 123 on the contact tabs 121c, which help to increase the outwards-directed radial forces on the contact tabs 121c, and thereby the contact sections 121a on the contact tabs 121c press even more strongly in a radial direction against the inside wall 213a of the outer conductor 213 of the plug 200 and thereby further improve the electrical signal path if necessary.
In this embodiment, said insulator or insulator ring 233 is preferably permanently fixed to the coupler 100 (which is indicated by the fact that the cylindrical lip 233a is clamped against the inside wall of the plug outer conductor 213), so that a coupler such as that shown in
A variant of
The embodiment shown in
In addition in this embodiment, an insulating body, for example in the form of an insulating ring 233, is also provided, which is provided between the downwards-facing front faces 123 of the coupler outer-conductor contact section 121 and the corresponding annular stop shoulder 217 of the plug outer conductor 213, for example by suitable design, is also held at least by a friction fit on the outer-conductor support sections 121d protruding in an axial direction. When the coupling nut is tightened, the leading front faces 123 of the coupler outer-conductor contact-making section 121 hence run up against the corresponding plug outer-conductor stop 217, via the intermediary of said insulator 233, so that corresponding axial pressures, induced via the coupling nut, act here. Once again, the tension between the two outer conductors of the connectors 100 and 200 acting in the axial direction is hereby separated from the radial signal path across said contact sections 121a of the contact tabs 121c. In other words, the radio frequency signal path always runs over the conducting surfaces facing the interior I (where the interior I is that space in which the inner conductors 101 and 201 of the connectors are also present). In other words, the electrical connection is made along the RF signal path from the inside walls 113a in contact with the interior I, across the surface, which bounds the interior I, of the inside wall of the radial contact-making arrangement and from there to the inside wall 213a of the nearest connector 200, from where the RF signal path then continues e.g. to an outer conductor of a coaxial cable that can be connected to the connector 200. The axial stop acting between the groove floor 119a of the outer conductor 113 and the annular front face 231 of the other outer conductor 213 hence lies removed and/or shielded from the interior I, i.e. separate therefrom. In other words, the RF signal path spreading only over the electrically conducting surfaces bounding the interior I does not run via the axial stop, and therefore this axial stop is separate from the RF signal path.
In the embodiment shown in
A further modified embodiment shown in
In the embodiment shown in
Here, the contact tabs 121c are preferably provided in the end region of the coupler outer-conductor contact section 121, but can also be provided at a position removed from this front face 123.
The embodiment shown in
In addition, the radio frequency signal path HF-S running over the inside walls 113a and 213a of the couplers to be connected is sketched in
The embodiment shown in
In this case, even the axial pressures between coupler and plug can act between the radial front face 231 of the plug and the groove floor 119a of the coupler 100 without there being an insulator, e.g. plastic, interposed here. This is because, despite galvanic contact, the RF signals and RF currents flow over the inside wall 113a, so that only the purely mechanical pressures act in the axial direction, and only the radial signal path between the outer-conductor contact section 241 plus the outer-conductor contact tabs 241 and the coupler outer conductor 113 is crucial to current transmission and signal transmission. In this embodiment, the coupler outer-conductor contact section 121 likewise again has a shortened design in an axial direction, in a similar manner to the embodiment of
A plurality of cable connections are provided between the two according to the prior art.
Alternatively, it is now possible to provide, for example on the underside of the antenna housing, the coupler 100 according to the invention that was explained using the aforementioned embodiments, with it being possible to attach, on the corresponding upper side 13a of the electrical/electronic device 13 to be attached, the conventional plugs 200 that interact therewith or the couplers 100 and plugs 200 that are modified compared with the prior art and were illustrated, for example, using
It would also be possible in this respect to implement, for example, the one connector as a dual plug or as a dual coupler, which like an adapter piece (intermediate connector) has a plane of symmetry running perpendicular to its axial direction. Such an intermediate connector could then, if it were made in the form of a symmetrical intermediate connector, be interconnected between two coupler connectors as an intermediate connector. The inverse design would be equally possible, if the intermediate connector were designed as a dual coupler, which would then interact with a corresponding mating part (plug) at its two opposite connecting parts.
The connectors used as part of the invention can serve generally as connectors for cable connections, or else also as coaxial cable connections in those cases in which, for example, connectors designed as couplers or plugs are permanently fixed to a housing of an electrical/electronic device. Hence a connector according to the invention can also be integrated well in a device, for instance in an antenna, an antenna housing, an amplifier, a filter etc., and therefore a device equipped with such a connector can be electrically connected without difficulty to a standardised or commercial connector interacting with this device. Here, the connector connected to the device can, according to the electrical requirements of the device and the signal path provided thereby, also be equipped differently from standardised connectors, i.e. be designed so that only the key electrical values required for the device concerned need to be met, which applies, for instance, to an operating frequency range to be transmitted, environmental rating requirements, number of mating cycles etc.
The invention has been explained with reference to connectors for which either a pin contact or a socket contact is designed as the inner conductor. The invention can equally be applied, however, to connectors for which the inner conductor to be coupled has an hermaphroditic contact, which hence can be designated neither a pin contact nor a socket contact. Preferably, however, inner-conductor contact is made with a radial contact path.
For the connectors mentioned, it is immaterial to the invention whether the connector provided with a socket outer-conductor contact has a pin contact or a socket contact as the inner conductor. Likewise, it is immaterial whether the connector provided with a pin outer-conductor contact (i.e. in the form of a hollow-cylinder outer conductor where contact is made on the outer surface) is equipped with an inner conductor that is socket shaped or pin shaped. It is likewise immaterial on which of the two connectors a coupling nut is provided, which interacts with a matching external thread of the other connector.
Number | Date | Country | Kind |
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10 2008 034 583.0 | Jul 2008 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2009/004987 | 7/9/2009 | WO | 00 | 1/21/2011 |