EP2569828B1 - Coaxial high frequency connector - Google Patents

Description

The present invention is in the field of coaxial RF connectors, called RF connectors.

Coaxial RF links are essential in the transmission of high frequency signals and are often used for the connection of two devices, e.g. an antenna with a coaxial cable used. Printed circuits are ubiquitous in the field of RF front ends of modern communication systems. With the introduction of solid-state power amplifiers (SSPA), such circuits have also become attractive in the area of high-power transmitters on board satellites. Previously, this task was done by Traveling Wave Tube Amplifier (TWTA), which also required the conventional bulky waveguide technology. One way to power such circuits is to use coaxial cables and coaxial connectors. To date, the use of so-called TNC connectors has been required because the smaller SMA (Sub Miniature A) connectors were not suitable for high power transmission. The use of SMA connectors has been limited to the low voltage range up to now. Nevertheless, it would be an advantage if SMA connectors could be used for higher performance in aerospace, because they have less weight and smaller dimensions. A disadvantage, however, is that today's conventional SMA connectors have significant limitations on the maximum possible transmission performance due to their internal structure. For safety reasons, TNC connectors are still used today as soon as the transmission power exceeds a few watts. The higher weight and the larger dimensions are accepted.

SMA connectors are primarily used in applications ranging from 1 GHz to 26.5 GHz. Embodiments up to 40 GHZ are known. As a plug As a rule, embodiments with a screwed union nut and as a socket those with an external thread and regardless of the configuration of the inner conductor as a pin or as a sliding over the pin sleeve. The connector parts are referred to as SMA connector and SMA connector. Compared to other high-frequency connectors, SMA connectors are comparatively small. Today's SMA connectors are precision connectors for microwave applications, which are characterized by high mechanical strength, long life, reliability and low VSWR.

DE 102004 033567 discloses a connector according to the preamble of claim 1.

An object of the invention is to show an improved SMA connector which is suitable for use in aerospace and which avoids the disadvantages of the connectors known from the prior art.

This object is solved by the features of the independent protection claim.

The connector according to the invention in one embodiment is a threaded connector having a first (male) and a second (female) connector part. The first and the second connector part can be operatively connected to each other by a union nut. The union nut is usually arranged on the plug side. The connector of the invention, also referred to as a Power Sub-Miniature Connector (PSM), is not directly compatible with conventional SMA connectors. Although the external dimensions and weight are approximately the same, the internal connectors have a different construction which allows transmission of much higher power. If required, however, conventional SMA and PSM connectors according to the invention can be operatively connected to one another via an adapter. The PSM connectors according to the invention are largely "gap-free" in the interior but nevertheless constructed in such a way that the connector can vent when used in outer space. Conventional SMA connectors have an array of radially extending gaps that arise when used in space detrimental but not significant in conventional terrestrial applications.

The connector parts of the inventive PSM connector generally each have a sleeve-shaped housing, which is arranged outside and forms an outer conductor. In the interior of the housing, an insulator is arranged, e.g. is pressed into the housing or otherwise secured in this. The insulator has a central opening, which serves to receive a pin-shaped contact element (contact), which serves as an inner conductor. The pin-shaped contact element is also pressed into the insulator and is supported on this via a shoulder. Other configurations and types of attachment are possible.

The limitation in power transfer in SMA connectors is due, inter alia, to an inadequate arrangement and design of gaps inside and between the connector parts. Due to the inventive design of the inner life of the connector, the transmission capacity is significantly increased with the same size. Alternatively, it is possible to reduce the size at the same power compared to conventional connectors. When used in space, the problem of conventional connectors with the unfavorable arrangement of columns is exacerbated because the air contained in the columns no longer exists due to the prevailing vacuum, or escapes uncontrollably. Problems that can occur are the so-called multipactor phenomenon or the corona discharge, which can also occur with other waveguides. The unfavorable arrangement of the columns also has a negative effect on the load capacity and heat exchange capability.

For a sufficient heat dissipation is a dielectric with sufficient thermal conductivity of use. For example, PTFE has a thermal conductivity of 0.25 W / mK. Another factor which should be considered is the dielectric strength of the dielectric. In the case of PTFE, the breakdown voltage is between 40 and 80 kV / mm.

A critical area for the requirements of the electromagnetic compatibility of a connector (EMC requirements) represent the vent holes. In one embodiment, a total of three vent holes are provided, which are arranged and designed so that the high-frequency losses have no negative impact. Both connector parts each have a vent hole. Another vent hole is arranged in the contact area of the two connector part in the union nut. Inside, the connector parts may have channels that allow controlled venting. In one embodiment, the contact pin has an at least partially longitudinal channel, which serves the controlled vent. The longitudinal channel of each connector part is operatively connected via a labyrinth-like outwardly extending channel with an associated vent hole. Immediately radially outwardly extending channels are avoided as a rule.

The mechanically and / or electrically stressed connector parts are preferably made of one of the following metals: beryllium copper, stainless steel, bronze, titanium. The connector parts are preferably coated with one of the following coating materials: gold, nickel phosphor layer with a gold flash (Sucopro ™), copper-tin-zinc alloy (Sucoplate ^™ ).

In one embodiment, the invention relates to a coaxial connector with a socket-side and a connector-side connector part, both of which have an inner, extending in the connector longitudinal vent channel, which opens into at least one outwardly extending, seen in a longitudinal section staircase-like venting channel. Depending on the embodiment, both the socket-side and the connector-side connector part has an outwardly extending ventilation channel. In one embodiment is arranged at least one longitudinal venting channels in the interior of a contact (inner conductor of the connector parts). The staircase-like venting channel may be formed by an insulator of a connector part and an insulator of a cable. In the operatively connected state can be formed between the connector parts seen in longitudinal section substantially diagonally extending vent channel. The diagonal venting channel may be formed by the insulators of the connector parts. In general, the ventilation channels are designed rotationally symmetrical. Outwardly, the at least one venting duct usually opens into a vent opening. In one embodiment, the connector parts are screwed together by a plug-side cap nut.

Fig. 1

Einen Längsschnitt durch einen konventionellen SMA-Verbinder (Stand der Technik);

Fig. 2

Eine Draufsicht eines erfindungsgemässen PSM-Verbinders;

Fig. 3

Einen Längsschnitt durch den Verbinder gemäss Figur 2 entlang der Schnittlinie AA;

Fig. 4

Einen erfindungsgemässen Verbinder in einer Schnittdarstellung von schräg vorne und oben mit wirkverbundenen Verbinderteilen;

Fig. 5

Einen erfindungsgemässen Verbinder in einer Draufsicht mit nicht wirkverbundenen Verbinderteilen;

Fig. 6

Einen Längsschnitt durch den Verbinder gemäss Figur 5 entlang der Schnittlinie BB;

Fig. 7

Detail C aus Figur 6;

Fig. 8

Detail D aus Figur 6.

Based on the following figures, embodiments of the new connector will be explained in more detail. Show it

Fig. 1

A longitudinal section through a conventional SMA connector (prior art);

Fig. 2

A plan view of a PSM connector according to the invention;

Fig. 3

A longitudinal section through the connector according to FIG. 2 along the section line AA;

Fig. 4

A novel connector in a sectional view obliquely from the front and top with operatively connected connector parts;

Fig. 5

A connector according to the invention in a plan view with non-operatively connected connector parts;

Fig. 6

A longitudinal section through the connector according to FIG. 5 along the section line BB;

Fig. 7

Detail C off FIG. 6 ;

Fig. 8

Detail D off FIG. 6 ,

Unless otherwise stated, the same reference numerals are used in the figures for corresponding parts.

FIG. 1 shows for comparison purposes a sectional view (longitudinal section) through a conventional SMA connector 100 (prior art). The connector 100 has a socket part 101 and a plug part 102, which are screwed together via a union nut 103. The socket part 101 has, viewed from outside to inside, an outer housing 104, which surrounds a first insulator 106. In the first insulator 106, a first contact 108 is arranged, which serves on one side for receiving a first inner conductor 112 of a first cable 110. The plug part 102 has a second housing 105, in which a second insulator 107 is arranged, which surrounds a second contact 109. The second contact 109 is used on the outside for receiving a second inner conductor 113 of a second cable 111. In the operatively connected state (as shown), the second contact 109 is inserted into the sleeve-shaped in the region of the inner end first contact 108. It can be seen that there are a number of closed, comparatively large and radially extending cavities and gaps 114 in the interior of the connector 100. These are arranged so that a meaningful venting is not possible. Furthermore, they have a negative effect on the properties of the connector in space.

FIG. 2 shows a PSM connector 1 according to the invention in a plan view. In FIG. 3 is the PSM connector 1 according to FIG. 2 in a sectional view (longitudinal section) along the section line AA shown.

The inventive coaxial connector (PSM connector) 1 has a socket part 2 and a plug part 3, which are screwed together via a union nut 4 in the operatively connected state (as shown). The socket part 2 has a first housing 5, which serves as an outer conductor. In the first housing 5, a first insulator 7 is inserted from the front end. In this, a first contact 9 is inserted from the inside, which is supported here via a shoulder on the insulator 7 and serves as an inner conductor for signal transmission. In the region of the rear end, the first contact 9 is designed so that it can be operatively connected during assembly with a first inner conductor 13 of a first cable 15. To improve the properties, a first ferrule 11 is used in the embodiment shown, which receives the inner conductor 13 at the rear end and is inserted into the first contact 9 at the front end. The ferrule 11 serves for improved transmission of signals between the first inner conductor 13 and the connector-side connector part 3.

FIG. 4 shows the connector parts 2, 3 in operatively connected state obliquely from above. A front portion of the connector 1 is shown cut away at an angle of 90 °, so that the inner life is better visible.

The plug-side connector part 3 has, viewed from the outside inwards, a second housing 6, which serves as an outer conductor. In the second housing 6, a second insulator 8 is inserted from the front side. The first and the second insulator 7, 8 are usually made of plastic, such as PTFE and are pressed from the front end into the housing 5, 6 of the connector parts 2, 3 and anchored so. Other types of fastening are possible. In the second insulator 8, a second contact 10 is pressed from the front side. Of the second contact 10 is in the embodiment shown at the front end sleeve-shaped and with spring tongues 29 (see. FIG. 6 ) so that it cooperates in operatively connected state with the pin-shaped at its front end and inwardly offset first contact 9 of the first connector part 2. At the rear end of the second contact 10 is configured so that it can be operatively connected to a second inner conductor 14 of a second cable 16. To improve the properties, a second ferrule 12 is used in the embodiment shown, which receives the second inner conductor 14 at the rear end and is inserted into the second contact 10 at the front end. The first and the second housing 5, 6 of the connector parts 2, 3 have at their rear end depending on a flange 21, 22 for connecting an outer conductor 17, 18 of the first, respectively the second cable 15, 16. The outer conductor 17, 18 are usually fixed to the flanges by soldering electrically conductive and mechanically stable.

The housing 5 of the female part 2 has an external thread 30, which, as in the Figures 3 and 4 shown, with an internal thread 31 of the union nut 4 is operatively connected. The union nut 4 is rotatable relative to the housing 6 of the plug part 3 and arranged displaceably in the axial direction (x-direction). An arranged on the plug-side housing 6 snap ring 32 engages in an internal groove 33 of the nut 4 and thus limits the axial displacement of the nut 4 relative to the plug-side housing 6. In the operatively connected state (see. Figures 3 and 4 ), the housing 5, 6 of the connector parts 2, 3 via the union nut 4 at the end along a first and a second annular contact surface 34, 35 are pressed together. At least one of the contact surfaces has a groove 36, which ensure the venting through the third vent passage 28. The union nut 4 has an internal, annular venting channel 37, which opens here into two radially outwardly extending, diametrically opposed vent openings 38. The vents 38 serve for venting of the third vent channel 28 and the inner of the union nut. 4

The signal-conducting inner connector parts are preferably gold-plated. By the likewise gold-plated ferrules 11, 12 can be ensured that in the interior of the connector 1 results in an optimal Konnektierung. The ferrules 11, 12 are usually firmly soldered to the inner conductors 13, 14 of the cables 15, 16.

In FIG. 6 a PSM connector 1 according to the invention is shown, which consists of a socket-side first and a connector-side second connector part 2, 3. The PSM connector 1 has substantially the same dimensions as a conventional SMA connector of the prior art. Some important dimensions of this embodiment are indicated in the drawing by double arrows (unit: mm). One of the major differences between the connectors known from the prior art and the PSM connector 1 shown here is that it deliberately avoids harmful air gaps. If columns are unavoidable, they are arranged according to the inventive concept so that an optimal transmission capacity is achieved.

As in the Figures 3 . 4 . 6 and the details C and D according to the FIGS. 7 and 8 can be seen, the first and the second contact 9, 10 each have a longitudinal venting channel 24, 25. These open in each case in their rear area in a labyrinthine first, resp. second outwardly extending vent channel 26, 27. The outwardly extending gap-like venting channels 26, 27 extend in several stages stepwise outward and open at its outer end in vent holes 23. They are doing by the mutually correspondingly offset insulators 19, 20 of the cable 15th , 16 and the insulators 7, 8 of the connector 2, 3, and the housing 5, 6 are formed.

In the operatively connected state (cf. Figures 3 and 4 ) formed by the insulators 7, 8 of the connector parts 2, 3, a third gap-shaped vent channel 28, viewed in longitudinal section substantially diagonally, ie at an angle α to the connector longitudinal axis (x-axis) to the outside and opens at the outer end in the vent opening 23 , The third Venting channel 28 is also operatively connected to the longitudinal venting channels 24,25. In the example according to FIG. 6 the angle α of the ventilation channel is approximately 21 °. The third vent channel 28 is formed by two conical end faces 39, 40 of the first and second insulators 7, 8 of the connector parts 2, 3. The end surfaces 39, 40 are designed so that they give an annular third vent passage 28 with a constant thickness. The stated mass can vary within a certain tolerance range, provided that the functionality is not adversely affected. <b> LIST OF REFERENCE SIGNS </ b> 1 Connector (PSM connector) 22 Second flange (second housing) 2 Socket (socket-side, respectively first connector part) 23 vent holes 3 Plug (connector side, respectively second connector part) 24 First longitudinal venting duct 4 Cap sleeve (union nut) 25 Second longitudinal venting channel 5 Housing of the female part (first housing) 26 Outwardly extending first venting channel 6 Housing of the plug part (second housing) 27 Outwardly extending second vent channel 7 First insulator (female part) 8th Second insulator (plug part) 28 Outward running third 9 First contact (socket side) vent channel 10 Second contact (connector side) 29 spring tongues 11 First ferrule (female part) 30 external thread 12 Second ferrule (plug part) 31 inner thread 13 Inner conductor first cable 32 snap ring 14 Inner conductor second cable 33 groove 15 First cable (socket side) 34 First contact surface (socket side) 16 Second cable (connector side) 17 Outer conductor first cable 35 Second contact surface (plug side) 18 Outer conductor second cable 19 Isolator first cable 36 groove 20 Isolator second cable 37 Annular venting channel 21 First flange (first housing) 38 Outer vent 39 First conical end surface 107 Second insulator (plug part) 40 Second conical end surface 108 First contact (socket side) 100 SMA connectors 109 Second contact (connector side) 101 Buchsenteil6 110 First cable 102 plug part 111 Second cable 103 Nut 112 First inner conductor (first cable) 104 First housing (female part) 113 Second inner conductor (second cable) 105 Second housing (plug part) 106 First insulator (female part) 114 Cavity (gap)

Claims (9)

1. Connector (1) comprising a female and a male connector part (2, 3), the two connector parts (2, 3) each having an internal ventilation duct (24, 25) extending in the connector longitudinal direction (x), characterised in that the connector is a coaxial connector and in that the ventilation duct (24, 25) opens into at least one outwardly extending ventilation duct (26, 27), which is stepped when viewed in longitudinal section.
2. Coaxial connector (1) according to claim 1, characterised in that both the female and the male connector parts (2, 3) have an outwardly extending ventilation duct (26, 27).
3. Coaxial connector (1) according to any of the preceding claims, characterised in that the longitudinal ventilation ducts (24, 25) are arranged in the interior of a contact (9, 10).
4. Coaxial connector (1) according to any of the preceding claims, characterised in that the stepped ventilation duct (26, 27) is formed by an insulator (7, 8) of a connector part (2, 3) and an insulator (19, 20) of a cable (15, 16).
5. Coaxial connector (1) according to any of the preceding claims, characterised in that, when operatively connected, a substantially diagonal ventilation duct (28) is arranged between the connector parts (2, 3) when viewed in longitudinal section.
6. Coaxial connector (1) according to claim 5, characterised in that the diagonal ventilation duct (28) is formed by the insulators (7, 8) of the connector parts (2, 3).
7. Coaxial connector (1) according to any of the preceding claims, characterised in that the at least one ventilation duct (26, 27, 28) is designed to be rotationally symmetrical.
8. Coaxial connector (1) according to any of the preceding claims, characterised in that the at least one ventilation duct (26, 27, 28) opens into a ventilation opening (23, 38).
9. Coaxial connector (1) according to any of the preceding claims, characterised in that the connector parts (2, 3) can be screwed together by means of a male union nut (4).

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