EP0773602A2 - Plug connection system - Google Patents

Abstract

The invention relates to a plug device system which is designed for high voltage in the medium voltage range and for underlying voltages, in particular for connecting continuous cables in railway trains, and which is formed by at least two complementary plug devices (2, 3) for producing at least one conductor connection, the plug devices (2, 3) inner conductor parts (6, 7, 10, 11) and outer housing parts (8, 9), and wherein the conductor parts (6, 7, 10, 11) in the assembled state of the connector system (1) without gaps and are tightly covered with insulating material relative to the housing parts (8, 9). According to a further aspect of the invention, live conductor contact parts (6, 7) are equipped with insulating material in such a way that when the plug-in device system (1) is disconnected but ready to be plugged in, both plug-in devices (2, 3) prevent people from touching live parts is. According to a third aspect, the conductor contact part (6, 7) is soft in the pressing area and hard in the plug area. <IMAGE>

Description

The invention relates to a connector system which is designed for high voltage in the medium voltage range (1 kV to 30 kV), in particular in the lower medium voltage range. In numerical terms, the latter range lies between 1 kV and 6 kV, in particular between 2 kV and 4 kV; a typical voltage for this range is approximately 3 kV. The connector system can also be designed for voltages below it (e.g. in the range of 110 V to 1 kV).

The connector system is particularly suitable for use in the field of railway technology. The modern development in passenger trains and in some cases also in freight trains is tending to replace curled trains with railcars. Here, all or at least a considerable part of the wagons of a train are equipped with drive devices, such as control units, converters and drive motors. In such modern multiple units, the individual wagons must be electrically connected to one another by one or more cables in the voltage range mentioned above. The cables are used for energy transmission (typically 3 kV alternating current at 16 2/3 Hz, 50 Hz or variable frequency with 100 A to 1200 A). In order to be able to separate the individual wagons of a multiple unit, the electrical connection must be detachable. The invention provides a suitable connector system.

Plug-in device systems for connecting continuous cables in railroad trains are known in the prior art, for example for supplying the wagons of a conventional train with heating current. The known systems repeatedly lead to failures due to short circuits in railway operations. Occasionally accidents occur to the operating personnel due to electric shock.

A connector system for voltages of e.g. 25 kV for use in railway trains is known from DE 195 09 012 A1.

The invention has set itself the goal of providing a connector system with greater operational safety and accident safety.

The invention solves the first aspect of this problem (operational safety) with the plug-in device system according to claim 1 and the second aspect (accident safety) with the plug-in device system according to claim 10. It is particularly advantageous to combine both aspects in one plug-in device system. Finally, a third aspect of the invention according to claim 15 is directed to a special design of a conductor contact part of a plug-in device, which increases the stability against frequent plugging and unplugging (as occurs in railway operation).

Of course, the plug-in device system according to the invention is also outstandingly suitable for other (for example stationary) applications, for example in industry, in workshops or in households.

In order to arrive at the first aspect of the solution with the aim of avoiding short circuits, the following had to be recognized first: with conventional plug-in device systems, inner conductor parts are generally open, at least insofar as they are designed for the lower medium-voltage range or the area underneath, with respect to outer ones Ground parts of the housing, at least in places, are only insulated by an air layer, because this is sufficient for insulation at such voltages. It was recognized that condensation films are responsible for the occurrence of short circuits in such connector systems, since the conductor and housing parts, which are insulated from one another by air, can generally are connected to each other by a condensation film, which has sufficient conductivity for a current flow due to dissolved ions. This current flow would be harmless in itself because of its low current intensity, but it leads to drying of the condensed water film at the thinnest point. If the current flow is interrupted, an arc can form, which ultimately leads to a full breakdown (i.e. short circuit). A watertight encapsulation of the plug would not be an optimal solution, as water gradually diffuses into the cavities over time, which can then form a condensate film when the temperature drops. Sudden drops in temperature of a relatively large extent (e.g. 30 ° C) often occur in railway vehicles, for example when leaving a heated vehicle shed in winter.

• durch wenigstens zwei komplementäre Steckvorrichtungen zum Herstellen wenigstens einer Leiterverbindung gebildet wird,
• wobei die Steckvorrichtungen innere Leiterteile sowie äußere Gehäuseteile aufweisen, und
• wobei die Leiterteile im zusammengesteckten Zustand des Steckvorrichtungs-Systems lückenlos und dicht mit isolierendem Material gegenüber den Gehäuseteilen abgedeckt sind (Anspruch 1).

Die Gehäuseteile liegen i.a. auf Masse.Based on these findings, the invention provides, according to the first aspect, a plug-in device system which is designed for high voltage in the medium-voltage range, in particular in the lower medium-voltage range, and for voltages in the area below, in particular for connecting continuous cables in railway trains, and

• is formed by at least two complementary plug devices for establishing at least one conductor connection,
• wherein the plug devices have inner conductor parts and outer housing parts, and
• wherein the conductor parts are completely and tightly covered with insulating material relative to the housing parts in the assembled state of the plug device system (claim 1).

The housing parts are generally grounded.

Due to the gap-free and tight cover made of insulating material, no current path from the tensioned inner conductor parts to the earthed outer housing parts can form in the event of condensate precipitation. Arcs with short circuits due to condensate films can therefore no longer occur.

In the following, "outwards" means the radial direction leading radially outwards from the cable center. "Inward" indicates the opposite radial direction. The "longitudinal direction" is the direction in which the cable core runs. The "end face" is the side of the plug devices with which they are plugged together. The same applies to similar terms such as "outer", "outer", etc.

In principle, in the case of the plug devices of a plug device system, the space between the conductor parts and the housing could be completely filled with insulating material, for example poured out. Such connectors have relatively high manufacturing costs. In addition, considerable thermal stresses can occur with them, which can shorten their lifespan. Finally, such connectors are generally irreparable and must be thrown away as a whole in the event of damage. Therefore, the plug device system is preferred one or more cavities present between the conductor parts and the housing (claim 2). As stated above, the air present in the cavities is sufficient for insulation, at least in the lower region of the medium voltage and below, so that additional solid insulation would not be necessary. The cover according to the invention with insulating material ensures that no current paths can form between the conductor parts and housing parts in the condensate which is deposited.

A particularly advantageous possibility of realizing the covering of conductor parts consists in using a shrink film, in particular in the form of a shrink tube (claim 3). The shrink tube is long enough to cover the gap completely, so that it also covers adjacent conductor insulation in addition to the exposed conductor part (e.g. the crimping area of a conductor contact piece). During manufacture, it is pushed onto the exposed conductor part with sufficient overlap of the neighboring conductor insulation and e.g. caused by heat to shrink. This results in a complete and tight cover with insulating material, which interrupts the surface current paths between the conductor parts and the housing.

Another starting point for surface current paths is conventionally found in the plug-in area, that is, where the conductor parts of the plug-in devices are plugged together for the purpose of switching contacts. To exclude such current paths, a labyrinth seal and / or a plug seal is advantageously provided in this area (claim 4). These are sealing elements which are designed such that they cover and seal the conductor parts with respect to the housing parts when the plug devices are plugged together in the plug region.

The term "labyrinth seal" is understood to mean one with which gaps can remain, but which run like a labyrinth (i.e. around several edges). In relation to the distance, this results in relatively long creepage distances. “Plug-in seal” is understood to mean one that effects a complete seal without a remaining gap.

In principle, the plug-in seal can be implemented by one or more sealing surfaces which are pressed onto one another in the plug-in direction. However, the plug seal advantageously comprises two sealing elements which overlap in the plug direction (claim 5). If, for example, one of the sealing elements has a conical shape, so that its circumference at the line of contact with the other sealing element increases when plugged together, this results in a sealing surface in which the sealing elements are pressed onto one another essentially in the radial direction. Such a seal is particularly robust.

In order to enable simple plugging and unplugging of the plug devices, the plug seal advantageously comprises a flexible and a hard sealing element (claim 6). The flexible sealing element can for example be made of silicone rubber, the hard one made of polyamide. The hard sealing element advantageously has the shape of an outer cone which, when plugged together, penetrates into the resilient sealing element in the form of a cylinder jacket and expands in the process. The elastic restoring force of the cylinder jacket in the radial direction causes the sealing effect.

With these two measures, a continuous and tight covering of the conductor parts can be realized in the plugged-in state of the plug device system, so that then no surface current paths to the housing are possible.

In the non-assembled state, however, there are generally current paths between the (then exposed) mating surfaces of the conductor parts and the housing. In order to avoid short-circuits even when not connected, a labyrinth insulation is advantageously implemented in the plug-in area of the conductor parts, which requires at least a relatively long path over insulating surfaces for a surface current path from conductor parts to the housing (claim 7). This greatly impedes current flow and arcing.

The labyrinth insulation is advantageously realized in that one plug device has an inner contact element, which is seated in an insulating sleeve, and the other plug device has a complementary outer contact element, which is coated on the outside with insulating material (claim 8). When plugged together, the outer contact element penetrates into the space between the inner contact element and the insulating sleeve. The contact surfaces are therefore on the outside of the inner contact element and the inside of the outer contact element. In order to get from the conductor to the housing, the current must therefore take the relatively long way over the inside of the insulating bush in the plug device with the inner contact element, and the relatively long way over the outside covered with insulating material in the plug device with the outer contact element.

Labyrinth insulation is even more effective if the outer contact element additionally has an attachment made of insulating material on the front side (claim 9). The current must then also make its way over the insulating attachment on its way from the contact surface of the outer contact element.

The surfaces of the labyrinth insulation are advantageously at least partially water-repellent, e.g. by the insulating parts (sleeves, attachments, etc.) made of water-repellent material or coated with such. This leads to pearl formation and additionally complicates the fact that a coherent film of water can form.

The second aspect of the invention relates to the risk of accidents in known plug-in device systems. In order to avoid electric shocks in known plug-in device systems, the voltage must generally be switched off at least on one of the two plug-in devices. If, in the prior art, the corresponding plug device is inadvertently not switched off in the disconnected state, operating personnel and possibly travelers may experience serious accidents due to electric shock.

To solve this problem, the invention according to claim 10 provides a connector system in which live conductor contact parts are equipped with insulating material so that in the disconnected but ready-to-plug-in state of the connector system, contact with live parts by both connectors is excluded. The emphasis is on the fact that both plug-in devices — and not just one of the two, as is known in the prior art — are designed to be safe to touch. This is important for all applications in which a separate cable can carry voltage from both sides to the separation point (e.g. on railways, on devices that can act as a voltage source when disconnected, such as machines that continue to rotate or devices with internal voltage storage devices due to inertia , such as capacitors). “Ready to plug in” means that the plug devices are open at the end, that is to say not covered by a housing cover or the like are (because there is a trivial protection against contact through the housing cover). Of course, the connector system is safe to touch even when plugged together.

The contact protection is preferably based on the fact that the live parts of both plug devices are arranged behind sufficiently narrow gaps or passages of the insulating material (claim 11). When plugging together, the contact elements of the complementary plug device can enter the narrow gaps or passages and make electrical contact further inside. The gaps or passageways are so narrow that it is not possible for an operator to touch the lower, live parts with his finger or another part of the body.

The live parts are preferably covered on the end face with insulating material to achieve protection against contact (claim 12).

In order to prevent an inner contact element from being freely accessible from the outside and to be touched with it, it is advantageously seated in an insulating sleeve (claim 13), this measure - as stated above - also being advantageous for providing a labyrinth insulation. The complementary outer contact element can be in the narrow space, e.g. enter a narrow annular gap between the inner contact element and the insulating sleeve and make the contact. An operator's finger, however, does not fit into the narrow annular gap.

In order to ensure protection against contact in the plug-in device with the outer contact element, the latter is advantageously of hollow cylindrical design and has in its interior a central, end-face body or mandrel made of insulating material, the complementary inner one Contact element of the other plug device in the assembled state receives the central mandrel (claim 14). The central mandrel has the effect that even with the outer contact element only a narrow annular space remains, into which the inner contact element can enter and make contact, but on the other hand an operator's finger cannot penetrate.

The following third aspect of the invention relates to a particularly low-wear and, at the same time, simple design of a plug-in device system, which is therefore particularly suitable for rough railway operations. Namely, the connector system according to claim 15 has in at least one of the connectors a one-piece conductor contact part, which is connected at one end in a conventional manner to the end of the conductor of the associated cable by pressing. At the other end, it makes the electrical contact by touching the complementary conductor contact part of the other plug device. The special wear resistance is now achieved in that the conductor contact part is soft in the pressing area and hard in the plug-in area (where the contact with the complementary conductor contact part takes place) (claim 15).

The complementary conductor contact part can also be made hard and soft in this way. This is not necessary in order to achieve freedom from wear of the actual contact area if the complementary conductor contact part is equipped, for example, with resilient contact lamellae which touch the first-mentioned (hard in the contact area) conductor contact part and establish the contact. However, in order to also avoid wear of edges, the conductor contact part equipped with contact lamellae is advantageously made correspondingly hard and soft in such a case. Incidentally, "hard" and "soft" are to be understood here as relative terms, ie in the sense of "harder" and "softer". A soft in the pressing area and in Mating area hard formation of a one-piece conductor contact part is incidentally not only advantageous in the voltage ranges specified at the outset, but generally in the case of electrical connectors.

The hard formation in the plug-in area of the conductor contact part is advantageously achieved by heat treatment, e.g. Annealing, hardening, tempering, aging and / or hardening achieved (claim 16). It can be a heat treatment that only has an effect on the surface that serves to establish contact or - alternatively - on the entire workpiece structure (including the interior of the workpiece) in the plug-in area. The conductor contact part is made in particular from a metal of high conductivity, in particular from copper or a copper alloy, and is advantageously coated with a noble metal (e.g. silver or gold) in the area of the contact surface.

Alternatively, the conductor contact part can be made in one piece from at least two metal parts of different hardness, e.g. from an aluminum and a copper part, a brass and a copper part or a bronze and a copper part (claim 17). The two parts can be made in one piece by friction welding (one part is pressed against the other, stationary part so that the resulting frictional heat leads to the welding). The softer side forms the pressing area, the harder the mating area.

The above-mentioned measures in accordance with aspects 1 to 3, taken by themselves or in any combination, implement a particularly reliable, accident-proof and wear-resistant plug-in device system which is easy to use and relatively simple, and thus in a special way to meet the high requirements of railway operations enough.

The following are some configurations that can be used advantageously in all three aspects:

Although the plug-in connection system can in principle be designed as a single pole, a two-pole design is advantageous, the housing parts being used to produce a pluggable ground connection (claim 18).

For ease of use and ease of manufacture, the inner and outer contact element and / or the contact elements and the housing parts are arranged concentrically to one another (claim 19).

Cables hanging freely between railway wagons permanently perform pendulum movements, which can lead to disruptive relative rotations of the conductor contact parts of the two plug devices at the contact point. A rotationally fixed connection between the cable and the housing can prevent such undesirable rotation. It has been recognized that a firm mechanical clamping is disadvantageous because of the heating of the cable when there is a large current flow, because the insulating cable sheath made of polyethylene expands and deforms plastically when heated. A firm mechanical clamping leads to the deformation of the cable is therefore not permanent. In order to realize a permanent protection against rotation, the introduction of the cable into the plug-in device is advantageously designed as a kind of stuffing box with a flexible pressure element (claim 20).

The resilient pressure element is advantageously a soft elastomer ring, which surrounds the outside of the cable and sits in a housing space which narrows conically in the longitudinal direction of the cable (claim 21). With the help of a pressure medium that can be adjusted in the longitudinal direction of the cable (eg a threaded ring), it is pressed into the cone and thereby presses against the cable and the inner wall of the housing in the radial direction. This soft mechanical clamping is realized even with frequent Cable heating and cooling a permanent anti-twist device.

In the general case, the plug device system is used for the detachable connection of a continuous cable and therefore consists of a single plug and a single socket. In addition, the plug device system can consist of a branch plug or a branch socket, in which two or more cables are firmly connected, and a complementary (single or branch) plug device. It is also possible that one of the connectors of the system is a special connector, e.g. a blind connector (for completing a blind connector), surge arrester connector or voltage indicator connector (claim 22). The special plugs can form a set with single plugs or sockets and with branch plugs or sockets. Surge arrester plug devices can be equipped, for example, with metal oxide pills (similar to diodes) as surge arresters. Several of these pills can be arranged in series directly on top of each other; their number defines the breakdown voltage. The voltage display can be easily implemented, for example, by a clamp lamp.

Fig. 1

einen Längsschnitt eines Steckvorrichtungs-Systems mit Buchse und Stecker in zusammengestecktem Zustand;

Fig. 2

einen Längsschnitt der Buchse aus Fig. 1 mit geschlossenem Stirndeckel;

Fig. 3

den Stecker aus Fig. 1 mit geschlossenem Stirndeckel; und

Fig. 4

einen Längsschnitt durch eine Kabeleinführung mit Verdrehsicherung;

Fig. 5

eine Verzweigungssteckvorrichtung, teils in Draufsicht, teils aufgeschnitten.

The invention will now be explained in more detail on the basis of exemplary embodiments and the attached drawing. The drawing shows:

Fig. 1

a longitudinal section of a connector system with socket and plug in the assembled state;

Fig. 2

a longitudinal section of the socket of Figure 1 with a closed end cover.

Fig. 3

the plug of Figure 1 with a closed front cover. and

Fig. 4

a longitudinal section through a cable entry with anti-rotation;

Fig. 5

a branch connector, partly in plan view, partly cut open.

The connector system 1 according to FIG. 1 is designed for high voltage in the lower medium voltage range and is used for the detachable connection of continuous cables in railway trains between individual wagons of a train. The system 1 shown is designed for 3 kV alternating current at typically 800 A to a maximum of 1200 A.

It is formed by two complementary plug devices 2, 3, namely a plug 2 and a socket 3, which are each attached to the end of high-voltage cables 4, 5. They each have a central, one-piece conductor contact part 6, 7, namely a plug contact part 6 or a socket contact part 7, as well as the conductor contact parts 6, 7 and housing parts 8, 9 surrounding the cable ends, namely a concentric arrangement around the longitudinal axis of the system 1, namely a plug contact part 6 surrounding connector housing part 8 or a housing part 9 surrounding the socket contact part 7.

The above assignment between conductor contact parts 6, 7 and housing parts 8, 9 is only exemplary: in other (not shown) embodiments, the socket contact part is assigned to the plug contact part and the plug housing part is assigned to the socket contact part.

The plug-in device system 1 provides a two-pole, concentric, high-voltage plug connection, specifically connecting the conductor contact parts 6, 7 with high voltage Conductors 10, 11 of the high-voltage cables 4, 5. In addition, the housing parts 8, 9 produce a conductive ground connection. Depending on the way in which the plug-in device system 1 is used, this can serve the following functions: i) the ground connection can be used to return the current flowing through the conductors 10, 11; ii) if the current is fed back in another way (for example via the railroad tracks or a separate cable), the ground connection - possibly together with a shielding of the high-voltage cables 4, 5 - can be used to discharge breakdown currents at a low level. Without such a derivation, relatively high voltages could arise on the shield and the housing part as a result of a breakdown. However, the low-ion derivation causes these voltages to remain in a harmless low range (eg below 40 volts) and is therefore used to ensure that they are safe to touch.

The high-voltage cables 4, 5 are constructed as follows from the inside to the outside: the inside is formed by conductors 10, 11 in the form of a rope. This is followed by an insulation jacket 12 made of insulating plastic, e.g. Polyethylene. A shield 13 follows, e.g. in the form of a wire mesh. Finally, on the outside there is a protective jacket 14 made of insulating plastic, which has no electrical function, but serves the mechanical protection and the corrosion protection of the high-voltage cable 4, 5. Cables for higher high voltages generally have a semiconducting layer on the conductor and another on the insulation jacket in order to avoid field increases. With the smaller high voltages present here, such a measure is not necessary, but can be provided as an option.

For connection to the plug device 2, 3, the conductor 10, 11 is gradually exposed in the longitudinal direction of the cable. Seen from the end of the cable, it is freed of all cover layers in a first section 15. A second section follows 16, in which the insulation jacket 12 forms the exterior. This is followed by a third section 17, in which the shield 13 is freed from the protective jacket 14 and folded back. This is followed by the undamaged cable 4, 5 with the protective jacket 14.

The plug contact part 6 or the socket contact part 7 is pressed onto the exposed section 15 of the cables 4, 5 by deformation of a press section 18. On the face side, the two pressed-on contact parts 6, 7 each have a contact head 19, 20, namely a plug contact head 19 and a socket contact head 20. The two contact heads 19, 20 are designed to be complementary to one another and engage in the plugged-in state of the plug-in device system 1, as a result of which they Effect conductor connection.

Both contact heads 19, 20 have an insulating sleeve 21, 22 on the outside, namely a plug insulating sleeve 21 and a socket insulating sleeve 22. The insulating sleeves 21, 22 are designed to be complementary to one another and engage in one another when the connector system 1 is plugged together. They are made of hard insulating plastic, e.g. Made of polyamide. The insulating sleeve 21, 22 does not extend over the pressing section 18, so that this - if no additional insulating means were provided - would be open with its conductive surface.

The inside diameter of the housing part 8, 9 is considerably larger (for example by a factor of two) than the outside diameter of the pressing section 18. Between the two, a cavity 23 remains, which is circular in cross-section. On the one hand, a spacer ring 24 made of insulating plastic is used to hold the conductor contact part 6, 7, which is arranged between the outside of the insulating sleeve 21, 22 and the inner wall of the housing part 8, 9. On the other hand, the conductor contact part 6, 7 is held indirectly by holding the cable 4, 5 in a cable bushing 39, 40, which forms part of the housing of the plug device 2, 3.

Without additional measures, in this arrangement, current paths could form between high-voltage parts and parts lying on the ground in the event of condensation, for example, Current flows from the outside of the pressing section 18 over the surfaces of the adjacent part of the insulating sleeve 21, 22 and the spacer ring 23 to the inner wall of the housing part 8, 9. Furthermore, a current path could form in the contact area, which leads from the high-voltage contact heads 19, 20 through a gap between the insulating sleeves 21, 22 to the inner wall of the housing part 8, 9. Such current paths can - as stated above - cause arcing when the condensate film dries, and thus lead to a short circuit.

To rule this out, the conductor contact parts 6, 7 and a small piece of the conductor 10, 11 exposed from the insulation jacket 12 are completely and tightly covered with insulating material with respect to the housing parts, so that conductive condensate films no longer have current paths between high-voltage parts and housing parts lying on ground can manufacture. Namely, a shrink tube 26 (for example, made of cross-linked polyethylene) is arranged over the exposed pressing section 18 and the exposed part of the conductor 10, 11, the ends of which have the protective jacket 14 on the one hand and an end flange 27 of the insulating sleeve directed towards the cable 4, 5, on the other hand 22, 23 overlaps. The end flange 27 has a bead-shaped thickening 28 on its outer edge. In the shrunk state (after heating), the shrink tube 26 hugs the insulation jacket 12, the outside of the pressing section 18 and the end flange 27 and thus forms a continuous and tight cover of the conductor contact part 6, 7 in the area of the pressing section 18 and the exposed conductor 10, 11. Die Thickening 28 prevents the shrink tube 26 from slipping off the end flange 27.

Measures are also taken in the area of the contact heads 19, 20 which effectively prevent any current paths in condensate films which could bridge a cavity 25 located in the plug-in area. On the one hand, the socket insulating sleeve 22 is provided with a deep annular groove 29 into which a complementary annular extension 30 of the plug insulating sleeve 21 engages. This creates a labyrinth seal. In addition, outside of the labyrinth seal, a plug-in seal is formed by two sealing elements 31, 32 that overlap in the plug-in direction, namely a hard sealing element 31 and an elastic sealing element 32. The hard sealing element is formed by the outer jacket of the sleeve insulating sleeve 22, which tapers slightly conically, with a decreasing diameter towards the end face. The elastic sealing element 32 is an annular elastomer part, which on its inside is complementary to the sealing element 31 (that is, it widens conically) and runs onto it when it is plugged together. The elastic sealing element 32 is expanded in the radial direction. The elastic restoring forces in the elastomer cause a pressure against the hard sealing element 31 and thus a seal.

Both measures - the labyrinth seal and the plug-in seal - on the one hand create a seal against water (e.g. splashing water) and on the other hand an electrical seal between live parts and the housing, thus preventing the occurrence of arcs and short circuits.

The contact heads 19, 20 are constructed as follows: the plug contact head 19 has an inner contact element 33 in the form of a hollow cylinder, which is formed here in an insulating sleeve spaced therefrom a part of the plug insulating sleeve 21 with the extension 30 - sits. Resilient contact lamellae 34 are arranged in an annular recess of the inner contact element 33. On the face side, the inner contact element is equipped with a likewise hollow cylindrical attachment 35 made of insulating material, which extends on the outside of the inner contact element 33 to the contact lamellae 34 and on the inside thereof up to half the depth of the inner contact element 33. The socket contact head 20 has a likewise hollow cylindrical outer contact element 36 which, when plugged together, engages over the inner contact element. The electrical contact is then mediated by pressing the contact lamella 34 against the inner wall of the outer contact element. The outer contact element 36 also has an attachment 37 on the end face made of insulating material, which is integral with the socket insulating sleeve 22. On the outside, it is completely covered with insulating material, the cover also being part of the socket insulating sleeve 22. A cylindrical mandrel 38 is inserted in the center of the outer contact element 36, the end face being almost flush with the attachment 37. It is designed such that it engages in the central cavity of the inner contact element 33 in the assembled state.

This configuration of the contact heads 19, 20 primarily has the function of excluding the contact of high-voltage parts in both plug devices - that is to say both the plug 2 and the socket 3 - in a separate and open state, and indeed the plug contact head 19 appears to the outside as the face of two concentric hollow cylinders made of insulating material; and the socket contact head 20 appears to the outside like the face of a hollow cylinder with a central mandrel, also made of insulating material. The annular gap between the hollow cylinders and their central opening or between the hollow cylinder and the mandrel are so narrow that an operator cannot touch parts carrying high voltage with one finger.

In addition, the insulating attachments 35, 37 and the insulating mandrel 38 have a guiding function, because their beveled edges bring the two contact heads 19, 20 into the correct relative position when they are plugged together. After all, they have the function of a labyrinth insulation when it is not connected. In this state, a current path in the condensate film cannot be completely ruled out due to the absence of the respectively complementary insulating sleeve 21 or 22 and the respectively complementary sealing element 31 or 32. However, the very long distances over insulating surfaces significantly reduce the risk of current flow with subsequent arcing and a short circuit. Specifically, the current at the plug contact head 19 would have to take the path via the insulating bush and at the socket contact head 20 via the attachment 37 and the insulating outer wall of the outer contact element 36.

The conductor contact parts 6, 7 are made in one piece from copper or a copper alloy. You are pressed in the pressing section 18 with such high pressures with the conductor 10, 11 that almost a cold flow occurs here. To enable this pressing, the copper is here in its usual (soft) form. In the area of the contact heads 19, 20, on the other hand, the conductor contact parts 6, 7 are hardened, specifically by means of heat treatment such as, for example, annealing. This on the one hand prevents wear on the outer contact element 36 due to the attack of the contact lamellae 34. On the other hand, the hardening serves to protect the edges of the contact heads 19, 20 insofar as there is contact between the edges of the copper parts with one another and with other parts (for example insulating parts) when plugged together. For this reason, the copper of the plug contact head 19 is also advantageously hardened, although this is not subject to attack by contact lamellae. To improve the contact, the contact heads 19, 20 are silver-plated.

The housing parts 8, 9 each comprise a cable bushing 39, 40, a hollow cylindrical housing body 41, 42 and a protective flap 43 hinged to it and spring-loaded to the closed position. 44. The parts mentioned are made of metal, e.g. Aluminum. The socket housing part 9 has a narrow annular groove 45 on the end face, into which a complementary annular plug extension 46 engages, which is integral with the plug housing part 8. The socket housing body 42 has near its front end on its inner wall an annular recess which is equipped with resilient contact blades 47. These press against the plug extension 46 from the outside and thus establish the ground connection. At its front end, the socket housing body 42 carries an annular seal 48 made of elastomer material, which is inserted in an annular groove and which, when assembled, e.g. seals against splash and rain water.

In the socket housing part 9, the articulation point of the self-closing protective flap 44 is located directly at the front end of the housing body 42. Since the plug housing part 8 can be inserted into the socket housing part 9, the articulation point here is not directly on the housing body 41, but rather on a bracket 49 attached to it, which overlaps the socket housing body 42 on the outside over a length corresponding to the insertion depth. When the plug devices 2, 3 are disconnected, the protective flaps 43, 44 close and in each case lie against the outer end edge of the housing body 41, 42, the ring seal 48 (or a corresponding ring seal (not shown) in the plug housing body 41) running therein provides a hermetic seal.

The protective flaps 43, 44 are curved outwards, so that a minimum distance from the nearest high-voltage-carrying part is maintained at each point of the protective flap 43, 44. Such minimum distances are in some countries (e.g. Italy) required for security reasons. In other (not shown) embodiments, the protective flaps are essentially flat.

The housing bodies 41, 42 each have a support surface 50 oriented parallel to the plug-in direction, on which in the assembled state the protective flap 44, 43 belonging to the other housing part 9, 8 rests with its inner edge. This prevents contamination of the inside of the protective flap.

On the outside of the plug device system 1, two pull / push lever locks 56 are arranged opposite each other, with the aid of which the plug 2 and the socket 3 can be pulled together and pressed apart (see FIG. 5).

The plug-cable bushing 39 has at its end facing the end face an end flange 51 which lies in the axial direction and has a thickening 52 on its outermost edge. When assembling the connector 2, the shield 13 is withdrawn via the end flange 51 and mechanically and electrically connected behind the thickening 52 with the aid of a clamp 53 to the cable bushing sleeve (which in turn is electrically connected to the other parts of the housing part 8). In the embodiment shown, the shield 13 is not used to conduct the reverse current, but only for the low-ion derivation of any breakdown currents. The shield 13 is therefore to be subdivided here into individual sections which are isolated from one another. For this reason, the socket housing part 9 does not have a corresponding end flange for leading out and fastening the shield 13. Rather, this remains under the protective jacket 14 without contacting the housing. In other embodiments (not shown) - in which the plug-in device system also provides a continuous ground connection for conducting the reverse current - this is also the case Socket housing part 9 equipped with a corresponding end flange.

For use on railway vehicles, for example, the socket 3 is fixedly mounted on a corner of the railway vehicle. The high-voltage cable 5 leading out of the socket 3 runs, for example, stationary on the underside of the vehicle. On the other hand, the high-voltage cable, which is firmly connected to plug 2, leads to the next vehicle in a sagging manner. In order to avoid kinking of the sagging cable 4, the plug-cable bushing sleeve 39 is inclined downward in accordance with the curve usually occupied by the cable (FIG. 4). The inclination also largely prevents twists of the cable 4 from propagating into the interior of the plug 2. So it also acts as an anti-twist device.

Towards the end of the cable, the bushing sleeve 39 tapered apart. An elastic pressure element in the form of a soft, essentially hollow cylindrical rubber ring 54 is inserted into the conical cavity formed in this way. A ring nut 55 arranged at the extreme end allows the rubber ring to be braced into the conical cavity, as a result of which a soft, wide-locking connection between the cable bushing sleeve 39 and the cable 4 is achieved in the manner of a stuffing box. This additionally prevents twists, for example due to pendulum movements of the free-hanging cable 4, from propagating into the interior of the plug 2 and leading to relative rotations of the conductor contact parts 6, 7 (FIG. 4).

In other (not shown) embodiments, the socket 3 is additionally or alternatively equipped with a curved cable bushing and / or an (additional) anti-rotation device in the manner of a stuffing box.

5 (which may be a plug or socket - the restriction to the reference numerals referring to a plug only serve for simplification), two high-voltage cables 4 are brought together in a plug-in device and firmly connected to one another. The conductor contact part 6 is here a composite part, consisting of a pressing section 6a for each cable, a contact section 6c, and a connecting bridge 6b running at right angles thereto for connecting these sections. The pressing sections 6a are each connected to the connecting bridge 6b with the aid of a blind screw 57, and the connecting bridge 6b is in turn connected to the contact section 6c with the aid of a blind screw 58. The compression sections 6a are also covered here with a shrink tube 26. The connecting bridge 6b and the adjacent part of the contact section 6c, however, are covered with molded parts 26a made of insulating plastic (e.g. cast parts). For the rest, the above statements regarding the single plug devices apply equally to the branch plug devices.

In another embodiment (not shown), a continuous screw with a rear nut is provided instead of the blind screw 57, the screw head being secured against rotation relative to the pressing section 6a in a form-fitting or frictional manner. The molded parts 26a are designed here as removable rubber caps. As a result, the nuts and the blind screw 58 can be retightened when the housing is open.

The connector systems described have grown in a special way to withstand the harsh conditions and the high safety requirements of railway operations; however, they can also advantageously be used to connect stationary high-voltage lines.

Claims (22)

Plug-in device system, designed for high voltage in the medium-voltage range, and for voltage in the area below, in particular for connecting continuous cables in railway trains, - formed by at least two complementary plug devices (2, 3) for producing at least one conductor connection, - Wherein the plug devices (2, 3) inner conductor parts (6, 7, 10, 11) and outer housing parts (8, 9), and - The conductor parts (6, 7, 10, 11) in the assembled state of the connector system (1) are completely and tightly covered with insulating material relative to the housing parts (8, 9). Plug device system according to Claim 1, in which one or more cavities (23, 25) are present between the covered conductor parts (6, 7, 10, 11) and the housing. Plug device system according to claim 1 or 2, wherein the covering of the conductor parts (6, 7, 10, 11) in whole or in part by at least one Shrink film or at least one shrink tube (26) is realized. Plug device system according to one of claims 1 to 3, in which the covering of the conductor parts (6, 7) in the plug area is achieved by a labyrinth seal and / or plug seal. Plug device system according to Claim 4, in which the plug seal comprises two sealing elements (31, 32) which overlap in the plug direction. A plug device system according to claim 4 or 5, wherein the plug seal comprises a resilient and a hard sealing element (31, 32). Plug device system according to one of Claims 1 to 6, in which, when the plug devices (2, 3) are disconnected, a labyrinth insulation is implemented in the plug area, which for connecting conductor parts (6, 7) to the housing has a relatively long path over insulating surfaces required. Plug device system according to Claim 7, in which the labyrinth insulation is realized in that one plug device (6) has an inner contact element (33) which is seated in an insulating sleeve and the other plug device (7) has a complementary outer contact element (36 ), which is covered on the outside with insulating material. Plug device system according to Claim 8, in which the outer contact element (36) additionally has an attachment (37) on the end face made of insulating material. Plug-in device system, in particular according to one of claims 1 to 9, designed for high voltage in the medium-voltage range, and for voltage in the area below, in particular for connecting continuous cables in railway trains, - formed by at least two complementary plug devices (2, 3) for producing at least one conductor connection, - The plug devices (2, 3) have live conductor contact parts (6, 7), - Which are equipped with insulating material in such a way that when the plug-in device system (1) is disconnected but ready to plug in, both plug-in devices (2, 3) make contact with live parts impossible. Plug device system according to claim 10, wherein the live parts are arranged behind sufficiently narrow gaps or passages of the insulating material. Plug device system according to claim 10 or 11, in which the live parts are frontally covered with insulating material. Plug device system according to one of claims 10 to 12, wherein a plug device (6) has an inner contact element (33) which is seated in an insulating sleeve. Plug device system according to one of claims 10 to 13, wherein a plug device (7) has an outer hollow cylindrical contact element (36), which is equipped in its interior with a central, front-end body or mandrel (38) made of insulating material, and the complementary inner contact element (33) of the other plug-in device (6) in the assembled state accommodates the central body or mandrel (38). Plug device system, in particular according to one of claims 1 to 14, - formed by at least two complementary plug devices (2, 3) for producing at least one conductor connection, - At least one of the plug-in devices (2, 3) has a one-piece conductor contact part (6, 7) which is to be pressed on the one hand with a cable end and on the other hand by touching a conductor contact part (7, 6) of the other plug-in device (3, 2) the conductor connection manufactures, - The conductor contact part (6, 7) is soft in the pressing area and hard in the plug area. Plug device system according to claim 15, in which the hard formation of the conductor contact part (6, 7) in the plug area is achieved by heat treatment. Plug device system according to claim 15, wherein the conductor contact part (6, 7) is integrally composed of at least two metal parts of different hardness. Plug device system according to one of claims 1 to 17, in which the housing parts (8, 9) serve to produce a pluggable ground connection. Plug device system according to one of claims 1 to 18, wherein the inner and the outer contact element (33, 36) and / or the contact elements (33, 36) and the housing parts (8, 9) are arranged concentrically to one another. Plug device system according to one of claims 1 to 19, in which the introduction of a cable (4, 5) into the plug device (2, 3) for the purpose of securing against rotation is designed as a kind of stuffing box with a flexible pressure element. Plug device system according to claim 20, in which between the cable (4, 5) and housing part (8, 9) a ring (54) of resilient material is pressed in the longitudinal direction of the cable. Plug device system according to one of claims 1 to 21, which consists of a set of two complementary plug devices of the following group: plug, socket, branch plug, branch socket, dummy plug, blind socket, surge arrester plug, surge arrester socket, voltage indicator plug, voltage indicator socket .

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