EP2880720A1

EP2880720A1 - Electrical device having an explosion-proof plug-in connection

Info

Publication number: EP2880720A1
Application number: EP13735308.2A
Authority: EP
Inventors: Carsten BRENNER
Original assignee: R Stahl Schaltgeraete GmbH
Current assignee: R Stahl Schaltgeraete GmbH
Priority date: 2012-08-02
Filing date: 2013-07-11
Publication date: 2015-06-10
Anticipated expiration: 2033-07-11
Also published as: US20150180162A1; CN104662747B; EP2880720B1; US9531116B2; CN104662747A; WO2014019832A1; DE102012107091A1

Abstract

The invention relates to an electrical device having a plug-in connection device (15), which is used to open and close an electrical circuit (24). The plug-in connection device (15) contains at least two contact/mating-contact pairs (22, 23), which have different ignition protection types. At least one of the two contact/mating-contact pairs is designed to interrupt the current running through said contact/mating-contact pair without triggering an explosion. (Ignition protection type Ex d or Ex i.) The other contact/mating-contact pair (23) opens and closes in the currentless state. Therefore, the other contact/mating-contact pair can have a second ignition protection type, such as Ex e.

Description

Electrical device with explosion-proof

connector

The invention relates to an electrical device with a connector for the electrical connection of several components of the electrical device.

For explosion-proof electrical equipment, it is known to provide connectors that can be used in potentially explosive atmospheres. For this purpose, EP 1 638 173 A2 proposes connectors which have a plurality of contact pins. One of the contact pins serves for contacting a surveillance conductor. This contact ^¬ pin is designed to be shorter than the other contact pins, so that he contacted in the manufacture of the connector last and disconnects when disconnecting the connector as the first. At the monitoring conductor is a voltage that is below the minimum ignition voltage. Thus, no spark can occur when opening and closing the contact point. The monitoring conductor is used to switch the power supply to and from the other longer contact pins on and off. This ensures that the at ^¬ the longer contact pins always come in current- and ^{¬-voltage-free} state in contact with the associated bushings. The combination of one of the explosion protection type Ex i monitoring conductor with other contacts that are closed or disconnected only in de-energized state requires additional switches in the connected components.

Furthermore, DE 20 2005 010 927 Ul discloses an ex- Plosionsgeschütten Connectors of type of protection pressure ^¬ solid encapsulation (Ex d). This is constructed so that the flameproof enclosure is retained until all the contacts are ge ^¬ separates.

Explosion protection through pressure-tight encapsulation of all contacts leads to a large constructional and constructional effort.

It is an object of the invention to provide an explosion-proof electrical device, which manages with little effort and is versatile.

This object is achieved with the electrical device according to claim 1:

In the electrical device according to the invention, a connector for electrical connection of two components of the electrical device is provided. Of the

A connector is used to connect two sections of an electric circuit, wherein one section is arranged in one component of the electrical device and the other section is arranged in the other component of the electrical device. The two sections together form an electrical circuit. The connector comprises a contact arrangement and a mating contact arrangement. The contact arrangement comprises at least two contact groups ^¬ a ter for the forward conductor and one of the Rücklei-. Each contact group includes at least one or more contacts. Likewise, the mating contact arrangement comprises at least two mating contact groups. Each Gegenkontaktgrup- pe comprises at least one, possibly also several mating contacts. The contacts and the mating contacts can be designed either as a plug pin or other and as ^¬ socket contact or other mating contact. The Contacts and mating contacts form contact / mating contact pairings. According to the invention it is provided here that the contact / mating contact pairings of the Hinleiters and the contact / mating contact pairings of the return conductor unterschiedli ^¬ che types of protection. This is although the contact / mating contact pairings of the Hinleiters and the return conductor are preferably flowed through by the same load current. However, the contact / mating contact groups have different first touch positions. The contact / mating contact group, which records a later contact during mating of the connector and disconnects earlier when the connector is disconnected, has a first degree of protection than the other contact / mating contact group. Thus affects the later touching and earlier separating contact / mating contact group (with the first degree of protection) as Explosionsge ^¬ protected disconnect switch for the remaining other contact / mating contact group with other (second).

The second type of protection is preferably the protection ^¬ art Ex e. The first type of protection is preferably the degree of protection Ex d or Ex i. In the case of the type of protection Ex d, it is preferred to carry out only one or a few contacts in this degree of protection. In the ignition protection Ex i, it is preferred if the contact group comprises several Kon ^¬ tact / mating contact pairings. These can be connected in parallel branches of the electrical

Circuit can be arranged. Also, they are preferably each individual current limiting circuits zugeord ^¬ net. The structural complexity of such a connector remains low. The explosion protection is realized electrically. The current limiting circuits may be associated with the connector assembly. An intervention in the electronics of the circuit to be connected is not he ^¬ required. In addition, in any of the proposed embodiments, an additional monitoring conductor is required.

In addition to the current limiting circuits, voltage limiting circuits can be assigned to the contact / mating contact pairings, in particular if the degree of protection Ex i is provided. These prevent sparking at the contacts, which are designed, for example, in the type of protection Ex i. This embodiment is particular ^¬ DERS for circuits having one or more inductors in the circuit.

Further details of advantageous embodiments of the invention are the subject of the claims, the descrip tion ^¬ or the drawing. Show it:

Figure 1 A device according to the invention, in the most schematic representation.

Figure 2 to 6 further exemplary alternative ^{embodiments of} the invention ^¬ device in each case, in a schematic block diagram representation.

In Figure 1, an electrical device 10 is illustrated schematically ^¬ table, which is operable in explosive environment. The electrical device 10 comprises at least two components 11, 12, which cooperate electrically. For example, the component 11 may be one or more electrical consumers included, such as for example, light sources ^¬, motors, sound generator or other electrical components or apparatus such as computer or the like. All such consumers are symbolized in FIG. 1 by a resistor 13. Its impedance can be purely ohmic, purely reactive or complex. Moreover, the first component may contain 11 not further illustrated or current ^¬ voltage sources.

The second component 12 includes at least one tension ^¬ voltage source 14, which feeds the electrical load. 13 The voltage source 14 may be of any suitable type. It may be formed, for example, as a rechargeable battery, as a power supply, as a primary battery, as a supercapacitor or as another memory. The second component 12 may include a plurality of such voltage sources 14 in series or parallel connection. In addition, the second component 12 may include electrical loads.

In order to feed the consumer 13 by means of the voltage source 14, the two components 11, 12 are electrically connected to each other. For this purpose, a connector device 15, which is symbolized in Figure 1 by a long / short dashed quadrangle.

To the connector device 15 includes a contact assembly 16, which comprises at least two Kohntaktgruppen 17, 18. The contact group 17 comprises at least one contact 17a or several such contacts. The contact 17a (and optionally further to the same contact group 17 associated contacts), for example, as Steckkon ^¬ clocks or alternatively be designed as a socket contacts.

The second contact group 18 comprises at least one contact 18a or optionally also a plurality of contacts. The contact 18a and optionally further can be designed as Steckkon ^¬ clocks or as a socket contacts.

To the connector device 15 also includes a mating contact assembly 19 which includes a first mating contact group 20 and a second mating contact group 21. The first mating contact group 20 has a mating contact 20a and possibly further mating contacts. The second mating contact group 21 has at least one counter ^¬ contact 21 a and optionally further mating contacts. The mating contacts 20a, 21a of the two mating contact groups and optionally further be associated to the groups formed ^¬ counter contacts can be used as plugs or sockets.

The contact 17a and the mating contact 20a form together men ^¬ a contact / mating contact pairing 22. The contact 18a and the mating contact 21a constitute a contact / Ge ^¬ genkontakt pairing 23rd

The contact / mating contact pairings 22, 23 form the forward conductor and the return conductor, which electrically connect a first section 25 to a second section 26 in a circuit 24. The first section 25 is arranged in the first component 11. The section 25 contains the electrical load 13. The second section 26 is arranged in the second component 12 and contains the source 14.

Overall, the plug connector 15 fulfills a high type of protection, such as, for example, Ex d or Ex i. In addition, the the contact / mating contact pairs 22, 23 different types of protection. In this case, that contact / Gegenkontakt- pairing (here the pairing 22), when connecting the

Connector 15 last receives electrical contact and at the same time is the one who first disconnects the electrical current path when disconnecting, in the ers ^¬ th degree of protection, here, for example, Ex d formed. The Zündschutz ^¬ art Ex d is achieved for example by an enclosure of the counter contact group 20 and the mating contact 20a, which defines a gap 28 with the contact group 17 and the contact 17a, which is so long and so narrow that in case of explosion within the enclosure 27 from the gap 28 neither flames nor glowing particles escape.

The other contact / mating contact pairing 23, however, is executed in the second type of protection, for example. Ex e. It is considered to be static electrical contact, which only closes or disconnects when it is de-energized. The currentlessness is effected when closing by the lead V and when opening by the lag N, with which the contact 18a operates in comparison to the contact 17a. The lead V and the lag N can be achieved in the simplest case by a length difference of the contacts 17a, 18a. Alternatively or additionally, a position or length difference of the mating contacts 20a, 21a may be provided.

The premature closing of the contact / counter contact Pa ^¬ tion 23 and the lagging opening the same can be achieved alterna ^¬ tively by other means. Beispielswei ^¬ se may comprise the connector 15 other means to always permit only the electrical contact between the contact 17a and the mating contact 20a when the contact 18a and the mating contact 21a are already in a safe contact. These means can also be provided to secure the contact 17a and the mating contact 20a disconnect before the contact 18a and the mating contact 21a separate. For example, insulating elements may be provided for this purpose, which move the contact 17a and the contact 20a in a direction other than the insertion direction (eg transversely thereto) and thus close or disconnect, if the connector is to be made or disconnected.

The device 10 works as follows:

When the components 11, 12 are provided, the connector device 15 is initially in a disconnected state. If the contact arrangement 16 is then connected to the counter-contact arrangement 19 by being moved toward one another, the contact / counter contact pairing 23 first closes. This takes place in the de-energized state because the circuit 24 has not yet been closed. The circuit 24 closes as soon as the contact 17a is inserted into the housing 27 and comes within contact with the mating contact 20a. This may possibly cause a spark that ignites in the housing 27 located ignitable mixture. The enclosure 27 is sized to withstand the resulting explosion. Occurring overpressure can be reduced by the gap 28, wherein the length and small width of the gap 28 prevent the escape of flames or glowing particles. Likewise, the conditions when a spark occurs within the housing 27 when disconnecting the connector means 15.

Because only one of the two contact / mating contact Anord ^¬ calculations 22, 23 closes and disconnects in the energized state, namely the mating 22, can be dispensed with in the other mating 23 on a Explosionsschüt zende housing. Thus, according to the present concept, a small simply constructed, little space-consuming connector 15 can be designed, which in explosion-endangered Environment is used.

Figure 2 illustrates a modified form of the execution ^¬ device 10. The above description is on the basis of the reference numerals already introduced accordingly. The consumer 13 and the voltage source 14 are symbolically arranged by blocks. These can meh ^¬ eral or many electrical or electronic components including, current and voltage sources resistive elements in reactive elements or the like.

It can be seen that the contact / mating contact pairing 23 may comprise a plurality of contacts 18a, 18b and mating contacts 21a, 21b. These are electrically parallel ge ^¬ on. Preferably, they are arranged on both sides of the con tact ^¬ / counter contact pairing 22nd This provides protection against skewing when pulling and plugging. By a built-in or externally mounted me chanical ^¬ guiding the to be plugged portion ^¬ an oblique position is prevented. If the contacts 18a, 18b and counter ^¬ contacts 21a, 21b arranged at different opposite sides of the contact / mating contact pairing 22, can also be dispensed with a parallel guide, because even with inclined position of the corresponding connector parts a safe forward or lagging the contacts 18a, 18b sheared.

A further advantage of the use of a plurality of, for example, parallel contacts 18a, 18b or mating contacts 21a, 21b in the lead leading on closing and lagging when opening contact / mating contact pairing 23, lies in the avoidance of latently dangerous current flow interruptions during sliding of the contacts 18a, 18b in or on the mating contacts 21a, 21b, for example as a result of dust or dirt deposits on the contact surfaces. In the above-described embodiments of Figures 1 and 2, the contact / mating contact Pa ^¬ tion 22 in protection Ex d is executed. The other con ^¬ tact / mating contact pairing 23 is carried out in the protection Ex e when plugging before and while pulling lagging. As a result, the circuit is opened when opening the Ex d contact si ^¬ cher before the Ex e disconnects connection. When closing the Ex e contact is already closed until the trailing Ex d contact closes the circuit. The Kon ^¬ clocks and mating contacts can be executed as mentioned in each case several times and connected in parallel. This applies to the Ex e contacts as well as to the Ex d contacts.

Another variant of the combination of different degrees of protection can be taken from the embodiment according to FIG. Here are several contact / mating contact pairings 22 with contacts 17a, 17b, 17c and mating contacts 20a, 20b, 20c without single or common housing in the

Closing lagging and provided for opening the construction provided. The contacts and mating contacts are subject to the type of protection Ex i. the contact mating contact pair 23 is again embodied in the type of protection Ex e The current ^¬ circle 24 is, as far as it passes through the contacts 17 a to c and Ge ^¬ genkontakte 20 a to c, divided into mutually parallel branches 29, 30, 31. In these branches, at least in one of the components 11, 12, preferably in both,

Current limiting devices 33 to 38 are provided. These may involve ohmic resistances or complex cons ^¬ stands or electronic circuits which switch off when reaching a limit current or limit this current. Such current limiting circuits can be constructed with transistors or other electronic components or integrate circuits which monitor flowing current and throttle if necessary.

As can be seen, the principle lies in the fact that one of the conductors (forward conductor or return conductor) is guided in multiple poles over several Ex i contacts. The circuit 24 is divided into several intrinsically safe circuits. The Ex i contacts take over the activation of the circuit before the separation. Regardless of the degree of protection Ex i for the contact / mating contact assembly 22, the components 11, 12 also fully or partially encapsulated may be ausgebil ^¬ det.

As illustrated in FIG. 4, in addition to the configuration described in connection with FIG. 3, a voltage limiting device 39 may be provided which limits the voltages occurring at the contacts Ex i of the contact / mating contact pair 22. For example, this can be done by voltage limiting diodes, for example Z-diodes 40, 41, 42, which are connected to the branches 29, 30, 31 and which are connected to a common ground potential. Al ternatively ^¬ the connection point of the Zener diodes 40 to 42 46 may be connected to a suitable location of the circuit 24 in the respective walls ^¬ ren component, here the component 12 and over a contact / mating contact pairing. The Zener diodes 40 to 42 can resistors 43, 44, 45 may be pre ^¬ switches, again to limit the current occurring. Otherwise, the previous description applies accordingly.

As Figure 5 illustrates, the embodiment may be modified in accordance with FIG 4, that the clamping ^¬ voltage source 14 is separated into individual voltage sources 14a, 14c to be formed. Again, the circuit 24 is divided into individual Ex i circuits in different branches 29, 30, 31. The number of these individual branches results from the desired current flowing through the load 13 and the current load provided at each contact 17a-c. The contact / mating contact pairing 23 is preferably in turn an Ex e contact. The previous write-Be ^¬ otherwise apply accordingly.

Figure 6 illustrates a modified execution ^¬ form in which a plurality of protection according to Ex i ^¬ making te cooperating contact / mating contact pairings with a 23 designed according to the Ex d protection contact / mating contact pairing 23rd With regard to the design of the contacts 17a, 20a and the contacts 18 (a, b, c) and mating contact 21 (a, b, c), reference is made to the previous description. The switching contact here is the contact against Kontaktpaa ^¬ tion 22. This is provided with the housing 27, which provides the explosion protection. The arranged in the branches 29, 39, 31 contact / mating contact pairings 23 are the leading during insertion and trailing when pulling contact pairings. They are current limiting devices 33 to 35 before and / or downstream. In addition, a voltage limiting device 39 may be provided.

Turn 24 is divided into a plurality of intrinsically Siche ^¬ re circuits or branches 29 to 31 of the circuit. Thus, one of the conductors (forward conductor or return conductor) is routed via multiple contacts via Ex i contacts. The other conductor is routed via one or more contact / mating contact pairings designed according to the Ex d criteria. A current and / or voltage limitation may be 12 pre see ^¬ both the component 11 and additionally or alternatively in the component. The voltage limiting device 39 can be supported on internal ground circuits on the ground. For external circuits, a connection can be provided on the model of Figure 4. It may be the two components 11, 12 completely or partially encapsulated (eg Protection type Ex d or Ex m) may be formed.

All embodiments with a plurality of contacts 17a-c or 18a-c, in particular according to FIGS. 5 and 6, can be used to design a bus system. For example, the respective contacts 17a - 17c (Figure 5) or 18a - 18c to be (Fi gur ^¬ 6) is designed as bus lines. The voltage ^¬ source 14 may be housed in the component. 11 The module 12 or a plurality of parallel modules 12 can then be plugged onto the bus lines. But it is also possible to use the contacts 20a - 20c or 21a - 21c as bus ^¬ lines. In turn, one or more components 11 can be attached to these bus lines belonging to the module 12. In both of these cases, the bus lines may be flexible or inflexible insulated or bare lines.

The above embodiments are described in connection with contact / mating contact pairings 22, 23, the side by side, aligned parallel to each other aligned contacts 17, 18 and mating contacts 20, 21 aufwei ^¬ sen. But it is also possible, at least one contact / Ge ^¬ genkontakt pairing (eg 23) in such a way that it concentrically surrounds the other contact / mating contact pairing 22. In such an example, coaxial arrangement, the contact / mating contact pairing 23, the Ex d housing for the contact / mating contact pairing 22 (and optionally further, eg 46) form.

In an electrical device, a connector device 15 is provided, which for opening and

Close a circuit 24 is used. The connector ^¬ tion device 15 includes at least two contact / mating contact pairings 22, 23, which are designed in different types of protection. At least one of the two Contact / mating pairing is designed to separate the current passing through them without causing an explosion. (Type of protection Ex d or Ex i). The other contact / mating contact pairing 23 opens and closes when de-energized. It can therefore be designed in the second type of protection, for example Ex e.

Reference sign list:

10 setup

11 first component of the device 10

12 second component of the device 10th

13 electrical consumers

14 voltage source

14a ^■ - c single voltage ^source

15 connector device

16 contact arrangement

17 first contact group

18 second contact group

19 mating contact arrangement

20 first counter contact group

21 second counter contact group

22 contact / mating contact pairing

23 contact / mating contact pairing

24 circuit

25 first section of the circuit 24th

26 second section of the circuit 24th

27 enclosure

28 gap

V advance

N lag

29 - 31 branches

33 - 38 current limiting devices

39 voltage limiting device

40 - 42 Z-diodes

43 - 45 resistors

46 contact / mating contact pairing

Claims

Claims:

1. An explosion-proof electrical device (10) with a plug connector (15) for the electrical connection of two components (11, 12) of the electrical device (10): with an electrical circuit (24) having a first of the components (11, 12) having associated first portion (25) and a second of said components (11, 12) associated with the second portion (26), said portions (25, 26) are electrically ge ^¬ connected in series, with a contact assembly (16) comprising at least two contact groups (17, 18), which are electrically connected to the first portion (25), with a mating contact arrangement (19) having at least two mating contact groups (20, 21), the

are electrically connected to the second portion (26), wherein the contact groups (16) and the Gegenkontaktgrup ^¬ pen (19) each form contact / mating contact pairings (22, 23) with at least two different types of protection.

2. Device according to claim 1, characterized in that both contact / mating contact pairings (22, 23) are flowed through by the same current.

3. Device according to claim 1 or 2, characterized in that each contact group (17, 18) one or more contacts (17a, 17b ...; 18a, 18b ...) and / or that each mating contact group (20, 21) has one or more mating contacts (20a, 20b ...; 21a, 21b ...).

4. Device according to one of the preceding claims,

characterized in that the contact / mating contact groups (22, 23) have different Erstberührungspositi- onen.

5. Device according to one of the preceding claims,

characterized in that the contact / mating contact group (22) with the first degree of protection for a later contact and an earlier contact separation are ^rich tet and that the contact / mating contact group (23) with the second degree of protection for a previous contact and a later contact separation are set up.

6. Device according to one of the preceding claims,

characterized in that the second type of protection is the degree of protection ex-e.

7. Device according to one of the preceding claims,

characterized in that the first type of protection is the degree of protection ex-d.

8. Device according to one of the preceding claims, characterized in that the first type of protection ^{¬ the} type of protection ex-i.

9. Device according to one of the preceding claims,

characterized in that only a single contact / mating contact pairing (22) has the first degree of protection.

10. Device according to one of claims 1-8, characterized in that a plurality of contact / Gegenkontakt- pairings (22, 23) in mutually parallel branches (29, 30, 31) of the electric circuit (24) are arranged.

11. Device according to claim 10, characterized in that each of the branches (29, 30, 31) contains at least one current limiting circuit (33-38).

12. The device according to claim 11, characterized in that in one, several or all branches (29, 30, 31), the current limiting circuit (33 - 38) in only one of the sections (26, 27) is arranged.

13. Device according to claim 11, characterized in that in one, several or all branches (29, 31) in both sections a current limiting circuit (33-38) is arranged.

14. Device according to one of the preceding claims,

characterized in that in one of the sections (25, 26) a voltage limiting circuit (33 - 38) is arranged.

15. Device according to claim 14, characterized in that the voltage limiting circuit (39) to a contact / mating contact pairing (46) is connected, which has the first of the degrees of protection (ex d) and the former contact position and the subsequent Kontakttrennposi ^¬ tion.