DE19949649A1 - Power supply for explosion-protected electronic functional units - Google Patents

Abstract

The invention relates to a device for converting signals between actuators or sensors (3) that receive and / or transmit and in particular receive analog signals via a signal line (6) and, in particular, receive digital data via a data line (7) / or transmitting master computer (1) of a signal transmission, in particular a fieldbus system, comprising DOLLAR A a) an operating voltage supply (9), DOLLAR A b) a module carrier (4), DOLLAR A c) one or a plurality of on the module carrier (4) modules (5), DOLLAR A d) which can be plugged in or removed from during operation of the fieldbus system, an operating voltage connection (11, 15) between module carrier (4) and module (5), DOLLAR that can be released when the module (5) is removed A e) a data transmission connection (10, 14; 12, 16) that can be released when the module (5) is removed between the module carrier (4) and module (5). DOLLAR A To increase operational reliability, it is provided that DOLLAR A f) the operating voltage supply on the module carrier (4) is an AC voltage and DOLLAR A g) the operating voltage connection (11, 15) can be separated essentially without sparking.

Description

The invention relates to a device for Energiever supply for explosion-protected functional units.

The problem of supplying energy to such functions units consists in that when the Functional unit from the power supply no sparks may arise. It is known in the prior art the transferable energy, for example through resistors to reduce such a degree that when opening the Leads no sparks. The disadvantage is that heat generated in the resistors.

The invention further relates to a device for Power supply of a variety of on one common Men carriers of pluggable electronic functional units in a hazardous area from a Be drive voltage source. It is in the prior art known, on a carrier board a number of plug perform in which functional units, For example, plug-in cards or other modules can be inserted can. Data line con clocks closed and power supply line contact te.

It is also known in the prior art to use energy in Transferring the form of alternating current via plug contacts, which form a separable transformer.

The invention is based on the object at the outset Devices described safe to operate design.  

First and foremost, the task becomes solved that the energy extraction by a choke he follows. The choke is preferably made by a condenser sator or a coil formed. The capacity of the The capacitor or the inductance of the coil is included in this way to the output frequency of the output AC voltage adjusted that there is a suitable blind resistance results. Suitable reactances can be found in Range between 1 and 1000 ohms. As capacities preferably values between 1 nF and 10 nF come in Consideration. Coils from 1 µH to are used as choke coils 10 µH preferably used. The output voltage has preferably a frequency between 200 and 300 kHz. The throttle elements can be used in both power supplies lines are switched on, for example the choke consist of two capacitors or two coils.

The task is further solved in that the Operating voltage is an AC voltage and the radio tion units and the carrier or the company chip Source and the carrier each have a core and wick part of a separable inductive Have transformer. In particular, that is the carrier assigned transmission part either current controlled in Series or individually pre-connected mechanically in Series or electrically connected in parallel. As a result this configuration, it is possible with a common a variety of functional units to provide energy, with individual functional units during the operation of the other functions units can be inserted or removed as required. At series-connected coils of the transformer parts the changed inductance when plugging or unplugging compensated by a current regulation that compensates for increasing or decreasing reactance.  

The coils of the transformer parts are shuttered in parallel tet, each coil is preceded by a switch. With This circuit can be used for each individual coil individually be activated or deactivated. Preferably done the wiring by inserting or removing the Functional unit. The element upstream of the coil can be designed as a magnetic switch (reed contact). In this case the plug-in card carries a magnet, which activates the reed switch when the card is inserted, so that the primary coil of the transformer is energized. But it is also provided that the ballast is formed by a throttle. This can be yours Change reactance when inserting the card. Here in particular, the core of the throttle is made from a the magnetic saturation drivable material det. The card then carries a magnet that goes into the Near the choke brought the core into the satti supply drives. It can also be provided that the core the throttle forms a gap. In this gap When inserting the card, a coil is immersed in the is short-circuited. This coil can be used as a planar coil be trained.

In a preferred variant of the invention, it is provided hen that the operating voltage supply from two changes voltage sources exist, which are electrically isolated are. The primary sides of the transmitters then have two primary coils, each primary coil with one AC power source is connected. If one fails Power supply can full power through the other Power supply are provided. In a first mode it is intended that the power control of the two Power supplies over the phase position of the two AC voltages conditions. In a second operating mode, the Power control of the two power supplies is phase locked  by adding the primary voltages. The Power control of the two power supplies can be done via the Phase position of the two AC voltages take place. The the two primary voltages can add up. The ampli The two primary voltages can be of equal magnitude his. The amplitudes of the two primary voltages can but also partially subtract. If a network partially faulty, it can only achieve full performance others the excess performance by subtracting the Compensate primary voltages. The increase in performance can also be achieved by combining both operating modes take place, with both the amplitude being varied as also the phase.

The primary voltage applied can be sinusoidal. On Operation with triangular or trapezoidal or rectangular voltage gene is also provided. The individual impulses can gaps or changing pulse / pause ratio have nits. With several primary windings, the Curve shape of the primary voltages also different his. On the secondary side, one or more Secondary coils can be provided. Become the primary coils operated in series, it is provided that at least a minimum current flows through a secondary coil.

The invention further relates to a device for converting signals between actuators or sensors, which are arranged and / or transmit in a potentially explosive area, in particular analog signals, and a master computer of a fieldbus system which receives and / or sends digital data, in particular, via a data line. A large number of signal lines, each of which is connected to an actuator or sensor, lead to a known device for signal conversion. Actuators and sensors are located in the potentially explosive area and are equipped accordingly so that they can be used there. The known signal converter is located outside of the potentially explosive area and is connected to a master computer via a data line. The signal converter has in particular:

• a) at least one operating voltage supply,
• b) a module carrier,
• c) one or a plurality of on the module carrier pluggable during operation of the fieldbus system or removable modules,
• d) an operating chip that can be detached when the module is removed Connection between module carrier and module and
• e) a data transfer that can be released when the module is removed connection between module carrier and module.

The operating voltage is supplied by a pre switched power supply, which was a DC voltage finished, tapped from the module via plug contacts can be. The known modules are around plug-in cards in the form of circuits Circuit boards. The data transmission connection is also made through a plug connection.

This variant is a generic signal Conversion device trained so that it is internal use in such a way within the potentially explosive area can be detected that during operation of the fieldbus Systems subtracted the individual modules from the module carrier can be or on the module carrier again can be stuck.

It is provided that the module carrier with a AC voltage is powered and that  essentially spark the operating voltage connection is freely separable. As a result of this configuration the individual modules also in hazardous areas Area from the module carrier without being damaged sparks that cause an explosion in particular occur when disconnecting the operating voltage connection. This type of power transmission between the network part and the module carrier provided, so can Power supply cards without sparks arising from the front direction pulled out for the purpose of maintenance, for example become. The energy feed is preferred by one separable, inductive transformer. Here the separable transformer can be a first, fixed to the Module carrier connected, receiving a primary winding Core half and a second, firmly connected to the module ne, having a secondary winding core half sen. Is this connection between the power supply and the module provided primary, so are the primary winding on the power supply cards. The secondary windings are located on the module carrier board. The operating The voltage connection thus consists of a two-part system gene transformer, the one transformer half the module carrier and the other half of the transformer Module is assigned. When plugging in the module the module carrier then forms in particular bringing the two core parts into contact on the Interface a fully functional transformer out of the the operating ac voltage on the module transmits. In particular, it can be provided that the primary winding consists of two half-windings, the half-windings each of the rows next to mutually lying primary core halves connected in series are and the half-windings of the last primary core half te of the series are interconnected. Furthermore, be provided that the secondary winding a variety  of electrically isolated individual windings. This has the advantage that a large number of modules of switching channels can be arranged, according to the large number of primary windings galvanically from one another who are separated. The separable transformer can Operating voltage also up or down transformie ren. In particular, it is provided that the primary chip voltage is, for example, approximately 20 volts and the secondary voltage is a highly transformed voltage 30 volts, for example. To be as efficient as possible The change is to ensure power transmission voltage preferably in the high frequency range and there in the range from 200 to 300 kHz. It can also be provided be that the operating voltage through reactors is limited. This measure too is ensures that sparking when pulling the Card is suppressed. The reactance can are also in the circuit of the secondary windings. From the operating alternating voltage can be on the modules a DC operating voltage can be obtained again. It can also be provided that both lines of the Power supply one capacitor each for power have limitation. The modules are especially for carriers of electronic circuits. It but it can also be provided that the modules are single Lich are plug elements that are removed from the Signal conversion device arranged circuit like to be wired. The operating AC voltage, which is transferred to the modules can be from a DC voltage can be obtained.

Another variant of the invention provides that the Modules via electrically conductive connections on the part of the module carrier is supplied with the operating voltage become. In this case is the power supply side contact  a throttle upstream. This throttle is there from a coil and a ferrite core. One each Module slot can be a choke on the module carrier be assigned. The choke can be designed as a planar coil forms, the respective coil essentially only the two outer legs of the particular E-för Some coil core is assigned which leg Reach through the openings of the module carrier board. The Choke coil is also preferred by a volliso mated conductor track of a multilayer board det. The conductor track is each about 1 mm strong epoxy layer on the outside and a about 0.5 mm thick epoxy layer to the other conductor iso liert. The essentially E-shaped coil cores lie on the carrier board in a row next to each other. This enables inexpensive collective mounting. To do this covered the entire row by a U-shaped bar gen and held. Assembly is simplified if one of the two core halves of the choke core with the Board is glued, the legs be richly through the openings of the board Then the kernels are from the other side by gluing on the associated core counterparts closed. On both sides of the board then the support of the U-shaped bar over the respective towards core halves. The strips are at the ends by Ver fasteners in the form of rivets or screws connected with each other. The parameters of the choke coil, such as core material, coil diameter and winding number are chosen so that the permeability essentially Chen is temperature constant, and that over the entire Range of control of the operating voltage supplier supply, in particular in the event of a short circuit occurring maximum value of the B field.  

Another variant of the invention relates to the lei power limitation on one module. The throttle used to limit the power needs not physically independent according to this variant to be available. Rather, it is intended that the Effect of the throttle is provided by a transformer. For this purpose, a transformer with a magnetic secondary conclusion used. Here are the parasitic inductors activities of the transmitter designed accordingly large. The leakage inductance of the transformer can, for example. 4 to 10% of the total inductance or more. To realize such a transmitter can the core of the transmitter from two elongated U- Halves exist. The resulting four-gift lige, rectangular ring-shaped core bears on its narrow side legs each the primary coil or Secondary coil, so that they are relatively far apart are spaced. Between the two these legs connecting legs can be a secondary build final field. In a further training of the Erfin can be provided that primary coil and Secondary coil, each constructed as a planar coil, be overlap in abundance. For example, the primary spu le be formed by a first conductor track layer and the secondary coil from a second trace layer.

Another variant of the invention relates to a white training of the power supply. The supply voltage two The power supplies become separable Transmitter fed to the carrier, the secondary spu le of the transformer to the carrier and the primary coil of the Power supply board is assigned, with the second only when plugged in and supplying voltage Power supply is connected to the secondary circuit. On the  A switch can be provided in this case, which the coil only switches when it is operated by an inductor alternating field is applied. This switch can be designed as a relay, which by a in Pri circuit of the power supply switched auxiliary transformer is energized. The supplied by the auxiliary transformer te voltage and low power is over conductive Contacts supplied to the carrier board. Alternatively, you can the auxiliary transformer can be a separable transformer. The primary coil can be the power supply and the secondary coil be assigned to the module carrier. The plug contacts can then be omitted.

Embodiments of the invention are as follows explained with the accompanying drawings. Show it:

Fig. 1 is a schematic representation of a fieldbus system according to the invention;

Fig. 2 is a schematic view of a module;

Fig. 3 is a schematic representation of a module carrier;

Fig. 4 is a schematic representation of a separable transformer;

Fig. 5 shows a first circuit example;

Fig. 6 shows a second circuit example;

Fig. 7 shows a third circuit example;

Fig. 8 is a first circuit diagram of a Leistungsbegren wetting;

Fig. 9 is a second circuit diagram of a Leistungsbegren wetting;

Fig. 10 shows a second embodiment of a module carrier;

Figure 11 is an enlarged section along the line XI-XI in Fig. 10.;

Figure 12 is a section of a module carrier of another embodiment in an enlarged view.

Fig. 13 is a section along the line XIII-XIII in Fig. 12;

Fig. 14 shows another embodiment of a Be circuit of a module carrier;

Fig. 15 shows an embodiment of a Vorschaltelemen tes;

Fig. 16 shows another embodiment of a pre-switching element,

Fig. 17 shows another circuit example of a signal conversion device;

Fig. 18 shows another embodiment of a signal conversion apparatus;

FIG. 19 is an embodiment of an operating voltage supply len with two redundant Netztei;

FIG. 20 shows the phase relationship of the two power supplies in the exemplary embodiment according to FIG. 19 in a first operating variant; FIG.

FIG. 21 shows a representation according to FIG. 20 in a two-th operating variant;

FIG. 22 shows a representation according to FIG. 20 in a third operating variant;

Fig. 23 is a schematic representation of a leistungsbe adjacent throttle in the power supply of the module slots;

Fig. 24 shows a variant for a power-limiting module for throttling slot power supply;

Fig. The example of an AC voltage or an alternating current with which the throttle beauf beat is 25;

Fig. 26 is a schematic representation of the construction of a choke;

Figure 27a the configuration of a planar coil for a throttle on a first conductor track.

FIG. 27b shows a representation according to FIG. 23a of the continuation of the planar coil on a second conductor track; FIG.

FIG. 28 is a section through a multi-layer printed te;

FIG. 29 is a schematic representation of an assembled core throttle in section;

FIG. 30 is the schematic representation of the assembly of a plurality of adjacent reactors in series;

Fig. 31 is a schematic representation of a transformer with a large magnetic shunt;

Fig. 32 shows the electrical equivalent circuit diagram;

Fig. 33 shows the example of an embodiment of a transformer similar to the throttle shown in Figures 27a and 27b;

Fig. 34 is a circuit diagram of a power supply of a module;

FIG. 35 is a section of a module carrier TIC on the secondary coil of a two network cards redundant clamping voltage supply;

Fig. 36 is a circuit example of a carrier to a module infected power board;

FIG. 37 is a field bus system in which the throttle is arranged on an explosion in the protected area, angeord Neten connection terminal;

FIG. 38 is a circuit example of a throttle;

FIG. 39 is another example circuit of a choke;

Fig. 40 shows a first example of a power supply according to the invention;

Fig. 41 shows a second embodiment of a power supply to the invention OF INVENTION;

Fig. 42 is a circuit example of an inventive energy supply and SSE

Fig. 43 shows another circuit example for a Dros sel.

The fieldbus system shown in Fig. 1 consists of a host computer 1 , which is connected by means of a digital data line 7 to a device for signal conversion 2 . A power supply unit 9 and a module carrier 4 are located in the signal converter 2 . The module carrier 4 has a plurality of data transmission connection plug openings 14 , 16 and an element 15 for the operating voltage connection Be. The module carrier 4 is also able to carry a plurality of, preferably sixteen, modules in the form of plug-in cards. The individual plug-in cards 5 are plugged into the corresponding plug connections 14 , 16 of the module carrier 4 by means of plugs 10 , 12 . The cards 5 can be inserted and / or removed during operation of the fieldbus system.

Two different data transmission connections 14 , 16 are provided. There are first data transmission connections 14 , into the connector 10 of the card 5 . The data transmitted via this are transmitted to the host computer via the digital data line 7 or come from the host computer 1 . The plugs 12 of the module card 5 engage in plug openings 16 of the module carrier 4 . The data transmitted via this data connection 12 , 16 are the analog or digital signals that come from the sensors 3 or reach the actuators 3 via an analog or digital signal line 6 .

Overall, the signal conversion device can be designed in the form of an all-metal housing or a plastic housing. On the rear wall of the module carrier 4 is arranged in the form of a circuit board with reihenför mig arranged plug connections 14 , 15 , 16 for an insertion of the modules 5th To provide the operating voltage, a power supply 9 is provided. The power supply 9 generates an AC voltage. Like the signal conversion device, the sensors / actuators 3 are located in a potentially explosive area 8 .

In a first embodiment, the operating alternating voltage is transmitted to the module carrier via an inductive converter consisting of two halves 11 , 15 . The two converter halves 11 , 15 each consist of an essentially E-shaped core half 17 , 18 , the core half 17 assigned to the module 5 being arranged on the edge of the module with the free E legs pointing outwards. The assigned to the module carrier 4 core half 18 with the free E-legs in the card insertion direction, so that when you insert the card the ends of the E-legs of the core halves 17 , 18 touch. The middle E-leg of each core half 17 , 18 carries a coil 19 , 20 . The primary coil 20 , which sits on the core half 18 of the module carrier 4 , is preferably operated with an AC voltage of a few volts and a frequency of 200 kHz. The secondary coil 19 can consist of a plurality of secondary coils 19 '. The alternating voltage 22 induced in the secondary coil 19 can be rectified on the module carrier 5 by rectifiers (not shown). This rectified voltage can be used to supply power to circuit elements arranged on the module carrier.

In the embodiment shown in FIG. 5, a primary AC voltage 21 is applied to the primary winding 20 of the two-part transformer. In the secondary winding 19 , an alternating voltage 22 of in particular 30 volts is induced. This induced AC voltage is transmitted to a circuit 25 via capacitors 23 , 24 connected in each of the two supply voltage lines. The circuit 25 relates to a channel of a sensor 3 or an actuator 3 . On the card 5 , a plurality of channels 25 are net angeord. Each channel 25 is connected to the secondary winding 19 via a pair of capacitors 23 , 24 . A power limitation is generated by these capacitors 23 , 24 .

In the embodiment shown in Fig. 6, the secondary winding of the two-part transformer is formed in several parts. A total of four galvanically isolated secondary windings 19 'are shown merely by way of example, in each of which an AC voltage 22 is induced. The induced alternating voltage is in each case supplied via capacitor pairs 23 , 24 to a signal evaluation circuit 25 .

In the embodiment shown in FIG. 7, the operating AC voltage is not transmitted to the module 5 via a separable transformer. In the exemplary embodiment according to FIG. 7, a plug connection 27 for transmitting a power-limited alternating voltage is provided between module carrier 4 and module 5 . The circuit shown in FIG. 7 first has an AC voltage generator 22 , which generates a particularly high-frequency AC voltage 26 . Each connector 27 for transmitting the operating voltage is a power limiter in the form of a pair of condensers 23 , 24 upstream. The capacitor 23 , 24 is connected in each of the two lines of the supply voltage. The amount of the power to be transmitted via the connector 27 is determined by the capacitance of the capacitor pair 23 , 24 . The performance is so limited that there is no significant sparking when the card is removed from the connector 27 . The power limitation can also be achieved with a coil. On the card not shown, there is a circuit 25 for signal evaluation of the channel. The assigned to the channel 25 te signal is given via a likewise power-limited signal coupling connection 28 to an analog signal line 6 or comes from such a signal line 6 .

In Fig. 8, a power limiting circuit is provided, by means of which an AC voltage generated by a high-frequency alternating current generator 26 is converted into a power-limited DC voltage. A capacitor 29 , which is connected to the AC circuit and is located in front of a rectifier 30 , serves for this purpose. A smoothing capacitor 31 and a plurality of zener diodes 32 are located behind the rectifier 30 .

In the exemplary embodiment in FIG. 9, the alternating current generated by the alternating current generator 26 is limited via a choke 33 . The rectifier 30 is located behind the choke 33 . The circuits shown in FIGS . 8 and 9 can in particular be arranged on the module carrier and the AC voltage generated by a central voltage supply 26 can be individually limited for a module and transmitted to the module as DC voltage.

The ger the Modulträ 4 associated core halves are carrier at the position shown in Fig. 10 variant of a module shown by the reference numeral 18. The primary winding 20 can be designed as a conductor track on the module carrier 4 forming circuit board and each surround the central core leg in the form of semi-windings 20 '. The two lines of the operating voltage each form a half-winding 20 ', the two half-windings 20 ' lying opposite one another. The individual half-windings 20 'lie next to one another in rows in such a way that the last half-windings 20 "lying in the row are connected to one another. In this exemplary embodiment, the operating AC voltage is approximately 1 volt.

The Zener diodes shown in FIGS. 8 and 9 can also be supplemented by adding a power transistor. The signal converter according to the invention generates only low surface temperatures on the components, so that it can be arranged directly in the potentially explosive area. The thermal power losses are reduced due to the reactance. As a result of the configuration according to the invention, it is ensured that the individual modules 5 can be removed and plugged in without sparking. It is irrelevant whether circuits 13 themselves are arranged on the modules 5 or whether the modules are merely plug parts and are connected to circuit carriers via a cable connection.

The novelty of the device according to the invention is that there is a spark through the divisible transformer free plug connection is guaranteed and a current Limitation in the AC circuit through reactors is achieved, which of capacitors or of coils can be formed. In this resistance network can have both complex and real resistances to be available. It is also important that a common energy transfer via the module carrier takes place, with all primary coils either in parallel or can be connected in series. The primary circles can be as Planar coil can be realized on the module carrier.

In a preferred embodiment, two redundant power supplies 9 are provided. In order to introduce the energy from the two power supplies into the "magnetic plug contacts" in a galvanically separated manner, the primary winding can consist of two effecting, independently working primary coils. FIG. 11 shows a first primary winding with the reference number 20 ′, which consists of a planar coil on a circuit board side of the carrier 4 . On the back of this board there is another planar coil 34 , which belongs to the second power supply. When execution example in Fig. 12 35 surrounds a planar coil spirally the middle leg of the core 18. Through-plating 36 continues the planar coil 35 on the opposite side of the board.

In the parallel feeding of the primary windings 20 shown in FIG. 14, a primary element 37 is connected upstream of each primary winding 20 . These ballast elements 37 can be switches, for example a reed switch. The functional unit 5 to be inserted into the plug contact can have a magnet actuating the reed switch, so that when the functional unit 5 is inserted, the switch 37 closes so that the coil 20 can be supplied with alternating current. However, it is also possible for the function carrier 5 to carry a magnet 40 which, when the module 5 is inserted, is in the immediate vicinity of a throttle 37 which forms the ballast element 37 . The choke 37 may have a core made of a material which can be driven into magnetic saturation. During normal operation, this choke can be used as a current limit. Another alternative of such a control inductance is provided. This is shown in Fig. 16. There, the choke 37 has a core 39 with a gap. A section of the functional unit 5 can protrude into this gap. This section can carry a planar coil 41 which is short-circuited.

In the exemplary embodiment which is shown in FIG. 17, the voltage supply 9 consists of a power supply unit 30 which supplies a DC voltage which is voltage-limited by means of Zener diodes 32 . Via an inverter 26 , a trapezoidal AC voltage is generated with a frequency of approximately 200 kHz. This alternating voltage is supplied to the conductor tracks of the module carrier 4 via a jumper. A plurality of primary windings 20 of the separable transformer halves are located in parallel connection on the module carrier 4 (cf. FIG. 14). Each of these primary winding 20 is preceded by a ballast.

Form the secondary side of the transformer secondary individual coils 19 ', which via a choke 44 to a DC are connected upstream of rectifiers 30 which rectifier 30 and an individual galvanically isolated power sup ply forms for a circuit 25th

In the embodiment shown in FIG. 18, the primary windings 20 are connected in series. The rectifier 30 is a current limitation 42 nachgeord net. The current limit 42 is followed by an inverter 26 . Behind the inverter 26 is a current control 43 to readjust the current in the AC circuit on the module carrier 4 , so that enough current always flows through the primary windings 20 , regardless of how many modules 5 are plugged. In this circuit it is provided that at least a minimum current flows through a secondary coil.

Fig. 19 shows a circuit example of a two redundant power supplies, power supply. Each transmitter half assigned to the module carrier 4 has two galvanically isolated primary coils 20 , each of which is voltage-connected to a power supply unit 9 . In this technical solution, the two primary voltages can be phase locked, so that the effect of both primary windings add up. The amplitudes of the primary voltages can, but do not have to be of the same size. The phase angle of both primary voltages can be shifted against each other so that the effects are subtracted. If, for example, one power supply unit malfunctions and, for example, delivers full power, the second, properly operating power supply unit can compensate for the excess power. This also benefits explosion protection. Both primary and secondary windings can be designed as a planar coil.

The primary voltage applied can be sinusoidal. Operation with triangular or trapezoidal or rectangular voltages is also conceivable. As shown in FIG. 22, the individual pulses can have gaps in the pulse or changing pulse / pause ratios. In particular, it can be provided that - as shown in FIG. 21 - the one power supply unit delivers the positive half-wave and the other power supply unit the phase-shifted negative half-wave.

According to the ballast element 37 is integrated as a proper shaft of the magnetic plug contact ( Fig. 23). The magnetic plug contact can also be designed as shown in FIG. 16. In this version, it does not consist of a separable transformer that has a smaller air gap after closing than when it is open. The magnetic plug contact then consists of a transformer with a constant air gap. In this gap, a secondary winding in the form of a planar coil is inserted as part of the module board 5 when the module is inserted. In contrast to FIG. 16, the planar coil 41 is not a short-circuited coil, but rather the secondary coil 19 . Instead of the chokes or inductors connected in parallel to the primary winding, capacitors can also be connected in parallel as reactors to limit the current.

The embodiment shown in FIG. 23 shows schematically a development of a voltage supply for a module. In the supply voltage line on the module carrier 4 5 leads are switched for each slot of a module for the voltage supply of the respective module 5 . The power is supplied to the module 5 via electrical contacts, these electrical contacts being released when the module is removed. In order to avoid sparking when removing the module plug-in card 5 , a throttle 37 is individually connected in front of the plug contact. Thereafter, the throttle can be switched in one of the two supply lines, as well as in both supply lines ( Fig. 24). In the exemplary embodiment, the supply voltage is a square-wave voltage, so that the current flowing through the choke has a triangular shape ( FIG. 16).

Fig. 26 shows an embodiment of such a throttle 37th The throttle has a core consisting of two E-shaped core halves 39 . The two central core legs are spaced apart and form an air gap. The two outer core legs touch. All three core legs protrude through openings 45 in the circuit board of the module carrier. Only around the outer legs of the core 39 are the coil windings 38 of the throttle. The coil 38 is a planar coil and is formed by two spaced conductor tracks.

The circuit board 47 has a total of three insulating layers 48 ( Fig. 28). These form two outer insulating layers, each with a thickness of 1 mm and a central insulating layer with a thickness of 1/2 mm. The conductor tracks 46 are located between these insulating layers, which consist of epoxy.

During assembly, the first core halves 39 are glued to the circuit board using adhesive 51 in such a way that the legs of the core halves protrude through the openings 45 in the circuit board ( FIG. 29). Then the rear core halves 39 are glued against the end faces 52 of the outer legs. Fixation takes place by means of a U-shaped bar 49 which is placed over a plurality of cores 39 which are arranged one behind the other in rows. Such a U-shaped strip 49 lies on each side of the circuit board 47 . The strips 49 are connected to one another at both ends by means of fastening pins 50 , the fastening pins projecting through the circuit board ( FIG. 30).

Fig. 31 shows schematically a transformer which, for example. On a board of the module 5 or the module carrier 4 or the power supply can be mounted. Here, too, as shown in FIG. 33, the carrier of the core 55 of the transformer is the circuit board itself. The primary coil 54 and the secondary coil 56 are again formed here by conductor tracks of the circuit board. This transformer not only has the function of galvanically isolating the secondary side from the primary side or transforming the primary voltage to a secondary voltage. This transformer also has the function of a secondary or primary-side choke. This transmitter is preferably used on a module 5 in the manner shown in FIG. 17 or also in FIG. 18. The transformer is used to power the module. The core, which is composed of two core halves, has a substantially rectangular ring shape, the narrow legs 55 'of the core 55 of the primary winding 54 and the secondary winding 56 being assigned net. The longitudinal legs 55 "connect the two legs 55 'associated with the windings 55 , 56. The width B, ie the distance between the two legs 55 ' lying in the center of the coils 54 , 56 , is preferably greater than the height H, the Distance between the other two legs 55 ". This form of the transformer core and the coil arrangement has the result that the parasitic inductances shown in the He circuit diagram with 54 'and 56 ' become relatively large and thus have the effect of a choke.

FIG. 33 illustrates an embodiment in which the primary coil formed as planar coils 54 and secondary coil 56 do not overlap each other. An overlap of the primary coil 54 with the secondary coil 56 is also possible, but is not currently preferred. The leakage inductance can be in a range between 4 and 10% of the total inductance. A leakage inductance of 4% is preferred. However, it can also be greater than 10%.

In FIG. 34, a circuit is shown in wel cher a 300 kHz square wave voltage through a choke 37 and subsequent thereto plug contacts is transferred to a module 5. The plug contacts lead to the primary side of a transmitter, as shown in FIG. 33. The inductor inductor shown there with 56 'is a parasitic inductance and is caused by the magnetic shunt of the transformer consisting of the windings 54 and 56 . A rectifier 30 is connected to the secondary winding 56, which is limited in this way, with a filter capacitor 31 for providing an output direct voltage which is present at the output terminals.

The module carrier 4 is preferably supplied with voltage by two redundant power supply units 9 ( FIG. 34). Each power supply 9 can be designed as a plug-in card and can therefore be replaced. The redundancy of the two power supplies 9 has the consequence that the power supplies can be replaced during operation. The exchange of network cards should also be spark-free. For this purpose, the power transmission from the network card 9 to the module carrier 4 also takes place by means of a separate transformer, the primary winding 59 of which sits on the network card 9 and the secondary winding 57 of which sits on the module carrier 4 . For the design of such a transformer, reference is made to FIG. 4 and the associated description.

On the module carrier 4 , the two secondary windings 57 are connected in parallel to one another, but each with the interposition of a switch 58 ( FIG. 35). This switch 58 is only closed when a voltage is induced in the secondary coil 57 or when the network card 9 is inserted and the primary coil 59 is energized. In the circuit example shown in FIG. 36, the primary coil of an auxiliary transformer 60 is seated on the power supply 9 in series with the primary coil 59 . The connections of the secondary coil of this auxiliary transformer 60 are transmitted to a rectifier of the module carrier via conductive plug connections. A relay 61 , which actuates the switch 58 , is located behind the rectifier. The auxiliary transformer 60 is designed so that it delivers very little power, so that no sparks are generated when the conductive contacts to the module carrier 4 are released. If the connection is released, the relay 61 releases, the switch ter 58 opens and the coil 57 is open. The auxiliary transformer can also be designed as a separable transformer.

FIG. 37 shows an evaluation unit 62, which depart from the data lines in the form of a bus. One or more connection terminals 63 , which lie in the explosion-protected area, accesses these data lines. A power supply line runs parallel to the data bus and is fed by a power supply unit 9 . The connection terminal 63 taps the operating voltage from this power supply line. The decoupled energy is passed through a choke 44 . So that a throttled AC voltage can be coupled out of the connection terminal 63 . This is due to a connector strip, on which a plug of a field device 3 can be plugged.

The configuration of the choke 44 shown in FIG. 37, FIGS. 38 and 39. In the case shown in FIG. 38 depicted restrictor 44 is it is a ka pazitive throttle. In the two operating voltage supply lines, capacitors 23 and 24 are connected. The capacitors can have a value such that the reactance is between 50 and 1000 ohms. Capacitors between 1 nF and 10 nF are suitable as capacitors with an alternating voltage between 200 kHz and 300 kHz.

The choke 44 shown in FIG. 39 has a coil 33 . Alternatively, it can also be provided here that a further coil 33 is switched into the other operating voltage line parallel to the coil 33 . The inductances of the coils are preferably between 1 and 10 μH. A reactance can be between 1 and 20 ohms.

The supply voltage is preferably between 20 and 30 volts.

In FIG. 40, an inventive power supply is shown as it is used to supply a potentially explosive protected functional unit. The energy is extracted here via the coil 33 .

In the case shown in FIG. 41, the energy is coupled out by the two capacitors 23 and 24 .

The block diagram shown in FIG. 42 shows a power supply unit according to FIG. 40 or 41, as it is connected to a connection terminal 63 . The connection terminal 63 is line-connected to a field device 3 and supplies the field device 3 with the operating voltage provided by the power supply unit 9 or ensures data exchange between the field device 3 and an evaluation unit 62 . The power supply 9 can be located outside the explosion-protected area 8 .

In the circuit example shown in FIG. 43, there is a switch box 2 together with a host computer 1 outside the explosion-protected area 8 . A large number of connection terminals 63 are located in the switch box 2 . For the sake of clarity, only one connection terminal 63 is shown. The connection terminals can each be built on a separate circuit board. However, it is also possible for the connection terminals 63 to sit on a common circuit board. A throttle 44 is associated with the connection terminal 63 , as shown in FIGS. 38 and 39.

The reactor 44 is powered by a power supply 9 . The energy throttled as a result of the choke 44 is coupled out to a field device 3 . The field device 3 is in the explosion-protected area.

All the features disclosed are essential to the invention. In the disclosure of the application is hereby also the Disclosure content of the associated / attached priori full documents (copy of the pre-registration) Lich included, also for the purpose of characteristics of this  Documents in claims of the present registration with to record.

Claims (50)

1. Device for power supply nine explosion-protected functional units, characterized in that the energy decoupling is inductively ( 33 , 44 , 53 ) or capacitive ( 23 , 24 , 29 ) throttled. 2. Apparatus according to claim 1 or in particular since, characterized in that the choke ( 23 , 24 , 29 , 33 , 44 , 53 ) is formed by a reactance which is between 1 and 1000 ohms. 3. Device according to one or more of the preceding the claims or in particular according thereto, thereby records that the output voltage has a frequency between between 200 and 300 kHz. 4. Device according to one or more of the preceding the claims or in particular according thereto, thereby records that the decoupling inductance has a value has between 1 and 10 µH. 5. Device according to one or more of the preceding the claims or in particular according thereto, thereby records that the decoupling capacity has a value has between 1 and 10 nF. 6. Device according to one or more of the preceding the claims, characterized by one of each switched on both power supply output lines th inductors in the form of a coil or a condenser sators. 7. Device for supplying a large number of electronic functional units that can be assigned to a common carrier, in particular can be plugged on, in a potentially explosive area from at least one operating voltage source ( 9 ), characterized in that the operating voltage is an AC voltage and functional unit ( 5 ) and carrier ( 4 ) or Be the operating voltage source ( 9 ) and the carrier ( 4 ) each have a part ( 11 , 15 ) of a separable inductive transformer. 8. The device according to claim 7 or in particular since, characterized in that the carrier ( 4 ) associated parts ( 15 ) of the transformer either Stromge controls in series or individually connected in parallel. 9. Apparatus according to claim 8 or in particular since, characterized in that the element ( 37 ) upstream of each coil ( 20 ) of a transformer part ( 15 ) connected in series is influenced by the insertion of the functional unit ( 5 ). 10. The device according to one or more of the preceding claims or in particular according thereto, characterized in that the electrically parallel-connected coils ( 20 ) are connected in series with a magnetic switch (reed contact) which closes when the assigned functional unit is inserted. 11. The device according to one or more of the preceding claims or in particular according thereto, characterized in that the coils ( 20 ) each have a Dros sel upstream. 12. The device according to one or more of the preceding claims or in particular according thereto, characterized in that the core ( 39 ) of the throttle ( 33 , 37 , 44 ) is formed from a material drivable by a magnetic field into the saturation and the functional unit ( 5 ) carries a magnet ( 40 ). 13. The device according to one or more of the preceding claims or in particular according thereto, characterized in that the core ( 39 ) of the throttle ( 33 , 37 , 44 ) has a gap for inserting a short-circuit coil ( 41 ) of the functional unit ( 5 ) . 14. The device according to one or more of the preceding claims or in particular according thereto, characterized in that the coil ( 41 ) is designed as a planar coil. 15. The device according to one or more of the preceding claims or in particular according thereto, characterized by a two power supply units ( 9 ) consisting of operating voltage source, each power supply unit feeding a primary coil to each of the module carriers assigned to the carrier. 16. Device according to one or more of the preceding existing claims or in particular according thereto, thereby characterized in that the power control over the Phase position of the two AC voltages takes place. 17. Device according to one or more of the preceding existing claims or in particular according thereto, thereby characterized in that the power control over the Addition or subtraction of the amplitudes of the two AC voltages occur.   18. Device according to one or more of the preceding existing claims or in particular according thereto, thereby characterized in that the one transformer part a Wick lung and has a core with a gap and the other Transformer part a coil that can be inserted into the gap. 19. Device for signal conversion between in a potentially explosive area ( 8 ), in particular special analog signals via a signal line ( 6 ) receiving and / or transmitting actuators or sensors ( 3 ) and a particular digital data via a data line ( 7 ) receiving and / or transmitting master computer ( 1 ) of a signal transmission system, in particular a field bus system

• a) an operating voltage supply ( 9 ),
• b) a module carrier ( 4 ),
• c) one or a plurality of modules ( 5 ) which can be plugged onto or removed from the module carrier ( 4 ) during operation of the fieldbus system,
• d) a detachable operating voltage connection ( 11 , 15 ) between module carrier ( 4 ) and module ( 5 ) when the module ( 5 ) is removed,
• e) a data transmission connection ( 10 , 14 ; 12 , 16 ) that can be released when the module ( 5 ) is removed between module carrier ( 4 ) and module ( 5 ),

characterized in that

• a) the operating voltage supply on the module carrier ( 4 ) is an AC voltage and
• b) the operating voltage connection ( 11 , 15 ) is essentially spark-free separable.

20. The apparatus of claim 12 or in particular there according to, characterized in that the modules with a AC voltage are powered. 21. The device according to one or more of the preceding claims or in particular according thereto, characterized in that the operating voltage connection ( 11 , 15 ) is formed by a separable, inductive transformer. 22. The device according to one or more of the preceding claims or in particular according thereto, characterized in that the separable transformer he ste, firmly connected to the module carrier ( 4 ), a primary winding ( 20 ) receiving core half ( 18 ) and a second, fixed with the module ( 5 ) connected, a secondary winding ( 19 ) having core half ( 17 ). 23. The device according to one or more of the preceding claims or in particular according thereto, characterized in that the primary winding consists of two half-windings ( 20 '), the half-winding ( 20 ') each of the primary core halves lying side by side ( 18 ) individually in series are switched and the half-windings ( 20 ') of the last primary core half ( 18 ) of the series are connected to one another. 24. The device according to one or more of the preceding claims or in particular according thereto, characterized in that the secondary windings forms a large number of galvanically isolated individual windings ( 19 '). 25. Device according to one or more of the preceding existing claims or in particular according thereto, thereby characterized in that the primary voltage be about 1 volt carries and the secondary voltage is about 30 volts. 26. Device according to one or more of the preceding existing claims or in particular according thereto, thereby characterized in that the AC voltage is a high frequency voltage of preferably between 200 and 300 kHz is. 27. Device according to one or more of the preceding existing claims or in particular, characterized net through an individually assigned module Power limitation in the form of a reactance in an AC circuit. 28. The device according to one or more of the preceding claims or in particular according thereto, characterized in that the reactance is in the circuit of the secondary winding ( 19 ). 29. Device according to one or more of the preceding existing claims or in particular according thereto, thereby characterized that the operating AC voltage off a DC voltage is obtained. 30. The device according to one or more of the preceding claims or in particular according thereto, characterized in that the two voltage supply lines each have a capacitor ( 23 , 24 ) or a choke ( 44 ) for power limitation. 31. The device according to one or more of the preceding claims or in particular according thereto, characterized in that the modules ( 5 ) are electrical scarf device carrier. 32. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the modules ( 5 ) are plug elements. 33. Device according to one or more of the preceding existing claims or in particular according thereto, thereby characterized in that the operating voltage on the Modu len is rectified. 34. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the operating voltage connection between an operating voltage supplying power supply unit ( 9 ) and the module ( 5 ) via electrically conductive de, separable contacts and the power supply side contacts a choke ( 37 ) is connected upstream. 35. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the respective chokes assigned to a module slot ( 37 ) sit on the module carrier board and are designed as planar coils, the respective coil ( 38 ) essentially only the two outer legs of the particular E-shaped coil core ( 39 ) is assigned, which leg openings ( 45 ) pass through the board. 36. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the coil ( 38 ) is ausgebil det from a fully isolated conductor track of a multilayer board. 37. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the coil cores ( 39 ) arranged in a row are caught and held by a U-shaped strip ( 49 ). 38. Device according to one or more of the preceding claims or in particular according thereto, characterized in that one of the two core halves of the core ( 39 ) is adhesively bonded to the circuit board ( 51 ) and both cores are each held by a strip ( 49 ), which by a connecting element ( 50 ) penetrating the circuit board is connected to one another. 39. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the parameters of the choke ( 37 ), for example, core material, coil diameter and number of turns are selected so that the permeability over the entire modulation of the operating voltage supply is substantially constant in temperature . 40. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the effect of the choke ( 53 ) serving for power limitation is provided by a transformer ( 54 , 56 , 56 ') with a magnetic shunt. 41. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the leakage inductance of the transmitter ( 53 ) is at least 4 to 10% of the total inductance. 42. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the core ( 55 ) of the transformer ( 53 ) consists of two elongated U-core halves. 43. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the two spatially separated windings (54 and 56) having core legs 'are spaced further apart than the said legs (55 (55)') to each other connecting leg ( 55 '') of the substantially rectangular-ring-shaped core. 44. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the coils ( 54 and 56 ) are possibly partially overlapping planar coils. 45. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the supply voltage of the two power supplies ( 9 ) by means of a separable transformer ( 59 , 57 ) is fed to the carrier ( 4 ), the secondary coil ( 57 ) of the transformer is assigned to the carrier ( 4 ) and the primary coil ( 59 ) of the power supply board, the secondary coil ( 57 ) being connected to the secondary circuit only when the power supply unit is plugged in and supplies voltage. 46. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the scarf sitting on the support ter ( 58 ) for switching the secondary coil in the secondary circuit is assigned to a relay ( 61 ), which of a in the primary circuit the power supply ( 9 ) switched auxiliary transformer is energized. 47. Device according to one or more of the preceding claims or in particular according thereto, characterized in that a plurality of secondary windings ( 57 ) respectively associated power supplies ( 9 ) are connected in parallel on the carrier ( 4 ). 48. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the secondary windings ( 57 ) respectively associated power supplies ( 9 ) are connected in series on the carrier ( 4 ). 49. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the throttle ( 44 ) is assigned to a connection terminal arranged in the explosion-protected area for at least one field device 3 . 50. Device according to one or more of the preceding claims or in particular according thereto, characterized in that the throttle ( 44 ) is arranged in a non-explosive area arranged switch box ( 2 ) net.