ETHERCAT BUS SYSTEM, HAVING AN ETHERCAT BUS MASTER AND ETHERCAT BUS DEVELOPER

Description

[0001] The invention relates to an ETHERCAT bus system comprising an ETHERCAT bus master and ETHERCAT bus subscribers.

[0002] DE 10 2017 214 893 A1 discloses a method for operating an ETHERCAT fieldbus system which has a computer as bus master.

[0003] A bus system is known from US 2014 / 0 047 056 A1. Thus, during production, a suitable bus master must be kept in stock for each distributor, then selected and assembled.

[0004] From the EP 2 688 250 A1 The closest state of the art is a network system.

[0005] From the WO 2012 / 087901 A2 is a communication architecture for data communication.

[0006] From the EP 2 688 002 A1 Known as an assistance system for network design.

[0007] The invention is therefore based on the object of enabling star-shaped connected strands to be flexibly formed in ETHERCAT.

[0008] According to the invention, the object is achieved in the bus system according to the features specified in claim 1.

[0009] Important features of the invention in the ETHERCAT bus system are that it has an ETHERCAT bus master and ETHERCAT bus subscribers, wherein an ETHERCAT star distributor is arranged and / or populated together with the ETHERCAT bus master on the same printed circuit board.

[0010] The advantage is that the star topology can be implemented directly on the circuit board, allowing it to be implemented in real time. Furthermore, the configuration is interference-free. Furthermore, the voltage can be refreshed. The integrated design on a single circuit board enables a real-time implementation of the ETHERCAT bus.

[0011] Flexibility is ensured by the design on a single circuit board, as the PCB assembly can be configured flexibly. Different assembly configurations can be implemented as needed. This allows for the desired star distributor and bus master configuration to be installed. This eliminates the need for increased inventory.

[0012] In an advantageous embodiment, a level converter is arranged at the connection, in particular the output, of the bus master. From this level converter, data lines lead via at least one capacitive isolation, in particular a capacitor arrangement, to another level converter, which is arranged and / or connected to the connection of the star distributor. This is advantageous because, despite the arrangement on the same circuit board and thus the short distance between the bus master and the star distributor, level conversion and level reconversion are implemented with intermediate galvanic isolation.

[0013] In an advantageous embodiment, the star distributor has outputs, with a respective further level converter being arranged and / or connected to each output, each of which is connected via galvanic isolation to a respective connector part mounted on the circuit board, with a respective strand of bus devices connected in series via the ETHERCAT data bus being connectable, in particular connected, to the respective connector part. It is advantageous here that level converters are also provided, so that the star distributor itself can be implemented in TTL logic. This enables voltage refreshment in the star distributor in a simple manner.

[0014] According to the inventionThe circuit board is enclosed in a housing, with a heat sink dissipating the heat loss from the bus master and the star distributor to the environment. The advantage here is that a common housing is required for the circuit board, bus master, and star distributor.

[0015] In an advantageous embodiment, the bus master is connected to an Ethernet interface, which is also located on the circuit board. This is advantageous because information transmitted via ETHERCAT can be further transmitted via Ethernet.

[0016] According to the inventionThe Ethernet interface is located closer to the bus master than the star splitter is to the bus master, or the Ethernet interface is located closer to the star splitter than the bus master is to the star splitter. The advantage of this is that no interference is caused, even though the Ethernet interface can be located very close and thus emits interference. However, since level conversion, galvanic isolation, differential data lines, and voltage refresh are provided, the interference is manageable.

[0017] In an advantageous embodiment, the bus master is implemented as a single component, in particular an IC (integrated circuit), which is mounted on the circuit board. This is advantageous because an integrated design is achievable, allowing high data streams to be transmitted error-free or at least with minimal errors.

[0018] In an advantageous embodiment, the star distributor is designed as a single component, in particular an IC (integrated circuit), which is mounted on the printed circuit board. This allows for a compact design, which allows for mass production and thus requires low costs per component.

[0019] In an advantageous embodiment, the bus master is connected to an Ethernet interface, which is also arranged and / or mounted on the circuit board. This allows for simple, compact manufacturing.

[0020] Further advantages emerge from the dependent claims. The invention is not limited to the combination of features in the claims. Further possible combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent to those skilled in the art, particularly from the problem and / or the problem posed by comparison with the prior art.

[0021] The invention will now be explained in more detail with the aid of schematic illustrations: In the Figure 1 A system according to the invention is shown schematically.

[0022] In this case, a controller 1 is mounted on a preferably one-piece, i.e. one-part, printed circuit board 8, which controller has an Ethernet interface and is also connected to a bus master 2 mounted on the printed circuit board 8 for data transmission.

[0023] For data transmission, the bus master 2 has a connection which is connected via a level converter 3 and a differential data line as well as a capacitive decoupling 9 to a further level converter which is arranged at a connection of a star distributor 5.

[0024] Thus, after the voltage levels have been converted by the level converter 3, the bus master signals are routed via the differentially designed data lines to a capacitor arrangement that provides galvanic isolation. DC voltages cannot be passed from the level converter 3 connected to the bus master 2 terminal to the level converter 3 connected to the star distributor 5 terminal.

[0025] The voltage level of the AC voltage components passing through the capacitor array is converted by the level converter 3 and fed to the star distributor 5, preferably as a TTL level. The bus master can also be operated using a TTL level, so that only the differential data line has a different level.

[0026] The bus master is an ETHERCAT bus master, and the star splitter is also an ETHERCAT star splitter. In particular, the signals coming from the bus master 2 are fed to the other connections of the star splitter 5, whose signals are fed to a respective level converter 3 and, in turn, routed as differential signals via a respective galvanic decoupling 4 to connector parts 6 mounted on the circuit board 8.

[0027] A plurality of bus participants 7 designed as ETHERCAT bus participants form a serially connected respective strand, which is each connected to the respective connector 6.

[0028] Several lines can be connected to the star distributor 5. In Figure 1 three strands are connected here.

[0029] Since the star distributor 5 and the bus master 2 are mounted on the same circuit board, only a single housing is required for the star distributor 5 and the bus master 2. Furthermore, heat dissipation can be achieved through a single heat sink, which dissipates the heat loss of the star distributor 5 and the heat loss of the bus master 2 to the environment.

[0030] Since the incoming and outgoing data lines at the star distributor 5 are galvanically decoupled, a voltage refresh within the star distributor 5 can be carried out in further embodiments according to the invention.

[0031] Although bus master 2 and star splitter 5 are arranged on the same circuit board 8, level converters 3 and galvanic decoupling, particularly capacitive isolation, are provided. Thus, other signal electronics components can be arranged on the circuit board, whose electromagnetic radiation would be disruptive. However, since the galvanic isolation and level conversion reduce the negative effects of interference, these other signal electronics components can be arranged very close to the ETHERCAT components, particularly bus master 2 and star splitter 5.

[0032] Another such signal electronics component is, for example, the Ethernet interface. Thus, this interface can also be arranged very close to the bus master 2 or the star junction 5. In particular, the Ethernet interface is arranged closer to the bus master than the star junction is from the bus master, or the Ethernet interface is arranged closer to the star junction than the bus master is from the star junction.

[0033] Preferably, the bus master 2 is designed as ETHERCAT bus master 2 and the bus participants 7 as ETHERCAT bus participants 7. In addition, the star distributor 5 is designed as a distributor for ETHERCAT. List of reference symbols

[0034] 1 Controller 2 Bus master 3 Level converter 4 Galvanic isolation 5 Star distributor 6 Connection, especially connector 7 Bus device 8 Circuit board 9 Capacitive isolation

Claims

1. EtherCAT bus system comprising an EtherCAT bus master (2) and EtherCAT bus subscribers (7), characterised in that an EtherCAT star hub (5) is arranged and / or mounted on the same printed circuit board (8) together with the EtherCAT bus master (2), the printed circuit board (8) being surrounded by a housing, the cooling member dissipating the thermal losses of the bus master (2) and the star hub (5) to the surroundings, the housing acting as a single housing for the star hub (5) and the bus master (2), a single cooling member dissipating the thermal losses of the star hub (5) and the thermal losses of the bus master (2) to the surroundings, the bus master (2) being connected to an Ethernet interface, which emits interfering radiation and is likewise arranged on the printed circuit board (8), the Ethernet interface being less distant from the bus master than the star hub is distant from the bus master, or the Ethernet interface being less distant from the star hub than the bus master is distant from the star hub, level conversion, galvanic isolation, differential data routing and voltage refresh being implemented.

2. Bus system according to claim 1, characterised in that at the terminal (6), in particular the output, of the bus master (2) there is arranged a level converter (3), from which data lines lead to a further level converter (3) via at least one capacitive isolation (9), in particular a capacitor arrangement, said further level converter being arranged at and / or connected to the terminal (6) of the star hub (5).

3. Bus system according to any of the preceding claims, characterised in that the star hub (5) comprises outputs, a respective further level converter (3) being arranged at and / or connected to each output, said further level converters each being connected, via a galvanic isolation (9), to a respective plug connector part mounted on the printed circuit board (8), a chain of bus subscribers (7) that are connected in series by means of the EtherCAT data bus being connectable, in particular connected, to each plug connector part.

4. Bus system according to any of the preceding claims, characterised in that the bus master (2) is configured as a single component, in particular an IC, i.e. an integrated circuit, and in particular is mounted on the printed circuit board (8).

5. Bus system according to any of the preceding claims, characterised in that the star hub (5) is configured as a single component, in particular an IC, i.e. an integrated circuit, and in particular is mounted on the printed circuit board (8).