EP2591974A2

EP2591974A2 - Information transmission device and information transmission method

Info

Publication number: EP2591974A2
Application number: EP20120191372
Authority: EP
Inventors: Yoshinori Okura; Yutaka Sato; Koichi Nakanishi
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 2011-11-09
Filing date: 2012-11-06
Publication date: 2013-05-15
Also published as: JP5520917B2; JP2013102624A; CN103108058A

Abstract

An information transmission method and device in which a device can determine and automatically set information such as IP address based on position information and arrangement order that are detected is provided. When new position information and information about arrangement order are needed, each data processing device transmits position confirmation data to a branch transmission line. The position confirmation data includes information designating a transmission direction to a main transmission line or the branch transmission line. When a relay device receives the position confirmation data, the relay device relays the position confirmation data to a predetermined direction. Each data processing device determines the position information and information about arrangement order of the own device and the like, based on the number, data content and the like of the position confirmation data received from the relay device.

Description

BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION

The present invention relates to an information transmission system installed in railway cars.

DESCRIPTION OF THE RELATED ART

With respect to railway cars, the number of cars and the arrangement order of cars within a train set may dynamically change, for example, plural train sets are coupled and travel as a single train set or a single train set is split into plural train sets to travel.
Meanwhile, in an information transmission system installed in railway cars, some of parameters that are necessary for a transmission device constituting the information transmission system to transmit and receive data or to relay data may be set in accordance with the number of cars and the arrangement order of cars within the train set. An example of such parameters is IP (Internet Protocol) address. If information about what ordinal number the car is from the first car or about the car number is included in a bit string of an IP address, the positional relation of a transmission destination within the train set is made clear simply by referring to the IP address of the transmission destination without having to analyze the content of data. Thus, processing load related to transmission, reception and relay of data is reduced.
However, if the number of cars and the arrangement order of cars within the train set dynamically change, the arrangement order of individual transmission devices within the train set changes, too. Therefore, allocated IP addresses must be changed accordingly.
As a technique for reallocating IP addresses in accordance with a change in the number of cars or the arrangement order of cars within the train set, for example, a railway car network system described in JP-A-2005-175904 is known.
This system employs TCP (Transmission Control Protocol)/IP or UDP (User Datagram Protocol)/IP as a transmission protocol. A train set identification number and a transmission device identification number are allocated to the third byte and the fourth byte of an IP address. The IP addresses of transmission devices in the first car and the last car or in the end cars coupled to each other of different train sets are fixed. Thus, even when the number of cars within a train set is increased or decreased, the IP addresses of the other transmission devices are allocated with reference to the transmission devices having the fixed IP addresses.
In the technique described in JP-A-2005-175904 , the IP addresses of the transmission devices in the first car and the last car or in the end cars coupled to each other of different train sets are fixed, or position information within the train set of the cars where a transmission device is installed (the first car or the last car, or the end cars coupled to each other of different train sets) is reported from a car equipment, and IP addresses are automatically set based on the information.
In the case where the IP addresses are fixed, the IP addresses need to be preset before the transmission device is installed in the cars, or work of setting the IP addresses using a setting switch (DIP switch, rotary switch or the like) and a setting terminal or the like is necessary after the installation in the cars. However, in the technique in which the IP addresses are preset before the transmission device is installed in the cars, a transmission device for another car cannot be used to replace the device when a failure occurs, and a device for replacement needs to be prepared for each car. Therefore, there is a problem of high cost. Meanwhile, in the technique in which the IP address is set after the installation in the cars, the amount of work increases at the time of installation in the cars and therefore there is a problem that a setting error may occur.
Also, in the case where the IP addresses are automatically set by the above techniques, a function or device to notify a transmission device of the position information within the train set of the cars where the transmission device is installed (the first car or the last car, or the end cars coupled to each other of different train sets) is necessary on the car side. Therefore, there is a problem that the number of devices and the number of components increase.
Moreover, there are similar problems to the above with other devices installed in the cars as well as the transmission device.

SUMMARY OF THE INVENTION

Thus, the invention provides an information transmission method and device in which with respect to not only a transmission device but also other devices installed in cars, presetting or notification of position information within a train set of cars where the device is installed is not necessary before the device is installed in the cars, and in which the position information and the arrangement order within the train set of the cars where the device is installed can be detected by mutual exchange of information between plural devices. Moreover, an object of the invention is to provide an information transmission method and device in which the devices can determine and automatically set information such as IP address based on the detected position information and arrangement order.
To solve the foregoing problems, according to an aspect of the invention, an information transmission device for a railway car for transmitting data between railway cars of a train set made up of plural railway cars includes: a relay device which is connected with a relay device of a next car via a main transmission line and carries out relay processing of data received from the next car; and a data processing device connected with the relay device via a branch transmission line. When the data processing device outputs data including information of a transmission direction to the relay device, the relay device has a unit which decides a relay direction of the data in accordance with the information of the transmission direction included in the data received from the branch transmission line or the main transmission line. The data processing device detects a position of own device in the train set from the data received from the relay device.
Also, in an information transmission method, a relay device which is connected with a relay device installed in a next car via a main transmission line and carries out relay processing of data received from the next car, and a data processing device connected with the relay device via a branch transmission line are provided, and data is transmitted between railway cars of a train set made up of plural railway cars. The method includes: a step in which data including information of a transmission direction is outputted from the data processing device to the relay device; a step in which the relay device, receiving the data, decides a relay direction of the data in accordance with the information of the transmission direction included in the data; and a step in which the data processing device, receiving the data, detects a position of own device in the train set in accordance with the number of times the data is received.
According to the invention, presetting or notification of the position information within the train set of the cars where the device is installed is not necessary before the device is installed in the cars. Therefore, a device for another car can be used without changing the setting to replace the device when a failure occurs. Also, since the work of setting the position information and the arrangement order using a setting switch (DIP switch, rotary switch or the like) and a setting terminal or the like is not needed after the installation in the cars, no setting error occurs.
Also, even though the position information within the train set of the cars where the device is installed is not preset or notified of, simply by mutual exchange of information between plural devices, the device can detect the position information and the arrangement order of the car within the train set, and information such as IP address can be determined and automatically set in the device based on the detected position information and arrangement order. Therefore, cases where the car configuration within the train set dynamically changes, such as where plural train sets are coupled or a train set is split into plural train sets, can be dealt with.
Moreover, even when a car where the device is installed is changed to a different car or a car in a different train set, work of adding or changing the setting of the device need not be carried out and the device can carry out an operation corresponding to the installation position after change.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the configuration of an information transmission system according to an embodiment of the invention.
FIG. 2 shows the configuration of a relay device according to an embodiment of the invention.
FIG. 3 shows a detection flow according to an embodiment of the invention.
FIG. 4 shows an operation according to an embodiment of the invention.
FIG. 5 shows a detection flow according to an embodiment of the invention.
FIG. 6 shows an operation according to an embodiment of the invention.
FIG. 7 shows the configuration of an information transmission system according to an embodiment of the invention.
FIG. 8 shows the configuration of an information transmissions system according to an embodiment of the invention.
FIG. 9 shows the configuration of an information transmission system according to an embodiment of the invention.
FIG. 10 shows the configuration of an information transmission system according to an embodiment of the invention.
FIG. 11 shows the configuration of a data relay unit according to an embodiment of the invention.
FIG. 12 shows the configuration of an information transmission system according to an embodiment of the invention.
FIG. 13 shows the configuration of a display device according to an embodiment of the invention.
FIG. 14 shows the configuration of an information transmission system according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In embodiments of the invention, a relay device and a data processing device need not have, in advance, position information in the train set of the car where the own device is installed, such as car number, and information about the arrangement order relative to other data processing devices. When new position information or information about a new arrangement order is needed, for example, when power is switched on or reset is carried out, or when the train set configuration is changed by coupling of or splitting into plural train sets, each data processing device transmits position confirmation data to a branch transmission line.
The position confirmation data includes information designating a transmission direction to a main transmission line or branch transmission line. The information designating the transmission direction included in the position confirmation data transmitted by all the data processing devices is the same. When plural types of data processing device with different operations or functions coexist, different information may be defined for each of the types, as the information designating the transmission direction.
Each relay device decides in advance the correspondence between the information designating the transmission direction included in the position confirmation data and the direction in which the position confirmation data is relayed such as the main transmission line or the branch transmission line. When the relay device receives the position confirmation data, the relay device relays the position confirmation data in the direction that is decided in advance. The correspondence is the same for all the relay devices and the result is the same whichever car the relay device is connected to.
Each data processing device determines the position information of the own device, the information about the arrangement order and the like, based on the number of position confirmation data and the data contents received from the relay device.
Hereinafter, detailed embodiments of the invention will be described with reference to the drawings.

First Embodiment

A first embodiment will be described.
First, FIG. 1 shows an example of configuration of an information transmission system according to the first embodiment.
In the information transmission system shown in FIG. 1, a train set is made up of plural cars 1. Each car 1 includes a relay device 2 for transmitting and receiving or relaying data between cars, a main transmission line 9 connecting the relay device 2 of each car, a data processing device 990 which is installed in each car and controls train traveling functions such as electric motor and brake, or controls other functions than the train traveling functions such as air conditioning and interior lights, and a branch transmission line 99 connecting the relay device 2 and the data processing device 990.
FIG. 2 shows the configuration of the relay device 2. The relay device 2 shown in FIG. 2 includes a data relay unit 3 and a data distribution unit 4.
The data relay unit 3 has a function of carrying out processing to relay data received from one side of the main transmission line 9 to the other side of the main transmission line 9, send to the data distribution unit 4 data to be relayed from the main transmission line 9 to the branch transmission line 99, and relay data received from the branch transmission line 99 via the data distribution unit 4 to the main transmission line 9, or the like.
The data relay unit 3 also stores "destination information" indicating the destination of data such as a destination address in association with information indicating the main transmission line and the branch transmission line of the relay destination. For example, as shown in FIG. 2, ports of transmission lines held by the data relay unit 3 are numbered (1), (2) and (3), and information that data with destination information "A" should be relayed only to the ports (1) and (2) whereas data with destination information "B" should be relayed only the ports (2) and (3), or the like is stored.
The data distribution unit 4 is a part of the branch transmission line 99 and has a function of connecting plural data processing devices 990 to the relay device 2.
In this embodiment, as an example, it is assumed that the data relay unit 3 uses a switching hub or layer-3 switch that is used in a LAN conforming to the IEEE 802.3 standard, and that an IP address or MAC address is used as the destination information. It is also assumed that a function is provided that enables fixed setting of a specific destination address and a relay destination port. Such a function can be realized, for example, by using a static MAC address setting function installed in KS8995MA, which is a switching device made by MICREL INC.
Also, the following explanation is based on the assumption that a LAN conforming to the IEEE 802.3 standard is used for the main transmission line 9 and the branch transmission line 99 and that a switching hub or repeater hub used in a LAN conforming to the IEEE 802.3 standard is used for the data distribution unit 4.
In the following explanation and drawings, in order to simplify the explanation, only one data processing device 990 connected to the relay device 2 is described and the explanation and representation of the other data processing devices 990 are left out.
Also, it suffices that the data distribution unit 4 at least has a function of connecting the data relay unit 3 to plural data processing devices 990 and relaying data between these units without altering the data. Therefore, the data distribution unit 4 is considered to be a part of the branch transmission line 99 hereinafter.
Next, procedures for the data processing device 990 to detect the position information and arrangement order of the own device will be described with reference to FIGS. 3 and 4.
When an event that serves as a trigger that causes the data processing device 990 to start detecting the position and arrangement order occurs, such as turning power on to the car 1, resetting the device, or change in the number of cars or the arrangement order of the cars 1 in the train set due to splitting or coupling of the train set (detection procedure 9001), each data processing device 990 transmits a position confirmation packet 301 including information designating a transmission direction to the main transmission line or the branch transmission line, that is, a destination IP address "239.0.0.1" (with a destination MAC address "01-00-5E-00-00-01") as shown in FIG. 4, to the branch transmission line 99 (detection procedure 9002). Here, the internal data of the packet may have an arbitrary value.
Meanwhile, all the relay devices 2 installed in each car 1 are set to relay the information designating the transmission direction to the main transmission line or the branch transmission line, that is, the packet including the destination IP address "239.0.0.1" (with the destination MAC address "01-00-5E-00-00-01") as shown in FIG. 4, to the ports (2) and (3). That is, it means that when the packet with the destination IP address "239.0.0.1" is received from the port (1), the packet is relayed to the ports (2) and (3), whereas when the packet is received from the port (2), the packet is relayed only to the port (3), and when the packet is received from the port (3), the packet is relayed only to the port (2). In the following description, the ports (1), (2) and (3) of the relay device 2 as shown in FIG. 4 are considered synonymous with the ports (1), (2) and (3) of the data relay unit shown in FIG. 2. Also, the destination IP address "239.0.0.1" (with the destination MAC address "01-00-5E-00-00-01") is an example in this embodiment and other values may also be used.
The relay device 2, receiving the position confirmation packet 301 from the branch transmission line 99, that is, from the port (3), relays the packet only to the port (2) of the main transmission line 9 because the destination IP address is "239.0.0.1". The position confirmation packet 301 reaches the port (1) of a next relay device 2.
Next, when the next relay device 2 receives the position confirmation packet 301 from the port (1) of the main transmission line 9, the next relay device 2 relays the packet to the port (2) of the main transmission line 9 and the port (3) of the branch transmission line 99 because the destination IP address is"239.0.0.1".
The position confirmation packet 301 transmitted to the branch transmission line 99 is received by the data processing device 990. The data processing device 990 recognizes the packet as the position confirmation packet 301 because the destination IP address is"239.0.0.1" and increments the number of the position confirmation packets 301 received, by one ( detection procedures 9003, 9004, 9005).
The data processing device 990 measures time from a certain time point after the occurrence of the event serving as the trigger. After the lapse of a predetermined time period (detection procedure 9006), the data processing device 990 detects the number of the received position confirmation packets 301 and determines the position and arrangement order of the own device (the value of P in detection procedure 9007).
In the example of FIG. 4, if four data processing devices 990 are named a, b, c and d from the first car (the end car in the direction of the port (1) of the relay device 2), the data processing devices 990 of a, b, c and d respectively transmit the position confirmation packet 301, and after that, the data processing device a receives no position confirmation packet 301 (P=0 in FIG. 3), the data processing device b receives one position confirmation packet 301 (P=1 in FIG. 3), the data processing device c receives two position confirmation packets 301 (P=2 in FIG. 3), and the data processing device d receives three position confirmation packets 301 (P=3 in FIG. 3). That is, each data processing device 990 can determine that the own device is the device at the (P+1)th position from the first car (the arrangement order is the (P+1)th). Also, the data processing device a of P=0 can be determined as the first car.
Based on this result, the data processing device 990 can set a setting value, for example, IP address or the like, corresponding to the position and arrangement order.
Also, whether correct setting is done or not may be checked by making such an arrangement that the information of the position and arrangement order detected by the above procedures, for example, the values of P or P+1, can be displayed on a display unit such as a light emitting diode (LED) or liquid crystal display unit (LCD) mounted on each data processing device 990 which detects the information, and allowing a maintenance worker of the data processing device 990 to view the display unit from outside.
Although an example in which a LAN conforming to the IEEE 802.3 standard is used for the main transmission line 9 and the branch transmission line 99 is described above, the main transmission line 9 and the branch transmission line 99 are not limited to the LAN conforming to the IEEE 802.3 standard and can be realized by other communication measures, for example, a LAN conforming to the ATM (Asynchronous Transfer Mode) or IEEE 802.5 standard, a field LAN conforming to the IEC 61158 standard or the like.
This also applies to all the following embodiments.
Moreover, while an example in which a switching hub or layer-3 switch used in a LAN conforming to the IEEE 802.3 standard is used for the data relay unit 3 is described above, the data relay unit 3 can also be realized with a configuration as shown in FIG. 11.
That is, in FIG. 11, the data relay unit 3 includes: an arithmetic device 2000 which is equipped with a CPU, a cache memory, a main storage memory or the like and which carries out relay processing of data; a storage device 2003 such as a hard disk, silicon disc or non-volatile memory which stores transmission and reception data, a processing program, initial setting information, log information or the like; a main transmission line interface device 2001 having an interface function for data transmission to and reception from the data relay unit 3 of the counterpart relay device 2 via the main transmission line 9; and a branch transmission line interface device 2002 having an interface function for data transmission to and reception from the data processing device 990 via the branch transmission line 99. The data relay unit 3 may also include, if necessary, an input device 2004 such as a switch or keyboard to input initial setting items like the address and the operation mode of the transmission line, and an output device 2005 such as a light emitting diode (LED) or liquid crystal display unit (LCD) which allows confirmation of the setting items and displays the operation state and log information.
In the case of the data relay unit 3 shown in FIG. 11, the destination information is not limited to destination address. A field indicating the destination information may be provided in a data field.
The arithmetic device 2000 determines the transmission line to which data should be relayed, based on the destination information of the data received from the main transmission line interface device 2001 or the branch transmission line interface device 2002, and outputs the data to one or both of the main transmission line interface device 2001 and the branch transmission line interface device 2002.
This, too, applies to all the following embodiments.
Up to this point, the first embodiment is described.
According to the above embodiment of the invention, position information within a train set of a car where a device is installed need not be preset or notified of before the device is installed in the car. Therefore, a device for another car can be used without changing the setting to replace the device when a failure occurs. Also, work of setting the position information and arrangement order using a setting switch (DIP switch, rotary switch or the like) and a setting terminal or the like is not necessary after the installation in the car. Therefore, setting errors do not occur.
Moreover, even though the position information within the train set of the car where the device is installed is not preset or notified of, the position information and the arrangement order within the train set of the car where the device is installed can be detected by mutual exchange of information between plural devices, and information such as IP address can be determined and automatically set in the device based on the detected position information and arrangement order. Therefore, cases where the car configuration within the train set dynamically changes, such as where plural train sets are coupled or a train set is split into plural train sets, can be dealt with.
Also, even when the car where the device is installed is changed to a different car or a car in a different train set, work of adding or changing the setting of the device need not be carried out and the device can carry out an operation corresponding to the installation position after change.

Second Embodiment

In the first embodiment, the data processing device 990 can determine the position and arrangement order of the own device from the first car (or the last car) but cannot determine the position and arrangement order from the last car (or the first car) and the total number of data processing devices.
Thus, in a second embodiment, the following operation is added to the operation of the first embodiment.
All the relay devices 2 installed in each car 1 are set in such a way that information designating a transmission direction to the main transmission line or the branch transmission line, that is, a packet with a destination IP address "239.0.0.2" (with a destination MAC address "01-00-5E-00-00-02") is relayed to the ports (1) and (3), as shown in FIG. 6. This means that when the packet with the destination IP address "239.0.0.2" is received from the port (1), the packet is relayed only to the port (3), when the packet is received from the port (2), the packet is relayed to the ports (1) and (3), and when the packet is received from the port (3), the packet is relayed only to the port (1). The ports (1), (2) and (3) of the relay device 2 as shown in FIG. 6 are considered synonymous with the ports (1), (2) and (3) of the data relay unit shown in FIG. 2. The destination IP address "239.0.0.2" (with the destination MAC address "01-00-5E-00-00-02") is an example in this embodiment and other values may also be employed.
As shown in FIG. 5, when an event that serves as a trigger that causes the data processing device 990 to start detecting the position and arrangement order occurs, such as turning power on to the car 1, resetting the device, or change in the number of cars or the arrangement order of the cars 1 in the train set due to splitting or coupling of the train set (detection procedure 9001), each data processing device 990 transmits a second position confirmation packet 302 including the information designating the transmission direction to the main transmission line or the branch transmission line, that is, the destination IP address "239.0.0.2" (with the destination MAC address "01-00-5E-00-00-02") as shown in FIG. 6, in addition to the position confirmation packet 301 to the branch transmission line 99 (detection procedure 9011). Here, the internal data of the packet may have an arbitrary value.
The relay device 2, receiving the second position confirmation packet 302 from the branch transmission line 99, that is, from the port (3), relays the packet only to the port (1) of the main transmission line 9 because the destination IP address is "239.0.0.2". The second position confirmation packet 302 reaches the port (2) of a next relay device 2.
Next, when the next relay device 2 receives the second position confirmation packet 302 from the port (2) of the main transmission line 9, the next relay device 2 relays the packet to the port (1) of the main transmission line 9 and the port (3) of the branch transmission line 99 because the destination IP address is"239.0.0.2".
The second position confirmation packet 302 transmitted to the branch transmission line 99 is received by the data processing device 990. The data processing device 990 recognizes the packet as the second position confirmation packet 302 because the destination IP address is"239.0.0.2" and increments the number of the second position confirmation packets 302 received, by one ( detection procedures 9012, 9013, 9014).
The data processing device 990 measures time from a certain time point after the occurrence of the event serving as the trigger. After the lapse of a predetermined time period (detection procedure 9006), the data processing device 990 detects the number of the received second position confirmation packets 302 and determines the position and arrangement order of the own device (the value of Q in detection procedure 9015).
In the example of FIG. 6, after the second position confirmation packet 302 is transmitted from each of the data processing devices 990 of a, b, c and d, the data processing device d receives no second position confirmation packet 302 (Q=0 in FIG. 5), the data processing device c receives one second position confirmation packet 302 (Q=1 in FIG. 5), the data processing device b receives two second position confirmation packets 302 (Q=2 in FIG. 5), and the data processing device a receives three second position confirmation packets 302 (Q=3 in FIG. 5). That is, each data processing device 990 can determine that the own device is the device at the (Q+1)th position from the last car (the arrangement order is the (Q+1)th). Also, the data processing device d of Q=0 can be determined as the last car.
Based on this result (the value of Q) and the result in the first embodiment (the value of P), the data processing device 990 can determine the position and arrangement order thereof and the total number of data processing devices. That is, the total number of the data processing devices 990 is (P+Q+1) and the position of the own device within the train set is the (P+1)th from the first cart and the (Q+1)th from the last car. If each car is equipped with one data processing device each, it is understood that the number of cars in the train set is (P+Q+1) and that the own device is installed in the (P+1)th car.
Based on the values thus found, a setting value, for example, an IP address or the like can be set to device.
Also, whether correct setting is done or not may be checked by making such an arrangement that the information of the position and arrangement order detected by the above procedures, for example, the values of P, Q, P+1, Q+1, P+Q+1 or the like, can be displayed on a display unit such as a light emitting diode (LED) or liquid crystal display unit (LCD) mounted on each data processing device 990 which detects the information, and allowing a maintenance worker of the data processing device 990 to view the display unit from outside.
Up to this point, the second embodiment is described.
According to the second embodiment of the invention, in addition to the advantages of the first embodiment, the total number of devices installed in the train set can be detected and what ordinal number of position the device is installed from the first car and the last car can be determined in all the devices within the train set. Therefore, the position of the own device in the train set can be accurately grasped.
Also, even when there is a change in the number of devices or the like within the train set due to coupling of or splitting into plural train sets, the configuration after autonomous change of each data processing device, that is, the position of the own device within the train set, can be detected.

Third Embodiment

In the first and second embodiments, the main transmission line 9 and the branch transmission line 99 have a single-line configuration. However, in order to improve reliability of the system against transmission line failures, the main and branch transmission lines 9, 99 and the relay device 2 may be configured in multiple lines.
Thus, in a third embodiment, as an example of multiple-line configuration, each relay device 2, the main transmission line and the branch transmission line are configured in dual lines, as shown in FIG. 7. One of the two lines is referred to as line 1. In a line 1 relay device 21, a line 1 main transmission line 91 and a line 1 branch transmission line 991 are connected. The other line is referred to as line 2. In a line 2 relay device 22, a line 2 main transmission line 92 and a line 2 branch transmission line 992 are connected.
The line 1 branch transmission line 991 and the line 2 branch transmission line 992 are connected to the data processing device 990 in each car 1. The data processing device 990 carries out processing similar to the first embodiment or the second embodiment, separately to the line 1 and the line 2. That is, detection of the number of relay devices and the arrangement order is separately carried out in the line 1 and the line 2 and the detection results in the two lines can be compared. If there is a difference between the two detection results as a result of the comparison, it can be understood that there is failure occurring in one of the lines.
For example, a case where a transmission line failure occurs is shown in FIG. 8.
FIG. 8 shows an example in which a failure occurs in the line 1 main transmission line 91 between the second car and the third car.
When each data processing device 990 carries out procedures similar to FIGS., 3 and 4 of the first embodiment, separately in the line 1 and the line 2, the data processing device a has P=0 both in the line 1 and the line 2, and the data processing device b has P=1 in both the line 1 and the line 2. However, the data processing device c has P=0 in the line 1 and P=2 in the line 2. The data processing device d has P=1 in the line 1 and P=3 in the line 2.
In the data processing device c, from P=2 in the line 2, it can be understood that two data processing devices exit on the first car side. However, P=0 in the line 1 indicates that no first position confirmation packet 301 is received from the first car side and therefore it can be understood that there is a failure occurring in the line 1 main transmission line on the first car side or in the line 1 branch transmission line within the own car.
In the data processing device d, from P=3 in the line 2, it can be understood that three data processing devices exit on the first car side. However, P=1 in the line 1 indicates that only one first position confirmation packet 301 is received from the first car side and therefore it can be understood that there is a failure occurring in the line 1 main transmission line beyond the previous car on the first car side.
Meanwhile, when each data processing device 990 carries out procedures similar to FIGS. 5 and 6 of the second embodiment, separately in the line 1 and the line 2, the data processing device a has P=0, Q=1 in the line 1 and P=0, Q=3 in the line 2. The data processing device b has P=1, Q=0 in the line 1 and P=1, Q=2 in the line 2. The data processing device c has P=0, Q=1 in the line 1 and P=2, Q=1 in the line 2. The data processing device d has P=1, Q=0 in the line 1 and P=3, Q=0 in the line 2.
Therefore, when four data processing devices 990 are installed in total and each car is equipped with one data processing device each, each data processing device installed in each car can determine the position of the own device, the number of cars, and the site where a failure occurs. That is, the data processing device a can determine that there are four cars, that the own device is in car No.1, and that there is a failure occurring in the line 1 main transmission line 91 between cars No.2 and No.3. The data processing device b can determine that there are four cars, that the own device is in car No.2, and that there is a failure occurring in the line 1 main transmission line 91 between cars No.2 and No.3. The data processing device c can determine that there are four cars, that the own device is in car No.3, and that there is a failure occurring in the line 1 main transmission line 91 between cars No.2 and No.3. The data processing device d can determine that there are four cars, that the own device is in car No.4, and that there is a failure occurring in the line 1 main transmission line 91 between cars No.2 and No.3.
Also, whether correct detection or setting is done in each data processing device or not may be checked by making such an arrangement that the information of the position and arrangement order in the train set detected by the above procedures, for example, the values of P, Q, P+1, Q+1, P+Q+1 or the like, can be displayed on a display unit such as a light emitting diode (LED) or liquid crystal display unit (LCD) mounted on each data processing device 990 which detects the information for each line, and allowing a maintenance worker of the data processing device 990 to view the display unit from outside. Moreover, a failure occurrence notification function which, for example, turns on a warning lamp or displays a character string showing the occurrence of a failure on the display unit when there is a difference between the two detection results as a result of the comparison of the detection results in the two lines, may be provided.
Up to this point, the third embodiment is described.
According to the third embodiment of the invention, in a multiple-line system such as a dual-line system, the number of devices and the arrangement order are detected separately in each line and the detection results in the lines 1 and 2 are compared. Thus, each data processing device can automatically detect the site of a failure and can show the site where a failure can be occurring. Thus, quick repair work can be carried out.

Fourth Embodiment

In the first to third embodiments, the data processing device 990 connected to the relay device 2 via the branch transmission line 99 detects the position and arrangement order of the own device in the train set. However, in some cases, the relay device 2 itself needs to detect the position (car number) and arrangement order of the own device.
Thus, in a fourth embodiment, a fourth port (port (4)) is provided in the data relay unit 3 and a relay processing control unit 5 is connected to the port (4) via an internal transmission line 995, as shown in FIG. 9. The relay processing control unit 5 has a function of setting a setting value that is necessary for initialization of and relay by the relay device 2 including the data relay unit 3, in the data relay unit 3 and the data distribution unit 4. Such a function can be realized, for example, by using an MII interface installed in KS8995MA, which is switching device made by MICREL INC. (the configuration or the like described in the System Level Applications section of the corresponding data sheet).
The operation in this embodiment can be carried out by procedures similar to FIGS. 3 to 6 of the first and second embodiments, if the port (3) in the first and second embodiments is replaced with the port (4), the branch transmission line 99 is replaced with the internal transmission line 995, the data processing device 990 is replaced with the relay processing control unit 5, and a position confirmation packet including information designating a transmission direction to the main transmission line or the branch transmission line, for example, a destination IP address of a certain value (a different value from the values used in the first and second embodiments), is used.
Also, whether correct detection or setting is done in each relay device 2 or not may be checked by making such an arrangement that the information of the position and arrangement order detected by the above procedures, for example, the values of P, Q, P+1, Q+1, P+Q+1 or the like in the first and second embodiments, can be displayed on a display unit such as a light emitting diode (LED) or liquid crystal display unit (LCD) mounted on each relay device 2 which detects the information, and allowing a maintenance worker of the relay device 2 to view the display unit from outside.
Up to this point, the fourth embodiment is described.
According to the fourth embodiment of the invention, each relay device 2 can autonomously detect the number of cars in the train set and the position (equivalent to the car number) of the own device.
Moreover, even when there is a change in the number of devices or the like within the train set due to coupling of or splitting into plural train sets, the configuration after autonomous change of each relay device 2, that is, the position of the own device within the train set, can be detected autonomously.

Fifth Embodiment

In the information transmission system according to the invention, as the data processing device 990, plural types of data processing device with different operations and functions may coexist, such as a data processing device which controls train traveling functions such as electric motor and brake, and a data processing device which controls other functions than the train traveling functions such as air conditioning and interior lights. Each of these plural types of data processing device needs to detect the position and arrangement order of the own device by type.
Thus, in the first to third embodiments, a position confirmation packet and a second position confirmation packet may be defined by type of data processing device 990, and the position confirmation packet and the second position confirmation packet may be transmitted and received between the data processing devices of the same type, using the technique described in the first to third embodiments.
For example, a data processing device equivalent to an inverter device which controls an electric motor may use "239.0.0.1" as the destination IP address of a position confirmation packet for the inverter device, and a data processing device equivalent to a brake control device which controls the brakes may use "239.0.0.3" as the destination IP address of a position confirmation packet for the brake control device. Moreover, all the relay devices 2 may be set to relay packets with the destination IP address "239.0.0.1" (with a destination MAC address "01-00-5E-00-00-01") and the destination IP address "239.0.0.3" (with a destination MAC address "01-00-5E-00-00-03") to the ports (2) and (3). That is, the relay devices 2 may be set to relay packets with the destination IP addresses "239.0.0.1" and "239.0.0.3" to the ports (2) and (3) when the packets are received from the port (1), relay the packets only to the port (3) when the packets are received from the port (2), and relay the packets only to the port (2) when the packets are received from the port (3), so that each data processing device 990 can selectively receive a position confirmation packet having the destination IP address transmitted from the own device (the destination IP address corresponding to the type of the own device). Thus, the data processing devices of various types can detect the arrangement order of the own device independently by type, using the procedures described in the first embodiment.
Moreover, the data processing device equivalent to an inverter device which controls an electric motor may use "239.0. 0.2" as the destination IP address of a second position confirmation packet for the inverter device, and the data processing device equivalent to a brake control device which controls the brakes may use "239.0.0.4" as the destination IP address of a second position confirmation packet for the brake control device. All the relay devices 2 are set to relay packets with the destination IP address "239.0.0.2" (with a destination MAC address "01-00-5E-00-00-02") and the destination IP address "239.0.0.4" (with a destination MAC address "01-00-5E-00-00-04") to the ports (1) and (3). That is, the relay devices 2 may be set to relay packets with the destination IP addresses "239.0.0.2" and "239.0.0.4" only to the port (3) when the packets are received from the port (1), relay the packets to the ports (1) and (3) when the packets are received from the port (2), and relay the packets only to the port (1) when the packets are received from the port (3), so that each data processing device 990 can selectively receive a second position confirmation packet having the destination IP address transmitted from the own device. Thus, the data processing devices of various types can detect the number of data processing devices of the same type as the own device and the position and arrangement order of the own device independently by type, using the procedures described in the second embodiment.
Also, if the main transmission line 9, the branch transmission line 99 and the relay device 2 are configured in multiple lines, the data processing devices of various types can detect the number of data processing devices of each type and the arrangement order independently for each line and independently by type, using the procedures described in the third embodiment. Moreover, by comparing the results of detection between the lines, the site of failure can be detected.
Up to this point, the fifth embodiment is described.
According to the fifth embodiment of the invention, plural data processing devices can detect the position and arrangement order of the data processing devices of each type, independently by type, in addition to the advantages of the first to third embodiments.

Sixth Embodiment

In the first to fifth embodiments, the respective cars are connected and a wired transmission line is assumed as the main transmission line 9 connecting the relay devices 2 next to each other. However, a mixed configuration using a wireless transmission line and a wired transmission line can be used for the main transmission line 9, as shown in FIG. 10.
That is, in the example shown in FIG. 10, a car A 11, a car group B 12 and a car C 13 form one train set. The car A 11 and the car C 13 are made up of a single car each. The car group B 12 is made up of plural cars connected to each other. The main transmission line 9 between the car A 11 and the car group B 12 is formed by a wireless transmission line. The main transmission line 9 between the plural cars 1 belonging to the car group B is formed by a wired transmission line. The main transmission line 9 between the car group B 12 and the car C 13 is formed by a wireless transmission line.
At forefront parts and rear parts of the car A, the car group B and the car C, a wireless device 93 and an antenna device 930 are connected to the relay device 2, as shown in FIG. 10. Data outputted from the relay device 2 is converted into a wireless signal by the wireless device 93 and transmitted to the wireless transmission line from the antenna device 930. In the next car, the wireless signal received by the antenna device 930 from the wireless transmission line is converted by the wireless device 93 into data to be inputted to the relay device 2, and the data is inputted to the relay device 2. The antenna device 930 has a property of transmitting and receiving wireless radio waves only in a predetermined direction and may include a single antenna or an array of plural antennas.
The operations of other devices and data processing procedures are similar to the first to fifth embodiments.
The wireless system used for the wireless transmission line is not particularly limited. Wireless LANs conforming to the IEEE 802.11, IEEE 802.15, IEEE 802.16 standards and the like may be used, or wireless systems used for mobile phones or the like may be used. Also, wireless systems assumed to be used in railways and automobiles or the like such as train radio and DSRC may be used.
In the case of the wireless transmission line, unlike the wired transmission line, when there are plural cars in the same directions, the antenna device 930 directly receives wireless signals not only from the next car but also from a distant car beyond the next car, and the data processing device may make an error in detecting the arrangement order or the like. For example, in the example of FIG. 10, the car group B 12 and the car A 11 exist in a forward direction as viewed from the car C 13. Therefore, as a signal transmitted from the car A 11, two signals, that is, a signal relayed by the car group B 12 and a signal arriving directly from the car A 11, may be received in the car C 13. In this case, the data processing device 990 in the car C 13 duplicately counts the data from the car A 11 and therefore the main transmission line 9 installed in the car A 11 makes an error in detecting the arrangement order. Thus, each data processing device transmits a different signal from each other as a position confirmation packet. When the data processing device of the transmission source receives a plural number of the same position confirmation packets, a detection error can be avoided by a technique in which the wireless device 93 in each car outputs only the packet that is received first to the relay device 2 and disposes of the packet that is received later, or outputs only the packet with the highest receiving radio intensity (the packet that is transmitted from the nearest car) to the relay device 2 and disposes of the other packets, or the like.
Up to this point, the sixth embodiment is described.
According to the sixth embodiment of the invention, by replacing the main transmission line 9 with a wireless transmission line, there is no need to connect or disconnect of the transmission line every time coupling of or splitting into plural cars is carried out, which is necessary in the case of the wired transmission line. Also, cars or car groups connected via the wireless transmission line need not physically be connected and similar effects can be achieved even when these cars or car groups travel in a physically distant state. Therefore, even when the arrangement order is changed during the traveling, the arrangement order can be detected again each time and the new configuration can be grasped.
Thus, according to this embodiment, the invention can be applied not only to railway cars but also to moving bodies such as automobiles and buses traveling in a row in the same direction without having plural cars connected to each other, and ships and airplanes.

Seventh Embodiment

In the first to sixth embodiments, a display device 8 can be connected at one or plural positions in the main transmission line 9, as shown in FIG. 12, and the display device 8 can detect and display the position and number of data processing devices 990.
That is, the display device 8 receives the position confirmation packet and the second position confirmation packet as shown in FIGS. 4 and 6, and detects the values "P" and "Q" described in the first or second embodiment. Thus, the position and number of data processing devices is displayed on the display device 8.
Also, the position and number of data processing devices can be displayed on the display device 8 by type of data processing device, using the technique described in the fifth embodiment.
An example of configuration of the display device 8 includes: an arithmetic device 2800 equipped with a CPU which detects the number of position confirmation packets and second position confirmation packets, a cache memory, a main storage memory and the like; a storage device 2803 such as a hard disk, silicon disk or non-volatile memory which stores transmission and reception data, a processing program, initial setting information, log information and the like; a transmission line interface device 2801 having a function of receiving the position confirmation packet and the second position confirmation packet from the main transmission line 9 and the branch transmission line 99; and an output device 2805 such as a light emitting diode (LED) or liquid crystal display unit (LCD) which displays the detection result, as shown in FIG. 13. The display device 8 may also be provided with an input device 2804 such as a switch or keyboard to input initial setting items like an address and the operation mode of the transmission line, if necessary.
The display device 8 may also be connected to the branch transmission line 99 similarly to the other data processing devices 990, as shown in FIG. 14. However, when the display device 8 is connected to the branch transmission line 99, the data distribution unit 4 in the relay device 2 needs to relay the position confirmation packet and the second position confirmation packet transmitted from the connected data processing device 990, to both the data relay unit 3 and the display device 8.
Up to this point, the seventh embodiment is described.
According to the seventh embodiment of the invention, the position and number of data processing devices 990 can be confirmed using the display device 8. If the display device 8 is installed on the cab or in the passenger rooms of cars, confirmation of connection by the data processing devices can be easily carried out even when there is a change in the train set due to coupling or splitting of cars.

Claims

An information transmission device for a railway car for transmitting data between railway cars of a train set made up of plural railway cars, the device comprising:
a relay device which is connected with a relay device of a next car via a main transmission line and carries out relay processing of data received from the next car; and

a data processing device connected with the relay device via a branch transmission line;

wherein when the data processing device outputs data including information of a transmission direction to the relay device, the relay device has a unit which decides a relay direction of the data in accordance with the information of the transmission direction included in the data received from the branch transmission line or the main transmission line; and

the data processing device detects a position of own device in the train set from the data received from the relay device.
The information transmission device according to claim 1, wherein the data processing device detects what ordinal number of position from an end of the train set the own device is connected to, based on the number of the data that is received.
The information transmission device according to claim 1 or 2, wherein the information of the transmission direction included in the data is an address indicating a destination of the data.
The information transmission device according to one of claims 1 to 3, wherein the data processing device
outputs plural kinds of data with different information of transmission direction to the relay device, and
detects what ordinal number of position from an end of the train set the own device is connected to based on the number of the data of each kind received from the relay device, and detects a total number of the data processing devices connected within the train set.
The information transmission device according to one of claims 1 to 4, wherein the main transmission line and the relay device are configured in multiple lines, and
the data processing device
outputs the data including the information of the transmission direction to the relay device in each line, and
receives the data from the relay device in each line, detects the number of the data that is received from each line, and determines that there is an abnormality occurring in the main transmission line or the branch transmission line when the detected number of the data is different between the lines.
The information transmission device according to one of claims 1 to 5, wherein as the data processing device, plural types of data processing device with different functions exist, and wherein the data processing device transmits data to the relay device, the data includes information designating a transmission direction, and the information designating the transmission direction is different between the types.
The information transmission device according to one of claims 1 to 6, wherein the data processing device or the relay device detects at least a position and arrangement order of the own device and has a display unit which displays a result of detection.
The information transmission device according to one of claims 1 to 6, wherein the transmission line is formed by one or both of a wireless transmission line and a wired transmission line.
The information transmission device according to one of claims 1 to 6, wherein a display device is connected to the transmission line and is made to display the position and number of the data processing device.
A train set comprising the information transmission device according to one of claims 1 to 9, wherein each railway car forming the train set has at least the relay device and the data processing device.
An information transmission method in which
a relay device which is connected with a relay device installed in a next car via a main transmission line and carries out relay processing of data received from the next car, and
a data processing device connected with the relay device via a branch transmission line, are provided, and
data is transmitted between railway cars of a train set made up of plural railway cars,
the method comprising:
a step in which data including information of a transmission direction is outputted from the data processing device to the relay device;

a step in which the relay device, receiving the data, decides a relay direction of the data in accordance with the information of the transmission direction included in the data; and

a step in which the data processing device, receiving the data, detects a position of own device in the train set in accordance with the number of times the data is received.
The information transmission method according to claim 11, wherein in the step in which the data processing device, receiving the data, detects the position of the own device in the train set in accordance with the number of times the data is received, the number of times the data is received plus 1 is determined as a connection position of the own device from an end of the train set.
The information transmission method according to claim 11 or 12, further comprising:
a step in which plural kinds of data including different information of transmission direction is outputted from the data processing device to the relay device;

a step in which the relay device, receiving the plural kinds of data, decides a relay direction of each of the data in accordance with the information of transmission direction included in the plural kinds of data; and

a step in which the data processing device, receiving the plural kinds of data, detects what ordinal number of position from an end of the train set the own device is connected to in accordance with the number of times each of the plural kinds of data is received, and detects a total number of the data processing devices connected within the train set.
The information transmission method according to one of claims 11 to 13, wherein the main transmission line and the relay device are configured in multiple lines, and
the method further comprises:
a step in which the data including the information of transmission direction is outputted from the data processing device to the relay device in each line;

a step in which the relay device in each line, receiving the data, decides a relay direction of the data in accordance with the information of transmission direction included in the data; and

a step in which the data processing device, receiving the data, detects the number of times the data is received from each line, and determines that there is an abnormality occurring in the main transmission line or the branch transmission line when the detected number of the data is different between the lines.
The information transmission method according to one of claims 11 to 14, wherein information of the detected position of the own device in the train set is displayed on a display device.