JPS58172049A - Signal transmission system - Google Patents

Abstract

PURPOSE:To improve the reliability of the whole of a signal transmission system wherein respective stations are looped, by transmitting a message from the (n-1)th station to the (n)th and the (n+1)th stations. CONSTITUTION:In addition to a normal flow M1-M2-M3-M4-M5 of a message, a transmission line provides another flow M1'-M3'-M5'-M2'-M4'. If part of the transmission system, e.g. the 3rd station 3 becomes unable to operate, the 4th station 4 once detecting a failure in receiving a message M3 from a reception part R1 performs such switching that a message M2' is received from the reception part R2.Consequently, an answer message of its station is combined with the message M2' to form a message M4, which is transmitted to the 5th station 5. Therefore, if a fault occurs in a part of the transmission system or a station, messages are transmitted without shutting down the whole system.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a signal transmission system in which a main station, which is a first station each equipped with a transmitter/receiver, and a plurality of secondary stations and subsequent stations are sequentially connected in a loop. The purpose of this is to increase the reliability of the system against the occurrence of failures by providing redundancy to the transmission path of the signals being transmitted.

Conventionally, there has been a signal transmission system of this type as shown in FIG. In the figure, (1) is the first station which is the main station, (
2) to (5) are slave stations, and these 1st to 5th stations are each equipped with a transmitter/receiver, and are sequentially connected in a loop shape so that messages from the master station (1) are transmitted to each slave station (2). ~
(6), and the responses from each of the slave stations (2) to (5) are transmitted to the master station (1). In the figure, R and T are the receiving end and transmitting end of the transceiver provided at each station.

That is, in the illustrated configuration, the message M from the first station, which is the main station, is first given to the second station (2), and the second station (2) receives the mosquito message M□ and is requested to respond. If so, the response message of the own station is concatenated with this and sent as message 1 to the fifth station (8). 6th station (
8) receives the message from the first station via message M, and if a response is required, concatenates its own response message thereto and transmits it to the fourth station (4) as message M5. Thereafter, the message is transmitted to the next station in the same manner, and the final message is transmitted from the final station to the first station (1).

In this way, the master station (1) transmits its own message to each slave station, and also receives response messages from each slave station connected to the message.

However, since conventional signal transmission systems are configured as described above, even if one of the signal transmission lines that connect each station in a loop is disconnected, or one of the slave stations is disconnected due to a power outage, etc. Even in the event of a failure, messages from the master station will not be transmitted to the slave stations in the stages following the point of failure, and the master station will not be able to receive response messages from each slave station, causing the entire system to go down. Therefore, the present invention adds another transmission path to the conventional signal transmission path, and solves the conventional problem that the entire system goes down due to a failure in a part of the transmission system. The purpose of the present invention is to provide a signal transmission system that can solve the problems of conventional devices.

Hereinafter, one embodiment of the present invention will be described with reference to FIG. 2, in which the same parts as in FIG. 1 are denoted by the same reference numerals.

In FIG. 2, there are two receiving sections R in each of the first to fifth stations.

It has R3 and two transmitters T and T2, and is configured to transmit messages from its own station to the next station and the next station in a loop configuration.

In other words, the first station (1) sends the message M to the second station (2).
) and simultaneously transmits the message M□' to the fifth station, and the second station (2) transmits the message M2 to the sixth station (8) and at the same time transmits the message M, / to the fourth station.

Further, the fourth station (4) transmits the message M4 to the fifth station, which is the final stage, and at the same time transmits the message y, / to the first station (1), which is the master station, and at the same time, the fourth station (4) transmits the message M4 to the fifth station, which is the final stage, and transmits the message y, / to the first station (1), which is the master station. 6) transmits MI5 as the final message to the first station (1) and at the same time transmits the message M, / to the second station (2). Each station receives messages from the previous station in its respective receiving sections of R and R8, but messages received from the R side are given priority. Furthermore, the contents of the messages transmitted by each station at the transmitting sections of T and T are the same.

Therefore, the operation under normal conditions when there is no failure in the transmission system is as follows.0 First, the message M from the first station (1) is sent to the second station (2).
), and the second station (2) receives information from this message to its own station, and also concatenates its own response message to this message to form message M, which is then transmitted to the third station (8). do. The fifth station (8) receives and receives the information sent to its own station, and also concatenates the response message of its own station to form a message M3, which is transmitted to the fourth station (4). The fourth station (4) concatenates its own response message to this message and transmits it to the fifth station (6) as message M6, and the fifth station (6) also transmits the message of 5- to the message M6. The response messages are concatenated to form a message Ma, and the first station (1) receives this final message, thereby transmitting the message from the first station (1), which is the master station, to the second to fifth stations, which are slave stations. and collection of response messages from each station. The above operation is the same as the conventional case shown in Figure 1, and this is
This is realized by giving priority to the R1 side among the two receiving sections R□ and R8.

Next, considering the case where a failure occurs in one part of the transmission system, 1
If the station becomes inoperable due to a power outage, - For example, if the third station (8) becomes inoperable, in this case, the fourth station (4) will receive the message M, by the receiver R0 side. It becomes impossible to receive messages, but when it detects that the non-receiving state continues for a long time, the receiving section R2 side performs a switch to accept the received message M2/, and as a result, the local station responds to the messages M, /. The messages are concatenated and sent as message M4 to the fourth station (4). Message M, / has the same content as message M, and the first
Since it is a concatenation of the message y□ of station (1) 6- and the response message of station M2 (2), compared to the message M received by the fourth station (4) in a normal case, the message y□ of the fifth station ( 8) only the response message is missing. The flow of messages is Myu→M, 4M, -0M, bypassing the 5th station (81).In this way, if one station becomes inoperable, the other stations will be affected. This also applies to other failures that are equivalent to making one station inoperable, such as a break in the signal line of one station.Also, the second station (2) and the fourth station (4), 5th station (
6) etc. becomes inoperable, a similar bypass function operates. Bypassing a failed station is also possible when multiple stations become inoperable, except when two adjacent stations become inoperable.

In addition, if the signal line is disconnected at a specific point, consider, for example, the case where the signal line transmitting the message M3 is disconnected. In this case, the bypass mechanism described above will change the flow of the message from M → y to I. →M6→M, and the 5th station (
The effect is limited to the fact that the first station (1), which is the main station, is unable to receive the response message of 8). However, the main station (1), which detected that there was no response message from the fifth station (8), gave a command to all stations, and
If the priority relationship in 3 is switched, that is, if the R2 side is made the priority side in each station, the message flow will be M'→
y, /→y, /→M, /→M, /, the main station (1) can receive response messages from all stations, and it is also possible to recover from the failure.

In other words, the flow of messages during normal times is V→M, -)M
3→M4→M, another message flow Jl
This is possible because it has the following transmission paths: →M, I→y, /→y, /→M, /.

In addition, in the above example, the first station (1) is the main station, but
As can be understood from Fig. 2, the signal lines for each station are symmetrical. The present invention can be similarly applied to a system in which a station having a main station function is switched to another station in accordance with conditions such as switching between the two leading driver's cabs or occurrence of a failure in the main station.

Furthermore, although in the above example two transmitters were provided for each round, the present invention can also be applied to a system in which there is only one transmitter and the signal is distributed into two. Furthermore, the present invention can of course be applied to a system in which there is only one receiving section instead of two receiving sections, and the connection to the signal line is changed over using a switch. Of course, this is not limited to certain cases.

As mentioned above, adding one more set of transmitting section and one receiving section to each station (or providing an equivalent function), and 2.
By simply providing a simple switching logic in each station to determine which of the two receivers to give priority to reception, it is possible to discover the location of a fault and eliminate the need for complex processing to take countermeasures when a fault occurs on the entire system. To achieve the effect of minimizing the impact, and to eliminate the disadvantage that the entire system becomes inoperable due to a failure occurring in one part, such as a failure of one station or a disconnection of a transmission line at one location. I can do it. If you simply want to avoid the effects of a failure in the transmission system, you can simply duplicate the transmission system, but in that case, it is not effective against station failures, so the effect is limited. The present invention is effective in both cases of failure between transmission systems.

As described above, according to the present invention, in a G transmission system in which each station is connected in a loop, a message from the (n-1)th station is transmitted to the nth station and the (n+1)th station. Therefore, even if a failure occurs in one part of the transmission system or the station, messages can be transmitted without bringing down the entire system, and the reliability of the entire system can be improved.

[Brief explanation of drawings]

FIG. 1 is a connection diagram showing a conventional signal transmission system, and Section 2 is a connection diagram showing a signal transmission system according to an embodiment of the present invention. (1) to (6)... 1st to 5th EIJ y to M M/ to M'... Message l III l In the figures, the same reference numerals indicate the same or corresponding parts. -10°

Claims (2)

[Claims] (1) Consisting of a first station, which is a master station, each equipped with a transmitter/receiver, and a plurality of slave stations below the second station, these multiple stations are sequentially connected in a loop, and each slave station is In a signal transmission system that receives messages from a station, connects responses to messages from the main corridor and transmits them to subsequent slave stations, and transmits the responses of each slave station to the main station, the total number of stations is 1 if n stations are
A signal transmission system characterized in that a message from the (n-1)th station is transmitted to the nth station and the (n+1)th station. (2) The scope of the claim is that the first to nth stations are mounted on a railway vehicle and distributed within the train, and the main station is not fixed to a specific station but can be switched according to conditions. The signal transmission system according to item 1.