FORM 2
THE PATENTS ACT, 1970
(39 of& 1970) THE PATENTS RULES, 2003 COMPLETE SPECIFICATION
[See section 10, Rule 13]
SIGNAL CONTROL DEVICE AND ABNORMALITY DETECTION METHOD;
MITSUBISHI ELECTRIC CORPORATION, A CORPORATION ORGANISED
AND EXISTING UNDER THE LAWS OF JAPAN, WHOSE ADDRESS IS 7-3,
MARUNOUCHI 2-CHOME, CHIYODA-KU, TOKYO 1008310, JAPAN
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE
INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED.
2
DESCRIPTION
Field
[0001] The present invention relates to a signal control
device that is mounted to a train and also relates to an
5 abnormality detection method.
Background
[0002] If a signal control device which performs control
by outputting a signal to a vehicle system fails and some
10 unintentional signal is outputted from the failure signal
control device to the vehicle system during operation of a
train, there is a possibility that the vehicle system
malfunctions. Therefore, detection of abnormality of the
signal control device is desirable in order to prevent the
15 vehicle system from malfunctioning. According to a
technique disclosed in Patent Literature 1, a railroad
safety control device includes a plurality of control
systems that control devices of a vehicle system by
outputting a signal to the vehicle system. Each of the
20 control system performs mutual collation of data sets that
are inputted and outputted between the control system and
the devices of the vehicle system to determine whether
there is a failure in the control system or not. When the
failure in the control system is detected, operation of a
25 train is brought to a stop.
Citation List
Patent Literature
[0003] Patent Literature 1: Japanese Patent Application
30 Laid-open No. 2000-255431
3
Summary
Technical Problem
[0004] However, according to the above conventional
technique, the train that is in the process of operation
5 needs to be stopped. Therefore, a lot of time and effort
are problematically required to restore operation control
of the train to a normal state. In addition, because of
the configuration including two or more control systems,
the device gets problematically larger.
10 [0005] The present invention has been made in view of
the above circumstances, and an object of the present
invention is to obtain a signal control device that can
detect abnormality before operation of a train is performed,
with a simple configuration.
15
Solution to Problem
[0006] In order to solve the above-stated problems and
achieve the object, the present invention provides a signal
control device mounted to a train, the signal control
20 device comprising: an output unit to output a signal to an
external device mounted to the train; and a controller to
control whether or not to cause the output unit to output
the signal, wherein the output unit includes a readback
circuit to detect whether or not the signal is outputted
25 from the output unit, and the controller makes a signal
stop request and a signal output request to the output unit
before operation of the train starts, acquires a detection
result of the readback circuit while each of the signal
stop request and the signal output request is performed,
30 and detects abnormality of the output unit using the
detection result.
4
Advantageous Effects of Invention
[0007] A signal control device according to the present
invention can detect abnormality before operation of a
train is performed, with a simple configuration.
5
Brief Description of Drawings
[0008]
FIG. 1 is a block diagram illustrating a configuration
example of a RIO (Remote Input Output) device according to
10 a first embodiment.
FIG. 2 is a flowchart illustrating an abnormality
detection process of the RIO device according to the first
embodiment.
FIG. 3 illustrates signal output states of constituent
15 elements of the RIO device according to the first
embodiment.
FIG. 4 illustrates an example in which a processing
circuit of the RIO device according to the first embodiment
is configured to include a processor and a memory.
20 FIG. 5 illustrates an example in which the processing
circuit of the RIO device according to the first embodiment
is configured as a dedicated hardware set.
FIG. 6 is a block diagram illustrating a configuration
example of a RIO device according to a second embodiment.
25 FIG. 7 is a flowchart illustrating an abnormality
detection process of the RIO device according to the second
embodiment.
FIG. 8 illustrates signal output states of constituent
elements of the RIO device according to the second
30 embodiment.
FIG. 9 is a block diagram illustrating a configuration
example of a RIO device according to a third embodiment.
FIG. 10 is a flowchart illustrating an abnormality
5
detection process of the RIO device according to the third
embodiment.
FIG. 11 illustrates signal output states of
constituent elements of the RIO device according to the
5 third embodiment.
FIG. 12 is a block diagram illustrating a
configuration example of a RIO device according to a fourth
embodiment.
FIG. 13 is a flowchart illustrating an abnormality
10 detection process of the RIO device according to the fourth
embodiment.
FIG. 14 illustrates signal output states of
constituent elements of the RIO device according to the
fourth embodiment.
15
Description of Embodiments
[0009] With reference to the drawings, a detailed
description is hereinafter provided of signal control
devices and abnormality detection methods according to
20 embodiments of the present invention. It is to be noted
that these embodiments do not necessarily limit the present
invention.
[0010] First Embodiment.
In the present embodiment, one example of a signal
25 control device is a RIO device. A description is
hereinafter provided of an example in which the RIO device
is mounted to a train that is not illustrated. FIG. 1 is a
block diagram illustrating a configuration example of the
RIO device 1 according to the first embodiment of the
30 present invention. The RIO device 1 is connected to a
relay 2 and a display device 3. The RIO device 1 outputs,
to the relay 2, a digital output (DO) signal, that is, a
110 V direct current signal in this example. The 110 V
6
direct current signal that is outputted as the DO signal
from the RIO device 1 is given as one example, and a DO
signal is not limited to a 110 V direct current signal.
The relay 2 is an external device whose operation is
5 controlled by the RIO device 1 and is here an onboard
device mounted to the train. The relay 2 is one example of
an onboard device, and an onboard device connected to the
RIO device 1 is not limited to the relay 2. When the RIO
device 1 has detected its abnormality, the display device 3
10 displays, under control of the RIO device 1, that the RIO
device 1 has the abnormality. The display device 3 is, for
example, a monitor installed in a train cab that is not
illustrated.
[0011] A description is provided of the configuration of
15 the RIO device 1. The RIO device 1 includes a controller
10, an output unit 20, a control power supply 30, and a
breaker 40. The controller 10 controls whether or not to
cause the output unit 20 to output the DO signal. Under
control of the controller 10, the output unit 20 outputs
20 the DO signal to the relay 2 mounted to the train. The
control power supply 30 supplies power to the output unit
20. Under control of the controller 10, the breaker 40
controls the supply of power from the control power supply
30 to the output unit 20.
25 [0012] A description is provided of a configuration of
the output unit 20. The output unit 20 includes a
photocoupler 21, a diode 22, and a readback circuit 23.
The photocoupler 21 outputs the DO signal when the
controller 10 has made a signal output request and does not
30 output the DO signal when the controller 10 has made a
signal stop request. The diode 22 prevents backflow of a
signal from a side of the relay 2. The readback circuit 23
includes a photocoupler 24. The photocoupler 24 is
7
connected to a connecting point between the photocoupler 21
and the diode 22 and detects that the DO signal has been
outputted from the photocoupler 21. In other words, the
photocoupler 24 detects an output state of the DO signal
5 from the photocoupler 21. This output state is either a
state of the DO signal being outputted from the
photocoupler 21 or a state of no DO signal being outputted
from the photocoupler 21. The readback circuit 23 outputs,
to the controller 10, a detection result indicative of the
10 output state of the DO signal. Using the detection result
obtained from the readback circuit 23, the controller 10
detects the abnormality of the output unit 20. The
abnormality of the output unit 20 corresponds, for example,
to failure of the output unit 20.
15 [0013] A description is provided next of an abnormality
detection process of the RIO device 1. FIG. 2 is a
flowchart illustrating the abnormality detection process of
the RIO device 1 according to the first embodiment. FIG. 3
illustrates signal output states of the constituent
20 elements of the RIO device 1 according to the first
embodiment. Illustrated in a top row of FIG. 3 is a signal
outputted from the controller 10. A middle row of FIG. 3
illustrates whether or not the DO signal is outputted from
the output unit 20. Illustrated in a bottom row of FIG. 3
25 is a detection result of the readback circuit 23, that is,
a signal outputted from the readback circuit 23.
Characters indicated in FIG. 3 including S101 and so on are
characters indicative of steps in the flowchart of FIG. 2.
As illustrated in the top row of FIG. 3, the signal
30 outputted from the controller 10 takes on either one of
values that represent two levels including a low (L) level
and a high (H) level. The low (L) level indicates the
signal stop request to the output unit 20, while the high
8
(H) level indicates the signal output request to the output
unit 20. The signal stop request is an instruction issued
by the controller 10 to request the output unit 20 not to
output the DO signal. The signal output request is an
5 instruction issued by the controller 10 to request the
output unit 20 to output the DO signal. As illustrated in
the middle row of FIG. 3, depending on whether or not the
DO signal is outputted from the output unit 20, either one
of values representing two levels including a low (L) level
10 and a high (H) level is taken. The low (L) level indicates
the state of no DO signal being outputted, while the high
(H) level indicates the state of the DO signal being
outputted. As illustrated in the bottom row of FIG. 3, the
detection result of the readback circuit 23 takes on either
15 one of values that represent two levels including a low (L)
level and a high (H) level. The low (L) level indicates no
DO signal being outputted from the output unit 20, while
the high (H) level indicates the DO signal being outputted
from the output unit 20. It is to be noted that the above
20 settings for the low (L) level and the high (H) level
indicating an output state of each signal is one example
and some settings reverse of the example shown in FIG. 3
may be realized. The same applies to those embodiments
that follow.
25 [0014] When the RIO device 1 is activated, the
controller 10 makes the signal stop request to the output
unit 20 before operation of the train mounted with the RIO
device 1 starts (step S101). While the signal stop request
is made from the controller 10, the output unit 20 does not
30 output the DO signal from the photocoupler 21 (step S102).
Moreover, the readback circuit 23 of the output unit 20
outputs to the controller 10 the detection result
indicative of no DO signal being outputted from the output
9
unit 20 (step S103).
[0015] The controller 10 obtains from the readback
circuit 23 the detection result obtained during the signal
stop request being made as the instruction and cross-checks
5 the obtained detection result against the request made to
the output unit 20 (step S104). In the example of FIG. 3,
since the detection result (step S103) indicating no DO
signal being outputted from the output unit 20 is obtained
in response to the signal stop request (step S101), the
10 controller 10 determines that the output unit 20 is normal.
[0016] Next, the controller 10 makes the signal output
request to the output unit 20 (step S105). During the
signal output request being made as the instruction by the
controller 10, the output unit 20 outputs the DO signal
15 from the photocoupler 21 (step S106). Moreover, the
readback circuit 23 of the output unit 20 outputs to the
controller 10 the detection result indicative of the DO
signal being outputted from the output unit 20 (step S107).
[0017] The controller 10 obtains from the readback
20 circuit 23 the detection result obtained during the signal
output request being made as the instruction and crosschecks
the obtained detection result against the request
made to the output unit 20 (step S108). In the example of
FIG. 3, since the detection result (step S107) indicating
25 the DO signal being outputted from the output unit 20 is
obtained in response to the signal output request (step
S105), the controller 10 determines that the output unit 20
is normal. It is to be noted that the orders of the
processes of step S101 to step S104 and the processes of
30 step S105 to step S108 may be exchanged. If there is
enough time before the operation of the train mounted with
the RIO device 1 starts, the RIO device 1 may execute the
processes of step S101 to step S108 multiple times in order
1 0
to improve abnormality detection accuracy.
[0018] If the controller 10 determines at both step S104
and step S108 that the output unit 20 is normal (step S109:
Yes), the controller 10 continues monitoring an operating
5 state of the output unit 20 through continual acquisition
of the detection result from the readback circuit 23 after
the start of the operation of the train (step S110). The
continued monitoring of the operating state of the output
unit 20 means that the controller 10 checks whether or not
10 the DO signal is actually outputted on the basis of the
detection result obtained from the readback circuit 23 in
response to the signal output request or the signal stop
request for the DO signal, which are made to the output
unit 20 in association with the actual operation of the
15 train.
[0019] If the controller 10 determines at either or both
of steps S104 and S108 that the output unit 20 is abnormal
(step S109: No), the controller 10 controls the breaker 40
to stop the supply of power from the control power supply
20 30 to the output unit 20, thus stopping operation of the
output unit 20 (step S111). Specific abnormal cases of the
output unit 20 include a case where the detection result of
the readback circuit 23 is high (H) when the signal from
the controller 10 is low (L) at step S104 and a case where
25 the detection result of the readback circuit 23 is low (L)
when the signal from the controller 10 is high (H) at step
S108. If, for example, there is unintended output of the
DO signal from the output unit 20 due to the abnormality of
the output unit 20, it is expected to be incapable of
30 stopping output of the DO signal even through the
controller 10 tries to control the output unit 20.
Therefore, the controller 10 stops the supply of power from
the control power supply 30 to the output unit 20, thereby
1 1
forcing the operation of the output unit 20 to be stopped.
In this way, the controller 10 can prevent the train
mounted with the RIO device 1 from malfunctioning when the
unintended DO signal is outputted from the output unit 20.
5 [0020] The controller 10 causes the display device 3 to
display that the output unit 20 or the RIO device 1 has the
abnormality (step S112). By so doing, a user who is, for
example, a motorman can be aware of the abnormality of the
RIO device 1 when checking contents provided by the display
10 device 3.
[0021] As described above, when the output unit 20 has
the abnormality, the RIO device 1 can detect the
abnormality of the output unit 20 at an early stage by
checking the operating state of the output unit 20 before
15 the start of the operation of the train.
[0022] A description is provided next of a hardware
configuration of the RIO device 1. The output unit 20 of
the RIO device 1 is a digital signal output circuit. The
control power supply 30 is a direct current power supply
20 that supplies, for example, a 5 V direct current power to
the output unit 20. The breaker 40 is a switch configured
to control the supply of power from the control power
supply 30 to the output unit 20 under the control of the
controller 10. The controller 10 is implemented by a
25 processing circuit. In other words, the RIO device 1 is
equipped with a processing circuit that is capable of
detecting the abnormality of the output unit 20 at the
early stage. The processing circuit may be a memory and a
processor that executes a program stored in the memory or
30 may be of dedicated hardware.
[0023] FIG. 4 illustrates an example in which the
processing circuit owned by the RIO device 1 according to
the first embodiment is configured by using a processor and
1 2
a memory. When the processing circuit is configured using
the processor 91 and the memory 92, functions of the
processing circuit of the RIO device 1 is implemented by
software, firmware, or a combination of software and
5 firmware. The software or the firmware is described as a
program and stored in the memory 92. In the processing
circuit, the processor 91 reads and executes the programs
stored in the memory 92 thereby implementing the functions.
This means that the processing circuit has the memory 92
10 for storing the programs by which early detection of the
abnormality of the output unit 20 is realized. In addition,
these programs can be said to cause a computer to execute
the steps and the method of the RIO device 1.
[0024] The processor 91 may here be, for example, a
15 central processing unit (CPU), a processing device, an
arithmetic device, a microprocessor, a microcomputer, or a
digital signal processor (DSP). The memory 92 corresponds
to: for example, a nonvolatile or volatile semiconductor
memory such as a random-access memory (RAM), a read-only
20 memory (ROM), a flash memory, an erasable programmable ROM
(EPROM), or an electrically EPROM (EEPROM) (registered
trademark); a magnetic disk; a flexible disk; an optical
disk; a compact disk; a mini disk; or a digital versatile
disc (DVD).
25 [0025] FIG. 5 illustrates an example in which the
processing circuit owned by the RIO device 1 according to
the first embodiment is configured by dedicated hardware.
When the processing circuit is configured by the dedicated
hardware, a processing circuit 93 illustrated in FIG. 5
30 corresponds to, for example, a single circuit, a composite
circuit, a programmed processor, a parallel programmed
processor, an application specific integrated circuit
(ASIC), a field-programmable gate array (FPGA), or any
1 3
combination of them. Each of the functions of the RIO
device 1 may be implemented by the processing circuit 93 or
all the functions may be implemented by the processing
circuit 93.
5 [0026] It is to be noted that some of the functions of
the RIO device 1 may be implemented by dedicated hardware,
while the rest of the functions may be implemented by
software or firmware. As mentioned above, the processing
circuit can realize the above-described functions using
10 dedicated hardware, software, firmware or any combination
of them.
[0027] According to the present embodiment described
above, after the RIO device 1 is activated, the RIO device
1 makes the signal stop request and the signal output
15 request to the output unit 20 before the start of the
operation of the train. Then, the RIO device 1 acquires a
detection result indicative of the output state of the DO
signal from the output unit 20 from the readback circuit 23
of the output unit 20. Further, the RIO device 1
20 determines the operating state of the output unit 20 on the
basis of the request made to the output unit 20 and the
detection result. Before the operation of the train starts,
the RIO device 1 voluntarily makes the signal stop request
and the signal output request that are not related to the
25 operation of the train, requests being made to detect the
abnormality of the output unit 20. By doing so, when the
output unit 20 has the abnormality, the RIO device 1 can
detect the abnormality of the output unit 20 before the
operation of the train. Moreover, the RIO device 1 can
30 detect the abnormality of the output unit 20 with a simple
configuration without two or more control systems.
[0028] Second Embodiment.
A RIO device according to the second embodiment is
1 4
configured to include an input unit. A description is
provided of a part different from the first embodiment.
[0029] FIG. 6 is a block diagram illustrating a
configuration example of a RIO device 1a according to the
5 second embodiment. The RIO device 1a is connected to a
relay 2a and the display device 3. Upon receiving input of
a DO signal from the RIO device 1a, the relay 2a outputs a
signal indicative of an operating state based on the
inputted DO signal. The signal outputted from the relay 2a
10 is inputted as a digital input (DI) signal to the RIO
device 1a.
[0030] A description is provided of the configuration of
the RIO device 1a. As compared with the RIO device 1 of
the first embodiment illustrated in FIG. 1, the RIO device
15 1a includes a controller 10a in place of the controller 10
and additionally includes an input unit 50 that includes a
feedback circuit 51. The feedback circuit 51 of the input
unit 50 includes a photocoupler 52. The photocoupler 52
detects a signal outputted from the relay 2a as a DI signal.
20 The feedback circuit 51 outputs, to the controller 10a, a
detection result that indicates an input state of the DI
signal, that is, whether or not the DI signal is inputted.
In the second embodiment, the control power supply 30
supplies power to the input unit 50 in addition to the
25 output unit 20.
[0031] In the second embodiment, the DO signal outputted
from the output unit 20 of the RIO device 1a is used as a
first signal, and the DI signal inputted to the input unit
50 of the RIO device 1a is used as a second signal. In
30 addition, a detection result outputted from the readback
circuit 23 to the controller 10a is used as a first
detection result, and the detection result outputted from
the feedback circuit 51 to the controller 10a is a second
1 5
detection result. The controller 10a acquires the first
detection results that are detected by the readback circuit
23 from the readback circuit 23 when making a signal stop
request and a signal output request to the output unit 20.
5 The controller 10a also acquires the second detection
results that are detected by the feedback circuit 51 from
the feedback circuit 51 when making the signal stop request
and the signal output request to the output unit 20. Using
the first detection results and second detection results
10 each acquired, the controller 10a detects abnormality of
the output unit 20.
[0032] A description is provided next of an abnormality
detection process of the RIO device 1a. FIG. 7 is a
flowchart illustrating the abnormality detection process of
15 the RIO device 1a according to the second embodiment. FIG.
8 illustrates signal output states of the constituent
elements of the RIO device 1a according to the second
embodiment. Top three rows in FIG. 8 have different step
characters but are substantially the same as those in FIG.
20 3. Illustrated in a bottom row of FIG. 8 is a detection
result of the feedback circuit 51, that is, a signal
outputted from the feedback circuit 51. As illustrated in
the bottom row of FIG. 8, the detection result of the
feedback circuit 51 takes on either one of values that
25 represent two levels including a low (L) level and a high
(H) level. The low (L) level indicates no signal being
outputted from the relay 2a, that is, no DI signal being
inputted. The high (H) level indicates a signal being
outputted from the relay 2a, that is, a DI signal being
30 inputted.
[0033] Processes of step S201 to step S203 are
substantially the same as those of step S101 to step S103
of the first embodiment. A part for the controller 10 is
1 6
interpreted as the controller 10a, and the detection result
outputted from the readback circuit 23 to the controller
10a is interpreted as the first detection result. The same
applies to the following description. The feedback circuit
5 51 of the input unit 50 outputs to the controller 10a the
second detection result that indicates no second signal
being outputted from the relay 2a, that is, no DI signal
being inputted (step S204).
[0034] The controller 10a acquires from the readback
10 circuit 23 the first detection result obtained during the
signal stop request being made as an instruction and
acquires from the feedback circuit 51 the second detection
result obtained during the signal stop request being made
as an instruction. The controller 10a cross-checks the
15 first detection result acquired against the request made to
the output unit 20 and cross-checks the second detection
result acquired against the request made to the output unit
20 (step S205). In the example of FIG. 8, the controller
10a has acquired the first detection result (step S203)
20 that indicates no DO signal being outputted from the output
unit 20 in response to the signal stop request (step S201).
Moreover, in the example of FIG. 8, the controller 10a has
acquired the second detection result (S204) that indicates
no DI signal being inputted to the input unit 50 in
25 response to the signal stop request (step S201). On the
basis of the above results of the cross-checks, the
controller 10a determines that the output unit 20 is normal.
[0035] Processes of step S206 to step S208 are the
substantially the same as those of step S105 to step S107
30 of the first embodiment. The feedback circuit 51 of the
input unit 50 outputs to the controller 10a the second
detection result that indicates the second signal being
outputted from the relay 2a, that is, the DI signal being
1 7
inputted (step S209).
[0036] The controller 10a acquires from the readback
circuit 23 the first detection result obtained during the
signal output request made as an instruction and acquires
5 from the feedback circuit 51 the second detection result
obtained during the signal output request made as an
instruction. The controller 10a cross-checks the first
detection result acquired against the request made to the
output unit 20 and cross-checks the second detection result
10 acquired against the request made to the output unit 20
(step S210). In the example of FIG. 8, the controller 10a
has acquired the first detection result (step S208) that
indicates the DO signal being outputted from the output
unit 20 in response to the signal output request (step
15 S206). Moreover, in the example of FIG. 8, the controller
10a has acquired the second detection result (S209) that
indicates the DI signal being inputted to the input unit 50
in response to the signal output request (step S206). On
the basis of the above results of the cross-checks, the
20 controller 10a determines that the output unit 20 is normal.
[0037] If the controller 10a determines at both step
S205 and step S210 that the output unit 20 is normal (step
S211: Yes), the controller 10a continues monitoring an
operating state of the output unit 20 through continual
25 acquisition of the first detection result from the readback
circuit 23 and continual acquisition of the second
detection result from the feedback circuit 51 after start
of operation of a train (step S212).
[0038] If the controller 10a determines at either or
30 both of steps S205 and S210 that the output unit 20 is
abnormal (step S211: No), the controller 10a controls the
breaker 40 to stop the supply of power from the control
power supply 30 to the output unit 20, so as to stop
1 8
operation of the output unit 20 (step S213). Specific
abnormal cases of the output unit 20 include a case where
at least one of the first detection result of the readback
circuit 23 and the second detection result of the feedback
5 circuit 51 is high (H) when the signal of the controller
10a is low (L) at step S205. Also included as the abnormal
case of the output unit 20 is a case where at least one of
the first detection result of the readback circuit 23 and
the second detection result of the feedback circuit 51 is
10 low (L) when the signal of the controller 10a is high (H)
at step S210. A process of step S214 is substantially the
same as that of step S112 of the first embodiment.
[0039] A description is provided next of a hardware
configuration of the RIO device 1a. The input unit 50 of
15 the RIO device 1a is a digital signal input circuit. The
rest of the configuration of the RIO device 1a is similar
to the configuration of the RIO device 1 of the first
embodiment.
[0040] As described above, according to the present
20 embodiment, the RIO device 1a is further configured to use
the second detection result of the feedback circuit 51 to
make a determination of the operating state of the output
unit 20. This enables the RIO device 1a to have improved
accuracy in determining the abnormality of the output unit
25 20 as compared with the RIO device 1 of the first
embodiment.
[0041] Third Embodiment.
A RIO device according to the third embodiment is
configured to include a plurality of output units. A
30 description is provided of differences from the first
embodiment.
[0042] FIG. 9 is a block diagram illustrating a
configuration example of the RIO device 1b according to the
1 9
third embodiment. The RIO device 1b includes a controller
10b, the output units 20a and 20b, the control power supply
30, and the breaker 40. The output units 20a and 20b each
have much the same configuration as that of the output unit
5 20 of the first embodiment illustrated in FIG. 1. This
means that each of photocouplers 21a and 21b, each of
diodes 22a and 22b, each of readback circuits 23a and 23b,
and each of photocouplers 24a and 24b are similar in
structure to the photocoupler 21, the diode 22, the
10 readback circuit 23, and the photocoupler 24, respectively.
The output units 20a and 20b of the RIO device 1b are
connected in series to each other. As illustrated in FIG.
9, a DO signal outputted from the output unit 20a is
inputted to the output unit 20b, and the DO signal
15 outputted from the output unit 20b is inputted to the relay
2. The controller 10b controls whether or not to cause the
output units 20a and 20b to output the DO signal. The
controller 10 acquires detection results from the readback
circuits 23a and 23b owned by the output units 20a and 20b
20 and detects abnormality of each of the output units 20a and
20b using the acquired detection results. In FIG. 9, the
number of output units is two, but this is an example and
thus may be three or more. In the third embodiment, the
control power supply 30 supplies power to the output units
25 20a and 20b.
[0043] A description is provided next of an abnormality
detection process of the RIO device 1b. FIG. 10 is a
flowchart illustrating the abnormality detection process of
the RIO device 1b according to the third embodiment. FIG.
30 11 illustrates signal output states of the constituent
elements of the RIO device 1b according to the third
embodiment. Illustrated in a first row of FIG. 11 is a
signal that is outputted from the controller 10b to the
2 0
output unit 20a. Illustrated in a second row of FIG. 11 is
a signal that is outputted from the controller 10b to the
output unit 20b. A third row of FIG. 11 illustrates
whether or not the DO signal is outputted from the output
5 unit 20a, and a fourth row of FIG. 11 illustrates whether
or not the DO signal is outputted from the output unit 20b.
Illustrated in a fifth row of FIG. 11 is the detection
result of the readback circuit 23a, that is, a signal
outputted from the readback circuit 23a. Illustrated in a
10 sixth row of FIG. 11 is the detection result of the
readback circuit 23b, that is, a signal outputted from the
readback circuit 23b. A low (L) signal level and a high
(H) signal level in each signal have the same indications
as those in FIG. 3.
15 [0044] When the RIO device 1b is activated, the
controller 10b makes signal output requests to the output
units 20a and 20b before operation of a train mounted with
the RIO device 1b starts (step S301). During the signal
output requests being made as instructions by the
20 controller 10b, the output units 20a and 20b output the DO
signals from the photocouplers 21a and 21b (step S302).
Moreover, the readback circuits 23a and 23b of the output
units 20a and 20b output to the controller 10b their
detection results indicating the DO signals being outputted
25 from the output units 20a and 20b (step S303).
[0045] The controller 10b obtains from the readback
circuits 23a and 23b the detection results obtained during
the signal output requests made as the instructions and
cross-checks the acquired detection results against the
30 requests made to the output units 20a and 20b (step S304).
In the example of FIG. 11, since the controller 10b has
acquired the detection results (step S303) indicating the
DO signals outputted from the output units 20a and 20b in
2 1
response to the signal output requests (step S301), the
controller 10b determines that the output units 20a and 20b
are normal.
[0046] The controller 10b selects one of two or more
5 output units, namely, the output units 20a and 20b (step
S305). In this example, the controller 10b selects the
output unit 20a. The controller 10b makes a signal stop
request to the selected output unit 20a (step S306) and
makes the signal output request to the other unselected
10 output unit 20b (step S307). During the signal stop
request made as an instruction by the controller 10b, the
selected output unit 20a does not output the DO signal from
the photocoupler 21a (step S308). During the signal output
request made as an instruction by the controller 10b, the
15 other unselected output unit 20b outputs the DO signal from
the photocoupler 21b (step S309). Moreover, the readback
circuit 23a of the selected output unit 20a outputs to the
controller 10b the detection result indicative of no DO
signal being outputted from the output unit 20a. The
20 readback circuit 23b of the other unselected output unit
20b outputs to the controller 10b the same detection result
as the readback circuit 23a (step S310).
[0047] The controller 10b acquires from the readback
circuit 23a the detection result obtained during the signal
25 stop request made to the output unit 20a as an instruction
and acquires from the readback circuit 23b the detection
result obtained during the signal output request made to
the output unit 20b as an instruction. The controller 10b
cross-checks the acquired detection results against the
30 requests made to the output units 20a and 20b (step S311).
In the example of FIG. 11, since the controller 10b has
acquired the detection results (step S310) indicating no DO
signal being outputted from the readback circuits 23a and
2 2
23b in response to the signal stop request made to the
output unit 20a (step S306), the controller 10b determines
that the RIO device 1b is normal.
[0048] Since the controller 10b has not selected all the
5 output units at step S305 (step S312: No), the controller
10b returns to a process of step S301. The RIO device 1b
executes the above-stated process from step S301 to step
S304.
[0049] The controller 10b selects one of two or more
10 output units, namely, the output units 20a and 20b (step
S305). In this example, the controller 10b selects the
output unit 20b. The controller 10b makes the signal stop
request to the selected output unit 20b (step S306) and
makes the signal output request to the other unselected
15 output unit 20a (step S307). During the signal stop
request made as an instruction by the controller 10b, the
selected output unit 20b does not output the DO signal from
the photocoupler 21b (step S308). During the signal output
request made as an instruction by the controller 10b, the
20 other unselected output unit 20a outputs the DO signal from
the photocoupler 21a (step S309). Moreover, the readback
circuit 23b of the selected output unit 20b outputs to the
controller 10b the detection result indicative of no DO
signal being outputted from the output unit 20b. The
25 readback circuit 23a of the other unselected output unit
20a outputs to the controller 10b the same detection result
as the readback circuit 23b (step S310).
[0050] The controller 10b acquires from the readback
circuit 23b the detection result obtained during the signal
30 stop request made to the output unit 20b as an instruction
and acquires from the readback circuit 23a the detection
result obtained during the signal output request made to
the output unit 20a as an instruction. The controller 10b
2 3
cross-checks the acquired detection results against the
requests made to the output units 20a and 20b (step S311).
In the example of FIG. 11, since the controller 10b has
acquired the detection results (step S310) indicating no DO
5 signal being outputted from the readback circuits 23a and
23b in response to the signal stop request made to the
output unit 20b (step S306), the controller 10b determines
that the RIO device 1b is normal.
[0051] Since the controller 10b has selected all the
10 output units at step S305 (step S312: Yes), the controller
10b proceeds to a process of step S313. If the controller
10b determines at all of steps S304 and S311 that the
output units 20a and 20b are normal (step S313: Yes), the
controller 10b continues monitoring operating states of the
15 output units 20a and 20b through continual acquisition of
the detection results from the readback circuits 23a and
23b after the start of the operation of the train (step
S314).
[0052] If the controller 10b determines at at least one
20 of step S304 and step S311 that the output unit 20a or 20b
is abnormal (step S313: No), the controller 10b controls
the breaker 40 to stop the supply of power from the control
power supply 30 to the output units 20a and 20b, so as to
stop operation of the output units 20a and 20b (step S315).
25 The controller 10b causes the display device 3 to display
that at least one of the output unit 20a and the output
unit 20b has its abnormality, or that the RIO device 1b has
the abnormality (step S316).
[0053] In the present embodiment, the two or more output
30 units 20a and 20b of the RIO device 1b are configured as an
AND circuit. In other words, when the controller 10b makes
the signal output request to all the output units 20a and
20b, the RIO device 1b outputs the DO signal to the relay 2.
2 4
On the other hand, when the controller 10b makes the signal
stop request to at least one of the output units 20a and
20b, the RIO device 1b does not output the DO signal to the
relay 2.
5 [0054] According to the present embodiment described
above, one of two or more output units is sequentially
selected one by one, so as to make the signal stop request
to each output unit. Then, based on the signal output
states of the output units and the readback circuits during
10 this request, the operating states of the output units are
determined. By so doing, when any of the output units has
the abnormality, the RIO device 1b can detect the
abnormality of that output unit.
[0055] Fourth Embodiment.
15 A RIO device according to the fourth embodiment is
configured to include a plurality of output units and an
input unit. A description is provided for differences from
the first to third embodiments.
[0056] FIG. 12 is a block diagram illustrating a
20 configuration example of the RIO device 1c according to the
fourth embodiment. The RIO device 1c is connected to the
relay 2a and the display device 3. A description is
provided for the configuration of the RIO device 1c. As
compared with the RIO device 1b of the third embodiment
25 shown in FIG. 9, the RIO device 1c has a controller 10c in
place of the controller 10b and additionally has an input
unit 50 that includes the feedback circuit 51. In the
fourth embodiment, the control power supply 30 supplies
power to the input unit 50 in addition to the output units
30 20a and 20b.
[0057] In the fourth embodiment, a DO signal outputted
from the output units 20a and 20b of the RIO device 1c is
referred to as a first signal, and a DI signal inputted to
2 5
the input unit 50 of the RIO device 1c is referred to as a
second signal. In addition, detection results outputted
from the readback circuits 23a and 23b to the controller
10c are referred to as first detection results, and a
5 detection result outputted from the feedback circuit 51 to
the controller 10c is referred to as a second detection
result. The controller 10c acquires the first detection
results detected by the readback circuits 23a and 23b from
the readback circuits 23a and 23b when making a signal stop
10 request and a signal output request to the output units 20a
and 20b. The controller 10c also acquires the second
detection result detected by the feedback circuit 51 from
the feedback circuit 51 when making the signal stop request
and the signal output request to the output units 20a and
15 20b. Using the acquired first detection results and the
acquired second detection result, the controller 10c
detects abnormality of the output unit 20a or 20b.
[0058] A description is provided next of an abnormality
detection process of the RIO device 1c. FIG. 13 is a
20 flowchart illustrating the abnormality detection process of
the RIO device 1c according to the fourth embodiment. FIG.
14 illustrates signal output states of the constituent
elements of the RIO device 1c according to the fourth
embodiment. Top six rows in FIG. 14 have different step
25 characters but are the same as those in FIG. 11.
Illustrated in a bottom row of FIG. 14 is a detection
result of the feedback circuit 51, that is, a signal
outputted from the feedback circuit 51. A low (L) signal
level and a high (H) signal level for each signal have the
30 same indications as those in FIG. 8.
[0059] Processes of step S401 to step S403 are
substantially the same as those of step S301 to step S303
of the third embodiment. A part for the controller 10b is
2 6
interpreted as the controller 10c, and detection results
outputted to the controller 10c from the readback circuits
23a and 23b are regarded as first detection results. The
same applies to the following description. The feedback
5 circuit 51 of the input unit 50 outputs to the controller
10c the second detection result that indicates the second
signal being outputted from the relay 2a, that is, the DI
signal being inputted (step S404).
[0060] The controller 10c acquires from the readback
10 circuits 23a and 23b the first detection results obtained
during the signal output requests made as instructions and
acquires from the feedback circuit 51 the second detection
result obtained during the signal output request made as an
instruction. The controller 10c cross-checks the required
15 first detection results against the requests made to the
output units 20a and 20b and cross-checks the acquired
second detection result against the requests made to the
output units 20a and 20b (step S405). In the example of
FIG. 14, the controller 10c has acquired the first
20 detection results (step S403) that indicate the DO signals
being outputted from the output units 20a and 20b in
response to the signal output requests (step S401).
Moreover, in the example of FIG. 14, the controller 10c has
acquired the second detection result (step S404) that
25 indicates the DI signal being inputted to the input unit 50
in response to the signal output requests (step S401). On
the basis of the above results of the cross-checks, the
controller 10c determines that the RIO device 1c is normal.
[0061] Processes of step S406 to step S411 are
30 substantially the same as those of step S305 to step S310
in a first round of the third embodiment. The feedback
circuit 51 of the input unit 50 outputs to the controller
10c the second detection result that indicates no second
2 7
signal being outputted from the relay 2a, that is, no DI
signal being inputted (step S412).
[0062] The controller 10c acquires from the readback
circuit 23a the detection result obtained during the signal
5 stop request made to the output unit 20a as an instruction
and acquires from the readback circuit 23b the detection
result obtained during the signal output request made to
the output unit 20b as an instruction. The controller 10c
acquires from the feedback circuit 51 the second detection
10 result obtained while the signal stop request and the
signal output request are made as instructions to the
output units 20a and 20b, respectively. The controller 10c
cross-checks the acquired first detection results against
the requests made to the output units 20a and 20b and
15 cross-checks the acquired second detection result against
the requests made to the output units 20a and 20b (step
S413). In the example of FIG. 14, the controller 10c has
acquired the first detection results (step S411) that
indicate no DO signal being outputted from the output units
20 20a and 20b in response to the signal stop request (step
S407). Moreover, in the example of FIG. 14, the controller
10c has acquired the second detection result (step S412)
that indicates no DI signal being inputted to the input
unit 50 in response to the signal stop request (step S407)
25 made to the output unit 20a. On the basis of the above
results of the cross-checks, the controller 10c determines
that the output units 20a and 20b are normal.
[0063] Since the controller 10c does not select all the
output units at step S406 (step S414: No), the controller
30 10c returns to a process of step S401. The RIO device 1c
executes the above-stated process from step S401 to step
S405. The RIO device 1c executes a process similar to a
process of steps S305 to S310 in a second round of the
2 8
third embodiment in the subsequent steps S406 to S411. The
feedback circuit 51 of the input unit 50 outputs to the
controller 10c the second detection result that indicates
no second signal being outputted from the relay 2a, that is,
5 no DI signal being inputted (step S412).
[0064] The controller 10c obtains from the readback
circuit 23b the detection result obtained during the signal
stop request made to the output unit 20b as an instruction
and obtains from the readback circuit 23a the detection
10 result obtained during the signal output request made to
the output unit 20a as an instruction. The controller 10c
obtains from the feedback circuit 51 the second detection
result obtained while the signal stop request and the
signal output request are made as instructions to the
15 output units 20b and 20a, respectively. The controller 10c
cross-checks the obtained first detection results against
the requests made to the output units 20a and 20b and
cross-checks the obtained second detection result against
the requests made to the output units 20a and 20b (step
20 S413). In the example of FIG. 14, the controller 10c has
acquired the first detection results (step S411) that
indicate no DO signal being outputted from the output units
20a and 20b in response to the signal stop request (step
S407) made to the output unit 20b. Moreover, in the
25 example of FIG. 14, the controller 10c has acquired the
second detection result (step S412) that indicates no DI
signal being inputted to the input unit 50 in response to
the signal stop request (step S407) made to the output unit
20b. On the basis of the above results of the cross-checks,
30 the controller 10c determines that the RIO device 1c is
normal.
[0065] Since the controller 10c has selected all the
output units at step S406 (step S414: Yes), the controller
2 9
10c proceeds to a process of step S415. If the controller
10c determines at all of steps S405 and S413 that the
output units 20a and 20b are normal (step S415: Yes), the
controller 10c continues monitoring operating states of the
5 output units 20a and 20b through continual acquisition of
the first detection results from the readback circuits 23a
and 23b and continual acquisition of the second detection
result from the feedback circuit 51 after start of
operation of a train (step S416).
10 [0066] If the controller 10c determines at at least one
of step S405 and step S413 that the output unit 20a or 20b
is abnormal (step S415: No), the controller 10c controls
the breaker 40 to stop the supply of power from the control
power supply 30 to the output units 20a and 20b, so as to
15 stop operation of the output units 20a and 20b (step S417).
The controller 10c causes the display device 3 to display
that at least one of the output unit 20a and the output
unit 20b has a failure, or abnormality has occurred in the
RIO device 1c (step S418).
20 [0067] According to the present embodiment described
above, the RIO device 2 is configured to further use the
second detection result of the feedback circuit 51 to
determine how the operating states of the output units 20a
and 20b are. This enables the RIO device 1c to have
25 improved accuracy in determining the abnormalities of the
output units 20a and 20b as compared with the RIO device 1b
of the third embodiment.
[0068] The above configurations illustrated in the
embodiments are examples of contents of the present
30 invention, and can be combined with other publicly known
techniques and each partially omitted and/or modified
without departing from the gist of the present invention.
3 0
Reference Signs List
[0069] 1, 1a, 1b, 1c RIO device; 2, 2a relay; 3
display device; 10, 10a, 10b, 10c controller; 20, 20a, 20b
output unit; 21, 21a, 21b, 24, 24a, 24b, 52 photocoupler;
5 22, 22a, 22b diode; 23, 23a, 23b readback circuit; 30
control power supply; 40 breaker; 50 input unit; 51
feedback circuit.
3 1
We Claim:
1. A signal control device mounted to a train, the signal
control device comprising:
5 an output unit to output a signal to an external
device mounted to the train; and
a controller to control whether or not to cause the
output unit to output the signal, wherein
the output unit includes a readback circuit to detect
10 whether or not the signal is outputted from the output unit,
and
the controller makes a signal stop request and a
signal output request to the output unit before operation
of the train starts, acquires a detection result of the
15 readback circuit while each of the signal stop request and
the signal output request is performed, and detects
abnormality of the output unit using the detection result.
2. The signal control device according to claim 1,
20 wherein
the signal outputted from the output unit is used as a
first signal, while the detection result of the readback
circuit is used as a first detection result,
the signal control device further comprises a feedback
25 circuit to detect a second signal indicative of an
operating state of the external device to which the first
signal is inputted, and
the controller acquires a second detection result of
the feedback circuit while each of the signal stop request
30 and the signal output request is performed and detects
abnormality of the output unit using the first detection
result and the second detection result.
3 2
3. The signal control device according to claim 1 or 2,
wherein
the controller stops supply of power to the output
unit when abnormality of the output unit is detected.
5
4. The signal control device according to claim 3,
wherein
the controller causes a display device to display that
abnormality of the output unit is detected.
10
5. The signal control device according to claim 1,
comprising two or more output units each equal in
configuration to the output unit, wherein
the controller makes the signal stop request and the
15 signal output request to the output units before operation
of the train starts, acquires detection results of two or
more readback circuits while each of the signal stop
request and the signal output request is performed, and
detects abnormality of any of the output units using two or
20 more detection results.
6. The signal control device according to claim 5,
wherein
the signal outputted from each of the output units is
25 used as a first signal, while the detection results of the
readback circuits are used as first detection results,
the signal control device further comprises a feedback
circuit to detect a second signal indicative of an
operating state of the external device to which the first
30 signal is inputted, and
the controller acquires a second detection result of
the feedback circuit while each of the signal stop request
and the signal output request is performed, and detects
3 3
abnormality of any of the output units using two or more
first detection results and the second detection result.
7. The signal control device according to claim 5 or 6,
5 wherein
the controller stops supply of power to the output
units when abnormality is detected in any of the output
units.
10 8. The signal control device according to claim 7,
wherein
the controller causes a display device to display that
abnormality is detected in any of the output units.
15 9. An abnormality detection method in a signal control
device mounted to a train, the abnormality detection method
comprising:
a first step of a controller making a signal stop
request and a signal output request to an output unit
20 before operation of the train starts;
a second step of the output unit outputting or
stopping a signal to an external device mounted to the
train in accordance with a request of the controller;
a third step of a readback circuit owned by the output
25 unit detecting whether or not the signal is outputted from
the output unit; and
a fourth step of the controller acquiring a detection
result of the readback circuit while each of the signal
stop request and the signal output request is performed and
30 detecting abnormality of the output unit using the
detection result.
10. The abnormality detection method according to claim 9,
3 4
wherein the signal outputted from the output unit is used
as a first signal, while the detection result of the
readback circuit is used as a first detection result,
the abnormality detection method further comprises a
5 fifth step of a feedback circuit detecting a second signal
indicative of an operating state of the external device to
which the first signal is inputted, and
in the fourth step, the controller acquires a second
detection result of the feedback circuit while each of the
10 signal stop request and the signal output request is
performed, and detects abnormality of the output unit by
using the first detection result and the second detection
result.
15 11. The abnormality detection method according to claim 9
or 10, further comprising a sixth step of the controller
stopping supply of power to the output unit when
abnormality of the output unit is detected.
20 12. The abnormality detection method according to claim 11,
further comprising a seventh step of the controller causing
a display device to display that abnormality of the output
unit is detected.
25 13. The abnormality detection method according to claim 9,
wherein
the signal control device includes two or more output
units each equal in configuration to the output unit,
in the first step, the controller makes the signal
30 stop request and the signal output request to the output
units before operation of the train starts,
in the second step, the output units each output or
stop the signal in accordance with a request of the
3 5
controller,
in the third step, each of readback circuits owned by
the output units detects whether or not the signal is
outputted from the output unit, and
5 in the fourth step, the controller acquires detection
results of the readback circuits while each of the signal
stop request and the signal output request is performed,
and detects abnormality of any of the output units using
two or more detection results.
10
14. The abnormality detection method according to claim 13,
wherein
the signal outputted from each of the output units is
used as a first signal, while the detection results of the
15 readback circuits are used as first detection results,
the abnormality detection method further comprises a
fifth step of a feedback circuit detecting a second signal
indicative of an operating state of the external device to
which the first signal is inputted, and
20 in the fourth step, the controller acquires a second
detection result of the feedback circuit while each of the
signal stop request and the signal output request is
performed, and detects abnormality of any of the output
units using two or more first detection results and the
25 second detection result.
15. The abnormality detection method according to claim 13
or 14, further comprising a sixth step of the controller
stopping supply of power to the output units when
30 abnormality is detected in any of the output units.
16. The abnormality detection method according to claim 15,
further comprising a seventh step of the controller causing
3 6
a display device to display that abnormality is detected in
any of the output units.