Axle detection device

Abstract

To improve safety by controlling to the safe side in the event of an axle sensor failure. [Solution] The axle detection device 10 includes axle sensors 15 that detect the axles of trains passing at each end of the detection target section DT, an on-track presence determination unit 35 that determines whether each train is on track in the detection target section DT based on the detection results of the two axle sensors 15 that are positioned so that each train enters and exits the detection target section DT, a failure determination unit 40 that determines a failure of the two axle sensors 15 based on the detection results of the two axle sensors 15 and the on-track / off-track determination results of two adjacent sections AD close to the two axle sensors 15, and a control unit 45 that controls the entire device 10, and when a failure of an axle sensor 15 is detected, the control unit 45 controls the on-track presence determination unit 35 to determine that a train is on track in the detection target section DT. This allows for safe control even if the axle sensor 15 fails, thereby improving the safety of the axle detection device 10.

Description

[Technical Field]

[0001] The present invention relates to an axle detection device that detects the axles of a train and determines whether the train is on the rail or not. [Background technology]

[0002] A railway axle detection device counts the number of axles passing on the rails on the approaching and departing sides using an axle sensor, and detects the presence or absence of a train within a controlled section from the axle count value of the axle sensor. The presence of a train is detected from the difference between the axle count value on the approaching side and the axle count value on the departing side (see, for example, Patent Document 1). To use such an axle detection device as a safety device, it is necessary to detect a failure or abnormality in each part of the device and control the device to a safe side (to keep the device in a state where a train is detected within the controlled section), and not to perform dangerous operations in the event of a failure (to determine that a train is not present on the track even though the train is entering the controlled section). Patent Document 2 discloses technology related to detecting axle sensor failures. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-131084 [Patent Document 2] Japanese Patent Publication No. 2020-075540 Summary of the Invention [Problem to be solved by the invention]

[0004] To confirm whether a conventional axle detection device fulfills the requirements for safety, a breakdown analysis was conducted by breaking down the functions and circuits of the device. It was found that when an axle sensor fails to detect an axle, it may determine that a train is not present within the control section (a dangerous event) even when a train is present within the control section. Specifically, axle sensors have two failure modes: a failure that causes the sensor to continue to detect the axle and a failure that causes the sensor to no longer detect the axle. When a failure occurs in the sensor that continues to detect the axle, safety control (i.e., a train is present on the track) can be achieved, but when a failure occurs in the sensor that causes the sensor to no longer detect the axle, the axle detection device cannot detect the failure. In particular, when an axle sensor installed on the approach side fails to detect the axle, it may mistakenly determine that a train is not present within the control section of the axle detection device, even when a train is present within the control section. This poses a major challenge when using axle detection devices as safety devices.

[0005] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to improve safety by controlling to the safe side when an axle sensor fails. [Means for solving the problem]

[0006] (Aspects of the invention) The following embodiments of the present invention are examples of the configuration of the present invention, and are described in terms to facilitate understanding of the various configurations of the present invention. Each term does not limit the technical scope of the present invention, and while taking into consideration the best mode for carrying out the invention, some of the components of each term may be replaced or deleted, or other components may be added, and these may also be included in the technical scope of the present invention.

[0007] (1) An axle detection device that detects the axles of a train and determines whether a train is on the track or not in a detection target section set between at least two adjacent sections that determine whether a train is on the track or not using a track circuit system, and that determines whether a train is on the track or not by detecting the axles of a train in the detection target section, using the detection results of at least two axle sensors that detect the axles of a train passing through each end of the track in the detection target section, and two of the at least two axle sensors that are in a positional relationship where the train enters and exits the detection target section according to the progress of each train. a fault determination unit that determines a fault in the two axle sensors based on the detection results of the two axle sensors and the results of determining whether a train is present on the track in two adjacent sections that are close to the two axle sensors among the at least two adjacent sections; and a control unit that controls the entire device, wherein the control unit controls the track presence determination unit to determine that a train is present on the track in the detection target section when the fault determination unit determines that one of the axle sensors has failed.

[0008] The axle detection device described in this section determines whether a train is present on a track in a detection target section established between at least two adjacent sections where the presence / absence of a train is determined using a track circuit system, and includes at least two axle sensors, a track presence determination unit, a fault determination unit, and a control unit. The at least two axle sensors detect the axles of trains passing through each end of the track in the detection target section. If the detection target section is between two adjacent sections, at least one axle sensor is installed at one end of the track in the detection target section facing the adjacent section, and at least one axle sensor is installed at the other end of the track in the detection target section facing the adjacent section. On the other hand, if one side of the track in the detection target section is bifurcated and the detection target section is adjacent to three adjacent sections where the presence / absence of a train is determined using a track circuit system, at least one axle sensor is installed at each of the three ends of the track in the detection target section.

[0009] The track presence determination unit uses the detection results of the axle sensors to determine whether a train is present in the target detection section. The track presence determination unit makes its determination using the detection results of two of the at least two axle sensors, which are positioned so that the train approaches and exits the target detection section as the train progresses. That is, if the target detection section is located between two adjacent sections, the axle sensor on one of the adjacent sections serves as the approach-side axle sensor, and the axle sensor on the other adjacent section serves as the exit-side axle sensor, and the detection results of these two axle sensors are used. Even if the target detection section is adjacent to three adjacent sections, the detection results of the two axle sensors installed at each of the three ends of the track in the target detection section, which are positioned so that the train approaches and exits, are used. The track presence determination unit then compares the detection results of the approach-side axle sensor with those of the exit-side axle sensor to determine whether a train is present in the target detection section between them.

[0010] The failure determination unit determines whether an axle sensor has failed by using the axle sensor detection results and the track circuit system's train presence / absence determination results for adjacent sections. At this time, the detection results of the axle sensors are used, as the axle sensor detection results, for the two axle sensors that are in the positional relationship where each train approaches and exits the detection target section as described above. Furthermore, as the adjacent section determination results, the unit uses the train presence / absence determination results for two adjacent sections close to (adjacent to) the two axle sensors, i.e., the adjacent section close to the approaching axle sensor and the adjacent section close to the exiting axle sensor.

[0011] The failure determination unit determines that one or both of the two axle sensors are faulty when a discrepancy occurs between the estimated presence / absence in the detection target section, which is estimated from the presence / absence determination result of the adjacent section, and the train axle detection results by each of the two axle sensors. For example, the failure determination unit determines that the approaching axle sensor is faulty when the approaching axle sensor does not detect the axle of a train entering the detection target section, even though it is estimated that a train has entered the detection target section based on the presence / absence determination result of the adjacent section close to the approaching axle sensor. This ensures that a failure on the side of the axle sensor that makes it unable to detect axles is detected.

[0012] The control unit controls the entire axle detection device and controls each component of the axle detection device as needed. As one example of such control, when the failure determination unit determines that one of the axle sensors has failed, the control unit controls the track presence determination unit to determine that a train is present in the target detection section. This ensures safety by determining that a train is present in the target detection section regardless of whether the axle sensor has failed in either the mode that causes it to continue to detect the axle or the mode that causes it to no longer be able to detect the axle, thereby improving the safety of the axle detection device. Furthermore, the above-described axle sensor failure determination for such control can be achieved by incorporating the results of a track circuit-based train presence determination in an adjacent section, thereby simplifying the device configuration and reducing costs.

[0013] (2) In the above paragraph (1), the axle detection device further includes a counting unit that counts the number of axles detected by each of the at least two axle sensors, and the on-track determination unit compares the count results of the two axle sensors by the counting unit, and determines that a train is not on the track in the detection target section if the count result of the approaching axle sensor located on the side where the train enters the detection target section and the count result of the outgoing axle sensor located on the side where the train leaves the detection target section are equal, and determines that a train is on the track in the detection target section if the count result of the approaching axle sensor is greater than the count result of the outgoing axle sensor.

[0014] The axle detection device described in this section further includes a counting unit that counts the number of axles of a train passing through each end of the track in the detection target section, as detected by each of the at least two axle sensors. The on-track determination unit compares the count results of two of the at least two axle sensors that are positioned so that each train approaches and exits the detection target section. If the count result of the approaching axle sensor located on the side where the train approaches the detection target section is equal to the count result of the outgoing axle sensor located on the side where the train exits the detection target section, the device determines that a train is not present in the detection target section. This determination is based on the fact that even if the count value of the approaching axle sensor increases as the train enters the detection target section, the count values ​​of the outgoing axle sensor will always be equal if the train has already exited the detection target section and the count value of the entering axle sensor has increased.

[0015] Furthermore, the on-track determination unit determines that a train is present in the detection target section when the count result of the approaching axle sensor is greater than the count result of the outgoing axle sensor. This determination is based on the fact that if a train enters the detection target section and the count value of the approaching axle sensor increases, and if the train is still present in the detection target section and the count value of the outgoing axle sensor has not increased, the count value of the approaching axle sensor will be greater than that of the outgoing axle sensor. This allows for more accurate determination of whether a train is present on the track in the detection target section.

[0016] (3) In the above paragraph (2), the failure determination unit determines that the approaching axle sensor is faulty when the counting result of the approaching axle sensor by the counting unit does not increase even though it is determined that a train has changed from being present on the track to not being present on the track in the approaching adjacent section of the two adjacent sections that is close to the approaching axle sensor, and determines that the approaching axle sensor or the outgoing axle sensor is faulty when the counting results of the two axle sensors by the counting unit are not equal even though it is determined that a train has changed from being present on the track to not being present on the track in the outgoing adjacent section of the two adjacent sections that is close to the outgoing axle sensor.

[0017] The axle detection device described in this section specifies the conditions for the failure determination unit to determine a failure of the axle sensor as follows: That is, the failure determination unit determines that the approach-side axle sensor has failed when the count result of the approach-side axle sensor by the counting unit does not increase even though the track circuit system determines that a train has changed from being present on the track to being absent in the approach-side adjacent section close to (adjacent to) the approach-side axle sensor. This means that if a train has changed from being present on the track to being absent in the approach-side adjacent section, it is presumed that the train has entered the detection target section from the approach-side adjacent section, but the approach-side axle sensor has not detected the axle of the train entering the detection target section, so it determines that the approach-side axle sensor has failed.

[0018] Furthermore, the failure determination unit determines that the approaching axle sensor or the outgoing axle sensor is faulty when the counting unit's counting results of the approaching axle sensor and the outgoing axle sensor are not equal, even though the track circuit system has determined that a train has changed from being present on the track to being absent in the outgoing adjacent section close to (adjacent to) the outgoing axle sensor. This is because if a train has changed from being present on the track to being absent in the outgoing adjacent section, it is assumed that the train has already left the detection target section and entered the outgoing adjacent section (and also exited from the outgoing adjacent section), and the counting results of the approaching axle sensor and the outgoing axle sensor should be equal. However, since these counting results are not equal, it is determined that the approaching axle sensor or the outgoing axle sensor is faulty. This allows for more accurate detection of failures in the approaching axle sensor and the outgoing axle sensor.

[0019] (4) In paragraph (3) above, the approach-side adjacent section is adjacent to a second adjacent section, on the side opposite to the detection target section, which uses a track circuit system to determine whether a train is present on the line or not, and the fault determination unit does not determine that the approach-side axle sensor is faulty if it can be confirmed from the train presence / absence determination result in the second adjacent section that the train has returned from the approach-side adjacent section to the second adjacent section, even if the count result of the approach-side axle sensor by the counting unit does not increase even though it has been determined that the train has changed from present on the line to not present on the line in the approach-side adjacent section.

[0020] The axle detection device described in this section utilizes not only the results of train presence determination in the adjacent section adjacent to the detection target section, but also the results of train presence determination in the second adjacent section using a track circuit system, which is adjacent to the side of the adjacent section opposite the side adjacent to the detection target section. That is, if the count result of the approach-side axle sensor by the counting unit does not increase even though it is determined that a train has changed from being present on the track in the approach-side adjacent section, the failure determination unit determines that the approach-side axle sensor is faulty, as mentioned in section (3) above. However, even in such a case, if the failure determination unit can confirm that the train has returned from the approach-side adjacent section to the second adjacent section based on the train presence / absence determination result in the second adjacent section adjacent to the approach-side adjacent section, it will not determine that the approach-side axle sensor is faulty.

[0021] This means that when a train goes from being present on the track to being absent on the track in the approach-side adjacent section, it is assumed that the train has not only entered the detection target section from the approach-side adjacent section, but also returned from the approach-side adjacent section to the second adjacent section. If this can be confirmed from the determination result of the second adjacent section, the failure determination unit does not determine that the approach-side axle sensor is faulty. In other words, if the count result of the approach-side axle sensor by the counting unit does not increase even though it has been determined that the train has gone from being present on the track to being absent on the track in the approach-side adjacent section, and it cannot be confirmed from the determination result of the second adjacent section that the train has returned from the approach-side adjacent section to the second adjacent section, the failure determination unit determines that the approach-side axle sensor is faulty. This avoids false detection of a failure in the approach-side axle sensor, and further improves the accuracy of detecting axle sensor failures.

[0022] (5) In the above paragraph (2), when the control unit can confirm that a train has changed from being present on the track to being absent on the track in the detection target section from the train presence / absence determination result in the incoming adjacent section, which is closest to the incoming axle sensor, of the two adjacent sections, the control unit causes the on-track determination unit to determine that a train is not present on the track in the detection target section even if the difference between the count results of the two axle sensors by the counting unit is 1, and adjusts the count results of the two axle sensors by the counting unit so that they are equal.

[0023] The axle detection device described in this section is designed to deal with the possibility that axles may not be counted properly if a pebble or other foreign object on the rail causes the train's axle to float above the axle sensor, and performs the following control to address this issue. Such axle floating rarely occurs consecutively, and it is also rare for it to occur simultaneously on both the approaching and exiting axle sensors. Therefore, even if an axle floating occurs, it is expected that one count will not be performed on either the approaching or exiting axle sensor.

[0024] Therefore, the control unit checks whether a train has changed from being present on the track to being absent on the track in the detection target section based on the train presence / absence determination results of the track circuit system in the outgoing-side adjacent section close to the outgoing-side axle sensor. If it is determined that a train has changed from being present on the track to being absent on the track in the detection target section, the control unit determines that an axle lift has occurred, rather than a train being present on the track or an axle sensor malfunction, even if the count results of the ingoing-side axle sensor and the outgoing-side axle sensor count results by the counting unit are not equal, if the difference between these count results is 1. The control unit then controls the track presence determination unit to determine that a train is not present on the track in the detection target section, and adjusts the count results of the two axle sensors by incrementing or decrementing one count result by 1 or resetting both count results so that the count results of the two axle sensors are equal. This prevents axle lift from continuing to determine that a train is present on the track or from erroneously detecting an axle sensor malfunction, thereby reducing the impact on train operations.

[0025] (6) In the above paragraph (1), the control unit is an axle detection device that determines the direction of travel of the train by utilizing the detection results of the at least two axle sensors and the determination results of whether the train is on the track or not in the at least two adjacent sections. The axle detection device described in this section determines the direction of travel of a train by utilizing the detection results of at least two axle sensors installed at each end of the track in the detection target section and the determination results of whether a train is present on the track or not in at least two adjacent sections of a track circuit system adjacent to the detection target section.

[0026] That is, when it is confirmed that a train has changed from being present on the tracks to not being present on the tracks in a certain adjacent section, and at almost the same time an axle is detected by an axle sensor installed at the end of the certain adjacent section, the control unit determines that the train is proceeding from the certain adjacent section toward the detection target section. Also, when an axle is detected by an axle sensor installed at the end of the certain adjacent section, and at almost the same time it is confirmed that a train has changed from not being present on the tracks to being present on the tracks in the certain adjacent section, the control unit determines that the train is proceeding from the detection target section toward the certain adjacent section. This makes it easy to determine the direction of travel of the train, thereby enabling more accurate determination of whether the train is present on the tracks or not, and determination of a fault in the axle sensor. [Effects of the Invention]

[0027] With the above-described configuration, the present invention can improve safety by controlling the vehicle to the safe side when an axle sensor fails. [Brief explanation of the drawings]

[0028] [Figure 1] 1 is a block diagram illustrating an example of the configuration of an axle detection device according to an embodiment of the present invention. [Figure 2] 2 is a flowchart showing an example of the operation of the axle detection device of FIG. 1. [Figure 3] 2, is a flowchart showing an example of the operation of the axle detection device of FIG. [Figure 4] 2 is an image diagram showing how the position of a train changes, for explaining the operation of the axle detection device of FIG. 1. FIG. [Figure 5] Continuing from FIG. 4, this is an image diagram showing how the position of a train changes, for explaining the operation of the axle detection device of FIG. [Figure 6] 5, is an image diagram showing how the position of a train changes, for explaining the operation of the axle detection device of FIG. [Figure 7] 2 is an image diagram illustrating a section of a railway track different from that in FIG. 1 in which an axle detection device according to an embodiment of the present invention is installed. DETAILED DESCRIPTION OF THE INVENTION

[0029] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Here, detailed descriptions of parts that are the same as or corresponding to those in the prior art will be omitted, and the same reference numerals will be used throughout the drawings to indicate the same or corresponding parts. Fig. 1 shows a schematic diagram of an example of the configuration of an axle detection device 10 according to an embodiment of the present invention. This axle detection device 10 detects the axles of a train 50 in a detection target section DT that is set between at least two adjacent sections AD that use a track circuit system to determine whether the train 50 is present on the rail (see Figs. 4 to 6). The detection target section DT shown in Fig. 1 is set between two adjacent sections AD that are at least two adjacent sections AD, and one of the adjacent sections AD (on the left side in the figure) is adjacent to a second adjacent section AD2 that uses a track circuit system to determine whether the train 50 is present on the rail.

[0030] As shown in Fig. 1, an axle detection device 10 according to an embodiment of the present invention includes an axle sensor 15, an evaluation unit 25, a counting unit 30, a track presence determination unit 35, a fault determination unit 40, and a control unit 45. Of these, the evaluation unit 25, the counting unit 30, the track presence determination unit 35, the fault determination unit 40, and the control unit 45, excluding the axle sensor 15, are configured in a data processing unit 20 in this embodiment. The axle sensors 15 detect the axles of trains 50 passing through each end of the track in the detection target section DT, and in the embodiment of Fig. 1 in which the detection target section DT is between two adjacent sections AD, at least two axle sensors 15 are installed.

[0031] That is, at least one axle sensor 15 is installed near the end of the detection target section DT to detect the axles of the train 50 passing through the end of the adjacent section AD on the left side of the figure. Furthermore, at least one axle sensor 15 is also installed near the end of the detection target section DT to detect the axles of the train 50 passing through the end of the adjacent section AD on the right side of the figure. For ease of explanation, it is assumed here that one axle sensor 15 (15A) is installed near the end of the detection target section DT on the left side of the figure, and one axle sensor 15 (15B) is installed near the end of the detection target section DT on the right side of the figure. Furthermore, in order to avoid false detection of a fault in the axle sensor 15 as described below, the installation position of each axle sensor 15 is assumed to be within the length of one train set of the train 50 from the corresponding adjacent section AD.

[0032] The evaluation unit 25 determines the presence or absence of axles on the train 50 based on the electrical signals output by the axle sensors 15. In this embodiment, two evaluation units 25 are provided to perform separate evaluations for the two axle sensors 15A and 15B. While the axle sensor 15 in FIG. 1 transmits axle detection results via electrical signals, any sensor used in conventional axle detection devices may be used for each axle sensor 15 in the axle detection device 10 according to the embodiment of the present invention. The count unit 30 counts the number of axles detected by each axle sensor 15 based on the determination results of each evaluation unit 25. In this embodiment, the count unit 30 counts the number of axles detected by each of the two axle sensors 15A and 15B. That is, each time an axle is detected by each axle sensor 15, the count value of that axle sensor 15 is incremented by one.

[0033] The track presence determination unit 35 determines whether a train 50 is present in the detection target section DT using the detection results of the axle sensors 15. More specifically, the track presence determination unit 35 makes its determination using the detection results of two axle sensors 15, among those installed in the detection target section DT, that are positioned so that the train 50 approaches and leaves the detection target section DT as the train 50 travels. In this embodiment, two axle sensors 15A and 15B are installed, and therefore, depending on the traveling direction of the train 50, one of them serves as the approaching axle sensor 15, and the other serves as the leaving axle sensor 15. Hereinafter, unless otherwise noted, the train 50 is assumed to travel from left to right in FIG. 1, and the axle sensor 15A on the left side in the figure will also be referred to as the approaching axle sensor 15A, and the axle sensor 15B on the right side in the figure will also be referred to as the leaving axle sensor 15B. In this case, the on-track determining unit 35 determines whether the train 50 is on track in the detection target section DT using the axle detection results from the incoming axle sensor 15A and the axle detection results from the outgoing axle sensor 15B.

[0034] More specifically, the track presence determination unit 35 compares the count result of the approaching axle sensor 15A and the count result of the outgoing axle sensor 15B, which are obtained by the counting unit 30. In FIG. 1, the input of these count results is indicated by an arrow extending from the counting unit 30 to the track presence determination unit 35. If the count result of the approaching axle sensor 15A and the count result of the outgoing axle sensor 15B are equal, the track presence determination unit 35 determines that the train 50 is not present in the detection target section DT. Furthermore, if the count result of the approaching axle sensor 15A is greater than the count result of the outgoing axle sensor 15B, the track presence determination unit 35 determines that the train 50 is present in the detection target section DT. The method by which the track presence determination unit 35 determines that the train 50 is present on the track will be explained in more detail later.

[0035] The fault determination unit 40 determines whether there is a fault in the two axle sensors 15 located at positions where the train 50 approaches and exits the detection target section DT, i.e., the approaching axle sensor 15A and the outgoing axle sensor 15B. The fault determination unit 40 uses the axle detection results of the approaching axle sensor 15A and the outgoing axle sensor 15B, the train presence / absence determination results for the two adjacent sections AD adjacent to these two axle sensors 15A and 15B, and the train presence / absence determination results for the second adjacent section AD2 as information for making the determination. The axle detection results of the approaching axle sensor 15A and the outgoing axle sensor 15B are the count results of the approaching axle sensor 15A and the outgoing axle sensor 15B by the counting unit 30. In FIG. 1 , the input of these count results is indicated by arrows extending from the counting unit 30 to the fault determination unit 40.

[0036] In addition, in FIG. 1, in which the train 50 is shown traveling from left to right in the figure, the adjacent section AD adjacent to the incoming axle sensor 15A is the adjacent section AD on the left in the figure, which will hereinafter also be referred to as the incoming adjacent section ADin. Similarly, in FIG. 1, the adjacent section AD adjacent to the outgoing axle sensor 15B is the adjacent section AD on the right in the figure, which will hereinafter also be referred to as the outgoing adjacent section ADout. As described above, the second adjacent section AD2 is the section adjacent to the left adjacent section AD on the opposite side of the detection target section DT; in other words, it is adjacent to the incoming adjacent section ADin. In FIG. 1, the input of the train 50 presence / absence determination results for each of the adjacent sections ADin, ADout, and AD2 is shown by arrows labeled "adjacent section determination result," "adjacent section determination result," and "second adjacent section determination result" extending to the fault determination unit 40. The judgment results for each of these adjacent sections ADin, ADout, and AD2 may be, for example, the contact conditions of the output relays of the track circuits of each adjacent section, but are not limited to relays and may be other alternative means as long as safety is ensured.

[0037] The failure determination unit 40 uses the above-mentioned input information to determine whether the approach-side axle sensor 15A and the outgoing-side axle sensor 15B have a failure, for example, as follows: First, when it is determined that the train 50 has changed from being present on the track to being absent in the approach-side adjacent section ADin, but the count result of the approach-side axle sensor 15A by the counting unit 30 does not increase, the failure determination unit 40 determines that the approach-side axle sensor 15A has a failure. However, even in such a case, if it is possible to confirm that the train 50 has returned from the approach-side adjacent section ADin to the second adjacent section AD2 based on the presence / absence determination result of the train 50 in the second adjacent section AD2, the failure determination unit 40 does not determine that the approach-side axle sensor 15A has a failure.

[0038] Furthermore, if it is determined that the train 50 has changed from being present on the track to being absent on the track in the outgoing adjacent section ADout, but the counting results of the ingoing axle sensor 15A and the outgoing axle sensor 15B by the counting unit 30 are not equal, the failure determination unit 40 determines that the ingoing axle sensor 15A or the outgoing axle sensor 15B has failed. The method of determining a failure of the axle sensor 15 by the failure determination unit 40 will be explained in more detail later. The train presence determination result of the train 50 in the detection target section DT by the track presence determination unit 35 and the failure determination result of the axle sensor 15 by the failure determination unit 40 are output from the data processing unit 20, for example, as signals that drive relays that output these determination results. In this case, the train presence determination result of the train 50 and the failure determination result of the axle sensor 15 are output from each of the relays (not shown).

[0039] The control unit 45 controls the entire axle detection device 10 and performs the following control as necessary. Specifically, when the failure determination unit 40 determines that one of the axle sensors 15 has failed, the control unit 45 controls the on-track determination unit 35 to determine that the train 50 is present in the detection target section DT. Furthermore, when a discrepancy occurs between the counting results of the approaching axle sensor 15A and the outgoing axle sensor 15B by the counting unit 30, which is presumably due to axle lift caused by a foreign object such as a pebble on the rail, the control unit 45 controls the determination result of the on-track determination unit 35 and adjusts the counting result of the counting unit 30. Furthermore, the control unit 45 determines the traveling direction of the train 50 using the detection results of each axle sensor 15 and the on-track / off-track determination results of the train 50 in each adjacent section AD. The control unit 45 also mediates data exchange between the components of the data processing unit 20. The specific control content of the control unit 45 will be described in more detail later.

[0040] The configuration of the axle detection device 10 according to the embodiment of the present invention is not limited to the block diagram of Fig. 1, and may be configured such that some of the components shown in Fig. 1 are deleted, modified, or appropriately added depending on the configuration and conditions of the railway line to which the device is applied. Also, the components of the data processing unit 20 shown in Fig. 1 are divided into functional units, and are not divided into hardware or software units that actually constitute the data processing unit 20. Furthermore, any hardware and software can be used for the hardware and software that constitute the data processing unit 20.

[0041] Next, the operation of the axle detection device 10 shown in FIG. 1 will be described in accordance with the flow diagrams shown in FIGS. 2 and 3. For the configuration of the axle detection device 10, please refer to FIG. 1 as appropriate. Note that the flow diagrams shown in FIGS. 2 and 3 show an example of a procedural flow for explaining the operation of the axle detection device 10. Therefore, the operation of the axle detection device 10 is not limited to these flow diagrams. For example, some of the steps shown in FIGS. 2 and 3 may be deleted, changed, or added as appropriate depending on the configuration and situation of the axle detection device 10. Furthermore, the flow diagram in FIG. 2 and the flow diagram in FIG. 3 are connected at connection points A and B, respectively.

[0042] Here, in the explanation following the flow diagrams shown in Figures 2 and 3, Figures 4 to 6 will be referred to as necessary. Figures 4 to 6 show a train 50 heading from station A to station B, with an approach-side adjacent section ADin, a detection target section DT, and an exit-side adjacent section ADout set between stations A and B. In these figures, the approach-side adjacent section ADin is also shown as "21T," the detection target section DT as "ABT," and the exit-side adjacent section ADout as "11T." The axle sensor 15 installed at the end of the detection target section DT on the Station A side is the approach-side axle sensor 15A, and the axle sensor 15 installed at the end of the detection target section DT on the Station B side is the exit-side axle sensor 15B. The data processing unit 20 performs on-track determination and fault determination based on the detection results of the axle sensors 15A and 15B, the determination results in the approach-side adjacent section ADin (21T), the determination results in the exit-side adjacent section ADout (11T), and the determination results in the second adjacent section AD2. Note that the determination results in the second adjacent section AD2 here are, for example, the determination results of whether a train is on track or not at station A.

[0043] S10 (check the state of the approach-side adjacent section): The fault determination unit 40 obtains the track circuit method-based determination result of whether a train is present or absent in the approach-side adjacent section ADin, and checks the state of the approach-side adjacent section ADin. S20 (Confirm count result of approaching axle sensor): The track presence determination unit 35 and the fault determination unit 40 obtain the count result of the axles of the train 50 counted by the counting unit 30 at the approaching axle sensor 15A and confirm the count result of the approaching axle sensor 15A. Hereinafter, the count result of the approaching axle sensor 15A will be referred to as "INc." In this embodiment, the count result of each axle sensor 15 counted by the counting unit 30 is reset to zero in the initial state.

[0044] S30 (approach-side determination 1): The fault determination unit 40 determines whether the approach-side adjacent section ADin is not present on the track and whether the count result INc of the approach-side axle sensor 15A is zero. If it is determined that both conditions are met (YES), it is assumed that the train 50 has not yet entered either the approach-side adjacent section ADin or the detection target section DT, and the process returns to S10 to continue checking the status of the approach-side adjacent section ADin. Figure 4(a) shows the train 50 not yet entering either the approach-side adjacent section ADin or the detection target section DT, and the train 50 is stopped at Station A. On the other hand, if at least one of the conditions in this step S30 is not met (NO), the process proceeds to S40.

[0045] S40 (approach-side determination 2): The fault determination unit 40 determines whether the approach-side adjacent section ADin is not present on the track and whether the count result INc of the approach-side axle sensor 15A is greater than zero. If it is determined that both conditions are met (YES), it is determined that an abnormality has occurred in the track circuit of the approach-side adjacent section ADin, and this information is output to the outside, for example, via a relay (not shown). That is, because the count result INc of the approach-side axle sensor 15A is greater than zero, it is presumed that the approach-side axle sensor 15A has detected the train 50 entering the detection target section DT. Despite this, the presence of the train 50 was not detected in the approach-side adjacent section ADin, so the fault determination unit 40 determines that an abnormality has occurred in the track circuit of the approach-side adjacent section ADin. On the other hand, if at least one of the conditions of this step S40 is not met (NO), the process proceeds to S50.

[0046] S50 (approaching side determination 3): The fault determination unit 40 determines whether the approaching adjacent section ADin is on track and whether the count result INc of the approaching axle sensor 15A is zero. If it is determined that both conditions are met (YES), it is assumed that the train 50 is on track in the approaching adjacent section ADin and has not yet entered the detection target section DT, and the process proceeds to S60. Such a state of the train 50 is shown in Figure 4(b). On the other hand, if at least one of the conditions in this step S50 is not met (NO), the process proceeds to S80.

[0047] S60 (approach-side determination 4): The fault determination unit 40 determines whether the train 50 has changed from being present on the track to being absent on the track in the approach-side adjacent section ADin. As a result, if it is determined that the train 50 has changed from being present on the track to being absent on the track (YES), the process proceeds to S70 because the train 50 is no longer present on the approach-side adjacent section ADin. On the other hand, if it is determined that the train 50 has not changed from being present on the track to being absent on the track and is still present on the approach-side adjacent section ADin (NO), the process returns to S20 above to confirm the train 50's entry from the approach-side adjacent section ADin into the detection target section DT.

[0048] S70 (approach-side determination 5): The failure determination unit 40 determines whether the train 50 is present in the second adjacent section AD2 adjacent to the approach-side adjacent section ADin. As a result, if it is determined that the train 50 is present in the second adjacent section AD2 (YES), it is assumed that the train 50 has returned from the approach-side adjacent section ADin to the second adjacent section AD2, and the process returns to S10 to continue checking the status of the approach-side adjacent section ADin. On the other hand, if it is determined that the train 50 is not present in the second adjacent section AD2 (NO), it is determined that the approach-side axle sensor 15A is faulty, and this determination result is output. That is, if the determination in S60 above determines that the train 50 has changed from being present in the approach-side adjacent section ADin to not being present in the second adjacent section AD2, but the determination in S50 above shows that the count result INc of the approach-side axle sensor 15A by the counting unit 30 does not increase and remains zero, it is determined that the approach-side axle sensor 15A is faulty. Furthermore, since the failure determination unit 40 detects a failure of the approaching axle sensor 15A, the control unit 45 controls the on-track determination unit 35 to determine that a train 50 is on track in the detection target section DT, and outputs this determination result.

[0049] S80 (approach-side determination 6): The failure determination unit 40 determines whether the approach-side adjacent section ADin is present and whether the count result INc of the approach-side axle sensor 15A is greater than zero. As a result, if it is determined that both conditions are met (YES), it is assumed that the train 50 is present in the detection target section DT, and the process proceeds to S90. On the other hand, if at least one of the conditions in this step S80 is not met (NO), taking into account the determination conditions obtained through the above S30, S40, and S50, the count result INc of the approach-side axle sensor 15A is less than zero, regardless of whether the train 50 is present in the approach-side adjacent section ADin. Therefore, the failure determination unit 40 determines that the train 50 is running in the wrong direction or that the approach-side axle sensor 15A is faulty, and outputs this determination result. Furthermore, if the failure determination unit 40 determines that there is a failure in the approaching axle sensor 15A, the control unit 45 controls the on-track determination unit 35 to determine that a train 50 is on track in the detection target section DT, and outputs this determination result.

[0050] S90 (Determination of presence on track in detection target section): The determination in S80 above confirms that the train 50 is present on the track in the approach-side adjacent section ADin, and that as the train 50 enters the detection target section DT, the count result INc of the approach-side axle sensor 15A increases from zero to become greater than the count result of the outgoing-side axle sensor 15B. Therefore, the presence on track determination unit 35 determines that the train 50 is present on the track in the detection target section DT, and outputs this determination result as a signal to control, for example, a relay. Figure 5(a) shows the train 50 present on the track in the detection target section DT.

[0051] S100 (check the state of the outgoing adjacent section): The fault determination unit 40 obtains the track circuit method-based determination result of whether the outgoing adjacent section ADout is occupied or not, and checks the state of the outgoing adjacent section ADout. S110 (Confirm count result of outgoing axle sensor): The on-track determination unit 35 and the fault determination unit 40 obtain the count result of the axles of the train 50 counted by the counting unit 30 at the outgoing axle sensor 15B and confirm the count result of the outgoing axle sensor 15B. Hereinafter, the count result of the outgoing axle sensor 15B will be referred to as "OUTc."

[0052] S120 (leaving-side determination 1): The fault determination unit 40 determines whether the leaving-side adjacent section ADout is not present on the track and whether the count result OUTc of the leaving-side axle sensor 15B remains smaller than the count result INc of the entering-side axle sensor 15A. If it is determined that both conditions are met (YES), it is assumed that the train 50 has not yet reached the leaving-side axle sensor 15B and is still present on the track in the detection target section DT, and the process returns to S100 to continue checking the status of the leaving-side adjacent section ADout. On the other hand, if at least one of the conditions in this step S120 is not met (NO), the process proceeds to S130.

[0053] S130 (leaving-side determination part 2): The fault determination unit 40 determines whether the leaving-side adjacent section ADout is not present on the track and whether the count result OUTc of the leaving-side axle sensor 15B is equal to or greater than the count result INc of the entering-side axle sensor 15A. If it is determined that both conditions are met (YES), it determines that an abnormality has occurred in the track circuit of the leaving-side adjacent section ADout, and outputs this information to the outside, for example, via a relay (not shown). That is, because the count result OUTc of the leaving-side axle sensor 15B is equal to or greater than the count result INc of the entering-side axle sensor 15A, it is estimated that the leaving-side axle sensor 15B has detected the train 50 that has entered the leaving-side adjacent section ADout from the detection target section DT. Despite this, the presence of the train 50 in the leaving-side adjacent section ADout is not detected, so the fault determination unit 40 determines that an abnormality has occurred in the track circuit of the leaving-side adjacent section ADout. On the other hand, if at least one of the conditions in step S130 is not met (NO), the process proceeds to S140.

[0054] S140 (leaving-side determination 3): The failure determination unit 40 determines whether the leaving-side adjacent section ADout is on track and whether the count result OUTc of the leaving-side axle sensor 15B is smaller than the count result INc of the entering-side axle sensor 15A. If it is determined that both conditions are met (YES), the process proceeds to S150 because although the train 50 is on track in the leaving-side adjacent section ADout, the count result OUTc of the leaving-side axle sensor 15B has not reached the count result INc of the entering-side axle sensor 15A. On the other hand, if at least one of the conditions of this step S140 is not met (NO), the process proceeds to S160.

[0055] S150 (Outgoing Side Determination 4): The fault determination unit 40 determines whether the count result OUTc of the outgoing axle sensor 15B is smaller by 1 than the count result INc of the incoming axle sensor 15A and whether the train 50 has transitioned from being present on the track to being absent on the track in the outgoing adjacent section ADout. If it is determined that both conditions are met (YES), it is assumed that an axle has been missed in the outgoing axle sensor 15B due to axle lift. Therefore, the control unit 45 controls the process to proceed to S180. That is, although the count result OUTc of the outgoing axle sensor 15B is smaller by 1 than the count result INc of the incoming axle sensor 15A, it has been confirmed that the train 50 has transitioned from being present on the track to being absent on the track in the outgoing adjacent section ADout. Therefore, it is assumed that the train 50 has transitioned from the detection target section DT to the outgoing adjacent section ADout and has continued onward. This situation is shown in FIG. 6. Therefore, if the difference in the count results is 1, it is assumed that axle lift has occurred.

[0056] On the other hand, if at least one of the conditions in step S150 is not met (NO), this is because the count result OUTc of the outgoing axle sensor 15B is smaller than the count result INc of the incoming axle sensor 15A by two or more, or the train 50 did not change from being present on the track to being absent in the outgoing adjacent section ADout. In the former case, the difference between the count result OUTc of the outgoing axle sensor 15B and the count result INc of the incoming axle sensor 15A is large, making it unlikely that the axle is floating, and a fault is determined to be in the ingoing axle sensor 15A or the outgoing axle sensor 15B. Similarly, in the latter case, since it cannot be confirmed that the train 50 has entered the outgoing adjacent section ADout from the detection target section DT, if there is a difference between the count result OUTc of the outgoing axle sensor 15B and the count result INc of the incoming axle sensor 15A, a fault is determined to be in the ingoing axle sensor 15A or the outgoing axle sensor 15B. Then, since the failure determination unit 40 detects a failure of the approaching axle sensor 15A or the exiting axle sensor 15B, the control unit 45 controls the on-track determination unit 35 to determine that a train 50 is on track in the detection target section DT, and outputs this determination result.

[0057] S160 (Outgoing-side determination 5): The fault determination unit 40 determines whether the outgoing-side adjacent section ADout is on track and whether the count result OUTc of the outgoing-side axle sensor 15B is greater than the count result INc of the incoming-side axle sensor 15A. If it is determined that both conditions are met (YES), the train 50 is on track in the outgoing-side adjacent section ADout, but the count result OUTc of the outgoing-side axle sensor 15B is greater than the count result INc of the incoming-side axle sensor 15A, so the process proceeds to S170. On the other hand, if at least one of the conditions in this step S160 is not met (NO), it is determined that the train 50 is not on track in the detection target section DT, and the process proceeds to S180.

[0058] S170 (Outgoing-side Determination No. 6): The failure determination unit 40 determines whether the count result OUTc of the outgoing-side axle sensor 15B is greater by 1 than the count result INc of the incoming-side axle sensor 15A and whether the train 50 has transitioned from being present on the track to being absent on the track in the outgoing-side adjacent section ADout. If it is determined that both conditions are met (YES), it is presumed that an axle has been missed in the ingoing-side axle sensor 15A due to an axle lift. Therefore, the control unit 45 controls the flow to proceed to S180. That is, although the count result OUTc of the outgoing-side axle sensor 15B is greater by 1 than the count result INc of the incoming-side axle sensor 15A, it has been confirmed that the train 50 has transitioned from being present on the track to being absent on the track in the outgoing-side adjacent section ADout. It is therefore presumed that the train 50 has transitioned from the detection target section DT to the outgoing-side adjacent section ADout and continued onward (see FIG. 6). Therefore, if the difference in the count results is 1, it is presumed that an axle lift has occurred.

[0059] On the other hand, if at least one of the conditions in step S170 is not met (NO), this is because the count result OUTc of the outgoing axle sensor 15B is greater than the count result INc of the incoming axle sensor 15A by two or more, or the train 50 did not change from being present on the track to being absent in the outgoing adjacent section ADout. In the former case, the difference between the count result OUTc of the outgoing axle sensor 15B and the count result INc of the incoming axle sensor 15A is large, making it unlikely that the axle is floating, and a fault is determined to be in the ingoing axle sensor 15A or the outgoing axle sensor 15B. Similarly, in the latter case, since it cannot be confirmed that the train 50 has entered the outgoing adjacent section ADout from the detection target section DT, if there is a difference between the count result OUTc of the outgoing axle sensor 15B and the count result INc of the incoming axle sensor 15A, a fault is determined to be in the ingoing axle sensor 15A or the outgoing axle sensor 15B. Then, since the failure determination unit 40 detects a failure of the approaching axle sensor 15A or the exiting axle sensor 15B, the control unit 45 controls the on-track determination unit 35 to determine that a train 50 is on track in the detection target section DT, and outputs this determination result.

[0060] S180 (Determination of non-existence on track in detection target section): If the process proceeds from S160 to this step S180, taking into account the determination conditions obtained through S120, S130, S140, and S160, it has been confirmed that the outgoing adjacent section ADout is on track and that the count result INc of the incoming axle sensor 15A is equal to the count result OUTc of the outgoing axle sensor 15B. Here, if the same train 50 has passed through both the incoming axle sensor 15A and the outgoing axle sensor 15B, the count results INc and OUTc of the two axle sensors 15A and 15B are equal. Furthermore, the fact that the same train 50 has passed through both the incoming axle sensor 15A and the outgoing axle sensor 15B indicates that the train 50 has entered the detection target section DT but has already entered the outgoing adjacent section ADout. Therefore, the train presence determination unit 35 determines that the train 50 is not present in the detection target section DT, and outputs this determination result.

[0061] Furthermore, under the control of the control unit 45, if the process proceeds from S150 or S170 to step S180, it has been confirmed that the train 50 has departed from the detection target section DT to the exit-side adjacent section ADout based on the judgment conditions of S150 or S170. Therefore, similarly to the above, the train presence judgment unit 35 judges that the train 50 is not present in the detection target section DT and outputs this judgment result. Figure 5(b) shows the train 50 having departed from the detection target section DT and is present in the exit-side adjacent section ADout.

[0062] S190 (Count Result Reset): The control unit 45 resets the count result INc of the incoming axle sensor 15A and the count result OUTc of the outgoing axle sensor 15B, which are calculated by the counting unit 30, to zero. Instead of resetting both count results, the two count results may be compared, and if they are not equal, an adjustment may be made so that the two count results are equal. A case in which the two count results are not equal corresponds to, for example, a case in S150 or S170 above where axle lift is estimated to have occurred and the difference between the count result INc of the incoming axle sensor 15A and the count result OUTc of the outgoing axle sensor 15B is 1. In this case, 1 may be subtracted from the larger count result or added to the smaller count result so that the two count results are equal. After step S190, the process returns to S10 above to check the state of the incoming adjacent section ADin again.

[0063] Here, the axle detection device 10 according to the embodiment of the present invention described above is not limited to the configurations shown in FIGS. 1 to 6 and may have various configurations depending on the situation, application, and the like. For example, the axle sensor 15 may be installed at each end of the detection target section DT, rather than just one at each end. For example, if two axle sensors 15 are installed at each end of the detection target section DT, the control unit 45 may determine the direction of travel of the train 50 from the difference in timing at which the axles are detected by the two axle sensors 15. In other words, if the timing at which one axle sensor 15 detects an axle is earlier than the timing at which the other axle sensor 15 detects an axle, it is considered that the train 50 is traveling from one axle sensor 15 toward the other axle sensor 15. Furthermore, even when one axle sensor 15 is installed at each end of the detection target section DT, the control unit 45 may determine the traveling direction of the train 50 from the timing at which an axle is detected by the axle sensor 15 at each end and the timing at which the presence / absence of the train 50 is detected in the adjacent section AD of the track circuit system that is close to the axle sensor 15. Regardless of the method, the control unit 45 may determine the traveling direction of the train 50 as needed, although this was not specifically mentioned in the explanation of Figures 2 and 3.

[0064] Furthermore, the detection target section DT is not limited to being adjacent to two adjacent sections AD of the track circuit system, but may be adjacent to three or more adjacent sections AD of the track circuit system. For example, Fig. 7 illustrates an example in which the detection target section DT is adjacent to three adjacent sections AD, where the detection target section DT in Fig. 7 is adjacent to one adjacent section AD on the left side of the figure and adjacent to two adjacent sections AD on the right side of the figure where the track branches into two. Even in such a case, at least one axle sensor 15 is installed at each of the three ends of the detection target section DT, and the detection results of two of the axle sensors 15 that are positioned so that each train 50 approaches and exits the detection target section DT as the train 50 progresses are used to determine whether the detection target section DT is on track and to determine whether any of the axle sensors 15 has a fault.

[0065] Furthermore, if the axle detection device 10 cannot use the result of the on-track determination in the second adjacent section AD2 adjacent to the on-track adjacent section ADin, the axle detection device 10 may make the determination without using this result. That is, if it is determined in S60 of Fig. 2 that the train 50 has changed from on-track to off-track in the on-track adjacent section ADin (YES), it may determine that the on-track axle sensor 15A has failed, as described below S70 of Fig. 2, without going through S70 of Fig. 2. Furthermore, although Figs. 1 and 4 to 6 have been described using an example in which the train 50 travels from left to right in the figures, if the train 50 travels in the opposite direction, the on-track side and the on-track side in each figure may be interchanged for interpretation.

[0066] According to the embodiment of the present invention configured as described above, the following advantageous effects can be obtained. Specifically, as shown in Fig. 1, an axle detection device 10 according to the embodiment of the present invention determines whether a train 50 is present on a rail in a detection target section DT that is set between at least two adjacent sections AD where the presence / absence of a train 50 (see Figs. 4 to 6) is determined using a track circuit system, and includes at least two axle sensors 15, a track presence determination unit 35, a fault determination unit 40, and a control unit 45. The at least two axle sensors 15 detect the axles of the train 50 passing through each end of the track in the detection target section DT. When the detection target section DT is between two adjacent sections AD as shown in Fig. 1, at least one axle sensor 15 is installed at one end of the track in the detection target section DT on the adjacent section AD side, and at least one axle sensor 15 is installed at the other end of the track in the detection target section DT on the adjacent section AD side. In contrast, as shown in Figure 7, if one side of the track in the detection section DT is bifurcated and the detection section DT is adjacent to three adjacent sections AD that use the track circuit system to determine whether the train 50 is present on the track, at least one axle sensor 15 is installed at each of the three ends of the track in the detection section DT.

[0067] The track presence determination unit 35 determines whether or not a train 50 is present in the detection target section DT using the detection results of the axle sensors 15. At this time, the track presence determination unit 35 makes the determination using the detection results of two of the at least two axle sensors 15 that are in a positional relationship where the train 50 approaches and leaves the detection target section DT as the train 50 progresses. That is, when the detection target section DT is between two adjacent sections AD as shown in FIG. 1, the axle sensor 15 on one of the adjacent sections AD is the approaching axle sensor 15A, and the axle sensor 15 on the remaining adjacent section AD is the exiting axle sensor 15B, and therefore the detection results of these two axle sensors 15A, 15B are used. 7, even when the detection target section DT is adjacent to three adjacent sections AD, the detection results of two axle sensors 15 that are located at the positions where each train 50 approaches and exits, among the axle sensors 15 installed at each of the three ends of the track in the detection target section DT, are used. The on-track determination unit 35 then determines whether or not a train 50 is on track in the detection target section DT between them, by comparing the detection results of the approaching axle sensor 15A and the outgoing axle sensor 15B, for example.

[0068] The failure determination unit 40 determines a failure in the axle sensor 15 by using the detection results of the axle sensor 15 and the presence / absence determination results of the train 50 in the adjacent section AD of the track circuit system. At this time, the detection results of the two axle sensors 15A, 15B that are in the positional relationship where each train 50 approaches and leaves the detection target section DT as described above are used as the detection results of the axle sensor 15. Furthermore, as the determination results for the adjacent section AD, the presence / absence determination results of the train 50 in two adjacent sections AD close to (adjacent to) the two axle sensors 15A, 15B, i.e., the adjacent section ADin close to the approaching axle sensor 15A and the adjacent section ADout close to the outgoing axle sensor 15B, are used.

[0069] When a discrepancy occurs between the estimated presence / absence of the train 50 in the detection target section DT, which is estimated from the presence / absence determination result of the adjacent section AD, and the axle detection results of the train 50 by each of the two axle sensors 15A, 15B, the failure determination unit 40 determines that one or both of the two axle sensors 15A, 15B are faulty. For example, when the presence / absence determination result of the adjacent section ADin close to the entrance-side axle sensor 15A indicates that the train 50 has entered the detection target section DT, but the entrance-side axle sensor 15A does not detect the axle of the train 50 entering the detection target section DT, the failure determination unit 40 determines that the entrance-side axle sensor 15A is faulty (see S50 and S60 in FIG. 2). This makes it possible to reliably detect a failure on the side where the axle sensor 15 cannot detect the axle.

[0070] The control unit 45 controls the entire axle detection device 10 and controls each component of the axle detection device 10 as needed. As one example of such control, when the failure determination unit 40 determines that one of the axle sensors 15 has failed, the control unit 45 controls the track presence determination unit 35 to determine that the train 50 is present in the detection target section DT. This allows the control unit 45 to safely determine that the train 50 is present in the detection target section DT regardless of whether the axle sensor 15 fails in a way that causes it to continue to detect the axle or in a way that causes it to no longer be able to detect the axle, thereby improving the safety of the axle detection device 10. Furthermore, the failure determination of the axle sensor 15 as described above for performing such control can be achieved by incorporating the results of a train presence determination in the adjacent section AD using a track circuit system, thereby simplifying the device configuration and reducing costs.

[0071] 1, the axle detection device 10 according to the embodiment of the present invention further includes a counting unit 30. The counting unit 30 counts the number of axles of the train 50 passing through each end of the track in the detection target section DT, detected by each of the at least two axle sensors 15. The on-track determination unit 35 compares the count results INc and OUTc by the counting unit 30 of two axle sensors 15A, 15B of the at least two axle sensors 15 that are positioned so that each train 50 approaches and leaves the detection target section DT. If the count result INc of the approaching axle sensor 15A, located on the side from which the train 50 approaches the detection target section DT, is equal to the count result OUTc of the outgoing axle sensor 15B, located on the side from which the train 50 leaves the detection target section DT, the device determines that the train 50 is not present in the detection target section DT (see S140, S160, and S180 in FIG. 3). This determination is based on the fact that even if the count value of the approaching axle sensor 15A increases when the train 50 enters the detection target section DT, if the train 50 has already exited the detection target section DT and the count value of the exiting axle sensor 15B has increased, the count values ​​will always be equal.

[0072] Furthermore, the on-track determination unit 35 determines that the train 50 is present in the detection target section DT when the count result INc of the incoming axle sensor 15A is greater than the count result OUTc of the outgoing axle sensor 15B (see S80 and S90 in FIG. 2). This determination is based on the fact that if the train 50 enters the detection target section DT and the count value of the incoming axle sensor 15A has increased, and if the train 50 is still present in the detection target section DT and the count value of the outgoing axle sensor 15B has not increased, the count value of the incoming axle sensor 15A will be greater than that of the outgoing axle sensor 15B. This makes it possible to more accurately determine whether the train 50 is present on the track in the detection target section DT.

[0073] Furthermore, the axle detection device 10 according to the embodiment of the present invention specifies the conditions for the malfunction determination unit 40 to determine a malfunction of the axle sensor 15 as follows: That is, when the count result INc of the approach-side axle sensor 15A by the counting unit 30 does not increase even though the track circuit system determines that the train 50 has changed from being present on the track to being absent in the approach-side adjacent section ADin close to (adjacent to) the approach-side axle sensor 15A, the malfunction determination unit 40 determines that the approach-side axle sensor 15A has a malfunction (see S50 and S60 in FIG. 2). This is because if the train 50 has changed from being present on the track to being absent in the approach-side adjacent section ADin, it is estimated that the train 50 has entered the detection target section DT from the approach-side adjacent section ADin. However, since the approach-side axle sensor 15A has not detected the axles of the train 50 entering the detection target section DT, the approach-side axle sensor 15A is determined to have a malfunction.

[0074] Furthermore, the fault determination unit 40 determines that the incoming axle sensor 15A or the outgoing axle sensor 15B is faulty when the counting results INc, OUTc of the incoming axle sensor 15A and the outgoing axle sensor 15B by the counting unit 30 are not equal, even though the track circuit system has determined that the train 50 has changed from being present on the track to being absent in the outgoing adjacent section ADout that is close to (adjacent to) the outgoing axle sensor 15B (see S140 to S170 in Figure 3). This is because if the train 50 changes from being present on the track to not being present on the track in the outgoing adjacent section ADout, it is assumed that the train 50 has already left the detection target section DT and entered the outgoing adjacent section ADout (and has also left the outgoing adjacent section ADout), and the count results INc and OUTc of the ingoing axle sensor 15A and the outgoing axle sensor 15B should be equal. However, since these count results INc and OUTc are not equal, it is determined that either the ingoing axle sensor 15A or the outgoing axle sensor 15B has failed. This makes it possible to more accurately detect failures in the ingoing axle sensor 15A and the outgoing axle sensor 15B.

[0075] Furthermore, the axle detection device 10 according to the embodiment of the present invention utilizes not only the result of train presence determination in the adjacent section AD adjacent to the detection target section DT, but also the result of train presence determination in the second adjacent section AD2 of the track circuit system, which is adjacent to the side of the adjacent section AD where the approach-side adjacent section ADin is adjacent to the detection target section DT. That is, if the count result INc of the approach-side axle sensor 15A by the counting unit 30 does not increase even though it is determined that the train 50 has changed from being present on the track to being absent on the track in the approach-side adjacent section ADin, the failure determination unit 40 determines that the approach-side axle sensor 15A is faulty, as described above. However, even in such a case, if the failure determination unit 40 can confirm that the train 50 has returned from the approach-side adjacent section ADin to the second adjacent section AD2 based on the presence / absence determination result of the train 50 in the second adjacent section AD2 adjacent to the approach-side adjacent section ADin, the failure determination unit 40 does not determine that the approach-side axle sensor 15A is faulty (see S70 in FIG. 2).

[0076] This is because when the train 50 changes from being present on the track to being absent on the track in the approach-side adjacent section ADin, it is assumed that the train 50 not only enters the detection target section DT from the approach-side adjacent section ADin but also returns from the approach-side adjacent section ADin to the second adjacent section AD2. Therefore, if this can be confirmed from the determination result of the second adjacent section AD2, the failure determination unit 40 does not determine that the approach-side axle sensor 15A is faulty. In other words, even if it is determined that the train 50 has changed from being present on the track to being absent on the track in the approach-side adjacent section ADin, if the count result INc of the approach-side axle sensor 15A by the counting unit 30 does not increase and it cannot be confirmed from the determination result of the second adjacent section AD2 that the train 50 has returned from the approach-side adjacent section ADin to the second adjacent section AD2, the failure determination unit 40 determines that the approach-side axle sensor 15A is faulty. This makes it possible to avoid erroneous detection of a failure of the approach-side axle sensor 15A and further improve the accuracy of detecting a failure of the axle sensor 15.

[0077] Furthermore, the axle detection device 10 according to the embodiment of the present invention assumes that if a pebble or other foreign object on the rail causes the axle of the train 50 to float above the axle sensor 15, the axle counting will not be successful, and performs the following control to deal with this. The above-described axle floating rarely occurs consecutively, and it is also rare for it to occur simultaneously in the two axle sensors 15A, 15B on the approaching and exiting sides. Therefore, even if axle floating occurs, it is assumed that one count will not be performed by either the approaching axle sensor 15A or the exiting axle sensor 15B.

[0078] Therefore, the control unit 45 checks whether the train 50 has changed from being present on the track to being absent on the track in the detection target section DT based on the track circuit-based determination result of the presence / absence of the train 50 in the outgoing adjacent section ADout that is close to the outgoing axle sensor 15B. As a result, when it is determined that the train 50 has changed from being present on the track to being absent on the track in the detection target section DT, the control unit 45 determines that the axle lift has occurred, rather than that the train 50 is present on the track or that the axle sensor 15 has failed, if the difference between the count result INc of the incoming axle sensor 15A and the count result OUTc of the outgoing axle sensor 15B counted by the counting unit 30 is 1, even if these count results are not equal (see S150 and S170 in FIG. 3).

[0079] The control unit 45 then controls the on-track determination unit 35 to determine that the train 50 is not present in the detection target section DT (see S180 in FIG. 3), and also adjusts the count results of the two axle sensors 15A, 15B by incrementing or decrementing one of the count results by 1 or resetting both count results so that the count results of the two axle sensors 15A, 15B by the counting unit 30 are equal (see S190 in FIG. 3). This makes it possible to avoid the continued determination that the train 50 is present on the track and the erroneous detection of a fault in the axle sensor 15 even if an axle lift occurs, thereby reducing the impact on train operation.

[0080] In addition, the axle detection device 10 according to the embodiment of the present invention determines the traveling direction of the train 50 by using the detection results of at least two axle sensors 15 installed at each end of the track in the detection target section DT and the presence / absence determination results of the train 50 in at least two adjacent sections AD of the track circuit system adjacent to the detection target section DT. That is, when the control unit 45 confirms that the train 50 has changed from being present on the track to being absent on the track in an adjacent section AD and, at approximately the same time, an axle is detected by the axle sensor 15 installed at the end of the adjacent section AD, the control unit 45 determines that the train 50 is traveling from the adjacent section AD toward the detection target section DT. Also, when the control unit 45 detects an axle by the axle sensor 15 installed at the end of the adjacent section AD and, at approximately the same time, confirms that the train 50 has changed from not being present on the track to being present on the track in the adjacent section AD, the control unit 45 determines that the train 50 is traveling from the detection target section DT toward the adjacent section AD. This makes it possible to easily grasp the direction of travel of the train 50, making it possible to more accurately determine whether the train 50 is on the rail or not and to more accurately determine whether the axle sensor 15 has failed. [Explanation of symbols]

[0081] 10: Axle detection device, 15: Axle sensor, 15A: Approaching axle sensor, 15B: Outgoing axle sensor, 30: Counting unit, 35: On-track determination unit, 40: Fault determination unit, 45: Control unit, 50: Train, DT: Detection target section, AD: Adjacent section, ADin: Approaching adjacent section, ADout: Outgoing adjacent section, AD2: Second adjacent section, INc: Count result of approaching axle sensor, OUTc: Count result of outgoing axle sensor

Claims

1. 1. An axle detection device for detecting axles of a train in a detection target section set between at least two adjacent sections for determining whether a train is on the track or not using a track circuit system, the axle detection device detecting axles of a train in a detection target section set between at least two adjacent sections for determining whether a train is on the track or not using a track circuit system, at least two axle sensors for detecting axles of a train passing through each end of the track in the detection target section; a train presence determination unit that determines whether a train is present on the target detection section by using detection results from two of the at least two axle sensors that are in a positional relationship where the train approaches and exits the target detection section according to the progress of the train; a failure determination unit that determines a failure of the two axle sensors by utilizing detection results of the two axle sensors and determination results of whether a train is present on the track or not in two adjacent sections that are close to the two axle sensors among the at least two adjacent sections; a control unit that controls the entire device, The control unit controls the on-track determination unit to determine that a train is present in the detection target section when the failure determination unit determines that any of the axle sensors is faulty.

2. a counting unit that counts the number of axles detected by each of the at least two axle sensors; 2. The axle detection device according to claim 1, wherein the on-track determination unit compares the count results of the two axle sensors counted by the counting unit, and determines that a train is not present in the detection target section if the count result of the approaching axle sensor located on the side where the train enters the detection target section and the count result of the outgoing axle sensor located on the side where the train leaves the detection target section are equal, and determines that a train is present in the detection target section if the count result of the approaching axle sensor is greater than the count result of the outgoing axle sensor.

3. 3. The axle detection device according to claim 2, wherein the failure determination unit determines that the approaching axle sensor is faulty when the count result of the approaching axle sensor by the counting unit does not increase even though it is determined that a train has changed from being present on the track to being absent in an approaching adjacent section of the two adjacent sections that is close to the approaching axle sensor, and determines that the approaching axle sensor or the exiting axle sensor is faulty when the count results of the two axle sensors by the counting unit are not equal even though it is determined that a train has changed from being present on the track to being absent in an exiting adjacent section of the two adjacent sections that is close to the exiting axle sensor.

4. the approach-side adjacent section is adjacent to a second adjacent section that determines whether a train is present on the track using a track circuit system, on the side opposite to the side adjacent to the detection target section; The axle detection device described in claim 3, characterized in that even if the count result of the approach-side axle sensor by the counting unit does not increase even though it is determined that the train has gone from being present on the track to being absent in the approach-side adjacent section, the failure determination unit does not determine that the approach-side axle sensor is faulty if it can be confirmed from the train's presence / absence determination result in the second adjacent section that the train has returned from the approach-side adjacent section to the second adjacent section.

5. 3. The axle detection device according to claim 2, characterized in that, when it is confirmed from the train presence / absence determination result in the outgoing adjacent section, which is closest to the outgoing axle sensor, that the train has changed from being present on the track to being absent on the track in the detection target section, the control unit causes the on-track determination unit to determine that the train is not present on the track in the detection target section even if the difference between the count results of the two axle sensors by the counting unit is 1, and adjusts the count results of the two axle sensors by the counting unit so that they are equal.

6. 2. The axle detection device according to claim 1, wherein the control unit determines the direction of travel of the train by utilizing the detection results of the at least two axle sensors and the determination results of whether the train is present on the track or not in the at least two adjacent sections.

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