JP2021017063A - Rail breakage detection device and rail breakage detection method - Google Patents

Abstract

To provide a rail breakage detection device capable of detecting rail breakage from a vehicle side.SOLUTION: A rail breakage detection device detects rail breakage from a vehicle side. The rail breakage detection device includes an acceleration sensor 3 mounted on a vehicle 1, a data recorder 4 for recording acceleration data measured by the acceleration sensor, a high frequency determination unit for performing first determination according to a result obtained by applying high frequency band-pass filter processing to the acceleration data, a low frequency determination unit for performing second determination according to a result obtained by applying low frequency band-pass filter processing to the acceleration data, and a breakage determination unit for determining the presence of a rail breakage portion 21 based on the first and second determination results.SELECTED DRAWING: Figure 1

Description

The present invention relates to a rail breakage detecting device for detecting rail breakage from the vehicle side and a rail breakage detection method.

Rail breakage in railways occurs when the rails are damaged by repeated running of rolling stock, which significantly reduces the running safety of rolling stock. Therefore, as disclosed in Patent Document 1, the railway operator detects the rail breakage by the signal current flowing through the rail for the purpose of detecting the position of the vehicle, which is called a track circuit.

The detection method using a track circuit is a method of detecting when a rail is broken by opening the broken rail and short-circuiting a current. Since the track circuit is a system realized by passing a signal current through the rail, a device that supplies the signal current or power is supplied from the train line to the vehicle, and the rail below it is used for the substation. Maintenance of ground equipment such as impedance bond, which has the role of separating the current different from the signal current of the track circuit such as the current returned to the circuit, requires a great deal of cost.

On the other hand, the development of technology for wirelessly detecting the position of a vehicle is progressing, and the necessity of maintaining a track circuit is decreasing. Then, as disclosed in Patent Documents 2 and 3, a method for detecting rail breakage without using a track circuit is being developed.

For example, in Patent Document 2, an ultrasonic transducer that receives ultrasonic waves propagating on a rail is provided on the ground side, and a railway that outputs an alarm signal when the ultrasonic transducer receives shock vibration generated when a rail breaks. A rail breakage detection device is disclosed. Further, Patent Document 3 also discloses a rail breakage detecting device provided on the ground side.

International Publication No. 2017/175439 Japanese Unexamined Patent Publication No. 2014-80133 Japanese Unexamined Patent Publication No. 2012-91671

However, if a rail breakage detection device is provided on the ground side for a rail having a long extension, even if various measures such as those disclosed in Patent Documents 2 and 3 are made, a large cost is required. The reality is that reduction is difficult.
Therefore, an object of the present invention is to provide a rail fracture detection device capable of detecting rail fracture from the vehicle side and a rail fracture detection method.

In order to achieve the above object, the rail breakage detection device of the present invention is a rail breakage detection device that detects rail breakage from the vehicle side, and is measured by an acceleration sensor attached to the vehicle and the acceleration sensor. A storage unit that records acceleration data, a high-frequency determination unit that makes a first determination from the result of applying high-frequency bandpass filtering to the acceleration data, and a high-frequency bandpass filtering unit that makes a first determination from the result of applying low-frequency bandpass filtering to the acceleration data. It is characterized in that it includes a low frequency determination unit that makes the determination of 2 and a break determination unit that determines the presence or absence of rail breakage based on the first and second determination results.

Here, the acceleration sensor can be attached to the axle box support device or the bogie of the vehicle to measure the vertical acceleration. Further, the high frequency bandpass filter processing is preferably a filter in a frequency band of 300 Hz to 800 Hz. Further, the low frequency bandpass filter processing is preferably a filter in the frequency band of 0.001 Hz to 30 Hz. Further, the acceleration data may be configured to be recorded in the storage unit together with the data related to the position information.

The invention of the rail breakage detection method is a rail breakage detection method for detecting rail breakage from the vehicle side, and includes a step of acquiring acceleration data by running a vehicle equipped with an acceleration sensor along the rail. The first determination is made from the result of applying the high frequency bandpass filter processing to the acceleration data, and the second determination is made from the result of applying the low frequency bandpass filter processing to the acceleration data. It is characterized by including a step of determining the presence or absence of rail breakage based on the first and second determination results.

The rail breakage detection device of the present invention configured in this way utilizes the acceleration data measured by the acceleration sensor attached to the vehicle, and makes two determinations by the high frequency determination unit and the low frequency determination unit. Then, the presence or absence of rail breakage is determined based on these first and second determination results.

With such a configuration, rail breakage can be detected from the vehicle side without providing any equipment on the ground side. Further, the acceleration sensor can be attached to a vehicle axle box support device, a bogie, or the like, and an acceleration sensor pre-attached to these positions can also be used. Further, if the acceleration data is recorded in the storage unit together with the data related to the position information, it becomes possible to identify the rail breakage point after the vehicle travels and take prompt measures such as repair.

Further, in the invention of the rail breakage detection method, a vehicle equipped with an acceleration sensor is traveled along the rail to acquire acceleration data, and the measured acceleration data is subjected to high-frequency bandpass filter processing and low-frequency bandpass filter processing. The presence or absence of rail breakage is determined by using the result of the application. That is, the rail breakage can be detected from the vehicle side without providing any equipment on the ground side.

It is explanatory drawing which showed typically the structure of the rail breakage detection apparatus of this embodiment. It is a figure for demonstrating the acceleration waveform when running a rail without abnormality, (a) is an explanatory view which showed the state of a rail and the structure of the carriage of the vehicle traveling on it, (b) is an acceleration sensor. It is a figure exemplifying the acceleration data measured by. It is a figure for demonstrating the acceleration waveform at the time of rail rupture, (a) is an explanatory view which showed the state which sinking occurs by rail rupture, and (b) is acceleration data measured by an acceleration sensor. It is a figure exemplifying. It is explanatory drawing which compared and showed the time history waveform of the wheel load when the opening width of a rail fracture was changed. It is a flowchart explaining the process flow of the rail breakage detection method of this embodiment. It is explanatory drawing for demonstrating the 1st determination while displaying together the acceleration data and the result of having performed the high frequency bandpass filter processing. It is explanatory drawing for demonstrating the 2nd determination while displaying the acceleration data and the result of having performed low frequency bandpass filter processing together.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory diagram schematically showing a configuration of a rail fracture detection device according to the present embodiment.

The rail 2 constituting the track may break due to repeated contact with the wheels 12 of the vehicle 1 traveling along the rail 2. When an opening is generated as the rail breaking point 21, it may become a sinking point 211 as shown in FIG. 3A depending on the state. In short, the rail 2 is delivered onto the sleepers 22 and fixed by the fastening device 23, but when the rail breaks between the sleepers 2 and 2, the cantilever-shaped rail 2 sinks. It may be 211.

On the other hand, the vehicle 1 may be a maintenance vehicle or a general railroad vehicle constituting a train or the like. In the following, a vehicle 1 in which the bogies 11 are arranged at intervals in the front-rear direction on a rectangular parallelepiped box-shaped vehicle body will be described as an example.

The bogie 11 includes a bogie frame 111 having a rectangular shape in a plan view, and wheels 12 traveling on each of the pair of rails 2 are connected by an axle. Further, one bogie 11 is provided with a combination of two sets of wheels 12 and an axle (wheel axle) in the front-rear direction. Further, an axle box 112 and an axle box support device are provided at the end of the axle.

The acceleration sensor 3 is attached to at least one place such as the bogie frame 111 and the axle box support device of the bogie 11 configured in this way. The acceleration sensor 3 is attached so that the acceleration in the vertical direction (vertical acceleration) can be measured.

The acceleration sensor 3 is connected to the data recorder 4 mounted on the vehicle 1 by wire or wirelessly. The data recorder 4 serves as a storage unit for recording acceleration data measured by the acceleration sensor 3.

Then, the acceleration data recorded in the data recorder 4 is analyzed by a PC unit 5 such as a personal computer provided with an arithmetic processing unit. The PC unit 5 may be mounted on the vehicle 1 or may be installed in a management building or the like different from the vehicle 1. Further, when the PC unit 5 is located in a place other than the vehicle 1, the data may be transferred from the data recorder 4 in real time or periodically, or the data recorder 4 or the flash memory inserted therein may be stored. The configuration may be such that data is transferred when a medium is connected.

The PC unit 5 has a high-frequency determination unit that makes a first determination, a low-frequency determination unit that makes a second determination, and a fracture that determines the presence or absence of rail fracture based on the first determination result and the second determination result. A determination unit is provided as a determination processing unit.

The high frequency determination unit makes the first determination based on the result of applying the high frequency bandpass filter processing to the acceleration data. The high-frequency bandpass filter is a filter for extracting a response (acceleration) generated shockingly when the wheel 12 comes into contact with the rail 2.

This response is due to the wheel 12 and the rail contact spring, and has a frequency of 2000 Hz or less. Moreover, in the measurement results so far, such a response is observed even at about 100 Hz or higher. Therefore, as a high-frequency bandpass filter, a filter in the frequency range of 100Hz-2000Hz can be used. On the other hand, in order to distinguish it from the response generated from the irregularity of the orbit such as floating pillow and wavy wear, it is better to set it to about 300 Hz or higher. For this reason, it is preferable to use a frequency band in the range of 300 Hz to 800 Hz.

The low frequency determination unit makes a second determination based on the result of applying the low frequency bandpass filter processing to the acceleration data. The low frequency bandpass filter is a filter for extracting the response (acceleration) generated by the mass of the wheel set and the shaft spring and the raceway spring. As a low frequency bandpass filter, a filter in the frequency band of 0.001Hz-30Hz can be used.

Here, FIG. 2 is a diagram for explaining an acceleration waveform when the vehicle 1 is driven along a rail (healthy portion) having no abnormality. FIG. 2A shows a state of the rail of the sound portion and a state in which the acceleration sensor 3 is attached to the bogie 11 of the vehicle 1 traveling on the rail.

Then, FIG. 2B is a diagram illustrating the acceleration data measured by the acceleration sensor 3 of the vehicle 1 traveling on the sound portion of the rail 2. This figure shows the acceleration waveform RD created by the acceleration data and the amplitude center RD1.

On the railroad track, there are floats of seams and sleepers 22 and defective parts of the fastening device 23. When the vehicle 1 travels in such a location, a response different from that of the sound portion is shown as the vertical acceleration of the axle box support device and the bogie frame 111.

FIG. 3 is a diagram for explaining an acceleration waveform when a rail break occurs. FIG. 3A shows a state in which the sinking portion 211 is generated due to the rail breakage. Further, FIG. 3B is a diagram illustrating acceleration data measured by the acceleration sensor 3 of the vehicle 1 traveling in the subduction point 211.

In addition to the above-mentioned seams and sleepers 22 floating, when the vehicle 1 travels on the rail breakage point or sinking point 211, a response different from that of the sound part is the vertical acceleration of the axle box support device and the bogie frame 111. Will be shown. In order to detect rail rupture, it is necessary to distinguish the response of the rail rupture portion from these various responses.

FIG. 4 shows the time history waveform of the wheel load when the vehicle 1 is driven by changing the opening width of the rail fractured portion to 70 mm, 100 mm, and 150 mm. Here, the wheel load refers to a force by which the wheel 12 pushes the rail 2 downward.

It is said that the wheel load and the vertical acceleration of the axle box support device are closely related. Looking at the waveform of this wheel load, it can be seen that the characteristic high-frequency region HF and low-frequency region LF are generated in each case of the opening width.

The waveform of the high frequency region HF is a response generated shockingly when the wheel 12 comes into contact with the rail 2 when the vehicle 1 travels on the rail fractured portion. This waveform appears not only at the rail breakage portion but also when traveling at a seam or the like.

The waveform of the low frequency region LF means a waveform that fluctuates for several seconds after the wavelength of the high frequency region HF. In the sound part, the rail 2 is continuously supported by the sleepers 22 like a continuous beam, whereas in the rail break part, the rail 2 becomes discontinuous so that the rail 2 looks like a cantilever. It will be supported. As a result, it is considered that such a response is obtained because the displacement of the wheel set in the vertical direction becomes large when the rail fractured portion travels and the track is in a different support mode.

Wheelset springs, mass and orbital springs are involved in such behavior. Then, it is assumed that the response in this frequency band appears as a near mode even when the sleeper 22 is floating in the orbit or the fastening device 23 is defective.

Therefore, in order to set the frequency band of the low-frequency bandpass filter processing, the analysis is performed based on the vehicle 1 traveling on the line section for inspecting the rail breakage and the track. Here, in modeling the wheel set and the track, there is a method of approximating the track to an elastic floor beam of infinite length in order to easily grasp the deflection of the track. For example, details are described in "Hiroshi Sato," Effects on Construction Vibration of Orbital Structure ", JSCE Proceedings, No. 240, pp.63-70, 1975".

With this modeling technique, the trajectory can be simply replaced with one mass point and one spring. If the track is replaced by a mass point and a spring, a vibration model consisting of the spring of the track, the mass of the track, the contact spring of the wheel and the rail, the wheel and the shaft spring can be considered.

Then, by calculating the eigenvalues of this vibration model, the natural frequencies of the coupled vibrations of the track, the wheels, and the vehicle body can be easily calculated. Therefore, various parameters required for the calculation were set, and the coupled vibration when it was considered that there was an opening in the orbit was calculated. The parameters to be set are sleeper spacing, rail mass per unit length, sleeper mass, track pad spring constant, spring constant under the sleeper, rail longitudinal Young's modulus, cross section quadratic around the horizontal axis of the rail. The moment, the mass of the wheel, the contact spring between the wheel and the rail, the mass corresponding to the load on the wheel, the spring constant of the shaft spring, and the like.

The natural frequencies calculated by such analysis were such that the primary natural frequency was about 2 Hz, the secondary natural frequency was about 26 Hz, and the tertiary natural frequency was about 1000 Hz. For example, considering the second-order vibration mode, the natural frequency was a little less than 30 Hz when the orbits were discontinuous, but compared to the case where the orbits were continuous, the effective length of the mass contributing to the vibration and the spring It is probable that the natural frequency of the secondary mode decreased due to the change in the effective length. That is, it can be seen that the support rigidity of the wheel changes locally depending on the opening, and the vibration due to the unique resonance frequency of less than 30 Hz is excited at the opening. Therefore, the low frequency bandpass filter was set to the frequency band of 0.001Hz-30Hz as described above.

Next, the rail breakage detection method of the present embodiment will be described with reference to the flowchart shown in FIG.

First, as described above, the acceleration sensor 3 is attached to the side surface of the bogie frame 111 of the bogie 11 of the vehicle 1 and the axle box support device around the axle box 112. The acceleration sensor 3 may be attached to at least one place so that the vertical acceleration can be measured. The acceleration sensor 3 is connected to the data recorder 4 mounted on the vehicle 1.

In step S1, by running the vehicle 1 along the rail 2, acceleration data such as the axle box acceleration which is the vertical acceleration of the axle box support device and the bogie acceleration which is the vertical acceleration of the bogie 11 (bogie frame 111) are detected. Let me.

The acceleration data detected by the acceleration sensor 3 is recorded in the data recorder 4 together with information that can be converted into position information such as a distance (step S2). For example, when the vehicle 1 is driven at a constant speed, it can be converted into position information by associating the measurement time with the acceleration data. In addition, position information based on GPS (Global Positioning System) can be linked to the measured acceleration data.

The acceleration data recorded in the data recorder 4 is transferred to the PC unit 5 which is the determination processing unit (step S3). In the determination processing unit, the high frequency determination unit performs the processing of steps S41, S411, S421, and S413, and the low frequency determination unit performs the processing of steps S42, S421, S422, and S423.

In the following, in order to make the explanation of the determination processing unit easy to understand, the description will be given with reference to the application examples shown in FIGS. The application examples shown in these figures are the results when the opening P1 simulating the rail fractured portion is run at a train speed of 30 km / h. Here, seams P2 and P2 were simulated before and after the opening P1.

FIGS. 6 and 7 show acceleration data (acceleration waveform RD) of vertical acceleration measured by the acceleration sensor 3 of the axle box support device, with the horizontal axis representing the measurement time and the vertical axis representing the amplitude (unit: G). .. Then, FIG. 6 also displays the result of high-frequency bandpass filter processing (high-frequency processed waveform HD), and FIG. 7 also shows the result of low-frequency bandpass filter processing (low-frequency processed waveform LD). Was displayed.

That is, in step S41, when the acceleration waveform RD is subjected to high frequency bandpass filter processing in the frequency band of 300 Hz to 800 Hz, the high frequency processed waveform HD of FIG. 6 is generated. Therefore, a comparison is performed with a preset threshold value (for example, 1.0 G) (step S411).

As a result of comparison with the threshold value (1.0 G), if there is no portion exceeding the threshold value in the high frequency processing waveform HD, the first determination result of "no abnormality" is obtained (step S412). On the other hand, the portion where the high-frequency processing waveform HD exceeds the threshold value (1.0 G) is the first determination result that it is either the opening P1 (rail break portion) or the seam P2 (step S413).

On the other hand, in step S42, when the acceleration waveform RD is subjected to low frequency bandpass filter processing in the frequency band of 0.001 Hz to 30 Hz, the low frequency processed waveform LD of FIG. 7 is generated. Therefore, a comparison is performed with a preset threshold value (for example, 1.5 G) (step S421).

As a result of comparison with the threshold value (1.5G), if there is no portion exceeding the threshold value in the low frequency processing waveform LD, the second determination result of "no abnormality" is obtained (step S422). On the other hand, the second determination that the portion where the low-frequency processing waveform LD exceeds the threshold value (1.5G) is either the opening P1 (rail breaking portion), the defect of the fastening device 23, or the floating sleeper 22. The result is (step S423). That is, at the joint P2, the low frequency processing waveform LD does not exceed the threshold value (1.5G).

In step S5, the first determination result and the second determination result are output to a monitor or the like connected to the PC unit 5. Subsequently, the fracture determination unit of the determination processing unit determines whether or not both the first determination result and the second determination result exceed the threshold value (step S6). That is, it is confirmed whether or not both steps S413 and S423 have been passed.

As a result, if the first determination result is based on step S413 and the second determination result is based on step S423, it is determined that "there is a rail break" (step S7). On the other hand, if the first determination result is due to step S412 or the second determination result is due to step S422, it is determined that there is no rail breakage (step S8).

When there is no rail breakage, there are "when there is no abnormality" and "when there is a defect in the fastening device 23". That is, the case where both the first judgment result and the second judgment result are "no abnormality" (step S421, step S422) is "the case where there is no abnormality", and the first judgment result is based on step S412 and the second judgment is made. When the result is according to step S423, it becomes "when there is a defect of the fastening device 23 or a floating sleeper 22". Further, when the first determination result is based on step S413 and the second determination result is based on step S422, it is "when there is a seam P2".

Next, the operation of the rail breakage detection device and the rail breakage detection method of the present embodiment will be described.
The rail breakage detection device of the present embodiment configured in this way uses the acceleration data measured by the acceleration sensor 3 attached to the vehicle 1 and makes two determinations by the high frequency determination unit and the low frequency determination unit. I do. Then, the presence or absence of rail breakage is determined based on these first and second determination results.

With such a configuration, rail breakage can be detected from the vehicle 1 side without providing any equipment on the ground side. Further, the acceleration sensor 3 can be attached to the axle box support device of the vehicle 1, the carriage 11, or the like, and if there is an acceleration sensor 3 attached in advance for a purpose other than rail breakage detection at these positions, it is used. You can also do it.

Further, if the acceleration data is recorded in the data recorder 4 together with the data related to the position information, even if the acceleration data recorded in the data recorder 4 is verified after the vehicle travels and the rail breakage is detected, the track is tracked by the distance or the like. The position of the can be specified, and repairs and other measures can be taken promptly.

Further, in the invention of the rail breakage detection method, a vehicle 1 equipped with an acceleration sensor 3 is traveled along the rail 2 to acquire acceleration data, and the measured acceleration data is subjected to high-frequency bandpass filtering and low-frequency bandpass. The presence or absence of rail breakage is determined by using the result of filtering. That is, the rail breakage can be detected from the vehicle side without providing any equipment on the ground side.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes to the extent that the gist of the present invention is not deviated are described in the present invention. Included in the invention.

For example, in the above embodiment, the case where the acceleration sensor 3 is attached to both the axle box support device and the bogie frame 111 has been described, but the present invention is not limited to this, and any one of them may be used from three or more locations. The obtained measurement result may be statistically processed and used. Further, the acceleration data may be measured by attaching it to a position different from the illustrated location.

1: Vehicle 11: Bogie 2: Rail 21: Rail break point 3: Accelerometer 4: Data recorder (storage unit)
HD: High frequency processing waveform LD: Low frequency processing waveform

Claims (6)

It is a rail breakage detection device that detects rail breakage from the vehicle side.
Accelerometer attached to the vehicle and
A storage unit that records acceleration data measured by the acceleration sensor,
A high-frequency determination unit that makes a first determination based on the result of applying high-frequency bandpass filter processing to the acceleration data, and
A low-frequency determination unit that makes a second determination based on the result of applying low-frequency bandpass filter processing to the acceleration data, and
A rail rupture detecting device including a rupture determination unit for determining the presence or absence of rail rupture based on the first and second determination results. The rail breakage detecting device according to claim 1, wherein the acceleration sensor is attached to an axle box support device or a bogie of the vehicle to measure vertical acceleration. The rail breakage detecting device according to claim 1 or 2, wherein the high-frequency bandpass filter processing is a filter in a frequency band of 300 Hz to 800 Hz. The rail breakage detection device according to any one of claims 1 to 3, wherein the low-frequency bandpass filter processing is a filter in a frequency band of 0.001 Hz to 30 Hz. The rail breakage detecting device according to any one of claims 1 to 4, wherein the acceleration data is recorded in the storage unit together with data related to position information. It is a rail breakage detection method that detects rail breakage from the vehicle side.
The step of acquiring acceleration data by running a vehicle equipped with an acceleration sensor along the rail,
The step of performing the first determination from the result of applying the high frequency bandpass filter processing to the acceleration data, and
The step of performing the second determination from the result of applying the low frequency bandpass filter processing to the acceleration data, and
A method for detecting rail breakage, which comprises a step of determining the presence or absence of rail breakage based on the first and second determination results.