JPH052546B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" The present invention relates to a train approach warning device used in railway lineside work to detect and warn the progress of a train.

"Background of the Invention" When working along railroad tracks, various inspections and maintenance work are performed after a train has passed and before the next train passes. In this case, as a measure to prevent accidents when trains pass, a method is generally adopted in which a train watchman is placed near the work site and constantly monitors the progress of trains.

When a train lookout visually observes an approaching train, they contact the relevant parties, temporarily halt the construction work, remove obstacles within the construction limits, and ask lineside workers to ensure that the train is passing. The workers will be evacuated until the work is completed to ensure the safety of workers and trains.

However, the reality is that among the causes of accidents related to work along railway lines, many are related to train lookouts. Train watchmen are required to work full-time watching trains. Although the responsibilities of watchmen are heavy, their work is monotonous, and although it is prohibited, they may cause accidents by helping with work, leaving their positions, or not paying attention.

In addition, it is physiologically impossible to maintain a tense state for a long period of time, so in sections where the number of trains is relatively small, when the scheduled time for the train to enter the section approaches, the train must concentrate all its attention on the train. It is common to point in the direction. However, the reality is that there are some issues that cannot be solved with safety education alone, such as not knowing about changes in train schedules, failure to communicate, forgetfulness, and illusions.

"Prior Art" Conventionally, train approach warning devices have been used as an auxiliary means for train watchmen to perform their watchkeeping duties in order to prevent accidents caused by psychological and physiological causes.

Conventional train approach warning systems include: (1) Wayside telephone line (TB) type (uses lineside communication circuits) (2) Track circuit type (uses changes in signal voltage in automatic signal sections) (3) Wired type (The detector installed at a predetermined distance from the work site and the main body of the alarm installed near the work site are connected with an electrical signal cable to predict the passing of a train.) (4) Wireless type (wired type connection) (5) Stationary type (installed in advance in a section with poor visibility and a relatively large number of trains, and turned on before use), etc., depending on the type of work. We select equipment that is compatible with the track structure, track circuit system, etc. of the location where work will be carried out.

Train approach warning systems are mostly used at relatively large-scale construction sites near railway tracks where the construction period lasts several months or more, but they are not used at short-term construction sites or construction sites where the work area is moved daily. Currently, except for the fixed expression (5), it is not used much.

The possible reasons for this are described below for each method.

(1) Wayside telephone line type Since the carrier wave is 18kHz to 22kHz outside the audio frequency range, it cannot be used if a loading coil is inserted within the area where the communication line is used.

Applications must be made to the line administrator in advance, and the service is not open to general construction companies.

The standard installation interval of TB (terminal box) is 500m,
Approximately 200m of cable installation (removal after work) is required.

In areas with heavy snowfall, TBs are installed at high places such as utility poles, making them difficult to use for anyone other than those involved in the communications industry.

(2) Track circuit type This is limited to automatic signal sections, and the usable sections are further limited by the track circuit method. Care must be taken when using in or near station premises or on single-track sections. The method is to issue a warning when a train enters the blocked section, so depending on the work site, it may be necessary to lay several 100 meters of cable.

(3) Wired method This is the most orthodox method, and methods are subdivided depending on the type of train detector, fail-safe method, etc., but because it requires laying cables, it is often avoided for work with a construction period of less than one month. It is.

(4) Wireless type Transmission is carried out over a distance of approximately 400 meters, but depending on the terrain, the range may be insufficient or malfunctions due to other wireless telephones may occur. However, it is not open to general construction contractors.

(5) Fixed type The installation locations, that is, the areas where it can be used are limited.

For these reasons, it is recommended to install alarms and
It has the drawback that removal becomes a heavy burden and is not practical.

In view of the above-mentioned drawbacks of the conventional train approach warning system, the purpose of this invention is to install a detector near the work site, to make it easy to install and remove the detector, and to make it easy to carry all the equipment. The present invention aims to provide a train approach warning device that is smaller and lighter in size and has reliable functionality.

This invention utilizes the fact that the speed of vibration propagating within the rails is much faster than the running speed of the train, and detects rail vibrations caused by trains that are far away from the work point by installing a sensor installed at the work point. The purpose of this project is to provide a device that converts electricity into an electrical quantity using a device, inputs it, and notifies the approach of a train.

There are various causes of sound (vibration) transmitted along the rail, as described below.

(1) Causes due to the train approaching the work site (2) Causes due to the train moving away from the work site (3) Causes due to cars etc. passing through nearby railroad crossings (4) Vibrations caused by the use of a tamper, etc. (5) Due to accompanying construction work (5) Due to trains running on adjacent tracks, etc., but the train proximity warning system must be configured to issue an alarm only when a train (1) approaches the work site. To this end, the inventor analyzed the frequency and amplitude of vibrations propagated to the rail, and their temporal changes. As a result, the following characteristics were found.

When the train (1) approaches, the vibration level increases as the train advances, and the vibration is continuous.

In case (2), the vibration level decreases as the train moves away.

In case (3), the vibration is fragmentary.

In case (4), the vibration level is almost constant.

In case (5), the vibration level is small.

In addition, 1000 to 1100 Hz in the vibration propagating on the rail.
It was also found that vibrations with a frequency of about 1000 nm propagate the farthest distance.

"Means for Solving the Problem" This invention attempts to detect the progress of a train by utilizing the phenomenon (1) that "the vibration level increases as the train advances." be.

To this end, the present invention includes: A a vibration detector that detects rail vibrations that occur when a train is running; B a bandpass filter that filters the signal supplied from the vibration detector; and C a filtered specific frequency. A train approach warning system consists of a processing device that performs a time-series integrated analysis of signals entering the band and determines whether a train is approaching, and a warning device that issues a warning based on the judgment by displaying or issuing a warning. be.

"Operation" According to the configuration of the present invention, the level of vibration gradually increases and the progress of the train is detected by capturing the signals that arrive continuously. In this case, since the present invention detects vibrations propagating through the rails, it is possible to detect the progress of a train relatively far away.

Therefore, the main body of the device housing the vibration detector, the bandpass filter, the time series integration and analysis means, the processing device for determining the progress of the train, etc. can be installed very close to each other.

Therefore, according to the present invention, it is possible to provide a train proximity warning device that is easy to install and remove and is sufficiently durable for practical use.

"Embodiment" FIG. 1 shows an embodiment of the present invention. 10 in the diagram
1 indicates one line of the double track, for example, the down line, and 102 indicates the other line of the double track, for example, the up line. A portion 103 surrounded by a dotted line indicates a work site.

104 and 105 indicate trains approaching this work site 103. Vibration detectors 107 and 108 are installed on the up and down lines 101 and 102 within the range of the work site 103, and are connected to the main body 111 with a cable 109.

FIG. 2 mainly shows the internal structure of the main body 111 in a block diagram. In the figure, 107 and 108 indicate vibration detectors. Vibration detectors 107 and 108 convert vibrations propagating through the rails into electrical signals. This electrical signal is amplified by an amplifier 201 and applied to a bandpass filter 202 .

The bandpass filter 202 is selected to have characteristics that allow signals of 1000 to 1100 Hz to pass through. The reason for this is that it has been confirmed that among the vibrations propagating on the rail, vibrations in this frequency band propagate the farthest.

A signal in a specific band obtained by filtering with a bandpass filter 202 is rectified and smoothed in a rectifier circuit 203, and the rectified and smoothed DC signal is applied to a DC amplifier 204, where it is amplified to a predetermined level. Note that a level control signal is applied to this DC amplifier 204 from a level adjuster 211 to control the gain.

The DC signal amplified by the amplifier 204 is provided to a sample and hold circuit 205, which samples the DC signal at a predetermined period, and provides the sampled sample and hold signal to an AD converter 206 for AD conversion.

The AD-converted digital signal is input to a processing device 207 made up of a microcomputer, and the processing device 207 integrates it in time series to obtain the level change curve A shown in Fig. 3, which determines whether or not a train is moving forward. let

The method for this determination is to set two levels, for example E ₁ and E ₂ , as shown in Figure 3, and check whether level E ₂ is exceeded within a certain time ΔT from the time when level E ₁ is reached. Determine the level within the range of △T
When the train exceeds _E2 , it is determined that a train is approaching, and the alarm device 208 is activated. A level setting means 209 is provided so that the set levels E ₁ and E ₂ can be appropriately selected as E ₀ and E ₁ , E ₁ and E ₂ , and E ₂ and E ₃ depending on the line condition. Depending on this level setting, e.g. E ₀
When E 1 and E ₁ are selected, the distance L from the vibration detectors 107 and 108 that detect the advance of the train is the longest, and when E ₂ and E ₃ are selected, the distance L is the shortest.

For example, in the case of a long rail, the distance L can be increased even if the set voltages E ₂ and E ₃ are selected because the vibration damping is small in the case of a long rail. In other words, the approach of a train can be detected even from a considerable distance. On the other hand, in the case of fixed-length rails, vibrations are damped at the joints. Therefore, in such a case, if the setting levels are set to small values such as E ₀ and E ₁ , it is possible to detect the advance of a train at a sufficient distance for evacuation.

212 indicates a clock oscillator. The clock pulses output from the clock oscillator 212 are applied to a frequency divider 213, which causes the frequency divider 213 to output pulses at time intervals that define, for example, time ΔT, and these pulses are applied to the treatment device 207 to set a lower limit value, e.g. It is used to determine whether or not the level of the input signal exceeds the upper limit setting value, for example, _E1 during the elapse of a predetermined time ΔT from _E0 .

The alarm device 208 may be a visual alarm by lighting a lamp, an acoustic alarm such as a buzzer or a bell, or a combination of both.

214 indicates a liquid crystal display, and this liquid crystal display 2
It is used to display the set values E ₀ to _{E 3} at 14 and to display the arrival of trains.

Reference numeral 215 indicates a fall detector that determines whether the vibration detectors 107, 108 are correctly installed on the rail.

This dropout detector can be constructed, for example, by a push button switch 300 as shown in FIG. In other words, the support 30 is made of an insulator.
1 supports a vibration detector 107 (or 108) consisting of an acceleration sensor. A notch is formed in the side surface of the support body 301, and this notch is engaged with the bottom of the rail. A push button switch 300 is attached to the back of the notch. The operator of the push button switch 300 is made to protrude into the notch, and in this state, the support body 301 is tightened with the fastener 302, and the support body 301 is attached to the rail. At this time, the push button switch 300 is pressed by the rail and operated, The contact signal is input to the processing device 207, and the vibration detectors 107 and 108 are displayed on the display 214.
Displays whether or not it is correctly attached to the rail.

"Effects of the Invention" As explained above, according to the present invention, among the vibrations propagating on the rail, the vibration in the frequency band that propagates farthest is captured, and the vibration is transmitted for a predetermined period of time △T.
Determine whether the increase has exceeded a predetermined level during the period,
If it is detected that the amount has increased to a predetermined level or more during the time ΔT, it is determined that "a train is approaching" and a warning is issued, so that the approach of a distant train can be detected with high accuracy.

As a result, the vibration detector attached to the rail does not have to be extended far away, so it can be easily installed and removed. Therefore, it is convenient to move and use on a daily basis.

[Brief explanation of the drawing]

Fig. 1 is a layout diagram for explaining the overall configuration of this invention, Fig. 2 is a block diagram for explaining an embodiment of the main part of this invention, and Fig. 3 is a diagram showing the operation of the main part of this invention. FIG. 4, which is a graph for explanation, is a sectional view showing an example of a vibration detector used in the present invention. 101,102...Railway, 103...Construction site, 104,105...Train, 107,108...
...Vibration detector, 109...Cable, 111...
Device body, 201...Amplifier, 202...Band filter, 203...Rectifier, 204...DC amplifier, 205...Sample and hold circuit, 206...
...AD converter, 207...processing device, 208...
Alarm device, 212...Clock oscillator, 213...
...Frequency divider, 215...Dropout detector.

Claims (1)

[Scope of Claims] 1A: A vibration detector that detects rail vibrations that occur when a train is running; B: A bandpass filter that filters the signal supplied from this detector; and C: A specific frequency band that is filtered. A train approach warning device comprising: a processing device that performs a time-series integrated analysis of signals entering the area and determines whether a train is approaching;