Railroad crossings(places where roads and railways intersect at the same level) are places of increased danger for the movement of both types of transport and require special fencing. The priority right of movement at crossings is given to railway transport, and only in the event of an emergency emergency situation special barrier signaling is provided for trains.

In the direction of vehicle movement, crossings are equipped with permanent fencing means - automatic crossing traffic light signaling with automatic barriers; automatic crossing traffic light signaling without barriers; warning crossing alarm, giving notice of the approach of a train; mechanized non-automatic barriers; warning signs and plates.

Automatic traffic light crossing alarm APS provides for the installation of traffic lights with one white and two red lights on both sides on the road (on the right side) 6 m from the crossing. The crossing traffic light gives signals only in the direction of the road. Normally, a white light is on at a crossing traffic light (which indicates that the crossing signaling devices are working properly), and traffic vehicles on relocation is allowed.

Crossing traffic lights, installed on the tracks before crossings, are controlled by the impact on the rail circuits by the moving trains themselves. The prohibitory signal when a train approaches a crossing at the moment the train enters the track circuit is given by the red lights of two lights (heads) of the crossing traffic light, which alternately light up and go out with a frequency of 40 - 45 blinks per minute. Simultaneously with the light signal, a sound signal is given. A signal in the form of alternating red lights is a stop requirement for all types of vehicles.

Automatic barriers complement automatic traffic light crossing signaling at crossings.

Car barriers, when closed, block the entry of vehicles to the crossing, blocking half or the entire carriageway of the road with a barrier bar. The barrier is normally open and when a train approaches, it first gives a prohibiting signal, and then after 7 - 8 seconds (after the traffic lights start giving signals), the barrier beam begins to slowly lower. When the train passes the crossing, the red lights of the crossing traffic lights go out, the white light lights up, and the barrier bar of the automatic barrier rises. There are three lights on the barrier bars of barriers: two red and one white (at the end of the bar).

Automatic warning alarm serves to warn the crossing duty officer about the approach of a train (with a sound and light signal). The person on duty at the crossing himself operates the non-automatic barriers. Typically, warning alarms are used at crossings located within a station or in their immediate vicinity, where it is often impossible to automatically link the operation of the device at the crossing with the movement of trains at the station.

Non-automatic barriers are used in two types: mainly electric, which are opened and closed by an electric motor controlled by the person on duty at the crossing, and mechanical, controlled by levers connected to the barriers by flexible rods.

Currently, the APS is supplemented by railway crossing barrier devices (UZP), which provide automatic fencing of the crossing with barrier devices by lifting their covers when the train approaches the crossing (four covers are installed in the roadbed - two on the right, two on the left); when the covers are lowered there is no interference for vehicles; when a train approaches, at the signal of an automatic crossing alarm, the covers rise and prevent vehicles from entering the crossing, without excluding vehicles from leaving the crossing.

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Crossing signaling devices

Bibliography

1. Classification of crossings and fencing devices

Railway crossings are the intersection of highways and railway tracks at the same level. Movingare consideredobjectsincreaseddangers. The main condition for ensuring traffic safety is: railway transport has an advantage in traffic over all other modes of transport.

Crossings depending on the intensity of railway and road transport, and also depending on the category of roads are divided into fourcategories. Crossings with the highest traffic intensity are assigned category 1. In addition, category 1 includes all crossings in areas with train speeds of more than 140 km/h.

Moving happens adjustable(equipped with crossing signaling devices notifying vehicle drivers about the approach of a train crossing, and/or served by employees on duty) and unregulated. The possibility of safe passage through unregulated crossings is determined by the driver of the vehicle.

The list of crossings serviced by the employee on duty is given in the Instructions for the operation of railway crossings of the Russian Ministry of Railways. Previously, such crossings were briefly called “guarded crossings”; By new instructions and in this work - “moving with an attendant” or “attended moving”.

Crossing alarm systems can be divided into non-automatic, semi-automatic and automatic. In any case, a crossing equipped with a crossing alarm is protected by crossing traffic lights, and a crossing with a man on duty is additionally equipped with automatic, electric, mechanized or manual (horizontally rotating) barriers. Onmovingtraffic lights There are two red lamps located horizontally, which burn alternately when the crossing is closed. Simultaneously with the switching on of crossing traffic lights, acoustic signals are switched on. In accordance with modern requirements, at certain crossings without an attendant, red lights are supplemented white-lunarfire. When the crossing is open, the white-moon light lights up in a flashing mode, indicating the serviceability of the APS devices; when closed, it does not light. When the white-moon lights are extinguished and the red lights are not burning, vehicle drivers must personally ensure that there are no approaching trains.

The following are used on Russian railways: typesmovingalarm:

1 . Traffic lightsignaling. Installed at crossings of access roads and other tracks where approach areas cannot be equipped with rail chains. A prerequisite is the introduction of logical dependencies between crossing traffic lights and shunting or specially installed traffic lights with red and moon-white lights that perform the functions of a barrier.

At crossings with an attendant, the crossing traffic lights are turned on by pressing a button on the crossing signaling panel. After this, the red light at the shunting traffic light goes out and the moon-white light turns on, allowing the movement of the railway rolling unit. Additionally, electric, mechanized or manual barriers are used.

At unmanned crossings, crossing traffic lights are supplemented by a white-lunar flashing light. The closing of the move is carried out by employees of the drafting or locomotive crew using a column installed on the mast of a shunting traffic light or automatically using track sensors.

2 . Automatictraffic lightsignaling.

At unattended crossings located at hauls and stations, crossing traffic lights are controlled automatically under the influence of a passing train. Under certain conditions, for crossings located on a stretch, crossing traffic lights are supplemented with a white-lunar flashing light.

If the approach section includes station traffic lights, then their opening occurs with a time delay after the closing of the crossing, providing the required notification time.

3 . Automatictraffic lightsignalingWithsemi-automaticbarriers. Used at serviced crossings at stations. The closing of the crossing occurs automatically when a train approaches, when setting a route at the station if the corresponding traffic light enters the approaching section, or forcefully when the station duty officer presses the “Closing Crossing” button. The lifting of the barrier bars and the opening of the crossing is carried out by the crossing duty officer.

4 . Automatictraffic lightsignalingWithautomaticbarriers. It is used at serviced crossings on stretches. Crossing traffic lights and barriers are controlled automatically.

In addition, the stations use systems warning alarm. At warningalarm the crossing duty officer receives an optical or acoustic signal about the approach of the train and, in accordance with this, turns it on and off technical means crossing fencing.

2. Calculation of the approach section

To ensure unimpeded passage of the train, the crossing must be closed when the train approaches for a time sufficient for it to be cleared by vehicles. This time is called timenotices and is determined by the formula

t and = ( t 1 +t 2 +t 3), s,

Where t 1 - time required for the car to cross the crossing;

t 2 - equipment response time ( t 2 =2 s);

t 3 - guarantee time reserve ( t 3 =10 s).

Time t 1 is determined by the formula

, With,

Where ? n is the length of the crossing, equal to the distance from the crossing traffic light to a point located 2.5 m from the opposite outer rail;

? p - estimated length of the car ( ? p =24 m);

? O - distance from the place where the car stops to the crossing traffic light ( ? o =5 m);

V p is the estimated speed of the vehicle through the crossing ( V p =2.2 m/s).

The notification time is at least 40 s.

When a crossing is closed, the train must be at a distance from it, which is called calculatedlengthplotapproaching

L p =0.28 V max t cm,

Where V max - the maximum set speed of trains on a given section, but not more than 140 km/h.

The approach of a train to a crossing in the presence of an AB is detected using existing automatic blocking control centers or using track overlay circuits. In the absence of AB, the areas approaching the crossing are equipped with track circuits. In traditional AB systems, the boundaries of the track circuits are located at the traffic lights. Therefore, the notification will be transmitted when the head of the train enters the traffic light. The estimated length of the approach section may be less or greater than the distance from the crossing to the traffic light (Fig. 7.1).

In the first case, the notification is transmitted over one approach section (see Fig. 1, odd direction), in the second - over two (see Fig. 7.1, even direction).

Rice. 1 SitesapproachingTomoving

In both cases, the actual length of the approach section L f is more than calculated L r, because notification of the approach of a train will be transmitted when the head of the train enters the corresponding DC, and not at the moment it enters the calculated point. This must be taken into account when constructing crossing signaling schemes. The use of tonal RCs in AB systems or the use of superposition track circuits ensures equality L f = L p and eliminates this disadvantage.

Significant operational disadvantage of all existing automatic crossing alarm systems (AP) is fixedlengthplotapproaching, calculated based on maximum speed on the section of the fastest train. On a fairly large number of sections, the maximum established speed of passenger trains is 120 and 140 km/h. In real conditions, all trains travel at lower speeds. Therefore, in the vast majority of cases, the crossing is closed prematurely. Excessive time when the crossing is closed can reach 5 minutes. This causes delays for vehicles at the crossing. In addition, drivers of vehicles have doubts about the serviceability of the crossing alarm, and they may start driving when the crossing is closed.

This drawback can be eliminated by introducing devices that measure the actual speed of the train approaching the crossing and generate a command to close the crossing taking into account this speed, as well as the possible acceleration of the train. In this direction, a number of technical solutions. However practical application they didn't find it.

To othersdisadvantage AP systems are an imperfect security procedure atemergencysituationsonmoving ( a stopped car, a collapsed load, etc.). At crossings without an attendant, traffic safety in such a situation depends on the driver. At serviced crossings, the duty officer must turn on the traffic lights. To do this, he needs to turn his attention to the current situation, evaluate it, approach the control panel and press the appropriate button. It is obvious that in both cases there is no efficiency and reliability in detecting an obstacle to the movement of a train and accepting necessary measures. To solve this problem, work is underway to create devices for detecting obstacles at crossings and transmitting information about this to the locomotive. The task of detecting obstacles is implemented using a variety of sensors (optical, ultrasonic, high-frequency, capacitive, inductive, etc.). However, existing developments are not yet technically advanced enough and their implementation is not economically feasible.

3. Block diagram of automatic crossing signaling

Automatic crossing signaling (AP) schemes vary depending on the area of application (span or station), the track development of the section and the accepted organization of train traffic (one-way or two-way), the presence and type of automatic blocking, the type of crossing (serviced or unattended) and a number of other factors. As an example, let's consider the block diagram of an emergency on a double-track section equipped with a cab, with notification in an even direction for two approach sections (Fig. 7.2).

Anyway general scheme AP consists of schemesmanagement, which controls the approach, correct movement of the train and the release of the crossing, and schemesinclusion, which includes moving devices and monitors their condition and serviceability.

The approach of a train is detected using existing AB track circuits. When the train head enters the BU 8P notification transmitter PI transmits information about this through the notification circuit I-OI to the notification receiver At 6th signal installation. With 6SU this information is transmitted to the move.

Upon receipt of a notification, a time delay block BB generates a command to close crossing "Z" after a time that compensates for the difference between the calculated and actual lengths of the approach section. While the train is moving, the crossing remains closed due to the occupancy of DC 6P.

Rice. 2 Structuralschemeautomaticfencingdevicesonmoving

The 6P rail circuit is isolated before the crossing by installing insulating joints. The release of the crossing is recorded by the crossing release control circuit KOP upon the release of this RC. At the same time, the actual passage of the train is checked to avoid false opening of the crossing when applying and removing an extraneous shunt on the RC 6P.

Short-term shunt loss monitoring circuit KPSh generates a command “O” to open the crossing in 10…15 s (to avoid false opening of the crossing in the event of a short-term loss of the shunt while the train is moving along the RC 6P).

Broadcast scheme CxT ensures normal operation of the battery and ALS, transmitting the signal current from the 6Pa rail circuit to the 6P rail circuit.

The crossing is closed by turning on two alternately burning red lights of the crossing traffic lights.

Schemeinclusion With automatic traffic light signaling, it controls crossing traffic light lamps and bells. The serviceability of the red light lamp filaments and their power supply circuits is monitored in cold and hot states. The control circuit for these lights is designed in such a way that the burnout of one lamp, a malfunction of the control circuit or the blinking circuit will not lead to the extinguishment of the crossing traffic light when the crossing is closed.

In an automatic traffic light signaling system with auto barriers ( APS) crossing traffic lights (two red lamps) and a bell are complemented by auto barriers, which are additional means crossing fencing. The electric motors of the barriers are activated 13...15 s after the crossing is closed, which prevents the beam from lowering onto the vehicle. After the beam is lowered, the bell turns off. Operating devices use electric motors DC. Currently, new auto barriers of the PASH1 type are beginning to be introduced. Their advantages are as follows:

· more reliable and economical AC motors are used;

· rectifiers and batteries are not required to power DC motors, which reduces the cost of devices and operating costs;

· lowering of the barrier beam occurs under the influence of its own weight, which increases the safety of train movement in the event of circuit malfunctions or lack of power supply.

In APS systems, when the crossing is cleared by a train, the barrier bars automatically rise to a vertical position, after which the red lights on the traffic lights turn off. With semi-automatic barriers, the lifting of the bars and the subsequent turning off of the red lights occurs when the person on duty at the crossing presses the "Open" button.

In areas with heavy train and vehicle traffic, they are beginning to additionally install devicesbarriersmovingtypeUZP. This device is a metal strip that is located across the road, lies normally in the plane of the road surface and does not interfere with the movement of vehicles. After the barrier beam is lowered, the edge of the lane facing the vehicle rises at a certain angle. This prevents a vehicle that has lost control or is driven by an inattentive driver from entering the crossing. To exclude the possibility of the SPD being triggered under the car or directly in front of it, ultrasonic sensors are used to control the clearness of the SPD location area. For manual control of the UZP and monitoring the condition and serviceability of these devices, a control panel with the necessary control buttons and indication elements is provided.

At crossings equipped with the APS system, it is possible to use barragetraffic lights to transmit information to the driver about an emergency situation at the crossing. The passage or station traffic lights closest to the crossing are used as barrier traffic lights, provided that they are located at a distance of 15...800 m from the crossing and the driver can see the crossing from the place where they are installed. Otherwise, special normally non-lit obstruction traffic lights are installed (see Fig. 2, traffic light Z2). The red light at traffic lights is switched on by the crossing officer when situations arise that threaten the safety of train traffic. In addition to the closing of traffic lights, the supply of ALS code signals to the DC before the crossing stops and the crossing is closed.

To be able to control traffic lights and forced manual control of crossing devices on external wall moving duty booths are being installed shieldmanagement. It has buttons: closing the crossing, opening the crossing, maintaining (keeps the barrier bars from lowering when the crossing is closed), turning on the traffic lights. The same panel provides the following indication:

· approaching trains indicating the direction and route;

· condition and serviceability of crossing and barrier traffic lights. When the traffic lights are turned off, the green lights are on; when the prohibitory indication is turned on, the red indicator lights of the corresponding traffic lights light up. If a traffic light lamp malfunctions, the corresponding green or red indicator light begins to flash;

· state and serviceability of the blinking pattern;

· the presence of main and backup power and the charged state of the batteries (only in new shields of the ShchPS-92 type).

In shields of the ShchPS-75 type, switching incandescent lamps with light filters are used as indicators; in ShchPS-92 shields, AL-307KM (red) and AL-307GM (green) LEDs are used, which are more durable.

4. Features of AP in two-way traffic

With two-way train traffic, the crossing must be automatically closed when a train approaches from any direction, regardless of the direction of action of the AB. This requirement is due to the fact that direction change schemes do not operate stably enough. Therefore, if their operation fails, it is planned to send trains in an unspecified direction by order without using means of automatic control of train movement.

To fulfill this requirement, the following tasks must be solved:

1. Restructuring of AP schemes when changing the direction of train movement.

2. Organization of approach sections and transmission of information about the approach of trains of the established direction for both directions.

3. Organization of control over the approach of a train of an unknown direction.

4. Control of the actual direction of movement of the train in order to block a false command to close the crossing after it has been vacated by a train of the established direction and has entered the approaching section of trains of an unknown direction.

5. Cancel this blocking after a certain time.

6. Exception open state crossing when the utility train returns after it stops at the crossing.

The implementation of these tasks significantly complicated the schemes of traditional AM systems, but ensured the safety of train movement under given conditions.

In accordance with new technical solutions " SchemesmovingalarmFormoving,locatedonhaulsatanymeansalarmAndcommunications (APS-93)" AP schemes have been simplified and unified for use with any type of AB or without AB on both single- and double-track sections. The specified technical solutions provide for the use of existing tonal automatic blocking control centers (see clause 2.4 and section 5), the use of traffic control centers in the form of track circuits superimposed on the track circuits of traditional AB systems, or equipping approach areas with tone control centers in the absence of a battery.

Application tonalRC in AP schemes allowed:

moving house automatic alarm fencing device

1. Implement the system automatic control crossing regardless of the direction of movement of the train and the direction of action of the automatic blocking devices.

2. Ensure the length of the approach section is equal to the design length and eliminate the explosive circuit.

3. Eliminate the need to install insulating joints at the crossing and eliminate the transmission circuit.

4. Eliminate the crossing release control circuit as a separate device.

5. Increase the reliability of monitoring the actual movement of the train.

6. Use the same type of AB schemes for any type of AB or in its absence.

Test questions and assignments

1. What crossings are called regulated?

2. Find the difference in the operation of crossing signaling systems of the “Traffic Light Signaling” and “Automatic Traffic Light Signaling” types.

3. What devices of the APS system protect the crossing? Which ones are basic and which are additional?

4. Think about why the APS system is used only at crossings with a person on duty?

5. What is the disadvantage of systems with a fixed length of the approach section? How can this shortcoming be eliminated?

6. How do crossing devices know when a train is approaching?

7. For what purpose are insulating joints installed at crossings? Is it possible to do without them?

8. List the advantages of barriers of the PASH1 type.

9. Are SPD devices necessary if the crossing is equipped with crossing traffic lights and auto barriers?

Bibliography

1. Kotlyarenko N.F. etc. Track blocking and auto-adjustment. - M.: Transport, 1983.

2. Systems of railway automation and telemechanics / Ed. Yu.A. Kravtsova. - M.: Transport, 1996.

3. Kokurin I.M., Kondratenko L.F. Operational fundamentals of railway automation and telemechanics devices. - M.: Transport, 1989.

4. Sapozhnikov V.V., Kravtsov Yu.A., Sapozhnikov Vl.V. Discrete devices for railway automation, telemechanics and communications. - M.: Transport, 1988.

5. Lisenkov V.M. Theory automatic systems interval regulation. - M.: Transport, 1987.

6. Sapozhnikov V.V., Sapozhnikov Vl.V., Talalaev V.I. and others. Certification and proof of safety of railway automation systems. - M.: Transport, 1997.

7. Arkatov V.S. etc. Rail chains. Operation analysis and maintenance. - M.: Transport, 1990.

8. Kazakov A.A. and others. Interval control systems for train traffic. - M.: transport, 1986.

9. Kazakov A.A. and others. Automatic blocking, locomotive signaling and hitchhiking. - M.: Transport,

10. Bubnov V.D., Dmitriev V.S. Signaling devices, their installation and maintenance: Semi-automatic and automatic blocking. - M.: Transport, 1989.

11. Soroko V.I., Milyukov V.A. Railway automation and telemechanics equipment: Directory: in 2 books. Book 1. - M.: NPF "Planet", 2000.

12. Soroko V.I., Rosenberg E.N. Railway automation and telemechanics equipment: Directory: in 2 books. Book 2. - M.: NPF "Planet", 2000.

13. Dmitriev V.S., Minin V.A. Automatic blocking systems with voice-frequency track circuits. - M.: Transport, 1992.

14. Dmitriev V.S., Minin V.A. Improving automatic blocking systems. - M.: Transport, 1987.

15. Fedorov N.E. Modern systems auto-locking with tone track circuits. - Samara: SamGAPS, 2004.

16. Bryleev A.M. and others. Automatic locomotive signaling and auto-regulation. - M.: Transport, 1981.

17. Leonov A.A. Maintenance of automatic locomotive signaling. - M.: Transport, 1982.

18. Leushin V.B. Fencing devices at railway crossings: Lecture notes. - Samara: SamGAPS, 2004.

19. Automatic blocking with voice-frequency track circuits without insulating joints for double-track sections with all types of traction (ABT-2-91): Guidelines for the design of automation, remote control and communication devices in railway transport I-206-91. - L.: Giprotranssignalsvyaz, 1992.

20. Automatic blocking with voice-frequency track circuits without insulating joints for single-track sections with all types of traction (ABT-1-93): Guidelines for the design of automation, remote control and communication devices in railway transport I-223-93. - L.: Giprotranssignalsvyaz, 1993.

21. Automatic blocking with tone track circuits and centralized equipment placement (ABTC-2000): Standard materials for design 410003-TMP. - St. Petersburg: Giprotranssignalsvyaz, 2000.

22. Crossing signaling schemes for crossings located on stretches with any means of signaling and communication (APS-93): Technical solutions 419311-SCB. TR. - St. Petersburg: Giprotranssignalsvyaz, 1995.

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Operating principle of UZP (Crossing Barrier Device)

The barrier device works as follows: when the drive electric motor is turned on, first the drive lock that held the cover in the lowered position falls off, then, under the influence of the counterweight and the drive gate, the ultrasonic cover is raised at an angle of 30; at the end of the lid lifting phase, the auto switch is triggered and the electric motor is turned off, preparing the power circuit for turning the electric drive back on. Barrier devices, like auto barriers, have dual control - automatic and non-automatic - pressing buttons on the APS panel. In both cases: turning on the signal lights, moving the barrier bars to horizontal (when closing) and vertical (when opening), the ultrasonic covers to the raised (obstructing) - lowered (allowing passage) positions are carried out by de-energizing and, accordingly, energizing the PV relay (in the APS control cabinet ) and its repeaters (in the SPD cabinet). The barrier device works as follows (see Appendix 8). When a train appears in the section approaching the crossing in the relay cabinet of the crossing alarm, the PV relay is de-energized, the PV1 relay is energized, the red flashing lights of the crossing traffic lights are turned on, the UZ cover zone vacancy control system is turned on, and after about 13 s the VM relay is de-energized and the barrier bars begin to lower. From the moment the VM relay is de-energized in the UZP relay cabinet, the VUZ relay (UZ turn-on relay) is turned on, after about 3 s, the BVMSh delay unit is activated, and the relay for lifting the protective UZ, UP and VUZM covers is activated. The friction relay F and the NPS relay are activated, the contacts of which control the ultrasonic drives. The activation of the PPS relay of each of the drives is possible provided that the zones of the ultrasonic covers are free. The control of the free zones of the ultrasonic protection covers is carried out by the front contacts of the safety protection relay, which receives power from the safety protection sensor. RN relays monitor the presence of voltage from the control outputs of the KZK sensors. After the PPS and NPS relays are triggered, power is supplied to the electric motors of the drives; within 4 s, the covers of the UZ occupy a blocking position, preventing vehicles from entering the crossing. The electric motors of the drives are turned off after lifting the ultrasonic covers by the working contacts of the autoswitch. In the case of the electric motors of the drives operating on friction (UZ covers cannot be raised or lowered due to the presence of an obstacle), the NPS relay and electric motors are turned off by the contacts of the friction relay F, which has a drop-off delay of 6 - 8 s. After the PPS and NPS relays are triggered, power is supplied to the electric motors of the drives; within 4 s, the covers of the UZ occupy a blocking position, preventing vehicles from entering the crossing. The electric motors of the drives are turned off after lifting the ultrasonic covers by the working contacts of the autoswitch. In the case of the electric motors of the drives operating on friction (UZ covers cannot be raised or lowered due to the presence of an obstacle), the NPS relay and electric motors are turned off by the contacts of the friction relay F, which has a drop-off delay of 6 - 8 s. The electric motors of the drives are powered from a rectifier device (BP) (VUS-1.3). In case of failure of the main rectifier device BP 1, the contacts of relay A2 switch to the backup rectifier device BP 2 (VUS-1,3). After the train has passed the crossing, the PV relay is excited in the APS relay cabinet and the VUZ relay is turned off in the UZP relay cabinet. The electric motors of the drives begin to work to lower the ultrasonic covers. After the covers are lowered, relays 1PK - 4PK are excited. With the control of the excitation of relays 1PK - 4PK, the relay circuit U1, U2 is closed in the APS relay cabinet, which also controls the raising of the barrier bars, and the red flashing lights of crossing traffic lights are turned off. The person on duty at the crossing also has the opportunity to bring the UZ covers into the blocking position or lower them. In the first case, he needs to press the “closing” button on the APS panel: in the APS cabinet the PV relay is de-energized, the crossing alarm devices are turned on, and in the UZP relay cabinet after 13 s the VUZ relay is triggered and, as in the case automatic feeding notification of the approach of a train, the UZ covers are lifted. To lower the UZ covers, you need to pull out this button. For emergency lowering of the UZ covers, you need to break the seal on the UZ panel with the “normalization” button and press it. The covers of all ultrasonic devices are lowered, and the ultrasonic device is switched off from operation. However, in this case, turning off the flashing red lamps of crossing traffic lights is carried out without controlling the lowering of the UZ covers. Also, a decision was made to eliminate the blinking of the red lamps of crossing traffic lights after pressing the “normalization” button in the event of loss of control of the position of the ultrasonic covers on the contacts of the autoswitches of the ultrasonic drives. The person on duty at the crossing, when pressing the “normalization” button, must make sure that the covers of the control unit are lowered and, if any cover is not in the lower position, finish the operation of the drive using the crank handle. On the UZP panel, to monitor the positions of the covers and the state of the KZK sensors, there are three rows of light bulbs (LEDs) with 4 light bulbs (LEDs) in a row. The top row signals through the control contacts of the drives about the raised, upper position of the covers, the middle row through the front contacts of relays 1PK-4PK - about the lower position of the covers, and the bottom row, with an even burn, signals the serviceable state of the KZK sensors, and by blinking it signals a sensor malfunction. If there is no train in the approaching section, the bottom row of lights (LEDs) does not light up. Three buttons are installed on the UZP panel: - two non-latching, non-sealable buttons, “exit 1” and “exit 3” - for lowering the covers of the first and third UZ, respectively, when vehicles exit the crossing; - a button with a fixation, sealable, “normalization” - for lowering the covers of the ultrasonic device and turning the ultrasonic device off from operation in the event of a malfunction. The control of the non-pressed position of the “normalization” button on the UZP panel is carried out by the lighting of the “normalization” light bulb (LED).

Classification of crossings and fencing devices

Railway crossings are the intersection of highways and railway tracks at the same level. Moving places are considered high-risk objects. The main condition for ensuring traffic safety is the following condition: railway transport has an advantage in traffic over all other modes of transport.

Depending on the intensity of railway and road transport traffic, as well as depending on the category of roads, crossings are divided into four categories. Crossings with the highest traffic intensity are assigned category 1. In addition, category 1 includes all crossings in areas with train speeds of more than 140 km/h.

Moving happens adjustable(equipped with crossing signaling devices notifying vehicle drivers about the approach of a train crossing, and/or served by employees on duty) and unregulated. The possibility of safe passage through unregulated crossings is determined by the driver of the vehicle.

The list of crossings serviced by the employee on duty is given in the Instructions for the operation of railway crossings of the Russian Ministry of Railways. Previously, such crossings were briefly called “guarded crossings”; according to the new Instructions and in this work – “moving with an attendant” or “attended moving”.

Crossing alarm systems can be divided into non-automatic, semi-automatic and automatic. In any case, a crossing equipped with a crossing alarm is protected by crossing traffic lights, and a crossing with a man on duty is additionally equipped with automatic, electric, mechanized or manual (horizontally rotating) barriers. At crossing traffic lights There are two red lamps located horizontally, which burn alternately when the crossing is closed. Simultaneously with the switching on of crossing traffic lights, acoustic signals are switched on. In accordance with modern requirements, at certain crossings without an attendant, red lights are supplemented white-moon fire. When the crossing is open, the white-moon light lights up in a flashing mode, indicating the serviceability of the APS devices; when closed, it does not light. When the white-moon lights are extinguished and the red lights are not burning, vehicle drivers must personally ensure that there are no approaching trains.

The following are used on Russian railways: types of crossing alarms :

1. Traffic light signaling. Installed at crossings of access roads and other tracks where approach areas cannot be equipped with rail chains. A prerequisite is the introduction of logical dependencies between crossing traffic lights and shunting or specially installed traffic lights with red and moon-white lights that perform the functions of a barrier.

At crossings with an attendant, the crossing traffic lights are turned on by pressing a button on the crossing signaling panel. After this, the red light at the shunting traffic light goes out and the moon-white light turns on, allowing the movement of the railway rolling unit. Additionally, electric, mechanized or manual barriers are used.

At unmanned crossings, crossing traffic lights are supplemented by a white-lunar flashing light. The closing of the crossing is carried out by workers of the drafting or locomotive crew using a column installed on the mast of the shunting traffic light or automatically using track sensors.

2. Automatic traffic light signaling.

At unattended crossings located at hauls and stations, crossing traffic lights are controlled automatically under the influence of a passing train. Under certain conditions, for crossings located on a stretch, crossing traffic lights are supplemented with a white-lunar flashing light.

If the approach section includes station traffic lights, then their opening occurs with a time delay after the closing of the crossing, providing the required notification time.

3. Automatic traffic light signaling with semi-automatic barriers. Used at serviced crossings at stations. The closing of the crossing occurs automatically when a train approaches, when setting a route at the station if the corresponding traffic light enters the approaching section, or forcefully when the station duty officer presses the “Closing Crossing” button. The lifting of the barrier bars and the opening of the crossing is carried out by the crossing duty officer.

4. Automatic traffic light signaling with automatic barriers. It is used at serviced crossings on stretches. Crossing traffic lights and barriers are controlled automatically.

In addition, warning alarm systems are used at stations. At warning alarm the crossing duty officer receives an optical or acoustic signal about the approach of a train and, in accordance with this, turns on and off the technical means of fencing the crossing.

Approach Section Calculation

To ensure unimpeded passage of the train, the crossing must be closed when the train approaches for a time sufficient for it to be cleared by vehicles. This time is called notification time and is determined by the formula

t and =( t 1 +t 2 +t 3), s,

Where t 1 – time required for the car to cross the crossing;

t 2 – equipment response time ( t 2 =2 s);

t 3 – guarantee time reserve ( t 3 =10 s).

Time t 1 is determined by the formula

, With,

Where ℓ n – crossing length equal to the distance from the crossing traffic light to a point located 2.5 m from the opposite outer rail;

ℓ р – estimated length of the car ( ℓ p =24 m);

ℓ o – distance from the place where the car stops to the crossing traffic light ( ℓ o =5 m);

V p – the estimated speed of the vehicle through the crossing ( V p =2.2 m/s).

The notification time is at least 40 s.

When a crossing is closed, the train must be at a distance from it, which is called estimated length of the approach section

L p =0.28 V max t cm,

Where V max – the maximum set speed of trains on a given section, but not more than 140 km/h.

In the first case, the notification is transmitted over one approach section (see Fig. 7.1, odd direction), in the second - over two (see Fig. 7.1, even direction).

Rice. 7.1. Areas approaching the crossing

In both cases, the actual length of the approach section L f is more than calculated L p, because notification of the approach of a train will be transmitted when the head of the train enters the corresponding DC, and not at the moment it enters the calculated point. This must be taken into account when constructing crossing signaling schemes. The use of tonal RCs in AB systems or the use of superposition track circuits ensures equality L f = L p and eliminates this disadvantage.

Significant operational disadvantage of all existing automatic crossing alarm systems (AP) is fixed length of approach section, calculated based on the maximum speed on the section of the fastest train. On a fairly large number of sections, the maximum established speed of passenger trains is 120 and 140 km/h. In real conditions, all trains travel at lower speeds. Therefore, in the vast majority of cases, the crossing is closed prematurely. Excessive time when the crossing is closed can reach 5 minutes. This causes delays for vehicles at the crossing. In addition, drivers of vehicles have doubts about the serviceability of the crossing alarm, and they may start driving when the crossing is closed.

This drawback can be eliminated by introducing devices that measure the actual speed of the train approaching the crossing and generate a command to close the crossing taking into account this speed, as well as the possible acceleration of the train. A number of technical solutions have been proposed in this direction. However, they did not find practical application.

Another disadvantage AP systems are an imperfect security procedure in case of an emergency at a crossing(a stopped car, a collapsed load, etc.). At crossings without an attendant, traffic safety in such a situation depends on the driver. At serviced crossings, the duty officer must turn on the traffic lights. To do this, he needs to turn his attention to the current situation, evaluate it, approach the control panel and press the appropriate button. It is obvious that in both cases there is no efficiency and reliability in detecting an obstacle to the movement of a train and taking the necessary measures. To solve this problem, work is underway to create devices for detecting obstacles at crossings and transmitting information about this to the locomotive. The task of detecting obstacles is implemented using a variety of sensors (optical, ultrasonic, high-frequency, capacitive, inductive, etc.). However, existing developments are not yet technically advanced enough and their implementation is not economically feasible.

Moving alarm. General information

Places where railway tracks cross at the same level as roads, tram tracks and trolleybus lines are called railway crossings. For traffic safety, crossings are equipped with fencing devices. On the side of trackless transport, automatic traffic light signaling, automatic barriers and half-barriers, non-automatic barriers with manual mechanical or electric drive together with a warning (automatic or non-automatic) alarm.

With automatic traffic light signaling, the crossing is fenced with special crossing traffic lights, which are installed before the crossing on the side of the road on the right side for the movement of trackless vehicles. Red traffic lights are directed towards the road; they do not light up normally, indicating the absence of trains on the approaches to the crossing, and allow horse-drawn transport to move through the crossing. As the train approaches the crossing, the crossing traffic lights begin to flash alternately, and the bells ring at the same time. From this moment on, the movement of horse-drawn vehicles through the crossing is prohibited. After the train has passed through the crossing, the traffic lights go out, the bells are turned off, and trackless vehicles are allowed to move through the crossing.

With automatic traffic light signaling with automatic barriers, in addition to crossing traffic lights, the movement of vehicles is blocked by a barrier beam. For better visibility, the barrier is painted with red and white stripes and equipped with three lights. Two of them (the middle one and located at the base of the beam) are red, one-sided. They flash red lights towards vehicles. The third lantern, located at the edge of the beam, is double-sided. It lights up red towards vehicles, and white towards the railway track, indicating the border of the blocked part of the road at night.

The barrier or half-barrier beam in the lowered (barrier) position is held at a height of 1-1.25 m from the road surface and blocks vehicles from entering the crossing. When a train approaches a crossing, the barrier bar does not lower immediately after the alarm starts working, but after some time (5-10 s), sufficient for vehicles to pass the barrier, if at the time the alarm was turned on, the vehicle was close to the barrier and the driver could not see red traffic lights. When the barrier beam is in a horizontal position, the lights on the crossing traffic light and beam continue to burn, and the bell turns off. After the train has passed the crossing, the barrier bar rises to a vertical position, the lights on the bar and the traffic light go out, and the movement of trackless vehicles through the crossing is allowed.

Automatic half-barriers, in addition to devices that ensure their automatic operation when trains move, are equipped with non-automatic control devices. The devices are placed on the control panel, the installation location of which is chosen so that the crossing officer on duty at the control panel can clearly see the approach routes of trains and cars.

Buttons for closing and opening the half-barrier are installed on the control panel; button for turning on the barrier alarm (normally sealed); light bulbs that control the appearance of trains at the approaches to the crossing, indicating the direction of train movement; four light bulbs that monitor the serviceability of the traffic light circuits.

If necessary, by pressing the Close the barrier button, the crossing guard can turn on the crossing alarm, which in this case works in the same way as when a train approaches the crossing. After returning (pulling) the button, the half-barrier beam rises to a vertical position and the red lights of the traffic light and the beam go out.

If the automatic control system is damaged, the half barrier remains in the blocking position. If there are no trains on the way, the crossing duty officer can allow vehicles to pass through the crossing. To do this, he presses the Open barrier button. The half-barrier beam rises to a vertical position and the red lights on the traffic light and the beam go out. The button must be kept pressed until the vehicle passes the half-barriers. When the button is released, the half barrier returns to the horizontal position.

At crossings equipped with warning alarms, electric or mechanized barriers, controlled by the crossing duty officer, are used as fencing means. To notify the person on duty at the crossing, automatic or non-automatic light and sound warning alarms are used.

To signal the train to stop in the event of an emergency at a crossing, a barrier alarm is used. Special barrier traffic lights, automatic and semi-automatic blocking traffic lights and station traffic lights are used as barrier signals if they are no more than 800 m from the crossing and the crossing is visible from the place of their installation. Obstacle traffic lights, as a rule, are also mast-mounted; they have a different shape from regular traffic lights. The red lights of the traffic lights do not light up normally. They are turned on by the person on duty at the crossing by pressing the Turn off the traffic lights button on the dashboard. By returning (pulling) the button to its normal position, the traffic lights are turned off. At the same time, the lights on the dashboard light up, monitoring the proper operation of the traffic lights. If the control light does not light up when the barrier signal is turned on, this means that the traffic light is faulty and the crossing officer must take additional measures along the crossing fence from the side of a faulty traffic light.

In areas equipped with automatic blocking, when the barrier alarm is turned on at the automatic blocking signals closest to the crossing, their reading switches to prohibitive and the supply of ALS codes to the track circuits before the crossing stops.

The type of devices used at crossings depends on the category of crossing. On the road network, depending on traffic intensity and visibility conditions, crossings are divided into four categories:

I category-intersections railway with motor roads of categories I and II, streets and roads with tram and trolleybus traffic; with streets and roads along which there is regular bus traffic with a crossing traffic intensity of more than 8 train-buses per hour; with all roads crossing four or more main railway lines;

Category II - intersections with category III roads; streets and roads with bus traffic with a crossing traffic intensity of less than 8 train-buses per hour; city streets that do not have tram, bus or trolleybus traffic; with other roads, if the traffic intensity at the crossing exceeds 50,000 train crews per day or the road crosses three main railway tracks;

Category III - intersections with highways that do not fit the characteristics of crossings of categories I and II, and if the traffic intensity at the crossing with satisfactory visibility exceeds 10,000 train-crews, and with unsatisfactory (bad) - 1,000 train-crews per day. Visibility is considered satisfactory if, from a crew positioned at a distance of 50 m or less from the railway track approaching from any direction, the train is visible at least 400 m away, and the crossing is visible to the driver at a distance of at least 1000 m;

The intensity of traffic at a crossing is measured in terms of train crews, that is, by multiplying the number of trains by the number of crews passing through the crossing per day.

To automatically turn on fencing devices when a train approaches a crossing, approach areas equipped with track chains are arranged. The length of the approach section depends on the notification time, the speed of the train and is determined by the formula

The estimated notification time depends on the length of the crossing, the speed of movement of the crew through the crossing (assumed 5 km/h), the length of the crew (assumed 6 m) and the time of lowering the barrier beam (10 s), if the latter blocks the entire carriageway of the road.

When signaling with electric barriers, the required notification time must be increased by the time the crossing duty officer perceives the notification. In calculations it is taken equal to 10 s. On the Ministry of Railways road network, the minimum acceptable notification time for automatic traffic light signaling without barriers and with half-barriers is 30 s, for automatic barriers that completely block the roadway, 40 s, and for warning signaling - 50 s.

Automatic crossing signaling devices generally use the same equipment and equipment that is used in other railway automation devices. TO special equipment include crossing traffic lights, electric barriers and crossing alarm control panels. Crossing traffic lights without barriers are made with two or three traffic light heads. Adding a third traffic light head allows you to expand the visibility range of signal indications.

Electric barriers of the vertically rotating type are used (Fig. 141). It consists of a barrier beam 1, a cross-shaped signal sign 2 with glass reflectors, two single-digit heads 3, an electric bell 4, a mast 5 attached to the electric drive housing with four bolts, an electric drive 6 and a foundation 7.

The barrier beam of a half-barrier, 4 m long, is completely balanced by weights and is moved from a closed position to an open position and back by an electric motor. During a power outage, the beam must be moved manually. To prevent the beam from breaking when a vehicle hits it, it is fixed in a horizontal position not rigidly, but by two ball latches on the barrier frame and can be rotated about its vertical axis by 45°. When raised, the beam is locked with a transfer mechanism.

The barrier's electric drive consists of a cast iron housing, in which a 95 W DC electric motor with a voltage of 24 V and a rotation speed of 2200 rpm is placed; gearbox with gear ratio 616; drive shaft and auto switch. When working, the gearbox rotates the drive shaft, which controls the barrier bar.

The autoswitch consists of three adjusting cams connected to the drive shaft, which close the contacts at different angles of lift of the barrier beam. A double-arm shock-absorbing device lever is connected to the drive shaft. The drive mechanism is equipped with a friction device that protects the electric motor from overloads.

Submitting your good work to the knowledge base is easy. Use the form below

1. Classification of crossings and fencing devices

Railway crossings are the intersection of highways and railway tracks at the same level. Movingare consideredobjectsincreaseddangers. The main condition for ensuring traffic safety is: railway transport has an advantage in traffic over all other modes of transport.

Moving happens adjustable(equipped with crossing signaling devices notifying vehicle drivers about the approach of a train crossing, and/or served by employees on duty) and unregulated. The possibility of safe passage through unregulated crossings is determined by the driver of the vehicle.

The following are used on Russian railways: typesmovingalarm:

At unmanned crossings, crossing traffic lights are supplemented by a white-lunar flashing light. The closing of the move is carried out by employees of the drafting or locomotive crew using a column installed on the mast of a shunting traffic light or automatically using track sensors.

2 . Automatictraffic lightsignaling.

At unattended crossings located at hauls and stations, crossing traffic lights are controlled automatically under the influence of a passing train. Under certain conditions, for crossings located on a stretch, crossing traffic lights are supplemented with a white-lunar flashing light.

If the approach section includes station traffic lights, then their opening occurs with a time delay after the closing of the crossing, providing the required notification time.

4 . Automatictraffic lightsignalingWithautomaticbarriers. It is used at serviced crossings on stretches. Crossing traffic lights and barriers are controlled automatically.

In addition, the stations use systems warning alarm. At warningalarm the crossing duty officer receives an optical or acoustic signal about the approach of the train and, in accordance with this, turns it on and off technical means crossing fencing.

2. Calculation of the approach section

To ensure unimpeded passage of the train, the crossing must be closed when the train approaches for a time sufficient for it to be cleared by vehicles. This time is called timenotices and is determined by the formula

t and = ( t 1 +t 2 +t 3), s,

Where t 1 - time required for the car to cross the crossing;

t 2 - equipment response time ( t 2 =2 s);

t 3 - guarantee time reserve ( t 3 =10 s).

Time t 1 is determined by the formula

, With,

Where ? n is the length of the crossing, equal to the distance from the crossing traffic light to a point located 2.5 m from the opposite outer rail;

? p - estimated length of the car ( ? p =24 m);

? O - distance from the place where the car stops to the crossing traffic light ( ? o =5 m);

V p is the estimated speed of the vehicle through the crossing ( V p =2.2 m/s).

The notification time is at least 40 s.

When a crossing is closed, the train must be at a distance from it, which is called calculatedlengthplotapproaching

L p =0.28 V max t cm,

Where V max - the maximum set speed of trains on a given section, but not more than 140 km/h.

In the first case, the notification is transmitted over one approach section (see Fig. 1, odd direction), in the second - over two (see Fig. 7.1, even direction).

Rice. 1 SitesapproachingTomoving

3. Block diagram of automatic crossing signaling

Anyway general scheme AP consists of schemesmanagement, which controls the approach, correct movement of the train and the release of the crossing, and schemesinclusion, which includes moving devices and monitors their condition and serviceability.

Upon receipt of a notification, a time delay block BB generates a command to close crossing "Z" after a time that compensates for the difference between the calculated and actual lengths of the approach section. While the train is moving, the crossing remains closed due to the occupancy of DC 6P.

Rice. 2 Structuralschemeautomaticfencingdevicesonmoving

Short-term shunt loss monitoring circuit KPSh generates a command “O” to open the crossing in 10…15 s (to avoid false opening of the crossing in the event of a short-term loss of the shunt while the train is moving along the RC 6P).

Broadcast scheme CxT ensures normal operation of the battery and ALS, transmitting the signal current from the 6Pa rail circuit to the 6P rail circuit.

The crossing is closed by turning on two alternately burning red lights of the crossing traffic lights.

· more reliable and economical AC motors are used;

· rectifiers and batteries are not required to power DC motors, which reduces the cost of devices and operating costs;

· lowering of the barrier beam occurs under the influence of its own weight, which increases the safety of train movement in the event of circuit malfunctions or lack of power supply.

· approaching trains indicating the direction and route;

· state and serviceability of the blinking pattern;

· the presence of main and backup power and the charged state of the batteries (only in new shields of the ShchPS-92 type).

In shields of the ShchPS-75 type, switching incandescent lamps with light filters are used as indicators; in ShchPS-92 shields, AL-307KM (red) and AL-307GM (green) LEDs are used, which are more durable.

4. Features of AP in two-way traffic

To fulfill this requirement, the following tasks must be solved:

1. Restructuring of AP schemes when changing the direction of train movement.

2. Organization of approach sections and transmission of information about the approach of trains of the established direction for both directions.

3. Organization of control over the approach of a train of an unknown direction.

4. Control of the actual direction of movement of the train in order to block a false command to close the crossing after it has been vacated by a train of the established direction and has entered the approaching section of trains of an unknown direction.

5. Cancel this blocking after a certain time.

6. Exception open state crossing when the utility train returns after it stops at the crossing.

The implementation of these tasks significantly complicated the schemes of traditional AM systems, but ensured the safety of train movement under given conditions.

Application tonalRC in AP schemes allowed:

Test questions and assignments

1. What crossings are called regulated?

2. Find the difference in the operation of crossing signaling systems of the “Traffic Light Signaling” and “Automatic Traffic Light Signaling” types.

3. What devices of the APS system protect the crossing? Which ones are basic and which are additional?

4. Think about why the APS system is used only at crossings with a person on duty?

5. What is the disadvantage of systems with a fixed length of the approach section? How can this shortcoming be eliminated?

6. How do crossing devices know when a train is approaching?

7. For what purpose are insulating joints installed at crossings? Is it possible to do without them?

8. List the advantages of barriers of the PASH1 type.

9. Are SPD devices necessary if the crossing is equipped with crossing traffic lights and auto barriers?

Bibliography

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