Automatic crossing alarm devices. Operating principle of the UZP (Crossing Barrier Device) When closing the crossing, the train must be located at a distance from it, which is called the estimated length of the approach section

30.11.2017

A railway crossing is a place where the railway track intersects at one level with automobile, tram, trolleybus and horse-drawn roads. That is, this is a high-risk area in which railway transport has priority.

A railway crossing alarm is, first of all, a means of notifying non-core traffic participants about the approach of a train.

Now all new crossings are equipped with automatic crossing alarms (APS). Existing unregulated railway crossings are also equipped with APS systems both within and within the framework, one of the stages of which is.

And here we can already say that automatic railway crossing signaling is not only a means of notification and warning. In some cases, this is also a system for preventing unauthorized entry onto railway tracks. , with the strong desire of the car owner (and sometimes without his desire - if the brakes fail, for example) - will not interfere with driving onto the railway track.

Do you need to install an alarm at crossings? Installation of APS and installation of the APS system are specialists. !

What is APS

Automatic signaling of railway crossings is a set of signaling devices, depending on operating conditions, representing:

Automatic: At each end of the crossing with two or three traffic light heads and an electric bell.
Automatic traffic light alarm +: in addition to this, barrier bars for barriers are installed.
Automatic warning alarm with manually controlled barriers that close at the touch of a button.

Installation of APS is possible both at guarded (with a crossing post) and at unguarded (without a post) crossings.

The APS is used in conjunction with devices, allowing them to transmit all available information about the status of moving equipment to the nearest station. The standard automatic signaling is turned on/off using a cut rail circuit (RC) with a cut point at the railway crossing.

Installation of the APS system is carried out using placed in.

What should an automatic crossing alarm provide?

A railway crossing alarm system must ensure timely and correct operation of all devices included in the system of a specific alarm system. Not only the duration of downtime of non-core modes of transport before a closed crossing depends on this, but also the safety of train and any other type of traffic at the crossing.

Places where railroads and roads intersect at the same level are called railroad crossings. Crossings serve to improve traffic safety and are equipped with fencing devices.

Depending on the intensity of train traffic at crossings, fencing devices are used in the form of automatic traffic light signaling, automatic crossing signaling with automatic barriers. Railway crossings can be equipped with automatic traffic light signaling devices; they can be guarded (serviced by an employee on duty) or unguarded (not serviced by an employee on duty). In this course project, the crossing is guarded, with automatic barriers with a beam length of 6 meters. Crossing traffic lights are used type II-69. An electric bell of the ZPT-24 type is placed on the mast of the crossing traffic light. These traffic lights use LED heads with a supply voltage of 11.5 V.

The control circuit for crossing signaling on a single-track section with numerical code automatic blocking includes the following relays: 1I. 2I pulse track relays are used to fix the vacancy-occupancy of a block area, I - general repeater of pulse track relays, DP - additional track relay, DI additional pulse, IP proximity detector (see sheet 9.1), IP1, 1IP, PIP proximity detector repeaters , N - direction relay, 1N, 2N - direction relay repeaters, B - switching relay, KT - control thermal relay, 1T, 2T - transmitter relays, 1PT, 2PT - direction relay repeaters, K - control relay, F, Z - signal relay, Zh1 - relay repeater Zh, 1S - counter relay, B - blocking relay, NIP - proximity detector in unknown direction of movement, B1Zh, B1Z - blocking relays.

The state of the circuit corresponds to a given odd direction of movement, a free approach section, and an open crossing.

Within the block section on which the crossing is located, two track circuits 3P, 3Pa are equipped, in which, for a given odd direction of movement, the supply end is 1P, and the relay end is 2P, relay I is a pulse track type IVG - reed switch. When the block section is free, the 3Pa rail circuit from traffic light 4 through contact 1T is encoded with a code, the meaning of which is determined by the signal reading of traffic light 1. At the crossing, relay 2 I, as well as its repeaters 1T, I, operate in the incoming code mode. Through the contact of a common pulse repeater relay (relay I), the BS-DA decoder is turned on, the output circuits of which activate the signal relays, Ж, З, Ж1, depending on the readings of the traffic light ahead. Through the front contacts of relay Zh, Zh1, and the normal contact of relay N, relay 1PT (direction relay repeater) is activated. Relay 1T, operating in pulse mode, switches its contact in the relay circuit 1TI, which in turn transmits codes to the track circuit 3P.

When a train enters the Ch1U departure section, the crossing alarm is activated in two approach sections. From this moment on, the IP notification relay at traffic light 3 is de-energized. By releasing the armature, this relay changes the polarity of the current from forward to reverse in the IP relay circuit at the crossing. Excited by a current of reverse polarity, this relay switches the polarized armature, de-energizing the 1IP relay at the crossing. After de-energizing, relay 1IP turns off relay IP1. IP1 turns off relay B, the crossing is closed. When the train enters section 3P at traffic light 3, the pulse operation of relay 2I stops, the BS-DA decoder is turned off, relay Zh is de-energized, it turns off its repeater Zh1, and relay Zh1 in turn de-energizes repeaters Zh2, Zh3. At the crossing, the IP relay is de-energized by the contacts of the signal relay repeater Zh1, and the IP relay de-energizes the PIP relay. At the same time, at traffic light 3, through the rear contact of relay Z3, the OI relay is triggered, which, when triggered, prepares the coding circuit of the track circuit 3P, following the departing train. The transmission of the KZh code after the departing train occurs from the moment the traffic light 3 has completely passed. When the train enters section 3P, the counting circuit is activated at the crossing, relays 1C, B1ZH, B1Z, B are energized.

The first to operate is the counter relay 1C, along the chain: front relay contacts NIP, 1N, K, Zh1, and rear relay contacts 1IP, PIP.

After relay 1C has triggered, it prepares the switching circuit for relays B1ZH, B1Z, they operate only after the train enters section 3Pa. When the train enters 3Pa, the operation of the pulse relays stops: 2I, the general repeater I, and the transmitter relay 1T, and the decoder also stops working. The decoder turns off relay Zh, Z, relay Z turns off 1PT and K, relay contact Z turns off the NIP relay. From the moment the section 3P at the crossing is completely freed from the KZh code pulses coming from traffic light 3, relays 1I and DI begin to operate. It is energized by the DP relay and closes the front contact in the power supply circuit of relay 1 IP. 1IP is energized. After the train completely clears section 3P, the blocking relay circuit is activated. 1IP becomes energized and de-energizes the power circuit of relay 1C with its front contact.

Relay-counter 1C has a drop-off delay, due to this, a charging circuit for capacitors BK2 and BK3 is created, as well as an excitation circuit for relay B1Zh.

After this, relay B1Zh becomes energized. After the relay-counter 1C is de-energized, the charging circuit of capacitors BK2, BK3 is interrupted. The front contact of relay B1Z and through the rear contact Z1 closes the excitation circuit of relay B and the charge of capacitor BK1. Relay B opens the power circuit of relay B1Zh. After some slowdown, relay B1Zh will de-energize and turn off relay B. After capacitor BK1 discharges, relay B releases the armature and again closes the excitation circuit of relay B1Zh.

The operation of the blocking relays B1Z and B begins after the complete release of section 3Pa, from this moment the KZh code is supplied from traffic light 4 to the 3Pa rail circuit, at the crossing in the KZh code mode, relay 2I begins to operate, then the general repeater I is triggered, then the decoder is turned on, they stand up under current relay Zh, Zh1, relay 1PT. The charging circuit of the capacitance BK4, BK3 is closed, passing through the front Zh1, rear Z, and the front 1PT, DP, B1Zh, relays B1Z and B are activated.

B1Zh will be de-energized due to the discharge of capacitance BK3, BK2. The blocking relays continue to operate until the second removal section is completely freed.

In the event of a violation of the estimated time for the train to pass through the second removal section, the operation of relays B1ZH, B1Z, B is stopped, relay contact B turns off the NIP, the NIP relay turns off relay IP1, the crossing remains closed, the crossing will open only when the train moves away from the traffic light two block sections.

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Introduction

1. Operational part

1.1 Overview of crossing systems

1.2 Devices and main elements

2. Technical part

2.2 Calculation of the length of the section approaching the crossing

2.3 Algorithm for unguarded crossings

2.4 Scheme of notification of the approach of a train to a crossing

2.5 Traffic light signaling diagram

3. Technological part

3.1 Types of maintenance work for automation devices at crossings

3.2 Maintenance automation devices at crossings

4. Economic part

4.1 General provisions

4.2 Calculation of the level of labor productivity for the reporting and base periods

4.3 Determination of the number of technical distance units

5. Detail of final qualifying work

5.1 UZP device (Crossing barrier device)

5.2 Operating principle of the UZP (Crossing Barrier Device)

6. Occupational safety and environmental issues during the operation of signaling devices for guarded and unguarded crossings

6.1 Occupational safety when operating alarm devices

guarded and unguarded crossings

6.2 Environmental issues

List of used literature

Applications

Introduction

There are currently two main automatic blocking systems in use on the road network. In areas with autonomous traction, automatic blocking with impulse rail circuits is used DC. On lines with electric traction, coded automatic blocking with track chains is used AC frequency of 50 Hz in areas with DC electric traction and 25 or 75 Hz on lines with AC electric traction. With the introduction of high-speed traffic, new requirements appeared to ensure the safety of train traffic, the need to reduce operating costs for maintenance, and increase the reliability of devices, which led to the creation of a new element base, new automatic blocking systems. When developing new systems, the shortcomings of existing automatic blocking and automatic locomotive signaling systems were taken into account, such as: unreliability and instability of the track circuit due to low ballast resistance; complication of the operation of the track circuit due to the need to channel the traction current with the connection of choke transformers and the occurrence of dangerous and interfering influences of the traction current; decentralized placement of equipment; the possibility of passing prohibiting traffic lights, and others. New systems have been created, such as the multi-valued ALSN, the automatic brake control system SAUT. New systems are built on new element base using integrated circuits and tone rail circuits. Automatic blocking with tone track circuits has high reliability, a high coefficient of return of the track receiver, high noise immunity and protection from the influence of traction current. Based on tone rail circuits, a number of automatic blocking systems with decentralized and centralized placement of tone control centers have been developed and operate.

At the intersections of iron and highways construct railway crossings. To ensure the safety of trains and vehicles, crossings are equipped with fencing devices to create conditions for the unhindered movement of trains and to prevent collisions between trains and vehicles traveling along the road. Depending on the intensity of traffic at crossings, fencing devices are used in the form of automatic traffic light signaling; automatic crossing alarm with automatic barriers; automatic or non-automatic warning alarm with non-automatic (mechanical with manual or electrical with remote control) barriers. Railway crossings equipped with automatic traffic light signaling devices can be guarded (serviced by a crossing duty officer) or unguarded (without a crossing duty officer). In accordance with the requirements of the Rules technical operation railways Russian Federation automatic crossing alarms must provide a stop signal in the direction of the road, and automatic barriers must assume a closed position in the time required for the advance clearing of the crossing by vehicles before the train approaches the crossing. crossing barrier alarm automatic

It is necessary that the automatic traffic light signaling continues to operate, and the automatic barriers remain in the closed position until the crossing is completely cleared by the train. To fence off the crossing, crossing traffic lights are installed on both sides of the crossing at a distance of at least 6 m from the outermost rail. With automatic crossing signaling with automatic barriers, crossing traffic lights are combined with auto barriers, which are installed at a distance of at least 6 m from the outer rail with a beam length of 4 m or at a distance of at least 8 and 10 m with a beam length of 6 and 8 m, respectively.

Automatic or non-automatic warning signaling is used to provide the crossing officer with audible and optical signals about the approach of a train. Barrier signaling is used to signal a train to stop in the event of emergency situation on the move. In order to promptly close the crossing when a train approaches, approach sections equipped with rail chains are installed. The main ways to develop automatic crossing signaling are to ensure complete and timely safety of trains and road transport. A reliable means of ensuring traffic safety at a crossing is the introduction of crossing barrier devices, with the help of which the roadway is blocked for cars (automatic barriers and crossing barrier devices). The second, more reliable means of ensuring train safety is the construction of roads and railways at different levels.

1. Operational part

1.1 Overview of crossing systems

Railway crossings are among the places with the greatest danger for the movement of both types of transport and therefore require special fencing. Taking into account the great inertia of railway rolling units, pre-emptive right traffic at crossings is provided to railway transport. Its unhindered movement along the crossing is excluded only in the event of an emergency. In this case, a special barrier alarm with automatic or non-automatic action is provided. Crossings in the direction of vehicle traffic are constantly equipped current means fencing. For this purpose, the following devices are used: automatic crossing traffic light signaling with automatic barriers (APSh); automatic crossing traffic light signaling without auto barriers (APS); Alert crossing alarm (OPS), which only gives notification to the crossing about the approach of a train; mechanized and electrically driven non-automatic barriers; warning signs and plates. Railway crossings are divided into 4 categories, which are determined by the nature and intensity of traffic at the crossing, the category of the road at the intersection and visibility conditions. The intensity of traffic at a crossing is estimated by multiplying the number of trains and the number of vehicles passing through the crossing during the day. Visibility at a crossing is considered satisfactory if a train is visible from a vehicle located 50 m in front of the crossing at a distance of 400 m from the crossing, and the crossing is visible to a locomotive driver at a distance of more than 1000 m. The choice of crossing fencing devices on the road side depends on its category and the maximum speed of the train on the section. The nearest stretch and station traffic lights are used as barrier traffic lights, and in their absence, special ones are installed.

1.2 Design and main elements

Crossings, as a rule, are arranged on straight sections of railways and highways intersecting at right angles. In exceptional cases, it is allowed to cross roads at an acute angle of at least 60° degrees. In the longitudinal profile, the highway must have horizontal platform for at least 10 m from the outermost rail on the embankment and 15 m in the excavation. According to the existing international classification At railway crossings, as objects of greatest danger, a special signal is adopted to transmit a command to prohibit the movement of vehicles - two red lights that turn on alternately. On railways In Russia, crossing traffic lights are used for this purpose. special design. If there is no train in the areas approaching the crossing, the lamps in the traffic light heads are extinguished, which gives the right to vehicles to move through the crossing in compliance with the precautions provided for by the traffic rules. Crossing traffic lights are installed on the right side of the road at a distance of at least 6 m from the head of the outermost rail. At the same time, good visibility of its vehicles must be ensured so that a road train moving at maximum speed can stop at a distance of at least 5 m from the traffic light. Automatic barriers block the roadway when a crossing is closed and mechanically impede the movement of vehicles. Currently, half-barriers are predominantly used, blocking from 1/2 to 2/3 of the roadway in the direction of vehicle traffic. On the left side of the road, a strip with a width of at least 3 m must remain unblocked. To ensure the timely opening of the crossing after it is cleared by a train, additional iso-joints are installed at the crossing, isolating the activation of warning alarms on the network and limiting the length of the RC approach sections. Existing DCs without additional insulating joints can be used for switching off if their insulating joints are located on single-track sections at a distance of no more than 40 m from the crossing; on double-track sections - no more than 40 m before the crossing and 150 m behind the crossing. Approach areas near crossings can be equipped with overlay control centers. APS systems with two-way permanent signaling both towards the road and towards the railway have been developed and are widely used in industrial railway transport. The alarm system is built on a mutually exclusive principle: a permissive indication at road traffic lights is possible only with prohibitive indications at railway traffic lights and vice versa. This allows you to maintain an acceptable failure rate when using elements below the first reliability class. Equipping industrial transport crossings with such systems allows, in particular, to increase the throughput of railway sections by increasing the speed of trains through the crossings. In mainline transport, the use of such systems is possible provided that bandwidth railway sections on which crossings are located. IN existing systems ah APS methods for automatically controlling fencing devices at crossings located on a stretch depend on their location relative to the entrance and passage traffic lights, the type of AB and the nature of train movement (one-way or two-way). This is due to the wide variety of existing types of crossing installations, differing mainly in control schemes and coupling with AB. Thus, for crossings on a double-track section with numerical code automatic blocking, 10 types of crossing signaling control schemes have been developed. On single-track sections with a numerical code AB, the number of such types of crossing installations increases even more. The types of installations differ mainly in notification schemes, i.e., in the method of sending commands to the crossing to turn on and off the crossing alarm. Schemes for direct control of alarms and auto barriers remain virtually unchanged, which is very important for construction and installation work and maintenance. At the same time, notification schemes for crossings, as well as control schemes for fencing devices, are constructed to ensure the greatest possible versatility, sometimes through some complication. At crossings located on a stretch with a numerical code AB, two-wire linear circuits are used for notification, since the RC receiving devices are located at the input ends. Depending on the estimated length of the approach section, the notification circuit connects the crossing with one or two nearest signal installations in each direction of movement. When a train enters the approaching section, a command is given through the crossing notification circuit to close the crossing. If the actual approach section is larger than the calculated one, then the command is executed with a corresponding time delay. The command to move about the opening is sent after the train has passed through the DC. To do this, a train moving towards the crossing receives code signals, which are perceived at the crossing after it is cleared. Fencing devices are restored to their original state. The previously sent command to close the crossing is canceled completely only after the train has completely vacated the block section on which the crossing is located.

1.3 Types of crossings and their technical equipment

Crossings are intersections of highways and railway tracks at the same level. The simplest way ensuring the safety of the movement of vehicles through the crossing consists of giving manual signals to the crossing guards about the approach of a train and closing the barrier with a mechanical winch. The crossing duty officer performs these actions after a telephone notification to the station duty officer about the start or upcoming movement of the train, in connection with which this method has the following disadvantages: unnecessary downtime of vehicles due to premature closure of the crossing; the dependence of traffic safety at the crossing on the coordination, correctness and timeliness of the actions of those on duty at the station and the crossing. Therefore, automatic crossing fencing devices are widely used, which include automatic crossing alarms with or without auto barriers and automatic crossing (notification) alarms with electric barriers or mechanized barriers controlled by the crossing duty officer. The large number of crossings on the railway network and the growth in traffic volumes by all modes of transport determine the need for significant funds and time for the construction of crossing signaling. Therefore, depending on local conditions, it is necessary to use various methods to ensure traffic safety at crossings. Crossings are divided into four categories and can be regulated or unregulated. At regulated crossings, traffic safety is ensured by crossing signaling devices or an employee on duty, and at unregulated crossings - only by vehicle drivers. Guarded crossings are those where there is an employee on duty.

A crossing alarm with an employee on duty is used at crossings: through which trains move at a speed of more than 140 km/h; located at the intersections of main tracks with roads along which tram or trolleybus traffic occurs; Category I; Category II, located in areas with a traffic intensity of more than 16 trains/day, not equipped with automatic traffic lights with green or moon-white lights. At crossings that are not equipped with crossing alarms, the movement of vehicles is regulated by an employee on duty following cases: when trains move at speeds over 140 km/h; at the intersection of three or more main paths; when main tracks cross roads with tram and trolleybus traffic; at crossings of category I; at crossings of category II with unsatisfactory visibility conditions, and in areas with a traffic intensity of more than 16 trains/day, regardless of visibility conditions; at III category crossings with unsatisfactory visibility conditions, located in areas with a traffic intensity of more than 16 trains/day, as well as located in areas with a traffic intensity of more than 200 trains/day, regardless of visibility conditions. Crossing security, as a rule, should be around the clock. Crossings guarded 24 hours a day must be equipped with barriers, and crossings guarded in one shift with a crossing alarm can be operated without barriers. Unguarded crossings at stretches and stations must be equipped with automatic traffic lights, with or without green (moon-white) light.

a) without an employee on duty b) with an employee on duty

Crossing traffic lights are installed on barrier pedestals or separately on masts on the right side of the road at a distance of at least 6 m from the head of the outer rail, providing good visibility to vehicle drivers. The figure shows crossing traffic lights for unattended and manned crossings.

In the first case, the movement of vehicles through the crossing is permitted when the crossing traffic light is green (moon-white), and is prohibited when there are two red flashing lights. The extinguishing of all lights indicates a malfunction of the crossing signaling, and the driver of a road vehicle, before proceeding through the crossing, must make sure that there are no trains on the approaches to the crossing. In the second case, flashing red lights prohibit movement through the crossing, and when they are turned off, ensuring the safe passage of the crossing is the responsibility of road transport drivers. Guarded crossings on stretches are equipped with automatic traffic lights with or without green (lunar-white) lights and automatic barriers. Guarded crossings at stations are equipped with warning alarms with green (moon-white) lights and semi-automatic electric barriers, which close automatically and are opened by pressing a button by the employee on duty. In exceptional cases, it is allowed to use automatic warning alarms with electric barriers.

Barrier alarms are installed at guarded crossings. As barrier traffic lights, you can use station and stage traffic lights located from the crossing at a distance of no more than 800 m and not less than 16 m, provided that the crossing is visible from the place of their installation. If the traffic lights listed above cannot be used, then barrier traffic lights should be installed at a distance of at least 15 m from the crossing. Barrier traffic lights are installed on single-track sections on both sides of the crossing, and on double-track sections along the correct path. Obstacle traffic lights are installed along the wrong path in the following cases: on double-track sections equipped with double-sided automatic parking; when regularly driving along the wrong path; in suburban areas of large cities with traffic exceeding 100 pairs of trains/day. Installation of traffic lights to prevent trains from moving along the wrong track is allowed on the left side.

At crossings located on double-track sections and equipped with barrier signals for movement only on the correct path, the head of the road establishes a procedure in which the prohibiting indication of barrier traffic lights for movement on the correct path is also a stop signal for trains traveling on the wrong path.

If the required visibility of the barrier traffic light is not ensured, then in areas not equipped with AB, a warning traffic light is installed in front of such a traffic light, the same in shape as the barrier traffic light and giving a yellow signal when the main traffic light is red and not lit when the main traffic light is extinguished. All guarded crossings located in areas with AB must be equipped with devices for switching the AB traffic lights closest to the crossings to prohibitive indications when an obstacle to train movement occurs.

Guarded crossings on access roads and other tracks, where approach areas cannot be equipped with rail chains, are equipped with traffic light signaling with electric, mechanized or manual barriers, and unguarded crossings are equipped with traffic light signaling. In both cases, traffic lights with red and white lights are installed, controlled by the worker on duty, the drafting (locomotive) crew, or automatically when the train enters the sensors.

2. Technical part

2.1 Installation and control diagram of the PASH-1 barrier

The barriers must block at least half of the carriageway of the road on the right side so that on the left side the carriageway of the road with a width of at least 3 m remains unblocked. Mechanized barriers must block the entire carriageway of the road and have signal lights that are lit at night. The lights should show red lights towards the highway when the barriers are closed and transparent white lights when the barriers are open, and towards the railway track - transparent white lights at any position of the barriers.

Barriers are installed on the right side on the side of the road on both sides of the crossing at a height of 1 - 1.25 m from the surface of the roadway. In this case, mechanized barriers are installed at a distance of at least 8.5 m from the outermost rail; automatic and electric barriers are installed at a distance of at least 6, 8 and 10 m from the outer rail, depending on the length of the barrier beam (4, 6 and 8 m). In case of damage to the main ones, it is necessary to install spare manual barriers at a distance of at least 1 m from the main ones towards the road. These barriers must cover the entire carriageway of the road and have devices for securing them in both positions and hanging a lamp. According to the method of powering the electric motor (EM), there are three versions of barriers: three-phase, single-phase (alternating current) and direct current. A barrier of the PAS-1 type is a set of devices (see Appendix 1) that transmit to vehicle drivers and pedestrians through optical (signals of crossing traffic lights and barrier bars) and audible (bell signal) alarms an order to allow or prohibit movement on the crossing.

An electric drive (ED) 3 is installed on the stand 11 located on the foundation 2. The CB 4 is fixed in a frame 5, on which a turning device 6 is located, which allows, when a vehicle hits the CB, to turn it in the horizontal plane at an angle of 90° degrees along the direction vehicle traffic. A counterweight 7 is installed on the frame 5, which creates a certain coordinate of the center of gravity of the “ZB frame - counterweight” system on the plane of motion of the CB. The barrier can be equipped with traffic light 8 and bell 9.

The normal position of automatic barriers, in most cases, is open. Guarded crossings must have a direct telephone connection with the nearest station or post, and in areas equipped with a DC, with a train dispatcher and, if necessary, radio communication.

When a train enters the approaching section, the red flashing lights on the crossing traffic lights and barrier bars of the barriers light up, the bell turns on, and after the time (approximately 16 s) required for the vehicle entering the crossing to follow the barrier, the electric drives begin to lower their bars. After the train clears the approaching area and moves, the automatic fencing devices again take their original position. Operation of PAS-1. It is very important to note that the PASH-1 barrier can also be used as an electric barrier operating outside automatic mode. A special feature of the PAS-1 auto barrier is the design of the barrier drive, which provides maximum ease of maintenance and replacement of drive elements, and the use of a metal barrier bar, which prevents its breakage when colliding with vehicles and lowering of the bar under the influence of its own weight.

The last condition adopted during the development of the auto barrier made it possible to use an AC motor to control the auto barrier. The use of the auto barrier drive design, which ensures the lowering of the barrier beam under the influence of its own weight, made it possible to abandon the backup of alternating current from batteries while providing power to the crossing from two independent sources.

A design feature of the PAS-1 auto barrier is the absence of a crossing traffic light combined with the auto barrier. In this regard, with a new design it is necessary to provide for the additional installation of a separate crossing traffic light.

Automatic barrier PAS-1 should be installed, as a rule, between a crossing traffic light and a fenced railway track, ensuring compliance with the required dimensions.

In cases where, when replacing an auto barrier in existing devices, it cannot, due to the clearance conditions, be installed between the retained traffic light and the railway track, the PASH-1 auto barrier is installed in front of the traffic light. In this case, when calculating the notification time, the length of the crossing should be increased accordingly. Main characteristics of the PASH-1 auto barrier. When developing technical solutions 419418-00-STSB.TR “Control circuits for a crossing barrier with an AC motor PAS-94”, the following basic provisions were adopted.

The barrier beam is raised by an AC electric motor. Motor - asynchronous three-phase, switched on single-phase circuit(capacitor start). AC voltage 220 V, rated power 180 W, AC frequency 50 or 60 Hz. Lowering of the barrier beam is free, under the influence of its own weight. Lowering occurs when power is removed from the electromagnetic clutch.

Switching off the electric motors when lifting the beam at an angle of 80-90 and monitoring the horizontal position of the beam is carried out by relay contacts operating through the autoswitch contacts.

To protect the electric motor from overheating during long ascents (motor operation using friction), the engine is switched off after a delay of 20-30 s.

For traffic light signaling at crossings, in addition to the auto barrier, it is planned to install a separate crossing traffic light. When replacing a car barrier in existing devices, as a rule, the existing traffic light must be retained.

PAS-1 is powered only from AC sources and does not require battery backup. The battery is provided only to backup the power supply for traffic light lamps of crossing and barrier traffic lights, relay circuits, and, if necessary, track circuits.

When the alternating current is turned off, the beam is raised to a vertical position for the passage of road transport by the person on duty at the crossing manually, directly by lifting the beam or using a curler. The algorithm for turning on the traffic light signal and lowering the bar of the auto barrier and the ability to maintain the bar upon receipt of notification of the approach of a train are preserved as for existing standard solutions and devices.

Technical solutions contain diagrams for new design, as well as diagrams for linking the PAS-1 auto barrier with existing devices, taking into account the need for maximum preservation of equipment, diagrams and minimal rewiring.

Control circuit for automatic barrier PAS-1 (see Appendix 2) All circuits are made using REL or NMSh relays.

The electromagnetic clutch of the EM auto barrier is normally energized and ensures the coupling of the beam with the gearbox and keeping the beam in a raised state. The electric motor of the auto barrier M is three-phase, phase C2-C5 is isolated, and phase C3-C6 with series-connected capacitors with a capacity of 15 μF is connected in parallel to phase C1-C4. When the AC power is turned on, this allows the motor to rotate. The BC block contacts ensure that the engine is turned off in the event of turning the crank flap, when it is necessary to open the drive cover or lift the barrier beam with the crank handle. Bl, B2 - auto-switch contacts that control the lowered and raised position of the auto-barrier beam, respectively.

The circuit relays have the following purposes:

The VM provides a time delay for lowering the car barrier beam after the red flashing lights at the crossing traffic light are turned on (13 s); VEM - electromagnetic clutch switch-off relay; OSHA, OSHB - opening relay (turning on the lifting of the beam) of the VED auto barrier - time delay relay 20-30 s to turn on the engine when working with friction. U1, U2, U3 - relay for monitoring the raised state of the bars of auto barriers. ZU - relay for monitoring the lowered (closed position) of the bars of auto barriers; IN YES, VDB - relays-repeaters of autoswitch contacts, controlling the intermediate position of the bars of auto barriers and ensuring that the engines are turned off; UB1, UB2 -- repeater relays of the auto barrier beam maintenance button; PV 1, PV2 - relays that turn on the crossing alarm.

One of the design features of the PASH-1 auto barrier is that the autoswitch contacts used in it do not allow the value of the permissible current load to control power circuits. This required the use of relay repeaters of their contacts.

Normally, in the absence of trains, the bar of the car barrier is in a raised state. Relays OSHA, OSHB, VED, V DA, VDB and ZU are in a de-energized state. Relays U1, U2, UZ, VEM and VM, and an electromagnetic clutch are under current.

The command to turn on the electric drive is given by occupying the track circuit of the section approaching the crossing by train or manually from the control panel.

When a train enters the approach section, relays PV1 and PV2 (not shown in the diagram), which are repeaters of the relays of the approach detectors, are de-energized. With their contacts they open the power circuit of relays U1 and U2, Relays U1 and U2 with their front contacts open the power circuit of the relay VM, which in for 13-15 s it will hold the armature due to the energy stored by a 3400 µF capacitor connected in parallel to its winding.

At the same time, the contacts of relays U1, U2 and their UZ repeater turn on the red lights at crossing traffic lights and activate a set of relays that provide power to the lights in a flashing mode, signaling towards the road.

The time delay for releasing the armature of the VM relay is necessary so that vehicles that have started moving before the red lights at crossing traffic lights turn on have time to pass under the beam. After some time necessary for the passage of the vehicle previously moving under the barrier, it releases the armature of the VM relay and with its contacts opens the power supply circuit of the VM relay. The latter opens the power supply circuit of the electromagnetic clutch. The car barrier beam begins to fall under the influence of its own weight. After it takes a horizontal position, close contacts B1 of the automatic barrier drive switch. At the same time, the charger relay is energized, signaling the closed position of the auto barrier. When a train enters the approaching section through the rear contacts of relays U1, U2 and relay PV1. PV2 will receive power and attract the armature of the VED relay, in parallel with which a high-capacity capacitor is connected. The VED relay will prepare the excitation circuit for the opening relay of the OSHA and OSHB auto barriers.

After the train passes the crossing, the armature of relays PV 1 and PV2 is pulled in, the power circuit of the VEM, OSHA and OSHB relays is closed. The VEM relay will turn on the electromagnetic clutch, and the OSHA and OSHB relays will close the power supply circuit for the electric motors that drive the bars of the auto barriers. As a result, the latter will begin to rise to a vertical position. After both beams reach a vertical position (80-90 degrees), the contacts of autoswitches B2 close and create a power circuit for relays U1, U2 and their ultrasonic repeater. They, in turn, will open the power circuit of the OSHA and OSHB relays, and the circuit will return to its original state.

If for any reason (for example, when jammed) one of the auto-barrier bars (auto-barrier B) stops in the middle position, then after the auto-barrier bar A reaches a vertical position, it will attract the armature of the VDA relay. With its contacts it will open the power supply circuit of the OSHA relay, which in turn will open the power supply circuit of the engine. The OSHB relay will remain energized and the auto barrier drive motor B will operate in friction until the discharge of a capacitor with a capacity of 9000 μF, connected in parallel to the coil of the VED relay, ends, and the latter releases its armature.

If the AC power is turned off, the bars of the auto barriers will remain in the raised position until the first train approaches the crossing. After this, the bars will be lowered automatically, and they will be raised manually after the train has passed.

If there is no battery at the crossing, the bars of the auto barriers will lower simultaneously with the AC power being turned off. The battery has a nominal voltage of 14V (seven ABN-72 batteries). To charge the battery, an automatic current regulator of the PTA type is used, which ensures the battery is charged in continuous charging mode.

The crossing is powered by single-phase alternating current from two independent sources, one of which is the main one, the second is a backup one. When a guarded crossing is located on a stretch equipped with automatic blocking, the high-voltage power supply line for signaling devices (VL SCB) serves as the main power source, and the high-voltage longitudinal power supply line (VL PE) serves as a backup source.

At the input of AC power supplies into the relay cabinet of the crossing, 20A fuses are installed, acting as switches. The presence of supply voltage from both sources is controlled by emergency relays A (main) and A1 (backup). Normally, power is supplied from the main source, when the load is turned off, the contacts of emergency relay A switches to the backup source.

2.2 Calculation of the length of the section approaching the crossing

In accordance with the requirements of the Rules for the Technical Operation of Railways of the Russian Federation, automatic crossing signaling must provide a stop signal in the direction of the highway, and automatic barriers must assume a closed position in the time required for the advance clearing of the crossing by vehicles before the train approaches the crossing. It is necessary that the automatic traffic light signaling continues to operate until the crossing is completely cleared by the train. The crossing must be closed in a timely manner, for this purpose the following calculations are made: - Let’s determine the time required for the car to complete the crossing:

Т1 = (Lп + Lр + Lс) / Vр

where, Lп = crossing length, determined by the distance from the crossing traffic light furthest from the outer rail to the opposite outer rail; Lр - design length of the vehicle; Lс is the distance from the place where the car stops to the crossing traffic light; Vр is the estimated speed of the vehicle through the crossing. - Let us determine the required time of notification about the approach of the train to the crossing:

where T1 is the time required for the car to cross the crossing; T2 equipment response time, s; T3 - guaranteed time reserve. - Let's determine the length of the approach section:

Lр = 0.28Vmax Тс = 0.28Vmax (Lп + Lр + Lс) / Vр + Т2 + Т3

Where, 0.28 is the speed conversion factor from km/h to m/s; Vmax is the maximum speed of trains specified on a given section. According to established standards, the notification time of a train approaching a crossing must be at least 40 s with the AGSh and APS systems, and with the OPS warning system - 50 s. Automatic rail blocking circuits are used to transmit notification of the approach of a train to the crossing. To open the crossing after it is vacated by the last carriage of the train, the track chains at the crossing are divided into two parts. The first part of the split rail circuit before the crossing is used to form an approach section, upon entering which the crossing is closed; the second part behind the crossing is used as a removal area when the direction of movement is correct or as an approach area when the direction of movement is incorrect. After the approach section is cleared and the train enters the departure section, the crossing opens. Determination of the estimated lengths of approach sections Lp for double-track automatic blocking (see Appendix 3). From traffic light 6 to the crossing, the length of the rail circuit 6P is equal to the calculated length Lp, therefore the actual length of the approach section is equal to the calculated one. The approach section starts from traffic light 6 and is formed by rail circuit 6P; the removal area is formed by a 6Pa rail chain. From traffic light 5 to the crossing, the length of the track circuit 5P is less than the design length Lp; therefore, part of the track circuit 7P is included in the approach section. At the boundary Lp, the track chain does not have a cut, and it is impossible to detect the entry of a train onto this boundary. Therefore, the actual length of the approach section is determined before traffic light 7 and is equal to the length of the rail circuits 7P and 5P. In this case, the actual length of the approach section exceeds the calculated one and an excessive length of the approach section is obtained

Due to the excessive length, the notification time increases, the crossing closes prematurely, which leads to delays in the movement of vehicles through the crossing. To reduce the loss of time, time delay elements are used in APS control devices so that the time delay for closing the crossing is equal to the time it takes a train traveling at maximum speed to pass the section determined by the difference between the actual and estimated length of the approach sections. However, when the train moves at a lower speed, the endurance turns out to be insufficient, the notice for the crossing increases, and vehicle delays increase. In all cases when the calculated section Lp is formed from two rail circuits, two sections of notification are received: from the crossing to the first traffic light and from the first to the second traffic light. A notice to close a traffic light is given two sections of the approach.

2.3 Algorithm for the operation of an unguarded crossing

Appendix 4 provides an algorithm for the operation of an unguarded crossing. At the moment the train enters the approach section, which is checked by operator 1, obstacle detection devices in the crossing area (OPA) are connected to the APS system, the train movement parameters speed and, acceleration a and coordinate / are measured, and based on these parameters the distance lmin from the train to crossing, upon reaching which the crossing must be closed. These actions are performed by operators 2, 3. When the train is at the point with coordinate Imin, a command is given to turn on the warning alarm (operator 2), including red flashing lights at crossing traffic lights. Their proper operation is checked by operator 3.

If there is an obstacle at the crossing (stuck vehicles, fallen cargo, etc.), emergency braking of the train (operator 5). If not, the train proceeded through the crossing (operator 7). After the train has passed and in the absence of a second one in the approaching section (operator 8), the warning alarm is turned off (operator 9). The APS system returns to its original state.

2.4 Schemes for notifying trains approaching crossings

In areas with automatic blocking, track circuits are used to control crossing signaling. In this case, depending on the location of the traffic lights relative to the crossing, notification of the approach of a train may be received one or two block sections ahead. To automatically turn off the crossing signaling after a train has passed the crossing, additional insulating joints are installed, except in cases where the crossing is located in close proximity to the automatic blocking signaling installation. Schemes for notifying trains approaching crossings vary significantly depending on the type of automatic blocking used at the site. On double-track sections with one-way automatic blocking, automatic control Crossing signaling is carried out only when trains are moving on the correct track. In case of movement on the wrong path, the crossing signaling circuits ensure the transmission of code pulses of the automatic locomotive signaling, bypassing additional insulating joints, but the crossing signaling is controlled manually.

Let's consider a control scheme for crossing signaling for double-track sections with automatic DC blocking, (graphical part, sheet 1) in relation to the movement of trains along an even track. The complete crossing signaling control circuit consists of two identical (even and odd) circuits.

When track circuits 8A and 8B are free, DC pulses from the rectifier VAK-14 of traffic light 8 enter track circuit 8A and cause pulsed operation of the track relay CHI. Through the contact of its repeater CHI2, DC pulses are transmitted to the track circuit 8B and cause pulsed operation of the traffic light track relay 6. The emergency relay of the relay decoder receives power and turns on the CHIP approach notification relay. Through the relay contact, the CHIP receives power from the CHIP1 relay, which turns on the CV crossing alarm control relay. As a result, traffic lights 6 and 8 have permissive signal indications, and the crossing is open to vehicle traffic.

The approach of the train to the calculated distance to the crossing causes the CHIP relay to turn off. If it is necessary to transmit a notification over two block sections, the CHIP relay is connected by a linear circuit to the relay cabinet of the traffic light 8 and is switched off by the contacts of the travel relay 8P. In case of notification of the approach of a train in one block section, the CHIP relay becomes a repeater of the emergency relay.

Turning off the CHIP relay leads to the de-energization of the CV relay, which has a delay in releasing the armature. Adjusting the deceleration by changing the capacitance of capacitor C makes it possible to eliminate premature closure of the crossing due to excessive removal of insulating joints from the crossing. After capacitor C is discharged, the CV relay will release the armature and turn on the crossing alarm.

Entry of a train onto track circuit 8A causes an interruption pulse work relay CHI and CHI2. DC pulses stop flowing into track circuit 8B. As a result, alternating current pulses necessary for the operation of the automatic locomotive alarm begin to flow from the power supply of the traffic light 6 into the rail circuit 8B. These pulses are perceived by the CHT relay, repeated by the CHT transmitter relay and transmitted to the track circuit 8A towards the movement of the train. The crossing signaling is switched off when the train releases track circuit 8A. The CHI relay in this case begins to receive direct current pulses entering the track circuit 8A from the power supply of the traffic light 8. This causes the FC and CHIP relays to turn on, and the heating of the thermal element of the CHI relay. Thus, the operation of the CHIP1 relay will occur with a time delay of 8-18 s, which is necessary to prevent premature opening of the crossing in the event of a short-term loss of the train shunt in the 8A track circuit. The CHIP1 relay will turn on the CHV relay, and the latter will open the crossing for vehicle traffic.

Relays DC, ChD, ChDKV and ChDT are used to broadcast ALS codes when trains are moving in the wrong direction in case of temporary two-way traffic.

On single-track sections, the crossing signaling must be turned on when trains are moving in both directions, regardless of the set direction of the automatic blocking. Notification of a train approaching a crossing in a specified direction, as on double-track sections, can be transmitted in one or two block sections of approach, and in an unspecified direction - only in two. Crossing alarm in the established direction, it is turned off after the train has passed the crossing, and when the train is moving in an unspecified direction, after it has passed the crossing and the area approaching the established direction is cleared.

2.5 Switching diagram for traffic light signaling

At crossings equipped with automatic traffic light signaling (graphic part, sheet 2), the crossing traffic lights and bells turn on the switching relay B and its repeater PV. When the approach area is free, relays B and PV are excited, the signal lamp and bell circuits are open, the flashing relay M and the control CM are turned off. The serviceability of the signal lamp threads of traffic lights is controlled by the fire relays AO and BO.

Each of them monitors the serviceability of two signal lamps located at different traffic lights, in a cold state and when burning. The AO relay, with an open crossing and serviceable lines, receives power through a high-resistance winding through a circuit passing through the front contacts of relay B and the series-connected lamps 1L of traffic light A and 2L of traffic light B. The BO relay is switched on in the same way. From the moment the train enters the approach section, relays HB (ChV), B and PV are sequentially switched off. The rear contact of relay B turns on the pendulum transmitter MT, relay M begins to operate in pulse mode, relay KM is excited, relay KMK remains in the excited state. The rear contacts of the PV relay turn on the bells installed on the masts of crossing traffic lights. Relay contacts B in the lamp circuits turn on the low-resistance windings of the fire relays instead of the high-resistance ones, and the traffic light lamps light up, prohibiting the movement of vehicles. The flashing mode of the lamps is ensured by switching the relay contacts M in their circuits. By the front contacts of relay M, lamps 1L on both traffic lights are bypassed, and lamps 2L light up when the armature of relay M is released, lamps 1L are turned on. After the train clears the approaching section, the NV (ChV), B and PV relays are sequentially excited. The MT transmitter, relay M and KM are turned off. In the circuit of traffic light lamps, the high-resistance windings of the fire relays AO and BO are switched on, and the traffic light lamps go out. The bells are turned off and the crossing is opened to vehicle traffic. In the control circuits of the main control panel of the dispatch control, the contacts of the fire relays DSN, KMK, PV and emergency A are switched on.

2.6 Scheme for switching on the moon-white light

To increase the safety of trains and vehicles at unguarded crossings, crossing traffic lights are equipped with an additional traffic light head with a Moon-white flashing light (see Appendix 5), which lights up when the crossing is open and in good working order and turns off when a train approaches it. The serviceability of the moon-white lamp circuit is checked in the burning and cold states using the BLO fire relay. If the approaching area is free, relays B, PV are excited, including relays VBA, VBB, as well as relays KM and KMK. The MT transmitter is constantly turned on, since when the crossing is open, the moon-white lamps should be on in a flashing mode, and when the crossing is closed, red. The MBO relay operates in pulse mode through the MT contact. When the MBO relay (TSh-65V) is excited, the low-resistance winding of the fire relay is switched on in series with the moon-white fire lamp, and the lamp lights up, and when the armature of the MBO relay is released, both windings are turned on in series, the lamp goes out. From the moment the train enters the approaching section, the NV (ChV), V, PV, VBA, VBB relays are switched off. In pulse mode, relays M, Ml, M2 begin to operate, and relay KM1 is excited. Relay MB O continues to operate in pulse mode through relay contact M2. The KM and KMK relays remain energized. The moon-white light lamps are turned off by the VBA and VBB relay contacts (traffic light lamp B is not shown in the diagram). The rear contacts of relay B and PV turn on the red light lamps and bells. The crossing is closed. After the train passes and the crossing is cleared, the NV (ChV), V, PV, VBA, VBB relays are turned on. Relays M, Ml, M2 and KM1 are turned off. At crossing traffic lights, the red flashing lights turn off and the moon-white flashing light turns on; the crossing is open to vehicle traffic. Information about the serviceability of the lamp filaments of the flashing red and moon-white lights of crossing traffic lights is transmitted through the dispatch control circuit through the GKSh unit to the nearest station. If there is damage at the distillation unit (traffic light lamp burns out), the fire relay O switches the power from pin 61 to pin 31 of the GKSh generator. A coded frequency signal enters the line. The display on the station duty board shows that the crossing is faulty. The station duty officer informs the alarm mechanic about the malfunction.

2.7 Algorithm for the operation of a guarded crossing

The algorithm was developed for a section of a railway with one-way traffic and a numerical code AB. An algorithm for the operation of a guarded crossing is presented in (Appendix 6). If there are no trains in the approaching sections, the crossing is open to vehicle traffic. At the moment the train enters the approach section, which is checked by operator 1, obstacle detection devices in the crossing area (OPA) are connected to the APS system, train movement parameters speed and, acceleration a and coordinate / are measured, and based on these parameters the distance Imin from the train to crossing, upon reaching which the crossing must be closed. These actions are performed by operators 2, 3 and 4. The last condition is checked by logical operator 5. When the train is at the point with coordinate Imin, a command is given to turn on the warning signal (operator 6), including red flashing lights at crossing traffic lights. Their proper operation is checked by operator 7. With a time delay t3 (operators 8 and 9), a command is given to close the barriers (operator 10). In typical APS systems, commands to operators 6 and 8 are received simultaneously. If the barrier is working properly (operator 11) and there is no obstacle to train movement in the crossing area (stuck vehicles, fallen cargo, etc.). After the barrier has lowered, the SPD is activated (operator 12). The crossing remains closed until the train passes through it, which is checked by operator 19. After the train has passed and in the absence of a second one in the approaching section (operator 20), the warning alarm is turned off, the barriers are opened and obstacle detection devices are turned off (operators 21, 22, 23, 24). The APS system returns to its original state. In cases where the warning alarm is damaged, the car barrier is not closed, or an obstacle is detected at the crossing, an emergency situation is created and measures must be taken to prevent a collision. The corresponding operators 7, 11 and 13 give a command to turn on the barrier signaling and encoding of track circuits (operators 14 and 15). The train slows down and stops on the approach section. After eliminating the damage or obstacle (operator 16), the barrier alarm is turned off and the encoding of the track circuit in the approach section is turned on. The train passes through the crossing, and the APS system returns to its original state. The algorithm for the operation of a crossing with an APS presupposes the presence of a one-way permanent signaling system in the direction of the highway. The alarm towards the railway is activated only in emergency situations.

Security questions:

What is the purpose of railroad crossings?
How are railroad crossings classified?
What devices are equipped with a controlled railway crossing?
What is an automatic barrier?
What additional safety devices are used at crossings?
What is the purpose of traffic lights?
How it is done automatic switching on and turning off fencing devices at crossings?
What are the functions of a railway crossing officer?

Karelin Denis Igorevich @ Orekhovo-Zuevsky Railway College named after V.I. Bondarenko - 2016

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”; 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. 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. Required condition 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 unhindered 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 seconds.

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.

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. 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 enough large number 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 actual speed approaching the train to the crossing and forming a command to close the crossing, taking into account this speed, as well as 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.

Automatic crossing alarm devices. Operating principle of the UZP (Crossing Barrier Device) When closing the crossing, the train must be located at a distance from it, which is called the estimated length of the approach section

What is APS

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