Types of automatic traffic signaling with barriers. Operation of automatic crossing signaling in the set odd direction of movement

Moving called the intersection at the same level of the railway with the road or urban transport lines. Crossings are a zone of increased danger for the movement of railway, road transport, as well as pedestrians. Equipping crossings with automatic crossing signaling devices (APS) and auto barriers increases the safety of transport operation.

Automatic crossing devices are widely used, which include automatic traffic signaling with or without automatic barriers and automatic notification signaling, which is supplemented by non-automated barriers.

APS devices are required to meet the following performance requirements:

the crossing signaling was switched on when the train entered the section of approach to the crossing for a time sufficient for the advance release of the crossing by road before the train approached the crossing, acted during the entire time the train was on the approach section and in the area of the crossing and turned off only after the train had completely vacated the crossing;

devices for automatic fencing of level crossings had a backup control, which is carried out by the person on duty at the level crossing;

from the side of the approach of trains, crossings are fenced off with normally off traffic lights with red lights, which are turned on by the duty officer for the crossing if necessary; it is allowed to use automatic blocking and electric interlocking traffic lights located near the crossing as barriers.

The use of certain automatic crossing devices is determined by its category. There are four categories of transfers.

Crossings of I and II categories, except for crossings with satisfactory visibility conditions for low-traffic sections and access roads, as well as III and IV categories in sections with a passenger train speed of more than 100 km / h, are equipped with automatic traffic signaling with automatic barriers. In other cases, automatic traffic signaling without barriers is used.

With automatic traffic lights the crossing is fenced with special crossing traffic lights with two red lights, which normally (there is no train) do not burn. Traffic lights are installed before the crossing on the right side of the movement of auto-drawn vehicles, their lights are directed towards the highway. When the train approaches the crossing, the lights of the crossing traffic lights begin to burn alternately with a flashing light. At the same time, an acoustic signal is activated, for which electric bells are installed at the crossing traffic lights.

With automatic traffic signaling with automatic barriers in addition to crossing traffic lights, a barrier is placed in each direction, the beam of which is normally in a vertical position. In the lowered (horizontal) position, the barrier beam is located at a height of 1 - 1.25 m from the road surface. The barrier beam is painted with red and white stripes. It has three electric lamps with red lights directed towards the highway and located at the base, in the middle and at the end of the beam, and the end lamp of the barrier is double-sided and continuously burns in the direction of the railway track in white. The rest of the lights flash in sync with the lights of the crossing traffic lights.

Alert signaling serves to give the duty officer on the crossing sound and light signals about the approach of the train. To do this, an alarm panel is installed at the crossing with warning lights for the approach of a train in an even or odd direction, as well as with lights for controlling lamps and electrical circuits of traffic lights; an electric bell for signaling the approach of a train, which is duplicated by a bell installed outside the premises of the crossing attendant; sealed button for turning on the barrage alarm.

Electric or mechanized barriers are used to protect crossings with warning alarms, which are controlled by the duty officer at the crossing. The normal position of such barriers is closed (except in some cases with particularly heavy traffic).

Barrage signaling at crossings, it is used to signal the train to stop in an emergency at the crossing. Only guarded crossings are equipped with barrage alarms. Special traffic lights and track blocking traffic lights or station traffic lights can be used as barriers if they are no more than 800 x away from the crossing where the crossing is visible. Special barrier traffic lights, as a rule, mast, with normally non-burning red lights, have a shape different from ordinary traffic lights.

Barrage traffic lights are installed on the right side of the train movement at a distance of 15 to 800 m from the crossing, ensuring the visibility of the traffic light at a distance not less than the braking distance of the train at its maximum speed and emergency braking. In sections with auto-blocking, barrier traffic lights are linked to the auto-blocking signals closest to the crossing, which overlap with a prohibitory indication with the ALS codes turned off when the barrier traffic lights are turned on. In sections without automatic blocking, if it is impossible to ensure the visibility of the stop traffic light and the stopping distance of the train, a warning traffic light of the same type is placed on which the yellow light turns on when the red light turns on at the stop traffic light.

The equipment and apparatus used only in crossing signaling includes crossing traffic lights, auto barriers and control panels for crossing signaling.

The appearance of a crossing traffic light with two signal heads and a "Beware of the train" sign in the form of a single cross is shown in Fig. 8.2. The visibility range of flashing lights of a crossing traffic light in clear sunny weather should be at least 215 m at a visibility angle of at least 70 °.

For crossings, vertically pivoting automatic (electric) barriers are designed, operating in automatic and non-automatic modes with a barrier bar length of 4 and 6 m (Fig. 8.3). The time of full opening (closing) of the barrier should not exceed 7-9 s.

Electric rail circuits are used to signal the approach of a train. In sections with auto-blocking, rail-mounted auto-blocking circuits are used. In areas without automatic blocking, depending on the type of traction and the reliability of the power supply, track circuits of direct or alternating current with a frequency of 50 or 25 Hz can be used. At crossings, rail circuits of overlaying a voice frequency of 1500-2000 Hz are used, which allow organizing a section of approach to the crossing, regardless of the arrangement of auto-blocking traffic lights and work with all types of traction. The maximum length of such a track circuit is 1500 m.

Crossing traffic lights and auto barriers are controlled according to the scheme (Fig. 8.5). When the train enters the section of approach to the crossing, one of the proximity detectors is de-energized state of emergency or NP in accordance with the direction of movement of the train and the power circuit of the switching relay is turned off AT.

After the end of the deceleration time to release the relay AT its repeater is de-energized PV, the contacts of which turn off the power supply circuit of the control relay At and relay VM(not shown in the diagram) and the power supply circuit of the bells of the auto barriers is turned on. The bells will be turned on until the barrier bar is completely lowered, when their power circuit is opened by the autoswitch contacts.

relay contacts At the lamps of crossing traffic lights and the lamps on the bars of auto barriers are switched on. Relay Y/(connected in series with relay U) includes a flashing light circuit containing a pendulum transmitter and a relay M, thanks to which the lamps of crossing traffic lights 1L and 2.77 and lamps on the bars of barriers 1LSH and 2LSH start flashing. Lamp ZLSh at the end of the beam burns continuously.

Relay VM has a release time of approximately 14-16 s, which is necessary for the car that entered the crossing at the moment the alarms were turned on to have time to release it. After lowering the armature of the relay VM barrier closing relay is energized zsh and the barrier opening relay is de-energized OSH. relay contacts zsh the circuit of the armature and the excitation winding of the barrier drive motor is closed, and a current of such polarity is supplied to the excitation winding, which ensures the lowering of the bar. The motor is switched off by the autoswitch contacts of the barrier when the beam reaches the horizontal position.

After the train passes through the crossing, the corresponding relay is energized state of emergency or NP and a circuit is created to excite the relay CT, which has a delay in closing the front contact of about 8-16 s, achieved by the presence of a thermoelement. Relay switching circuit AT and /<Т построена таким образом, что возбуждение реле AT only possible with a time delay. This excludes the opening of the crossing in the event of a short-term loss of the shunt on the track circuit of the approach section. When the relay is energized AT the thermocouple is switched off, and the relay AT and CT self-blocking through its front contacts.

After the relay has been energized AT relay power circuits are switched on PV, VM. This de-energizes the relay. zsh and the relay is energized osh, switching the polarity of the power supply of the motor excitation winding with its contacts. When the barrier bar takes a vertical position, the autoswitch contacts turn off the engine, gets under the current of the relay U, which turns off the signal lights of the crossing traffic light and the barrier.

The control of the crossing signaling does not differ from the control of the auto barriers from the control panel, but in this case, using the buttons 3 (closing) and O(opening) action is carried out directly on the relay PV.

To temporarily hold the barrier beam in a vertical position, the duty officer must press the button B on the shield, which turns off the power circuit of the relay ZSH. Relay contact 3 in this circuit excludes the opening of the barrier by the button B. Relay AS and BS turn on the armature chains of the motors when the barrier beam is raised or lowered. Double winding relays JSC and IN control the serviceability of lamps of crossing traffic lights in the on and off states. The lights at the traffic lights are lit by the ZS button, which, when pressed, de-energizes, the relay ZG, which turns on the rear contacts of the lamp of obstruction traffic lights.

Crossing signaling devices and auto barriers are powered from the AC network through VAK-13M type rectifiers connected according to the continuous recharge circuit with a battery used for backup power. Signal lamps are powered by an alternating current signal transformer, the presence of which is controlled by an alarm relay. When the AC power is turned off, the alarm relay de-energizes and switches the power of the lamps to the battery.

Radio relay communication.

Radio relay communication systems(PPC) have also found wide application in terrestrial radiotelephony and, in particular, in radio communications in railway transport. The stages of development of RRS on railways can be traced by the example of the construction and operation of a radio relay line on the route of the Great Moscow Ring Road, the length of which is 420 km.

RRL is a chain of transceiver stations (terminal, intermediate, nodal) installed at a line-of-sight distance (40 - 70 km in the frequency ranges up to 6 - 8 GHz and several km in the 30 - 50 GHz ranges) with an antenna height of 60-100 m ).

Terminal stations are installed at the extreme points of the communication line and contain modulators and transmitters in the signal transmission direction and receivers with demodulators in the receive direction. For reception and transmission, one antenna is used, connected to the reception and transmission paths using an antenna splitter (duplexer), or two antennas.

Modulation and demodulation of signals is carried out at one of the standard intermediate frequencies (70 - 1000 MHz). At the same time, modems can work with transceivers using different frequency ranges. Transmitters are designed to convert intermediate frequency signals into the operating range of the microwave, and receivers are designed to inversely convert and amplify intermediate frequency signals.

There are RRL systems with direct modulation of microwave (microwave) signals, but they are of limited distribution.

RRL classification

Two types of RRL: line of sight and tropospheric.

By appointment: long-distance trunk, intrazonal, local RRL.

By frequency range: frequency bands are allocated in the region of 2, 4, 6, 8, 11 and 13 GHz. Research is underway to create RRL at frequencies of 18 GHz and higher. But at HF, the signal is greatly attenuated in precipitation.

According to the method of compression and the type of modulation: with FDM, with TDM and analog pulse modulation, digital RRL.

In terms of throughput: RRL of large capacity - (more than 100 Mbps), medium capacity for zonal communication - 60 ... 300 k. (10-100 Mbps), small capacity for local and departmental communications. Multiple shafts are used to increase throughput.

Radio relay lines on the railway provide the organization of trunk, road and departmental communications. An exemplary scheme of a railway radio relay line provides for 3 radio channels. Intermediate points of the main and road trunks are located at a distance of 30 - 50 km, while industrial points with the allocation of channels are built near railway stations, where there are departments and road departments, as well as junctions and large stations. Industrial centers with the allocation of channels of the departmental trunk are located at all railway stations at a distance of 5 to 25 km. Various types of signals can be transmitted over a communication channel: telephone (conversation), sound or television broadcasting, telegraph, telecontrol, etc.

Separation equipment in combination with RRL microwave transmitting and receiving equipment forms a broadband path, or communication trunk, through which the group signal generated in the separation equipment is transmitted. On RRL, to increase their economic efficiency and throughput, several parallel radio channels are organized, equipped with the same type of receiving and transmitting radio equipment. The equipment of adjacent trunks operates at different carrier frequencies, but on common antennas. Connect it to the antenna-feeder system through separation filters (they are not shown in Fig. 22.2). On modern lines, up to six to eight trunks or more are organized, used for multi-channel telephony, television, redundancy, etc. The capacity of the telephone trunk is selected from 24 to 1920 channels

On the RRL shown in Fig. 22.2, for the transmission of multichannel telephony signals, telephone trunks with a capacity of 60 channels each are organized. Television programs (video signal and audio signals) are transmitted in a special television trunk ///. In this case, the video signal (image) and the audio signal can be transmitted together in one television trunk or separately when the audio signal is transmitted in one of the telephone trunks.

The main equipment of radio relay stations includes receiving and transmitting radio equipment (operating in the microwave range), antenna-feeder devices, separation equipment, power supply devices, to accessories- devices for service communication, telecontrol, telesignaling, control and measurements.

The equipment of radio relay stations is installed in a technical building, and the antennas are installed on masts or towers. The height of the antenna suspension should provide a direct line of sight between them. Depending on the terrain, the height of masts or towers reaches 80 m or more. To reduce the length of high-frequency feeders between the radio equipment and the antenna, the receiving-transmitting equipment is placed in the upper floor of a monolithic reinforced concrete tower, and antenna devices are placed on its roof. Power equipment is being installed in the lower floors of the tower.

The principle of operation of the UZP (Device barrier moving)

The barrier device works as follows: when the drive motor is turned on, the drive lock first falls off, which held the cover in the lowered position, then, under the influence of the counterweight and the drive gate, the cover of the ultrasonic device rises to an angle of 30; at the end of the lid up phase, the autoswitch is activated and the motor is switched off, preparing the power circuit for the motor to be switched back on. Protective devices, as well as auto barriers, have dual control - automatic and non-automatic - by pressing the buttons on the APS shield. In both cases: turning on the signal lights, moving the barrier bars to horizontal (when closing) and vertical (when opening), the covers of the UZ to the raised (blocking) - lowered (allowing passage) positions are carried out by de-energizing and, accordingly, excitation of 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 at the section approaching the crossing, the PV relay is de-energized in the crossing signaling relay cabinet, the PV1 relay is energized, the red flashing lights of the crossing traffic lights are turned on, the system for monitoring the vacancy of the zones of the covers of the UZ turns on, and after about 13 s the relay VM 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 switch-on relay) is turned on, after about 3 s, the BVMSH holding unit is activated, the relay for lifting the covers of the protective UZ, UP and VUZM is energized. The friction relay F and the NPS relay are triggered, the contacts of which control the UZ drives. The operation of the PPS relay of each of the drives is possible provided that the zones of the covers of the ultrasonic device are free. The control of the vacancy of the zones of the covers of the ultrasonic device is carried out by the front contacts of the RZK relay, which receives power from the KPC sensor. RN relays control the presence of voltage from the control outputs of the KPC sensors. After the PPS and LPS relays are activated, power is supplied to the electric motors of the drives, within 4 s the covers of the UZ occupy a blocking position that prevents vehicles from entering the crossing. Switching off the electric motors of the drives after lifting the covers of the ultrasonic device is carried out by the working contacts of the autoswitch. In the case of operation of the electric motors of the drives for friction (the UZ covers cannot be raised or lowered due to the presence of an obstacle), the NPS relay and the electric motors are turned off by the contacts of the friction relay F, which has a delay of 6-8 s. After the PPS and LPS relays are activated, power is supplied to the electric motors of the drives, within 4 s the covers of the UZ occupy a blocking position that prevents vehicles from entering the crossing. Switching off the electric motors of the drives after lifting the covers of the ultrasonic device is carried out by the working contacts of the autoswitch. In the case of operation of the electric motors of the drives for friction (the UZ covers cannot be raised or lowered due to the presence of an obstacle), the NPS relay and the electric motors are turned off by the contacts of the friction relay F, which has a delay of 6-8 s. The drive motors are powered by a rectifier (BP) (VUS-1.3). In the event of failure of the main rectifier BP 1, relay contacts A2 switch to the backup rectifier BP 2 (VUS-1.3). After the train passes the crossing, the PV relay is energized in the APS relay cabinet and switches off the VUZ relay in the UZP relay cabinet. The electric motors of the drives begin to work to lower the covers of the ultrasonic device. After the covers are lowered, the relays 1PK - 4PK are energized. With the control of the excitation of the relay 1PK - 4PK, the circuit of the U1, U2 relays in the APS relay cabinet, which also controls the rise of the barrier bars, is closed, and the red flashing lights of the crossing traffic lights are turned off. The shift attendant also has the opportunity to bring the covers of the UZ into a blocking position or lower them. In the first case, he needs to press the “close” button on the APS panel: in the APS cabinet, the PV relay is de-energized, the crossing signaling devices are turned on, and in the UZP relay cabinet, the VUZ relay is activated after 13 s and, as in the case of automatic notification of the approach of a train , the UZ covers are lifted. Pull this button out to lower the covers. For emergency lowering of the UZ covers, it is necessary to break the seal on the UZP shield from the button with the “normalization” fixation and press it. The covers of all USPs are lowered, and the USP is switched off from operation. However, in this case, switching off the flashing of the red lamps of crossing traffic lights is carried out without controlling the lowering of the covers of the ultrasonic device. Also, the decision was made to prevent flashing of the red lamps of crossing traffic lights after pressing the “normalization” button in case of loss of control over the position of the covers of the ultrasonic device on the contacts of the autoswitches of the ultrasonic drives. When pressing the “normalization” button, the duty officer on the crossing must make sure that the covers of the UZ are lowered and, if any cover has not taken the lower position, finish the operation of the drive using the kurbel handle. Three rows of light bulbs (light-emitting diodes) with 4 light bulbs (light-emitting diodes) in a row are provided on the UZP shield to control the positions of the covers and the state of the KPC sensors. The upper 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 the relay 1PK-4PK - about the lower position of the covers, and the lower row, with steady burning, signals the good condition of the KPC sensors, and by blinking signals a sensor malfunction. In the absence of a train in the approach section, the lower row of light bulbs (LEDs) does not light up. Three buttons are installed on the UZP panel: - two buttons without fixation, not sealed, "exit 1" and "exit 3" - for lowering the covers of the first and third UZ, respectively, at the exit of vehicles from the crossing; - button with fixation, sealed, "normalization" - for lowering the covers of the ultrasonic device and turning off the ultrasonic device from operation in case of a malfunction. The control of the not pressed position of the “normalization” button on the shield of the UZP is carried out by the burning of the light bulb (LED) “normalization”.

Crossing alarm. General information

Crossings of railroad tracks on the same level as roads, tramways and trolleybus lines are called railroad crossings. For traffic safety, crossings are equipped with guarding devices. On the side of trackless transport, automatic traffic signaling, automatic barriers and half-barriers, non-automatic barriers with a manual mechanical or electric drive, together with an alert (automatic or non-automatic) signaling, are used as typical fencing devices.

With automatic traffic 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 of the movement of trackless transport. Red lights of traffic lights are directed towards the road; they normally do not light up, indicating the absence of trains on the approaches to the crossing, and allow auto-drawn vehicles to move through the crossing. When the train approaches the crossing, the lights of the crossing traffic lights begin to blink alternately, and the bells ring at the same time. From now on, the movement of auto-drawn vehicles through the crossing is prohibited. After the train passes through the crossing, the traffic lights go out, the bells are turned off and the movement of trackless vehicles through the crossing is allowed.

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

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

Automatic half-barriers, in addition to devices that ensure their automatic operation when trains are in motion, 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 duty officer at the crossing, located at the shield, can clearly see the approach paths of trains and cars.

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

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

In case of damage to the automatic control system, the half-barrier remains in the blocking position. If there are no trains on the way, the crossing attendant can let vehicles through the crossing. To do this, he presses the button Opening the barrier. The half-barrier beam rises to a vertical position and the red lights on the traffic light and the beam will 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 duty officer at the crossing are used as fencing means. Automatic or non-automatic light and sound warning signaling is used to notify the duty officer on the crossing.

To signal the train to stop in the event of an emergency at the crossing, a barrage alarm is used. As barrier signals, special barrier traffic lights, automatic and semi-automatic blocking traffic lights and station traffic lights are used, if they are no more than 800 m away from the crossing and the crossing is visible from the place of their installation. Barrier traffic lights, as a rule, are mast; they are shaped differently from conventional traffic lights. The red lights of the traffic lights do not light normally. They are turned on by the crossing attendant by pressing the Turn off the traffic lights on the panel. By returning (pulling out) the button to its normal position, the traffic lights are turned off. At the same time, the bulbs on the panel light up, which control the correct operation of the barrier traffic lights. If the control lamp does not light up when the obstruction signal is turned on, this means that the traffic light is faulty and the crossing duty officer must take additional measures to protect the crossing from the side of the faulty traffic light.

In areas equipped with automatic blocking, when the barrage signaling is turned on at the automatic blocking signals closest to the crossing, their indication switches to prohibiting and the supply of ALS codes to the track circuits before the crossing stops.

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

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

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

Category III - intersections with roads that do not fit the characteristics of crossings of categories I and II, and if the intensity of traffic on the crossing with satisfactory visibility exceeds 10,000 train-crews, and with unsatisfactory (poor) - 1000 train-crews per day. Visibility is considered satisfactory if from the crew, located 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 the crossing is measured in train-crews, i.e., the product of the number of trains and the number of crews passing through the crossing per day.

To automatically turn on the guards when the train approaches the crossing, approach sections equipped with track circuits are arranged. The length of the approach section depends on the time of notification, 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 the vehicle through the crossing (assumed 5 km/h), the length of the vehicle (assumed 6 m) and the time of lowering the barrier bar (10 s) if the latter blocks the entire carriageway.

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

The automatic crossing signaling devices mainly use the same equipment and apparatus that is used in other railway automation devices. Special equipment includes crossing traffic lights, electric barriers and control panels for crossing signaling. 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 zone of the signal indications.

Use electric barriers of vertically rotary type (fig. 141). It consists of a barrier bar 1, a cross-shaped signal sign 2 with glass reflectors, two unambiguous heads 3, an electric bell 4, a mast 5 fixed to the body of the electric drive with four bolts, an electric drive 6 and a foundation 7.

The barrier bar of the semi-barrier, 4 m long, is completely balanced by the weights and is transferred from the closed position to the open position and back by the electric motor. During a power outage, manual translation of the timber is provided. To prevent breakage of the beam when it is hit by vehicles, it is fixed in a horizontal position not rigidly, but with two ball latches on the barrier frame and can be rotated about its vertical axis by 45°. In the raised state, the beam is locked by a transfer mechanism.

The electric drive of the barrier consists of a cast iron housing, in which a DC electric motor with a power of 95 W for a voltage of 24 V with 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 with the shaft drive, which close the contacts at different angles of the barrage rise. A two-arm damping device lever is connected to the drive shaft. The drive mechanism is equipped with a friction device that protects the electric motor from overloads.

At the intersection of the railway, on the same level with the roads, crossings are arranged. They can be adjustable, i.e. equipped with crossing signaling devices, and unregulated, when the possibility of safe passage depends entirely on the driver of the vehicle.

In some cases, the crossing signaling is serviced by a duty worker. Such crossings are called guarded, and unattended - unguarded.

Crossing devices include automatic traffic signaling, automatic barriers, electric barriers and mechanized barriers. These devices serve to stop the movement of vehicles through the crossing when a train approaches it.

Crossings with heavy traffic for fencing from the side of the highway are equipped with automatic traffic light crossing signaling with automatic barriers. The crossing is fenced with PS crossing traffic lights with two alternately flashing red lights, and an audible signal is given to alert pedestrians.

Flashing signaling is used to ensure that the driver of the vehicle could not take the crossing for a regular urban intersection.

To warn vehicles about approaching the crossing, two warning signs are installed in front of it - at a distance of 40 ... 50 and 120 ... 150 m from the substation.

Automatic barriers blocking the carriageway of the road, and traffic lights of automatic traffic signaling are installed on its right side.

The normal position of automatic barriers is open, and that of electric barriers and mechanized barriers is usually closed. To activate the automatic crossing signaling, auto-blocking rail circuits or special circuits are used.

When the train approaches a certain distance to the crossing, the crossing light signaling and the bell are turned on, after 10 ... 12 s the barrier bar is lowered and the bell is turned off, and the light signaling continues to operate until the crossing is cleared and the bar is raised.

In the event of an accident at the crossing, it is protected from the side of the approach of trains with red lights of traffic lights, switched on by the duty officer at the crossing.

In sections with auto-lock, the red lights of the nearest auto-lock traffic lights light up at the same time.

Barrage traffic lights are installed on the right side along the course of the train at a distance of at least 15 m from the crossing. The location of the traffic light is chosen so that the visibility of the traffic light is ensured at a distance not less than the braking distance required in this case for emergency braking and the maximum possible speed.

At railway crossings, trains have the priority right to move freely through the crossing.

In order to avoid closing the auto-blocking rail circuits when caterpillar tractors, rollers and other road vehicles pass through the crossing, the top of the crossing flooring is arranged 30 ... 40 mm higher than the rail heads.

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Crossing signaling devices

Bibliographic list

1. Classification of crossings and fencing devices

Railway crossings are the intersection of roads with railway tracks at the same level. movingconsideredobjectselevateddanger. The main condition for ensuring traffic safety is the condition: rail transport has an advantage in traffic over all other modes of transport.

Depending on the intensity of traffic of railway and road transport, as well as depending on the category of roads, crossings are divided into fourcategories. Crossings with the highest traffic intensity are assigned the 1st category. In addition, category 1 includes all crossings on sections with train speeds over 140 km/h.

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

The list of crossings serviced by an employee on duty is given in the Instructions for the operation of railway crossings of the Ministry of Railways of Russia. Previously, such crossings were briefly called - "guarded crossings"; according to the new Instruction and in this work - "crossings with an attendant" or "serviced crossings".

Crossing signaling systems can be divided into non-automatic, semi-automatic and automatic. In any case, a crossing equipped with a crossing signaling is fenced with crossing traffic lights, and a crossing with an attendant is additionally equipped with automatic, electric, mechanized or manual (horizontally swivel) barriers. On themovingtraffic lights horizontally there are two lamps of red light, 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 individual crossings without an attendant, red lights are supplemented white moonfire. The white-moon fire at an open crossing burns in a flashing mode, indicating the serviceability of the APS devices; when closed, it does not light up. When the white-lunar fire is extinguished and the red ones are not burning, drivers of vehicles must personally verify that there are no approaching trains.

On the railways of Russia, the following typescrossingsignaling:

1 . traffic lightsignaling. It is installed at crossings of access and other ways, where approach sections cannot be equipped with track 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 a person on duty, the crossing traffic lights are switched on when the button on the crossing signaling board is pressed. After that, at the shunting traffic light, the red 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 unattended crossings, crossing traffic lights are complemented by a white-moon flashing light. The crossing is closed by employees of the drafting or locomotive crew using a column installed on the mast of the shunting traffic light or automatically using track sensors.

2 . Automatictraffic lightsignaling.

At unattended crossings located on hauls and stations, the control of crossing traffic lights is carried out automatically under the action of a passing train. Under certain conditions, for crossings located on the stage, crossing traffic lights are supplemented with a white-moon flashing light.

If station traffic lights are included in the approach section, then their opening occurs with a time delay after the crossing is closed, providing the required notification time.

3 . Automatictraffic lightsignalingwithsemi-automaticbarriers. Used on serviced crossings at stations. The crossing is closed automatically when the train approaches, when the route is set at the station if the corresponding traffic light enters the approach section, or forcibly when the station attendant presses the "Closing the crossing" button. The lifting of the bars of the barriers and the opening of the crossing is carried out by the person on duty at the crossing.

4 . Automatictraffic lightsignalingwithautomaticbarriers. It is used on serviced level crossings. Crossing traffic lights and barriers are controlled automatically.

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

2. Calculation of the approach area

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

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

where t 1 - the time required for the car to pass the crossing;

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

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

Time t 1 is determined by the formula

, with,

where ? n - the length of the crossing, equal to the distance from the crossing traffic light to a point located 2.5 m from the opposite extreme rail;

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

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

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

The notification time is taken at least 40 s.

When closing the crossing, the train must be at a distance from it, which is called estimatedlongsiteapproximation

L p = 0.28 V max t cm,

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

The approach of the train to the crossing in the presence of AB is fixed using the existing auto-blocking RC or with the help of overlay track circuits. In the absence of AB, sections of approach to 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 in one approach section (see Fig. 1, odd direction), in the second - in two (see Fig. 7.1, even direction).

Rice. 1 Plotsapproximationtomoving

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

Essential operational disadvantage of all existing systems of automatic crossing signaling (AP) is fixedlengthsiteapproximation, calculated based on the maximum speed on the section of the fastest train. On a sufficiently large number of sections, the maximum speed limit for passenger trains is 120 and 140 km/h. In real conditions, all trains run at a slower speed. Therefore, in the vast majority of cases, the crossing closes prematurely. Excessive time of the closed state of the crossing can reach 5 minutes. This causes a delay of vehicles at the crossing. In addition, drivers of vehicles have doubts about the serviceability of the crossing signaling, and they can start moving when the crossing is closed.

This disadvantage 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 have been proposed. However, they did not find practical application.

Otherdisadvantage AP systems is an imperfect security procedure atemergencysituationson themoving ( a stopped car, a collapsed load, etc.). At crossings without a duty officer, traffic safety in such a situation depends on the driver. At serviced crossings, the duty officer must turn on the barrier traffic lights. To do this, he needs to turn his attention to the current situation, assess it, approach the control panel and press the appropriate button. It is obvious that in both cases there is no efficiency and reliability of detecting an obstacle to the movement of the train and taking the necessary measures. To solve this problem, work is underway to create devices for detecting obstacles at the crossing 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, the existing developments are not yet technically perfect and their implementation is not economically feasible.

3. Structural diagram of automatic crossing signaling

Automatic crossing signaling (AP) schemes differ depending on the area of application (segment 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 (attended or unattended) and a number of other factors. As an example, consider the block diagram of the AP on a double-track section equipped with a CAB, with notification in an even direction for two approach sections (Fig. 7.2).

In any case, the general scheme of the AP consists of schememanagement, which controls the approach, the correct passage of the train and the release of the crossing, and schemeinclusion, which includes crossing devices and controls their condition and serviceability.

The approach of the train is fixed using the existing track chains AB. When the head of the train enters the BU 8P, the notification transmitter PI transmits information about this through the notification chain I-OI to the notification receiver At 6th signal installation. With 6SU, this information is transmitted to the crossing.

When a notification is received, the time delay block BB generates a command to close the crossing "Z" after a time that compensates for the difference between the calculated and actual lengths of the approach section. During the movement of the train, the crossing remains closed due to the employment of RC 6P.

Rice. 2 Structuralschemeautomaticenclosingdeviceson themoving

The 6P rail circuit is distinguished before the move by installing insulating joints. The release of the crossing is fixed by the control circuit of the release of the crossing KOP upon the release of this RC. At the same time, the actual passage of the train is checked to exclude a false opening of the crossing when applying and removing an extraneous shunt at RC 6P.

Short term shunt loss control circuit KPSh generates the "O" command 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 during the movement of the train along RTs 6P).

Broadcast scheme SHT ensures the normal operation of AB and ALS, broadcasting the signal current from the 6Pa track circuit to the 6P track circuit.

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

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

In the system of automatic traffic signaling with automatic barriers ( APS) crossing traffic lights (two red lights) and a bell are complemented by auto barriers, which are an additional means of fencing the crossing. The electric motors of the barriers are activated 13…15 s after the closing of the crossing, which prevents the beam from being lowered onto vehicles. After lowering the beam, the bell is turned off. In operating devices, DC electric motors are used. At present, new automatic barriers of the PASH1 type are being 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;

· The lowering of the barrier beam occurs under the action of its own weight, which increases the safety of train traffic in case of circuit malfunctions or power failure.

In APSH systems, when the crossing is cleared by a train, the barrier bars automatically rise to a vertical position, after which the red lights at 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 duty officer on the crossing presses the "Open" button.

In areas with heavy traffic of trains and vehicles, they begin to additionally install devicesbarriersmovingtypeUSP. This device is a metal strip, which is located across the road, normally lies in the plane of the roadbed and does not interfere with the movement of vehicles. After the barrier beam is lowered, the edge of the strip facing the direction of vehicles rises to a certain angle. This excludes the entry to the crossing of a car that has lost control or is driven by an inattentive driver. To exclude the possibility of SPD operation under the vehicle or directly in front of it, ultrasonic sensors are used to control the vacancy of the SPD location zone. For manual control of the SPD and monitoring the status and serviceability of these devices, a control panel with the necessary control buttons and display elements is provided.

At crossings equipped with the APS system, the use of barragetraffic lights to transmit information to the driver about an emergency at the crossing. 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 crossing is visible to the driver from the place of their installation. Otherwise, special normally non-burning obstruction traffic lights are installed (see Fig. 2, traffic light Z2). The red light at the barrier traffic lights is turned on by the duty officer at the crossing in case of situations that threaten the safety of train traffic. In addition to the closing of the barrier traffic lights, the transmission of ALS code signals to the distribution center before the crossing is stopped and the crossing is closed.

To be able to control barrier traffic lights and forced manual control of crossing devices, a shieldmanagement. Buttons are provided on it: closing the crossing, opening the crossing, maintaining (holds the bars of the barriers from lowering when the crossing is closed), turning on the traffic lights. On the same panel, an indication is provided:

Approaching trains indicating the direction and route;

condition and serviceability of crossing and barrier traffic lights. When the traffic lights are off, the green lights are on; when the prohibition indication is turned on, the red indicator lights of the corresponding traffic light light up. If the traffic light bulbs fail, the corresponding green or red indicator light starts flashing;

state and serviceability of the flashing circuit;

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

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

4. Features of AP in two-way traffic

With two-way train traffic, the crossing should be automatically closed when a train of any direction approaches, regardless of the direction of the AB. This requirement is due to the fact that the direction change circuits are not stable enough. Therefore, in the event of a failure of their work, it is provided for the departure of trains in an unspecified direction by order without using the means of automatic control of train 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 of movement.

3. Organization of control of 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 is released by the train of the established direction and enters the section of the approach of trains of the unknown direction.

5. Cancellation of this lock after a certain time.

6. Exclusion of the open state of the crossing when the utility train returns after it has stopped behind the crossing.

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

In accordance with new technical solutions " Schemecrossingsignalingformoving,locatedon thehaulsatanymeanssignalingandconnections (APS-93)" AP schemes were simplified and unified for use with any type of AB or without AB both on single-track and double-track sections. These technical solutions provide for the use of existing tonal auto-blocking RCs (see clause 2.4 and section 5), the use of SECs in the form of overlay track circuits on the track circuits of traditional AB systems, or equipping approach areas with tonal RCs in the absence of AB.

Application tonalRC in AP schemes allowed:

crossing automatic signaling

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

2. Ensure the length of the approach section is equal to the calculated length and exclude the explosive scheme.

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

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

5. Increase the reliability of control over the actual passage of the train.

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

Control questions and tasks

1. What kind of crossings are called regulated?

2. Find the difference in the operation of the crossing signaling systems of the "Traffic signaling" and "Automatic traffic signaling" types.

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

4. Think about why the APS system is used only at crossings with an attendant?

5. What is the disadvantage of systems with a fixed length of the approach segment? 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 PASH1 barriers.

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

Bibliographic list

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

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

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

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

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

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

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

8. Kazakov A.A. and other Systems of interval regulation of train traffic. - M.: transport, 1986.

9. Kazakov A.A. etc. Auto-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. Equipment of railway automation and telemechanics: Handbook: in 2 books. Book 1. - M.: NPF "Planet", 2000.

12. Soroko V.I., Rozenberg E.N. Equipment of railway automation and telemechanics: Handbook: in 2 books. Book 2. - M.: NPF "Planet", 2000.

13. Dmitriev V.S., Minin V.A. Auto-blocking systems with tone frequency rail circuits. - M.: Transport, 1992.

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

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

16. Bryleev A.M. etc. Automatic locomotive signaling and autoregulation. - 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. Auto-blocking with tone-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 for railway transport I-206-91. - L.: Giprotranssignalvyaz, 1992.

20. Auto-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 for railway transport I-223-93. - L.: Giprotranssignalvyaz, 1993.

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

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

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