Types of automatic traffic light signaling with barriers. Crossing signaling devices. Railway crossings are the intersection of highways and railway tracks at the same level. Crossings are considered high-risk objects
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 alarm 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 it stops pulse work relay 2I, 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.
Moving called an intersection at one level railway with automobile or urban transport lines. Crossings are an area of increased danger for the movement of railway, road transport, and pedestrians. Equipping crossings with automatic crossing signaling devices (APS) and auto barriers increases the safety of transport operations.
Devices for automatic fencing of crossings have become widespread, which include automatic traffic light alarms with or without automatic barriers and automatic warning alarms, which are supplemented by manual barriers
It is necessary that APS devices meet the following operational requirements:
The crossing alarm was switched on when the train entered the section approaching the crossing for a time sufficient for the advance clearing of the crossing by road transport before the train approached the crossing, was in effect for the entire time the train was in the approach section and in the crossing area and was turned off only after the train had completely cleared the crossing;
automatic crossing fencing devices had backup control, which is carried out by the crossing duty officer;
on the approach side of trains, crossings are fenced off by normally switched off traffic lights with red lights, which are turned on by the crossing duty officer if necessary; It is allowed to use automatic blocking and electrical interlocking traffic lights located near the crossing as barrier traffic lights.
The use of certain devices for automatic crossing fencing is determined by its category. There are four categories of moves.
Crossings of categories I and II, except for crossings with satisfactory visibility conditions for low-traffic areas and access roads, as well as categories III and IV in areas with passenger train speeds of more than 100 km/h, are equipped with automatic traffic lights with auto barriers. In other cases, automatic traffic light signaling without barriers is used.
With automatic traffic light signaling The crossing is protected by special crossing traffic lights with two red lights, which normally (there is no train) do not light up. Traffic lights are installed before crossings right side on the movement of horse-drawn vehicles vehicles, their lights are directed towards highway. As the train approaches the crossing, the crossing traffic lights begin to flash alternately. At the same time, an acoustic signal is activated, for which electric bells are installed at crossing traffic lights.
With automatic traffic light signaling with automatic barriers In addition to crossing traffic lights, a barrier is placed in each direction, the beam of which is normally located in 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 lantern with red lights directed towards the road and located at the base, in the middle and at the end of the beam, and the end light of the barrier is double-sided and continuously lights up towards the railway track in white. The remaining lights flash synchronously with the crossing traffic lights.
Warning alarm serves to provide the crossing duty officer with sound and light signals about the approach of a train. To do this, an alarm panel is installed at the crossing with warning lights about the approach of a train in an even or odd direction, as well as with control lights for lamps and electrical circuits of traffic lights; an electric bell alerting about the approach of a train, which is duplicated by a bell installed outside the premises of the crossing duty officer; sealed button for turning on the security alarm.
For fencing crossings warning alarm use electric or mechanized barriers, which are controlled by the crossing attendant. The normal position of such barriers is closed (except in certain cases with particularly heavy traffic).
Barrage alarm at crossings it is used to give the train a signal to stop at emergency situation on the move. Only guarded crossings are equipped with barrier alarms. Special traffic lights and track blocking traffic lights or station traffic lights can be used as barrier lights if they are no more than 800 away from the crossing, and the crossing is visible from the place where they are installed. Special obstruction traffic lights, usually mast-mounted, with normally unlit red lights, have a different shape from ordinary traffic lights.
Barrier traffic lights are installed on the right side along the movement of the train 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 when it is moving. maximum speed and emergency braking. In areas with automatic blocking, barrier traffic lights are linked to the automatic blocking signals closest to the crossing, which overlap with a prohibiting indication with the ALS codes turned off when the barrier traffic lights are turned on. In areas without automatic blocking, if it is impossible to ensure visibility of the barrier traffic light, within the distance of the train braking distance, a warning traffic light of the same type is placed, on which a yellow light is turned on when the red light is turned on at the barrier traffic light.
Equipment and equipment used only in crossing signaling include crossing traffic lights, auto barriers and crossing alarm control panels.
Appearance 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 the flashing lights of a crossing traffic light in clear sunny weather should be at least 215 m with a visibility angle of at least 70°.
Vertical-rotating automatic (electric) barriers are designed for crossings, operating in automatic and non-automatic modes with a barrier beam length of 4 and 6 m (Fig. 8.3). The time for complete opening (closing) of the barrier should not exceed 7-9 s.
Electric track circuits are used to notify trains when they are approaching. In areas with automatic blocking, automatic blocking rail chains are used. In areas without automatic blocking, depending on the type of traction and reliability of power supply, rail circuits of constant or AC frequency 50 or 25 Hz. At crossings, rail circuits superimposing a tonal frequency of 1500-2000 Hz are used, which allow organizing the approach to the crossing regardless of the placement of automatic blocking traffic lights and work with all types of traction. Maximum length such a rail chain is 1500 m.
Crossing traffic lights and auto barriers are controlled according to the scheme (Fig. 8.5). When a train enters the section approaching the crossing, one of the approach detectors is de-energized Emergency or NP in accordance with the direction of movement of the train and the power circuit of the turning on relay is turned off IN.
After the deceleration time has expired, the relay releases IN its repeater is de-energized PV, the contacts of which turn off the power circuit of the control relay U and relay VM(not shown in the diagram) and the power supply circuit for 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 U the lamps of crossing traffic lights and the lamps on the bars of car barriers are turned on. Relay U/(connected in series with relay U) includes a flashing light circuit containing a pendulum transmitter and relay M, thanks to which the lamps of crossing traffic lights 1L and 2.77 and lamps on the barriers bars 1LSh And 2LSH start flashing. Lamp ZLSH at the end of the beam it burns continuously.
Relay VM has a release time of approximately 14-16 s, which is necessary so that a car entering the crossing at the moment the alarms are turned on has time to release it. After lowering the armature, the relay VM The barrier closing relay is excited 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 that ensures the lowering of the beam. The engine is turned off by the barrier autoswitch contacts when the beam reaches a horizontal position.
After the train passes through the crossing, the corresponding relay is excited 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 connection diagram IN And /<Т построена таким образом, что возбуждение реле IN only possible with a time delay. This prevents the crossing from opening in the event of a short-term loss of the shunt on the track circuit of the approach section. When the relay is energized IN The thermocouple turns off and the relay IN And CT self-blocking through its front contacts.
After energizing the relay IN relay power circuits turn on PV, VM. This de-energizes the relay ZSH and the relay is excited OSH, switching the polarity of the motor excitation winding power supply with its contacts. When the barrier beam takes a vertical position, the autoswitch contacts turn off the engine and the relay is energized Uh, which turns off the signal lights of crossing traffic lights and barriers.
Controlling a crossing alarm is no different from controlling auto barriers from the control panel, but in this case using buttons 3 (closing) and ABOUT(opening) the effect is carried out directly on the relay PV.
To temporarily hold the barrier beam in a vertical position, the attendant must press the button B on the panel, which turns off the relay power circuit ZSH. Relay contact 3 in this circuit prevents the barrier from opening with a pushbutton B. Relay AS And BS turn on the motor armature chains when raising or lowering the barrier beam. Double winding relays JSC And IN monitor the serviceability of crossing traffic light lamps in the on and off states. The lights at obstruction traffic lights are lit by the ZS button, when pressed the relay is de-energized ZG, which turns on the rear contacts of the traffic light lamps.
Devices crossing alarm and auto barriers are powered from an alternating current network through rectifiers of the VAK-13M type, connected according to a continuous charging circuit with a rechargeable battery used for backup power. The signal lamps are powered by an alternating current from the signal transformer, the presence of which is controlled by an alarm relay. When the AC power is turned off, the emergency relay de-energizes and switches power to the lamps to the battery.
Radio relay communication.
Radio relay communication systems(RRS) 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 using the example of the construction and operation of a radio relay line on the route of the Great Moscow Circular Railway, the length of which is 420 km.
RRLs are a chain of transceiver stations (terminal, intermediate, node), installed at a line-of-sight distance (40 - 70 km in the frequency ranges up to 6 - 8 GHz and several km in the ranges 30 - 50 GHz) 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 direction of signal transmission and receivers with demodulators in the direction of reception. 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). In this case, modems can work with transceivers using different frequency ranges. Transmitters are designed to convert intermediate frequency signals into the microwave operating range, and receivers are designed to inversely convert and amplify intermediate frequency signals.
There are RRL systems with direct modulation of microwave (super high frequency) signals, but they have limited distribution.
RRL classification
Two types of RRL: line of sight and tropospheric.
By purpose: intercity 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 the HF signal is greatly attenuated in precipitation.
According to the method of compaction and type of modulation: with PDK, with VRK and analog pulse modulation, digital RRL.
In terms of throughput: high-capacity RRL (more than 100 Mbit/s), medium-capacity for zonal communications - 60...300 k (10-100 Mbit/s), low-capacity for local and departmental communications. Multiple trunks are used to increase throughput.
Radio relay lines on the railway provide the organization of trunk, road and department connections. An approximate diagram of a railway radio relay line includes 3 radio channels. Intermediate points of the main and road trunks are located at a distance of 30 - 50 km, while industrial points with dedicated canals are built near railway stations, where road departments and departments are located, as well as junction and large stations. Industrial stations with separate separation shaft channels are located at all railway stations at a distance of 5 to 25 km. Various types of signals can be transmitted through a communication channel: telephone (conversation), sound or television broadcasting, telegraph, telecontrol, etc.
The separation equipment in combination with the 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. At RRLs, to increase their economic efficiency and capacity, several parallel operating radio channels are organized, equipped with the same type of transmitting and receiving radio equipment. The equipment of adjacent trunks operates at different carrier frequencies, but on common antennas. It is connected to the antenna-feeder system through isolation 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, to transmit multichannel telephony signals, telephone trunks with a capacity of 60 channels each are organized. Television programs (video and audio signals) are transmitted in a special television trunk ///. In this case, the video signal (image) and the audio signal can be transmitted jointly 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 transmitting and receiving radio equipment (operating in the microwave range), antenna-feeder devices, separation equipment, power supply devices, to auxiliary equipment- devices for service communication, telecontrol, telesignaling, control and measurement.
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 antennas should ensure direct visibility between them. Depending on the terrain, the height of the 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 and transmitting equipment is placed in the top floor of a monolithic reinforced concrete tower, and antenna devices are placed on its roof. Power equipment is installed in the lower floors of the tower.
Moving alarm. General information
Places where railway tracks cross at the same level as roads, tram tracks and trolleybus lines are called railway crossings. For traffic safety, crossings are equipped with fencing devices. On the side of trackless transport, automatic traffic light signaling, automatic barriers and half-barriers, non-automatic barriers with manual mechanical or electric drive together with warning (automatic or non-automatic) alarms are used as standard fencing devices.
With automatic traffic light signaling, the crossing is fenced with special crossing traffic lights, which are installed before the crossing on the side of the road on the right side for the movement of trackless vehicles. Red traffic lights are directed towards the road; they do not light up normally, indicating the absence of trains on the approaches to the crossing, and allow horse-drawn transport to move through the crossing. As the train approaches the crossing, the crossing traffic lights begin to flash alternately, and the bells ring at the same time. From this moment on, the movement of horse-drawn vehicles through the crossing is prohibited. After the train has passed through the crossing, the traffic lights go out, the bells are turned off, and trackless vehicles are allowed to move through the crossing.
With automatic traffic light signaling with automatic barriers, in addition to crossing traffic lights, the movement of vehicles is blocked by a barrier beam. For better visibility, the barrier is painted with red and white stripes and equipped with three lights. Two of them (the middle one and located at the base of the beam) are red, one-sided. They flash red lights towards vehicles. The third lantern, located at the edge of the beam, is double-sided. It lights up red towards vehicles, and white towards the railway track, indicating the border of the blocked part of the road at night.
The barrier or half-barrier beam in the lowered (barrier) position is held at a height of 1-1.25 m from the road surface and blocks vehicles from entering the crossing. When a train approaches a crossing, the barrier beam does not lower immediately after the alarm starts working, but after some time (5-10 s), sufficient for vehicles to pass the barrier, if at the time the alarm was turned on, the vehicle was close to the barrier and the driver could not see red traffic lights. When the barrier beam is in a horizontal position, the lights on the crossing traffic light and beam continue to burn, and the bell turns off. After the train has passed the crossing, the barrier bar rises to a vertical position, the lights on the bar and the traffic light go out, and the movement of trackless vehicles through the crossing is allowed.
Automatic half-barriers, in addition to devices that ensure their automatic operation when trains move, are equipped with non-automatic control devices. The devices are placed on the control panel, the installation location of which is chosen so that the crossing officer on duty at the control panel can clearly see the approach routes of trains and cars.
Buttons for closing and opening the half-barrier are installed on the control panel; button for turning on the barrier alarm (normally sealed); light bulbs that control the appearance of trains at the approaches to the crossing, indicating the direction of train movement; four light bulbs that monitor the serviceability of the traffic light circuits.
If necessary, by pressing the Close the barrier button, the crossing guard can turn on the crossing alarm, which in this case works in the same way as when a train approaches the crossing. After returning (pulling) the button, the half-barrier beam rises to a vertical position and the red lights of the traffic light and the beam go out.
If the automatic control system is damaged, the half barrier remains in the blocking position. If there are no trains on the way, the crossing duty officer can allow vehicles to pass through the crossing. To do this, he presses the Open barrier button. The half-barrier beam rises to a vertical position and the red lights on the traffic light and the beam go out. The button must be kept pressed until the vehicle passes the half-barriers. When the button is released, the half barrier returns to the horizontal position.
At crossings equipped with warning alarms, electric or mechanized barriers, controlled by the crossing duty officer, are used as fencing means. To notify the person on duty at the crossing, automatic or non-automatic light and sound warning alarms are used.
To signal the train to stop in the event of an emergency at a crossing, a barrier alarm is used. Special barrier traffic lights, automatic and semi-automatic blocking traffic lights and station traffic lights are used as barrier signals if they are no more than 800 m from the crossing and the crossing is visible from the place of their installation. Obstacle traffic lights, as a rule, are also mast-mounted; they have a different shape from regular traffic lights. The red lights of the traffic lights do not light up normally. They are turned on by the person on duty at the crossing by pressing the Turn off the traffic lights button on the dashboard. By returning (pulling) the button to its normal position, the traffic lights are turned off. At the same time, the lights on the dashboard light up, monitoring the proper operation of the traffic lights. If the control light does not light up when the barrier signal is turned on, this means that the traffic light is faulty and the person on duty at the crossing must take additional measures to protect the crossing from the side of the faulty traffic light.
In areas equipped with automatic blocking, when the barrier alarm is turned on at the automatic blocking signals closest to the crossing, their reading switches to prohibitive and the supply of ALS codes to the track circuits before the crossing stops.
The type of devices used at crossings depends on the category of crossing. On the road network, depending on traffic intensity and visibility conditions, crossings are divided into four categories:
Category I - intersections of railways with roads of categories I and II, streets and roads with tram and trolleybus traffic; with streets and roads along which there is regular bus traffic with a crossing traffic intensity of more than 8 train-buses per hour; with all roads crossing four or more main railway lines;
Category II - intersections with category III roads; streets and roads with bus traffic with a crossing traffic intensity of less than 8 train-buses per hour; city streets that do not have tram, bus or trolleybus traffic; with other roads, if the traffic intensity at the crossing exceeds 50,000 train crews per day or the road crosses three main railway tracks;
Category III - intersections with highways that do not fit the characteristics of crossings of categories I and II, and if the traffic intensity at the crossing with satisfactory visibility exceeds 10,000 train-crews, and with unsatisfactory (bad) - 1,000 train-crews per day. Visibility is considered satisfactory if, from a crew positioned at a distance of 50 m or less from the railway track approaching from any direction, the train is visible at least 400 m away, and the crossing is visible to the driver at a distance of at least 1000 m;
The intensity of traffic at a crossing is measured in terms of train crews, that is, by multiplying the number of trains by the number of crews passing through the crossing per day.
To automatically turn on fencing devices when a train approaches a crossing, approach areas equipped with track chains are arranged. The length of the approach section depends on the notification time, the speed of the train and is determined by the formula
The estimated notification time depends on the length of the crossing, the speed of movement of the crew through the crossing (assumed 5 km/h), the length of the crew (assumed 6 m) and the time of lowering the barrier beam (10 s), if the latter blocks the entire carriageway of the road.
When signaling with electric barriers, the required notification time must be increased by the time the crossing duty officer perceives the notification. In calculations it is taken equal to 10 s. On the Ministry of Railways road network, the minimum acceptable notification time for automatic traffic light signaling without barriers and with half-barriers is 30 s, for automatic barriers that completely block the roadway - 40 s, and for warning signaling - 50 s.
Automatic crossing signaling devices generally use the same equipment and equipment that is used in other railway automation devices. Special equipment includes crossing traffic lights, electric barriers and crossing alarm control panels. Crossing traffic lights without barriers are made with two or three traffic light heads. Adding a third traffic light head allows you to expand the visibility range of signal indications.
Electric barriers of the vertically rotating type are used (Fig. 141). It consists of a barrier beam 1, a cross-shaped signal sign 2 with glass reflectors, two unambiguous heads 3, an electric bell 4, a mast 5 attached to the electric drive housing with four bolts, an electric drive 6 and a foundation 7.
The barrier beam of a half-barrier, 4 m long, is completely balanced by weights and is moved from a closed position to an open position and back by an electric motor. During a power outage, the beam must be moved manually. To prevent the beam from breaking when a vehicle hits it, it is fixed in a horizontal position not rigidly, but by two ball latches on the barrier frame and can be rotated about its vertical axis by 45°. When raised, the beam is locked with a transfer mechanism.
The barrier's electric drive consists of a cast iron housing, in which a 95 W DC electric motor with a voltage of 24 V and a rotation speed of 2200 rpm is placed; gearbox with gear ratio 616; drive shaft and auto switch. When working, the gearbox rotates the drive shaft, which controls the barrier bar.
The autoswitch consists of three adjusting cams connected to the drive shaft, which close the contacts at different angles of lift of the barrier beam. A double-arm shock-absorbing device lever is connected to the drive shaft. The drive mechanism is equipped with a friction device that protects the electric motor from overloads.
Operating principle of UZP (Crossing Barrier Device)
The barrier device works as follows: when the drive electric motor is turned on, first the drive lock that held the cover in the lowered position falls off, then, under the influence of the counterweight and the drive gate, the ultrasonic cover is raised at an angle of 30; at the end of the lid lifting phase, the auto switch is triggered and the electric motor is turned off, preparing the power circuit for turning the electric drive back on. Barrier devices, like auto barriers, have dual control - automatic and non-automatic - pressing buttons on the APS panel. In both cases: turning on the signal lights, moving the barrier bars to horizontal (when closing) and vertical (when opening), the ultrasonic covers to the raised (obstructing) - lowered (allowing passage) positions are carried out by de-energizing and, accordingly, energizing the PV relay (in the APS control cabinet ) and its repeaters (in the SPD cabinet). The barrier device works as follows (see Appendix 8). When a train appears in the section approaching the crossing in the relay cabinet of the crossing alarm, the PV relay is de-energized, the PV1 relay is energized, the red flashing lights of the crossing traffic lights are turned on, the UZ cover zone vacancy control system is turned on, and after about 13 s the VM relay is de-energized and the barrier bars begin to lower. From the moment the VM relay is de-energized in the UZP relay cabinet, the VUZ relay (UZ turn-on relay) is turned on, after about 3 s, the BVMSh delay unit is activated, and the relay for lifting the protective UZ, UP and VUZM covers is activated. The friction relay F and the NPS relay are activated, the contacts of which control the ultrasonic drives. The activation of the PPS relay of each of the drives is possible provided that the zones of the ultrasonic covers are free. The control of the free zones of the ultrasonic protection covers is carried out by the front contacts of the safety protection relay, which receives power from the safety protection sensor. RN relays monitor the presence of voltage from the control outputs of the KZK sensors. After the PPS and NPS relays are triggered, power is supplied to the electric motors of the drives; within 4 s, the covers of the UZ occupy a blocking position, preventing vehicles from entering the crossing. Switching off the electric motors of the drives after lifting the covers of the ultrasonic switch is carried out by the working contacts of the autoswitch. In the case of the electric motors of the drives operating on friction (UZ covers cannot be raised or lowered due to the presence of an obstacle), the NPS relay and electric motors are turned off by the contacts of the friction relay F, which has a drop-off delay of 6 - 8 s. After the PPS and NPS relays are triggered, power is supplied to the electric motors of the drives; within 4 s, the covers of the UZ occupy a blocking position, preventing vehicles from entering the crossing. The electric motors of the drives are turned off after lifting the ultrasonic covers by the working contacts of the autoswitch. In the case of the electric motors of the drives operating on friction (UZ covers cannot be raised or lowered due to the presence of an obstacle), the NPS relay and electric motors are turned off by the contacts of the friction relay F, which has a drop-off delay of 6 - 8 s. The electric motors of the drives are powered from a rectifier device (BP) (VUS-1.3). In case of failure of the main rectifier device BP 1, the contacts of relay A2 switch to the backup rectifier device BP 2 (VUS-1,3). After the train has passed the crossing, the PV relay is excited in the APS relay cabinet and the VUZ relay is turned off in the UZP relay cabinet. The electric motors of the drives begin to work to lower the ultrasonic covers. After the covers are lowered, relays 1PK - 4PK are excited. With the control of the excitation of relays 1PK - 4PK, the relay circuit U1, U2 is closed in the APS relay cabinet, which also controls the raising of the barrier bars, and the red flashing lights of crossing traffic lights are turned off. The person on duty at the crossing also has the opportunity to bring the UZ covers into the blocking position or lower them. In the first case, he needs to press the “closing” button on the APS panel: in the APS cabinet the PV relay is de-energized, the crossing alarm devices are turned on, and in the UZP relay cabinet after 13 s the VUZ relay is triggered and, as in the case of automatic notification of the approach of a train , the US covers are lifted. To lower the UZ covers, you need to pull out this button. For emergency lowering of the UZ covers, you need to break the seal on the UZ panel with the “normalization” button and press it. The covers of all ultrasonic devices are lowered, and the ultrasonic device is switched off from operation. However, in this case, turning off the flashing red lamps of crossing traffic lights is carried out without controlling the lowering of the UZ covers. Also, a decision was made to eliminate the blinking of the red lamps of crossing traffic lights after pressing the “normalization” button in the event of loss of control of the position of the ultrasonic covers on the contacts of the autoswitches of the ultrasonic drives. The person on duty at the crossing, when pressing the “normalization” button, must make sure that the covers of the control unit are lowered and, if any cover is not in the lower position, finish the operation of the drive using the crank handle. On the UZP panel, to monitor the positions of the covers and the state of the KZK sensors, there are three rows of light bulbs (LEDs) with 4 light bulbs (LEDs) in a row. The top row signals through the control contacts of the drives about the raised, upper position of the covers, the middle row through the front contacts of relays 1PK-4PK - about the lower position of the covers, and the bottom row, with an even burn, signals the serviceable state of the KZK sensors, and by blinking it signals a sensor malfunction. If there is no train in the approaching section, the bottom row of lights (LEDs) does not light up. Three buttons are installed on the UZP panel: - two non-latching, non-sealable buttons, “exit 1” and “exit 3” - for lowering the covers of the first and third UZ, respectively, when vehicles exit the crossing; - a button with a fixation, sealable, “normalization” - for lowering the covers of the ultrasonic device and turning the ultrasonic device off from operation in the event of a malfunction. The control of the non-pressed position of the “normalization” button on the UZP panel is carried out by the lighting of the “normalization” light bulb (LED).
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 at crossings 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 And unregulated. Regulated crossings include crossings equipped with crossing signaling devices that notify vehicle drivers about the approach of a train crossing, and/or serviced by employees on duty. The possibility of safe passage through unregulated crossings is determined by the driver of the vehicle independently in accordance with the Road Traffic Rules of the Russian Federation.
The list of crossings serviced by the employee on duty is given in the Instructions for the operation of railway crossings of the Russian Ministry of Railways. Previously, such crossings were briefly called “guarded crossings”; according to the new Instructions and in this work - “moving with an attendant” or “attended moving”.
Crossing alarm systems can be divided into non-automatic, semi-automatic and automatic. In any case, a crossing equipped with a crossing alarm is protected by crossing traffic lights, and a crossing with a man on duty is additionally equipped with automatic, electric, mechanized or manual (horizontally rotating) barriers. At crossing traffic lights There are two red lamps located horizontally, which burn alternately when the crossing is closed. Simultaneously with the switching on of crossing traffic lights, acoustic signals are switched on. In accordance with modern requirements, at certain crossings without an attendant, the red lights of crossing traffic 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 devices; when closed, it does not light. When the white-moon light is extinguished and the red lights are not lit, vehicle drivers must personally ensure that there are no approaching trains.
The following are used on Russian railways: types of crossing alarms :
1. Traffic light signaling. Installed at crossings of access roads and other tracks where approach areas cannot be equipped with rail chains. A prerequisite is the introduction of logical dependencies between crossing traffic lights and shunting or specially installed traffic lights with red and moon-white lights that serve as barriers for railway rolling stock.
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 after the crossing is closed with a time delay that ensures 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 to the listed devices, 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 turns on the technical means of fencing the crossing. After the train has passed, the attendant opens the crossing.
