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Publication numberUS3748466 A
Publication typeGrant
Publication dateJul 24, 1973
Filing dateJun 14, 1971
Priority dateJun 14, 1971
Also published asCA954968A1, CA960346A1, DE2228126A1
Publication numberUS 3748466 A, US 3748466A, US-A-3748466, US3748466 A, US3748466A
InventorsJ Auer, H Sibley, W Smith
Original AssigneeGen Signal Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Vehicle control system
US 3748466 A
Abstract
The vehicle control system operates vehicles over the right-of-way divided into a plurality of zones and has control means for governung safe operation of the vehicle in accordance with traffic conditions. The improvement comprises means of selecting both a desired speed limit and speed command control for communication to the vehicle occupying any of the zones in accordance with the conditions of traffic in advance of the zone, the selecting means is effective to select a relatively low command speed control zone in accordance with the selection of a relatively low speed control for at least one zone in advance of the vehicle in accordance with the safe stopping distance. Means communicates the selected limit and command speeds for each zone from the wayside to the vehicle occupying the zone and means controls operation of each vehicle in accordance with the selected speed limit and speed command controls communicated to the vehicle from the wayside.
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Description  (OCR text may contain errors)

United States Patent 1 Sibley et al.

[ 1 July 24, 1973 VEHICLE CONTROL SYSTEM [75] Inventors: Henry C. Sibley, Adams Basin; John H. Auer, Jr., Fairport; Willis R. Smith, Rochester, all of N.Y. [73] Assignee: General Signal Corporation,

Rochester, NY.

[22] Filed: June 14, 1971 211 App]. No.: 152,845

[52] US. Cl 246/63 C, 246/187 B [51] Int. Cl B61] 23/16 [58] Field of Search 246/63 C, 34 R, 187 B [56] References Cited UNITED STATES PATENTS 3,395,274 7/1968 Baughman 246/34 R X 3,303,339 2/1967 Dell 246/63 C 3,041,448 6/1962 Pascoe et a]... 246/63 C 3,045,] 12 7/l962 Hailes 246/63 C SVIZITCH MASTER CODE 22 GENERATOR TERMINAL PROCESSOR [57] ABSTRACT The vehicle control system operates vehicles over the right-of-way divided into a plurality of zones and has control means for govemung safe operation of the vehicle in accordance with traffic conditions. The improvement comprises means of selecting both a desired speed limit and speed command control for communication to the vehicle occupying any of the zones in accordance with the conditions of traffic in advance of the zone, the selecting means is effective to select a relatively low command speed control zone in accordance with the selection of a relatively low speed control for at least one zone in advance of the vehicle in accordance with the safe stopping distance. Means communicates the selected limit and command speeds for each zone from the wayside to the vehicle occupying the zone and means controls operation of each vehicle in accordance with the selected speed limit and speed command controls communicated to the vehicle from the wayside.

6 Claims, 20 Drawing Figures PAIENIEU 3. 748 466 sum 01 or 1s MASTER CODE 22 GENERATOR FIG. 1A TERMINAIEIPROCESSOR 69 MAGNETIC IITIHINI ej loj joji: TO IDENTIFICAT|0N R5 62 CENTRAL READER OCCUPANCY CONTROL THROUGH 6| DETECTOR MCG 22 63 /6O POSITION CENTRAL ROUTE COMMAND NTRO 'INITIALIZATION V FILTER DETECTOR Co L LOGIC SELECTOR 68 DOOR OPEN LEVEL DETECTOR FIG. 5

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F L 5 5E 55 95 J TERM! PROCESSOR OVERSPEED 8 MOTION DETECTOR EMERGENCY BRAKE USR I l I K {H C m w H M L 8 MW u 8 IQV 9 9 7 9 O 3 +1 9 R -m 9 m /@0 0 /K S 0 A E TE L P N OT E L 5 E 0 O CC T 0 H ME D L 0M OE O R0 THTR H ET C RVN A EEO T BLC Pmzmzum 3.748.466

saw on HF 1 A B c D E F {W 1 H 1 H 1 H 1 M 1 0 1 I H I M I M I 0 I O I #CL'EAR BLOCKSI AVP AVO FIG. 5

I A I B I C I D I E I F I T I I I I I I l l l l 32 l $3 s1= ZBLOCKS H+M AVO {s2= 1 BLOCK M+ o S3=2BLOCKS H+O AVP s4= 1 BLOCK M+ o FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. FIG. 1A 18 7A 7B 70 8A 8B IOA IOB FIG. FIG. 12A 12B FIG.13

PATENTEDJULZMQH SHEET FIG.7C

I I I I I I I I I I I I I l I I I I I I l I I l I I I I (VITAL) FAIL-SAFE DRIVER DEMODULATO I l l CONTACT ARRAY (SC) DETECTOR CHANNEL 1 ON BOARD SHEET 10 [1F 1 6 PAIENIEIJ M24375 L +III- a IIII II n R R A :m w H M m u 2 3 N F F O IIIIIIT E c n I I I l I IIIIII I .IIIIII I ace 0 H H D wm m mm m LMH H L Z D K 0 S ET D C 0 O III uw E EM 0 E E P m P M TSN SL Smw TO SPEED M/L SELECTOR NETWORK 24 LIMIT/COMMAND F1 L/O F2 M/O WAYSIDE FSK OSCILLATOR F1 -I23 FSK OSCILLATOR F2 FSK OSCILLATOR F 3 MODULATOR FREQUENCY GENERATOR SAFETY CODE VEHICLE CONTROL SYSTEM BACKGROUND OF INVENTION This invention relates to a vehicle control system and in particular to the system for controlling automatically the operation of a plurality of vehicles along a guideway from a centralized location.

Operatorless automatic vehicle control systems re quire a number of safety and supervisory sub-systems for safe and efficient operation. Normally, an automatic vehicle protection system is necessary which must be substantially fail-safe in order to provide for safe public transportation. An automatic vehicle operation subsystem is included in order to provide the normal control of the vehicle within the restraints of the safety sub-system and a supervisory system is provided in order to provide such functions as, for example, performance monitoring, route control or other supervisory requirements.

The basic functions of an automatic vehicle control system must provide for protection of trains from headon and rear-end collisions, speed regulation and, of course, safe passenger door operation. In addition, the system which operates automatically must establish safe remotely controlled switch routing and checking and include vehicle responsive apparatus which operates in accordance with certain supervisory controls.

When utilizing other than typical railroad vehicles for the transportation of persons in a rapid transit system, new concepts are employed in order to provide a safe system which encounters problems unique to nonrailed vehicles. An obvious example would be the use of a vehicle shunt to determine the position of the train in the system, while with non-rail vehicles, it is apparent that some other system must be utilized which is at least as reliable as the vehicle shunt for determining the position of the vehicle.

To those familiar with railroad signaling art, it is obvious that conventional track coupled signaling means is not effective with a railess or air cushioned vehicle and that some effective means must be devised in order to communicate effectively between vehicle and the wayside and a centralized control location.

It is therefore an object of the present invention to provide an arrangement which substantially obviates one or more of the limitations and disadvantages of the described prior arrangements.

It is another object of the present invention to provide a system which may effectively determine the position, direction and safe speed of an automatically controlled vehicle.

lt is another object of the present invention to provide an improved system for communicating between the vehicle and the wayside for maintaining those communications in a safe manner.

SUMMARY OF INVENTION A vehicle control system has been provided for operating vehicles over a right-of-way divided into a plurality of zones having control means for governing safe operation of the vehicles in accordance with traffic conditions. The improvement comprises, means for selecting both the desired speed limit control and speed command control for communication to the vehicle occupying any of the zones in accordance with conditions of traffic in advance of such zone. The selecting means is effective to select a relatively low command speed control for each zone in accordance with the selection of relatively low limit speed control for at least one zone in advance of the vehicle in accordance with the safe stopping distance. Means is provided for communicating the selected limit and command signal for each zone from the wayside to the vehicle in the associated zone and means for controlling operation of each vehicle is included which operates in accordance with the speed limit and speed command controls communicated to the vehicle from the wayside.

There is included in a vehicle control system an overspeed detection apparatus including a pair of high pass filters having inputs governed by actual vehicle speed signals for delivering outputs of the respective filters in accordance with the actual speed limit inputs only provided that the frequency of the inputs is above the frequency of the high pass filters. Checking means is provided including an oscillator generating and check signal having a frequency higher than the frequency of the high pass filters and a switching means for alternately applying the check frequency to the inputs of the filters so that the filters alternately deliver output check frequency signals. The output means is governed jointly by the output of the high pass filters and is operable to one state or another only when one of the filters at a time is delivering an output, or operable to the other state when both filters deliver outputs comtemporaneously.

The vehicle control system has means on the vehicle for demarcating the ends thereof and wayside marker means at an entering boundary for zones responsive to the passage of each end of the vehicle for respectively assuming first and second conditions in accordance with the passage of an odd or even number of demarcating means respectively. Occupancy means for each zone is responsive to its associated wayside marker and registers occupancy in accordance with the first condition until cancelled while reset means governs the occupancy means and is itself governed jointly by the first condition for the next two wayside markers in advance of the vehicle and the second condition for its associated marker for cancelling the occupancy indication.

The control system includes means for selecting the direction of traffic along a guideway and means responsive to the vehicle presence upon entering a zone from either direction for registering the occupancy condition thereof. The means governed jointly by the occupancy responsive means and the direction selecting means renders the control means operative to restrictive aspects in accordance with the selected number of zones behind the leading vehicle relative to the selected direction of traffic.

For a better understanding of the present invention, together with other and further objects thereof, refer ence is had to the following description taken in connection with the accompanying drawings, while its scope will be pointed out in the appended claims.

DESCRIPTION OF THE DRAWINGS FIGS. 1A and IB are diagrams of the general plan of the present invention.

FIG. 2 is a diagram of vehicle carried control equipment.

FIG. 3 is a diagram of wayside equipment used in conjunction with the vehicle carried control equipment.

FIG. 4 is a detail of the overspeed and motion detector from FIG. 2.

FIG. 5 is a diagram showing the distribution of speed limit and command controls for a number of occupied blocks.

FIG. 6 is a diagram showing safe stopping distances for speed limit control and speed command control.

FIGS. 7A-BC illustrate the check in-check out safety subsystem.

FIGS. 8AB are further illustrations of apparatus shown in block form in FIG. 5.

FIG. 9 is a drawing showing means to communicate speed limit and speed controls from the wayside to the vehicles.

FIGS. lA-B show an alternate embodiment of a check in-check out system.

FIG. 11A is a drawing of vehicle to wayside transmission means.

FIG. [18 is a drawing of vehicle to wayside receiver means.

FIGS. l2A-B show means to transmit logic for communication from the wayside to the terminal processors.

FIG. 13 shows the relation of partitioned drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The system of the present invention generally includes systems for automatic vehicle protection AVP, automatic vehicle operation AVO, and automatic vehicle supervision AVS.

The automatic vehicle protection safety subsystem includes normally located wayside elements for vehicle protection, block occupancy memory, vehicle control signal generation, selection and transmission, switch interlocking and control, and platform door control. On the vehicle, safety hardware is included for receiving vehicle control signals, for governing the maximum speed, for initiating irrevocable stops on either a service or emergency brake basis as required, for permitting automatic door operation only when safe, and for preventing automatic movement in the reverse direction.

Other parts of this system which are necessary for efficient controls of the vehicle include transmitters and receivers for communicating digital information from the lead vehicle of these trains to the wayside at approaches to switches and station platforms. These messages contain information relative to the routing of the vehicle, the identity and malfunction status, and station operation. Apparatus is also provided for communicating digital data from the wayside to terminal processers serving a number of designated areas. These terminal processers serve as intermediate links between the wayside and the central processing unit.

A general description of this system proceeds as follows in respect to FIGS. IA & 1B. The system comprises a guideway layout GW divided into a number of blocks of which blocks A through G are shown in the drawing. Vehicle VI travels within the guideway GW in one of a number of selected routes as established by commands communicated from the vehicle VI to the wayside for controlling the switches SW. Each block includes a wayside loop 20 which extends the full length of the block for continually transmitting information to the vehicle within the particular block, in this case vehicle V]. A terminal processor 21, couples the apparatus with a centralized location having a master process control computer, not shown. Communications from the computer are transmitted to each vehicle (and individual wayside located apparatus) over the terminal processor 21 for a selected area. Each terminal processor 21 provides a link between the computer and a number of related blocks. Each block includes communication apparatus linking the terminal processor 21 and the vehicle V1 located therein.

The terminal processor 21 includes a master control generator 22 which in this embodiment produces a number of code rate frequencies. For purposes of speed selection, three frequencies F1, F2 and F3 are utilized, F1 and F2 respectively indicative of low and medium speed limits and the combination of F1 and F2 high speed limit. F3 is used in conjunction with the F1 and F2 signals for varying command speeds transmitted to the vehicle V1. That is, F1 and F2 are used to designate speed limits, while combinations of F1, F2 and F3 indicate the command speeds which are less than or equal to speed limit signals. Speed commands are used in conjunction with speed limits of low, medium and high as shown in the following table:

2 5 Speed Limit zero low medium high th high Speed Command zero zero zero low tg medium th high Signals none F1 F2 F2, F3 F1, F2 Fl,F2,

The additional frequency F3 is utilized to add versatility to the system so that speed commands and speed limits have different characteristics. In addition, the F3 signal is communicated over non-vital apparatus because it is not necessary to provide fail-safe communications for the speed command. The reason for this is that the speed limits control and the vehicle will go into an emergency stop condition if it is travelling faster than the speed limit signal permits regardless of the speed command signal.

The layout of FIGS. 1A & 1B illustrates the general configuration of the system with respect to communication of speed limits and speed controls to the loops 20 in accordance with the condition of blocks in advance of the vehicle V1. Each block has a block occupancy sensor 23 which read transmitters 28-28 for demarcating the ends of the vehicle. When the front or leading end of the vehicle encounters the sensor 23, occupancy is registered for that block, in this case, block C. Occupancy detector 24 registers the occupancy of the vehicle in block C and transmits a signal rearwardly to speed selection units 25 for at least four previous blocks. It should be noted that this diagram is a plan view of the system and it is intended that the vehicle may travel in either direction along the guideway GW. For purposes of simply illustrating the concept of the invention in this drawing, control is shown only for one direction; that is, from left to right. The drawing shows the vehicle VI in block C, therefore, the detector 23 has provided a signal to the occupancy detector 24 for registering occupancy of the vehicle V1 in block C. In addition, the speed selectors 25 for the preceding four blocks receive a signal that block C is occupied and their speed controls are adjusted in accordance with a preselected speed limit pattern for this configuration. Such a pattern, for example, may provide that block B directly in back of the vehicle is at stop, while block A is at low speed and the previous two blocks, not shown,

may be at some medium or high speed in accordance with the safe stopping characteristics of vehicle V1 following. For purposes of this discussion, however, it is only necessary to show that some selected number of blocks rearward of the vehicle must be informed of the occupancy status of the vehicle.

The occupancy detector 24 provides a signal to OR gate 26 which initiates a signal to amplifier 27 which is keyed for enabling communication of speed code signals to the loop from the speed selection unit associated with block C. In addition to keying the amplifier 27 for the loop 29 in block C, a line 28 is also coupled to the OR gate 26 for block D in advance of the vehicle; so that block is keyed for the approach of the vehicle V1 as it crosses from C to D. When the vehicle Vl leads or crosses the boundary into block D, its condition is detected for block D by the sensor 23 and registered in the associated occupancy detector 24 for block D. This condition is immediately communicated to the speed selection unit 25 for block C which resets the occupancy detector for block C along lead 29. This cuts off the input to OR gate 26 along lead 30 and removes the keying from the amplifier 27 for block C. Under these conditions, the vehicle entering block C while block D is occupied will be placed in an irrevocable emergency braking situation because no signals are communicated to loop 20 for block C. Such a condition is indicative of a malfunction because, as previously stated, at least one clear block must be provided rearward of a vehicle. As the train progresses along the guideway GW, it keys the block ahead and resets the block behind thereby providing itself with a protective zone and information relative to its position is communicated to at least four blocks rearward of the vehicle so that trains following may be safely controlled in accordance with stopping distances which are characteristic of the vehicles used in this system.

Frequency signals generated by the speed selection unit 24 are communicated to the vehicle V1 over the loop 20 via receiver antenna illustrated in FIG. 2. Filter 41 passes frequencies F1, F2, F3 and they are communicated through amplifier 42 to modulation detector 43. The modulation detector 43 is capable of picking out the speed limit and command signals and energizing relays in accordance with the transmitted signals for energized inputs to speed control 44 which governs the running speed of the vehicle. Other signals including a modulation frequency for the door control 46 may also be transmitted through the antenna and decoded at 43 for operating the doors in accordance with the proper positioning of the vehicle at a station platform.

Overspeed and motion detector is responsive to the modulation detector 43 for holding off emergency brake release and the power controller 51. An input from tachometer 47 compares the actual vehicle speed with the speed limit as detected by signals from the modulation detector 43. The emergency brake release 50 may be a mechanically actuated apparatus which holds off application of the emergency brakes in accordance with a signal from the overspeed and motion detector 45 if the speed limit signal is lower than the actual speed as determined by the tachometer 47. Power controller 51 is coupled to the emergency brake release and decouples motive power for the vehicle Vl when the emergency brakes are released so that the vehicle will come to a safe and rapid stop when an unsafe condition is detected. Direction detector 49 provides a signal to the motion detector 45 for assuring that the vehicle is travelling in the proper direction and the brake assurance unit accelerometer 48 provides a signal to the detector 45 for acknowledging that the vehicle is slowing down in accordance with a change in speed limit or speed command signals as provided through the detector 43.

The motion detector 45 signals a door control apparatus 46 for preventing their operation if the vehicle V1 is moving at the train platform. When the train is stopped, a holding brake detector 52 governing the door control 46 assures that the brakes have been applied. Inputs from the brake detector 52 and the motion detector 45 are transmitted to levitation control 53 which deleviates the car V] at the station platform. The levitation of the vehicle may be an air bag suspension or an air cushion system, but for purposes of this discussion it is important to note only that it is necessary to align the vehicle V1 with the station platform longitudinally within the limits of a berthing loop on the wayside (see FIG. 3) and also level with respect to the station platform. When leveling is complete, the signal is communicated to berth tone generator 54 which produces a distinctive tone for transmission at its output loop 55.

A berthing loop 60 located mainly at the station platforms or docking areas receives a signal from the berth transmitting loop 55 if the vehicle Vl has stopped within the confines of the loop 60. A signal from the transmitting loop 55 is fed through filter 64 detector 65 and level detector 66 before a door open command may be provided to the command selector 67. These constraints assure first that the vehicle has stopped, the brakes have been applied, the vehicle is level with respect to the train platform and finally that the vehicle Vl has stopped within the proper confines of the berthing loop 60. When a door open command is initiated, the command selector 67 provides a signal to amplifier 68 for opening the doors, this signal is received atantenna 40 and filtered at 41 amplified at 42 and decoded in the demodulator 43. The door open command which would be some distinctive frequency is transmitted to door control 46 for actuating the vehicle doors. It should be noted as stated with respect to FIG. 3 that the occupancy sensor 61 and occupancy detector 62 must key the OR gate 63 so that the amplifier 68 is capable of transmitting the command signal for a door open designation to the vehicle.

After a selected dwell time as determined by the central control unit, a signal from control is coupled to command selector 67 for deactivating the door open command which essentially cuts off the distinctive door control frequency which is transmitted over the loop 60 to the vehicle V1. The doors on the vehicle then close in accordance with the cessation of the door open command signals and if the vehicle doors properly close, levitation control 53 is apprised of this condition and actuates apparatus'for raising the car to its operative position. The brakes of the vehicle are also released in this sequence and when brake release is detected, speed control 44 is conditioned for accepting signals from the wayside for proceeding to the next scheduled stop.

As described with reference to FIG. 3 in accordance with the occupancy of the blocks ahead of the vehicle V1 command speed selector 67 provides signals to the

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3848836 *Dec 26, 1973Nov 19, 1974Saab Scania AbCar actuated inductive block control
US3858832 *Aug 1, 1973Jan 7, 1975Rolair Syst IncControl system for air cushion transporter
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Classifications
U.S. Classification246/63.00C, 246/187.00B
International ClassificationB61L27/04, B61L27/00, B61L23/00
Cooperative ClassificationB61L27/04, B61L23/00, B61L27/0038
European ClassificationB61L23/00, B61L27/04, B61L27/00C