TRAIN CONTROL DEVICE

- Kabushiki Kaisha Toshiba

A train control device includes a detector that detects the current location and speed of the train, a clock unit that tracks the current time, a schedule input section by which the schedule data including the scheduled arrival time of the train at each station on the line is input, and a computing unit that computes an operating schedule according to which the train runs at the detected location and the detected speed to the next station, based on a target operation time that is obtained by subtracting the current time from the scheduled arrival time at the next station, operation characteristics of the train and a condition of the line.

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Description
CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2012-123725, filed May 30, 2012; the entire contents of which are incorporated herein by reference.

FIELD

Embodiments described herein relate generally to a train control device.

BACKGROUND

Conventionally, a car such as a train car has a device for Automatic Train Operation (ATO) to prevent delays and to maintain regular operations. The ATO follows the predefined operating schedule for a section between one station and the next station, and regulates a variety of controls such as an operating speed control and braking control.

An operating schedule of the ATO is computed according to the line data or the train model data so that an operation time of the operating schedule approximates the predefined operation time for each station. However, it is not prepared considering the arrival time at the next station. Thus, in the related art, once departure is delayed, arrival time at the next station may also be delayed.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating the configuration of a train control device according to a first embodiment.

FIG. 2 is a flow chart illustrating one example of the operation of the train control device according to the first embodiment.

FIG. 3 is a conceptual diagram illustrating an operating schedule.

FIG. 4 is a conceptual diagram illustrating an operating schedule with a passing station.

FIG. 5 is a conceptual diagram illustrating an operating schedule with a passing station.

FIG. 6 is a conceptual diagram illustrating an operating schedule with a passing station.

FIG. 7 is a block diagram illustrating the configuration of a train control device according to a second embodiment.

FIG. 8 is a conceptual diagram illustrating a relationship between a speed braking pattern estimated from the speed limit and the operating schedule.

FIG. 9 is a conceptual diagram illustrating an example of re-computing the operating schedule when a gap with preceding train expands.

DETAILED DESCRIPTION

In general, according to one embodiment, a train control device of the present embodiment will be described below with reference to the drawings.

In order to solve the above problem, a train control device in the present embodiment includes a detector that detects a current location and speed of the train, a clock unit that tracks a current time, a schedule input section by which schedule data including a scheduled arrival time of the train at each station on a line is input, and a computing unit that computes an operating schedule according to which the train runs at the detected current location and the detected speed to the next station based on a target operation time that is obtained by subtracting the current time from the scheduled arrival time at the next station, operation characteristics of the train and a condition of the line.

First Embodiment

FIG. 1 is a block diagram illustrating the exemplary configuration of a train control device 1 according to a first embodiment. As shown in FIG. 1, a train T is equipped with the train control device 1, and a driving and braking control device 3 that drives and stops the train T based on a powering command and a braking command from the train control device 1. The driving and braking control device 3 drives or brakes wheels 2 and the train T runs on a rail R. The driving and braking control device 3 includes an inverter to control a motor, and a brake controller for controlling a pneumatic brake by a braking device and an electric brake by a motor.

The train control device 1 includes: a speed and location detector 10, an on-board automatic train control (ATC) device 20, an ATO device 30, a schedule input unit 31, a database 32, a timing unit 33, and a display device 60. The speed and location detector 10 detects a speed of the train T on the rail R and a location of the train on the line. More specifically, the speed and location detector 10 detects a speed of the train T from the output value of a TG (tacho generator) 12 that is coordinated with the rotation of the wheel 2. The TG 12 can be a pulse generator (PG) that is coordinated with the rotation of the wheel 2. The speed and location detector 10 detects the current location of the train T on the line based on the travel distance calculated by integrating the speed of the train T and a signal, which a pickup coil on an on-board antenna 11 receives from an inductive coil of a beacon 13. The current speed and location of the train T, which the speed and location detector 10 detects, are output to the on-board ATC device 20 and the ATO device 30 as the speed and location information.

The on-board ATC device 20 receives information through a receiver 21 from a sideway ATC device 22 as an analog signal via a track circuit 23 of a rail R, and outputs a braking command to the driving and braking control device 3 based on the received information and the speed of the train T. The information received from the sideway ATC device 22 includes a signal indication speed that indicates maximum speeds (shown as “speed limit” in the drawings) at a block section where the train T is located. The on-board ATC device 20 compares the signals indication speed, as notified by the sideway ATC device 22, and the speed of the train T and outputs a braking command to the driving and braking control device 3 if the speed of the train T exceeds the signal indication speed. The on-board ATC device 20 also transfers the signal indication speed to the ATO device 30.

The ATO device 30 outputs a powering command and a braking command under the control of the on-board ATC device 20 to the driving and braking control device 3. More specifically, the ATO device 30 outputs a control command (a notch command) such as a powering command and a braking command to the driving and braking control device 3 so that the train T is operated at a speed within the signal indication speed, which is output by the on-board ATC device 20 and is based on the current location of the train T detected by the speed and location detector 10.

The ATO device 30 also computes the operating schedule according to which the train T with the current location and the speed, as detected by the speed and location detector 10, operates and approaches the next station based on the operation characteristics and the condition of the line (detail will be described below). This operating schedule is data that defines sections and curve lines for powering, coasting, and braking, in order to stop the train T at a target position, which is the next stop, at a predetermined operating time. The ATO device 30 then operates the train T based on the operating schedule that it computed.

During automatic operation, the ATO device 30 outputs the powering command and the braking command to the driving and braking control device 3 based on the operating schedule. Consequently, the train control device 1 operates the train T in accordance with the operating schedule. During manual operation, the ATO device 30 displays a target speed based on the operating schedule on the display device 60. An operator operates a master controller (not shown) based on the target speed displayed on the display device 60 and manually operates the train T in accordance with the operating schedule.

The schedule input unit 31 accepts the schedule data including a scheduled arrival (passing) time of the train T at each station on the line. More specifically, the schedule data is accepted by either a wireless communication mediated by a communication device 40 or loading the data stored in a memory unit 52 of a work card 51, which is an IC card connected via an I/F interface device 50. The schedule data input into the schedule input unit 31 is recorded as an operating condition in the database 32.

The schedule data for each train on the line is managed at an operation control center 41. The schedule data is notified via lines of communication to a station controller 42 on the line of the train T. The station controller 42 notifies the schedule data of the train T, as notified from the operation control center 41, by wireless communication to the communication device 40 on the train T, or by writing to the memory unit 52 of the work card 51, which is inserted to the I/F interface device 50 at the beginning of operation by the operator to the train T.

The communication device 40 performs a wireless communication with the station controller 42 and receives a GPS signal. The communication device 40 receives the schedule data notified by a wireless communication from the station controller 42 and outputs to the schedule input unit 31. The I/F interface device 50 can be a card reader; the interface device loads the schedule data stored in the memory unit 52 of the work card 51 and outputs to the schedule input unit 31.

The database 32 stores the data required for the operation of the train T such as a condition of the line (inclination, curvature factor and maximum speed, etc.), an operation condition (a target stop position at each station and a schedule data including scheduled arrival or passing time at each station), and a vehicle performance (vehicle operation characteristics such as vehicle body weight, and accelerating and decelerating performance). More specifically, the database 32 can be a hard drive mounted within the train T or an IC card the operator carries. In the case of the IC card, the database 32 can be used by inserting the card into the I/F interface device 50 at the beginning of the operation.

The timing unit 33 has a Real Time Clock (RTC) function to provide the current time. The current time clocked by the timing unit 33 is output to the ATO device 30. The current time clocked by the timing unit 33 is synchronized with the current time, which is referred to when the schedule data is prepared at the operation control center 41. More concretely, the current time is synchronized to the GPS time included in the GPS signal at the operation control center 41 and the train T. The current time can also be synchronized to the operation control center 41 when stopping at the station by wireless communication.

Next, computing of the operating schedule by the ATO device 30 and the operation of the train T according to the computed operating schedule will be described below. FIG. 2 is a flow chart illustrating an example of the operation of the train control device 1 according to the first embodiment.

As shown in FIG. 2, when steps are initiated, the ATO device 30 acquires the current location of the train T, the current time, and the current speed through the speed and location detector 10 and the timing unit 33 (S1). Next, the ATO device 30 determines if there is an operating schedule to the next station (S2). If the train is stopped at the station before departure, or updating of the next station occurs in S14, the ATO device 30 determines that there is no operating schedule, because the operating schedule has not been computed yet. But, if the operating schedule to the next station has been computed and the train is running according to the computed operating schedule, the ATO device 30 determines that there is an operating schedule.

Without an operating schedule, as determined in S2, the ATO device 30 refers to the operating condition stored in the database 32, which has been input from the schedule input unit 31, and acquires the scheduled arrival (passing) time at the next station (S3). The ATO device 30 then computes the target operation time that is obtained by subtracting the current time from the scheduled arrival (passing) time at the next station (S4), and computes the operating schedule based on the condition of the line and the vehicle performance recorded in the database 32 (S5). Thereafter, the ATO device 30 performs an automatic operation according to the computed operating schedule or displays data for manual operation.

FIG. 3 is a conceptual diagram illustrating an operating schedule P. As shown in FIG. 3, the train T is at station ST1 and is headed for station ST2 with the scheduled arrival time of 12:02:30. If the departure time from the station ST1 is 12:00:18, the target operation time between the stations ST1 and ST2 is 0:02:12. The ATO device 30 computes the operating schedule P defining the powering, coasting and braking sections and curves within a range of the maximum speed at the line condition recorded in the database 32 according to a known method that estimates the operation behavior of the train T using a mechanical train model based on vehicle performance, for example, the method described in the JP-A-1992(Heisei 4)-284684, so that the operation time of the operating schedule becomes closer to the target operation time between the stations.

When there is a time lag between the operation time of the operating schedule P and the target operation time following the above computation, in other words, if they cannot be matched due to a slower operation than the operating schedule as may be caused by a delay of the departure or some operation between the stations by the operator despite an effort to match the operation time of the operating schedule P to the target operation time, the ATO device 30 notifies the operator by displaying a warning on the display device 60, to indicate that the train will not arrive at the next station on time. More specifically, a delay time showing the delay with respect to the operation time of the operating schedule P, and the scheduled arrival time, will be displayed on the display device 60 to notify the operator. This notification can be performed by a warning sound by a speaker; the notification can be issued to operators other than the train operator, such as the station controller 42 and the operation control center 41, via the communication device 40.

Referring back to FIG. 2, if there is an operating schedule in S2, that is, if the train is running according to the computed operating schedule, the ATO device 30 determines if rescheduling of the operating schedule is required or not (S6). More specifically, when the speed of the train T detected by the speed and location detector 10 or the time indicated by the timing unit 33 is out of alignment with the operating schedule by more than a threshold; when the signal indication speed (speed limit) is changed in the analog ATC; or upon achieving a sufficient gap with the preceding train after coming close to the preceding train and reducing the speed, rescheduling is determined to be required. If there is not a sufficient gap with the preceding train after coming close to the preceding train and reducing the speed, rescheduling is not required because the decelerating control (S11), which does not depend on the operating schedule, will be performed. For example, when the signal indication speed notified by the on-board ATC device 20 increases to indicate that the gap with the preceding train has expanded, and a predetermined time has passed after that speed matches the maximum speed at the current running location of the line, the ATO device 30 determines that there is a sufficient gap with the preceding train and that a rescheduling is required.

When rescheduling is required in S6, as similar to S4 and S5, the ATO device 30 computes the target operation time that is obtained by subtracting the current time, at which rescheduling is performed, from the scheduled arrival (passing) time at the next station (S7), and computes the operating schedule based on the target operation time, and the condition of the line and the vehicle performance stored in the database 32 (S8). Consequently, the ATO device 30 performs an automatic operation or a manual operation according to the operating schedule as recomputed. Therefore, even after coming closer to the preceding train between stations, for example, if the gap with the preceding train becomes sufficient thereafter, an operation without a lag from the schedule can be maintained because a new operating schedule is computed.

Next, when running according to the operating schedule, the ATO device 30 determines if it is coming closer to a preceding train or not (S9). More specifically, the ATO device 30 compares the maximum speed at the condition of the line at the current running location and the signal indication speed notified from the on-board ATC device 20; the device determines that it is coming closer to a preceding train if there is a reduction of the signal indication speed. If the signal indication speed increases and a predetermined time has passed after the signal indication speed matches the maximum speed at the condition of the line, the ATO device 30 determines that there is a sufficient gap with the preceding train.

When there is a sufficient gap with the preceding train in S9 (including the case when there is no preceding train), the ATO device 30 continues the operation according to the operating schedule (S10). When coming closer to the preceding train in S9, the ATO device 30 performs the decelerating control so as to achieve a sufficient gap with the preceding train (S11).

Following from S10 and S11, the ATO device 30 determines if the next station is a non-stop station or not (next station=non-stop station?) (S12). If the next station is a non-stop station in S12 (next station=non-stop station), the ATO device 30 determines if the train T has come close enough to the next station (non-stop station) based on the speed and location information from the speed and location detector 10 (S13). Regarding the approach of the train to the next station (non-stop station), it shall be determined whether the train T has come within a predetermined distance to the next station (non-stop station); more specifically, the train has come close enough when the first car of the train T approaches an approaching point of each station (which is defined below). When the train has not yet come close enough to the next station and there is a gap, the ATO device 30 goes back to S1. When it has comes close enough to the next station, the ATO device 30 sets the second next station as the next station (S14).

When the next station is not a non-stop station but a stopping station in S12 (next station =stopping station), the ATO device 30 determines if the train T has arrived at the next station (stopping station) or not based on the speed and location information from the speed and location detector 10 (S15). More specifically, arrival at the stopping station is determined by the approach of the train T at the target stop position of the stopping station. In case of arrival at the next station (stopping station) in S15, the ATO device 30 finishes the process of operation from the departure station to the stopping station. In the case, it has not yet arrived at the next station, the ATO device 30 goes back to S1 and continues the process of operation from the departure station to the stopping station.

FIGS. 4 to 6 are conceptual diagrams illustrating operating schedule P1 to P5 when there are non-stop stations STa to STd. As shown in FIG. 5, when there are non-stop stations STa to STd between the stations ST1 and ST2, the operating schedule P1 to P5 for each non-stop station are computed according to the flowchart described above, and the operation of the train T is performed. The target stop position M1 is a foremost position of the train T when the train T stops at each station, and a base position for the scheduled arrival (passing) time of the train T for each station. The approaching point M2 is a position where the train T has started approaching each station.

More specifically, if the departure time of the station ST1 is 12:00:12 and the scheduled passing time of the non-stop station STa stored in the database 32 is 12:02:15, the operating schedule P1, according to which the train passes the non-stop station STa at a predetermined speed with the target operation time as 0:02:03, is computed. Thus, as shown in FIG. 5, the operation is carried out in accordance with the operating schedule P1 in the range of the target stop position M1 of the station ST1 and the target stop position M1 of the non-stop station STa. Next, the target operation time of the operating schedule P2 based on the time approaching the non-stop station STa (arriving the approaching point M2) and the scheduled passing time of the non-stop station STb 12:04:45, is computed. Thus, as shown in FIG. 6, the operation is carried out in accordance with the operating schedule P2 in the range of the approaching point M2 of the non-stop station STa and the target stop position M1 of the non-stop station STb. Regarding the overlapping section of the operating schedule P1 and the operating schedule P2, the operation according to the operating schedule P1 is implemented until the train arrives the approaching point M2 and the operating schedule P2 is computed, and then switched to the operation according to the operating schedule P2 after operating schedule P2 is computed, so as not to lose the operating schedule. Similarly, operating schedules P3 to P5 of the operation time based on the arrival time at the non-stop stations STb to STd and the scheduled arrival (passing) time at the next station are computed, and an operation in accordance with the operating schedules P3 to P5 is implemented.

As described above, when there are non-stop stations STa to STd in between the stations ST1 and ST2, a hardware resource and load required for computing the operating schedule can be reduced by separately computing operating schedules for every non-stop station. When operating the train T by computing the operating schedule for every non-stop station, even the delay occurs for passing non-stop station, the delay can be canceled while passing the other non-stop station, enabling it to maintain punctuality of the train T.

Second Embodiment

Though the analog ATC is used in the first embodiment described above, a configuration using the digital ATC is described in a second embodiment.

FIG. 7 is a block diagram illustrating a configuration of a train control device la relates to the second embodiment. As shown in FIG. 7, an on-board ATC device 20a receives information from a sideway ATC device 22a through a receiver 21a as a digital signal via the track circuit 23 of the rail R, and then outputs the braking command to the driving and braking control device 3 based on the received information and the speed of the train T. In the digital ATC, the amount of information that the sideway ATC device 22a can notify can be greater than the analog ATC, and the information notified by the sideway ATC device 22a includes the signal indication speed at the closed section where the train T runs in addition to the number of opened block sections. This number of opened block sections denotes the number of closed sections between the closed section where the preceding train runs and the closed section where the train T runs. The on-board ATC device 20 outputs the signal indication speed, which the receiver 21a received, and the number of opened block sections to the ATO device 30.

As similar to the explanation for the first embodiment with reference to FIG. 2, the operating schedule P is computed by the ATO device 30 also in the second embodiment. If the operation time of the computed operating schedule P is longer than the target operation time (when the train is delayed from the target operation time even with a maximum operating schedule), the ATO device 30 adjusts the operating schedule P, within a range up until a “speed braking pattern” of the on-board ATC device 20a is matched, so that the speed of the train T, as it decelerates, comes closer to the speed braking pattern (e.g., by making the braking stronger). As used herein, the “speed braking pattern” corresponds to the speed pattern that is observed when the maximum allowable braking is applied and is estimated by the on-board ATC device 20a based on the speed limit. When the train is estimated to arrive too early when following the operating schedule P (e.g., when the train gained a higher rate of acceleration than expected in the operating schedule P due to the higher voltage of the overhead wire while running), the ATO device 30 adjusts the operating schedule P so as to decelerate the train T earlier (so as to decrease the magnitude of deceleration when decelerating).

FIG. 8 is a conceptual diagram illustrating the relationship of a speed braking pattern BP estimated from the speed limit and the operating schedule P. As shown in FIG. 8, the operating time can be shortened by making the deceleration start position be closer to the speed braking pattern BP and employing an operating schedule Pb which dictates the speed of the train T to follow more closely to the speed braking pattern BP. Also, the operating schedule P can be changed to extend the operation time by employing an operating schedule Pa which dictates the deceleration start position to be earlier as compared to the speed braking pattern BP. The ride quality is improved by a mitigation of rapid deceleration compared to the operating schedule Pb.

The ATO device 30 determines if the gap with the preceding train is sufficient or not when there is a preceding train (FIG. 2, S9) by determining the number of opened block sections and checking if it is more than a predetermined number or not. Thus, the operation having the preferable the gap with the preceding train can be performed.

FIG. 9 is a conceptual diagram illustrating the re-computing of the operating schedule when the gap with a preceding train T1 expands. As shown in FIG. 9, if the train T that is running in accordance with an operating schedule P10 between the station ST1 and ST2 comes closer to the preceding train T1, the train T will decelerate according to the speed braking pattern BP1. Due to train T's deceleration, there will be a greater number of opened block section between the train T and the preceding train T1, and a distance sufficient for not contacting the braking pattern BP1 will be made as the preceding train T1 progresses forward. After keeping the train in lower speed, the ATO device 30 will compute a new operating schedule P20 after the number of opened block sections have become enough to prevent deceleration according to the speed braking pattern BP and continue to operate heading to the station ST2. Therefore, the ATO device 30 can maintain the operation with a smaller deviation from the schedule while maintaining the gap with the preceding train T1

While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiments described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.

Claims

1. A control device for a train, comprising:

a detector configured to detect a current location and a speed of the train;
a clock unit configured to track a current time;
a schedule input section configured to receive an input of schedule data including a scheduled arrival time of the train at each station on a line; and
a computing unit configured to compute an operating schedule according to which the train runs at the detected current location and the detected speed to the next station, based on a target operation time that is obtained by subtracting the current time from a scheduled arrival time at the next station, operation characteristics of the train and a condition of the line.

2. The control device according to claim 1, wherein the train has a speed braking pattern that is determined based on the condition of the line, and the operating schedule is computed so that the speed of the train is adjusted to be closer to the speed braking pattern.

3. The control device according to claim 1, wherein the train has a speed braking pattern that is determined based on the condition of the line, and the operating schedule is computed so that the speed of the train is adjusted to decelerate earlier than specified by the speed braking pattern.

4. The train control device according to claim 1, wherein

the schedule data includes scheduled passing time of the train at non-stop stations on the line; and
when the next station is a non-stop station, the computing unit is configured to compute the operating schedule based on a target operation time that is obtained by subtracting the current time from the scheduled passing time at the next station.

5. The control device according to claim 1, further comprising:

a notification unit that provides a warning when an actual operating time has deviated from the target operation time.

6. The control device according to claim 1, wherein

the computing unit is configured to re-compute the operation schedule after having decelerated to maintain a gap of a predetermined size or larger between the train and a preceding train.

7. The control device according to claim 6, further comprising:

a receiving unit configured to receive a number that indicates the number of closed sections between the train and the preceding train, wherein
the computing unit is configured to re-compute the operating schedule after the received number becomes a predetermined number or more.

8. A method of controlling a train that is scheduled to run on a line having a plurality of stop stations and non-stop stations, comprising:

acquiring a current location and speed of the train, and a current time;
determining a target operation time to a next station by subtracting the current time from a scheduled arrival or passing time at the next station; and
computing an operating schedule for the train based on the target operation time, operation characteristics of the train, and a condition of the line.

9. The method according to claim 8, wherein the condition of the line determines a maximum allowable speed of the train.

10. The method according to claim 9, wherein the maximum allowable speed of the train is set based on a separation gap between the train and a preceding train.

11. The method according to claim 10, wherein the maximum allowable speed of the train is increased when the separation gap increases.

12. The method according to claim 10, wherein the maximum allowable speed of the train is decreased when the separation gap decreases.

13. The method according to claim 9, wherein the maximum allowable speed of the train is set as the maximum speed at which the train can run on the line.

14. The method according to claim 8, wherein a speed braking pattern is associated with the condition of the line and the operating schedule is computed so that the speed of the train is adjusted to be closer to the speed braking pattern.

15. The method according to claim 8, wherein a speed braking pattern is associated with the condition of the line and the operating schedule is computed so that the speed of the train is adjusted to decelerate earlier than specified by the speed braking pattern.

16. The method according to claim 8, further comprising:

decelerating the train;
determining a new target operation time to the next station by subtracting the current time from the scheduled arrival or passing time at the next station; and
re-computing the operation schedule for the train based on the new target operation time, the operation characteristics of the train, and the condition of the line.

17. A train that is scheduled to run on a line having a plurality of stop stations and non-stop stations, comprising:

a driving and braking control device configured to drive and stop the train based on a powering command and a braking command; and
a control device configured to determine a target operation time to a next station by subtracting a current time from a scheduled arrival or passing time at the next station, compute an operating schedule for the train based on the target operation time, operation characteristics of the train, and a condition of the line, and generate the powering command or the braking command according to the operating schedule.

18. The train according to claim 17, further comprising:

a receiver configured to receive a maximum allowable speed of the train from an external device, the maximum allowable speed of the train being representative of a separation gap between the train and a preceding train or a maximum speed at which the train can run on the line.

19. The train according to claim 17, wherein a speed braking pattern is associated with the condition of the line and the operating schedule is computed so that the speed of the train is adjusted to be closer to the speed braking pattern or to decelerate earlier than specified by the speed braking pattern.

20. The train according to claim 17, wherein the control device is further configured to determine a new target operation time to the next station by subtracting the current time from the scheduled arrival or passing time at the next station and re-compute the operation schedule for the train based on the new target operation time, the operation characteristics of the train, and the condition of the line.

Patent History
Publication number: 20130325224
Type: Application
Filed: May 28, 2013
Publication Date: Dec 5, 2013
Applicant: Kabushiki Kaisha Toshiba (Tokyo)
Inventors: Junko YAMAMOTO (Kanagawa), Satoshi Iba (Tokyo), Yasuyuki Miyajima (Tokyo)
Application Number: 13/903,798
Classifications
Current U.S. Class: Railway Vehicle Speed Control (701/20); Railway Vehicle (701/19)
International Classification: B61L 27/00 (20060101);