STATE OF THE ART
[0001] . The train derailment is the phenomenon that occurs when one or more prebuilt wheelset
transverse constraint formed by the flange of wheel and the rail head shall lose;
such an event can cause extensive damage to vehicles, to railway infrastructure, in
particular to the track equipment, to the electric traction and to the signaling installations.
[0002] . Today, modern locomotives, equipped with automatic adjustments for the running, have
available extremely high powers that allow them to tow heavy convoys thus preventing
the driver to realize, in a timely manner, the enhanced tensile strength, due to one
or more wagons astray; the phenomenon of the derailment is not limited to a few hundreds
of meters of damaged infrastructure (the space needed to safely shutdown the convoy
after the perception of the derailment) but also continues to kilometers before the
driver has perception and intervene with rapid braking.
[0003] . It must also be considered the risk related to the prolongation of the derailment
of a wagon progressing inadequately that increases the seriousness of the risk linked
to the welfare of the people, the surroundings, and to rail traffic in general.
[0004] . The idea of being able to quickly assess whether a cart is derailed is not new; already
in the past years several systems have been studied to assess in real time the conditions
of derailment of a train.
[0005] . Among these, the most known is the detection of derailment through the pneumatic
system of a railway vehicle said "EDT 101" of the German company KNOOR-BREMSE of Monaco;
however, to date we are still not fully used to it for the need of having to install
on all freight wagons these systems and this represents a major obstacle to their
use, given the high number of wagons currently circulating in Italy and in Europe.
SCOPE OF THE INVENTION
[0006] . Hence the idea of creating a system that does not need to be installed on all wagons,
but simply on the locomotives only; in this way, it definitely solves the problem
related to the number of vehicles to be equipped of instrumentation, since the number
of locomotives is a small fraction of the total number of circulating railway vehicles;
the system of the present invention can be used on all of the locomotives pulling
hooks towing wagons cargo and / or passenger coaches.
[0007] . The invention object of this application is composed of:
- a) a load cell mounted to the hook of the locomotive to detect in a continuous manner
the tensile stress,
- b) an accelerometer able to recognize the different nature of the effort resulting
from the derailment than the normal running condition specified on the route (acceleration,
braking, uphill, downhill, curves),
- c) a GPS module to geo-reference the convoy at the time of the derailment and calculate
the speed of travel,
- d) an appropriate software that evaluates with an HMI (human machine interface) if
there are any anomalous tensile stresses due to the derailment of one or more wagons,
- e) a module using GSM-R specific for railways (Global System for Mobile Communications
- Railways) for the transmission of data remotely,
- f) an audio and visual alarm in the cab for the driver.
[0008] . The objective to be achieved, with the invention of the present application, is that
to warn the driver that the convoy is in abnormal running conditions or derailment,
so as to minimize the damage to the convoy and to the infrastructure.
DETAILED DESCRIPTION OF THE INVENTION
[0009] . The invention object of the present application is a system composed by several electronic
and electro-mechanics equipment belonging to three separate functional groups:
- a) Measurement equipment (Fig. 1 and 2 - A - B - C - D),
- b) Equipment of first processing and transmission of measurement data (Fig. 1 and
2 - E),
- c) Equipment of final data processing and its registration with issuing of audible
and visual alarm signal, at the recognition of the derailment with possible deployment
in remote data (Fig.1 and 2 - F).
[0010] . Measurement equipment for the traction stress consists of an electro-mechanical sensor
(traction, cut, or bend-type load cell - Fig. 1 and 2 - A) equipped of strain gauges,
installed as an electrical scheme of a double Wheatstone bridge, or by half Wheatstone
bridge or by a quarter of a Wheatstone bridge or by one or more complete Wheatstone
bridge.
[0011] . The apparatus for detection and measurement of the traction stress are preferably
present in number of 2 units for each locomotive (one for each direction of travel).
[0012] . The load cells (Fig.1 and 2 - A) preferably will be mounted on the traction hook
of the sole locomotive and they detect the value of the stress applied to the traction
hook of the entire convoy.
[0013] . The fastening of the load cell method is purely mechanical and is, preferably, for
coupling along the traction rod (Fig. 2 - G).
[0014] . The load cell, suitably powered from the locomotive battery or any other source of
electrical energy, will release a value in mV directly proportional to the variation
of stress to the hook; this voltage, amplified by a signal conditioner (analog or
digital) will be sent to the equipment of first processing and transmission data preferably
by cable or by radio (Fig.1 and 2 - E).
[0015] . In a preferred mode of realization, the load cell is of toroidal geometry and is
mounted in the axis of the traction hook of the locomotive (Fig. 1 and 2 G - A).
[0016] . The first processing and data transmission apparatus (Fig. 1 and 2 - E) communicates
by wire or by radio with the final data processing equipment (Fig. 1 and 2 - F).
[0017] . The accelerometer (Fig. 1 and 2 - B) detects accelerations of the locomotive, at
least along the three Cartesian axes: X, Y and Z.
[0018] . The GPS module (Fig. 1 and 2 - C) detects data related to geographic coordinates,
preferably according to the NMEA 0183 protocol.
[0019] . The mobile module (Fig. 1 and 2 - D), at the end of the journey, transmits by GSM-R
all data recorded along the way.
[0020] . All the installed sensors, in a preferred mode of realization, are electronically
connected to a microprocessor for the first processing and subsequent transmission
of data and, with the exception of the load cell, they are placed in a container,
for example in PVC or metal equipped with connectors for cables and antennas required
for the receipt and transmission of data ().
[0021] . In this preferred mode of realization, the container Fig. 1 and 2 - E) has suitably
shaped holes to allow the fixing of the panel connectors for the wiring of the cables
coming from the sensors (Fig. 1 and 2 - A - B - C - D), and a USB panel connector
to allow the electronic equipment be connected to a PC (Fig. 1 and 2 - F) for the
data transmission operations and for the periodic maintenance of the system.
[0022] . In this preferred mode of realization, the electronic equipment inside the container
(Fig. 1 and 2 - E) include a suitable power supply capable of adequately transforming
the voltage taken from the electrical system of the locomotive or from other power
source for supplying the entire system.
[0023] . The analog signal issued by the load cell is converted into a digital value (numeric
value) and it is sent through a serial communication, via cable to the device of the
final processing of the data, equipped with dedicated software.
[0024] . The final data processing equipment (Fig. 1 and 2 - F) consists of an HMI (human
machine interface) where the dedicated software can process all data received from
the sensors, their parameters, verify and record them.
[0025] . The software, on the basis of the driving conditions, from the magnitude of the variation
of the detected tensile stress to the hook, considering also the duration of the variation
of the stress, and on the basis of the variation of acceleration and speed of the
train, is able to detect anomalous stress trends at the locomotive hook and activate
the alarm with light and sound signaling systems.
[0026] . The software automatically creates an encrypted file for saving input data, process
data and output data that remains available to the infrastructure manager and the
train service manager in the event of subsequent investigations.
[0027] . Once the train service is over, the software sends all data remotely, preferably
by GSM-R specific for railways (Global System for Mobile Communications - Railways)
or by a common mobile phone technology or any other protocol commonly today used for
data transmission over the air.
1. Automatic radio-electro-mechanical system for the detection of the derailment of one
or more railway wagons towed by a locomotive, with an alarm signal in the cabin, comprising:
i) One load cell for each traction hook at the sole locomotive (A) for the measurement
of the stresses within the traction hook,
ii) An accelerometer (B),
iii) A GPS module (C),
iv) A module that uses the GSM-R mobile telephone technology (D) specific for railways
(Global System Communication - Railways) for the transmission of data remotely,
v) A HMI interface (F),
vi) Optical and acoustic alarm devices in the cabin.
2. System according to claim 1 in which the measurement of traction stress takes place
by means of load cells (A) provided with strain gauges installed in the cell preferably
according to the wiring diagram of a double Wheatstone Bridge.
3. System according to claim 2 in which the Wheatstone bridge is selected from one or
more of whole Wheatstone Bridges, a half Wheatstone bridge and a quarter of a Wheatstone
bridge.
4. System according to claims 2-3 wherein the strain gauges, are selected among the following
types: traction and compression, bending, and cut.
5. System according to claims 1-4, further comprising transmitting data from the sensors
(i, ii, iii, iv) to the first processing apparatus (E), and the transmission from
the first processing apparatus to the final processing apparatus (v) (F).
6. System according to claim 5, in which the transmission of data from the first processing
apparatus to the final processing of the apparatus preferably takes place by cable
or by radio, preferably at a selected wavelength between micro wave, short wave, medium
wave and long waves.
7. System according to claims 5-6 wherein the first processing apparatus are amplifiers
or conditioners of analog or digital signal and amplify the signal received from sensors.
8. System according to claim 7, wherein the final processing apparatus running the dedicated
software, that correlates the traction effort to the hook of the locomotive with the
parameters detected by all the other sensors and verifies the condition of the train
being misled, emitting, when necessary, a visual and acoustic alarm signal.