[0001] The invention relates to a point machine for moving a railway point, comprising at
least one main rod that moves the railway point, at least one detector rod that is
connected to the railway point and follows the movement of the railway point, and
at least one locking device that can lock the movement of the detector rod in at least
one predetermined locking position of the railway point.
[0002] Further, the invention relates to a method for operating a point machine, comprising
at least one main rod that moves the railway point, at least one detector rod that
is connected to the railway point and follows the movement of the railway point, and
at least one locking device that can lock the movement of the detector rod in predetermined
end positions of the railway point, the method comprises the following step: moving
the railway point via the main rod.
[0003] Such devices and methods are known from prior art and are used to move a railway
point to its different positions. The point machine moves a switch blade of the railway
point to its different end positions. The main rod is connected to the switch blade
and moved by a driving motor of the point machine. The detector rod allows point machines
to confirm that they are in their end position. The locking device locks the movement
of the detector rod in the end positions. Therefore, the end positions are also called
locking positions. There are gaps in the detector rod where the locking device fits
in and locks the movement of the detector rod mechanically. Although the gaps in the
detector rod are wider than the locking device, sometimes the position of the gap
of the detector rod and the locking device does not fit and therefore the point machine
cannot be locked. The reason for this can be different and is not completely known.
In this case, the point machine reports a failure as it is not secured that its end
position has been reached. Such failures stop the train traffic until maintenance
has been done to the point machine and the locking device works properly.
[0004] Therefore, it is the purpose of the present invention to provide a point machine
and the method of the above-mentioned type in order to reduce the number of failures
in operation.
[0005] The problem is solved by the subject matter of the independent patent claims.
[0006] The invented solution has the advantage that it is very simple to install and therefore
is not very cost effective. By measuring the position of the detector rod in the longitudinal
direction, it is possible to detect a displacement of the detector rod relative to
a reference position i.e., to the locking device. The reference position can for example
be determined in an installation phase of the point machine and represents the position
where the locking device fits in the gap in the detector rod and where the operation
of the locking device is guaranteed. By implementing the sensor device, it is possible
to detect very early if a displacement relative to the reference position is happening.
A small displacement does not mean a failure of the point immediately, because usually
there is a small clearance. The clearance is made by design and is for example 2.5
mm. If the displacement above a predetermined amount is detected, further additional
action can be done. For example, a maintenance technician can be sent to the point
machine and readjust the setting of the detector rod. During this maintenance work,
the adjustment can be done more easily with the invention because the actual positioning
of the detector rod can be seen permanently by the help of the first sensor device.
Thus, an easy maintenance is possible.
[0007] The invention can be extended by the following advantageous embodiments.
[0008] In one embodiment, the first sensor device may comprise at least one linear encoder.
This has the advantage that the position of the detector rod is available immediately
also after restart of the sensor device and/or the point machine. Therefore, it is
possible to switch off the point machine and the sensor device while it is not in
use.
[0009] In another embodiment, the at least one detector rod comprises at least one adjustment
device, which allows an adjustment of the length of the detector rod in the longitudinal
direction. This has the advantage that a displacement of the detector rod can be maintained
very quickly and easily. The adjustment device can for example be designed very simple
as a clutch with an adjuster nut and lock nut, so that the distance of the clutch
parts can be regulated by the adjuster nut.
[0010] Further, in order to transfer the measured data to a separate device or database,
the point machine comprises at least one communication device, which can communicate
data with an external device.
[0011] In another advantageous embodiment, the point machine comprises at least one second
sensor device, which measures an ambient temperature. This has the advantage that
also the temperature is monitored. The temperature can influence the material of the
detector rod and, therefore, its length. So it is useful to take this into account.
[0012] In another embodiment, the point machine comprises at least one evaluation device,
which is connected to the first sensor device and is designed to evaluate the measured
position of the detector rod relative to a reference position. This has the advantage
that findings out of the measurements can be evaluated automatically. For example,
the evaluation device is designed to evaluate a maintenance plan using the measured
position, wherein the maintenance plan for example includes work instructions for
adjusting the length of the detector rod. This has the advantage that a much faster
maintenance is possible. Maintenance work on railway points has very often a lot of
time pressure. Therefore, faster maintenance is very useful. The maintenance plan
can for example include instruction how many rotations of an adjuster nut in which
direction are needed. Therefore, the maintenance worker can work faster and more accurate.
[0013] In an embodiment of the inventive method, an ambient temperature of the point machine
can be measured by a second sensor device. This has the already further above-mentioned
advantage that the temperature can be considered as the temperature can have an influence.
[0014] In another embodiment, evaluating a maintenance plan using the measured position,
wherein the maintenance plan includes work instructions for adjusting the length of
the detector rod. This has the already above-mentioned advantage that the maintenance
work can be accelerated.
[0015] Finally, the invention further relates to a computer program product, comprising
instructions for performing the method of the above-mentioned embodiments.
[0016] In the following, the invention will be further described related to the exemplary
embodiment in the attached drawings.
[0017] It shows:
- Fig. 1
- schematic drawing of an exemplary embodiment of a point machine according to the invention;
- Fig. 2
- schematic detailed drawing of the point machine of fig. 1;
- Fig. 3
- a schematic drawing of the point machine of fig. 2 with additional details;
- Fig. 4
- a side view of fig. 3.
[0018] In the following, the invention is described related to the exemplary embodiment
in fig. 1 to fig. 4.
[0019] A railway facility 1 comprises railway tracks with railway points 2, one of these
railway points 2 is shown in fig. 1. This railway point 2 comprises a point machine
3, stock rails 4, and point blades 5, wherein the point machine 3 moves the point
blades 5 between the stock rails 4.
[0020] The point machine 3 comprises a housing 6, a drive motor 7, a main rod 8, and 2 detector
rods 9. The main rod 8 is connected to the point blades 5 and driven by the drive
motor 7 via a gear box 10. So, the main rod 8 is driven in a longitudinal direction
11 by the drive motor 7 to move the point blades 5 between its end positions. In each
of the two end positions, one of the two point blades 5 is adjacent to one of the
stock rails 4 in a well-known manner. Therefore, in the end positions a safe movement
of the trains over the point is possible.
[0021] The detector rods 9 are respectively connected to one of the point blades 5 and follow
their movement. Therefore, by the detector rods 9 the position of the point blades
5 can be detected. Within the housing 6 of the point machine 3 there are two locking
devices 12. The locking devices 12 respectively fit into gaps 13 in the detector rods
9. If the point blades 5 are in one of their end positions, the gap 13 is aligned
with the locking device 12, and the locking device 12 is moved in a direction rectangular
to the longitudinal direction 11 so that the detector rod 9 is mechanically locked.
[0022] The point machine 3 according to the invention further comprises first sensor devices
15. Each first sensor device 15 comprises at least one absolute linear encoder 16
that is fixed to the housing 6 and one magnetic slider 17 that is connected to the
detector rod 9. By the sensor device 15 each movement of the detector rod 9 can be
measured. To integrate the magnetic slider 17 it could be useful to extended the detector
rods 9 and do some milling at the end to place the magnetic slider 17. It is also
possible to place the first sensor devices 15 on different locations at the different
detector rods 9. This can be advantageous if the space in the housing 6 is limited.
[0023] The point machine 3 according to the invention further comprises a second sensor
device 18. The second sensor device 18 comprises at least one temperature sensor 19
that measures an ambient temperature. In the exemplary embodiment in the figures the
second sensor device 18 is outside the housing 6, but it can alternatively also be
in the housing 6.
[0024] The point machine 3 further comprises an evaluation device 20 that is connected to
the first sensor device 15 and the second sensor device 18. Advantageously, the connection
can be done wirelessly. The evaluation device 20 is designed to evaluate the measured
position of the detector rod relative to a reference position. This has the advantage
that findings out of the measurements can be evaluated automatically. In the exemplary
embodiment of the figures the evaluation device is designed to evaluate a maintenance
plan using the measured position. The maintenance plan includes work instructions
for adjusting the length of the detector rod. This has the advantage that a much faster
maintenance is possible. Maintenance work on railway points has very often a lot of
time pressure. Therefore, faster maintenance is very advantageous.
[0025] Further, every detector rod in the exemplary embodiment of the figures comprises
one adjustment device 24. Each adjustment device 24 allows an adjustment of the length
of the detector rod 9 in the longitudinal direction 11. This has the advantage that
the position of the gap 13 can be changed very quick and easy. The adjustment is done
by rotating a adjuster nut (not shown). A locking nut (not shown) for example locks
the adjustment device 24 after the adjustment. By that it is guaranteed the no unintentional
length change is done.
[0026] The maintenance plan can for example include instructions how many rotations of the
adjuster nut in which direction are needed. Therefore, the maintenance worker can
change the length of the detector rod 9 very quickly. In a future embodiment an automatic
adjustment device could be included or a tool that automatically adjusts the adjustment
device 24 according to the working plan of the evaluation device 20.
[0027] The point machine 3 further comprises a communication device 21 by which data generated
by the evaluation device 20 can be communicated externally. This communication can
for example be to a cloud storage 22. The cloud storage 22 enables a long-term monitoring
of the detector rods 9 generating useful insights on several railway points 2. For
example, it generates a global view on the condition of several point machines 3 that
are equipped with the invention. The data generated by the evaluation device 20 can
be used for predictive maintenance of the point machine 3 and/or the whole railway
facility 1. Further, via the temperature data gathered with the displacement information,
it will be possible to predict the detector rods 9 displacement based on weather forecast.
Finally, with all these information it could be possible to generate a planning for
each technician to send them onsite and thus avoid as much as possible disruptions
on the railway facility 1 while optimizing the schedule of every technician currently
devoted to this task.
[0028] Additionally or alternatively, the point machine 3 may further comprise a local visualization
device 23, by which data or maintenance advice can be shown locally, for example to
a service technician that works on the railway point 2.
[0029] Figure 4 shows a side view of the detector rod 9 with its gap 13 and the locking
device 12 that moves in the gap 13. In the exemplary embodiment of the figures the
gap 13 has a width B in the longitudinal direction 11 of 21 mm. The locking device
12 has a width A in the longitudinal direction of 16 mm. thus, there is a designed
clearance of 2.5 mm on each side of the locking device 12 in theory. However, as already
mentioned during service of the railway point 2 the clearance can change. Due to the
invention these changes do not lead to problems and down time of the railway point
2.
1. Point machine (3) for moving a railway point (2), comprising
at least one main rod (8) that moves the railway point (2), at least one detector
rod (9) that is connected to the railway point (2) and follows the movement of the
railway point (2), and
at least one locking device (12) that can lock the movement of the detector rod (9)
in at least one predetermined locking position of the railway point (2),
characterised in that
the point machine (3) comprises at least one first sensor device (15) which is designed
to measure the position of the at least one detector rod (9) in a longitudinal direction
(11) in the locking position.
2. Point machine (3) according to claim 1,
characterised in that
the first sensor device (15) comprises at least one absolute linear encoder (16).
3. Point machine (3) according to claim 1 or 2,
characterised in that
the at least one detector rod (9) comprises at least one adjustment device (24), which
allows an adjustment of the length of the detector rod (9) in the longitudinal direction
(11) .
4. Point machine (3) according to one of the preceding claims,
characterised in that
the point machine (3) comprises at least one second sensor device (18), which measures
an ambient temperature.
5. Point machine (3) according to one of the preceding claims,
characterised in that
the point machine (3) comprises at least one communication device (21), which can
communicate data with an external device.
6. Point machine (3) according to one of the preceding claims,
characterised in that
the point machine (3) comprises at least one evaluation device (20), which is connected
to the first sensor device (15) and is designed to evaluate the measured position
of the detector rod (9) relative to a reference position.
7. Point machine (3) according to claim 6,
characterised in that
the evaluation device (20) is designed to evaluate a maintenance plan using the measured
position, wherein the maintenance plan includes work instructions for adjusting the
length of the detector rod (9).
8. Method for operating a point machine (3) comprising at least one main rod (8) that
moves the railway point (2), at least one detector rod (9) that is connected to the
railway point (2) and follows the movement of the railway point (2), and
at least one locking device (12) that can lock the movement of the detector rod (9)
in predetermined end positions of the railway point (2),
the method comprises the following steps:
- moving the railway point (2) via the main rod (8),
characterised in that
- measuring the position of the at least one detector rod (9) in a longitudinal direction
(11) in the locking position of the railway point (2) by a first sensor device (15).
9. Method according to claim 8,
characterised in that
measuring an ambient temperature of the point machine (3) by a second sensor device
(18).
10. Method according to claim 8 or 9,
characterised in that
evaluating a maintenance plan using the measured position, wherein the maintenance
plan includes work instructions for adjusting the length of the detector rod (9).
11. Computer program product comprising instructions for performing the method according
to claims 8 to 10.