U.S. patent application number 10/422260 was filed with the patent office on 2004-01-29 for level control for a rail-mounted vehicle.
Invention is credited to Schimanofsky, Alexander, Teichmann, Martin, Waltensdorfer, Herwig.
Application Number | 20040016361 10/422260 |
Document ID | / |
Family ID | 30772847 |
Filed Date | 2004-01-29 |
United States Patent
Application |
20040016361 |
Kind Code |
A1 |
Teichmann, Martin ; et
al. |
January 29, 2004 |
Level control for a rail-mounted vehicle
Abstract
The rail vehicle (1) comprises a sub-frame (2) and a wagon body
(3) disposed above it. Between the wagon body (3) and the sub-frame
(2) a spring stage (4) is provided and between the wagon body (3)
and the sub-frame (2) at least one actuator (6) is provided which
is arranged to bring the wagon body (3) from a raised travel
position into a lowered load/unload position against a restoring
force produced by the spring stage (4) to keep it in the
load/unload position. The wagon body (3) is raised into a travel
position by the restoring force upon deactivation of the actuator
(6).
Inventors: |
Teichmann, Martin; (Graz,
AT) ; Waltensdorfer, Herwig; (Graz, AT) ;
Schimanofsky, Alexander; (Wien, AT) |
Correspondence
Address: |
Welsh & Katz, Ltd.
THOMAS R. VIGIL
22nd Floor
120 South Riverside Plaza
Chicago
IL
60606
US
|
Family ID: |
30772847 |
Appl. No.: |
10/422260 |
Filed: |
April 24, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60376057 |
Apr 26, 2002 |
|
|
|
Current U.S.
Class: |
105/164 |
Current CPC
Class: |
B61D 47/00 20130101;
B61F 5/148 20130101 |
Class at
Publication: |
105/164 |
International
Class: |
B61D 001/00 |
Claims
I claim:
1 Rail vehicle (1) with a sub-frame (2) and a wagon body (3)
disposed above it, wherein at least between the wagon body (3) and
the sub-frame (2) at least one spring stage (4) is provided,
characterised in that between the wagon body (3) and the sub-frame
(2) at least one actuator (6, 6') is provided which is arranged to
bring the wagon body (3) from a raised travel position into a
lowered load/unload position against a restoring force produced by
the at least one spring stage (4a, 4b), and to keep it in the
load/unload position, wherein the wagon body (3) is raised into a
travel position by the restoring force upon deactivation or failure
of the actuator (6, 6').
2 Rail vehicle as claimed in claim 1, characterised in that the
movement of the actuator (6, 6') into the load/unload position is
limited by a stop.
3 Rail vehicle as claimed in claim 1 characterised in that it is
arranged to determine the vertical distance between a floor upper
surface (7) of the wagon body (3) and a floor of the station (5),
wherein a control device is provided which is arranged to control
the movement of the actuator (6, 6') into the load/unload position
using the measured vertical distance.
4 Rail vehicle as claimed in claim 1, characterised in that the
actuator (6, 6') is an electrical and/or mechanical actuator.
5 Rail vehicle as claimed in claim 1, characterised in that the
actuator (6, 6') is a hydraulic and/or pneumatic actuator.
6 Rail vehicle as claimed in claim 1, characterised in that the
spring stage (4a, 4b) has at least one fail-safe passive
spring.
7 Rail vehicle as claimed in claim 6, characterised in that the at
least one fail-safe passive spring is formed as a steel or rubber
spring.
8 Rail vehicle as claimed in claim 1, characterised in that the
spring stage (4a, 4b) is a primary and/or secondary spring stage of
the rail vehicle (1).
9 Rail vehicle as claimed in claim 1, characterised in that the
actuator (6, 6') is formed as a vertical damper of the rail
vehicle.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from provisional
application No. 60/376,057 filed Apr. 26, 2002.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a rail vehicle with a sub-frame and
a wagon body disposed above it, wherein at least between the wagon
body and the sub-frame at least one spring stage is provided.
[0004] 2. Description of the Related Art
[0005] In rail vehicles of the above-mentioned type it can be the
case that when entering into a station the level of the floor in
the wagon body comes to lie higher than the floor level of the
station. By reason of the difference in level between the station
and the upper surface of the floor of the wagon body a step may be
formed in the transition region between the rail vehicle and the
station.
[0006] Especially in rail vehicles which serve to transport people,
these steps can constitute a considerable safety risk for
passengers, for which reason a level adjustment may be carried out.
To this end, the wagon body is normally lowered by reducing the
dynamic spring travel in an active spring disposed between the
wagon body and the sub-frame. However, the reduction in the dynamic
spring travel of the active spring has the inherent risk that if
the level adjustment arrangement fails, there will no longer be
sufficient dynamic spring travel to ensure safe travel operation.
In the event of a failure in conventional level adjustment
arrangements, travel operation is therefore no longer possible. In
order to avoid the problem just mentioned, some known level
adjustment arrangements for rail vehicles have a passive emergency
spring in addition to the active spring, which emergency spring
should ensure sufficient resilience in the wagon body if the active
spring fails.
[0007] A rail vehicle of this type is disclosed by, for example DE
198 15 197 C1. The known rail vehicle has a support actuator which
can be altered in length in the vertical direction and is disposed
between a wagon body and a sub-frame. An emergency spring is
disposed concentrically to the support actuator in order to keep
the support device operating with sufficient travel comfort if the
support actuator fails or is overloaded.
[0008] A rail vehicle of the type mentioned in the introduction is
disclosed, for example in WO94/22702 A1. The known rail vehicle has
a hydraulic spring leg which is disposed between the wagon body and
the sub-frame. In order to lower the wagon body, the dynamic spring
travel of the active spring leg can be reduced by draining oil in a
spring chamber. In the event of a loss of pressure, the vehicle can
be lowered onto an emergency spring as is also known from DE 198 15
197 C1. A disadvantage with this design is, as in all other known
level adjustment systems which also use an emergency spring in
addition to an active spring, that the spring travel of the active
spring is limited "downwards" in the direction of the sub-frame by
the emergency spring, for which reason it may be the case that it
is not possible to lower the wagon body all the way to the floor
level of a station, for example when people are getting on and
off.
BRIEF SUMMARY OF THE INVENTION
[0009] It is therefore an object of the invention to create a rail
vehicle with which it is possible to ensure both safe entry and
exit of passengers in the region of a station and also level
adjustment which is not critically affected by a failure.
[0010] This object is achieved in accordance with the invention
with a rail vehicle of the type mentioned in the introduction in
that between the wagon body and the sub-frame at least one actuator
is provided which is arranged to bring the wagon body from a raised
travel position into a lowered load/unload position against a
restoring force produced by the spring stage, and to keep it in the
load/unload position, wherein the wagon body is raised into a
travel position by the restoring force upon deactivation or failure
of the actuator.
[0011] By means of the solution in accordance with the invention
the vertical distance between the wagon body and the sub-frame can
be varied within a large band width in a stationary rail vehicle.
In the invention, the spring stage disposed between the wagon body
and sub-frame can be compressed by the actuator and the wagon body
can therefore be lowered to a desired level. The wagon body can be
returned to the travel position by a restoring force, which is
produced by the spring stage, by release of the actuator.
[0012] The movement of the actuator into the load/unload position
can advantageously be limited by a stop.
[0013] Furthermore, the rail vehicle can be arranged to measure the
vertical distance between the upper surface of a floor of the wagon
body and a floor of the station, wherein a control device can be
provided which is arranged to control the movement of the actuator
into the load/unload position using the measured vertical
distance.
[0014] The actuator can be hydraulic, electrical, mechanical or
pneumatic in nature.
[0015] Furthermore, the spring stage can comprises [sic] at least
one fail-safe passive spring, wherein this spring can be formed as
a steel or rubber spring. The spring stage is advantageously a
primary and/or secondary spring stage of the rail vehicle.
[0016] Furthermore, when the actuator is hydraulic, the actuator
can also be formed as a vertical damper of the rail vehicle.
[0017] The invention with all further advantages is explained in
more detail hereinunder with the aid of a number of non-limiting
exemplified embodiments which are illustrated in the attached
drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0018] FIG. 1 illustrates a frontal view of a first embodiment of a
rail vehicle in accordance with the invention with a wagon body in
a travel position;
[0019] FIG. 2 illustrates a frontal view of the rail vehicle of
FIG. 1 with a wagon body in a load/unload position;
[0020] FIG. 3 illustrates a frontal view of a partial section of a
second embodiment of a rail vehicle in accordance with the
invention with a wagon body in a travel position;
[0021] FIG. 4 illustrates a frontal view of a partial section of a
third embodiment of a rail vehicle in accordance with the
invention;
[0022] FIG. 5 illustrates a frontal view of a partial section of a
fourth embodiment of a rail vehicle in accordance with the
invention;
[0023] FIG. 6 illustrates a frontal view of a partial section of a
fifth embodiment of a rail vehicle in accordance with the
invention;
[0024] FIG. 7 illustrates a frontal view of a partial section of a
sixth embodiment of a rail vehicle in accordance with the
invention;
[0025] FIG. 8 illustrates a frontal view of a partial section of a
seventh embodiment of a rail vehicle in accordance with the
invention;
[0026] FIG. 9 illustrates an exemplified embodiment of an
actuator.
DETAILED DESCRIPTION OF THE INVENTION
[0027] In accordance with FIGS. 1 and 2 a rail vehicle 1 in
accordance with the invention has a sub-frame 2 and a wagon body 3.
Between the wagon body 3 and the sub-frame 2 at least one spring
stage 4a, 4b is disposed. The spring stage 4a, 4b can be a primary
4a and/or secondary spring stage 4b depending on the construction
type of the rail vehicle 1. Furthermore, the spring stage 4b can be
formed in a manner known per se as an active hydraulic spring,
pneumatic spring etc., wherein, however, at least one further
passive spring 4' is provided.
[0028] During a halt in a station 5, one or a plurality of
actuators 6, 6' can be used to draw the wagon body 3 towards the
sub-frame 2 into a load/unload position, as shown in FIG. 2,
against a restoring force which is produced by the spring stage 4b,
in which load/unload position the level of a floor upper surface 7
of a floor extending in the wagon body 3 lies approximately at the
level of the footway of the station 5. The restoring force is then
produced by the passive spring 4'.
[0029] The actuator 6, 6' can be, for example hydraulic,
electrical, mechanical or pneumatic in nature. The actuator 6 or
actuators 6, 6' can be arranged on the rail vehicle 1 under
consideration of the respective structural or constructional
properties of the rail vehicle 1 so that retrofitting of existing
rail vehicles 1 is possible. In the case of a hydraulic actuator
the actuator or actuators 6, 6' can also be formed as vertical
dampers on the rail vehicle 1.
[0030] When the suspension 4b has an active spring this spring can
be made to act as a passive spring. For example, in the case of an
active hydraulic spring the behaviour of a passive spring can be
forced by non-drainage of oil during its compression. If the spring
stage 4b is purely passive the wagon body 3 is lowered in the
station 5 substantially only by the actuator 6, 6'.
[0031] However, it is also possible to lower the wagon body level
in a manner which is known per se, for example by oil draining of
an active spring, wherein the actuator 6, 6' in this case only
becomes active when the wagon body 3 sits on a passive emergency
spring and the level of the floor upper surface 7 still lies above
the station level. In this case the actuator 6, 6' draws the wagon
body 3 towards the sub-frame 2 against the restoring force of the
emergency spring. The passive emergency spring is therefore
compressed beyond its fixedly set "travel expansion" which normally
cannot be passed statically. Upon release of the actuator 6, 6' the
emergency spring can expand again and lift the wagon body 3 into a
permissible travel position. The passive emergency spring is
preferably formed as a rubber and/or steel spring.
[0032] If the suspension 4b behaves in an exclusively passive
manner during lowering of the wagon body 3, the difference in the
state of the suspension 4b between the load/unload position and the
travel position is merely that in the load/unload state the
suspension 4b is pre tensioned with respect to the travel position
by the actuator 6, 6'. Therefore in a position which is lowered
with respect to a travel position illustrated in FIG. 1 a restoring
force acts upon the wagon body 3 in the direction of the
permissible travel position.
[0033] In the case of passive suspension 4b the restoring force
changes in dependence upon the deflection of the actuator 6, 6'. By
means of the association between the restoring force and actuator
deflection it is ensured that, as already described above in the
event of a failure in the actuator 6, 6', the wagon body 3 can be
returned to the starting position, ie. to the travel position. By
means of the solution in accordance with the invention safe travel
operation is ensured even if the level adjustment arrangement
fails.
[0034] Upon release of the actuator 6, 6' the wagon body 3 is
raised to the travel position by the suspension 4b. If the actuator
6, 6' fails when the wagon body 3 is in the lowered position, the
wagon body 3 is raised to the travel position. In contrast to the
known level adjusters, the wagon body 3, in this embodiment of the
invention, therefore does not fall "downwards" towards the
sub-frame 2 in the event of a failure in the level adjustment
arrangement or in the actuator 6, 6', as already mentioned in the
introduction, but moves "upwards" into the travel position.
[0035] The actuator 6, 6' is preferably in a "non-powered" state in
travel so that substantially no forces produced by the actuator 6,
6' and directed towards the sub-frame 2 act upon the wagon body 3.
However, in principle it is possible for low forces to be exerted
on the wagon body 3 by the actuator 6, 6' during a journey ie. in
travel.
[0036] In order to limit the movement of the actuator 6, 6' into
the load/unload position a fixed stop (not shown herein) can be
provided for the actuator 6, 6'. This embodiment of the invention
is especially advantageous when all stations 5 on a line travelled
by the vehicle 1 are at substantially the same level with respect
to the level of the track.
[0037] On the other hand, if the level of the stations 5 varies,
the rail vehicle 1 can be arranged to determine the vertical
distance between the floor upper surface 7 of the wagon body 3 and
a floor of a station 5, wherein a control device, for example an
appropriate microcomputer, can be provided which is arranged to
control the movement of the actuator 6, 6' into the load/unload
position with the aid of the measured vertical distance.
[0038] In accordance with FIG. 3 each passive spring 4, 4' can be
assigned to an actuator 6, 6', wherein each actuator 6, 6' can be
disposed besides the respective spring 6, 6'. In order to limit the
movement of the wagon body 3 towards the sub frame, each spring 4,
4' can comprise a stop 4f, 4f' made of rubber. Each of the springs
4, 4' can comprise two spring discs 4e, 4e', between which a coil
spring 4c is disposed. Further a rubber-layer spring 4d can be
disposed between the sub frame 2 and the spring disc 4e' near to
the sub frame 2.
[0039] The actuator 6, 6' can also be disposed inside the
respective spring 4, 4' as shown in FIG. 4. Further the
rubber-stops 4f, 4f' can be arranged outside the springs 4, 4'. In
order to limit the movement of the wagon-body 3 towards the sub
frame 2, the wagon body 3 can comprise means 3a, 3a' interacting
with the rubber stops 4f, 4f'.
[0040] According to FIG. 5, the rubber layer spring 4d can also be
disposed between the coil spring 4c and the lower spring 4d disc
4e', so that the rubber layer spring 4d can be expanded by the
actuator 6, 6'.
[0041] In accordance with FIG. 6 the rubber stop 4f", 4f"' and the
actuator 6, 6' can be disposed inside the spring 4, 4'.
[0042] In the embodiment of the invention shown in FIG. 7 the
rubber-stop 4f, 4f' is build around the coil spring 4c.
[0043] According to FIG. 8 the rail vehicle can comprise just one
actuator 6 to bring the wagon body 3 from a raised travel position
into a lowered load/unload position. In the embodiment shown the
primary spring stage 4a and the secondary spring stage 4b can be
tensioned by the actuator 6.
[0044] In accordance with FIG. 9 the actuator 6, 6' can be formed
as a hydraulic actuator 6, 6'. The small arrows show the direction
of distribution of the force in the actuator 6, 6' while the wagon
body 3 is being pulled down into the load/unload position. In
contrast, the large arrow shows the direction of movement of the
wagon body 3.
* * * * *