Note: Descriptions are shown in the official language in which they were submitted.
CA 02354970 2001-08-13
1
SINGLE-AXLE WHEEL SET WITH OUTER SUSPENSION SUPPORTS
FOR RAILWAY VEHICLES WITH PENDULUM-TYPE SUSPENSION
Field of the Invention
The present invention refers to improvements introduced
into the suspension chassis of single-axle wheel sets of
railway vehicles provided with pendulum-type suspension,
comprising a chassis on which independent, movable wheels
are mounted, said chassis having a pendulum-type suspension
system with its suspension springs arranged in the upper
part of upright supporting means.
Previous State of the Art
Until now, single-axle wheel sets of low-floor railway
vehicles with pendulum-type suspension have incorporated a
chassis with a yoke shape in which the vertical suspension
supports were mounted on the wheel area.
This prior art, in relation to which we may mention
Spanish patents Nos. 424615, 454721, 474678 and 527222, is
represented in Fig. 1 of the attached drawings, which
diagrammatically show a suspension system currently used in
railway vehicles of the mentioned type.
Moreover, European patent 0884231, "Single-axle wheel
set with independent movable wheels for articulated car-
transporting wagons", discloses a single-axle wheel set with
a chassis of similar shape to that described in the preamble
of claim 1.
In said Fig. l, a single-axle wheel set chassis of the
known type is generally indicated with 1, with a yoke shape
having end parts 4, 4' in the shape of an inverted U on
which the wheels R are mounted with the corresponding
bearing boxes (not shown) which belong to this type of
single-axle wheel set. The suspension supports 2, 2' are
precisely mounted on said parts 4, 4', each of which
suspension supports ends in its upper part in a shock-
absorbing spring, especially of the pneumatic type 3, 3'.
However, this type of suspension chassis of the prior
art has the drawback that it limits the maximum diaphragm
CA 02354970 2001-08-13
2
passage width between carriages to a size of about 800 mm,
as its frame 5 must be housed between the inner legs 6, 6'
of the yoke-shaped chassis 1 and the suspension supports 2,
2' .
Summary of the Invention
In order to be able to have diaphragm passages of
greater width, so as to facilitate the transit of
passengers between the carriages and, therefore, to offer
them more comfort when they move among the areas accessible
to them inside the train, a new type of single-axle wheel
set has been designed with a suspension system
characterised in that the chassis of said single-axle wheel
set is a flat, horizontal chassis, and in that the
suspension supports are made up of a framework in the form
of a portico, the lower ends of the upright legs of said
portico being attached to said flat chassis at points
situated on the outer part of said wheels and whose upper
crosspiece incorporates shock-absorbing springs close to
its outer ends.
In a preferred embodiment of the invention, the
attachment points of the lower ends of the legs of said
portico are situated directly upon the outer bearing boxes
of each wheel.
In accordance with another preferred embodiment of the
invention, the anchoring of the system of articulated bars
which control the position of the wheel set in relation to
the boxes of the carriages between which said wheel set is
arranged, is in the outer, lower part of the legs of said
portico.
Brief description of the drawings
The single-axle wheel set in accordance with the
invention will now be described in more detail, with
reference to the attached drawings, in which:
Fig. 1 shows, diagrammatically, a suspension system
currently used in railway vehicles of the type to which the
present invention refers; and
Fig. 2 shows, diagrammatically, a suspension system in
CA 02354970 2001-08-13
3
accordance with the present invention.
Detailed description of the preferred embodiments
With reference to the drawings, Fig. 1 of the same, as
already described, diagrammatically represents the general
arrangement of a single-axle wheel set in accordance with
the prior art for railway vehicles with pendulum-type
suspension.
With reference now to Fig. 2, this represents the new
wheel set 10 with a suspension portico in accordance with
the present invention. This wheel set 10 has a flat,
horizontal chassis B, on whose end parts the wheels R are
mounted.
Externally with respect to each one of the wheels R of
said wheel set 10, the lower ends of a framework in the
form of a portico are fixed to the chassis at 40, 40', said
framework being made up of uprights 20, 20' with a
quadrangular cross-section but which, in general, may be of
any shape, whether polygonal or circular, and an upper,
substantially straight horizontal crosspiece 22. Shock-
absorbing springs, especially of the pneumatic type, are
mounted close to the upper end parts of said upper
crosspiece 22. Said springs enable, in a known way, the box
of the carriage thus suspended to adopt the position
required for taking a curve. Finally, 50 indicates the
frame of the diaphragm allowing passengers to move between
carriages.
In accordance with a first preferred embodiment of the
invention, the lower ends of the uprights 20, 20' are
mounted directly upon the bearing boxes which support the
outer end of each independent wheel of the wheel set 10.
In accordance with another preferred embodiment of the
invention, the single-axle wheel set l0 can be provided
with an anchoring for linking to it a system (indicated in
general with the number 60) of articulated wheel set guide
bars for controlling its position in relation to the boxes
of the carriages between which the wheel set 10 is
arranged.
CA 02354970 2001-08-13
4
As may be observed in said Fig 2 of the drawings, this
particular solution will allow a passage diaphragm to be
provided with greater maximum widths than those allowed by
suspension systems of the prior art, reaching about 1200
mm, which is appreciably greater than what is normally
found in railway equipment currently in use and which may
even allow two passengers carrying suitcases to pass each
other as they move between carriages.
Other advantages provided by the new wheel set in
accordance with the present invention are:
- it allows greater auxiliary volume for the
pneumatic suspension springs; and
- the portico-type structure provides the wheel set
unit with greater mechanical strength.
