[0001] The present invention is related to railway vehicle buffers, of the type comprising
a buffer casting intended to be fixed to one headstock of the vehicle and a hollow
buffer stem slidably supported by the buffer casting and carrying a buffer end plate.
[0002] In the railway vehicles the buffer end plate is traditionally fixed rigidly to the
buffer hollow stem and projects from the vehicle headstock permanently, i.e. even
in the case the vehicle is not to be coupled with other railway carriages and the
presence of the buffer is not strictly necessary.
[0003] In the case of buffers applied to the front headstock of a high-speed train, this
constitutes a disturbing element both in connection to the travelling aerodynamic
performances of the train lonely, and as far as the aesthetical profile thereof is
concerned.
[0004] A solution for overcoming the above drawback consists of connecting the buffer end
plate to the buffer stem detachably, so as to allow removal thereof whenever its presence
is not necessary. Disassembly must be carried out manually and therefore, considering
the weight and size of the buffer plate, this operation is uncomfortable and fatiguing,
requires a long working time and involves the need of providing for a suitable store
onboard the vehicle for containing the removed buffer plates.
[0005] Another known solution, particularly suitable for the vehicle front headstock, consists
of employing an auxiliary fairing releasably applied so as to cover the buffers. Even
this solution is however unpractical and has the same drawbacks, as far as the applications
and removal operations of the auxiliary fairing are concerned, previously mentioned
in connection with the detachable buffer plates.
[0006] It has also been proposed to connect the whole buffer to the vehicle structure in
a swingable way, i.e. such to allow complete rotation thereof into a position sustantially
parallel to the vehicle headstock. This solution involves problems of encumbrance
of the buffers in the rotated condition, and above all completely suppresses the protective
action of elastic absorbtion thereof in case of accidental collision of the vehicle.
[0007] The object of the present invention is to provide a buffer of the type defined at
the beginning, which is adapted to take, in a constructively simple and functional
way, starting from the normal working position, a rest position in which it does not
negatively affect the aerodynamic characteristics of the vehicle on which it is applied,
in the same time safeguarding its elastic absorbtion effectiveness in the case of
accidental collision.
[0008] According to the invention, this object is achieved by virtue of a railway vehicle
buffer of the above-specified type, the main feature of which resides in that the
buffer end plate is connected to the buffer stem rotatably between an extended working
position and a retracted rest position.
[0009] According to a preferred embodiment of the invention, the connection between the
buffer plate and the buffer stem comprises a pair of studs of which one defines the
axis of rotation of the buffer plate between the said extended and retracted position,
and the other is constituted by a releasable latch.
[0010] Preferably but not necessarily, the axis of rotation of the buffer plate is vertical,
whereby in the retracted position the buffer end plate is positioned aside the buffer
casting-stem assembly.
[0011] Displacement of the buffer end plate from the extended working position to the retracted
rest position, and viceversa, can be comfortably operated manually, or alternatively
suitable servomechanism can be provided for.
[0012] The advantages deriving from the configuration of the buffer according to the invention
are essentially as follows:
- adaptation of the railway vehicle headstocks (and in particular the front headstock)
to the aerodynamic needs of travel of the vehicle alone;
- easy convertibility from the working position to the rest position, and viceversa,
without any need of transfering by hand the buffer end plate;
- absence of large fairings to be removed from the headstock fairing of the vehicle
in case of coupling with other railway carriages;
- buffer always ready to protect the vehicle in case of any accidental collision.
[0013] The invention is further related to a high-speed railway vehicle provided with buffers
according to the above, applied in correspondence of at least one headstock thereof
provided with an aerodynamic fairing. The vehicle according to the invention is mainly
characterized in that the said fairing is provided, in frontal correspondence of each
buffer, with movable sections adapted to be removed so as to allow projection of the
buffer plate outwardly in the extended working position, and to be re-applied when
the buffer plate is returned in the retracted position within the fairing.
[0014] The invention will now be described in detail with reference to the annexed drawings,
provided purely by way of non limiting example, wherein:
figure 1 is a diagrammatic perspective view of a portion of a railway vehicle provided
with a pair of buffers according to the invention, shown in the extended working position,
figure 2 is a horizontally sectioned view in an enlarged scale along line II-II of
figure 1,
figure 3 is a vertical sectioned view in an enlarged scale along line III-III of figure
2, and
figure 4 is a view similar to figure 1, with the buffers shown in the retracted rest
position.
[0015] Referring initially to figure 1, reference T designates the front headstock of a
high-speed railway vehicle, provided with an aerodynamic fairing C formed inferiorly
with two openings A through each of which a buffer end plate of a respective buffer
2 projects outwardly.
[0016] As it is shown in better detail in figure 2, each buffer 2 comprises, in a way generally
known per se, a buffer casting 3 provided with a connecting flange 4 for the rigid
fixing to the structure of the headstock T, and a hollow buffer stem 5 carrying the
buffer end plate 1 and slidably supported by the buffer casting 3. Axial backing of
the buffer stem 5 (and thus of the buffer end plate 1) relative to the buffer casting
3 enables, as it is known, absorbtion of frontal impacts possibly transmitted during
travelling by a railway carriage coupled ahead of the headstock T, or during manoeuvres
of the vehicle. To such extent a conventional elastic dissipator system, not shown
in the drawings, is interposed between the buffer stem 5 and the buffer casting 3,
within the latter.
[0017] According to the invention, the buffer end plate 1 is not connected rigidly to the
free end of the buffer stem 5, but rotatably between an extended working position,
shown in figure 1 and with dotted lines in figure 2, and a retracted or folded rest
position, shown with dotted lines in figure 2 and in figure 4.
[0018] As it can be better seen in figure 3, the structure of the buffer end plate 1 incorporates
internally an upper plate 6 and a lower plate 7 between which a support body 8, mounted
in the teminal portion 9 of the buffer stem 5, is inserted.
[0019] The connection between the two plates 6, 7 of the buffer plate 1 and the support
body 8 of the buffer stem 5 is performed, in the case of the shown example, by means
of a pair of verticals studs 10, 11 placed side by side and inserted through corresponding
holes 6a, 7a, 8a and 6b, 7b and 8b of the plates 6, 7 and of the body 8, respectively.
[0020] The stud 10 is fixed, and the axis X thereof defines the pivot axis of the buffer
plate 1 between the extended and the retracted positions.
[0021] The stud 11 defines on the other hand a relasable latch, and to such extent it is
provided at its upper end with a grip eye 12 and at its lower end with a radial stop
pin 13, which can be pulled out in order to allow extraction upwardly of said stud
11.
[0022] In the extended working position the buffer plate 1 is placed on the prolongation
of the buffer stem 5, with the stud 11 inserted through the holes 6b, 7b of the two
plates 6 and through the hole 8b of the support body 8, and is projecting in front
of the fairing C of the headstock T through the corresponding opening A. In such a
position the buffer plate is able to receive and transmit to the buffer 2 any possible
front impact.
[0023] In order to shift the buffer plate 1 into the retracted rest position it is sufficient
to remove the stop pin 13 and withdraw the stud 11, acting on the grip eye 12, and
then push the said buffer plate 1 inwardly with respect to the fairing C, rotating
same around the axis X of the stud 10, so as to position it aside the buffer 2, such
as shown in figure 2. This operation can be carried out manually, in an extremely
easy way and with a minimum effort, or alternatively with the aid of servomechanisms
(not shown since within the knowledge of the man skilled in the art), constituted
for instance by electric or fluid pressure actuators.
[0024] In the retracted position the buffer plate 1 is fully housed within the fairing C
and the relative opening A can be advantegeously closed by applying a movable section
S which completes the aerodynamic profile of the fairing C and is detachably secured
thereto by any suitable means, such as screw locking members or the like.
[0025] In order to position again the buffer end plate 1 in the extended working condition
it is simply necessary, after removing the movable section S, rotating same towards
the starting position around the axis X and then inserting and locking the stud 11.
Also this operation can evidently be carried out either by hand or by means of a servomechanism.
[0026] It is to be pointed out that, also in the retracted rest position of the buffer plate
1, the buffer 2 is in any case able to protect the railway vehicle from possible accidental
collisions, through the push applied through the fairing C to the end 9 of the buffer
stem 5.
[0027] Naturally the details of construction and the embodiments can be widely varied with
respect to what has been disclosed and illustrated, without thereby departing from
the scope of the present invention.
[0028] Thus for instance, the axis of rotation X of the buffer plate 1 could be placed differently
from the vertical direction, i.e. could be oriented horizontally or even oliquely.
1. Buffer (2) for railway vehicles, comprising a buffer casting (3) adapted to be fixed
to one headstock (T) of the vehicle and a buffer hollow stem (5) slidably supported
by the buffer casting (3) and carrying a buffer end plate (1), characterized in that the buffer end plate (1) is connected to the buffer stem (5) of the buffer (2) rotatably
between an extended working position and a retracted rest position.
2. Buffer according to claim 1, characterized in that the connection between the buffer end plate (1) and the buffer stem (5) comprises
a pair of studs (10, 11) one of which defines the axis of rotation (X) of the buffer
plate (1) between the said extended and retracted positions, and the other is constituted
by a releasable latch (11).
3. Buffer according to claim 2, characterized in that the said axis of rotation (X) of the buffer end plate (1) is oriented vertically.
4. Buffer according to any of the preceding claims, characterized in that it is provided with servomechanisms for operating the buffer end plate (1) between
the said extended and retracted positions.
5. Railway vehicle, particularly a high-speed railway vehicle, characterized in that it is provided with a pair of buffers (2) according to any of the preceding claims
applied in correspondence of at least one headstock (T) thereof.
6. Railway vehicle according yo claim 5, wherein the headstock (T) is provided with an
aerodynamic fairing (C), characterized in that the said fairing (C) is provided, in frontal correspondence of each buffer (2), with
a movable section (S) adapted to be removed so as to allow projecting outwardly of
the buffer end plate (1) of the buffer (2) in the extended working position, and to
be again applied when the buffer plate (1) is shifted into the retracted position
within the said fairing (C).