ES2230052T3 - STOP FOR RAILWAY VEHICLES. - Google Patents

Abstract

The buffer has a buffer casing (1) fixed to the train and an axially moving buffer plunger (2) supported by a spring assembly (13) with a buffer plate (6) arranged on one side of a plunger tube (3). The plunger tube has a radially expanding section (4) on its end facing towards the buffer plate, and the buffer plate is welded to the end of the radially expanding section, to form welds (9) on the inside and the outside of the plunger tube. An Independent claim is included for a method for manufacturing the buffer.

Description

Stop for rail vehicles.

The invention relates to a vehicle stop on rail according to the preamble of claim 1 as well as a a process for its manufacture according to claim 7.

This kind of stops are known in the forms of more diverse realization. While normally the cap presents a sheath of the stop made of one piece, the plunger of the stop It is usually composed of a plunger tube and the saucer cap itself, which is welded at the front end of the piston tube So that the stop, that is, the weld bead Between the top plate and the plunger tube, can withstand high forces and especially also applied forces off center, the stops used so far are provided with a relatively thick wall piston tube and a saucer butt with forged neck and with cord preparations complex welding.

A stop is known from GB 204,659 according to this species for rail vehicles. The top is provided with a stopper sheath to fix the vehicle on track, whose end widens radially towards the top plate. The top plate is provided by its rear face with a recess within which extends the section of the top sheath that It widens radially. The fixation of the butt sheath is performs either by loading under pressure in the recess or by means of a ring that is placed on the inside of the butt sheath, in the area of the section that widens radially.

Starting from a stop made according to Preamble of claim 1, the invention aims at design a stop so that it can be manufactured more economically, in particular by using a tube of thinner wall plunger and a flat top plate without no kind of neck and no preparation of the weld bead, but where the maximum load capacity of the stop is not limited.

This objective is solved by properties indicated in the characteristic of the claim one.

As the piston tube presents by its extreme part, next to the top plate, a section that widens radially towards the top plate, can be reduced its wall thickness and the top plate can be designed very simple, without limiting the load capacity of the stop.  When the top plate is welded to the section that widens radially as proposed in the characteristic of the claim 1, the stresses acting in particular are reduced on the weld seams, which has an influence positive on fatigue resistance of the weld bead. This is due in the first place because of the widening section  radially, the bending stresses that arise can be reduced in case of off-center load. Through the proposed configuration for the plunger tube, it can also be provided in addition to a cord outer peripheral welding, a peripheral welding bead on the inside of the section that widens radially, without this has a negative influence on the maximum guiding length between the plunger tube and the stopper sleeve.

In dependent claims 2 to 6, describe preferred embodiments of the stop.

In claim 7 a further proposed procedure for manufacturing a stop made according to claim 1. Preferred variants of this process are described in dependent claims 8 and 9.

The following is described in greater detail. using a drawing. An example of embodiment of the invention. This sample:

Fig. 1 a longitudinal section through a stop made according to the invention, and

Fig. 2 a longitudinal section through a top, one of whose halves is made according to the state of the technique and the other according to the invention.

Figure 1 describes more fully detail the basic structure of the stop, where essentially only deals in greater detail on the relevant parties in relation to the invention. The top has a top 1 sheath to fix the rail vehicle (not shown) and a piston of the stop 2. The piston of stop 2 is guided axially movable in the stopper sheath 1, which is radially surrounded by the plunger of the stop 2. Both the sheath of the stop 1 and the plunger of the stop 2 they are made essentially with a hollow cylindrical shape, the piston of the stopper 2 consisting of a piston tube 3 and a top plate 6 welded to it. The top 6 saucer made as a cast, forged or folded piece, it has a plate base 6a on whose front face a plate of wear 7 of plastic material.

The plunger of the stopper 2 is supported by a prestressed spring pack 13 in the stopper sheath 1, such so that it can move in the direction of the stopper sheath 1, overcoming the force of the pier. To support the spring package 13 in the sheath of the stop 1, the latter is provided by the face inside of an eyelash 18 while the spring pack 13 sits on the other side on the back side of the motherboard 6a. In the exit direction, the maximum stroke of the stopper piston 2 is limited by an elastic ring 14 that acts as an end stop. To reduce friction between the sheath of the stop 1 and the plunger from the stop 2, plastic elements 16 are provided Annularly. To guide the spring package 13, it is planned a guide pin 12 that is fixed in a recess 11 of the base plate 6a.

The piston tube 3, made of a single piece, get the desired shape preferably by cold plastic deformation. As a starting piece for the tube of the piston 3 a piece of tube is used whose diameter is smaller than the expected final diameter of the stopper sheath 1. In this piece tubular a widening tool is introduced (not shown) provided with a conical section, making it pass through that the piston tube 3 widens to the inside diameter wanted. How this kind of widening tools are basically known it is not necessary to enter here in greater detail about them. Once the tubular part has been widened to Desired diameter is generated in an extreme area of the tubular part, preferably also by cold plastic deformation, the section 4 that widens radially, for which it is pushed inside of the pusher tube 3 a piece of shape (not shown), equipped with the corresponding section.

To ensure a secure connection between the plate base 6 and the piston tube 3 are provided both by the face inside as per the outer face of section 4, which widens radially, two peripheral welding cords 9, 10. The proposed configuration can be welded for the first time a piston tube 3, of relatively thin wall, to a saucer of the stop 6 of relatively thick wall, which has no neck or stopper, without the stop plate being necessary to make No kind of preparations for welding cords.

Due to section 4 of the piston tube 3, which widens radially, conically, towards the top plate 6, it they can reduce the tensions that act on the cord or the welding cords, as will be explained in greater detail using figure 2.

After introducing the spring pack 13 and of mounting the sheath of the stop 1 with the piston of the stop 2, the ring elastic that forms the stop 14 is inserted into the slot 15 provided for this purpose, to limit the maximum piston output of the stopper 2, with which the top is ready for use.

Figure 2 shows a longitudinal section a through a stop, one of whose halves, the upper one, is carried out according to the state of the art and whose other half, the bottom, is made according to the invention, for which the Piston tube is provided in its extreme area, close to the top 6 saucer, of a section 4 that widens radially towards the top plate 6. The top made according to the state of the technique has a relatively thick wall plunger tube and a top 20 saucer with a forged neck 21. It was also complex preparations of the cords of welding in the area of the weld bead 22. While the radius r1, r2 is the same in both cases, the distance between line of attack of a force P acting off-center and outside the piston tube, on the stopper plate 6 and the cord outer welding, is shorter at the top made according to the invention (a1 <a2). In this way, the effective lever for calculating local bending stresses on the top plate, on the top designed according to the invention.

The increase in diameters D1 and d1 going to D2 and d2 impacts very advantageously, since tensions are reduced in the weld bead. The reduction is in proportion to the increase in diameter according to the third power, since the moment Resistant W is calculated as follows:

W = \ frac {(D4 - d4) * \ pi } {D * 32}

In addition, in case of off-center load, the flow of force in the saucer-tube zone is remarkably better thanks to having reduced the lever length. This finally allows the use of lower thickness piston plungers of wall as well as thinner butt plates.

Thanks to the radial widening of the tube The piston can also be welded on its inner face, without this reason has to reduce the guiding length f (f1> f2) between the cap sleeve and the plunger tube, which reduces the clamping forces between the stopper sleeve and the plunger tube in case of off-center load and therefore also the forces of friction between the two pieces. Thus, the stopper plunger it has an elastic path greater than equal force P and equal distance l (l1 = l2), which increases security against derailment when cornering.

A stopper piston of this class can be manufactured very easily, quickly and economically, since you can use a flat top plate, without any neck and without Preparation of the weld bead. It turns out especially attractive to use a piston tube 3 manufactured by deformation cold plastic, since in its manufacture they do not occur chip-shaped waste.

It should be noted that the embodiment example above shows only one possible embodiment of a bumper, but other bumper designs are perfectly possible that differ from the previous example, within the framework of the volume of protection defined in the claims.

Claims (9)

1. Stop for vehicles on track, with a stop sleeve (1) to fix the vehicle on track and a piston of the stop (2) axially movable, resting on the stop sleeve (1) through a damping device (13 ) with a piston tube (3) and a stopper plate (6) disposed at the end of the latter, where the piston tube (3) has a section (4) in its end zone near the stopper plate (6) which widens radially towards the top plate (6) characterized in that the top plate (6) is welded in the section (4) that widens radially. 2. Stop according to claim 1, characterized in that both a peripherally welded bead (9, 10) is disposed both by the inner face and the outer face of the radially widening section (4). 3. Stop according to one of the preceding claims, characterized in that the section (4) widens conically in the radial direction. 4. Stop according to one of the preceding claims, characterized in that the section (4) that widens radially towards the stop plate (6) is produced by cold plastic deformation. 5. Stop according to one of the preceding claims, characterized in that the piston tube (3) is widened by cold plastic deformation to a predetermined nominal diameter. A stop according to one of the preceding claims, characterized in that the piston tube (3) is provided on the inside of a groove (15) to accommodate an elastic ring (14), which forms a stop that limits the maximum outlet of the stopper plunger (2). 7. Method for the manufacture of a stop made according to claim 1, characterized in that the plunger tube (3) is widened by cold plastic deformation to a given inner diameter and is provided in its end zone, close to the stop plate (6), of a section (4) radially widened by cold plastic deformation. A method according to claim 7, characterized in that the stop plate (6) is welded to the section (4) that widens radially. 9. Method according to claim 8, characterized in that the stop plate (6) is welded to the section (4) that widens radially, both on the inner face and on the outer face.