SI21092A - Plunger buffer - Google Patents

Abstract

The invention relates to a plunger buffer for mobile support structures (2), in particular for rail vehicles, comprising a buffer housing (10), a baseplate (11) that is fastened to the support structure (2) in a fixed manner, a guide plunger (12) attached to the baseplate (11) and a displacement member (13) that can be displaced in relation to said guide plunger (12). The displacement member (13) is directed in its displacement by the guide plunger (12). The plunger buffer also comprises a force transmission member (20) for flexibly coupling the displacement member (13) to the support structure (2). The buffer housing (10) is configured in such a way that the guide plunger (12) or the displacement member (13) is deformed in a controlled manner above a threshold value for the displacement of said displacement member (13) or for the forces to be transmitted, without deforming or altering the bedding of the baseplate (11). The aim of the invention is to ensure that the plunger buffer (1) can absorb energy by deformation and nevertheless be configured with the same dimensions and fittings as known plunger buffers, thus enabling plunger buffers to be interchangeable in existing rail vehicles. To achieve this, the force transmission member (20) is configured in such a way that in addition to the controlled deformation of the guide plunger (12) or the displacement member (13), the function of the force transmission member (20) is overridden above the threshold value for the displacement of the displacement member (13) or for the forces to be transmitted.

Description

Telescopic bumper

The invention relates to a telescopic bumper according to the introductory part of claim 1.

This type of telescopic bumper is known from DE 462 539.

For telescopic bumpers for freight wagons or locomotives, such as those known from, for example, the book Elektrische Triebfahrzeuge by K. Sachs., Volume 1 - Allgemeine Grundlagen und mechanischer Teil - Zal. Springer-Verlag Wien, New York, 1973, p. 656 et seq., It is a matter of taking over not only gusts in the longitudinal direction of the vehicle but also transverse forces in the transverse direction of the vehicle. Known telescopic bumpers have a housing that has a base plate (bottom of the bumper) attached to the vehicle frame and a guide sleeve in one piece with it, which is a fixed component and a movable bar with a bumper plate on the front of the bumper. as a moving component. The handpiece slides along the outer or inner surface of the guide sleeve that guides it. Between the bumper plate and the bottom of the bumper, either a spring element or a spring damper element is arranged inside the bumper housing. The spring path of typical telescopic bumpers is 100 to 105 mm, exceptionally 150 mm. The length of the housing is typically 620 to 650 mm. Thus, only a small fraction of the total construction length is used for the spring path to shorten the bumper. When the bumper is loaded with a high impact, when it comes to exceeding its energy absorption capacity, the bumper may break with the subsequent overload and deformation of the thymic vehicle's load-bearing structure.

In order to avoid deformation of the load-bearing structure as much as possible in the case of heavy-duty bumper loads, it is known from published patent application EP 0 826 569 A2 that a power box is provided between the frame of the vehicle and each telescopic bumper. , which deforms when exceeding the permissible limit for shock loads. The disadvantage of this known damper device is that it is not suitable for retrofitting available freight wagons and locomotives, since the total length of the impact box and bumper exceeds the mounting length and size of the mounting plate of the available telescopic bumpers.

DE 462 539 already discloses a telescopic bumper for thymic vehicles with a bumper housing, consisting of a fixedly fixed floor panel on the load-bearing structure, on the base plate of the guiding sleeve and with respect to the guide sleeve of the movable moving part. The moving part is guided by the guide sleeve in the moving motion. The well-known telescopic bumper further comprises a spring-loaded spring-shaped part for the feed connection of the moving part with the supporting structure. The wall of the moving part is weakened in one place, so that the leaning of the moving part on the base plate results in a controlled deformation of the movement part without deforming or changing the position of the floor panel. In the deformation of the moving part, the load-bearing part is further compressed, which results in the fact that the spring force continues to grow and is added to the increase in the force causing the deformation of the moving part. In the aggregate, however, there is a sudden increase in force, whose peak force only decreases. Furthermore, the deformation path is very small compared to the spring path, so that the energy dissipated during deformation is relatively small. Lastly, in the known construction, in addition to the normal movement path of the moving part, the guide sleeve must be shortened by the deformation path, which further results in the reduction of the length of the overlap between the moving part and the guiding part.

It is an object of the invention to construct a telescopic bumper of the aforementioned type in such a way that, with a significantly larger energy uptake, the additional shortening of the bumper lies in the size of the spring path and the movement of the moving part occurs at a substantially constant level of force.

The present invention is solved by the features of the characteristic part of claim 1.

The preferred details and further performance features of the inventive telescopic bumper can be seen in the sub-claims.

The invention will now be further explained on the basis of the accompanying drawings of the embodiments presented. In doing so, they show:

FIG. 1 is a first exemplary embodiment of an inventive telescopic bumper in extended ground state, schematically in longitudinal section,

FIG. 2 is a telescopic bumper of FIG. 1 in the state of maximum displacement without deformation,

FIG. 3 is a telescopic bumper of FIG. 1-2 in the state of maximum displacement at deformation,

FIG. 4 is a force / path diagram for FIGS. 1-3 presents states of an inventive telescopic bumper, and

FIG. 5 to 7 three variants of the inventive telescopic bumper are schematically in longitudinal section each.

A first embodiment of the telescopic bumper 1 of the invention shown in FIGS. 1 to 3, consists of a housing 10 of the bumper having a fixed part and a movable part. Sketch of FIG. 1 shows a telescopic bumper 1 in the extended basic position, which in FIG. 4 corresponds to position A.

The non-moving part of the bumper housing 10 comprises a base plate 11 (the bottom of the bumper) which is attached, for example, screwed, to the load-bearing structure 2, in particular to the frame of the non-shown thymic vehicle. The base plate 11 carries a tubular guide sleeve 12 and is preferably connected in one piece to one of the front faces of the guide sleeve 12, for example. The movable part of the housing 10 of the bumper consists of a movable part 13 in the form of a rod, which is movable inside the guide sleeve 12 by sliding along the inner wall thereof. The inner wall of the guide sleeve 12 in this case receives the guiding forces for sliding movement of the moving part 13 in the radial direction. The front side of the moving part 13 projecting out of the guide sleeve 12 is closed by the bumper plate 14, which, in the shunting of the thymic vehicle, receives shock forces.

The movable part 13 and the guide sleeve 12 require a certain minimum length of cover for the purpose of limiting friction and self-restraint protection due to pinching, to provide guidance also for lateral operating loads caused by friction on the bumper plate 14, or for exceptional or oblique operating loads. (e.g., when driving team vehicles in a corner / S-turn). At the same time, both parts 12, 13 need to be provided with the necessary clearance as a prerequisite for freedom of movement. The requirement for as long as possible the overlap of the guide sleeve 12 and the moving part 13 contradicts the requirement that the parts 12, 13 be able to move clearly beyond the normal spring path (stroke) in a given deformation without increasing the overall structural length of the bumper. This means that the inventive telescopic bumper 1 looks from the outside and has dimensions like a known telescopic bumper.

In order for the opposing requirements to be fulfilled, both parts of the bumper housing, when the normal spring path is exceeded, are used to deform energy beyond its normal guiding function through deformation. Suitably, either the guide sleeve 12 or the moving part 13 or both components 12, 13 are both simultaneously or temporally offset. The deformation is of such a nature that the lengths of these components 12, 13, which in normal operation contribute to the overlay and thus to the control, are shortened.

A further condition for widespread displacement at a limited force level is that the load-bearing member 20, which is disposed between the movement member 13 and the guide sleeve 12 and which in normal operation serves to transmit longitudinal force, permits additional shortening without establishing any unacceptably high force level. .

In the case of known bumpers for thymic vehicles, commonly used force transfer components, such as ring springs, elastomy springs, rubber springs with or without parallel hydraulic damping elements, in the aspirated size class, do not allow any shortening due to block construction. .

In the invention bumper 1, in contrast, inside the housing 10, as a silo-bearing part 20, two suspension elements 21, 22 of different diameters are arranged one by one and connected to each other by bridging part 23. The bridging portion 23 is so constructed that, when the limit load is exceeded, for example, at the site intended for the intended fracture, the shear breaks, allowing the suspension elements 21, 22 to slide telescopically into each other without transmitting longitudinal forces.

In the embodiment shown (FIGS. 1 to 3), the bridging portion 23 has the shape of a flat profile disc. Instead of a straight profile, a profile similar to a pot or hat may also be used for the disc of bridging part 23 in a non-shown manner. The left end of the first spring element 21 rests on the inner surface of the bumper plate 14, while the right end of the second spring element 22 rests on the inner surface of the floor plate 11. The bridging portion 23 has a point 24 of the desired fracture in the shape of one another near its outer edge. recessed annular grooves. The position of these annular grooves is so selected that the first spring element 21 is radially supported beyond the annular grooves and the second spring element 22 by the lateral annular grooves on the bridging portion 23. Bridging section 23 is, as shown in FIG. 3, when the maximum load is exceeded or when the maximum travel path is reached, it breaks inside the housing 10 of the bumper at the point 24 of the desired fracture. The fracture of the bridging portion 23 means that there is no more bridging between the suspension elements 21, 22 and thus the joint effect. The smaller diameter spring element 22 then moves to the larger diameter spring element 21.

Sketch of FIG. 2 shows the telescopic bumper 1 in its most compressed state (in FIG. 4, position B). From this position of the movable part 13 further, only the deformation of the guide sleeve 12 can occur, as illustrated in FIG. 3. The groove 14a provided at the passage 14 of the bumper at the passage to the guide sleeve facilitates the entry of the guide sleeve 12 into the condition when the bumper fails, ie. when the sleeve is first extended to the breaking point, then continuous cracks appear in the longitudinal direction and the resulting individual segments 12a of the sleeve 12 swing out. Such destruction of the bumper has several advantages. On the one hand, deformation begins progressively and without a peak of force. The guide sleeve 12, which has a relatively large wall thickness due to its dimensioning to the operating loads, can then deform below a not too large, uniform force level (the drawn line between positions B and C in FIG. 4). In addition, the guide sleeve 12 can be destroyed practically completely without any length remaining. Other outward protruding segments 12a do not require any structural length and these segments also do not impede progressive deformation surgery. A further advantage is that the lateral guidance against oblique or extraordinary forces is maintained throughout the deformation path unchanged or even increased.

Different states of the inventive telescopic bumper 1 according to FIGS. 1 to 3 are explained with the help of FIG. 4 Force / pot characteristics shown. Further to the normal operating range between positions A and B (spring path 100 to 105 mm) in the deformation zone (between positions B and C) there is a further shortening of the moving part 13 by about 200 mm at a uniformly high force level. The full functionality of the telescopic bumper prescribed by the standards is maintained. The diagram of FIG. 4, in the area of normal operation, the movement of the moving part 13 follows in accordance with the characteristic of serially coupled spring elements 21, 22 along a drawn, broken curve. The knee in the curve occurs when a more gentle branch of the curve follows the softer spring characteristics of the series attachment of the two spring elements 21, 22 and when, upon further movement of the moving part 13, the softer than the two spring elements 21, 22, it becomes harder than both spring elements with their steeper characteristic in the force / path diagram. The dashed curve in the normal operating range indicates the additional damping effect of the hydraulic damper provided if necessary. At the end of the 100 mm displacement (position B), the bridging portion 23 between the spring elements 21, 22 bursts when the spring effect of the spring elements 21, 22 strikes. ends what we see with a slight steep descent of the curve at 100 mm of travel path. Since fracture of bridging section 23 deforms the guide sleeve 12 by splitting into segments 12a, the steep decline of the curve at 100 mm immediately stops again and the slope of the force / path along the path of displacement 200 mm begins (position C) when the force level is virtually unchanged. This unchanged force level corresponds to the condition of controlled deformation by splitting of the guide sleeve 12. The end of the travel path at 200 mm corresponds to FIG. 3, when the moving part 13 hits the base plate 11. The diagram of FIG. 4 then goes in the direction of position D steeply up.

In order to ensure the shortening of the load-bearing part 20, in embodiments according to FIG. 1 to 7 the following measures are envisaged. Two spring elements 21, 22 (eg ring springs) of different diameters are used. The flat bridging portion 23 with the desired fracture site 24 forms a silo-joint in normal operation. It is possible to use the power of two suspension elements 21, 22 of different lengths and / or different rigidity and / or of different materials (steel / elastomer / rubber) so that a progressive spring characteristic can be obtained in normal operation. This may have driving dynamics advantages for coupled thymic vehicles (drawn line between positions A and B in FIG. 4).

A further possibility of achieving favorable operating characteristics is the parallel connection of the dashed out hydraulic damper 40 e.g. inside the smaller diameter spring element 22. Thus, a higher energy uptake can be achieved in normal operation (dashed line between positions A and B in FIG. 4). Unlike the known bumpers with hydraulic dampers, the attachment of a larger diameter spring 21 is limited by the increase in the force at high gusts by the stiffness of this spring element. This is especially reflected in the impact of bumpers of different designs (with or without hydraulic damper) on the course of the force / path.

In the FIG. 1, we see that the bridging part 23 rests on the backrest 30 or on the damper housing 40. The moving part 13 further rests on two or more along the outer circumference of the bridging part 23 of the radially projecting studs 23a. The function of the backrest 30 and the studs 23a is to assist the bridging portion 23 in isolation. By way of example, the selected contact sites located e.g. steaming diametrically, so that, at a certain position of the displacement of the moving part 13 in the bridging portion 23, a sudden concentration of tension is obtained, which leads to the direct isolation (failure and shear interruption) of the bridging part 23. The isolation is thus controlled by the path. A sensible choice of design tolerances ensures that this occurs just before the moving part 13 is hit on the guide sleeve 12. This is shown in FIG. 4 sees at a brief forcing of the force level. The design of this type is advantageous because it avoids the summation of overlapping of the transmission of the force through the bridging part 23 (typical for normal operation) and the transfer of force through the case-forming housing of the adjacent housing parts (typical of the deformation zone), thereby creating unwanted high force peak. This safety function of bridging part 23 facilitates the design of the hydraulic damper 30. This can be optimized preferably against lower and medium load speeds and thus easier to manufacture.

One or both geometric isolation aids may be waived. In this case, the force-controlled bridging section 23 fails when its load limit is reached. Independent of the existence of isolation aids, e.g. hydraulic damper 30, even before reaching the common spring path of the spring members 21, 22. Even if the result of this operation is a transient intrusion in the force / path characteristic, it is perfectly desirable to prevent the formation of unacceptably high force peaks.

Sketch of FIG. 3 shows a telescopic bumper 1 in the final position at the end of the deformation zone (position C in FIG. 4). Large portions of the guide sleeve 12 have deformed and projected as individual segments 12a. We see a bridged part 23 and a telescopically slung spring element 21, 22 being disposed of each other. The telescopic bumper 1 has reached its extreme possible shortening. Further deformation will only be possible with extreme force input with complete destruction and a steeply rising force (Fig. 4, position D).

The rise of force can be delayed by making the movement part so that it can be compressed, for example by locally weakening the section. Thus, in the last phase of the deformation zone, deformation of the hitherto deformed movement part 13 is further deformed, thereby

-9continues a further movement reserve at a higher force level (FIG. 4, dotted line C-D ').

FIG. 5 shows the version in FIG. 1 of the telescopic bumper shown when the arrangement of the suspension elements 21, 22 is replaced and there is no assistance to isolate via the studs 23a on the bridging portion 23. The backrest 30 as a device for isolation is located here on the moving part 13. The function of this version does not change due to the replacement of the arrangement of the spring elements 21, 22.

In the FIG. 6 is a telescopic bumper in which the moving part 13 guides the guide sleeve 12 from the outside. The passage between the guide sleeve 12 and the base plate 11 may be rounded to facilitate the failure path of the moving part 13. When the extreme movement of the normal operating range (FIG. 4) is exceeded, the moving part 13 rests on this rounding and begins to deform. Tearing and protruding segments occur near floor panel 11. This arrangement may have geometric advantages for special mounting conditions. Guide sleeve 12 may have additional shrinkage capacity.

FIG. 7 shows a telescopic bumper 1 in which, in comparison with embodiment FIG. 6 spring elements 21, 22 replaced. This does not change the function.

Alternatively, a fiber reinforced plastic or assembly made of various materials may be installed in place of the moving part 13 instead of the metallic material, thus making irregularities occur in geometry and more uniform failure modes in the case of forces.

Compared to known telescopic bumpers, the inventive telescopic bumper virtually triples the displacement path from 100 to 300 mm without damaging the supporting structure 2 (vehicle frame) of the thymic vehicle. In addition to the elastic, reversible energy absorption of a known telescopic bumper, which, depending on the suspension damping element, lies in the range of 30 to 70 kJ, deformation can absorb about 200 kJ of motion energy. A deformed telescopic bumper only needs to be replaced with a new telescopic bumper in case of deformation. Because inventive telescopic bumpers have the same dimensions and mountings as known, in everyday use

-1010 telescopic bumpers located, that existing thymic vehicles can be fitted with inventive telescopic bumpers without further ado.

Claims (11)

Patent claims 1. Telescopic bumper (1) for movable load-bearing structures (2) mainly thymic vehicles, with a body (10) of a bumper consisting of a locally fixed, on a load-bearing structure (2) of a fastening floor plate (11) mounted on a floor plate (11) the guide sleeve (12) and with respect to the guide sleeve (12) of the movable moving part (13), which is guided by the guide sleeve (12) during its movement, and with the silo-carrying part (20) for the coupling of the moving part (13) with the carrier structure (2), wherein the housing (10) of the bumper is designed such that, above the limit, for displacement of the moving part (13) or for the forces to be transmitted, to a controlled deformation of the guide sleeve (12) or the moving part (13) ) occurs without deformation or change of position of the floor panel (11), which means 1 one after the load-bearing part (20) is designed so that it is above the limit for the movement of the moving part (13) or for the forces to be transmitted , in addition to the controlled deformation of the guide sleeve (12 ) or the moving part (13) the function of the silo-carrying part (20) ceases to exist. Telescopic bumper according to claim 1, characterized in that in controlled deformation the wall of the guide sleeve (12) and / or the moving part (13) extends beyond the breaking boundary at one axial end and is torn to segments (12a). Telescopic bumper according to claim 1, characterized in that, in controlled deformation, the walls of the guide sleeve (12) and / or the moving part (13) are axially compressed. Telescopic bumper according to one of Claims 1 to 3, characterized in that the silo-bearing part (20) has two spring-connected elements (21, 22) connected to one another by means of a bridging part (23), and is bridged part (23) so designed that, above the limit for the displacement of the moving part (13) or for the force to be transmitted, the connection between the suspension elements (21, 22) is broken. Telescopic bumper according to claim 4, characterized in that a disc with at least one desired break point (24) is provided as a bridging portion (23). -1212 Telescopic bumper according to claim 5, characterized in that the disc has a straight or pot-like profile. Telescopic bumper according to one of Claims 4 to 6, characterized in that the bridging part (23) is arranged in the moving path of the moving part (13) and, when hit by the moving part (13), on the bridging part (23) and is thus excluded. Telescopic bumper according to one of Claims 4 to 7, characterized in that a support (30) is provided for the bridging part (23) such that when the bridging part (23) is hit on the abutment (30), it first switches off. Telescopic bumper according to claim 7 or 8, characterized in that the contact points of the bridging part (23) to hit the moving part (13) and / or the end support (30) are so designed that, when hit, local stress concentrations occur . Telescopic bumper according to any one of claims 4 to 9, characterized in that a hydraulic damper (40) is arranged parallel to the spring element (21, 22) of the silo-bearing part (20). Telescopic bumper according to one of Claims 1 to 10, characterized in that the part between the guide sleeve (12) and the moving part (13) which is not involved in the deformation is designed to be hit on the obstacle at the end of the movable paths within it.