SK51012006A3 - Tube bumper - Google Patents

Abstract

The invention relates to a plunger buffer that comprises first and second guide elements in the form of a buffer housing (10) and a plunger (20). The aim of the invention is to allow a significant length reduction for the controlled deformation of the buffer housing in the event of overload and at the same time a sufficiently large overlap in the normal operation (compression until full plunger displacement is attained). For this purpose, at least one (20) of the two guide elements (10, 20; 10, 50) consists of two or more elongate sections (22, 24; 52, 54) disposed one after the other. The elongate sections (22, 24; 52, 54), in the area of their adjacent faces, are interlinked by one ore more predetermined breaking point(s) (23; 53) each and have different cross-sectional dimensions. When a defined impact force (triggering force) onto the buffer housing (1) is exceeded, the predetermined breaking point(s) (23; 53) tear(s) off and the elongate sections (22, 24; 52, 54) are telescoped into each other.

Description

Tubular bumper

Technical field

BACKGROUND OF THE INVENTION The present invention relates to a tubular bumper for movable or rigid support structures, in particular rail vehicles, with first and second tubular sleeve and ram guide members, wherein the tubular sleeve is rigidly attachable to the support structure and the ram is movable relative to the tubular sleeve. is guided by its sliding movement through the tubular sleeve, and with the force transmission member to a flexible connection of the ram to the supporting structure. Such a tube bumper is well known.

BACKGROUND OF THE INVENTION

The known tubular buffers are used as such in locomotives, freight wagons or passenger wagons. side bumpers to catch and absorb impacts in the longitudinal direction of the vehicle. In the event of oblique or eccentric impacts, additional transverse forces in the transverse direction of the vehicle and / or in the vertical direction may also be applied to the bumpers. Structurally, the known tubular buffers consist of a bumper housing and an internal force transmission member, generally an element with spring and / or damping properties, which is located therein. The sleeve takes the guide in the longitudinal direction and retains the transverse forces while the internal resilient and / or damping members are located to transfer the forces in the longitudinal direction. There are structures in which a portion of the housing is fixedly coupled to the vehicle, i. the sleeve, located from the outside, and the guided sliding part (ram) located inside. However, there are also constructions with the opposite arrangement in which the housing is located inside and the ram encircles the housing from the outside. In each case, the sliding surfaces are cylindrical and are generally continuous over the entire range of abutment. The distance between the front and rear delimitation of the abutment area is referred to as the overlap length Lg.

In principle, in all tubular bumper designs, the overlapping length between the fixed (sleeve) and moving part (ram) is as large as possible to accommodate lateral forces. The friction force and wear between the guide parts, i.e. and the ram, and the risk of jamming or wedging of the guide parts is reduced. The length of the overlap should be clearly greater than the diameter of the cylindrical guide surfaces in order to avoid jamming and self-locking of the ram housing. It usually represents many times the bumper travel. The maximum possible overlap length may at most be the value that results from the overall design length of the bumper minus the thickness of the bumper plate, the thickness of the bottom of the casing and twice the stroke of the bumper. At this maximum overlap length, both ram and bushing are free to run.

Typically, known tubular buffers have a design length of approximately 620 to 650 mm and a bumper stroke - this corresponds to the spring travel of the spring element in the range of 100 to 110 mm, as this is standardized for certain vehicle categories in the European Directive (for example UIC-Merkblätter 526, 528) . The outer diameters of the ram and cylindrical housing lie between the attachment flange and the bumper plate typically in the range of 200 to 250 mm. The overlap length is generally in the range of 250 to 350 mm.

Upon reaching the maximum bumper lift, the guide parts (sleeve and ram) of known tubular bumpers hit the defined stops. In the event of a start-up impact that exceeds the energy-absorbing capability of the tubular bumpers, the tubular bumper will come to rest and transmit very high peak forces to the rigid vehicle structure. There is then considerable damage to the construction of the vehicle.

In order to prevent or mitigate such damages, it is known to provide the tubular bumper guide parts such that, once they have reached the defined stops, there is an additional possibility of shortening them under controlled deformation and energy absorption. For example, in German Pat. 462,539 describes the permissible deformation location in the bumper ram. With this construction

However, only relatively short additional deformation paths can be achieved. In addition, due to the point of permissible deformation in the bumper ram, the overlap length must be reduced accordingly. In another tubular bumper with a destructible member known from German patent specification no. 747 330, part of the bottom of the bumper is cut off when overloaded, and then the front part of the outside of the sleeve is pushed to a smaller diameter in the rear part under deformation and high force. With this design, the overlap length can remain unchanged compared to a conventional bumper. However, an opening and additional structural space must be left to immerse the entire bumper housing into the vehicle structure. The essential components of the bumper shall be displaced as a whole, the overall design length of the bumper shall not be reduced. Finally, in another tubular bumper as described in German document no. No. 100 37 050, structural elements with shortening capability and energy-absorbing capacity are provided. This design permits relatively long travel paths beyond the normal bumper travel, but unlike German document no. 747 330, without the need for additional structural space within the vehicle structure. The disadvantage, however, is that the length of the overlap must be reduced by as much as the travel distance above the normal bumper stroke is extended. If long feed paths are to be realized, the overlap length must be reduced to a very small value. The length of the overhang can reach very small values, which is considerably smaller than the diameters of the sleeve and ram, which results in a high risk of wedging and jamming. In practical application of this principle, a compromise must be chosen between the feed length and the overlap length.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a tubular bumper of the type described above with a large shortening length for controlled deformation under overload, as well as a sufficiently long overhang during normal operation - springing up to full bumper stroke.

4. Summary of the Invention

This object is solved by a tubular bumper for movable or fixed support structures, in particular rail vehicles, with first and second tubular sleeve and ram guide members, wherein the tubular sleeve is rigidly mountable on the support structure and the ram is movable relative to the tubular sleeve in the longitudinal direction. and is guided in its displaceable movement through the tubular sleeve and with the force transmission member to a flexible connection of the ram to the supporting structure according to the invention, characterized in that at least one part of the two guide parts consists of two or more elongated ones sections, which in the region of their mutually adjoining faces are connected to each other by one or more breaking joints and have different cross-sectional dimensions such that when a certain impact force (activation force) on the tubular bumper is exceeded, the breaking joint breaks and elongated sections scopically slip into each other.

Preferably, the guide part located in the interior consists of mutually arranged elongate sections.

The guide element which is located externally also advantageously consists of mutually arranged elongate sections.

Advantageously, one of the guide pieces is designed such that after the activation force is exceeded, the controllable deformation is shortened at a high, substantially constant force level.

The guiding parts are dimensioned such that, during the slide movement of the ram, the breaking of the breaking joint first takes place, and only shortly thereafter the deformation of the other guiding part begins.

The telescopic sliding elongate sections preferably have a cylindrical tubular shape.

Preferably, the frangible connection forms a one-piece component together with one or more telescopically displaceable elongate sections.

The breaking joint is preferably arranged radially between the adjoining faces of the telescopically displaceable elongated sections and is designed as continuous or discontinuous in the circumferential direction of the section.

Preferably, a spring and / or damping element is used as a force transfer member which is supported between the support structure and the end plate of the elongated section with smaller cross-sectional dimensions, the spring and / or damping element being designed to be shortened to a maximum stroke of the bumper ram during normal operation.

Finally, the lengths of the telescopically displaceable elongate sections are preferably equally large.

BRIEF DESCRIPTION OF THE DRAWINGS

Examples of embodiments of a tubular bumper according to the invention are shown in the drawings which show

FIG. 1 shows a schematic longitudinal section of a first embodiment of a tubular bumper according to the invention in a spring-loaded ground state, in which two different embodiments are shown in the individual halves of the figures;

FIG. 2 is a schematic longitudinal section through the embodiment of FIG. 1 in a state of maximum displacement exceeding the normal lift of the tubular bumper;

FIG. 3 is a schematic longitudinal section through another embodiment of a tubular bumper according to the invention; and

FIG. 4 shows a schematic longitudinal section through the embodiment of FIG. 3 in a state of maximum displacement exceeding the normal lift of the tubular bumper.

DETAILED DESCRIPTION OF THE INVENTION

The embodiments of the tubular bumper 1 according to the invention shown in FIG. 1 to 4, each comprising two coaxially arranged guide pieces, wherein the first guide piece is formed by a rigid tubular sleeve 10 (FIGS. 1 and 2) or 50 (FIGS. 3 and 4) and the second guide piece is formed by an axially movable slide 20. It is expedient and corresponds to the state of the art if both guide parts have a cylindrical tubular shape, particularly in the area of their sliding surfaces. The description of the exemplary embodiment is limited to this construction in the following.

In the following, the construction and operation of the first embodiment of FIG. 1 and 2.

The tubular sleeve 10 is closed at its right axial end by a mounting flange 11 or a bumper bottom which is attached, for example bolted, to the support structure 2 of a rail vehicle (not shown). The fastening flange 11 carries the tubular sleeve 10 and is preferably integrally connected, for example welded, to one end of the tubular sleeve 10. The movable ram 20 comprises a buffer plate 21 and a tubular section 22 which is slidably slidable on the inner wall of the tubular sleeve. 10. The inner wall of the tubular sleeve 10 retains guiding nets for the slide guide 20 in the radial direction. The protruding face of the ram 20 projecting from the tubular sleeve 10 is closed by a bumper plate 21 which is subjected to impact forces, in particular when the rail vehicle is being moved. So far, the construction corresponds

The pipe bumper 1 according to the invention of the construction of known pipe bumpers, i. this tubular bumper 1 has the shape and dimensions of a known tubular bumper when viewed from the outside.

In contrast to the prior art, an extension sleeve 24 whose diameter is smaller than the diameter of the tube section 22 is coaxially mounted on the free axial end of the ram section 22, the diameter of which is smaller than the diameter of the pipe section 22. Attachment of the extension sleeve 24 is accomplished by breaking. the sleeve 24 with the inner surface of the tubular section 22 in the region of its free axial end. The breaking joint 23 may be in the form of a shear pin or an intermittent weld bead.

The extension sleeve 24 is closed by a faceplate 24c on its front end 22 connected to the tubular section 22 and is provided with a collar 24d on its opposite end to support the inner surface of the sleeve 10.

In the first alternative, which is shown in the upper half of FIG. 1, a force transfer member 30 is provided within the extension sleeve 24 as a resilient and / or damping element 30a that is supported between the end plate 24c of the extension sleeve 24 and the attachment flange 11 of the tubular sleeve 10. The force transmission member 30 is formed. such that it can be shortened only after reaching the maximum stroke of the ram 20 in its normal operation when the collar 24d of the extension sleeve 24 hits the attachment flange 11 of the tubular sleeve 10 and the breaker joint 23 remains intact.

In a second alternative embodiment, shown in the lower half of FIG. 1, the faceplate 24c is missing. Inside, on both sides of the open extension sleeve 24 and the tubular section 22 of the ram 20, there is a force transfer member 40 designed as a spring and / or damping element 40a that abuts between the buffer plate 21 and the attachment flange 11 of the tube sleeve 10. the force transmission is designed so that it can be shortened over the maximum stroke of the ram 20 when in case of controlled deformation of the tubular sleeve (Fig. 2)

The extension sleeve ring 24d of the extension sleeve 24 hits the attachment flange 11 of the sleeve 10 and the breaker joint 23 breaks or tears off as the slide section 22 of the ram 20 is moved further. This case is shown in FIG. Second

As shown in FIG. 2, the breaking joint 23 breaks when the maximum load is exceeded or the maximum ram travel 20 is reached. The breaking of the breaking joint 23 means that the extension sleeve 24 can be telescopically moved inside the tube section 22 of the ram 20. Further sliding movement of the buffer plate 21 and the tube section 22 of the ram 20 is damped by deformation of the tubular sleeve 10 and, in the alternative according to the lower half of FIG. 1 additional to the power transmission member 40. Indeed, once the bumper plate 21 encounters the free front edge of the tubular sleeve 10, it will begin to move the bumper plate 21 away from the free front edge of the tubular sleeve 10 starting from deformation of the tubular sleeve 10 by ramming or alternatively expanding it, depending on the mechanical design of the tubular sleeve. the sleeve of the tubular sleeve 10 is in the lower half of FIG. 2, indicated by the ripple 40b. The case of expansion of the tubular sleeve 10 is in the upper half of FIG. 2 indicated by the individual segments 40a. In both cases, the axial length of the tubular sleeve 10 is shortened so that the tubular section 22 of the ram 20 can be displaced practically to the inner surface of the fastening flange 11 with its right end end 11. In this end condition the extension sleeve 24 is fully inserted into the tubular section 22 the end of the tubular section 22 abuts on the collar 24d of the extension sleeve 24. This end condition is shown in FIG. Second

In the drawings, the following designations are used for the length dimensions, which are used in the following description:

h overall length of tubular bumper,

Lq the length of the overlap between the tubular sleeve 10 and the ram 20, _{12 the} length of the tubular section 22 of the ram 20,

- the length of the extension sleeve 24 of the ram 20 corresponds to the length of the second section length L0 of the overlap, _{14 the} length of the free travel of the ram 20 for the normal bumper lift, 15 the length of free travel of the tubular sleeve 10 for the normal bumper lift.

L is the length of the first overlap length corresponding to the length of the front section of the sliding surface;

17 the length of the third overlap length corresponds to the length of the rear sliding surface,

L / total length of tubular bumper 1 at maximum displacement beyond normal bumper travel.

If, of the known tubular bumper design, which have a long overhang length, but where the ram 20 and the tubular sleeve 10 abut against each other at the same time and along the entire overhang length, the invention offers the possibility to shorten both guide parts 10, 20 and maintain deformation forces through it all at a controllable level. The theoretical possibility of deforming the two tubular guide pieces 10, 20 together would, due to their large common wall thickness and mutual interference during the deformation, lead to an unnecessarily very high level of forces.

The shortening and warping functions were therefore separated and assigned to the guide pieces 10, 20 individually. One of the two guide pieces 10 or 20 is to perform shortening or non-resistance shortening which requires little space, while the remaining guide pieces 20 or 10 are to be shortened in deformation to achieve the desired level during feed. forces.

It is not critical for the purposes of the invention which of the two functions is assigned to one or the other of the two guide parts 10, 20. However, it seems less effective,

The deformation function is assigned to the inner of the two guiding parts 10, 20 because inside the tubular bumper 1 the structural space is largely filled with spring and / or damping elements and therefore very little structural space is available for the deformation processes. For the sake of simplicity, this case is therefore not considered in the following description.

For these reasons, it is advantageous to let the outer of the two guide pieces 10, 20 deform outwardly, since there is sufficient construction space there. In this case, the inner guide part of the two guide parts 10, 20 must carry out a shortening which, on the one hand, does not prevent the outer guide part from deforming and, on the other hand, produces as little resistance as possible so that the total deformation force does not increase excessively. Importantly, the length of the inside guide portion in the ground state will not decrease, as this could be at the expense of the length of the overlap. For this purpose, the slide between the ram 20 and the tubular sleeve 10 is divided into three sections (length dimensions Le, L3 and L7), of which the first section L ₆ and the third section L ₇ are functionally required as sliding surfaces in order to ensure normal operation. with the required overlap length, they performed the guiding function. To surface pressures in the transverse or during normal operation is too large, not least of sections l_ ₆ and L ₇ fall below certain limits. L_3 central section has a reduced diameter and have not serve as a sliding surface, but must also form a rigid connection between the first section and the third section L_6 L ₇ to be satisfied as a whole a guide function. Due to the fact that the diameter of this middle section L ₃ is reduced as much as necessary to be inserted into the inside diameter of the tubular first section L ₆ , a relatively large, but with little resistance, shortening within the guide guide is achieved. part. The second and third section ₃ l_ l_ and ₇ may be similar to a telescope inserted inside the first section l_ _6, and the downstream section of L _second For the whole function it is also necessary that the two mutually sliding portions were for normal operation and firmly attached so they can be reliably transmitted bending moments between the first section and the third section L6 l_ _7th It is also necessary that the connection between the first section ₆ l_ (tubular portion 22) and the second section S ₇ (extension housing 24) is formed

11, which breaks the rigid connection so far in the event of an overload condition. This can be done, for example, by a shear pin or other breaking joints, or alternatively by locally weakened connecting bridges. The frangible connection 23 may be distributed continuously on the periphery of the extension sleeve 24 or may consist of uniformly or unequally distributed discrete elements. Uneven distribution may be desirable, for example, in order to increase lateral stress stability in a certain direction without altering the breaking force in the longitudinal direction.

At the same time, the described measures can meet the contradictory requirements for long overhang during normal operation, long shortening during controlled deformation after overloading, and eliminating the need for additional structural space in the vehicle structure.

Very large shortening can be achieved, up to approximately half of the original design length. This is shown in FIG. 2, indicated by the length dimension Lf.

The principle of the mutually engaging sections 22, 24 inside the guiding element can be combined with various deformation patterns of the outside guiding element, both with the expansion and tearing of the pipe and, for example, with regular or irregular ramming or pipe folding, such as FIG. 1 indicated by 40a and 40b.

The described principle is applicable to both the tubular bumper structure with the inboard ram 20 and the tubular bumper structure with the inboard tubular sleeve 10. Such a structure can easily be imagined as a mutual substitution of the bumper plate 21 for the mounting flange 11.

The principle of telescopic guide sections of the guide parts can be extended in the embodiment according to FIG. 1 and 2 used additionally also on the tubular sleeve 10. This extension of the principle is explained on the basis of FIG. 3 and 4, at

12 in which the tubular sleeve is unlike FIG. 1 and 2 instead of the reference numeral 10 denoted by the reference numeral 50. The embodiment of the ram 20 is in the variant of FIG. 3 and 4 identical to the embodiment of the first variant of FIG. 1 and 2. However, unlike FIG. 1 and 2 in two parts and is embodied as telescopic sliding sections 52, 54 with an intermediate breaking joint 53. As shown in FIG. 4, the shortening ram 20 and the tubular sleeve 50 are telescopic. This shortening may take place with some desired resistance, for example due to FIG. 3 of the breaker joint elements 23, 53 or other resistive elements shown between the telescopically displaceable components. Optionally, an additional deformation element 60 may be provided between the extension sleeve 24 or its faceplate 24c and the ram 20. This additional deformation element 60 may be configured so as to achieve the desired level of forces when the components 22, 24 and 52, 54 move relative to each other. Alternatively, the additional deformation element 60 in the form of two separate deformation bodies 60a and 60b may be arranged between the buffer plate 21 and the tubular housing section 52 (the deformation element 60a) and between the ram section 22 and the collar 24d of the extension sleeve 24.

In FIG. 4 is the tubular bumper of FIG. 3 is shown in the state of maximum displacement. Obviously, the telescopic movement of the ram 20 and the tubular sleeve 50, or the deformation of the additional deformation element 60 or the deformation bodies 60a, 60b, took place simultaneously. Although such an embodiment of the tubular bumper according to the invention is relatively expensive, such an embodiment can still be expedient if the surrounding construction space is very limited. However, a simpler embodiment of FIG. 1 and 2, in which only the tubular section 22 of the ram 20, which is surrounded by the tubular sleeve 10, is designed as a telescopic slide.

The described principle of telescopic movement can meaningfully also apply to more than two mutually displaceable sections. Such an embodiment may be expedient if an even greater overall shortening of the pipe bumper is to be achieved and the necessary pipe bending is available in the circumferential direction of the pipe bumper.

-13priestor. It is understood that there is always a breaking joint between two of the several sections.

Due to the telescopic structure shown, the displacement function can be performed with or without resistance. As a result, the increase in the required force level during the displacement can only take place on the basis of a controlled deformation and an undisturbed outside guiding member. Due to the clear separation of function and their slight interactions, the design and controllability of the entire system is considerably simpler than in structures in which both guides 10, 20 are subjected to both deformation and interaction processes.

The construction can be further simplified by first tearing off takes place / break break-off joint 23 between the first section and the second section L_6 L ₃ in abutment contained within the guide part, and then a short time later there will be the start of deformation and the abutment of the outer guide part. Thus, during the controlled deformation, the activation force threshold and the mean force level can be separately dimensioned and modified from one another.

The described characteristics of the tubular sleeve can be combined with various designs of bumper springs. For example, the extension housing 24 is contained within the guide part, which comprises a second section L _3, and L of the third section _7, it may be provided with support in the form of a front panel 24c of the spring and / or damping element 30a. As a result, together with the activation / tearing off of the breaking joint 23, the spring action of the spring and / or damping element 30a can also be disengaged in order to prevent an increase in the force of the elongated travel path. In this case, it must be taken into account that the breaking joint 23 must additionally transmit the forces of the spring and / or damping element 30a applied during normal operation and must be sufficiently dimensioned for this.

Alternatively, the disabling of the spring effect can be waived if the spring and / or damping element 40a, which is suitable for large shortening, is used. In this case, the end plate 24c of the extension sleeve 24 is missing.

Claims (9)

Tubular bumper for movable or rigid support structures (2), in particular rail vehicles, with first and second guiding members in the form of a tubular sleeve (10) and a ram (20), the tubular sleeve (10) being fixedly fixed to the support structure ( 2) and the ram (20) is movable relative to the tubular sleeve (10) in the longitudinal direction of the vehicle and is guided by its sliding movement through the tubular sleeve (10), and with the force transmission member (30; 40) a supporting structure (2), characterized in that at least one part (20) of the two guide parts (10, 20; 10, 50) consists of two or more elongated sections (22, 24; 52, 54) arranged one behind the other. which, in the region of their mutually adjoining faces, are each connected to one another by one or more breaking joints (23; 53) and have different cross-sectional dimensions such that when a certain impact force (activation force) on the tubular bumper (1) is exceeded whether the joint (23; 53) breaks and the longitudinal portions (22, 24; 52, 54) are telescopically inserted into each other. Tubular bumper according to claim 1, characterized in that the inner guide part (20) consists of mutually arranged elongate sections (22, 24). Tubular bumper according to claim 1, characterized in that the outer guide portion (50) consists of mutually arranged elongate sections (52, 54). Tubular bumper according to one of Claims 1 to 3, characterized in that one of the guide parts (20, 10; 50, 10) is designed such that, after the activation force has been exceeded, it is shortened by a controlled deformation at a high, substantially constant level. forces. -165. Tubular bumper according to one of Claims 1 to 4, characterized in that the guide parts (10, 20; 10, 50) are dimensioned such that, during the slide movement of the ram (20), the breakage joint (23; 53) is first torn off and only shortly thereafter the deformation of the remaining guide piece (10) begins. Tubular bumper according to one of Claims 1 to 5, characterized in that the telescopic sliding elongate sections (22, 24; 52, 54) have a cylindrical tubular shape. Tubular bumper according to one of Claims 1 to 6, characterized in that the breaking joint (23; 53) forms a one-piece component together with one or more telescopically displaceable elongate sections (22, 24; 52, 54). Tubular bumper according to one of Claims 1 to 7, characterized in that the breaking joint (23; 53) is arranged radially between adjacent ends of the telescopically displaceable elongate sections (22, 24; 52, 54) and in the circumferential direction of the section. (22, 24; 52, 54) is continuous or intermittent. Tubular bumper according to one of Claims 1 to 8, characterized in that a spring and / or damping element (30a) which is supported between the support structure (2) and the end plate (24c) of the elongate element is used as a force transmission member. a section (24) with smaller cross-sectional dimensions, the spring and / or damping element (30a) being designed so that it can be shortened only to the maximum stroke of the bumper ram (20) during its normal operation. Tubular bumper according to one of Claims 1 to 9, characterized in that the lengths (L ₂ and L ₃ ) of the telescopically displaceable elongate sections (22, 24; 52, 54) are equally large.