RU203994U1 - Energy absorption unit - Google Patents

Abstract

The utility model relates to railway engineering, more precisely to structural elements of buffer and coupling devices with shock absorption by permanent deformation of the buffer element. An energy absorption unit (crash device) is proposed, suitable for use in coupling devices, containing a deforming element (matrix) with a tapering hole and a tubular crash element equipped with a thread, the end of which is threaded into the opening of the deforming element and secured by a threaded locking element, in which a retaining element is installed inside the end of the crash element to increase the tensile strength, preventing a decrease in its inner diameter. was made in the form of a disk with a hole and installed in the bore of the end part of the crash element at a distance (0.2 ... 0.5) from the end of the threaded end of the crash element. In addition, for an even greater increase in strength, the end of the locking element entering the deforming element and the mated surface the spine of the deforming element can be made conical, and the conical surface of the end of the locking element is made as an outer cone.

Description

The utility model relates to railway technology, more precisely to the structural elements of buffer and coupling devices with shock absorption by permanent deformation of the buffer element.

In this description, the terms will be used in the following interpretation:

- deforming element: a part or assembly that directly acts on a crash element to deform it in order to absorb collision energy; for brevity, it will be referred to as a matrix hereinafter. In the prior art, the equivalent name "die" is found;

- crash element: an irreversibly deformable part, the deformation of which requires collision energy;

- outer cone: sign "outer": according to GOST 25557-2006;

- ultimate strength: the maximum mechanical force that stretches the energy absorption node that can be applied to it before it starts to break;

- spring flat thrust ring: according to GOST 13943-86;

- reduction: reducing the size of the outer contour of the pipe (New Polytechnic Dictionary / M .: "Big Russian Encyclopedia", 2000);

- energy absorption device: according to GOST 32410-2013.

A buffer energy absorption device is known containing a deforming element, or matrix, with a tapering hole and a tubular crash element, fixed in it by a tight fit along conical mating surfaces, having a conical taper at one of its ends, passing into a cylindrical section, partially protruding beyond the outlet part matrix [RU 176226]. Upon collision, the crash element is pushed through the matrix, reducing its diameter (reducing) and thereby absorbing the collision energy. The known device can be used in dead-end or shock-resistant devices (buffers), that is, where the force can be directed only to compress the crash element. For use in coupling devices, where the forces can be both compressive and tensile, the known buffer device is unsuitable, since it cannot transmit the traction force from the coupling to the car frame.

Known energy-absorbing device for the protection of rolling stock. It includes an energy absorption unit, consisting of a matrix and a crash element fixed in it, made in the form of a cylindrical pipe, having a conical narrowing at one of its ends, passing into a cylindrical section, partially protruding beyond the output part of the matrix. A ring is put on this section and welded to it, which does not allow the unit to disintegrate under the influence of tensile forces [RU 174223].

The tensile strength of a known knot can be quite high, but it is designed to accept only compressive forces. For use in coupling devices experiencing both compressive and tensile forces, it is of little use, since during long-term operation of the coupling device, which would include the described unit, under the influence of alternating loads in the weld and the surrounding heat-affected zone, defects begin to accumulate, with time leading to the destruction of the seam and rupture of the assembly and the coupling device.

The closest to the proposed in technical essence and the achieved result is a device for absorbing the kinetic energy of an emergency collision, intended for use in clearance-free coupling devices, containing an energy absorption unit, consisting of a matrix with a tapering hole and a crash element fixed in it, made in the form of a cylindrical pipe having a conical taper at one of the ends, passing into a cylindrical section, partially protruding beyond the outlet part of the matrix. This section is provided with a thread, onto which a threaded locking element (shaped nut) is screwed, abutting with its straight, flat end against the bore of the matrix [RU 176272].

Replacing the welded ring with a nut made it possible to avoid failures caused by the destruction of the welded seam under alternating loads, but the tensile strength of the assembly, which determines its reliability, turns out to be insufficient.

In the known unit, the maximum load falls on the threads closest to the point of contact of the nut end and the bore of the matrix. The impact on them of axial tensile forces due to the compliance of the free end of the crash element protruding beyond the output part of the matrix, leads to a partial exit of the threads of the crash element from the turns of the nut, and this part of the thread almost ceases to perceive the load, shifting it to the already loaded loops closest to the nut end.

Due to the uneven distribution of the load, with the occasional extreme thrust forces, the most loaded turns break off. The load is transferred to subsequent turns, also broken off after a short time. After the failure of the threaded connection, the assembly loses the ability to transmit tractive forces, the coupling device breaks.

The objective of this utility model is to create an energy absorption unit that has an increased tensile strength when exposed to tensile forces and, due to this, a longer service life under conditions of alternating loads typical of coupling devices.

The technical result of using the proposed energy absorption unit is to increase its ultimate strength to tensile forces, which increases the MTBF of the unit itself and the coupling device into which it enters.

The specified technical result is achieved by the fact that in the known energy absorption unit containing a deforming element with a tapering hole and a tubular crash element equipped with a thread, the end of which is threaded into the hole of the deforming element and secured with a threaded locking element, a retaining element is installed inside the said end to prevent reduction its inner diameter.

In addition, the end part of the crash element has a bore in which the retaining element is installed.

In addition, the distance from the flat surface of the bore to the end of the threaded end of the crash element is (0.2 ... 0.5) the length of the threaded section.

In addition, the retaining element is secured in the crash element by a spring-loaded flat thrust ring.

In addition, the retaining element has a through hole.

In addition, the retaining element is made in the form of a disk.

In addition, the retaining element is installed coaxially with the crash element tube.

In addition, the locking element is made partially included in the bore of the deforming element, and its end part and the surface of the deforming element mating with it are made conical, and the conical surface of the end of the stopping element is made as an external cone with an angle between the generatrix and the axis in the range (40 ... 70) °.

Due to the introduction into the structure of the energy absorption unit of a retaining element installed inside the end of the crash element equipped with a thread, the tensile strength of the unit under conditions of alternating loads increases, which allows it to be included in the coupling devices.

By equipping the end of the pipe of the crash element with a bore and installing a retaining element in it, the tensile strength of the unit increases due to the precise installation of the disc in the pipe. It also simplifies the assembly process of the subassembly.

When installing the retaining element in the bore, the flat surface of which is located at a distance (0.2 ... 0.5) of the length of the threaded section, from the end of the threaded end of the crash element, the greatest resistance of the thread to shear under the influence of extreme loads is achieved, that is, the limit increases the strength of the knot, since this ensures an even distribution of the load over all threads.

Due to the fastening of the retaining element in the pipe of the crash element with a spring flat thrust ring, the tensile strength of the assembly increases in comparison with other methods of fastening that weaken the assembly.

Thanks to the through hole in the retaining element, ventilation of the cavity of the crash element pipe is improved, which, by preventing corrosion, contributes to an increase in the service life of the unit. The hole also makes it easier to install the retaining element in the sharpening.

Due to the implementation of the retaining element in the form of a disk, its manufacture is simplified and cheaper, and the claimed technical result is achieved with its minimum weight.

Due to the installation of the retaining element coaxially with the crash element pipe, the ultimate strength of the energy absorption unit is increased due to the azimuthally symmetric distribution of the load on the disk from the side of the deformable crash element pipe.

Due to the implementation of the stop element end face entering the deforming element and the mating surface of the deforming element conical with an angle between the generatrix and the axis in the range of (40 ... 70) ° when a tensile force is applied to the unit, a force radially directed to the axis is created, contributing to the mutual compression of the threads on the entire height of the profile and a more even distribution of the load along the threads, which increases the tensile strength of the unit.

The essence of the utility model is illustrated by a drawing, which shows a section of the proposed node by a plane passing through its axis.

The main elements of the proposed energy absorption unit are the crash element 1 and the deforming element 2, which will be called the matrix for brevity. The crash element is a pipe 3, one end of which is reduced to a cone 4 with the formation of a mouthpiece 5 at the end part and is tucked into the tapering hole of the matrix 2. This hole can have tapered walls in its simplest design, but it can also have a more complex profile, for example, parabolic ...

To fix the crash element 1 in the matrix 2, its muzzle 5 is equipped with a thread 6, onto which a locking element 7 is screwed, which is made in the form of a sleeve with an internal thread (shaped nut), the end of which partially enters the bore 8 of the matrix 2. The end face facing the matrix part of the locking element 7 can be made conical so that its surface 9 is the lateral surface of a truncated outer cone with an angle α between the generatrix and the axis of the cone, preferably lying in the range (40 ... 70) °. Accordingly, the surface of the matrix 2 mating with it must also be made conical, like the surface of a truncated inner cone. From the opposite end of the matrix 2 the locking member 7 may have structural elements that facilitate its tightening, for example flattenings on the side surface or splines on the p tse.

The locking element is tightened along the thread 6 so that its end part is in close contact with the bottom of the bore 8 of the matrix 2. Considering that the diameter of the crash elements lies within (120 ... 220) mm, such locking is strong enough to to withstand the towing force from the hitch. Such fastening gives the energy absorption unit the ability to resist not only compressive but also tensile forces, that is, makes it suitable for use in coupling devices.

In the assembled energy absorption unit, the tightened locking element 7 is connected to the thin end of the pipe 3 by a non-standard weld 10. The purpose of the seam 10 is to prevent the locking element 7 from unscrewing, and it can be made intermittent. He does not perceive the traction load from the coupling device, and therefore he is not afraid of alternating loads.

Inside the narrow end of the pipe 3, in close contact with the walls of the pipe, a retaining element 11 is installed coaxially with it, which prevents a decrease in the inner diameter of the narrow end of the pipe under the influence of axial tensile loads on the assembly. It can be made, for example, in the form of a short section of a rod or a thick-walled sleeve, and also, as shown in the drawing, in the form of a disk. The retaining element 11 may have at least one through-hole 12 to prevent corrosion of ventilation of the interior of the pipe 3 and to facilitate installation. For a more accurate installation of the retaining element inside the pipe 3, a boring can be made. The retaining element 11 must be fixed inside the pipe 3, for example with a spring flat stop ring 13. Fixation by welding, even at individual points, is undesirable, since it changes the mechanical properties of the pipe and the retaining element.

When installing the retaining element 11 in the bore of the pipe 3, it is preferable that the distance l from the flat surface (bottom) of the bore, to which the retaining element is pressed and from which its retaining action begins, to the end of the threaded end of the crash element was in the range l = (0, 2 ... 0.5) L, where L is the length of the threaded section. It is in this range that the distribution of the load along the length of the threaded section, as follows from the results of calculations and strength tests, is the most uniform.

The energy absorption unit can also include elements that serve to ensure the possibility of articulation with parts of the coupling device. Thus, the pipe 3 can be fastened at its free end to a flange or sleeve 14, and the outer surface of the matrix 2 can have a groove 15 for gripping the assembly with clamps connecting the parts of the coupling.

The proposed node works as follows.

In the event of collisions, the pipe 3 of the crash element 1 is pressed into the hole of the die 2. The deformation work performed during this process absorbs the collision energy, reducing the negative acceleration and thereby reducing the undesirable effect on passengers and rolling stock.

With tensile forces on the knot, both from traction and from jerks, the bottom of the bore 8, acting on the end part of the locking element 7, loading the threads closest to it, creates a force that, due to its pliability, tends to pull the end of the pipe 3 to its axis and unload threads closest to the end of pipe 3, which poses a threat of thread breakage. However, the retaining element 11 prevents the tightening of the end of the pipe 3 and the unloading of the threads closest to its end. The distribution of the load along the threads becomes more uniform, and the tensile strength of the assembly increases, as shown by tests, by (23 ± 4)% compared to the declared utility model , which does not have a retaining element.

Even more contributes to the increase in the load resistance of the connection, the design of the mating surfaces of the locking element and the matrix is conical, since the conical surface 9 of the end of the locking element 7, resting on the conical surface of the associated bottom of the groove in the matrix, seeks to compress the thread of the locking element 7 around the pipe 3, the area of interaction of the threads and reducing the specific load on them.

Claims (8)

1. An energy absorption unit containing a deforming element with a tapering hole and a tubular crash element equipped with a thread, the end of which is threaded into the hole of the deforming element and secured with a threaded locking element, characterized in that a retaining element is installed inside the said end to prevent a decrease in its inner diameter ... 2. The energy absorption unit according to claim 1, characterized in that the end part of the crash element has a bore in which the retaining element is installed. 3. The energy absorption unit according to claim 1, characterized in that the distance from the flat surface of the bore to the end of the threaded end of the crash element is (0.2 ... 0.5) the length of the threaded section. 4. The energy absorption unit according to claim 1, characterized in that the retaining element is fixed in the crash element by a spring flat thrust ring. 5. The energy absorption unit according to claim 1, characterized in that the retaining element has a through hole. 6. The energy absorption unit according to claim 1, characterized in that the retaining element is made in the form of a disk. 7. The energy absorption unit according to claim 6, characterized in that the disk is installed coaxially with the crash element tube. 8. The energy absorption unit according to claim 1, characterized in that the end face of the stopper element entering into the deforming element and the surface of the deforming element mating with it are made conical, and the conical surface of the end face of the stopping element is made as an outer cone.

Images