RS20070065A - Truck for railway vehicles - Google Patents

Abstract

The invention relates to a truck for a railway vehicle, especially a high-speed railway vehicle, comprising a truck frame (3) and a bolster beam (4) that extends perpendicular to the direction of the truck and is used for supporting a body. One respective spring support (9) is fastened to the truck frame (3) perpendicular to the direction of the truck on both sides of the center of the truck frame by means of at least one inclined swing link mechanism that is hinged to the truck frame (3) and the spring support (9). The bolster beam (4) rests on the respective spring support (9) via at least one secondary spring mechanism. In order to increase ride comfort at high running speeds without substantially affecting the sound-proofing properties or increasing the structural height of the undercarriage, the secondary spring mechanism of the inventive truck is provided with at least one conical spring element (7) which extends across 80 to 95 percent of the distance between the bolster beam (4) and the spring support (9).

Description

SWIVEL STAND FOR RAIL VEHICLES ~~

The present invention relates to a bogie for rail vehicles, especially for high-speed rail vehicles, with a bogie frame and a cradle, which extends in the transverse direction in relation to the bogie and is used for attaching the wagon body, while on both sides of the bogie frame, in the middle - in the transverse direction in relation to the bogie, one suspension support and at least one device for swaying (guides) is fixed on the frame. bogie and suspension support, and wherein the cradle is supported via the secondary suspension on the suspension support.

One such turntable is known from document DE 27 10 983 C2. On both sides of that bogie, in the longitudinal direction of the bogie, there are leaf toothed guides intended for lateral guidance of the axle assembly, where these leaf toothed guides are connected to the wheel housing as well as to the bogie frame. The bogie frame is elastically supported on the axle assembly via the primary suspension. The wagon body rests on the cradle, which is installed transversely to the bogie frame. The cradle is attached to the suspension bracket at its ends, via the secondary suspension. The suspension bracket is further suspended by the bogie frame guide and together they are firmly connected to each other by means of a cross link.

The secondary suspension has a single intermediate support which is placed between the suspension brackets and the secondary springs. The secondary springs are supported on this intermediate support. The lower side of the intermediate support rests on a rubber-metal element, which is shaped like a conical elastic sleeve, attached to the suspension support. The secondary damper is mounted directly between the cradle and the suspension strut.

Through the supporting elements, which are attached to the suspension support with the help of intermediate supports, the acoustic connection is interrupted and removed, that is, the transmission of noise from the bogie to the wagon body is prevented. Here, special rubber-metal elements were chosen for the supporting elements, especially shaped as open conical elastic bushings, which absorb high-frequency oscillations perfectly, without major impact on the overall elasticity of the secondary suspension. Due to the installation height of the conical bush, the length of the coil springs of the secondary suspension was reduced to about 70% of the distance between the suspension support and the cradle, which also kept the acoustic resonance in a favorable frequency range.

In this way, the rigid transverse connection of both intermediate supports is externally reduced by maintaining the parallelism of the tandem springs during lateral (transverse) displacement for the sake of reducing the elastic part and increasing the displacement part, which depends on the load of the oscillator guides, placed between the suspension supports and the bogie frame (i.e., increasing the displacement in the guides thanks to the favorable effect of the installed rubber elements on the guides).

The well-known bogie still has a disadvantage, which is reflected in the relatively short coil springs in the secondary stage, due to which the stand has a very high stiffness of the secondary suspension system, which reduces driving comfort - especially at times when rail vehicles reach high speeds.

The attached invention basically has the task of providing a bogie solution that will eliminate or reduce both of the above-mentioned shortcomings to a sufficient extent and enable a simple way to improve comfort at high driving speeds, without significantly impairing the sound insulation or increasing the installation height of the chassis.

The attached invention solves this task, starting from the solution of the turntable in accordance with the above-mentioned claim 1 and in accordance with the characteristics specified in the indicated part of claim 1.

The attached invention contains technical recommendations that can be used to improve driving comfort at high speeds, without significant deterioration of sound insulation or an increase in chassis height, as it includes secondary suspension and, accordingly, coil springs, which occupy over 80%, and even up to 95%, of the distance between the cradle and the suspension support.

It has been shown that with this increase in the length of the coil spring elements and with the use of a soft spring (a spring with a low stiffness value), compared to the known bogie solution with short coil springs, driving comfort can be significantly improved precisely at high driving speeds, without significant deterioration of acoustic separation. In this case, particularly favorable characteristics are achieved, because the coil spring element extends from 85% to 95% of the total distance between the cradle and the suspension support.

While the increase in the axial length of the coil spring automatically requires the use of a spring with a soft spring characteristic, there is still the possibility of placing a flat damping element in the remaining space between the coil spring element and the suspension support, i.e. the cradle, which will be sufficient to achieve acoustic separation. The advantage is achieved by installing a suitable flat damping element between the coil spring element and the suspension support and/or between the coil spring element and the cradle in the transverse direction of the coil springs.

This damping element can be shaped into any desired, suitable shape. Preference is given to a ring or plate shape, because such shapes can be extremely easily fitted and integrated with the secondary suspension.

The damping element can basically be made from one or more suitable materials. It is especially important that it can be made from several layers of the same or different material. In order to achieve good strength and stability during a long standing time, it is necessary that at least one layer is made of rubber-based material.

A significant advantage in terms of oscillation, and particularly favorable conditions in terms of acoustics, are obtained primarily in variants of the turntable made in accordance with the invention, in which the damping element is placed longitudinally in relation to the direction of the installed helical suspension, and has an elastic stiffness of 500 N/mm to 560 N/mm, primarily from 520 N/mm to 540 N/mm.

As a further advantage in variants of the bogie made in accordance with the invention, it is provided that the damping element, placed laterally in the longitudinal direction of the built-in helical suspension, has a transverse stiffness, which is small in relation to the transverse stiffness of the helical suspension.

In this way, the damping element contributes to the overall reduction of the lateral stiffness of the built-in secondary suspension and thus increases driving comfort. In addition, the necessary lateral movement of the cradle must be ensured within the permitted limits, but not only by means of helical suspension.

A further advantage of the variants of the bogie made in accordance with the invention is that the suspension supports are firmly connected in the transverse direction of the bogie, via the lateral holding device. This makes it possible, by maintaining the suspension support in a parallel position in relation to the tandem - springs, to reduce the share of elasticity to transverse movement and increase stability using a favorable load distribution on the guides of the swaying device between the suspension support and the bogie frame.

The wobble device can, in principle, be made in the desired, convenient shape. The advantage is that the suspension support is attached to two oscillator guides, installed in the longitudinal direction of the bogie - in front and behind the secondary suspension and suspended from the frame of the bogie, resulting in a particularly simple construction.

In variants of the bogie made in accordance with the invention, a certain advantage is realized by the fact that the wheel housings of the axle assembly are connected via the primary suspension, which is fixed to the frame of the bogie in the direction of the vertical axis of the bogie, and via at least one elastic leaf device that extends in the longitudinal direction of the bogie and is attached to the frame of the bogie. A leaf spring device is composed of at least one leaf spring, which has a soft characteristic of stiffness in the vertical direction relative to the turntable. A leaf spring that has a soft stiffness characteristic makes an exceptional contribution to resolving oscillations and noise. Secondly, with soft leaf springs, problems related to strength and standing time are reduced. The required spring characteristic of the entire primary suspension can be easily adjusted using non-critical primary springs.

In the optimal variant of the bogie made in accordance with the invention, soft spring characteristics in leaf suspension, the thickness of the leaf spring in the direction of the vertical axis of the bogie is 1.05% to 1.45%, preferably from 1.15% to 1.35%, of the free spring length of the leaf spring. By reducing the thickness, the maximum stresses in the area of the upper and lower sides of the leaf spring are reduced, which also reduces the costs related to the leaf spring.

Regarding the reduced thickness of the leaf spring, it is also important to ensure sufficient strength and good lateral guidance of the axle assembly, for which it is primarily recommended that the width of the leaf spring in the transverse direction of the bogie is 32.5% to 35.0%, primarily 33.0% to 34.5%, of the free spring length of the leaf spring.

A leaf spring can, in principle, be made in any desired suitable form. Here it is possible - as an extremely simple form - to keep the same width of the leaf spring along the longitudinal axis in the derived variants. In the recommended version of the bogie, made in accordance with the invention, for especially good guidance of the axle assembly, with a favorable load distribution on the spring leaves and high load capacity, it is intended that the width of the leaf spring continuously increases in the longitudinal direction of the bogie, starting from the wheel housing towards the frame of the bogie.

Simple guidance of the axle assembly in the vertical direction of the bogie is achieved with a leaf suspension consisting primarily of two leaf springs that are placed opposite each other, in the vertical direction of the bogie.

It has been shown that a particularly favorable oscillation characteristic is obtained, when the leaf spring suspension in the direction of the vertical axis of the bogie has a stiffness of 120 N/mm to 200 N/mm, optimally from 140 N/mm to 180 N/mm.

In addition, in order to achieve an optimal ratio in terms of oscillation, it is necessary that the length of the wheel axle in the wheel bearing of the axle assembly is at least 5% greater compared to the known bogie, made according to the current state of the art. The advantage is achieved by increasing the length of the seated axle end at the wheel bearing assembly of at least one axle assembly when it is at least 6.25%, optimally 6.5%, from the center distance of the wheel bearing assembly of the first axle assembly (1). This achieves a particularly favorable ratio also in terms of load distribution.

The present invention is also concerned with rail vehicles, especially high-speed rail vehicles, with a bogie constructed in accordance with the invention.

Further advantages of the subject invention are reflected in the given sub-requirements, i.e. the descriptions given in the following text and optimal derived examples, the characteristics of which are given in the attached drawings. They show: Figure 1 is a schematic view of an embodiment of a turntable according to the invention:

Figure 2 is a schematic representation of detail II from Figure 1

Figure 1 shows a schematic view of the optimal form of the turntable 100 made in accordance with the invention with two axle assemblies 1, in the longitudinal direction of the turntable 100.1, spaced apart and attached via the bearing of the axle assembly 2 to the shoulder of the turntable 3. In the middle of the shoulder of the turntable 3 in the transverse direction of the turntable - that means normal to the plane of the drawing - there is a cradle 4, which serves to attach some - not shown in the drawing - wagon bodies.

The arm of the bogie 3 is connected via the primary suspension in the form of the primary spring stage 5 to the existing bearing housing of the axle assembly 2. Furthermore, the axle assemblies 1 are connected to the frame of the bogie 3 via the leaf suspension 6, fixed to the bearing housing of the axle assemblies 2. The leaf suspension 6 includes two leaf springs 6.1, which are placed one above the other in the direction of the vertical axis of the bogie 100.2 and in this direction provide parallel guidance of the bearing of the axle assembly 2. The leaf springs 6.1 are tightened on the shoulder of the bogie 3 and on the housing of the bearing of the axle assembly 2 using toothed plates.

The cradle 4 is attached to the secondary suspension support 9, on both longer sides of the bogie 1 through the secondary suspension 7 and the secondary damping device 8. As shown in Figure 2, the secondary suspension 7 includes the spring element 7.1 and the damping element 10. The secondary suspension support 9 is connected to the frame of the bogie via two oscillator guides 11, which are placed in the longitudinal direction. of the turntable 100.1 in front of and behind the secondary suspension 7, suspended from the frame of the turntable 3.

The spring element 7.1 along its longitudinal axis 7.2 is composed of two - one inside the other - coaxial coil springs in the so-called elastic - tandem design. The coil spring element 7.1 extends in the direction of the vertical axis of the bogie 100.2 with a length L, which occupies 85% of the distance D between the cradle 4 and the secondary suspension support 9.

The coil spring element 7.1 is attached to the cradle 4 with its upper end. The coil spring element 7.1 is connected with its lower end via the damping element 10 to the secondary suspension support 9.

The damping element 10 is a flat element placed in the direction of the longitudinal axis 7.2, which means that it performs a certain expansion in the direction of the longitudinal axis 7.2, which is negligible compared to its expansion in the direction transverse to the longitudinal axis 7.2. Damping element 10 is made in a ring shape. Its central part 10.1 consists of an elastic rubber material, which is tightly clamped by two circular metal plates 10.2. The damping element has an elastic stiffness of 530 N/mm in the direction of the longitudinal axis 7.2 of the built-in helical spring element 7.1, which resulted in favorable characteristics of forced oscillations, as well as particularly favorable acoustic characteristics.

Here, it was shown that by extending the coil spring element 7.1 with a soft spring characteristic compared to the known bogie solution with short spring elements, a significant improvement in driving comfort can be achieved at high speeds, without worsening the acoustic separation.

Thus, the increased axial length of the coil spring element 7.1 entails a soft spring characteristic of the secondary suspension 7. At the same time, in the remaining space between the coil spring element 7.1 and the secondary suspension carrier 9, flat damping elements 0 are installed, which achieves sufficient acoustic separation.

In this case, it is understood that in other variants of the invention, a damping element can also be installed between the coil spring element and the cradle. It is also understood that one suitable damping element can be installed at both ends of the coil spring element. Furthermore, the damping element can be installed in some other way. In all of this, it is particularly important that the plate-shaped damping element can be made of several layers of the same or different material.

The damping element 10 has a certain transverse stiffness, transverse to the longitudinal axis 7.2 of the installed coil spring elements, which is small in relation to the transverse stiffness of the coil spring element 7.1. By means of this, the damping element contributes to the reduction of the overall transverse stiffness of the secondary suspension 7 and thus to the increase of driving comfort.

Furthermore, the necessary transverse free movement of the cradle 4 must be achieved, which is different from known turntables with built-in intermediate supports and short springs, where it is not possible to achieve the required movement through short transversely rigid elements. Moreover, the required transverse movement of the cradle can be realized through the transverse deformation of the secondary suspension 7 almost the entire length of the distance D, so that the loads of individual parts are reduced to a favorable value.

The supports of the secondary suspension 9 are firmly connected in the transverse direction of the bogie via a transverse holding device. Here it is possible, by maintaining the secondary suspension support 9 in a parallel position, to reduce the excess elasticity of the coaxial springs during lateral movement and, depending on the load, to increase the useful guidance between the secondary suspension support 9 and the bogie frame 3 by means of the rocker device 11.

Furthermore, increased comfort can be achieved if the leaf springs 6.1 of the spring device 6 have a soft spring characteristic in the direction of the vertical axis of the turntable 100.2. In the attached case, the spring device 6 has a spring stiffness of 160 N/mm in the vertical direction of the turntable 100.2.

The soft leaf spring 6.1 achieves positive characteristics in terms of oscillations and noise. In addition, this soft spring device 6 reduces problems related to firmness and dwell time. In doing so, the required spring characteristic of the overall secondary suspension is simply regulated by choosing a non-critical primary suspension 5 with respect to stiffness and dwell time issues.

In order to achieve these favorable characteristics, the thickness of each individual spring leaf 6.1 is, in the vertical direction of the turntable 100.2, about 1.25% of the free spring length of the leaf spring 6.1. By reducing the thickness, the maximum stresses in the area of the upper and lower sides of the leaf spring 6.1 are reduced, which also reduces the costs related to the maintenance of the leaf spring 6.1.

In order, when the thickness of the leaf spring 6.1 is reduced, to also achieve sufficient strength and good lateral guidance of the axle assembly 1, the width of the leaf spring 6.1 in the transverse direction of the bogie, which means transverse to its longitudinal axis, should be about 33.75% of the free length of the LD leaf spring 6.1. The leaf spring 6.1 has, along its longitudinal axis, the same continuous width along its entire length.

In other variants of the bogie, performed in accordance with the invention, with particularly good lateral guidance of the axle assembly, favorable distribution of the load in the leaf spring and a high degree of durability of the structure, it can also be achieved by optimizing the cross-section of the leaf in relation to the load with a continuous section or by varying the thickness of the section and/or the width over the entire length of the leaf spring. It is particularly advantageous when the width of the leaf spring continuously increases in the longitudinal direction of the bogie from the wheel bearing housing towards the frame of the bogie.

The wheel housing 2 of the axle assembly 1 includes the wheel bearing assembly, in which the wheel axle is mounted. In relation to the current center of the load distribution, a favorable value is achieved if the length of the wheel axle housing in the wheel housing 2 of the axle assembly 1 is increased by 5% compared to the length of the housing in previously known bogies made in accordance with the current state of the art. The length of the existing wheel axle bearing is increased here to 6.5% of the center distance of the wheel bearing assembly of the axle assembly 1. This results in a particularly favorable ratio for the bogie 100, from the point of view of load distribution.

In the remaining part, an extended family of turntables based on the turntable 100 is described. Thus, the frame of the turntable 3 is made in the "H" form of the frame with two longitudinal and two transverse supports without a separate crosshead support. The attachment of the wagon body is provided via four sliding plates placed laterally on the cradle 4 between the transverse supports of the bogie frame 3. A pivoting wedge is placed on the wagon body for its longitudinal fixation and centering in the cradle 4. A mechanical winding damper is provided to stabilize the bogie when moving on rails at speeds over 160 km/h. It is realized in the form of a torsion shaft hinged on the cradle 4, which is attached via two levers to the frame of the turntable 3. It prevents excessive unauthorized movement of the frame of the turntable 3 in relation to the cradle 4 in the event of a large longitudinal movement, for example, when the springs are completely unloaded. That's what the sliding plates are for, placed between the cradle 4 and the wagon body. It turned out that the movement of the cradle 4 in relation to the bogie frame 3 in the direction of travel, thanks to the mechanical winding damper, amounts to only a few millimeters (with a favorable design, it is between +/- 4mm and +/- 6mm).

The turntable 100 also has a large base for mounting the suspension (more than 2,500 mm), which achieves great stability during swaying.

By means of the guides of the wobble device 11 mounted in concentric rubber elements - bushings - it is possible to increase the length of the wobble and increase the return force for suffocation of the wobble. Cradle 4, in terms of achieving optimal comfort, has a relatively large movement transverse to the direction of travel in relation to the frame of the bogie 3. In the versions that are considered advanced, this movement is between +/- 50 mm and +/- 70 mm.

Depending on the quality of the railway track, the lateral movement of the cradle must be limited via eccentrically installed lateral movement stops on the bogie frame, which fit with the corresponding structural elements on the wagon body. There are also elastic stops between the cradle 4 and the frame of the turntable 3, placed in the longitudinal and transverse directions.

Secondary damping in the vertical direction is achieved through a hydraulic shock absorber 8 installed between the secondary suspension support 9 and the cradle 4 and placed between the secondary suspensions 7.

The primary suspension 5 is realized through a coil spring assembly composed of an inner and outer spring placed on the bearing housing of the axle assembly 2. The primary damping is performed by means of a hydraulic shock absorber, placed in parallel next to the mentioned primary spring. When assembling axle assemblies 1, adjustable roller bearings are used, whereby the outer ring of the bearing is placed in the part of the wheel housing intended for the rolling bearing and the bearing cup is fixed over the inner ring that is screwed from the outside, which creates the necessary gap for proper rotation of the bearing and ensures parallel rotation and good guidance of the wheel.

Additional rubber-metal elements integrated into the primary and secondary suspension and leaf guide 6 of the axle assembly, as well as rubber elements on the guides of the wobble device 11, are used for acoustic insulation and vibration isolation.

The braking system is an axle drum brake with an appropriate number of brake discs, and for trains that reach speeds over 160 km/h, an additional magnetic brake is provided that acts on both rails.

The usefulness of the solution made in accordance with the invention is also reflected in other advantages, not only in driving comfort and driving stability. This utility is also shown in the solution made in accordance with the invention and through the increase in convenience for assembly and maintenance.

Claims (15)

1. A bogie for rail vehicles, especially for high-speed rail vehicles!- with one frame of the bogie (3) and with a cradle (4), which extends in a transverse frame, on the longitudinal axis of the bogie and is used for tying the wagon body, indicated by, that the suspension supports (9) are installed on the frame of the turntable (3) in the transverse in the direction relative to the longitudinal axis of the bogie, on both sides relative to the center of the bogie frame, and fixed by means of at least one rocking device that is mounted on the bogie frame (3) and the suspension support (9), indicated by the fact that cradle (4) fixed via at least one secondary suspension to the carrier suspension (9), indicated by that secondary suspension, consisting of at least one coil spring element (7), occupies over 80% to 95% of the space between the cradle (4) and suspension bracket (9). between the coil spring element (7) and the suspension support (9) and/or between between the coil spring element (7) and the cradle (4) in the longitudinal direction of the coil spring element (7), a flat damping element (10) is installed. indicated by that. yes damping element (lO) in the direction transverse to the longitudinal axis of the spring elements (7) shows a transverse stiffness, which is lower than the transverse stiffness of the coil spring elements (7). 2. The turntable according to claim 1, characterized in that the coil spring element (7) extends over 85% to 95% of the distance between the cradle (4) and the suspension support (9). 3. Rotating base according to claim 1 or 2, characterized in that the damping element (10) is made in the form of a ring or a plate. 4. A rotating base according to one of the previous requirements, characterized in that the damping element (10) has at least one layer made of rubber material. 5. A rotating base according to one of the previous requirements, characterized in that the damping element (10) has a stiffness of 500 N/mm to 560 N/mm, primarily from 520 N/mm to 540 N/m in the longitudinal direction of the coil spring elements (7). 6. The turntable according to one of the preceding claims, indicated by the fact that the suspension supports (9) are firmly connected in the transverse direction of the turntable via the device for lateral connection. 7. A bogie according to one of the previous claims, indicated by the fact that the suspension support (9) is suspended from the frame of the bogie (3) via two wobble devices, placed in the longitudinal direction of the bogie in front of and behind the existing secondary suspension. 8. A turntable according to one of the previous requirements, indicated by the fact that the wheel bearing housing (2) of at least one axle assembly (1) is over at least one elastic leaf device (6), which extends in the longitudinal direction of the turntable, in the direction of the vertical axis of the turntable supported on the shoulder of the turntable, wherein the leaf device (6) has at least one leaf spring (6.1) with a soft spring characteristic in the direction of the vertical axis turntable. 9. The turntable according to claim 10, characterized in that the thickness of the leaf spring (6.1) in the direction of the vertical axis of the turntable is 1.05% to 1.45%), preferably 1.15% to 1.35%, of the free spring length of the leaf spring (6.1). 10. The turntable according to claim 8 or 11, characterized in that the width of the leaf spring (6.1) in the transverse direction of the turntable is 32.5% to 35.0%, preferably 33.0% to 34.5%, of the free spring length of the leaf spring (6.1). 11. The turntable according to claim 10, characterized in that the width of the leaf spring (6.1) decreases in the longitudinal direction of the turntable in the direction towards the wheel bearing housing (2). 12. A turntable according to any claim 10 to 13, characterized in that the leaf device (6) includes two leaf springs (6.1) placed one above the other in the vertical direction of the turntable. 13. The turntable according to one of claims 8 to 12, characterized in that the leaf spring device (6) has a stiffness of 120 N/mm to 200 N/mm, preferably from 140 N/mm to 180 N/mm, in the direction of the vertical axis of the turntable. 14. The turntable according to one of the preceding requirements, characterized by the fact that the wheel bearing housing (2) of at least one first axle assembly (1) has a wheel bearing assembly and that the length of the wheel axle in the first axle assembly (1) is at least 6.25%. primarily 6.5%, from the middle distance of the wheel bearing assembly of the first axle assembly (1). 15. Rail vehicles, especially high-speed rail vehicles, with one bogie according to some of the previous requirements.