FI82423B - Friction-damping construction - Google Patents

Abstract

A damping construction for damping, by friction work, shocks or vibrations which strike wheels or wheel sets in a rail vehicle provided with an articulated bogie or wheel suspension with traction arms, which friction work is generated between the frame of the vehicle and another construction part in dependence upon the load F and the spring play. The first friction surface 18a, 18b of the damping construction lies in a fixed projection 19a, 19b of the traction arm or the wheel body part of the bogie at a distance S from the axial line 17a, 17b of the wheel or wheel set and the second friction surface 21a, 21b has been formed between the end 20a, 20b for the spring of the vehicle or another resilient element 9a, 9b and the first friction surface. <IMAGE>

Description

1 82423

Kitkavaimennusrakenne

The invention relates to a damping structure for damping shocks or vibrations on the wheels or wheel sets of a rail vehicle equipped with an articulated bogie 5 or a wheel support based on support arms by friction work generated between the vehicle and another component as a function of load force and elastic travel. In particular, the invention 10 relates to a damper structure at least partially in the bogie of a rail vehicle suspended by leaf springs.

In vehicles, shock absorption can generally be implemented in a wide variety of ways. The most common shock-absorbing structures are gas and liquid shock absorbers. When considering a rail vehicle, and in particular the suspension of a freight wagon, the disadvantage of such shock absorbers is that their damping is typically constant. Because there is a significant difference between the unladen weight and the laden weight of a freight wagon, shock absorbers of this type are not well suited for this application because in practice they act as too strong shock absorbers with an empty wagon and too soft shock absorbers with a fully loaded wagon. In addition, these types of shock absorbers are expensive and maintenance-intensive, which is why they are also not often used in freight wagons.

Often the suspension of freight wagons is implemented with a multi-leaf leaf spring, whereby a relatively useful result is achieved with a simple structure. First, the leaf-spring structure is inexpensive, and in addition, the interfaces between the leaves of the spring act relative to each other during movement as a load-dependent friction shock absorber. For this reason, among others, this is the most common 35 Suspension type in freight wagons. In the case of leaf springs, friction can be generated not only between the leaves of the spring but also between the spring head and the fixed component, as described, for example, in DE-2 842 211. In the construction of this publication 2 82423, a leaf spring or a leaf spring pack is attached to the axle or bogie once and for all, and at the ends of the spring there are compression pieces which move against the lower surface of the carriage body.

5 Although the leaf spring structures described above, in principle, act as friction dampers, they are not sufficiently effective, especially in the case of high-speed driving, in which the shocks and vibration-generating forces are large. Thus, when constructing, for example, a bogie for a freight wagon, which must be able to travel at a higher speed than the current ones, a known separate shock absorber structure, such as gas or liquid shock absorbers or other shock absorber structures of complex construction, must be used with current technology. In particular, due to the driving characteristics of the carriage, the structure of said publication DE-2 842 211 is not suitable as a starting point, as it does not allow the bogie parts to turn relative to one another, due to the riding characteristics of the carriage, which is articulated or radially self-steering.

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The object of the invention is thus to provide a damping structure which reduces shocks and vibrations, the damping of which is load-dependent, so that the damping is lower at low load and higher at high load. In addition, it is an object of the invention to provide a damper structure which operates in a hingedly connected radially steered or steered bogie in which the parts of the bogie body pivot and rotate considerably relative to each other. It is also an object of the invention to provide a damper structure having a damping power substantially higher than that of conventional friction dampers. It is a further object of the invention to provide a damping structure which dampens movements in the bogie and carriage in all directions, i.e. substantially vertical movements in the direction of gravity, e.g. horizontal movements due to track roughness 35 and radial movements of the bogie due to track curvatures. and still dampens the so-called. blue hunting (hunting- 3 82423 vibrations) in which the wheel set rotates back and forth about its vertical axis. It is a further object of the invention to provide such a damper structure which is simple in construction, inexpensive and low in maintenance.

5

The structure according to the invention provides a decisive improvement in the above-mentioned drawbacks and achieves the objectives defined above, and in addition the damper structure acts as a load-bearing suspension. To achieve this, the device according to the invention is characterized by what is set forth in the characterizing part of claim 1.

The main advantages of the invention are that it provides a load-dependent efficient shock absorber and vibration damper for a rail vehicle, without the need for any additional shock absorbers. Another advantage of the invention is that the structure is simple and reliable and does not require expensive structures.

In the following, the invention will be explained in detail with reference to the accompanying drawings.

Figure 1 shows the bogie structure according to the invention in a schematic side view in a perspective view.

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Figure 2 schematically shows an embodiment of a friction damper according to the invention.

Figure 3 shows another embodiment of a friction damper.

Figure 1 shows an overview of a bogie 1 according to the invention, comprising two wheel body parts 2 and 3, in each of which wheel rims 4 and 5 are placed. The support frame 35 6 comprises a cross beam 7 and side beams 8a and 8b. The side beams 8 and the cross beam 7 are rigidly attached to each other and rest on springs 9a, 9b or spring packs 9c, 9d on the wheel body parts 2 and 3 so that the carriage load F coming through the springs 4 82423 is applied to the wheel body parts at least approximately through the axle line 17. in a vertical plane. The carriage body, not shown, is connected to a bogie center 10, 5 on top of the cross member 7, which is of a standardized type of known construction. When tilted, the carriage body corresponds to the side supports 11a, 11b.

The wheel body parts 2 and 3 consist, for example, of a horizontal U-shaped body body with side parts 10a 14a, 14b and 15a, 15b, respectively, and a transverse base part 12a and 12b, respectively. The body pieces are connected to each other by their joints 12a and 12b in a vertical plane passing through the center line of the carriage. This coupling joint 13 is designed to allow the wheel body parts 15 2 and 3 to pivot relative to each other both horizontally and vertically and, in addition, to allow the wheel body parts 2 and 3 to rotate relative to each other around the longitudinal line of the carriage. There are several types of such joint structures, so it will not be described in more detail here. The wheel-20 folds 4 and 5 or the wheels, respectively, are rigidly mounted on the arms 14a, 14b, 15a, 15b of each U-shaped frame beam so that the rolling direction becomes parallel to the arms. Thus, the parts 2 and 3 of the wheel frame form a bogie structure with radially steerable wheel-25 folds connected.

The wheel frame parts 2 and 3 are connected to each other resiliently in the vicinity of the second side pair 14a, 15a of the U-shapes of the frame bodies and likewise in the vicinity of the second side pair 14b, 15b by two substantially similar stable structures, generally indicated by reference numeral 16.

The two stabilizing structures 16 are further articulated to the side beams 8a and 8b of the support frame 6, respectively. Each stabilizing structure 16 is constructed so as to allow, when considering the movement of the wheel body parts 2 and 3 relative to each other, these side edges 14a and 15a or 14b and 15b, respectively, to move in the direction of travel and vertically of the bogie at least slightly relative to each other. Each support structure is articulated to the longitudinal beams 8a and 8b of the support frame 6 so that the support frame 6 and the wheel frames 2, 3 can move horizontally relative to each other. The structural combination described above allows the coupling joint 13 to be sensitive and without stiffening structures.

Figure 2 shows how, according to the invention, the first friction surfaces 18a and 18b are arranged in each of the wheel body parts 2 and 3 at a distance S from the axis line 17a, 17b of the wheelsets 10. In this case, when the side portions 14a and 15a and, of course, the invisible side portions 14b and 15b on one side, respectively, are approximately horizontal and the load force F is applied as spring compression components to these wheel body portions from approximately the vertical direction, the surfaces 18a, 18b are approximately horizontal and approximately vertically, i.e. perpendicular to the side portions 14a, 15a. In general, the distance S is at least approximately parallel to the direction of action of the load force F or its component 20 at the point where the force or the force component, respectively, meets the protrusion 19a, 19b of the wheel body part or the support arm. The first friction surfaces 18a, 18b are also at least on average perpendicular to the compressive component P of the load force F at the point of action of this component P on each of the projections 19a and 19b. In this case, a single-leaf leaf spring is selected as the spring of the vehicle, e.g. a parabolic leaf spring 9a and on the other side of the vehicle 9b respectively, fixed in the middle to the support frame 6 and having ends 20a, 20b 30 extending over the first friction surfaces 18a, 18b. The springs 9 are thus curved so that their center 23 at the support body 6 is vertically or generally in the direction of the force F, substantially higher than the ends 20 of the spring.

The spring thus descends unloaded from the center to the sides 35 and down towards the first friction surfaces. Second friction surfaces 21a and 21b are formed on the lower surface of the spring ends 20a and 20b, which abut against the first friction surfaces 18a and 18b, respectively. In this case, when there are a total of four friction surfaces 6,82423 and the springs 9a, 9b carry the entire load force F, the compressive forces P between each of the first and second friction surfaces are approximately one-fourth of the total load force F and parallel to it.

In the structure of Fig. 1, the load force F is distributed to the load-bearing spring pack 9c, 9d and the spring 9a, 9b acting on the friction surfaces in the desired ratio by suitable sizing of the springs 9a, 9b and 9c, 9d, the compressive force P being correspondingly smaller than in the structure shown in Fig. 2.

When, for example, in the described friction damping structure, the load force F increases either due to an increase in load or as the carriage travels under the influence of acceleration forces caused by irregularities, the support frame 6 at some point depresses the corresponding spring. As a result, the joint 13 also moves down the same distance under the action of the stabilizing structure 16, as shown by the arrows A in Fig. 2. This causes the side portions 14a and 15a to pivot about the axis lines 17a and 17b. Since the projections 19a and 19b are fixed parts of the side portions 14a and 15a, the friction surfaces 18a and 18b at these projections at the distance S from the axis line move by the same angle of rotation towards the support body 25 6, i.e. in the direction of the arrows B. This displacement in direction B is slightly further enhanced by the reduction in distance corresponding to the reduction in the horizontal projection of the side portions 14a and 15a as these portions turn from a horizontal position to an oblique position due to rotation in direction A, bogie axle lines 30a and 17b converging. At the same time, the curvature of the leaf spring decreases from the center under the load force F, i.e. the spring 9a straightens because its ends 20a and 20b remain at a constant height due to the projections 19a and 19b. In this case, the ends 20a and 20b of the spring 9a and thus also its friction surfaces 21a and 21b move outwards in the direction of the arrows C. Thus, under the action of the compressive component P caused by the load force F, the friction surfaces 18a and 21a and 18b, 21b, respectively, move due to the increase in load for a considerable distance which is substantially greater than that achieved in the prior art structures 5. Since the friction work is determined by the compressive force of the coefficient of friction and the result of the travel made against the friction, a considerably high friction work power is thus achieved. The opposite momentary change in load or acceleration force naturally moves the surfaces 18a, 21a and 18b, 21b 10, respectively, in opposite directions to the recent one. Thus, for example, the oscillation is damped by a factor, the magnitude of which depends directly on the stationary value of the load and the amplitude of the oscillation.

Friction work can be influenced by the bogie dimensioning, whereby reducing the wheelbase V and increasing the length S of the projection 19a, 19b increase the movement of the first surface 18a, 18b in direction B. This is because the same elasticity A causes an increased lever angle V / due to the lever arm ratio and lengths. 2 and S for a stronger decrease in the horizontal projection of the arm V / 2. In this case, the movement of the second friction surface 21a, 21b in the direction C and against it can be influenced by the curvature of the spring 9a, i.e. the coupling point of its center 23, and the vertical height difference H between the ends 20a, 20b 25. The movement of the spring ends 20a, 20b can be maximized.

If the center 23 of the spring is located below the ends 20a, 20b of the spring, i.e. the spring 9a, 9b is curved downwards, 30 as in the bogie structure shown in Fig. 3, the horizontal movements and the inclination of the bogie to hunting are damped. In this case, the vertical movements in the direction of the load force F are damped mainly by the internal friction of the spring packs 9c, 9d and only to a small extent by the spring 9a, 9b 35 on the friction surfaces 18a, 18b, 21a, 21b. With this constructed bogie, a particularly low but still very damped bogie is obtained.

82423 By arranging the first surfaces 18a and 18b large enough with respect to the movement of the wheel body parts 2, 3 as they guide radially, rotate relative to each other and the support frame moves forward or backward 5 or either side relative to the wheel body by driving forces so that the spring ends 20a, 20b 21a and 21b remain on said first surfaces 18a, 18b, the structure according to the invention dampens all the above-mentioned movements in a corresponding manner. This possibility of movement is clearly seen in Fig. 1, in which the edges 22a-d of the surfaces 18 are arranged so that the ends 20 of the springs 9 with their friction surfaces 21 always remain on said surfaces 18. Thus, the friction work between the surfaces 18 and 21 dampens the movements both in the vertical direction PS in all horizontal directions 15 VS, in the direction of rotation KS relative to each other and in the direction of radial rotation RS of the wheel body parts relative to each other. In addition, the friction damping according to the invention dampens the movements in all these directions depending on the load, so that the damping is more effective with a larger load and less powerful with a lower load.

The invention is not limited to the embodiment shown in the figures, but the design of the components can be considerably changed. It is essential, however, that the movement of the bogie or wheel set or wheel support arm under the action of a loading force takes place in the opposite direction, as in direction B, in the figures, to the movement of the spring under the same loading force, i.e. direction C in the figures. In addition to this, the load force F or its sub-component P must act with unreduced power between these moving surfaces. Thus, for example, the embodiment of Figure 2 can be modified by moving the first and second friction surfaces to second distances and to second positions with respect to the axis lines 17a and 35 17b.

In addition, the actual suspension can be realized by another spring, e.g. a coil spring, as long as there is a member according to the invention between this spring and the first surface 18, which is compressed by the actual spring. Thus, for example, as a modification of the structure of Figure 2, the actual helical springs could apply their compressive forces P directly from the carriage body to the axle lines of the wheel bodies. In this case, the springs 9a, 9b are non-load-bearing auxiliary springs or resilient members, the ends 20a, 20b of which have friction surfaces 21a, 21b which press against the friction surfaces 18a, 18b of the bogie extension. The compressive force P is introduced, for example, directly between the friction surfaces 18a, 21a and 18b, 21b, respectively, by means of four helical springs located at the ends 20a, 10b.

Also, the compressive force P can be arranged to be directed towards the axis lines 17a, 17b in a direction other than 15 in the vertical direction PS, e.g. at an acute angle thereto. The friction surfaces 18 and 21 only need to be oriented respectively so that the normal of the surfaces forms approximately the same acute angle and in the same tilt direction as the vertical PS. In general, it is advantageous to make the surfaces 18 and 21 approximately 20 planar, whereby the movement of the parts of the wheel frames and the movement of the support frame relative to the wheel frames shown in connection with Fig. 1 is simply possible. It is conceivable for these surfaces, or either, to be shaped cylindrical or spherical or the like. However, it is advantageous to arrange the surfaces so that the compressive force P is directed on average perpendicular to them, whereby the surface does not cause additional tension or compression of the spring. However, it is conceivable that the friction surfaces 18, 21 are placed in an oblique, i.e. non-perpendicular, position with respect to the compressive force 30P, whereby the friction work is made desired in the different directions of movement of the vibration, i.e. the same or different. As described above, the design and placement of the springs also make the dampings in different directions desired in each case.

35 Only bogie structures have actually been described above. The support arm structure is conceivable as a modification of the articulated bogie when the second part of the wheel frame is omitted and the area of the coupling joint and the stabilizing structure is converted into an integral part of the frame.

10 82423

Thus, in the case of Fig. 2, if the joint 13, the stabilizing structure 16 and the support frame 6 were parts of or attached to the car body, the side part 14 would form a support arm which pivots about the joint 13 in resilience.

5

In the embodiment of the figures, the compressive force P is generated by springs directly from the load force F, but if necessary, a transferable articulation mechanism can be built in between, although in this case the structure becomes unnecessarily complicated.

10

Claims (11)

1. Damping structure for damping shocks or vibrations against the wheels or wheels of rail vehicles fitted with articulated bogie or wheel suspension with tow arms, by friction work generated between the vehicle body and its other structural part, depending on load force (F) and suspension play, characterized in that the first frictional surface (18a, 18b) of the damping structure is located on a fixed projection 10 (19a, 19b) of a part of the towing arm or bogie wheel body at a distance (S) from the axle line (17a, 17b) of the wheel or the wheel thread and the second friction surface (21a, 21b) have been formed between the end (20a, 20b) of the vehicle's spring or other resilient element (9a, 9b) and the first friction surface of the compressive force (P) arriving via the spring of the vehicle and depends on the load of the vehicle is at a substantial angle to the first and second surfaces, the frictional work rising between the first and second surfaces during the effect of the movement (B) transverse to the compressive force caused by the turning of the towing arm or wheel body and thus its projections (19a, 19b) caused by the pressing force (P) and the load. 2. A damping structure according to claim 1, characterized in that the first friction surface (18a, 18b) is a pitch or curved surface which is substantially perpendicular to the compressive force (P) of the vehicle's spring and the second friction surface (21a, 21b) lies in an elongate resilient element (9a, 9b) extending at least partially transversely to this pressing force, the end or ends facing away from the friction surface (21a, 21b) being coupled to the vehicle body or such (6). 35 A damping structure as claimed in claim 2, characterized in that the coupling point (23) of the elongated resilient element (9a, 9b) to the vehicle body or the like (6) and the articulation point (13) of the tractor arm is 82423 or the wheel body part of the vehicle body or the like is located on the same side of the vertical plane as is generally through the axis (17a, 17b) of the wheel or wheel thread and that the coupling point (23) of the elongated resilient element 5 lies either in the plane passing through the first surface (18a). , 18b) and is perpendicular to the compressive force (P) or at the distance (H) from this plane in a direction opposite to the direction of the compressive force (P). 10 A damping structure according to any of the preceding claims, characterized in that the pressing force (P) is arranged to align with the respective axle line (17a, 17b) of the wheel thread or wheel and that the first and second friction surfaces (18, 21) lie at a substantial angle. towards this direction. The damping structure according to claim 4, characterized in that the frictional surfaces (18, 21) are on average perpendicular to the compressive force (P). 20 The damping structure according to claim 4, characterized in that the frictional surfaces (18, 21) lie transversely at an angle to the compressive force (P), and the waveguide deviates from a straight line in the plane of the main suspension movement of the wheel body or the drag arm. A damping structure according to any preceding claim, characterized in that the pull arms or the lateral parts (14, 15) of the wheels are substantially horizontal and one friction surface (21) is on average substantially horizontal or forms an acute angle to the horizontal plane of the plane, whereby force strikes the friction surfaces substantially vertically or at an acute angle to the vertical line (PS). 35 A damping structure according to any of the preceding claims, characterized in that the coupling point (23) of said elongated resilient element (9) to the bogie's support frame (6) or the chassis of the vehicle or the like lies substantially on the height of the friction surfaces (18, 21) or above. . 5 An attenuating construction according to any preceding claim, characterized in that the elongated resilient member (9) is the vehicle's spring, such as a leaf spring, or a leaf of a package of leaf springs. 10. A damping structure according to any one of claims 1-8, characterized in that the elongated resilient member (9) is an elastic blade, disk or the like, which the actual vehicle spring presses against the first surface. 15 The damping structure according to any of claims 1-9, characterized in that the elongate member (6) and the second surfaces (21a, 21b) acting at the ends of the vehicle are pressed against the first 20 surfaces (18a, 18b) of the bogie's wheelbases. (2, 3) in the vertical plane that travels substantially through the axle lines of the wheels and that the frictional surfaces are on average horizontal and that the distance of the support body and the wheel body in line with the fastening joint is kept unchanged by means of a stabilizing structure (16).