DE102012024857A1 - Method for accelerating and moving train covered by locomotive, involves lowering drive wheel on rails for start-up process at batch wagon operating in train, where batch wagon is pressed with certain pressure force on rails - Google Patents

Abstract

The method involves lowering a drive wheel on the rails for the start-up process at a batch wagon (2) operating in a train (1). The batch wagon is pressed with a certain pressure force on the rails. The traction-or pressure force is carried on the train in a locomotive (5) and in the batch wagon. The drive wheel of the batch wagon is lifted from the rails in a coordinated way after reaching a predetermined speed of the train. An independent claim is included for a batch wagon with an electric contact wire.

Description

The present invention relates to a method and thereby usable devices for acceleration and movement of trains.

On long and heavy trains - especially freight trains - it comes again and again to start problems on inclines or in bad weather (fog, rain, snow, ice). In these cases, the maximum possible starting tractive force of the locomotive in the respective situation is no longer sufficient to overcome the resistance forces of the train and it is therefore impossible to start the train association.

The maximum possible starting tractive effort of a locomotive is less limited by the technical possibilities (power of the engines, etc.) than by the friction conditions on the drive wheels. In this case, in addition to the normal force ("weight") in particular the coefficient of friction plays a crucial role. The corresponding formula is "friction force = weight force (= mass × gravitational acceleration) × friction coefficient".

Since the normal force is limited by the maximum permissible axle load (approximately 21.5 t), the maximum possible tractive force of the locomotive is thus decisively influenced by the friction conditions in the form of the coefficient of friction between the wheel and the rail. For this coefficient of friction, a value of 0.3 to 0.4 can be assumed for dry rail, while it is often below 0.15 for wet, greasy rail (rain, fog, snow, ice, leaves).

The abovementioned maximum values are significantly higher than the values normally given in the literature for the steel / steel pairing. This is due to the fact that modern control technology makes optimum use of the slip on each drive wheel of a locomotive (or on each drive axle), which results in very high tractive forces.

Modern, four-axle electric locomotives reach at self-weights of about 86 t Anfahrzugkräfte of about 300 kN (eg, series 101, BR 152). In bad weather conditions, this value drops to below 100 kN. Through the use of heavier, six- or eight-axle locomotives, this value could indeed be increased approximately linearly with the dead weight, but such locomotives are z. B. in the Deutsche Bahn no longer procured (or only in exceptional cases), since the large total mass claimed the substructure (rails, sleepers, etc.) disproportionately.

At Deutsche Bahn, the load limits for 4-axle locomotives today are generally apparent at 3,000 t draw weight in the plane and 2,700 t on routes with a maximum of 6 promille slope. In order to move a 3,000 t train, about 200 kN tensile force is required. It can be seen that these forces can only be applied by a 4-axle single locomotive if the rail conditions are reasonably good. Aggravating for the starting process (in addition to the weather conditions) are often added slope sections in which the train had to stop, or areas in which the tracks are in curves (which also increases the resistance of the train).

If the coefficient of friction falls below a critical limit, the wheels of the locomotive start to spin as the driving torques increase further, which can result in extreme damage to the substructure and very high wear on the locomotive. Spinning drive wheels are sometimes referred to as "spin". In these cases, there are initially two common measures for train drivers to be able to set the train in motion.

In the first approach, the train is compressed backwards with the locomotive before the actual departure. This is possible because of the connections between the wagons (couplings) always a certain "lots" exists, d. H. the wagons are never coupled together in a massive unit. If the locomotive is moving forward again, one wagon after the other is transferred from the state of static friction to that of the rolling friction (rolling friction ≈ 50% of the static friction).

However, this procedure works only conditionally in a pitch piece, since after releasing the brake, the wagons can roll back here or would be set backwards by the backward pushing locomotive in motion and thus the situation would only be worsened.

The second approach is the so-called "sanding". It is sprinkled by small pipes in front of the wheels of the locomotive sand on the rails. This significantly improves the coefficient of friction between wheel and rail so that better starting tractive forces can be achieved even in wet weather. A disadvantage of this procedure, however, is the high wear that occurs on wheels and rails. Similarly, the supply of sand is limited, so that situations can occur, where trains are left for lack of sand.

If the two described measures can not be applied or are not sufficient, there is often no other option but to request an additional train or train Schublokomotive to overcome the critical area. It is obvious that the resulting waiting times - especially on single-track sections - massive disruption of the timetable arise. In addition to the inconvenience to the passengers of affected passenger trains and the economic consequences for the railway are sometimes significant.

The problem described will be exacerbated in the future, since on the one hand the still existing in the vehicle population of the DB 6-axis locomotives are gradually phased out (eg BR 151 and BR 155) and on the other hand, both the train length and the train weights increased should be. The maximum train length is to be doubled from 750 m to 1,500 m and the maximum train mass even tripled from 3,000 t to approx. 9,000 t (ore trains).

From today's point of view, this task can only be solved by means of complex double or triple tractions (ie several locomotives per train unit). For economic reasons, however, it can be assumed that the future tensile masses will also run with a technically just permissible "minimum covering", ie. H. Also for the new, overweight trains similar problems will occur as for today's standard trains, namely insufficient traction in borderline situations, especially when starting.

A safety-relevant aspect of insufficient traction results in addition to special danger routes such. Eg tunnels. For safety reasons, two locomotives are sometimes used here even on relatively light trains, in order to be able to safely move the train out of the tunnel in the event of a locomotive failure.

The present invention has for its object to provide a method and thereby deployable devices, with the help of which it is also economically possible to put trains back in motion, the alone of the strained locomotive for reasons of insufficient friction coefficient between drive wheels of the locomotive and the rails not can be approached more.

The technical problem is solved by a method according to the features of claims 1 to 5 and thereby usable devices according to the features of claims 6 to 10.

By a novel (hereinafter referred to as "pushcar") type of vehicle, are designed in the wagons as auxiliary locomotives, the forces acting on a train tensile or compressive forces can be increased so that even under difficult conditions safe starting and moving is possible.

During "normal" driving - d. H. with sufficient traction of the strained locomotive - run the wagons quasi as "normal" wagons in train operation. If it then comes to one of the emergency situations described above, then the drive car - mounted between the normal wheels - special drive wheels lowered onto the rails and pressed with a certain pressure on the rails.

The lowering of the drive wheels can be done either manually by the engine driver or even in an automatic mode in which z. B. at each stop of the train, the drive wheels are automatically lowered and support the acceleration process when starting. After reaching a predetermined speed (eg 40 km / h), the drive wheels can then be automatically moved up again.

The monitoring of a smooth functioning of the push-car can be controlled during operation by a camera surveillance. For this purpose, the monitor can be accommodated in the cab of the locomotive.

The normal wheels act as a guide device for the drive wheels, d. H. they prevent the drive wheels of the pushcart from running off the rails. By a corresponding structural design (eg steering or lateral Verschubungsmöglichkeit) also a Kurvengängigkeit the drive wheels can be achieved, so that they can optimally follow the track. The steering angle can be accurately determined and controlled by sensors on the vehicle.

The required pressure force of the drive wheels is taken from the weight of the pushcar. At a weight of the pushcar of z. B. 60 t results in a four-axle chassis axle load of 15 t. If the drive wheels now z. B. charged with 40 t, so reduces the axle load of the wheels accordingly to 5 t. The value of the load of running and driving wheels is adjusted so that on the one hand an optimal guidance of the pushcart on the rails is ensured and on the other hand a maximum traction force of the drive wheels is achieved. This is usually done by minimizing the load on the wheels and maximizing the load on the drive wheels.

As part of a further optimization, it is also possible to pull up individual wheels or axles with wheels, so that they no longer have any contact with the rails. As a result, the drive wheels further pressure force available without having to increase the overall weight of the pushcart. In the end, the possible thrust or tractive force of the push-car will be increased.

The drive wheels are preferably to be provided with a surface which is characterized by particularly high coefficients of friction between the surface and the steel of the rails. In a material pairing of z. As rubber with steel values between 0.7 (favorable conditions) and 0.4 (unfavorable conditions) are readily possible.

In the case of the above-exemplified load of 40 t drive wheels, even with a friction coefficient of 0.5, approximately 200 kN thrust or tractive force result.

The drive of the drive wheels of the pushcart can be done both diesel-electric-hydraulic and diesel-mechanical, electro-mechanical or electro-hydraulic. When using electricity as the primary energy, the supply of the drive unit z. B. over the normal contact wire ("overhead line") or via batteries. The batteries or accumulators can be charged during normal driving by generators that are driven by the wheels.

For the start of an awkward situation, the forces of the locomotive are combined with those of the pushcart, which in some cases may well lead to more than a doubling of the forces acting on the train.

Once the train has reached a certain speed (eg 40 km / h), the drive wheels of the pushcar are retracted again and the locomotive then moves the train again only with the means at its disposal. The boxcar then runs as a normal wagon in the train and can thereby with high drive wheels - depending on the technical design - easily and safely reach the high speeds of conventional freight cars (about 80 to 160 km / h).

Basically, the pushcar can be placed at all positions in the train, d. H. either directly behind the locomotive, at the end of the train or at any position in between. It is also possible to integrate several push cars in a train.

Should a train in which a box truck is already running remain in a critical area due to the complete failure of the locomotive (eg in a tunnel), then under most conditions a pushcar would be able to pull the entire train in slow driving alone (ie without the assistance of a locomotive) to push out of the danger area.

An additional use for pushcars is conceivable in shunting. By designing the pushcar with two driver's stands (or even only by remote control), it is possible to use the vehicle as an independent shunting locomotive. The conceivable shear forces at a dead weight of z. B. 60 t are in the range of 160-280 kN and are comparable or even higher than the corresponding values of today's shunting locomotives (eg BR 347 with 60 t weight and a maximum Anfahrzugkraft - under favorable friction conditions - less than 200) kN).

It is also possible, by appropriate design of the drive axles (lowering depth, steerability) to push the boxcar "out of the rails" and drive short distances on the road. The drive wheels are lowered so far (eg by means of hydraulic cylinders) that the normal wheels no longer have ground contact. The steerability of the push car on the road can then be done either by means of steering axles or unilateral control of the drive wheels (system tracked vehicle).

This makes it possible to quickly move the pushcar from one track to another or to quickly clear a particular track. Likewise, a pushcar can then be parked in a convenient location, without blocking tracks.

Instead of driving wheels, it is possible to mount rubber tracks existing drives on the boxcar. Such drives can be found today on large farm tractors and combine harvesters. Due to the large contact surface and a corresponding structuring of the rubber track, particularly high traction performance can be achieved. The integration of electromagnets in the tracks (as proposed, for example, in Patent Specification No. 418274 / Class 20b / Group 15), the achievable feed forces can be further increased.

In addition to the acceleration of trains, a pushcar can also be used for braking trains by the drive wheels in the upper position (ie without contact with the rails) are first brought to a speed, the corresponds to the current speed of the train, then the drive wheels are lowered onto the rails and loaded with a predetermined vertical force and then the drive wheels are selectively braked.

Depending on the implementation of the drive module (engine, power transmission, movement mechanism, steering device, etc.), the pushcars may also have areas that are designed for receiving cargo.

Two-way shunting vehicles are known from today's railway practice. However, these are primarily road vehicles, on the frame of spur wheels can be lowered, which then lead the vehicle safely on the rails. A well-known vehicle for this application is the Unimog, which is often retrofitted in the form described and then with a dead weight of about 12 t draw weights can move safely up to 1,000 t. However, for technical reasons, these two-way shunting vehicles are only designed for very low speeds on the rail (with load approx. 20 km / h, without load approx. 40 km / h)

• 1. „Normaler” Zugbetrieb bzw. Reisezustand = Laufräder auf den Schienen, Antriebsräder in der Luft
• 2. Schub- bzw. Druckbetrieb bzw. Rangierbetrieb = Laufräder auf den Schienen, Antriebsräder auf den Schienen
• 3. Sonderbetrieb bzw. Straßenbetrieb = Laufräder in der Luft, Antriebsräder auf der Straße

The method according to the invention and the devices which can be used in this case differ from the prior art in particular in that three (instead of the previous two) operating states are provided, namely:

• 1. "Normal" train operation or travel state = wheels on the rails, drive wheels in the air
• 2. pushing or printing operation or maneuvering = wheels on the rails, drive wheels on the rails
• 3. Special operation or road operation = wheels in the air, drive wheels on the road

Another distinguishing criterion over the prior art is the high speed of movement that can be achieved with the pushcar. Since this vehicle is based on the concept of conventional freight cars, comparatively high speeds can be achieved in the travel mode as with normal wagons, d. H. about 80 to 160 km / h.

The advantages of the method according to the invention and of the devices which can be used in this case are in particular in the economic sector, since a push-car only requires a fraction (approximately 10-20%) of the investment and maintenance costs of a modern locomotive.

The possibility of multiple use (eg in shunting operations) also considerably increases the flexibility of the railway operator. Likewise safety aspects are to be mentioned, since it is relatively easy to integrate a push car in a train, which must drive a critical distance. The provision of an additional locomotive is the other hand, more difficult, especially if the number of usable locomotives by the scheduled utilization is already very high.

The method according to the invention and devices which can be used in the process are illustrated with reference to drawings and explained below, wherein the features shown there have exemplary character. The drawings show:

1 : Exemplary representation of possible positioning of a push-car in a train.

2 : Exemplary representation of a simple pushcart in three different operating states.

3 : Exemplary representation of a push-car in design as a shunting locomotive with drive wheels in three different operating states.

4 : Exemplary representation of a push wagon in configuration as a shunting locomotive with chain drive in three different operating states.

In 1 is exemplified, at which positions within a train 1 a push-cart 2 can be placed. In 1a is the boxcar 2 at the end of the turn 1 and transmits in the example shear forces on the train 1 , In 1b is the boxcar 2 in the middle of the turn 1 and there can be both pushing forces on the between the pushcar 2 and locomotive 5 located part of the train 1 transferred as well as tensile forces on the behind the boxcar 2 located part of the train 1 , In 1c is the boxcar 2 directly behind the locomotive 5 arranged and can in this position shear forces on the locomotive 5 and / or pulling forces on the train 1 muster.

In 2 exemplifies a relatively simple embodiment of a pushcovers 2 shown. There is a drive module 7 with the drive wheels 3 within a leadership 10 and can be within the leadership 10 by means of hydraulic cylinders 9 be moved vertically. 2a shows the state with raised drive wheels 3 , ie in this state have only the wheels 8th Contact with the rails 4 and thereby lead the pushcar 2 safe on the rails. This setting is preferred when the pushcar 2 at high speed within a turn 1 starts to rotate.

In 2 B is the "working mode" of the pushcart 2 shown. This is the drive module 7 from the hydraulic cylinders 9 within the leadership 10 with a predetermined force on the rails 4 pressed. This relieves the wheels 8th , but only as far as that still a safe guidance of the Schubwaggons 2 on the rails 4 is guaranteed. In this operating condition can from the boxcar 2 over the drive wheels 3 Forces on the rails 4 be transferred so that the boxcar 2 in any direction on the rails 4 can be moved while even push or pull forces on vehicles connected to him (not shown) can transmit.

In 2c is a "special mode" shown in which a pushcar 2 on a fixed surface such. B. a street 11 emotional. This is possible by the drive module 7 within the leadership 10 from the hydraulic cylinders 9 moved so far down that the wheels 8th have no ground contact. Through the use of steerable drive wheels 3 or separately controllable drive wheels 3 one side of the drive module 7 is it possible to use the pushcart 2 - at least over short distances - to move controlled on its own power on fixed surfaces.

In 3 becomes a more elaborate design of a push-car 2 shown. Here are on the boxcar 2 exemplary two control stations 13 arranged, from which the Schubwaggon 2 can be used by appropriately trained personnel as shunting locomotive. Regardless, the pushcar in a preferred embodiment may also be remotely controlled. To transmit corresponding signals and data are on the boxcar antennas 14 ,

3a shows the state in which the boxcar 2 is in "travel mode", ie the wheels 8th have contact with the rails 4 and lead the boxcar 2 safe on the rails 4 , The drive module 7 has started up, leaving the drive wheels 3 no contact with the rails 4 exhibit. As in this state, no drive energy for the drive module 7 is needed is the pantograph 12 , the electrical energy from the contact wire 6 can not be activated. This setting is preferred when the pushcar 2 at high speed within a turn 1 starts to rotate.

In 3b is the "working mode" of the pushcart 2 shown. This is the drive module 7 from the hydraulic cylinders 9 within the leadership 10 with a predetermined force on the rails 4 pressed. This relieves the wheels 8th , but only as far as that still a safe guidance of the Schubwaggons 2 on the rails 4 is guaranteed. In a preferred embodiment, the drive module is via a control and energy chain 15 with the superstructure of the pushcart 2 connected. In this operating condition can from the boxcar 2 over the drive wheels 3 Forces on the rails 4 be transferred so that the boxcar 2 in any direction on the rails 4 can be moved while pushing or pulling forces on it connected vehicles of the train 1 can transfer. The required primary energy for the drive wheels is via at least one pantograph 12 a contact wire 6 over the rails 4 taken.

In 3c Again, a "special mode" is shown in which a pushcar 2 on a fixed surface such. B. a street 11 emotional. This is possible by the drive module 7 within the leadership 10 from the hydraulic cylinders 9 moved so far down that the wheels 8th have no ground contact. Through the use of steerable drive wheels 3 or separately controllable drive wheels 3 one side of the drive module 7 is it possible to use the pushcart 2 - at least over short distances - controlled to move under its own power.

In 4 (a, b and c) is in principle the same facts as in the 3a to 3c shown, with the difference that in place of drive wheels 3 now a drive chain 16 is provided for generating the tensile and compressive force. Depending on the structural design, such an embodiment can achieve advantages in terms of the achievable traction and / or wear values compared with drive wheels.

LIST OF REFERENCE NUMBERS

1

train

2

push car

3

drive wheel

4

rails

5

locomotive

6

contact wire

7

drive module

8th

Wheel

9

hydraulic cylinders

10

guide

11

Street

12

pantograph

13

helm

14

antenna

15

Control and energy chain

16

drive chain

Claims (10)

Method for accelerating and moving by at least one locomotive covered Trains, characterized in that for the starting process at least one in a train ( 1 ) located Schubwagen ( 2 ) at least one drive wheel ( 3 ) on tracks ( 4 ) lowered and with a certain pressure on the rails ( 4 ) and then in a concerted manner both a locomotive ( 5 ) as well as the Schubwaggon ( 2 ) Tensile or compressive forces on the train ( 1 ) and train ( 1 ) after reaching a predetermined speed of the train ( 1 ) the at least one drive wheel ( 3 ) of the push-cart ( 2 ) from the rails ( 4 ) and the locomotive ( 5 ) the Train ( 1 ) is further accelerated and moved to the respective intended final speed. Method according to Claim 1, characterized in that the activation, operation and deactivation of the at least one drive wheel ( 3 ) of the push-cart ( 2 ) are executed automatically. Method according to claim 1 and 2, characterized in that the activation, the operation and the deactivation of the at least one drive wheel ( 3 ) of the push-cart ( 2 ) are monitored by camera. Method according to one or more of the preceding claims, characterized in that a train ( 1 ) with or without locomotive ( 5 ) from a standstill up to a speed of about 40 km / h from the push-cart alone ( 2 ) is accelerated and moved. Method according to one or more of the preceding claims, characterized in that the at least one drive wheel ( 3 ) in off-hook condition to a speed corresponding to the current speed of the train ( 1 ) is accelerated, the at least one drive wheel ( 3 ) on the rails ( 4 ) lowered and with a certain pressure on the rails ( 4 ) and then the at least one drive wheel ( 3 ) is decelerated with a certain delay value. Schubwagon ( 2 ) according to one or more of the preceding claims, characterized in that the primary energy for driving the at least one drive wheel ( 3 ) an electrical contact wire ( 6 ) over the rails ( 4 ) is taken. Schubwagon ( 2 ) according to one or more of the preceding claims, characterized in that the primary energy for driving the at least one drive wheel ( 3 ) of at least one in the push-cart ( 2 ) and the battery is removed during the movement of the train ( 1 ) is charged. Schubwagon ( 2 ) according to one or more of the preceding claims, characterized in that the primary energy for driving the at least one drive wheel ( 3 ) of at least one in the push-cart ( 2 ) is generated internal combustion engine. Schubwagon ( 2 ) according to one or more of the preceding claims, characterized in that the push-cart ( 2 ) with deactivated, at least one drive wheel ( 3 ) is designed for maximum speeds of at least 80 km / h. Schubwagon ( 2 ) according to one or more of the preceding claims that the pushcar ( 2 ) Has devices for receiving charge.

Images