WO2009021262A1

WO2009021262A1 - Two for one locomotive

Info

Publication number: WO2009021262A1
Application number: PCT/AU2007/001136
Authority: WO
Inventors: Brian Frederick Henderson
Original assignee: Brian Frederick Henderson
Priority date: 2007-08-14
Filing date: 2007-08-14
Publication date: 2009-02-19

Abstract

A ‘two for one locomotive’ configuration (40) is described having first and second articulated locomotive bodies (42) and (44), operatively coupled to each other via a semi-permanent flexible coupling (46) so as to effectively operate as a single locomotive. The first locomotive body (42) houses a diesel electric power assembly (48), and the second locomotive body (44) houses various ancillary locomotive components, including, for example, a fuel tank (14), battery box (16) and brake equipment (32) and (34). By relocating the weight of the ancillary locomotive components to a second locomotive body (44) a heavier, more powerful diesel electric power assembly (48) can be housed in the first locomotive body (42) than would normally be permissible due to the weight limitations of the railway track.

Description

"TWO FOR ONE LOCOMOTIVE" Field of the Invention

The present invention relates to an improved configuration for a railway locomotive and relates particularly, though not exclusively, to a locomotive configuration providing the tractive power of approximately two locomotives while the running costs are comparable to that of one locomotive.

Background to the Invention

Railway locomotives are built for different tasks and for various types of tracks. The axle load weight and rigid body length of the locomotive are restrictions that inhibit larger, more powerful locomotives from being operated on many railway systems. High horsepower is required for speed and tractive effort is required for pulling power. Many railways are forced to compromise with a multi-purpose locomotive that will haul a reasonable load at speed and yet still be able to haul a substantial load on a ruling grade. Accordingly such locomotives are unable to operate at maximum efficiency in either situation. Currently the usual way to increase horsepower or tractive effort on a train is to add additional locomotives and thus increase operating costs.

The present invention was developed with a view to providing a two for one locomotive to increase the available horsepower for speed over lightly graded track and to substantially increase the tractive effort when required for starting a train or confronting a ruling ascending grade.

References to prior art in this specification are provided for illustrative purposes only and are not to be taken as an admission that such prior art is part of the common general knowledge in Australia or elsewhere.

Summary of the Invention

According to one aspect of the present invention there is provided an improved configuration for a railway locomotive, the configuration comprising: first and second articulated locomotive bodies operatively coupled to each other so as to effectively operate as a single locomotive; the first locomotive body housing a diesel electric power assembly, and the second locomotive body housing various ancillary locomotive components, wherein the weight distributed over the first and second locomotive bodies is such that neither one of the locomotive bodies exceeds permissible weight limitations.

By relocating the weight of the ancillary locomotive components to a second locomotive body a heavier, more powerful diesel electric power assembly can be housed in the first locomotive body than would normally be permissible due to the weight limitations of the railway track. The invention is not limited to having two locomotive bodies or only one power assembly. The same concept can be implemented using three or more locomotive bodies and two or more power assemblies to achieve improved weight distribution and an increase in the available horsepower for speed.

Advantageously the first and second locomotive bodies may be of reduced length compared to a conventional locomotive body so as to allow for operation on tighter curved track. Preferably a driver's cab is provided at each end of the articulated locomotive bodies so as to permit the locomotive to be operated in either direction.

Typically said power assembly comprises a larger internal combustion engine, and an alternator/generator driven by the diesel engine. A plurality of electric traction motors are supplied with electrical energy from the alternator/generator, and wherein the number of traction motors supplied with electrical energy can be varied depending on the load requirements placed on the locomotive.

Preferably when maximum tractive effort is required to start a heavy train or ascend a ruling grade the power assembly supplies electrical energy to all the traction motors. Preferably as the speed is increased, and the requirement for tractive effort is reduced, and more horsepower is required, the electrical energy is supplied to a proportionally reduced number of the traction motors. Further increase in speed may result in the electrical energy being fed to a further reduced number of traction motors. Alternatively, depending on the type of technology being used, all the traction motors may be energised continuously while under load.

Throughout the specification, unless the context requires otherwise, the word "comprise" or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers. Likewise the word "preferably" or variations such as "preferred", will be understood to imply that a stated integer or group of integers is desirable but not essential to the working of the invention.

Brief Description of the Drawings The nature of the invention will be better understood from the following detailed description of preferred embodiments of an improved locomotive configuration, given by way of example only, with reference to the accompanying drawings, in which:

Figure 1 shows the configuration of a typical prior art multi-purpose diesel electric locomotive; and,

Figure 2 shows a preferred embodiment of a two for one locomotive configuration in accordance with the present invention.

Detailed Description of Preferred Embodiments

A typical multi-purpose diesel electric locomotive currently operating in Western Australia is the General Electric 2500 HP-1830 KW "P" class locomotive 10 illustrated in Figure 1. The "P" class can operate all over the railway system as it is within the 16-17 tonne axle load limit required on many of the branch lines in the state. Many of the trains operating in WA are required to use more than one locomotive to supply the required power. To permit the "P" class to operate effectively on a 17 tonne axle load, its power output has been de-rated. If the permissible axle loading was increased the locomotive could be rated to its maximum efficiency of 3000 HP-2240 KW. The cost of improving the efficiency is that it would severely restrict the area of operation to the railway tracks with heavy rail. As shown in Figure 1 , the "P" class layout, which is typical of WA locomotives, has a single driving cabin 12 at one end with dual driving control stands for bidirectional operation. It has six axles with an electric traction motor (not visible) driving each axle in a Co-Co bogie configuration. There are two bogies with three traction motors each, and hence six traction motors altogether on the locomotive. A fuel tank 14, battery box 16 and air reservoirs 18 are mounted below the chassis between the two bogie wheel sets. Above the chassis is the power assembly, comprising a diesel engine 20 and main alternator 22, together with an expansion tank 24 for engine coolant, a radiator 26 and cooling fan 28. The diesel engine is typically a twelve cylinder 1830 KW traction internal combustion engine.

Within the engine room area there is also a compressor 30, dynamic brake equipment 32, traction motor blower (not shown), equipment blower (not shown) and other ancillary components. There are also lockers and cabinets on the locomotive 10 housing air brake equipment 34, electrical equipment 36, a tool box, train operating equipment and spare parts, etc. A toilet and hand basin with a domestic water supply is also provided for crew hygiene in a toilet and wash area 38. All of these ancillary components and equipment add substantially to the overall weight of the locomotive 10, further limiting the size of the engine that can be employed in the power assembly. A preferred embodiment of a 'two for one locomotive' configuration 40 in accordance with the invention, as illustrated in Figure 2, comprises first and second articulated locomotive bodies 42 and 44, operatively coupled to each other via a semi-permanent flexible coupling 46 so as to effectively operate as a single locomotive. The first locomotive body 42 houses a diesel electric power assembly 48, and the second locomotive body 44 houses various ancillary locomotive components, including, for example, a fuel tank 14, battery box 16 and brake equipment 32 and 34. To ensure the first locomotive body 42 does not exceed the 16-17 tonne axle load restriction, any components and equipment that can be transferred to the second locomotive body 44 are housed in the second locomotive body 44. In Figure 2 the similar parts of the locomotive 40 have been identified with the same reference numerals as in Figure 1 , and will not be described again in detail. The ancillary components transferred to the second locomotive body 44 include, but are not restricted to, fuel tank 14, battery box 16, air reservoirs 18, compressor 30, dynamic brake equipment 32 and air brake equipment 34. Any other equipment and components that can be effectively connected by cable or flexible pipe could be included until the required weight transfer is achieved. Items such as toilet and wash area 38 and all tools, train equipment, and spare parts, etc can also be housed in the second locomotive body 44. The weight is thus distributed over the first and second locomotive bodies 42 and 44 such that neither one of the locomotive bodies exceeds permissible weight limitations.

By relocating the weight of the ancillary locomotive components to a second locomotive body 44 a heavier, more powerful diesel electric power assembly 48 can be housed in the first locomotive body than would normally be permissible due to the weight limitations of the railway track. The economic benefit to the operator is that for approximately the cost of building 1.5 locomotives the 'two for one locomotive' will haul the load of approximately two locomotives while the running costs should be only marginally higher than a single locomotive. The invention is not limited to having two locomotive bodies or only one power assembly or a Co-Co bogie arrangement as shown. Some railway systems may require more traction motors on more articulated bodies to suit their system. The same concept can be implemented using more than two locomotive bodies and/or more than one power assembly to achieve improved weight distribution and an increase in the available horsepower.

Advantageously the first and second locomotive bodies 42 and 44 may be of reduced length compared to a conventional locomotive body so as to allow for operation on tighter curved track. Preferably two driver's cabs 12a and 12b are provided at each end of the 'two for one locomotive' 40. A single control stand is provided in each cabin 12 respectively, so as to permit the locomotive 40 to be operated in either direction.

Typically the power assembly comprises a larger diesel-fuelled internal combustion engine, and an alternator driven by the diesel engine. For example, a 16 cylinder diesel engine capable of producing between 3350 KW and 4475 KW could be employed. A plurality of electric traction motors (not visible) are supplied with electrical energy from the alternator, and wherein the number of traction motors supplied with electrical energy can be varied depending on the load requirements placed on the locomotive.

The principal object of the 'two for one locomotive' configuration may be summed up as allowing a railway system with axle load limitations, and physical size and length limitations due to tight curves or tunnels etc, to operate high powered locomotives that until now have only been available to heavy haul railway systems. For example, a 6000 HP - 4480 KW locomotive operating on a heavy gauge railway, such as the iron ore trains in the north of Western Australia, have axle loads of approximately 35 tonnes. The 'two for one locomotive' will allow such a 6000 HP - 4480 KW locomotive to operate on most of the standard gauge railway systems in Australia where locomotives are limited to approximately a 23 tonne axle load. It should be noted that the 'two for one locomotive' of the invention is suitable for use with either AC or DC traction equipment. Hence it will be apparent that either an alternator or a generator would be employed in the power assembly to supply electric power to the traction equipment. Likewise, it will be understood that the expression "diesel electric" is intended to encompass power assemblies that employ an internal combustion engine using alternative fuels such as LPG, LNG, Bio-fuels, etc, and is not limited to power assemblies operating on conventional diesel fuel. Now that a preferred embodiment of the improved locomotive configuration has been described in detail, it will be apparent that the embodiment provides a number of advantages over the prior art, including the following:

(i) It is capable of working unrestricted over the whole rail system.

(ii) It substantially eliminates or reduces the need for having multiple locomotives on many trains. For example, two "P" class locomotives on a train will produce approximately 3700 KW using two internal combustion engines. One 'two for one locomotive' will produce approximately 3800 KW using only one engine.

(iii) It is capable of efficiently hauling trains that are currently being worked by heavy axle load locomotives on heavy rail tracks.

(iv) The fuel and running costs will be substantially reduced when a single engine locomotive replaces two locomotives and supplies the same or more power.

(v) Because it is running one internal combustion engine only it will still be economical when hauling a train that otherwise may not need such a powerful locomotive.

(vi) It substantially eliminates or reduces the need to have locomotives that can only work in restricted areas, thereby increasing the efficiency of the railway, particularly when a locomotive may be required in a light axle load area at short notice. (vii) It will be more environmentally friendly, helping to reduce the volume of greenhouse gases being exhausted into the atmosphere, as the number of internal combustion engines being used in the rail industry will be reduced.

It will be readily apparent to persons skilled in the relevant arts that various modifications and improvements may be made to the foregoing embodiments, in addition to those already described, without departing from the basic inventive concepts of the present invention. For example, the size and length of the first and second locomotive bodies and any additional locomotive bodies need not be the same. Therefore, it will be appreciated that the scope of the invention is not limited to the specific embodiments described and is to be determined from the appended claims.

Claims

The Claims defining the Invention are as follows: 1. An improved configuration for a railway locomotive, the configuration comprising: first and second articulated locomotive bodies operatively coupled to each other so as to effectively operate as a single locomotive; the first locomotive body housing a diesel electric power assembly, and the second locomotive body housing various ancillary locomotive components, wherein the size of the power assembly is maximised and the weight distributed over the first and second locomotive bodies is such that neither one of the locomotive bodies exceeds permissible weight limitations.

2. An improved configuration for a railway locomotive as defined in claim 1 , wherein the ancillary locomotive components housed in the second locomotive body include a fuel tank, battery box, air reservoirs, compressor, dynamic brake equipment and air brake equipment.

3. An improved configuration for a railway locomotive as defined in claim 1 or claim 2, wherein items such as a toilet and wash area and all tools, train equipment, and spare parts, etc are also housed in the second locomotive body.

4. An improved configuration for a railway locomotive as defined in any one of claims 1 , 2 or 3, wherein any other equipment and components that can be effectively connected by cable or flexible pipe are housed in the second locomotive body until the required weight transfer is achieved.

5. An improved configuration for a railway locomotive as defined in any one of the preceding claims, wherein the first and second articulated locomotive bodies are operatively coupled to each other via a semi-permanent flexible coupling.

6. An improved configuration for a railway locomotive as defined in any one of the preceding claims, wherein the first and second locomotive bodies are of reduced length compared to a conventional locomotive body so as to allow for operation on tighter curved track.

7. An improved configuration for a railway locomotive as defined in any one of the preceding claims, wherein more than two locomotive bodies and/or more than one power assembly are employed to achieve improved weight distribution and an increase in the available horsepower.

8. An improved configuration for a railway locomotive as defined in any one of the preceding claims, wherein a driver's cab is provided at each end of the articulated locomotive bodies so as to permit the locomotive to be operated in either direction.

9. An improved configuration for a railway locomotive as defined in any one of the preceding claims, wherein said power assembly comprises a more powerful internal combustion engine than would normally be permissible due to the weight limitations of the railway track, and an alternator/generator driven by the internal combustion engine.

10. An improved configuration for a railway locomotive as defined in any one of the preceding claims, wherein a plurality of electric traction motors are supplied with electrical energy from the alternator/generator, and wherein the number of traction motors supplied with electrical energy can be varied depending on the load requirements placed on the locomotive.

11. An improved configuration for a railway locomotive as defined in claim 10, wherein when maximum tractive effort is required to start a heavy train or ascend a ruling grade the power assembly supplies electrical energy to all the traction motors.

12. An improved configuration for a railway locomotive as defined in claim 10 or claim 11 , wherein as the speed is increased, and the requirement for tractive effort is reduced, and more horsepower is required, the electrical energy is supplied to a proportionally reduced number of the traction motors.

13. An improved configuration for a railway locomotive as defined in claim 12, wherein a further increase in speed results in the electrical energy being fed to a further reduced number of traction motors.

14. An improved configuration for a railway locomotive as defined in claim 10, wherein all the traction motors are energised continuously while under load.

15. An improved configuration for a railway locomotive substantially as herein described with reference to and as illustrated in Figure 2 of the accompanying drawings.