|
(11) | EP 1 075 994 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
|
|
|
|
|||||||||||||||||||||||
| (54) | Drive unit for rail vehicle |
| (57) A drive unit (22) for propelling a rail vehicle (10) along a track includes a pair
of drive wheels (24) for engaging the track. The drive wheels (24) are mounted on
arms (26) which may be pivoted between a position in which the wheels (24) are in
driving engagement with the track and a position in which the wheels are out of driving
engagement with the track. The drive unit (22) may thus be used to selectively drive
the vehicle in a self propelled manner. The drive unit (22) may be folded out of the
way when the vehicle is to be propelled by a separate unit. |
[0001] The invention relates to a drive unit for a rail vehicle, and particularly to a drive unit for turning a conventional rail vehicle into a self propelled vehicle. The invention also relates to a rail vehicle provided with such a drive unit. The invention finds particular application in providing self propelled vehicles for use in the erection, renewal, repair and maintenance of railway lines, underground lines or tram lines.
[0002] Where the term "rail vehicle" is used throughout the specification, it is intended to refer to any vehicle which is able to run on railway lines, including underground lines and tram lines.
[0003] According to the invention there Is provided apparatus for propelling a rail vehicle along a track, the apparatus including rotary drive means for engaging the track and means for moving the drive means between a position in which they are in driving engagement with the track and a position in which they are out of driving engagement with the track.
[0004] Preferably the rotary drive means includes a pair of wheels, one for engaging each rail of the track. The rotary drive means may be mounted on one or more arms and the means for moving the rotary drive means may include means for pivoting the arms.
[0005] Preferably the or each arm includes resilient means for allowing small movements of the rotary drive means In a generally vertical direction in use. The resilient means may include one or more springs loaded by hydraulic cylinders.
[0006] Preferably the rotary drive means includes two drive wheels each mounted on an arm and, the drive wheels are connected by fixed length rods.
[0007] The means for moving the rotary drive means may include one or more hydraulic cylinders and hydraulic means for locking the drive means in either or their positions.
[0008] Preferably the apparatus includes means for transferring a proportion of the weight of the vehicle onto the rotary drive means. The means for transferring a proportion of the weight of the vehicle may include adjustable hydraulic cylinders.
[0009] Preferably the rotary drive means are driven by one or more hydraulic motor, co-axial with the rotary drive means.
[0011] The apparatus preferably includes means for removably mounting the apparatus on a rail vehicle.
[0012] According to the invention, there is also provided a rail vehicle provided with apparatus according to any of the preceding definitions. Preferably the apparatus is moveable to a position substantially above a base of the vehicle, such that the vehicle may be connected to a similar vehicle. The rail vehicle may be a universal container wagon provided with means for removably attaching containers or load platforms.
[0013] Embodiments of the invention will be described for the purpose of illustration only with reference to the accompanying drawings, in which:-
Fig. 1 is a diagrammatic side view of a two axle rail vehicle provided with a drive unit according to the invention;
Fig. 2 is a diagrammatic side view of a four axle rail vehicle provided with a drive unit according to the invention;
Fig. 3 is a diagrammatic side view of the drive unit of Figs. 1 and 2;
Fig. 4 is a diagrammatic front view of the drive unit of Fig. 3;
Fig. 5 is a diagrammatic plan view of the drive unit of Fig. 3; and
Fig. 6 is a diagrammatic partial side view of two rail vehicles in train formation, provided with drive units according to the invention, the drive units being in their raised positions.
[0014] Referring in particular to Figs. 1 and 2, a rail vehicle 10 includes a base 12 on which a removable platform 14 is mounted. The base 12 and the platform 14 are each provided with corner blocks which releasably engage with one another to clamp the platform 14 to the base 12. The vehicle 10 may be an ISO regulation raid wagon provided with a known "twist lock" system 15 for rapidly clamping structures/loads to the vehicle 10.
[0015] The base 12 is mounted on pairs of wheels 16. Fig. 1 shows a two axle vehicle having two pairs of rail, wheels 16a and 16b and Fig. 2 shows a four axle rail vehicle having four sets of rail wheels 16a and 16b.
[0016] The rail vehicle 10 is able to accommodate loads in containers or various working equipment 18 which may be fixed to the platform 14. The working equipment may include but is not limited to overhead line wiring equipment, for example, cable rewinding equipment for the removal and storage of old catenary and contact wire; tensioning equipment; cable drum carrier equipment and cable drums of new wire; hydraulic loader cranes; return conductor winch systems; or work platforms. The working equipment 18 may be mounted on the platform 14, and no modifications need be made to the vehicle 10 in order to accommodate the equipment 18.
[0017] The rail vehicle 10 is provided with a drive unit 22 which is able to propel the rail vehicle along a railway track 23, when the drive unit 22 is in the appropriate position, as described in more detail hereinafter. The drive unit 22 is releasably mounted on the platform 14 via twist locks 15. It is therefore not necessary to modify the vehicle 10 in order to accommodate the drive unit 22.
[0018] Referring in particular to Figs. 3 to 5, the drive unit 22 includes two drive wheels 24, one for engagement with each rail of the track 23. Each, drive wheel 24 is mounted on an arm 26, the two arms being joined by a cross brace 28. Each arm 26 incorporates a wheel support 30 provided with bearing springs 32, which allow the drive wheels 24 to adjust their position vertically. Oil pressure cylinders 34 load the bearing springs 32 in a controlled manner, to maintain the drive wheels 24 on the track 23 when they are in use. The pressure in the oil cylinders 34 is adjusted such that when the drive unit 22 propels the rail vehicle 10, the rail vehicle wheels 16a of the vehicle 10 are partially unloaded, a part of the weight of the vehicle being transferred to the drive wheels 24. The wheels 16a retain approximately 40% of their original load; this transfers sufficient load to the drive wheels 24 that they may drive the vehicle 10.
[0019] The drive wheels 24 are connected by pivotally mounted connecting rods 33, which ensure that the wheels 24 stay in gauge.
[0020] The drive wheels 24 are self propelled by means of hydraulic motors 36, fitted co-axially with the wheels 24. The motors 36 are powered from a hydraulic power unit 38 via flexible pipes 40. The hydraulic power unit 38 is mounted on the platform 14, as can be seen in. Figs. 1 and 2. The hydraulic power unit 38 is able to provided hydraulic fluid under pressure, and compressed air, and Is fitted with an endothermic engine, pumps, an oil tank, a fuel tank, compressed air, starting batteries and electric and emergency devices (not illustrated).
[0022] The rail vehicle wheels 16a, 16b are equipped with pneumatic brakes, controlled from the compressed air system which is powered by the hydraulic power unit and connected to the rail vehicle by a flexible pipe 42.
[0023] The drive unit 22 is mounted art the platform 12 via a large bearing 50, which allows the traction unit 22 to rotate about an axis indicated Y in the drawings. This allows the drive unit 22 to follow a curved railway track without de-railing.
[0024] The drive unit 22 may be pivoted or folded between the position shown in Figs. 1 to 5 and the position of Fig. 6. The arms 26 are mounted within bushes 29 and are able to rotate about an axis X to move the unit 22 between these two positions. The rotation of the arms 26 is controlled by oil pressure cylinders 32 which can be locked by hydraulic bolts 54 when the arms 26 are in their working positions.
[0025] The drive unit 22 may be controlled via a control panel 44 provided within a cabin 46. The movement and the braking of the drive wheels 26 may be controlled from this unit.
[0026] The drive unit 22 may be used in an overhead wiring operation as follows. Initially there is provided a train of rail vehicles 10 having drive units according to the invention. The vehicles may be fitted with various overhead line wiring equipment. The drive units 22 are all raised to the position shown in Fig. 6 and the vehicles are connected together and transported as a train in the normal way (at relatively high speed) to the track where the wiring operation is to be performed. Within the track possession, the rail vehicles are separated and the drive units 22 lowered to the positions shown in Figs. 1 to 5. The drive units 22 may then be used to propel the vehicles 10 at low, constant speeds within the possession, allowing the overhead line wiring work to be carried out.
[0027] The drive system 22 is suitable for a track with a gauge of 1,435mm (S) and also for greater (S3) or smaller (S2) gauge tracks (see Fig. 4). The drive unit 22 may be adjusted for different gauge tracks easily and quickly, by changing
[0028] There is thus provided an apparatus which allows a standard rail vehicle to be selectively self propelled when desired. The drive unit 22 may be fitted to essentially any two or more axled rail vehicle. The invention is particularly applicable to rail vehicles designed for ISO containers, such vehicles being fitted with means for attaching load platforms thereto. No modification of a standard ISO container wagon is necessary to allow the fitting of the drive unit 22. Because ISO container registered rail vehicles are available in most countries, apparatus according to the invention is extremely versatile.
[0029] When the drive unit 22 is not operating, the rail vehicle 10 transports a local equivalent to a container, and no further changes to the vehicle with regard to the pay load are required.
[0030] Various modifications may be made to the above without departing from the scope of the invention. It is not necessary that the drive wheels 24 are pivotally movable. Any means for moving them between a position in engagement with the track and a position out of engagement with the track may be used. The drive units 22 need nor be used with a standard container wagon, but may be fitted to essentially any rail vehicle.
[0031] Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed, to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.
1. Apparatus (22) for propelling a rail vehicle (10) along a track, the apparatus (22)
including rotary drive means (24) for engaging the track and means for moving the
drive means between a position in which they are in driving engagement with the track
and a position in which they are out of driving engagement with the track.
2. Apparatus (22) according to claim 1 wherein the rotary drive means includes a pair
of wheels (24), one for engaging each rail of the track.
3. Apparatus according to claim 1 or claim 2 wherein the rotary drive means (24) are
mounted on one or more arms (26) and the means for moving the rotary drive means (24)
includes means for pivoting the arms (26).
4. Apparatus according to claim 3 wherein the or each arm (26) includes resilient means
(32) for allowing small movements of the drive means in a generally vertical direction
in use.
5. Apparatus according to claim 4 wherein the resilient means includes one or more springs
(32) loaded by hydraulic cylinders (34).
6. Apparatus according to any of claims 3 to 5, wherein the rotary drive (24) means includes
two drive wheels each mounted on an arm (25) and the drive wheels (24) are connected
by fixed length rods (35).
7. Apparatus according to any preceding claim wherein the means for moving the rotary
drive means (24) includes one or more hydraulic cylinders (52) and hydraulic means
(54) for locking the drive means (24) in either of their positions.
8. Apparatus according to any preceding claim including means for transferring a proportion
of the weight of the vehicle onto the rotary drive means (24).
9. Apparatus according to claim 8 wherein the means for transferring a proportion of
the weight of the vehicle includes adjustable hydraulic cylinders (34).
10. Apparatus according to any preceding claim wherein the rotary drive means (24) are
driven by one or more hydraulic motor (36), co-axial with the rotary drive means.
11. Apparatus according to any preceding claim wherein the rotary drive means (24) are
provided with hydraulic braking means.
12. Apparatus according to any preceding claim, including means for removably mounting
the apparatus on a rail vehicle.
13. A rail vehicle (10) provided with apparatus (22) according to any preceding claim.
14. A rail vehicle (10) according to claim 13 wherein the apparatus (22) is moveable to
a position substantially above a base of the vehicle, such that the vehicle may be
connected to a similar vehicle.
15. Apparatus according to claim 13 or claim 14 wherein the rail vehicle (10) is a universal
container wagon provided with means (15) for removably attaching containers or load
platforms.
16. A drive unit (22) substantially as herein described with reference to the drawings.
17. A rail vehicle (10) provided with a drive unit (22) substantially as herein described
with reference to the drawings.
18. Any novel subject matter or combination including novel subject matter disclosed herein,
whether or not within the scope of or relating to the same invention as any of the
preceding claims.