GB2165582A

GB2165582A - Power generation arrangement

Info

Publication number: GB2165582A
Application number: GB08520909A
Authority: GB
Inventors: Eric Sidebotham
Original assignee: GEC General Signal Ltd
Current assignee: GEC General Signal Ltd
Priority date: 1984-10-10
Filing date: 1985-08-21
Publication date: 1986-04-16
Also published as: GB8425641D0; GB8520909D0

Abstract

A device for powering a level crossing or other path selection or controlling means at remote locations where it is impractical to provide an electric main, and expensive to provide a local electricity source. The invention provides a hydraulic accumulator (6) energised by a pump (7) which is worked by the wheels of a train pressing a lever set into the rail (1a). The wheels may depress a ball bearing in the rail to press the lever. Alternatively, the wheels may compress a resilient, fluid-containing, pumping tube. The energy stored can be used to operate level crossing barriers (4), lights or points. The system could be used on other vehicle paths. <IMAGE>

Description

SPECIFICATION Power generation arrangement The present invention relates to power generation particularly, but not exclusively for use on railway lines at remote locations.

Appreciable amounts of power are intermittently required at level crossings, in order to raise the level crossing barriers. In cases where the level crossing is in an isolated location it is often impractical to provide an electric main, particularly when the railway line passes through a jungle or a desert, for example. Accordingly, it has been proposed to provide a local electricity source such as a wind storage battery, to power the level crossing gates and additionally to power the required electric signals, indicators etc. However such arrangements are expensive.

Similar problems can arise at railway points located at isolated railway junctions.

According to one aspect of the present invention an arrangement comprising at least two intersection vehicle paths, and path-selection means for selectively permitting and denying access to said vehicle paths, further comprises actuating means located near the intersection of said paths and drivingly coupled to said path-selection means, said actuating means being arranged in use to be energised by a vehicle moving in a first one of said paths and to provide power to enable said path-selection means to permit or deny access to at least one of said paths.

The actuating means may be arranged to trigger the path selection means in response to the passage of said vehicle, so as to open or block one of said paths. Alternatively the path selection means may be triggered manually or in response to an electrical signal, for example.

One or more of the vehicle paths may be a railway line.

One or more of the vehicle paths may be a road.

The path-selection means may comprise a movable physical barrier such as a level-crossing barrier, or a set of railway points, for example. Alternatively or additionally it may comprise a warning signal for indicating that access is denied to one or more of the intersection vehicle paths.

The actuating means may be arranged to be driven by a vehicle approaching the intersection so as to deny access to each path other than said first path. The actuating means may be arranged to be driven by a vehicle leaviny the intersection so as to permit access to one or more paths other than said first path.

The actuating means preferably includes pumping means arranged to be driven by the vehicle so as to supply pressurised hydraulic fluid to a hydraulic accumulator, and a hydraulic actuator coupled to the path-selection means and supplied with working fluid by the hydraulic accumulator. Preferably the hydraulic accumulator has sufficient capacity to store energy derived from the multiplicity of vehicle crossings. Thus sufficient power is then available to operate the path selection means even when a vehicle of much lower than average speed or size of train or smaller number of vehicles drives the actuating means.

The pumping means may be a reciprocating pump arranged to be driven in successive strokes by rolling engagement with successive wheels of a passing train. Preferably said pumping means includes spring bias means so as to deliver pumping strokes only in the intervals between rolling engagement with successive wheels of the passing train.

Excessive shocks to the hydraulic system are thereby avoided.

According to another aspect of the present invention a section of a locomotive rail is provided with an actuating lever, said actuating lever being arranged in use to be engaged by rolling contact with a wheel of the train and thereby to perform useful work.

Preferably said actuating lever is arranged to engage the flange of a wheel of the train. Preferably said actuating lever extends generally parallel to said rail but is initially inclined relative to its bearing surface so as to tilt gradually as the flange of said wheel rolls over it.

The locomotive rail and actuating lever of the second aspect of the invention may be incorporated in the system of the first aspect of the invention.

A number of embodiments of the invention will now be described by way of example with reference to Figures 1 to 5A of the accompanying drawings, of which: Figure 1 is a sketch perspective view showing a level crossing incorporating a system in accordance with the invention; Figure2 is a diagrammatic representation of one actuator arrangement in accordance with the invention; Figure 3 is a diagrammatic representation of another actuator arrangement in accordance with the invention; Figure 4 is a diagrammatic representation of yet another actuator arrangement in accordance with the invention, and Figure 5 is a diagrammatic representation of a further actuator suitable for use in an arrangement in accordance with the invention.

Referring to Figure 1, the arrangement shown comprises a railway 1 and a road 22 which intersect at a level crossing 3. A pair of hydraulically operated level-crossing gates 4 are controlled by respective hydraulic actuators 5, which are supplied with pressurized hydraulic fluid from a hydraulic accumulator 6. Accumulator 6 is kept pressurised by a hydraulic pump 7, which is located adjacent one of the rails 1a and is arranged to be driven by engagement with the wheels of a passing train, as will subsequently be described in detail. Thus the level crossing gates 4 are arranged to block one of the two intersecting vehicle paths (railway 1 and road 2) under the control of an actuating system (actuators 5, hydraulic accumulator 6 and pump 7) in response to the passage of a vehicle along one of the intersecting paths.It will be appreciated that the arrangement of Figure 1 could be altered by locating the pump 7 in the road 2 and adapting itto be driven by the passage of road vehicles, and that the actuators 5 may be triggered by a relay-controlled electricaily operated valve (not shown) in response to any suitable electrical control signal. This electricat control signal may optionally be generated by passage of a train over pump 7. Irrespective of the precise manner in which gates 4 are controlled, it will be appreciated that they may be arranged to close in response to passage of a train over pump 7 in direction A, and!or to open in respnse to passage of a train over pump 7 in direction B.

It is envisaged that in some cases the level crossing gates may be controlled entirely by two pumps 7 located upline and down-line with respect to the level crossing and arranged to open the gates 4 only when a train passes over one of them in the direction away from the level crossing. In order to make such a system fail-safe it would be necessary to eliminate any power storage capacity- thus the hydraulic accumulator 6 would be omitted.

However in general the modest amounts of electrical power required at the level crossing for signalling and control purposes may be provided by a relatively small and inexpensive solar cell array or wind turbine in conjunction with a suitable storage battery (not shown). The hydraulic accumuator 6 is preferably of sufficient capacity to store power der-ived from the passage of a number of trains.

Figure 2 shows schematically one possible pump arrangement. A hardened ball-bearing 8 is located in a vertical recess in the upper surface of rail 1 a and bears against the inclined surface of a push-rod 9, which is in turn connected to a hydraulic piston 10.

Thus the wheel of a train rolling over ball-bearing 8 pushes piston 10 to the right as shown in Figure 2, against the action of a compression spring 11.

Consequently hydraulic fluid is drawn into a hydraulic cylinder 13 from a sump (not shown) via a non-return valve 12. When the wheel rolls away from ball-bearing 8 the spring-loaded piston 10 is released and forces hydraulic fluid into accumulator 6 via non-return valves 14 and 15. Thus the pumping stroke of pump 7 may be much slower than the return stroke, since it can take place in the interval between passage of successive bogies over the ball-bearing. The actuators for the level crossing gates are powered by fluid from hydraulic accumulator 6 and are controlled by a solenoid operated valve 16.

Figure 3 shows a different arrangement, in which generally L-shaped actuating lever 18 is pivoted at 19 in a slot in rail 1 a. The top surface of rail 1 a is cut away to accomodate the shorter leg of lever 18, so that the upper surface of the latter lies flush with the upper rail surface when a wheel 17 passes over.

Lever 18 is pivotally connected to pump 7 at pivot 20, and thus performs useful work in response to the passage of a train along rail 1 a. The construction and operation of pump 7 are as shown in Figure 2, except that the pump is mounted on a supporting pivot 21.

Figures 4 and 4a show a preferred arrangement in which the piston rod 9 of a pump 7 is acted on by two oppositely inclined levers 22, 22a extending general ly parallel to and supported from rail 1a at pivots 23, 23a. As indicated in Figure 4a, the actuating levers are located to one side of the rail 1a so as to engage the flange but not the tread of a wheel 17 advancing in direction B. The arrangement, being symmetrical, works similarly when a wheel advances in the opposite direction. Since the levers 22, 22stilt only very slowly under the weight of the advancing wheel, pump 7 may be made powerful and slowacting. A further advantage of this arrangement is that the rail surface need not be machined.

Figure 5 shows another pumping arrangement arranged to engage the flange only of an advancing wheel 17. Atough resilient tube 24 of elastomeric material is supported on a platform 25 at one side of rail 1 a. Tube 24 communicates with a sump (not shown) via non-return vavles 26 and 27 andwith the hydraulic accumulator (not shown) via non-return valves 25 and 28. As wheel 17 advances in direction B, the tube 24 is initially compressed and consequently squeezes hydraulic fluid into the accumulator via valves 25 and 28. After the wheel passes valve 26, the section of tube between valves 25 and 26 expands to its original shape and draws in hydraulic fluid via valve 26 from the sump. Simultaneously the central portion of the tube is compressed and forces hydraulic fluid into the accumulator via valve 28.

When the wheel passes over valve 27 the reverse sequence of events occurs. Thus the arrangement works essentially as a peristaltic pump. Because-the wheel 17 will be travelling at a fairly high speed even near the level crossing, it is desirable for the tube 24 to be mounted so that its never squeezed completely shut but merely restricted by the flange of wheel 17, as shown in Figure 5A. In this Figure it is assumed for the sake af clarity that the axis of wheel 17 lies directly on the section lines A-A. It will be appreciated that the length of tube 24 may be made ajustable so as to enable the power generated by the arrangement to be varied.

Claims

1. A power generation arrangement comprising at least two intersecting vehicle paths, path selection means for selectively permitting and denying access to said vehicle paths, and actuating means drivingly coupled to said path selection means, said actuating means being arranged to be energised in use by a vehicle moving in a first one of said paths and to provide power to enable said path selection means to permit or deny acess to at least one of said paths.

2. An arrangement as claimed in Claim 1' wherein said actuating means are arranged to trigger said path selection means in response to passage of said vehicle, so as to permit or deny access to one of said paths.

3. An arrangement as claimed in Claim 1 wherein said path selection means are triggered manually.

4. An arrangement as claimed in Claim 1 wherein said path selection means are arranged to be triggered in response to an electrical signal.

5. An arrangement as claimed in any preceding claim wherein one or more of said vehicle paths is a railway line.

6. An arrangement as claimed in Claim 1,2,3, or 4 wherein one or more of said vehicle paths is a road.

7. An arrangement as claimed in any preceding claim wherein said path selction means comprise a movable physical barrier.

8. An arrangement as claimed in Claim 5 wherein said path selection means comprise a set of railway points.

9. An arrangement as claimed in any preceding claim wherein said actuating means are driven by a vehicle approaching the intersection so as to cause said path selection means to deny access to each path other than said first path.

10. An arrangement as claimed in Claim 9 wherein said path selection means comprise a warning signal for indicating that access is denied to one or more of said vehicle paths.

11. An arrangement as claimed in Claim 9 including a warning signal for indicating that access is denied to one or more of said vehicle paths.

12. An arrangement as claimed in any one of Claims 1 to 8 wherein said actuating means are driven by a vehicle leaving the intersection so as to cause said path selection means to permit access to one or more of said paths other than said first path.

13. An arrangement as claimed in any preceding claim wherein said actuating means include pumping means arranged to be driven by the vehicle so as to supply pressurised hydraulic fluid to a hydraulic accummulator, and a hydraulic actuator coupled to the path-selection means and supplied with working fluid bythe hydraulic accummulator.

14. An arrangement as claimed in Claim 13 wherein said hydraulic accummulator has sufficient capacity to store energy derived from a multiplicity of vehicle crossings.

15. An arrangement as claimed in Claim 13 or 14 wherein said pumping means comprise a reciprocating pump arranged to be driven in successive strokes by rolling engagement with successive wheels of a passing train.

16. An arrangement as claimed in any of Claims 13, 14 and 15 wherein said pumping means includes spring bias means so as to deliver pumping strokes only in the intervals between rolling engagement with successive wheels of the passing train.

17. An arrangement as claimed in any of Claims 1 to 5 or 7 to 16 comprising a section of a locomotive rail provided with an actuating lever, said actuating lever being arranged in use to be engaged by rolling contact with a wheel of the train and thereby to perform useful work.

18. An arrangement as claimed in Claim 17 wherein said actuating lever is arranged to engage the flange of a wheel.

19. An arrangement as claimed in Claim 17 or 18 wherein said actuating lever extends generally parallel to said rail but is initially inclined relative to its bearing surface so as to tiit gradually as said wheels roll over it.

20. An arrangement for power generating substantially as hereinbefore described with reference to Figures 1 and 2, 1 and 3, 1 and 4, or 1 and 5 of the accompanying drawings.