GB2078648A

GB2078648A - Railway vehicle track brake system

Info

Publication number: GB2078648A
Application number: GB8118714A
Authority: GB
Original assignee: Becorit Ltd
Current assignee: Spare IPG 15 Ltd
Priority date: 1980-06-28
Filing date: 1981-06-18
Publication date: 1982-01-13
Also published as: GB2078648B

Abstract

A rail vehicle body is mounted on a number of bogies, each of which has a brake shoe 26 which can engage the track 10. Front and rear wheels 13, 14 at the same side of the bogie are mounted on a common member 17 pivoted at a position between the wheels on a carrier 18 which can be moved downwardly by a piston and cylinder unit to raise the brake shoe clear of the track. <IMAGE>

Description

SPECIFICATION Railway vehicle This invention relates to a railway vehicle having a body, a plurality of pairs of wheels, the wheels of each pair engaging, in use, respective rails of a track on which the vehicle runs, a plurality of brake shoes engageable with the track in use and control means for raising the brake shoes relative to the wheels to permit the vehicle to run on the track without the brake shoes engaging the track. With this arrangement, the brake shoes automatically descend into engagement with the track if the control means fails. Usually, the brake shoes are urged toward the track by the action of gravity on the body and any load carried thereby.

A known railway vehicle of the kind referred to has a front pair of wheels mounted adjacent to one end of the vehicle body on arms which can swing upwardly and downwardly about a front pivot axis and a rear pair of wheels mounted adjacent to a rear end of the body on further arms which can swing upwardly and downwardly about a rear pivot axis.

According to the present invention, a railway vehicle of the kind referred to includes a pair of bogies, the bogies are connected with the railway vehicle body for swivelling relative thereto about respective swivelling axes which are generally upright in use and each bogie has a plurality of said pairs of wheels and a plurality of said brake shoes, the wheels of the bogie being so arranged that front and rear wheels of the bogie which engage with the same rail in use are movable upwardly and downwardly relative to the body about a common axis.

The radius of the path of the axis of rotation of each wheel may substantially exceed the wheel radius and preferably exceeds the wheel diameter.

The common axis about which the front and rear wheels move preferably lies midway between the front and rear wheels of the bogie.

Conveniently, bearings in which the front and rear wheels are mounted for rotation about respective axes are connected by a single connecting member which is itself mounted for pivoting about the common axis. With this arrangement, when one wheel pivots upwardly about the common axis the other wheel pivots downwardly.

In addition to provision for pivoting of the front and rear wheels about the common axis, provision may also be made for movement of the front and rear wheels together upwardly and downwardly relative to the body. The control means is conveniently arranged for controlling this upward and downward movement of the front and rear wheels together.

Examples of vehicle embodying the invention will now be described, with reference to the accompanying drawings wherein: FIGURE 1 shows diagrammatically a side elevation of one bogie of a vehicle, together with a part of a body of the vehicle and a part of the track on which the vehicle runs; FIGURE 2 shows certain parts of the bogie in cross-section on the line A-A of Figure 1; FIGURE 3 shows certain parts of the bogie in cross-section on the line B-B of Figure 2; and FIGURE 4 illustrates a modification of the bogie.

The vehicle illustrated in the accompanying drawings is intended for use on a track 10 in an underground mine working. The vehicle includes a body 11 supported near to its ends on front and rear bogies respectively, only one of these bogies being shown in the drawings. The other bogie may be identical with the one illustrated. Each bogie is connected with the vehicle body for swivelling relative thereto about a swivelling axis 12 which is generally upright in use and lies between the rails of the track 1 0.

The bogie illustrated in the drawings comprises a front pair of wheels, one of which is shown at 1 3 and a rear pair of wheels, one of which is shown at 14. The wheels 13 and 14 are mounted for rotation about respective axes of rotation, 1 5 and 16, on opposite end portions of a connecting member 1 7. The wheel axes 1 5 and 16 are fixed with respect to the connecting member 17. The wheels 13 and 14 are aligned with each other to engage with the same rail of the track 10. The other wheels of the bogie are mounted in a similar manner on a further connecting member (not shown).

The connecting member 1 7 is mounted at a position between its ends on a carrier 1 8 for pivoting relative thereto about a pivot axis 1 9 which is generally horizontal and transverse to the length of the track. Typically, the carrier 1 8 comprises a pair of side plates 20 between which the connecting member 17 lies, and a pivot 21 which extends from one of the side plates through a bearing opening in the connecting member 1 7 to the other side plate.

The carrier 18 is guided for movement upwardly and downwardly relative to the body 11 of the vehicle by guide elements 22 of the bogie.

The guide elements define a rectilinear path for the carrier. Provision may be made for adjustment of the guide elements and carrier laterally of the track to enable the vehicle to be used on tracks having somewhat different gauges. For example, there may be between the guide elements and further parts of the bogie packing pieces which can be removed or added to adjust the position of the guide elements. Alternatively, to enable the vehicle to be used on tracks having respective gauges which differ more significantly, the bogie may be provided for each carrier 1 8 with a plurality of sets of guide elements 22, the different sets being disposed at different distances from a longitudinal centreline of the vehicle. The carrier could then be engaged with any selected set of guide elements.

The bogie further includes control means for controlling downward movement of the vehicle body 11 relative to the carrier 1 8 and connecting member 17. The control means includes a transverse member 23, opposite end portions of which overlie the carriers 1 8 of the bogie.

Between each carrier and the adjacent end portion of the transverse member, there is provided a resiliently compressible device 24 which may comprise a metal spring or springs or a body of elastomer. The device 24 can contract resiliently to permit limited downward movement of the transverse member relative to the connecting member 17 and wheels.

The control means further comprises an hydraulic piston and cylinder unit 25 arranged with its axis vertical. The cylinder of the unit 25 is rigidly secured to a main part of the bogie and a piston of the unit is connected by a piston rod with the transverse member 23 at a mid position thereon.

There is also rigidly mounted on the main part of the bogie to occupy a position between the wheels 13 and 14 a brake shoe 26. When the piston and cylinder unit 25 is extended, the brake shoe 26 and vehicle body 11 are raised relative to the connecting member 17 so that the brake shoe is clear of the track 10. When the unit 25 is permitted to collapse, the action of gravity on the body 11 and any load carried thereby urges the brake shoe 26 into engagement with the track. A further brake shoe is arranged in a corresponding manner between the other wheels of the bogie.

By pivoting of the connecting member 17 about the pivot axis 1 9, the front and rear wheels 13 and 14 of the bogie which engage the same rail of the track can move together about the axis 1 9 relative to the remainder of the bogie and to the body 11.

If the wheel 13 rises relative to the pivot axis 1 9, the wheel 14 descends by an equal amount. In use, the upward and downward movement of the wheels by pivoting about the axis 19 is small, as compared with the distance separating each of the wheel axes 1 5 and 1 6 from the pivot axis 1 9.

Thus, the movement of the wheels approximates to vertical movement.

The wheels 13 and 14 can also move together upwardly and downwardly relative to the body 11 by contraction and expansion of the resilient device 24.

The bogie illustrated in Figures 1,2 and 3 may be modified to incorporate the control device illustrated in Figure 4. If a device as illustrated in Figure 4 is associated with each of the connecting members 17, the transverse member 23, compressible device 24 and piston and cylinder unit 25 would be omitted. The device illustrated in Figure 4 comprises a housing 27 which would be rigidly secured to the main part of the bogie. A cylinder 28 is mounted in that housing 27 for sliding upwardly and downwardly relative thereto.

The cylinder is urged downwardly relative to the housing by a spring 29.

In the cylinder 28, there is disposed a piston 30 connected by a piston rod 31 which extends through the lower end of the cylinder with an associated one of the carriers 1 8. When the cylinder 28 is charged with hydraulic fluid under pressure, the cylinder, housing 27, main part of the bogie and vehicle body 11 are raised relative to the carrier 1 8 and connecting member 1 9 so that the brake shoe 26 is raised from the track.

During use, limited upward and downward movement of the vehicle body 11 relative to the track is accommodated by flexing of the spring 29.

If the hydraulic fluid is released from the cylinder 28, the cylinder descends relative to the piston and the shoe 26 is lowered onto the track.

The vehicle described herein is suitable for use on tracks having bull-head rails and on tracks having assymetrical rails.

If required, the connecting member 1 7 may be mounted on the carrier 1 8 by means which biases the connecting member towards an equilibrium position in which the length of the connecting member is perpendicular to the path of movement of the carrier 18 along the guide elements 22. For example, the pivot may include a rubber bush which is stressed when the connecting member rocks relative to the carrier.

Claims

1. A railway vehicle having a body, a plurality of pairs of wheels, the wheels of each pair engaging, in use, respective rails of a track on which the wheel runs, a plurality of brake shoes engageable with the track in use and control means for raising the brake shoes relative to the wheels to permit the vehicle to run on the track without the brake shoes engaging the track, wherein the vehicle comprises a plurality of bogies, the bogies are connected with the vehicle body for swivelling relative thereto about respective swivelling axes which are generally upright in use, each bogie has a plurality of said pairs of wheels and a plurality of said brake shoes and front and rear wheels of the bogie which run on the same rail of the track are movabie upwardly and downwardly relative to the vehicle body about a common axis.

2. A vehicle according to claim 1 wherein the radius of the path along which the axis of rotation of a wheel moves upwardly and downwardly relative to the body substantially exceeds the radius of the wheel.

3. A vehicle according to claim 1 or claim 2 wherein the front and rear wheels of the bogie which engage the same rail of the track are arranged to move together about said common axis.

4. A vehicle according to claim 3 wherein said front and rear wheels are carried on the same member, which member can pivot about the common axis.

5. A vehicle according to any preceding claim wherein the front and rear wheels of a bogie which engage the same rail of the track can move upwardly and downwardly together relative to the vehicle body.

6. A vehicle according to claim 4 wherein said member is carried on a carrier for pivoting relative to the carrier about the common axis and wherein provision is made for supporting the carrier in a selected one of a plurality of alternative positions in which the distance between the carrier and a longitudinal centreline of the vehicle differs.

7. A rail vehicle substantially as herein described with reference to and as illustrated in Figures 1, 2 and 3 of the accompanying drawings.

8. A rail vehicle according to claim 7 modified substantially as herein described with reference to and as shown in Figure 4 of the accompanying drawings.

9. Any novel feature or novel combination of features disclosed herein or in the accompanying drawings.