GB2027656A - Improvements in heavy duty rail vehicles - Google Patents

Abstract

A heavy duty rail vehicle has a super-structure 1 supported on a bogie 5 by way of bearing including an upper bearing member 2 and a lower bearing member 8 with a projection or rib 15 extending transversely to the longitudinal axis of the bogie. The projection rests on the bogie within a channel defined by shoulder pieces 6 and is shaped to allow the bearing to tilt forwards and backwards to permit adjustment of the super-structure relative to the bogie. <IMAGE>

Description

SPECIFICATION Improvements in heavy duty rail vehicles This invention relates to a heavy duty rail vehicle, for example, a truck for use in a metallurgical works and in particular is concerned with a bearing by means of which an upper chassis part may be supported on a lower chassis part for example a bogie.

Bearings of the type to which the invention relates allow the upper chassis part to turn relative to the lower chassis part when the vehicle negotiates curves in the track and ramps. The bearings are also arranged to accommodate other relative movement between the two chassis parts for example those caused by irregularities in the rails and deformation of either chassis part and between which the bearings are connected.

Various forms of such bearings are known. One form, used especially in the United States, has upper and lower bearing members with planar contact faces so that adjustment can take place only in the horizontal plane. All other movements of the chassis are accommodated by suspension elements or by adjustment of the axles relative to the lower chassis part. The distribution of forces when adapting to different springing is, however, irregular and therefore unfavourable.

It is also known to employ a bearing having a hemispherical bearing member which is received within a complementary socket. Although such a spherical bearing has the advantage that it permits relative movement to take place in more than one plane, it has the disadvantage that transmission forces depend upon the radius of the bearing member and upon friction. In a multi-axle vehicle, considerable axle pressure differences may result from frictional moments. In heavy trucks which are used currently, especially in metallurgical works, and in which the axle pressures may be at least 50 tonnes, such pressure differences are a serious disadvantage for the rail installation.

Modern heavy duty trucks, for example slag trucks, torpedo trucks and tubular ladle trucks often have a rotatable super structure, or a chassis which is torsionaily flexible and it is sufficient to accommodate tilting movements of the super structure relative to the track solely in the direction of the longitudinal axis of the truck.

It is therefore an object of the present invention to provide a bearing which allows the lower part of the chassis to adjust relative to the track in a satisfactory manner and in which the frictional moments which do occur are considerably less than in the known bearings.

Accordingly, the bearing comprises a support member to be mounted on a lower chassis part (or which may form part of a lower chassis part), a lower bearing member which rests on the support member and an upper bearing member which cooperates with the lower bearing member, and is intended to be secured to a load bearing member, the lower bearing member having on its underside a projection which in use extends transversely of the longitudinal axis of the lower chassis part and is received in a channel in the support member, the underside of the projection being shaped to enable the lower bearing member to tilt on the base of the channel in the forward and rearward directions.With this arrangement, it is possible for the lower part of the chassis to adapt relative to the track and for the upper part of the chassis to adjust relative to the lower part of the chassis in every position and with all permissable loadings.

Because the lower bearing member is arranged to - tilt on the support member, (rather than slide as in the case of a spherical bearing) the adjustments that take place in the longitudinal direction meet with very little resistance. As a result, the parts of the vehicle tend to adjust even when there are only slight differences in axle loadings. When the lower chassis part consists of several bogies, each can adapt in an ideal manner relative to the track in the longitudinal axis of the vehicle. Where slight differences in height occur transversely to the axis of the track within the region of the bogie or chassis such as may occur even with well laid rails, these inaccuracies can be accepted by the springing of the vehicle.

In the event of difficult track conditions, the bearing provided by the present invention may be combined with a known spherical bearing to permit transverse adjustment. For example, the bearing may have three bearing planes, the lowest a spherical bearing. However, even with such a combination, the advantage provided by the present invention of low resistance to tilting is still considerable.

The invention will now be described in greater detail but by way of example only with reference to the accompanying drawings, wherein, Figure 1 is a section through a bearing embodying the invention taken in the vertical longitudinal centre plane of the vehicle, Figure 2 is a front view of the bearing shown in Figure 1 but with the forward shoulder piece omitted, and Figure 3 is a plan view of the bearing shown in Figure 1 but with the upper parts omitted.

Referring to the drawings, a vehicle, for example, a slag truck or a torpedo truck of a metallurgical works, includes an upper chassis 1 and a lower chassis 5. Relative movement is to be allowed to take place between the two chassis parts. Typically, the lower chassis part consists of a number of bogies, each of which is independently adjustable relative to the upper chassis part. For convenience herein, the part 5 will be referred to as the bogie and the part 1 as the superstructure.

A bearing for permitting adjustment of the superstructure relative to the bogie comprises an upper bearing 2, a lower bearing member 8, and a support member which, in the illustrated embodiment forms part of the bogie 5 but may be a separate component mounted on the bogie. The upper member 2 consists of a fiat, circular plate with a central aperture 3 bolted to the underside of a load-bearing member of the superstructure. A ring 4 welded to the superstructure serves to locate and centre the upper member 2. The upper member 2 is received within a recess in the lower bearing member The lower member has a rim 20 which closely surrounds the upper member and which has a chamfer to facilitate location of the superstructure relative to the bogie during assembly.The contact faces 9 and 10 of the lower and upper bearing members respectively are planar and finely machined so that sliding movement readily takes place as relative rotation occurs. The contact surfaces are lubricated by oil supplied to and drained from the surfaces by way of ducts and grooves 11 in the surface 10. The upper and lower bearing members have central, coaxial bores of substantially equal diameter, 3 and 12, respectively, through which passes with a substantial clearance a bolt 13 screwed into a bar 14 fixed to the upper surfaces of the support member constituted in this case by the bogie 5.

The under surface of the lower bearing member 8 is formed with an integral diametral projection which extends transversely to the longitudinal axis of the bogie. The lower surface of the projection has two planar surfaces 1 8 arranged at an obtuse angle to each other and both of which merge into an arcuate surface 1 7 which may lie in the surface of an imaginary cylinder or have other arcuate shape. With the bearing in its normal position shown in Figure 1 the bearing may tilt in either direction, the surface 17 rolling on the surface of the support member until one or other planar surface 18 makes contact with the surface of the support member. The angle between the surface of the support member and the surface 18 therefore determines the extent to which the bearing may tilt.The projection 1 5 is located within a channel bounded by two parallel shoulder pieces 6 welded to the support member. The sides of the projections which extend transversely to the longitudinal axis of the bogie are curved around one or more horizontal axes and slide in contact with complementary surfaces of the shoulder pieces 6.

The transverse bar 14 is housed within a recess 19 in the bottom of the bearing member 8.

The clearance between the bar and the sides of the recess in which it is received is a minimum in the direction transverse to the longitudinal axis of the bogie, but, in the direction parallel to said axis, is sufficiently great to permit the bearing member to tilt without restriction.

Reference is made to our application number P283501 3.2 filed in the Federal Republic of Germany to the extent that the said application includes subject matter not described herein.

Claims (7)

1. In a heavy duty rail vehicle, a lower chassis part on which an upper chassis part is supported by way of a bearing comprising a support member forming part of the lower chassis part, or being mounted thereon, a lower bearing member which rests on the support member and an upper bearing member which co-operates with the lower bearing member and is secured to the upper chassis, part, the lower bearing member having on its underside a projection which extends generally transversely of the longitudinal axis of the lower chassis part and is received in a channel in the support member, the upper surface of the projection being shaped to enable the bearing member to tilt on the base of the channel in the directions forwardly and rearwardly of the vehicle.

2. In a heavy duty rail vehicle, a bogie on which a load-bearing member is supported by way of a bearing, comprising a support member forming part of the bogie or being mounted thereon, a lower bearing member which rests on the support member and an upper bearing member which cooperates with the lower bearing member and is secured to the load bearing member, the load bearing member having on its under side a projection which extends generally transversely of the longitudinal axis of the bogie and is received in a channel in the support member, the under surface of the projection being shaped to enable the bearing member to tilt in the forward and rearward direction.

3. A vehicle as claimed in Claim 1 or Claim 2 wherein the under surface of the projection has two planar surfaces at an angle to each other and both merging into an arcuate surface which rests on the base of the channel when the bearing is in a central position.

4. A vehicle as claimed in any preceding claim, in which the upper bearing member is in the form of a circular plate, both bearing members having planar, contact surfaces.

5. A vehicle as claimed in any preceding claim, wherein the flanks of the projection which extend transversely to the said longitudinal axis are cylindrically curved and slide in contact with complimentary surfaces forming the sides of the channel.

6. A bearing for a heavy duty rail vehicle particularly a metallurgical truck with a loadbearing member rotatably mounted on the bogie or with a torsionally flexible chassis, the bearing having an upper part connected to the loadbearing member and a lower part which is spatially movable relative to the upper part connected to the bogie, the upper part being formed as a circular plate with a flat lower surface which co-operates with a corresponding surface of the lower part, the lower face of which has a projection extending diametrally transversely of the longitudinal axis of the bogie, the bearing surface of which projection is a portion of a roll surface which continues at each side into a plane surface, which, in the central position of the bearing makes with the upper base surface of the bogie an angle which is equal to the maximum deflection of the bearing, the cylindrical formed flanks of the projection co-operating with complementary inner side faces of shoulder pieces extending parallel to the longitudinal axis of the projection and firmly connected to the bogie.

7. A bearing in accordance with any embodiment of the invention (or modification thereof) described and/or illustrated herein.