GB2167022A - Improvements in or relating to bogies - Google Patents

Abstract

A bogie 10 has fore and aft wheels 13, 14 each on a respective axle 19 which is supported on both sides of the wheel in parallel spaced members 20, 21 of frame 12 which is connected to a suspension device 15 on which may be mounted a chassis or the like. The suspension may include axle 42 on which the frame can pivot. A vehicle may have two such bogies respectively on opposite sides. <IMAGE>

Description

SPECIFICATION Improvements in or relating to bogies This invention relates to bogies particularly but not exclusively to wheeled bogies for trailers.

According to this invention a bogie unit comprises a frame providing axle support on both sides of two wheels, the wheels being rotatable on spaced axles, the axles being supported by the frame on both sides of each wheel to provide the support.

The frame may comprise parallel members.

The frame may be pivoted on an axis between the wheels.

There may be a suspension device connected to the frame between the wheels, said frame being pivotable about said axis with respect to the suspension device.

The invention also includes a bogie comprising two such bogie units spaced and respectively connected to a movable unit, for example a trailer, caravan or other vehicle.

The invention includes a vehicle including such a bogie.

The invention may be performed in various ways and two specific embodiments with possible modifications will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 is a plan view of a suspension unit; Figure 2 is a view from the right of Figure 1; Figure 3 is a plan view of a chassis and bogie; Figure 4 is a plan view of a bogie; Figure 5 is a side view of Figure 4; Figure 6 is a section on the line A-A of Figure 5; Figure 7 is a vertical section of the main pivot shaft of Figure 4; Figure 8 is a section of part of a hub; Figure 9 is a horizontal section of part of the bogie; and Figure 10 is a front view showing a modified hub arrangement.

Referring to Figures 1 to 9, a bogie 10 comprises two frames 11, 12 each supporting fore and aft wheels 13, 14 and connected to a suspension device 15 connected to support a chassis or other unit 16. For example the unit 16 could be the body of a caravan or a chassis for a trailer having a draw bar 17 with coupling 18. Each wheel 13, 14 can rotate on a respective axle 19 which in the present case is supported in the frame 11 or 12 on both sides of the wheel.

In more detail, frames 11, 12 are basically the same and have inner and outer parallel elongate members 20, 21 connected near their ends by tie bars 22 in spacer tubes 23, the tie bars 22 being held in place by nuts 24.

Wheels 13, 14 each has a hub 25 rotatable on bearings 26 on axle 19 which has an externally threaded part 27 secured at its end in the frame member 21 and held by nut 28. The inner end of the axle is for example welded at 28a to the frame member 20. A tube 29 may extend along the inner end of axle 19 and may be smooth or internally threaded on the axle, being a tight fit between bar 21 and nut 30. A dust cap 31 is provided.

In the arrangement shown the suspension unit is the Knott Beam configuration, which comprises of a tube axle beam 40 which extends across the chassis and in which is a rubberised suspension element supporting an inner bar 41 which engages at each end with a swing arm 43 which carries the lateral stub axle 42 on which bearings 44 and 45 that are secured to frame members 20 and 21 by bolts 47 can rotate.

The frames 11, 12 can thus rock or pivot on the respective axles 42. Axle 42 passes through beam 21 with a clearance fit and is secured by a lock nut.

Axle 42 passes through beam 20 with a clearance fit and is supported by flange bearing 44.

In a modification shown in Figure 10, the wheels have a conical brake drum assembly 50. Suitable braking devices are provided as is conventional.

Other forms of suspension unit can be used, for example a unit sold under the name Indespension, or a leaf spring with a beam axle or a torsion bar suspension arrangement.

Wheels of any size can be accommodated, as can brake drums and hubs, including conical drums fitted with low profile wheels and tyres.

The bogie can be adapted to be fitted to any device that has to be moved on wheels, horizontal, vertical, or suspended, moved by hand, by mechanical means, or any other means, pulled or pushed, braked or unbraked.

Primarily the bogie is designed for trailer application, and is arranged to keep all the wheels in contact with the ground substantially at all times, and under all conditions, thus the load distribution between all the wheels is constant, as is the braking efficiency. The braking of a vehicle or trailer is only as good as the tyre contact with the ground.

The bogie consists of two beams, rigidly fastened together by tie bars, supporting two stub axles, and the whole assembly pivots on a centre axle 42.

The cradle formed by this assembly houses the wheel hubs, brake drums, and the wheels and tyres.

The inner beam 20 may be manufactured from box section steel, and the outer beam 21 from solid steel strip. These beams could be of any suitable section, solid or other, and can be fabricated from any suitable material, ferrous or non-ferrous, cast, pressed, forged, cut or moulded.

The wheel and brake assemblies are housed in a cradle or frame, and the stub axles, which are supported at both ends inner and outer, pass right through the wheel hubs, thus reducing the stress on the stub axle support, particularly when conical brake drums are used. This design greatly reduces the possibility of metal fatigue and weld fracture at the stub axle root.

The bogie would normally be provided with shock absorbers (fore or aft, or both fore and aft) for example between the chassis unit and the inner member 20 - preferably near the ends of the inner member.

Claims (8)

1. A bogie unit comprising a frame providing axle support on both sides of two wheels, the wheels being rotatable on spaced axles, the axles being supported by the frame on both sides of each wheel to provide the support.

2. A bogie unit as claimed in Claim 1, in which the frame comprises parallel members.

3. A bogie unit as claimed in Claim 1 or Claim 2, in which the frame is pivoted on an axis be tween the wheels.

4. A bogie unit as claimed in any preceding Claim, comprising a suspension device connected to the frame between the wheels, said frame being pivotable about said axis with respect to the sus pension device.

5. A bogie unit substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

6. A bogie comprising two bogie units as claimed in any preceding claim, said bogie units being spaced and respectively connected to a mov able unit.

7. A vehicle including a bogie as claimed in Claim 6.

8. A vehicle having a bogie unit as claimed in any of Claims 1 to 5.