GB2158794A

GB2158794A - Suspended trackway running gear having adjustable width spacing wheels

Info

Publication number: GB2158794A
Application number: GB08510846A
Authority: GB
Inventors: Bernhard Horstmann
Original assignee: Mannesmann AG
Current assignee: Vodafone GmbH
Priority date: 1984-05-19
Filing date: 1985-04-29
Publication date: 1985-11-20
Also published as: IT1184998B; FR2564384B1; IT8520754A0; GB2158794B; FR2564384A1; GB8510846D0; DE3418800C1

Abstract

Running gear for a suspended trackway system includes A pair of running wheels 3 rotatably mounted on a respective wheel support 1, 2 which are connected together by a cross-piece 6, the cross-piece being adjustably mounted in respective bores 16 in the wheel supports. Each wheel support is detachably locked to the cross-piece by means of a respective wedge 10. Each of the wedges 10 is mounted in a bore 15 in the associated wheel support, the bores 15 intersect the associated bore 16 so that the cross-piece 6 is engageable with the associated wedge (10). Each bore (15) has a screw-threaded portion (11) which is engageable with a setting screw 12 which acts on the associated wedge 10 for moving said wedge into engagement with the cross-piece. The wheel supports can be moved along the cross-piece, and then locked thereto, in any desired position, by driving in the wedges using the setting screws. <IMAGE>

Description

SPECIFICATION Running gear This invention relates to running gear for a suspended trackway system.

Running gear of this type has a pair of running wheels, each of which is rotatably mounted on a respective wheel support. The wheel supports are connected together by a cross-piece, which is used to support a load beneath the trackway system.

The running wheels run upon the lower flanges of a rail having, for example, an I-shaped cross-section. To compensate for differences in the width of such rails, it is desirable to provide means for adjusting the spacing between the running wheels.

One known way of adjusting the wheels is for the wheel supports to be mounted adjustably on the cross-piece. The wheel supports are then secured in position relative to the cross-piece, by driving pins through bores in the supports and the crosspiece. Unfortunately, it is difficult to ensure that the wheel supports can be adjusted to all possible track widths, whilst ensuring reliable guidance of the load supported by the running gear.

The aim of the invention is to provide running gear which is such that smooth alteration of track width can be achieved at low cost, and with reliable guidance of the load.

The present invention provides running gear for a suspended trackway system, the running gear having a pair of running wheels, each of which is rotatably mounted on a respective wheel support, the wheel supports being connected together by a cross-piece, the cross-piece being adjustably mounted in respective first bores in the wheel supports, each wheel support being detachably locked to the cross-piece by means of a repsective wedge, each of the wedges being mounted in a second bore in the associated wheel support, each of the second bores intersecting the associated first bore so that the cross-piece is engageable with the associated wedge, wherein each second bore has a screw-threaded portion which is engageable with a setting screw which acts on the associated wedge for moving said wedge into engagement with the cross-piece.

With this running gear, the surface pressure between the wedges and the cross-piece, which can be exerted by the setting screws, is sufficient to ensure the cross-piece to the wheel supports.

Moreover, the use of the wedges permits infinite variation of the distance between the wheel supports. This capacity for smooth adjustment enables the clearance between the flanges of the suspended rail along which the running gear runs and the flanges of the running wheels to be infinitely adjustable. Thus axial movement of the wheel supports on the cross-piece enables said clearances to be maintained independently of the flange width tolerances of the rail, which are sometimes large.

Advantageously, the screw-threaded portion of each second bore is longer than that of the associated setting screw, and extends from the mouth of that bore. Preferably, each setting screw is a grub provided with a hexagonal aperture in the end thereof. Alternatively, each grub screw may have a screwdriver slot in the end thereof.

If adequate fixing cannot be achieved with simple wedges, the edges thereof can be designed as knife edges which cut into the cross-piece when the wedges are forced in. In this case, each wedge may have a wedge-shaped surface for engaging the cross-piece, said wedge-shaped surface having a knife-edged portion which, in use, cuts into the cross-piece. The knife-edged portion of each wedge-shaped surface may be defined by the boudary of a level flattened region, a concave hollow region, or an obtuse-angled hollow region. The knife-edged portions are made of harder material than that of the cross-piece, and dig into the external surface of the cross-piece when the wedges are forced in. Quasi-positive locking is thus achieved, and can withstand high axial forces.The positive locking means produces grooves in the crosspiece, which do not normally have an adverse effect during adjustment to different track widths.

However, if they prevent slight adjustment of the track width, this defect can be overcome by turning the cross-piece slightly bringing a different region of its external surface into the region of the knifeedged portions.

When the above-mentioned pressure or cuttingin connection is loaded in the axial direction of a wedge beyond the restrictions of static friction, that wedge attempts to move axially in the first bore of the associated wheel support, and this leads to additional securing.

Advantageously, each wedge-shaped surface is inclined to the longitudinal axis of the associated wedge by an angle of substantially 5". Conveniently, the first and second bores of each wheel support intersect to define a segment of the circle of said first bore, the height of said segment being substantially 5- of the diameter of said first bore.

The running gear may further comprise a loadcarrying means supported by the cross-piece, the load carrying means being provided with a bore for receiving the cross-piece, and being detachably secured to the cross-piece. Advantageously, the load-carrying means is detachably secured to the cross-piece by means of a wedge. Preferably, said wedge is of the type defined above. A connection of this type enables the cross-piece to turn in the wheel supports, while the load-carrying means always hangs vertically.

Running gear constructed in accordance with the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure l is an end elevation of the running gear; Figure 2 is a cross-section taken on the lines ll-ll of Figure 1; Figure 3a is a cross-section taken on the lines lil- 111 of Figure 2; and Figures 3b and 3c are cross-sections similar to that of Figure 3a, but showing, on an enlarged scale, modifications.

Referring to the drawings, Figure 1 shows a suspended overhead trackway system comprising a rail of I-shaped cross-section having a vertical web 4 and lower flanges 5. Loads are supported beneath the rail by running gear including a pair of wheels 3 which are provided with flanges 9. The wheels 3 are rotatably mounted on wheel supports 1 and 2, for travel along the lower flanges 5 of the rail. The wheel 3 associated with the wheel support 2 is connected to gearing 20 of a drive motor (not shown). A cross-piece 6, of a circular cross-section, carries the wheel supports 1 and 2, as well as a load-carrying means 7. Each of the wheel supports 1 and 2 has a circular bore 16 through which the cross-piece 6 passes. The load-carrying means 7 is fixed in position by collars 18 and screws 19.During assembly of the running gear, the wheel supports 1 and 2 are positioned on the cross-piece 6 to establish a predetermined clearance 8 between each of the wheel flanges 9 and the edge of the associated rail flange 5.

Each of the wheel supports 1 and 2 has an additional circular bore 15 which houses a respective wedge 10. As shown in Figures 1 and 2, each bore 15 intersects the edge region of the associated bore 16. The intersecting region of the bores 15 and 16 of each wheel support 1, 2 defines a segment 17 of a circle, in which region the cross-piece 6 engages a wedge-shaped surface 13 of the associated wedge 10.

The wedges 10 are forced into engagement with the cross-piece 6 by means of setting screws 12 which are screwed into screw-threaded end portions 11 of the bores 15. Each wedge-shaped surface 13 extends at an angle of about 5" to the longitudinal axis of the associated wedge 10. The height of each segment 17 is about 5- of the diameter of the associated bore 16.

During assembly of the running gear, the required clearances 8 are set by adjusting the positions of the wheel supports 1 and 2 relative to the cross-piece 6. The setting screws 12 are then screwed into the threaded end portions 11, thereby pressing the wedges 10 against the cross-piece 6.

As this happens, knife-edged portions 14 of the wedges 10 dig into the external surface of the cross-piece 6. The knife-edges portions 14 can be level flattened regions 14a (see Figure 3a), concave hollow regions 14b (see Figure 3b) of obtruse-angled hollow regions 14c (see Figure 3c). The form of knife-edge portion is selected in dependence upon the materials of the wedges 10 and the crosspiece 6. The setting screws 12 can have screwdriver slots (see Figure 1) or internal hexagons (see Figure 2), by means of which they can be screwed into the threaded end portions 11.

Claims

1. Running gear for a suspended trackway system, the running gear having a pair of running wheels, each of which is rotatably mounted on a respective wheel support, the wheel supports being connected together by a cross-piece, the cross-piece being adjustably mounted in respective first bores in the wheel supports, each wheel supportbeing detachably locked to the cross-piece by means of a respective wedge, each of the wedges being mounted in a second bore in the associated wheel support, each of the second bores intersecting the associated first bore so that the cross-piece is engageable with the associated wedge, wherein each second bore has a screw-threaded portion which is engageable with a setting screw which acts on the associated wedge for moving said wedge into engagement with the cross-piece.

2. Running gear as claimed in claim 1, wherein the screw-threaded portion of each second bore is longer than that of the associated setting screw, and extends from the mouth of that bore.

3. Running gear as claimed in claim 1 or claim 2, wherein each setting screw is a grub screw provided with a hexagonal aperture in the end thereof.

4. Running gear as claimed in any one of claims 1 to 3, wherein each wedge has a wedgeshaped surface for engaging the cross-piece, said wedge-shaped surface having a knife-edged portion which, in use, cuts into the cross-piece.

5. Running gear as claimed in claim 4, wherein the knife-edged portion of each wedge-shaped surface is defined by the boudary of a level flattened region.

6. Running gear as claimed in claim 4, wherein the knife-edged portion of each wedge-shaped surface is defined by the boundary of a concave hollow region.

7. Running gear as claimed in claim 4, wherein the knife edged portion of each wedge-shaped surface is defined by the boundary of an obtruse-angled hollow region.

8. Running gear as claimed in any one of claims 4 to 7, wherein each wedge-shaped surface is inclined to the longitudinal axis of the associated wedge by an angle of substantially 5'.

9. Running gear as claimed in any one of claims 1 to 8, wherein the first and second bores of each wheel support intersect to define a segment of the circle of said first bore, the height of said segment being substantially 5% of the diameter of said first bore.

10. Running gear as claimed in any one of claims 1 to 9, wherein the wedges provided in the wheel supports are arranged to act in opposite directions.

11. Running gear as claimed in any one of claims 1 to 10, further comprising a load-carrying means being provided with a bore for receiving the cross-piece, and being detachably secured to the cross-piece.

12. Running gear as claimed in claim 11, wherein the load-carrying means is detachably secured to the cross- piece by means of a wedge.

13. Running gear for a suspended trackway system, the running gear being substantially as hereinbefore described with reference to, and as illustrated by, the accompanying drawings.