GB2137950A

GB2137950A - A Tubular Belt Conveyor, more particularly for Underground Mine Workings

Info

Publication number: GB2137950A
Application number: GB08408015A
Authority: GB
Inventors: Friedrich Wilhelm Paurat; Roland Paurat
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-04-13
Filing date: 1984-03-28
Publication date: 1984-10-17
Also published as: DE3313301C1; GB8408015D0; GB2137950B

Abstract

A tubular belt conveyor, more particularly for underground mine workings, has at least one traction means (not shown) and a conveyor belt (1), which in the closed tubular state has a curved base (2) and converging flanks (3) and consists of a rubber or plastics material with textile reinforcing inserts (5). The conveyor belt is provided, near the borders (9) of the flanks (3) and optionally also through regions (8) towards the base (2) with a differential construction allowing extension on the outer arc and compression on the inner arc in curved paths, whereby harmful constraints can be eliminated, even in tight curves. The differential construction may be formed by low-stretch textile reinforcing inserts (10) transversely to the direction of transport, and textile inserts (11) in the direction of transport that allow both extension and compression. Alternatively, the differential construction can be formed by providing the flanks with corrugations. <IMAGE>

Description

SPECIFICATION A Tubular Belt Conveyor, More Particularly for Underground Mine Workings This invention relates to a tubular belt conveyor, more particularly for underground mine workings, having at least one traction means and a conveyor belt, in which the conveyor belt in the closed tubular state has a curved base and converging flanks and consists of rubber our a plastics material with textile reinforcing inserts.

Tubular belt conveyors of this type are known with guidance systems of both the single-rail conveyor version, as it is called (cf. GB-PS 2 1-1 6 1 37A) and the two-rail version (cf. GB-PS 2 100 693A). Alternatively, however, guide rails may be dispensed with in favour of stationary rollers, mounted for example in the roof area, over which the traction means is or are guided. The conveyor belt is connected either directly or indirectly to its traction means An arrangernent can be found whereby the tubular belt.conveyor can negotiate curves, even of small radius and providing deflection through up to 1800.However, experience has shown that in small-radius curves the flank regions of the conveyor belt are put under constraint, because the cònverging flanks, at least near the curved base, have to describe paths of differing length determined by the radius -of curvature in the curves. Under certain circumstances, these constraints have a deleterious effect on the guidance systems. There are no compensating means such as tube differentials in motor vehicles.

The object of the invention is to provide a tubular belt conveyor of the type in question in which harmful -constrains are no longer applied to the conveyor belt when negotiating curves, particularly curves of small radius and large deflection.

According to the present invention, the converging flanks of the conveyor belt have a differential construction allowing extension on the outer arc and compression on the inner arc in curved paths. Preferably, the differential construction is adopted in the converging flanks in the regions between the borders which carry the traction means and the curved base. More particularly, this denotes the region where the conveyor belt bellies out under its load of material transported. The extensibility and compressibility - of the conveyor belt in the bellying regions of the flanks exceed those in border regions, thereby conforming as required to the different radii of curvature.

A differential construction as proposed by the invention can be effected, in principle, in various ways. Thus it can be effected so that the flanks are profiled like a harmonica, i.e. corrugated with the ridges and troughs running transversely to direction of transport,-so that extension is brought about by drawing the corrugations apart and compression by urging them more closely together. However, it is also possible to devise a differential construction for uncorrugated conveyor belts. This embodiment of the invention is of independent significance. It is basically characterised in that the regions having a differential construction the flanks have low; stretch textile reinforcing inserts transversely and preferably at right angles to the direction of transport, together with textile inserts in the direction of transport that allow both extension and compression.Suitable yarns from which the reinforcing inserts can be made are known also in the textiles field as crimp yarns.

Outstandir.g simplicity and functional reliability can be achieved if the reinforcing inserts are formed as a woven fabric having its Weft strands at right angles to the direction of transport and its warp strands in the direction of transport. In this case, the number of warp strands per unit width (i.e., measured transversely to the direction of transport) can decrease from the base towards the borders, which carry the traction means, and the extensibility of the warp strands preferably increases from the base towards the borders. If one uses woven fabrics, the fabric sheets can also be laid in a plurality of layers. it is within the scope of the invention to leave certain areas devoid of warp threads.

Depending on the Shore hardness of the rubber or plastics material from which the conveyor belt is made, the features atready described should suffice,-when taken together, to achieve the differential action However, it can be advaritageous in combination with the features already described to adjust the Shore hardness of the rubber or plastics material specifically so that the Shore hardness of the material is lower near the borders of the flanks than near the base. The Shore hardness of the rubber or plastics material is also preferably lower in the flanks than within the base region. It is possible to adopt gradual transitions in hardness.If the conveyor belt in a tubular belt conveyor of the invention is constructed as just described, the conveyor belt can have the same thickness throughout; this is advantageous alike for-storage, spares maintenance and use, because care must always be taken in the operation of tubular belt conveyors to ensure that the conveyor belt can be closed into a tube but can equally well be opened for loading and unloading purposes, by laying the guide rails in a particular manner or guiding the traction means appropriately.

The accruing advantages are to beseen in that by virtue of the differential conveyor belt layout in a tubular belt conveyor of the invention there are no longer any harmful constraints in curves, even those with a small radius of curvature and large deflection. This prolongs the useful life of the conveyor belts, and moreover eliminates harmful loads on the curve guidance systems.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying diagrammatic drawings, in which Figure 1 is a perspective view of part of a tubular belt conveyor in accordance with the invention; Figure 2 is a plan view, on a smaller scale than Figure 1, of a curved region in the tubular belt conveyor; Figure 3 is a plan view of part of the conveyor belt after flattening out; Figure 4 shows a cross-section through the object of Figure 3; and Figure 5 is an enlargement of nart of Figure 4.

The tubular belt conveyor shown in Figures 1 and 2 is intended more particularly for underground mine workings. Eacn run comprises a conveyor belt 1, which in the closed tubular state has a curved base 2 and converging flanks 3. The conveyor belt consists of rubber or a plastics material 4 and has textile reinforcing inserts 5 (see Figures 3 to 5). The borders 9 of the conveyor belt 1 are connected to roller carriages 6, which run on guide rails 7, and traction means, not shown, engage on the roller carriages 6 on one or both sides, to propel the conveyor belt.

Referring to Figure 2, it becomes obvious that when such a tubular belt conveyor encounters a curve in the conveyor path the inner and outer sections must negotiate different radii of curvature. The outer radius of curvature R exceeds the inner radius of curvature r by an amount determined by the breadth of the loaded tubular belt conveyor. Harmful constraints in the conveyor belt 1 in the vicinity of such curves have been eliminated by virtue of the invention, which is, as Figures 3 and 4 show that the conveyor belt 1 has a differential construction in regions 8 in the flanks 3, i.e. between the borders 9 and the base 2. In conjunction with Figure 2, itcan be seen that the differential construction allows extension on the outer arc of the curve and compression on the inner arc of the curve. Within the base 2 there is no significant extension or compression. In this respect, the base forms as it were a neutral zone.

Figures 3 to 5 show how the differential construction is effected in detaii. It will be seen that the tube flanks have low-stretch textile reinforcing inserts 10 transversely to the direction of transport. In the direction of transport there are textile inserts 11 that allow both extension and compression. For this purpose, one can use textile inserts provided with so-called crimping. The extensibility and compressibility of the conveyor belt 1 in the bellying regions of the flanks 3 (i.e., adjacent the base 2) exceed those in the border regions 9. In designing the construction for these strains, the different radii of curvature must be allowed for.

Claims

1. A tubular belt conveyor having at least one traction means and a conveyor belt, in which the conveyor belt consists of rubber or a plastics material with textile reinforcing inserts and in the closed tubular state has a curved base and converging flanks, the converging flanks of the conveyor belt having a differential construction allowing extension on the outer arc and compression on the inner arc in curved paths.

2. A tubular belt conveyor as in Claim 1, wherein the differential construction is adopted in the converging flanks in regions between the borders which carry the traction means and the base.

3. A tubular belt conveyor as in either of Claims 1 and 2, wherein in the regions having a differential construction the flanks have lowstretch textile reinforcing inserts transversely to the direction of transport, the regions having a differential construction also having textile inserts in the direction of transport that allow both extension and compression.

4. A tubular belt conveyor as in any one of Claims 1 to 3, wherein the reinforcing inserts are formed as a woven fabric having its weft strands at right angles to the direction of transport and its warp strands in the direction of transport.

5. A tubular belt conveyor as in Claim 4, wherein the number of warp strands per unit width decreases from the base towards the borders.

6. A tubular belt conveyor as in either of Claims 4 and 5, wherein the extensibility of the warp threads increases from the base towards the borders.

7. A tubular belt conveyor as in any one of Claims 4 to 6, wherein fabric sheets are laid in a plurality of layers.

8. A tubular belt conveyor as in any one of Claims 1 to 7, wherein the Shore hardness of the rubber or plastics material is lower near the borders of the flanks than near the base.

9. A tubular belt conveyor as in Claim 8, wherein the Shore hardness of the rubber or plastics material is also lower in the flanks than within the region of the base.

10. A tubular belt conveyor as in any one of Claims 1 to 9, wherein the conveyor belt has the same thickness throughout.

11. A tubular belt conveyor substantially as hereinbefore described with reference to the accompanying drawings.