GB2154531A - Scraper chain conveyor system - Google Patents

Abstract

A scraper chain conveyor system comprises a first conveyor 4, and a second scraper chain conveyor 26 extending orthogonally, or generally so, with respect to the first conveyor 4, with adjacent ends 16, 39 of the first and second conveyors 4, 26 overlapping one another at a cross-over junction and with the conveying and return runs 9, 10; 34, 35 of the first and second conveyors 4, 26 interleaved. The deck plate 12 of the first conveyor 4 terminates at a location above the conveying run 34 of the second conveyor 26 to define an absent deck plate area and continues beyond the conveying run 34 of the second conveyor 26. <IMAGE>

Description

SPECIFICATION Scraper chain conveyor system This invention relates to a scraper chain conveyor system and to an arrangement whereby a first, scraper chain conveyor discharges conveyed material onto a second scraper chain conveyor.

Scraper chain conveyors are used extensively in coal mining operations and conventionally a first scraper chain conveyor is located along the mineral face (which conveyor is usually termed the armoured face conveyor) and has an elevated discharge end at which coal is transferred onto a second and lower scraper chain conveyor located along a roadway defining one end of the mineral face (which second conveyor maybe a so-called stage loader, beam stage loader, or short length feeder conveyor) the second conveyor extending orthogonally, or generally so, to the first conveyor and discharging on to a belt conveyor extending the roadway.Although "end" discharge from the first conveyor to the second conveyor has been practiced for many years, with coal etc., thrown over the delivery end of the first conveyor onto the second conveyor the technique requires that the coal be turned through 90" at the point of discharge/delivery and conveyance is frequently interrupted, due to jamming problems, as irregularly sized coal lumps are involved, and furthermore, although higher elevation of the discharge end of the first conveyor would avoid the disadvantageous tendency for the return run of the first conveyor to drag coal back off the second conveyor, the limited height available at a mine frequently dictates that the discharge end of the first conveyor is unavoidably located in close proximity to the conveying run of the second conveyor.

Consequently, in more recent times, attempts have been made to effect "side" discharge, in contrast to end discharge, but this requires a crossover junction at the adjacent ends of the first conveyor and second conveyor. The cross-over junction may be of a first kind in which the first conveyor is located above the second conveyor, with a pitched (inverted "V") deck plate to cover the return run of the first conveyor. In a second junction kind the conveying and return runs of both conveyors are interleaved and a flat, central land or bridge piece, narrower than the normal deck plate width is provided to support the chain strand(s) and the centre portions of its flight bars, but this land or bridge piece still presents an obstruction to coal delivery from the first conveyor.

The object of the present invention is to provide an improved scraper chain conveyor system.

According to the present invention, there is provided a scraper chain conveyor system comprising a first scraper chain conveyor, and a second scraper chain conveyor extending orthogonally, or generally so, with respect to the first conveyor, both the first and the second conveyors incorporating at least one tensioned drive chain with a plurality of transversely extending flight bars attached thereto at longitudinally spaced apart locations, with adjacent ends of the first and second conveyor overlapping one another at a cross over junction and with the conveying and return runs of the first and second conveyors interleaved so that the conveying run of the first conveyor lies above the conveying run of the second conveyor, the conveying run of the second conveyor lies above the return run of the first conveyor, and the return run of the first conveyor lies above the return run of the second conveyor, the deck plate of the first conveyor terminating at a location above the conveying run of the second conveyor, to define an absent deck plate area, and continuing beyond the conveying run of the second conveyor.

Thus, in contrast to prior art side discharge proposals, the system in accordance with the invention requires the deck plate to be completely absent above an area of the conveying run of the second conveyor, i.e. for a distance approximating to the width of the second conveyor, thus removing any obstruction to coal flow onto the second conveyor, the system of the invention avoiding any attempt to support the drive chain(s) of the first conveyor, but simply relying firstly on the tension conventionally imposed on the first conveyor drive chain(s), of the first conveyor to maintain taut the chain(s) along the absent deck plate area above the second conveyor, until the chain(s) and flight bars engage the first conveyor deck plate beyond the second conveyor.If it is considered necessary e.g., on a single chain, centre strand conveyor, flight bar positional control maybe effected by a guideway located at one side of the first conveyor, at least along the absent deck plate area.

Although the first conveyor, could be of the twin outboard strand type, it is preferably of a centre strand type, having either a single chain or a pair of chains. Preferably, the return run of the first conveyor is open to the return run of the second conveyor. With the last mentioned arrangement, it is further preferred for the first conveyor to have a return end which is shrouded, so that any coal carried past the second conveyor firstly is confined, and secondly with the open return run of the first conveyor above the return run of the second conveyor, this coal is discharged into the second conveyor return run. The second conveyor is preferably provided with a return end which is at least partially shrouded. Partial shrouding, to leave a loading gap, may be desirable to permit the hand loading of coal, required to be cleared, into the conveyor system.A shrouded, or partially shrouded, return end of the second conveyor results in coal being passed around the second conveyor return end and hence into the conveying run of the second conveyor.

The invention will now be described in greater detail, by way of examples, with reference to the accompanying drawings, in which; Figure 1 is a plan view of a scraper chain conveyor system in accordance with the invention; Figure 2 is an end elevation of Figure 1 in the direction of arrow A; and Figure 3 is a side elevation of Figure 1 in the direction of arrow B.

In the drawings, a mine system in accordance with the first aspect of the invention comprises a mineral face 1, at least one end of which terminates at a roadway 2, with a mine floor being indicated at 3. A first armoured, scraper chain conveyor 4 is built up to desired length by securing together end-to-end, in articulated manner, a plurality of unit length line pans, only one line pan 5 being indicated, the line pan 5 being connected to a head frame 6 which defined a head end of the first conveyor 4. Each line pen 5 comprises a pair of spaced apart, parallel, sigma section sidewalls 7 interconnected by a deck plate 8 which separates an upper, conveying run 9 from a lower return run 10.The head frame 6 comprises, in the same manner as the line pans 5, a pair of spaced apart, parallel, sigma section sidewalls 11 interconnected by a deck plate 12, the sidewalls 11 and deck plate 12 being upwardly inclined, as can be seen from Figure 2, from the level of the line pan 5. The tail end of the first conveyor, which is for example some 200 yards distant from the head end, is not illustrated. The first conveyor 4 is of the twin centre strand type, the chains being indicated partially by round links 13, but principally by chain lines 14, the chains carrying a plurality of transversely extending flight bars 15 attached at longitudinally spaced apart locations.As best illustrated in Figure 1, the first conveyor 4 has a delivery end 16 comprising a sprocket ring 17 mounted on a sprocket barrel 18 rotatable about an axis 19 extending transversely of the first conveyor 4, the sprocket barrel 18 being mounted on a drivable shaft 20, with spaced apart ends of the shaft 20 being supported for rotation about axis 21 in bearing blocks 22 carried by spaced apart, parallel sidewalls 23 of the head frame 6, the sprocket ring 17 serving to drive the first conveyor 4 from a drive unit 24 (to be described in detail later), while the delivery end 16 is shrouded by the provision of a partially curved shroud plate 25. The conveyor 4 conveys coal in the direction of arrow C (Figure 1) and is adapted for side discharge of the coal onto a second scraper chain conveyor 26 (to be described in detail later).Side discharge is effected by a curved plough plate 27, supported from the sidewalls 23, so that the bulk of the coal on the conveyor 4 is ploughed onto the second conveyor 26, in the direction indicated by the curved arrows D in Figure 1.

Considering now the drive unit 24, this is located in the roadway 2 and comprises an electric motor 28, to drive a fluid coupling 29, to drive a speed reduction gear box 30, an output shaft of which drives a propeller shaft 31 connected to the barrel shaft 20. The drive unit 24, extends parallel to the longitudinal direction of the roadway 2 and to the second conveyor 26 which is also located in the roadway 2 and extends orthogonally, or generally so, with respect to the first conveyor 4. A drive unit for the second conveyor 26 is not illustrated. The second conveyor 26 also comprises a pair of spaced apart, parallel, sigma section sidewalls 32 interconnected by a deck plate 33 to separate an upper, conveying run 34 from a lower, return run 35.The second conveyor 26 is also of the twin centre strand type, the chains again being indicated partially by round links 36, but principally by chain lines 37 the chains carrying a plurality of transversely extending flight bars 38. The second conveyor 26 has a return end 37 incorporating a return sprocket barrel 40 rotatable about axis 41, the return end 39 being partially shrouded by a curved shroud plate 42, the partial shrouding producing a gap 43 into which any spilled coal may be loaded, by hand.

As best illustrated in Figure 1, adjacent ends of the first and second conveyors 4, 26 overlap one another, so that, as best seen in Figure 3, the conveying run 9 of the first conveyor 4 lies above the conveying run 34 of the second conveyor 26, which run 34 lies above a return run 10 of the first conveyor 4, which run 10 is open to, and lies above, a return run 35 of the second conveyor 26, so that the various runs of the conveyers 4 and 26 are interleaved.However, the deck plate 8 is of the first conveyor 4 terminated at an edge 44, with a downwardly inclined transition portion 45, at a location where the deck plate 8 lies above one sidewall 32 of the second conveyor 26, the deck plate 8 continuing at an edge 46 beyond the second conveyor 26 and specifically just beyond the other sidewall 32 of that conveyor, so that the deck plate edges 44 and 46 and spaced apart by a dimension 47 of what may be termed an absent deck plate area, the dimension 47 approximating to the width of the second conveyor 26.Also indicated in the drawings is a guideway 48 defined between upper and lower flanges 49, 50, the guideway 48 being intended to receive slidably an adjacent end of flight bars 15 of the first conveyor 4, for additional control of those flight bars with respect to their supporting chains, the guideway 48 extending at least over the width of the second conveyor 26.

Thus, coal, deflected or ploughed by the plough plate 27 falls through the absent deck plate area of the upper conveying run 9 and hence is discharged from the the first conveyor 4 onto the conveying run 34 of the second conveyor 26. Any small quantity of coal that may be carried over the absent deck plate area by the chains and flight bars is, because of the presence of the shroud plate 25, conveyed, by the flight bars 15, generally downwardly but through 180 , in the direction of arrows E into the return run 10 of the first conveyor 4. Because the return run 10 of the first conveyor 4 is open to the return run 35 of the second conveyor 26, this coal falls, as indicated by arrows F, into the return run 26. Because of the presence of the shroud plate 41, this coal is conveyed generally upwardly but through 180 , by the action of flight bars 38, in the direction of arrows G into the conveying run 34 of the second conveyor 26.

Claims (9)

1. A scraper chain conveyor system comprising a first scraper chain conveyor, and a second scraper chain conveyor extending orthogonally, or generally so, with respect to the first conveyor, both the first and the second conveyors incorporating at least one tensioned drive chain with a plurality of transversely extending flight bars attached thereto at longitudinally spaced apart locations, with adjacent ends of the first and second conveyors overlapping one another at a cross over junction and with the conveying and return runs of the first and second conveyors interleaved, so that the conveying run of the first conveyor lies above the conveying run of the second conveyor, the conveying run of the second conveyor lies above the return run of the first conveyor, and the return run of the first conveyor lies above the return run of the second covneyor, the deck plate of the first conveyor terminating at a location above the conveying run of the second conveyor to define an absent deck plate area and continuing beyond the conveying run of the second conveyor.

2. A system as claimed in Claim 1, wherein, a guideway for the flight bars of the first conveyor is located at one side of the first conveyor at least along the absent deck plate area.

3. A system as claimed in Claim 1 or Claim 2, wherein the first conveyor is of the twin outboard strand type.

4. A system as claimed in Claim 1 or Claim 2, wherein the first conveyor is of the single chain centre strand type.

5. A system as claimed in Claim 1 or Claim 2, wherein the first conveyor is of the twin chain centre strand type.

6. A system as claimed in any preceding Claim, wherein the return run of the first conveyor is open to the return run of the second conveyor.

7. A system as claimed in any preceding Claim, wherein the first conveyor has a delivery end which is shrouded.

8. A system as claimed in any preceding Claim, wherein the second conveyor has a return end which is at least partially shrouded.

9. A scraper chain conveyor system substantially as hereinbefore described with reference to the accompanying drawings.