GB2148834A - Side discharge conveyor frame - Google Patents

Abstract

A side discharge conveyor frame 1 for a twin outboard strand scraper chain conveyor with flight bars 7 at regular pitch, extending transversely of the chains 6 and connected thereto comprises spaced apart, parallel, elongate side walls 2 and an interconnecting deck plate 3 which separates an upper, conveying run from a lower, return run, a plough or discharge door 8 located non-orthogonally with respect to the side walls 2 across the upper conveying run, and means to elevate the mineral being conveyed along the conveying run above the normal chain line 6 adopted by the length of chain between two adjacent flight bars 7, whereby upon striking the plough or discharge door 8, the bulk of the material being conveyed is side discharged from a location above the normal chain line 6. The elevating means may be a resilient upwardly blistered deck plate, a spring-loaded hinged deck plate, a tapered roller, a flexible coil spring, or a continuously driven secondary belt. <IMAGE>

Description

SPECIFICATION Conveyor frame and conveyor incorporating such frame This invention relates to a conveyor frame to form part of an armoured, scraper chain conveyor, as used extensively in coal, potash etc. mining operations for example. The invention also includes a conveyor incorporating such a frame.

Conventional scraper chain conveyors comprise a plurality of line pans of unit length e.g. 5ft., secured together end-to-end in an articulated manner, to make up a conveyor of the desired length, each line pan comprising a pair of spaced apart, elongate side walls secured together by a deck plate which separates an upper, conveying run from a lower, return run. A head frame is provided at the head end of the conveyor and a tail frame is provided at the tail end of the conveyor, both frames incorporating inter alia drive and/or return sprocket barrels for the endless haulage chain(s) of the conveyor to which chain(s) at spaced intervals are attached transversely extending flight or scraper bars, with either the head frame sprocket barrel, or both the head frame and the tail frame sprockets barrels driven.These conveyors are of two basic types, with either twin outboard chains attached to the outer ends of the flight bars or with single or twin centre chains attached to a central portion of each flight bar.

A conventional configuration in underground longwall mining operations is to have the armoured conveyor extending along the mineral face, with the mineral discharged from this face conveyor on to what is known as a beam stage loader conveyor extending along a mine roadway usually located orthogonally with respect to the mineral face. With a twin outboard face conveyor, the head frame is elevated so that the mineral being conveyed is similarly elevated for "over the top" delivery on the the stage loader conveyor.

Such delivery from a face conveyor of say 6001600 tons/hr. capacity, has several disadvantages, such as the creation of dust, the degradation of the mineral involved and the frequent blockage or jamming at the delivery area from an inconsistency of material size e.g. relatively large lumps of mineral bridge the stage loader conveyor, and a requirement to turn the mineral through 90 at the delivery area. Furthermore, the face conveyor requires additional power to elevate the mineral along the head frame and over the drive barrel there of.

However, with centre strand conveyors, having either single or twin chains, the possibility exists of avoiding over the top discharge, and effecting side discharge. This arrangement has several advantages such as smoother mineral flow from the face conveyor to the stage loader conveyor, resulting in reduced dust creation, reduced mineral degradation, and a decrease in the power requirements of the face conveyor, as it is not necessary to elevate the mineral to any great extent.In detail, with the stage loader conveyor located beneath the face conveyor in the region of the side discharge area i.e. inwardly of at least the terminal end of the head frame, material discharge is effected firstly by a plough or discharge door (which may be curved or planar) located at an angle across the conveying run of the face conveyor, with clearance between the lower edge of the door and the deck plate to allow passage of the flight bars beneath the door, and secondly by the deck plate in the vicinity of the discharge area being angled downwardly, at both lateral sides of the conveyor, from a central land, which remains at deck plate height and along which land the chain(s) and/or a supporting, central shoe of each flight bar is adapted to slide, with major discharge being effected at one side of the face conveyor i.e. that towards which mineral is urged by the plough or door and with minor discharge e.g. of fines etc., being effected at the other side of the conveyor.

However the vast majority of conveyors in British coal mines are not of the centre strand type, but on the contrary are of the twin outboard type, which has the inherent disadvantage that side discharge mineral flow is impeded at both sides of the conveyor, but particularly at that side to which the major proportion of mineral is being ploughed, by the presence of the outboard chain strand. Also, with side discharge of a twin outboard face conveyor, there is a diminishing triangular area between the chain, flight bar, and discharge door in which mineral lumps become trapped, which eventually leads to bursting of the lumps, with attendant hazard to personnel in the vicinity, and/or chain(s), resulting in loss on mineral production until such time as the damage is repaired.

According to the present invention, there is provided a side discharge conveyor frame for a twin outboard strand scraper chain conveyor with flight bars, at regular pitch, extending transversly of the chains and being connected thereto, the frame comprising spaced apart, parallel, elongate side walls and an interconnecting desk plate which separates an upper, conveying run from a lower, return run, a plough or discharge door located nonorthogonally with respect to the side walls across the upper conveying run, and means to elevate the mineral being conveyed along the conveying run above the normal chain line adopted by the length of chain between two adjacent flight bars, whereby upon striking the plough or discharge door, the bulk of the material being conveyed is side discharged from a location above the normal chain line.

Thus, with a frame in accordance with the invention the mineral, pushed along the deck plate by the flight bars eventually reaches, and climbs the elevating means, to clear the obstruction normally presented by the chain line of a twin outboard strand conveyor, i.e. the chains are no longer in the discharge path, at least for the bulk of the material being discharged.

The invention also includes a scraper chain conveyor provided with a conveyor frame as defined above.

The elevating means may take various forms.

Thus in the first embodiment the elevating means is constituted by a resilient, upwardly blistered deck plate, which may be constituted by a plurality of flexible, convex single leaf springs located between the outboard chains, such that mineral is elevated by the springs, the chain line remaining below the mineral flow, thereby avoiding the presentation of any obstruction to discharge. As the flight bars climb the deck, the springs eventually and progressively deflect to allow the flight bars to clear individually the underside of the door.

In a second embodiment, the deck plate is rigid and the elevating means takes the form of an integral blister portion provided on the upper surface of the deck plate, with the blister portion returning to the deck plate part-way along the plough or door to define a gap between the deck plate and the lower edge of the door for the passage of the flight bars, so that with this embodiment the chain line varies with the position of the flight bar on the blister portion.

in a third embodiment, a portion of the deck plate between the outboard chains is hinged, and spring-loaded upwardly, so as to be capable of deflection downwardly to allow for passage of the flight bars beneath the lower edge of the door.

In a fourth embodiment, a tapered roller, rotatable about a transverse axis is provided, the roller serving to lift and roll mineral over the adjacent chain, the roller preferably being provided with a plurality of radial vanes, with roller rotation synchronised with the conveyor haulage speed, so that an approaching flight bar engages a gap between two adjacent vanes, and hence the adjacent chain does not deviate from its line. A portion of the deck plate is preferably angled downwardly from both sides of a central land, to aid discharge.

In a fifth embodiment, an inclined flexible coil spring forms an inclined roller under the lower end of a discharge door, thus rolling and lifting the mineral over the adjacent chain, with an approaching flight bar deforming and deflecting the spring, to enable the flight bar to pass under the door. The inclined spring may be provided at one end with a supporting coil spring, with again a portion of the deck plate being angled downwardly from both sides of a central land.

Finally, in a sixth embodiment the mineral elevating means takes the form of a continuously driven secondary belt or chain conveyor, acting as a rolling deck, provided to elevate the mineral over the chain line. Conveniently the belt may be made up of a series of ribs and interposed slots into which slots the flight bars are synchronised to engage, in which case larger lumps of mineral may bridge adjacent ribs.

The invention will now be described in greater detail, by way of examples, in the accompanying drawings, in which: Figure 1 is a side elevation of a first embodiment of conveyor frame in accordance with the invention; Figure 2 is a plan view of Figure 1; Figure 3 is a side elevation of a second embodiment of conveyor frame in accordance with the invention; Figure 4 is a plan view of Figure 3; Figure 5 is a side elevation of a third embodiment of conveyor frame in accordance with the invention; Figure 6 is a plan view of Figure 5; Figure 7 is a side elevation of a fourth embodiment of conveyor frame in accordance with the invention; Figure 8 is a plan view of Figure 7; Figure 9 is a side elevation of a fifth embodiment of conveyor frame in accordance with the invention; Figure 10 is a plan view of Figure 9;; Figure Ii is a side elavation of a sixth embodiment of conveyor frame in accordance with the invention; and Figure 12 is a plan view of Figure 11.

In all the figures, like components are accorded like reference numerals.

In the embodiment of Figures 1 and 2 is illustrated a conveyor frame 1 adapted to form one terminal end - in fact a head end - of an armoured, scraper chain conveyor, the latter being built up to the desired length e.g. 200 yards by securing together end-to-end, and in an articulated manner, a plurality of individual line pans of unit length e.g.

5ft. so that the other, non-illustrated end of the conveyor terminates in a tail frame.

The conveyor frame 1 comprises a pair of rigid, parallel and elongate side walls 2 spaced apart by an interconnecting deck plate 3 at a distance approximating to the width of the conveyor, the deck plate 3 separating an upper, conveying run from a lower, return run. The side walls 2 provide support means for a rotatable sprocket barrel 4 carrying a pair of spaced apart sprockets 5 for engagement respectively with a pair of endless, round link chains, the chain lines being indicated at 6, with flight bars 7 secured in the conventional manner, at regular pitch, transversely of the chains, the flight bars 7 being connected at each end to one of the chains. At the head frame, depending on the horse power requirements of the particular conveyor involved, the sprocket barrel 4 may be driven or non-driven.

As indicated previously, the conveyor frame 1 is intended for what is known as side discharge of the material being conveyed, and for this purpose a plough, or discharge door 8 is angled across the conveying run, as can be appreciated from Figure 2, thus, serving to deflect or plough the conveyed material from the conveyor and through approximately 90 onto a receiving conveyor (not shown), the plough 8 being rigidly supported from the frame 1 by any suitable means. An angled slot 9 is cut into the deck plate 3, the slot 9 being defined by a pair of angled faces 10 extending parallel or generally so, to the inclination of the plough 8 (as can be appreciated from Figure 2), by a pair of end faces 11 extending parallel to the side walls 2, and by a pair of transverse faces 12 interconnecting adjacent faces 10 and 11. Beneath the slot 9 is located a support plate 13, as indicated in Figure 1, with terminal ends 14 so as to define receiving ap ertures 16 for opposite ends of a plurality of individual, flexible, convex single leaf springs 17 located in side-to-side abutting relationship across the slot 9, the convexity of the springs 17 being such that central portions of the springs, in a nondeflected condition, lie above the deck plate 3, with the result that mineral being conveyed by the flight bars 7 is elevated by the springs 17 to an extent that the elevated mineral is above the chain line 6 at the discharge side of the frame 1, and thus that chain presents no obstruction to mineral discharge, as would be the case if no mineral elevation were effected.It is clearly necessary to permit a similarly elevated flight bar to pass beneath the plough 8, and deflection of the springs 17 to the position indicated in chain dotted line, accommodates this.

In the embodiment of Figures 3 and 4, the elevating means takes the form of an integral blister portion 3A of the deck plate 3, with the blister portion 3A returning to the deck plate part way along the plough 8, at an angled, transition portion 3B, to define a gap G between the deck plate 3 and the lower edge of the plough 8, so that flight bars 7 may pass beneath the plough 8.

In the embodiment of Figures 5 and 6, a portion 3C of the deck plate 3 between the outboard chain lines 6 is hinged at 18, and is spring-loaded upwardly, by a coil compression spring 19, so as to be capable of deflection downwardly upon a flight bar 7 arriving at the portion 3C, so as to allow for passage of the flight bars 7 beneath the lower edge of the door 8 and, in a non-deflected condition, to elevate the conveyed material above the chain line 6, particularly at the discharge side of the conveyor frame 1.

In the embodiment of Figures 7 and 8 there is provided a tapered roller 20, rotatable about a transverse axis 21, while the deck plate 3 is provided with inclined surfaces 3D extending downwardly from each side of a central land 3E at the level of the deck plate 3. The roller 20 serves to lift and roll mineral over the chain extending along chain line 6 at the discharge side of the conveyor frame 1. The roller 20 is provided with a plurality of radial vanes 22 and the rotational speed of the roller 20 is synchronised with the conveyor haulage speed, so that an approaching flight bar 7 engages a gap 23 between two adjacent vanes 22 and hence the chain at the discharge side of the conveyor frame 1 does not deviate from its chain line 6.

In the embodiment illustrated in Figures 9 and 10, an inclined, flexible coil spring 24 forms an inclined roller under the lower edge of the discharge door 8, thereby rolling and lifting mineral over the chain at the discharge side of the conveyor frame 1, with an approaching flight bar 7 deforming and deflecting the spring 24, to enable the flight bar to pass under the door 8. Preferably, the inclined spring 24 is provided at its upper end with a supporting coil spring 25, while again the deck plate 3 is downwardly angled at 3D from both sides of a central land 3E.

In the embodiment illustrated in Figures 11 and 12, the elevating means for the material being conveyed takes the form of a continuously driven, secondary, belt conveyor 26 acting as a rolling deck.

The belt of the conveyor 26 comprises a series of spaced apart ribs 27 and interposed slots 28, into which slots the flight bars 7 are synchronised to engage.

Claims (17)

1. A side discharge conveyor frame for a twin outboard strand scraper chain conveyor with flight bars, at regular pitch, extending transversly of the chains and being connected thereto, the frame comprising spaced apart, parallel, elongate side walls and an interconnecting desk plate which separates an upper, conveying run from a lower, return run, a plough or discharge door located nonorthogonally with respect to the side walls across the upper conveying run, and means to elevate the mineral being conveyed along the conveying run above the normal chain line adopted by the length of chain between two adjacent flight bars, whereby upon striking the plough or discharge door, the bulk of the material being conveyed is side discharged above the normal chain line.

2. A side discharge conveyor frame as claimed in Claim 1, wherein the elevating means is constituted by a resilient, upwardly blistered deck plate.

3. A side discharge conveyor frame as claimed in Claim 2, wherein the resilient, upwardly blistered deck plate is constituted by a plurality of flexible, convex single leaf springs located between the outboard chains.

4. A side discharge conveyor frame as claimed in Claim 2, wherein the deck plate is rigid and the elevating means takes the form of an integral blister portion provided on the upper surface of the deck plate, with the blister portion returning to the deck plate part-way along the plough or door to define a gap between the deck plate and the lower edge of the door for the passage of the flight bars.

5. A side discharge conveyor frame as claimed in Claim 2, wherein a portion of the deck plate between the outboard chains is hinged, and springloaded upwardly, so as to be capable of deflection downwardly to allow for passage of the flight bars beneath the lower edge of the door.

6. A side discharge conveyor frame as claimed in Claim 2, wherein a tapered roller, rotatable about a transverse axis is provided, the roller serving to lift and roll mineral over the adjacent chain, with roller rotation synchronised with the conveyor haulage speed.

7. A side discharge conveyor frame as claimed in Claim 6, wherein the roller is provided with a plurality of radial vanes, with the synchronisation ensuring that an approaching flight bar engages a gap between the two adjacent vanes, and hence the adjacent chain does not deviate from its line.

8. A side discharge conveyor frame as claimed in Claim 6 or Claim 7, wherein a portion of the deck plate is angled downwardly from both sides of a central land, to aid discharge.

9. A side discharge conveyor frame as claimed in Claim 2, wherein an inclined flexible coil spring forms an inclined roller under the lower end of a discharge door, thus rolling and lifting the mineral over the adjacent chain, with an approaching flight bar deforming and deflecting the spring, to enable the flight bar to pass under the door.

10. A side discharge conveyor frame as claimed in Claim 9, wherein the inclined spring is provided at one end with supporting coil spring, with again, a portion of the deck plate being angled downwardly from both sides of a central land.

11. A side discharge conveyor frame as claimed in Claim 2, wherein the mineral elevating means takes the form of a continuously driven secondary belt or chain conveyor, acting as a rolling deck, provided to elevate the mineral over the chain line.

12. A side discharge conveyor frame as claimed in Claim 11, wherein the belt is made up of a series of ribs and interposed slots into which slots the flight bars are synchronised to engage.

13. A scraper chain conveyor provided with a conveyor frame as defined in any preceding Claim.

14. A side discharge conveyor frame for a twin outboard strand scraper chain conveyor substantially as hereinbefore described with reference to Figures 1 and 2 of the accompanying drawings.

15. A side discharge conveyor frame for a twin outboard strand scraper chain conveyor substantially as hereinbefore described with reference to Figures 3 and 4 of the accompanying drawings.

16. A side discharge conveyor frame for a twin outboard strand scraper chain conveyor substantially as hereinbefore described with reference to Figures 7 and 8 of the accompanying drawings.

17. A side discharge conveyor frame for a twin outboard strand scraper chain conveyor substantially as herein before described with reference to Fr substantially as herein before described with reference to Figures 11 and 12 of the accompanying drawings.