GB2144700A - Drive frame and conveyor system incorporating same - Google Patents

Abstract

A drive frame (1) for driving simultaneously two adjacent and overlying ends (8, 12) of two armoured, scraper chain conveyors (3 and 4), comprises drive means incorporating firstly two spaced-apart, parallel output shafts (26, 27) rotatable in the same direction and adapted, in use, to make driving engagement with a drive shaft (11, 16) of each conveyor (3, 4), and secondly a drive unit comprising an electric motor (17), with a transmission (19,18) from the motor (17) to the drive means. The invention also includes a conveyor system comprising two armoured, scraper chain conveyors 3, 4 incorporating a drive frame (1) as defined above. <IMAGE>

Description

SPECIFICATION Drive frame and conveyor system incorporating same This invention relates to a drive frame for an armoured scraper chain conveyor, and to a conveyor system incorporating such a drive frame.

Armoured, scraper chain conveyors are used extensively in mineral mining operations, particular lyforthe longwall mining of coal, the conveyor being built up from a plurality of line pans e.g. of 5 ft.

length, secured together end-to-end to form a conveyor of the desired length, with one or more mineral winning machines e.g. of the shearer type or plough type, mounted on and/or guided by, the conveyor during their passage to and fro along the mineral face, and with a roadway located at one, or more usually both, end(s) of the face.

Necessarily, mineral faces vary in length, as does the size of chain(s) used for the conveyor. Thus depending upon the conveyor length, various sizes for the round links ofthe chain, such as 18, 19,22,26, and 34 mm, are available, while the number of drive units is again variable, each drive unit conventionally comprising either an electric motor, a fluid coupling, and a gearbox or a two speed electric motor and flexible couplings, and one or both ends of the conveyor may be provided with one or two drive units.It follows that with longer conveyors, larger drive horsepowers are required, but to avoid a large range of chain sizes and motor horsepowers being in use, and in order to provide some degree of standardisation, it has been proposed to provide a mid-face drive unit, whereby a single conveyor is replaced by a conveyor system incorporating two conveyors each approximating in length to half the length of the face, with adjacent ends of the two conveyors overlying one another, so that conveyed material may be discharged from the upper conveyor onto the lower conveyor.Whilst this arrangement allows the more commonly used 18, 19, and 22mm chain sizes to be employed, together with electric motors of the more commonly used horsepowers, the necessary overlapping, in the limited confines of a longwall face, requires a dinting operation on the mine floor to accommodate the end of the lower conveyor. Apart from the need to effect dinting, the very presence of a dint could mean that non-standard mine roof supports (compared with those provided along the remainder of the face) are required for the dint area and furthermore frequently leads to strata control problems.In detail, this known mid-face drive unit arrangement is to provide two individual drive units extending, at the goaf side of the conveyor, in opposite directions from one another, with one drive unit driving a tail end sprocket barrel (conventionally mounted co-axially on a drive shaft) of one of the "half" conveyors, and with the other drive unit driving a head end sprocket barrel of the other of the "half" conveyors. Hence this known arrangement of mid-face drive unit requires two electric motors, two fluid couplings and two gearboxes, as well as dint dimensions to accommodate these components.

According to a first aspect of the present invention there is provided a drive frame for driving simul taneouslytwo adjacent and overlying ends of two armoured, scraper chain conveyors, the drive frame comprising drive means incorporating firstly two spaced-apart, parallel output shafts rotatable in the same direction and adapted, in use, to make driving engagement with a drive shaft of each conveyor, and secondly a drive unit comprising an electric motor, with a transmission from the motor to the drive means.

According to a second aspect of the present invention there is provided a conveyor system comprising two armoured, scraper chain conveyors, adjacent ends ofthe conveyors overlying one another and each end comprising a sprocket barrel to be engaged by endless drive chain(s) of the associated conveyor, with both sprocket barrels rotatable about spaced-apart parallel axes and a drive frame as defined above, with the two output shafts thereof in driving relationship with a drive shaft of each sprocket barrel.

Thus, in contrast with the prior art proposal for a mid-face drive arrangsment, the present invention in its first and second aspects, provides a single drive unit common to the adjacent drive sprocket barrels of both conveyors, and consequently avoids the duplication of the prior art proposal of drive motors etc. Furthermore, because of the avoidance of duplication, the space required for a mid-face drive unit employing a drive frame in accordance with the invention is correspondingly reduced, as is consequently the time and energy required to effect dinting. Furthermore, the resulting smaller dint area minimises strata control problems.

The transmission of the drive unit may comprise either a fluid coupling and a speed reduction gearbox, or a two speed motor and flexible couplings, and in either case an output shaft of the gearbox would be drivably connected to the drive means.

Preferably, the latter comprises a drive pinion, rotatable about an axis parallel to that of the first and second drive shafts and sprocket barrels, the drive pinion being in mesh with driven pinions of both the first and second drive shafts.

The conveyors may be of the single or twin strand types. With twin strand conveyors, these may be inboard, centre strands or they may be outboard strands.

The invention will now be described in greater detail, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side elevation, looking from the goaf side of a drive frame and conveyor system in accordance with the invention; and Figure 2 is a plan view of Figure 1.

In the drawings are illustrated a drive frame 1 in accordance with the first aspect of the invention, and a conveyor system 2 in accordance with the second aspect of the invention. The conveyor system 2 comprises one armoured, scraper chain conveyor 3, illustrated to the lefthand side of Figures 1 and 2, and another armoured, scraper chain conveyor 4 illustrated to the righthand side of Figures 1 and 2. Both conveyors 3 and 4 are made up to their desired lengths by a plurality of line pans 5 secured together end-to-end in a conventional articulated manner, the pans 5 being illustrated as carrying individual rack bars 6 for use by a rack and pinion haulage system (not shown) of an associated mining machine (not shown).The conveyors 3 and 4 are seated on a mine floor 7, the conveyor 3 having a tail end (not shown) located for instance some hundred yards distant from its head end 8 which incorporates a frame which, in respect of the conveyor 3 constitutes a head frame and in respect of conveyor 4 consitutues a tail frame. The frame 9 rotatably houses a drive sprocket barrel 10 mounted on a drive shaft 11, over which sprocket barrel material conveyed by the conveyor 3 is discharged onto the conveyor 4, the head end of the conveyor 4 not being illustrated for, as with the tail end of conveyor 3, the head end of the conveyor 4 is located some hundred yards distant, a tail end 12 of the conveyor 4 underlying the head end 8 of the conveyor 3, or conversely the head end 8 overlying the tail end 12, so that the latter may receive, with minimum spillage, the material being discharged by the conveyor 3.Because of the need to overlie the adjacent ends 8 and 12 of the conveyors 3 and 4, a dint 13 is formed in the mine floor 7 over a distance D sufficient to accommodate not only the drive frame 1 in accordance with the first aspect of the invention, but also downwardly directed line pans 5A of the conveyor 4, which pans produce a gradual fall in the level of the conveyor 4 into the dint 13, until a tail end sprocket barrel 14, also rotatably supported in frame 9, and mounted on a drive shaft 16 is reached.

The drive frame 1 in accordance with the first aspect of the invention comprises an electric motor 17, to drive a speed reduction gearbox 18 via an interposed fluid coupling 19, the gearbox having a drive pinion 20 rotatable about an axis 21, the pinion 20 being in permanent driving engagement with a first, upper, driven pinion 22 rotatable about an axis 23 which is co-axial with the axis of rotation of the sprocket barrel 10 of the head end 8 of the conveyor 3, and also in engagement with a second, lower driven pinion 24, rotatable about the axis 25 parallel to the axis 23, the axis 25 being co-axial with the axis of rotation of the sprocket barrel 14 of the tail end 12 of the conveyor 4. An output shaft 26, also rotatable about the axis 23, is drivably connected to the pinion 22, while an output shaft 27, rotatable about the axis 25, is drivably connected to the pinion 24, both output shafts 26 and 27 being rotatable in the same direction, as consequently are their associated sprocket barrels 10 and 14, respectively. Connection of an output shaft 26,27 to drive shaft 16 respectively may be by any convenient means, e.g. a splined arrangement or an interposed coupling.

Claims (12)

1. A drive frame for driving simultaneously two adjacent and overlying ends of two armoured, scraper chain conveyors, the drive frame comprising drive means incorporating firstly two spaced-apart, parallel output shafts rotatable in the same direction and adapted, in use, to make driving engagement with a drive shaft of each conveyor, and secondly a drive unit comprising an electric motor, with a transmission from the motor to the drive means.

2. A drive frame as claimed in Claim 1, wherein the transmission of the drive unit comprises a fluid coupling and a speed reduction gearbox.

3. A drive frame as claimed in Claim 1, wherein the transmission of the drive unit comprises a twospeed electric motor and flexible couplings.

4. A drive frame as claimed in any preceding Claim, wherein the drive means comprises a drive pinion, rotatable about an axis parallel to that of the first and second drive shafts.

5. A conveyor system comprising two armoured, scraper chain conveyors, adjacent ends of the conveyors overlying one another and each end comprising a sprocket barrel to be engaged by endless drive chain(s) of the associated conveyor, with both sprocket barrels rotatable about spaced-apart parallel axes and a drive frame as defined in Claim 1 with the two output shafts thereof in driving relationship with a drive shaft of each sprocket barrel.

6. A conveyor system as claimed in Claim 5, wherein the drive means comprises a drive pinion, rotatable about an axis parallel to that of the first and second drive shafts and sprocket barrels, the drive pinion being in mesh with driven pinions of both the first and second drive shafts.

7. A conveyor system as claimed in Claim 6, wherein the conveyors are of the single strand type.

8. A conveyor system as claimed in Claim 6, wherein the conveyors are of the twin strand type.

9. A conveyor system as claimed in Claim 8, wherein the strands are inboard, centre strands.

10. A conveyor system as claimed in Claim 8, wherein the strands are outboard strands.

11. A drive frame substantially as hereinbefore described with reference to the accompanying drawings.

12. A conveyor system substantially as hereinbefore described with reference to the accompanying drawings.