GB2042028A

GB2042028A - An improvement in or relating to coal cutter drums

Info

Publication number: GB2042028A
Application number: GB8004444A
Authority: GB
Original assignee: Rands E D; Whinfrey A F
Current assignee: Rands E D; Whinfrey A F
Priority date: 1979-02-14
Filing date: 1980-02-11
Publication date: 1980-09-17

Abstract

A coal cutter drum is carried by a shaft, the drum being provided over a relatively narrow region at the end remote from the shaft with a plurality of cutter pick boxes (20) spaced apart around the periphery of the drum and being provided over the remainder of its width with pick boxes (20) spaced apart at a relatively greater peripheral spacing. <IMAGE>

Description

SPECIFICATION An improvement in or relating to coal cutter drums The invention relates to coal cutter drums, that is to say rotary devices, used in mining for operating upon the coal face by means of cutter picks. The cutter picks are usually removably mounted in pick boxes which are commonly mounted on helical wings projecting from a cylindrical body part. In use the drum is rotated and traversed along the coal seam so that the picks cut the coal.

The object of the invention is to provide an improved coal cutter drum which in use will produce "larger" coal than hitherto, that is to say coal in relatively large lumps.

According to the invention, there is provided a coal cutter drum which over a relatively narrow region at one end, that is to say at an end which in use will be remote from the coal cutting machine, has a plurality of cutter pick boxes spaced apart around the periphery of the drum and which over the remainder of its width has pick boxes spaced apart at a relatively greater peripheral spacing, the arrangement being such that as the drum rotates and traverses sideways along a coal seam there tends to be produced a relatively narrow steadily advancing slot behind and parallel with the coal'face and then a more intermittent removal of the coal remaining immediately adjacent the coal face.The relatively narrow region of the drum which has a plurality of coal cutter pick boxes spaced apart around the periphery of the drum may be in the region of one third of the total width of the drum or perhaps less. The pick boxes will preferably be mounted on helical wings projecting from a cylindrical body part and in this case the required difference in spacing of the pick boxes between the relatively narrow region of the drum and the remainder of the drum may be brought about by only a relatively small number of said wings extending over the full width of the body part, the remaining wings extending over only said relatively narrow region of the drum.

In order that the invention may be fully understood and readily carried into effect, the same will now be described, by way of exam ple only, with reference to the accompanying drawings, of which: Figure 1 is a diagrammatic view showing a rotary coal cutter drum embodying the invention in use in a coal seam, Figure 2 is a plan view of the drum, drawn to a somewhat larger scale than Fig. 1, Figure 3 is a detail view of a part of the drum which will be referred to, and Figure 4 is a perspective view of a coal cutter drum embodying the invention.

Referring now to Fig. 1, this illustrates the use of a rotary coal cutter drum 10 embodying the invention, the drum being presented to the coal face A with its axis substantially parallel with that part B of the face into which the drum is to be traversed. As shown, the drum is carried by a shaft 1 2 extending laterally from a power driven machine (not shown) and extends into the face a distance substantially equal to its full width. The drum is provided with a number of helical wings 14, which will be described presently, and these are disposed at such an angle to the coal face that much of the removed coal falling onto the drum is thrown off outwardly therefrom and.rearwardly therefrom as indicated by the arrows.

Referring now to Figs. 2 and 3, it will be seen that the wings 1 4 are constituted by a plurality of fabricated pick carrying elements 1 6 which are arranged substantially in parallel on a cylindrical body part 18, cutter pick boxes 20 are welded to the elements 1 6 and are disposed so that coal cutter picks 22 which are carried by the pick boxes are presented to the coal face at the required angles.

In the illustrated embodiment there are nine helical wings extending across the cylindrical surface of the body part 1 8. However, only three of these wings extend over the full width of the body part, the remaining wings extending over only a relatively narrow region at the end which in- use will be remote from the coal cutting machine, this relatively narrow region being approximately one third of the total width of the drum. The effect of this is that, with the cutter pick boxes substantially equally spaced apart along the wings, the drum has a relatively narrow region, at that end which in use will be remote from the coal cutting machine, which has a plurality of cutter pick boxes spaced apart around the periphery of the drum. Over the remainder of its width the drum has pick boxes spaced apart at a relatively greater peripheral spacing.

The arrangement is such that when the drum is in use as shown in Fig. 1, there tends to be produced a relatively narrow and steadily advancing slot behind and parallel with the coal face and then a more intermittent removal of the coal remaining immediately adjacent the coal face. This more intermittently removed coal will stand somewhat proud of the part B of the face by the time the more widely spaced picks come around to remove it, so that it is in the nature of a relatively weak wall of remaining coal. Consequently, it can be expected that it will be broken away in the form of relatively larger lumps than usual.

It can also be expected that there will be produced a significantly smaller quantity of dust and a fine coal.

Various modifications may be made without departing from the scope of the invention, particularly in the manner in which the wings 1 4 are formed. It will also be understood that by trial and experiment the optimum width of the relatively narrow region of the drum may be determined. Also, the number of the helical wings may be varied. For example, in Fig.

4 there is illustrated in perspective view a further embodiment of the invention, the dium in this case having eight wings only four of which extend across the full width of the drum. It may be found that for optimum performance a coal cutter drum embodying the invention needs to be driven with a different combination of rotary and forward traverse speeds.

Claims

1. A coal cutter drum which over a relatively narrow region at one end, that is to say at an end which in use will be remote from the coal cutting machine, has a plurality of cutter pick boxes spaced apart around the periphery of the drum and which over the remainder of its width has a pick boxes spaced apart at a relatively greater peripheral spacing, the arrangement being such that as the drum rotates and traverses sideways along a coal seam there tends to be produced a relatively narrow steadily advancing slot behind and parallel with the coal face and then a more intermittent removal of the coal remaining immediately adjacent the coal face.

2. A coal cutter drum according to claim 1, in which the relatively narrow region of the drum which has a plurality of coal cutter pick boxes spaced apart around the periphery of the drum is in the region of one third of the total width of the drum or less.

3. A coal cutter drum according to either one of the preceding claims, in which the pick boxes are mounted on helical wings projecting from a cylindrical body part the required difference in spacing of the pick boxes between the relatively narrow region of the drum and the remainder of the drum being brought about by only a relatively small number of said wings extending over the full width of the body part, the remaining wings extending over only said relatively narrow region of the drum.

4. A coal cutter drum constructed and arranged stubstantially as hereinbefore described with reference to and as illustrated by the accompanying drawings.