GB2148143A - Apparatus for breaking lump material on a conveyor belt - Google Patents

Abstract

A lump breaker in a mine is constituted by a reciprocating chisel (10) which is mounted on a rotatable arm (6) so that it can be swung over a conveyor (1) to break large rock lumps (16). The arm (6) has a linkage (7) allowing the chisel (10) to be raised or lowered over the conveyor (1). <IMAGE>

Description

SPECIFICATION Apparatus for breaking lump material on a conveyor belt This invention relates to apparatus for breaking lumps of material on a conveyor belt and is particularly designed for dealing with lumps of hard material such as rock coming out of a mine or quarry on a travelling conveyor, usually known as an armoured face conveyor. The invention finds one specialised application, but not exclusive application, in coal mining.

In modern mining technology coal is mined on the longwall system where a conveyor is arranged parallel to a face being cut by a moving mining machine such as a shearer, moving along the conveyor to cut coal from the face. Material cut from the face is loaded onto the conveyor by the machine and carried away from the face onto other conveyors through means such as a stage loader.

A longwall face is typically 250 ms in length and a cutting machine travels to and fro along this face. In coal mining in order to maximisethe productivity of the mine the depth of the cut in the seam is carefully controlled so as to extract a maximum amount of coal and to leave the minimum necessary for roof support or floor support purposes.

Depending on the nature of the coal or the material being mined, large lumps often break off the face and fall onto the conveyor. Occasionally, if there is a weak or irregular roof, flamper from the roof, in the form of lumps of rock, fall onto the conveyor and have to be transported away.

There is clearly a physical limit to the size of material which can be conveyed and, although most conveyors are able to deal with large lumps, problems arise when these lumps are of abnormal size or when they have to be transferred from one conveyor to another or into tubs or taken up supply shafts.

One way of dealing with the problems of large lumps is to have colliers standing by with hammers to break the lumps manually. This is very wasteful of manpower and can be dangerous since if the flamper material is hard the hammer may well bounce off the rock. This can cause problems to the collier through jarring and can be ineffective as a breaking operation.

In certain longwall operations a crusher is incorporated on the conveyor where a rotary drum with picks breaks all large pieces of material coming along the conveyor and passes it all out at below a maximum size. Unfortunately, this type of crusher is expensive and the picks need constant replacement.

Furthermore, the presence of a crusher does limit the access to the face so that operators are unable easily to get onto the face to carry out repair or maintenance work on the equipment.

It is an object of the present invention to provide alternative apparatus for breaking lumps on a conveyor which is effective and which does not impede access to the face.

According to the present invention apparatus for breaking lumps of material on a conveyor comprises a conveyor and a reciprocating impact mechanism situated adjacent to the conveyor and supply means for the impact mechanism, the impact mechanism includes a base on which is rotatably mounted a head mechanism, the head mechanism having a reciprocatable impacting member arranged to be positioned over the conveyor to impact any matter above a set minimum size passing thereon in order to break the matter, and operating means arranged to raise and lower the set impacting member towards and away from the conveyor.

The apparatus is preferably hydraulically operated and the supply means is thus a source of hydraulic power. The source may be mounted on a bridge over an adjacent conveyor in order to minimise the obstructions in a mine roadway.

The impacting member may be mounted on an articulated linkage and may be raised and lowered by hydraulic means.

The impact member itself is preferably provided with a chisel bit which may be flat or pointed and which may have a hardened tip.

In order that the invention may be readily understood an example of the apparatus in accordance therewith will now be described with reference to the three accompanying drawings. In the drawings Figure 1 shows the positioning of the apparatus at a transfer stage on a coal mine conveyor. Figure 2 shows the apparatus of Figure 1 from a reverse view and Figure 3 in detail the impacting mechanism positioned over the conveyor.

Referring now to the drawings, the apparatus is located in a coal mine operating on a longwall face system and a coal mining machine (not shown) travels along a conveyor 1 of which only one end is shown in the drawings. The conveyor at its end is connected at a transfer point 2 to a stage loader 3 which allows material mined and travelling on the conveyor 1 to be carried over and to fall onto the stage loader 3 in the roadway of the mine in order to be able to travel out of the mine.

Adjacent the transfer point 2 and on the goaf side of it is positioned an impacting machine 4. This comprises a pedestal 5 having a rotary arm 6 pivotally mounted on its top. The arm 6 is comprised of a linkage 7 which is hydraulically operated through a piston 8 in order to enable the linkage 7 to be raised from the position shown in Figure 3 to that shown in Figure 1.

A hydraulic impactor 9 having a chisel reciprocating element 10 is pivotally connected at 11 to the linkage 7.

A hydraulic power pack 12 is positioned on a bridge 13 on top of the stage loader 3 and supplies power via hydraulic hoses 14 with the apparatus 4.

The position of the hydraulic unit 12 is as close as possible to the impactor 4 in order to minimise the length of the hose run 14. It will be seen particularly from Figure 2 that the hose run is carried in a member 15 over the transfer point 2 and conveyor 1.

The mining machine in normal operation mines coal of an average size which is suitable for travelling out of the mine along the conveyor 1 without any need for breaking. However, occasionally a large piece of coal from a roof fall of rock may result in large pieces such as those shown at 16 in Figure 3 falling onto the conveyors In order that these pieces may pass from the transfer point 2 onto the loader 3 the machine 4 is swung from its position as shown in Figure 2 where it is along side the conveyor to that shown in Figure 3 where the impactor 9 is over the conveyor 1. By operation of the hydraulic cylinder and piston 8 the linkage 7 can be lowered from an extreme position as shown in Figure 1 to a position as shown in Figure 3. When the impactor chisel 10 meets the rock on conveyor 1 it is operated and reciprocates to break the rock. It can be swung to a suitable position depending on the size and location of the lumps of rock 16.

The rock is broken until it is split into a sufficiently small size to pass readily from the transfer point 2 onto the stage loader 3 and to be able to pass under the bridge 13 holding the hydraulic unit 12.

If an exceptionally large piece of rock is presented the linkage can be raised to deal with this.

If access is needed for maintenance purposes of the face then the arm 6 can be swung on the pedestal 5 to the position as shown in Figure 2 so that no impediment is presented in operators getting onto the conveyor and along the face.

The invention enables an effective means of breaking large lumps of material to be readily available when needed but does not require it to be in constant operation when not needed.

Claims (7)

1. Apparatus.for breaking lumps of material in a conveyor comprises a conveyor and a reciprocating impact mechanism situated adjacent to the conveyor and supply means for the impact mechanism, the impact mechanism including a base on which is rotatably mounted a head mechanism, the head mechanism having a reciprocatable impacting member arranged to be positioned over the conveyor to impact any matter above a set minimum size passing thereon in order to break the matter, and operating means arranged to raise and lower the set impacting member towards and away from the conveyor.

2. Apparatus as claimed in Claim 1 in which the impact mechanism is hydraulically operated.

3. Apparatus as claimed in Claims 1 or 2 in which the supply means is a source of hydraulic power.

4. Apparatus as claimed in any preceding claim, in which the supply means is mounted on the, or an adjacent, conveyor.

5. Apparatus as claimed in any preceding claim in which the impacting member is mounted on an articulate linkage and is raised and lowered by hydraulic means.

6. Apparatus as claimed in any preceding claim in which the impacting member has a chisel bit.

7. Apparatus substantially as hereinbefore described with reference to the accompanying drawings.