GB2110193A

GB2110193A - Storage apparatus for excavated materials

Info

Publication number: GB2110193A
Application number: GB08227524A
Authority: GB
Inventors: Joe Hill
Original assignee: HILL Ltd J AND R
Current assignee: HILL Ltd J AND R
Priority date: 1981-10-01
Filing date: 1982-09-27
Publication date: 1983-06-15
Also published as: GB2110193B

Abstract

A storage apparatus for excavated materials comprises a hopper 10 having a closeable outlet 14 and a rotatable 22 drum with one closed end and one open end communicating with the hopper at 20. The drum is provided with vanes 34 for progressing material therealong and when it is desired to store material therein it is rotated and the hopper outlet is closed. The drum may be discharged by re-opening the hopper outlet. <IMAGE>

Description

SPECIFICATION Storage apparatus The present invention relates to storage appar atus, especially but not exclusively storage appar atus for use in a conveyor system.

The invention is particularly suitable in coal-min ing or quarrying operations. Here mechanical cutter means are used to excavate minerals but the rate of excavation is never constant. The minerals excavated are transported from the face by a system of conveyors which have a fixed capacity. If the output from the cutter exceeds the maximum removal capacity of the conveyor system or for some reason part of the conveyor system has to be stopped in normal circumstances the cutter would have to be stopped or at least slowed down.

This is wasteful and in the past the problem has been overcome by incorporating a storage apparatus or bunker in the conveyor system. The mineral excavated by the cutter is fed to a hopper of the bunker and normally passes directly through this hopper to a discharge conveyor. If, however, the discharge conveyor cannot cope with the quantity of material supplied to the hopper at least some of this material is diverted to a storage means incorporated in the bunker.

Prior bunkers have been open containers with an intermittently moveable conveyor forming their base so that when material has to be stored it is diverted onto the conveyor base which is advanced to draw material into the bunker. This material can then be returned to the discharge conveyor, for example, when the cutter is not delivering material to the hopper, simply by reversing the direction of the conveyor base of the bunker.

Bunkers of this nature have a number of drawbacks, not the least of which is the fact that owing to the inconsistent delivery of material thereto the level of material in the bunker varies and since it is "end-fed" it is difficult to fill it completely. In addition, the conveyor base arrangement has drawbacks in that it is liable to clog and consequently needs frequent maintenance. Prior bunkers also occupy relatively large areas and in an underground operation such areas are not often available without expensive excavations being carried out.

It is an object of the present invention to obviate or mitigate these disadvantages.

According to the present invention there is provided a storage apparatus comprising a loading hopper, an opening in one side thereof leading to a rotatable closed storage member which is provided with internal projections which, on rotation of the member progress material therealong and a closeable outlet in the hopper.

Preferably the apparatus includes means to cause a reversal of the direction of rotation of the member when it is approximately half full of material.

Preferably the member is a cylindrical drum and the internal projections therein may be a helical vane. Alternatively two parallel helical vanes are provided. The amount the projection extends from the inner periphery of the member is preferably less than the radius thereof.

Preferably the cylindrical member is supported by a plurality of trunnions. At least some of the trunnions may be driven or drive means may be incorporated at an end of the cylindrical member.

In a modified arrangement a hopper may be provided at each end of the rotatable member, in which case each end of the rotatable member is provided with a closure.

Means may be provided within the member for detecting when it becomes half full, these detecting means being connected to the control for the motor such that the direction of rotation of the member can be automatically reversed when the half full condition is detected.

Further according to the present invention there is provided a method of operating a storage apparatus of the type defined in the preceding seven paragraphs, comprising closing the hopper outlet, supplying material to the hopper, and rotating the rotatable member to draw material into the hopper and when it is desired to discharge material from the apparatus opening said outlet.

Preferably, at all times, the direction of rotation of the rotatable member is that which would normally cause the helical vanes to discharge material therefrom.

Further according to the present invention there is provided a method of filling a storage apparatus of the type defined in the said preceding seven paragraphs, the method comprising supplying material to the hopper such that it passes through said opening into the rotatable member, rotating the member in a first direction which causes said material to be drawn into the member, continuing said rotation until the member is substantially half full of material and thereafter reversing the direction of rotation while still supplying material to the hopper so that the member is filled beyond half full.

Further according to the present invention there is provided a method for emptying a storage apparatus of the type defined in the said preceding seven paragraphs when it is more than half full comprising initially rotating the member in a direction which would normally cause material to be progressed into the member until the member is half full and then reversing the direction of rotation to that which would normally progress material out of the member until it is empty.

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawing which shows diagrammatically a storage apparatus or bunker arranged in a conveyor system.

The bunker includes a hopper 10 into which a first conveyor 12 conveying excavated material, for example from a coalface, discharges. The hopper 10 has a first outlet 14 closable by a door 16. When said door is open material delivered to the hopper by the conveyor 12 falls through the outlet 14 on to a discharge conveyor 18. The hopper is provided also with a further circular opening 20 in its side opposite from the outlet 14, the opening 20 leading into a cylinder 22 which is mounted for rotation on a series of trunnions 24. The cylinder has an end closure 26 at its end remote from the opening 20 and a drive wheel 28 is mounted on this plate, the wheel 28 being driven by a motor 30 through a gear box 32.

A helical vane 34 is fixed to the internal periphery of the cylinder 22, the start of the vane being spaced from the opening 20 in the longitudinal direction of the cylinder and the vane terminating at the end closure 26. The vane 34 is of constant height, this height being less than the radius of the cylinder so that when viewed along the longitudinal axis of the cylinder there is a relatively unobstructive space in the central region.

When, in operation, it is desired to accumulate a supply of mineral in the cylinder the door 16 is closed so that material from the hopper spills through the opening 20 into the cylinder 22. The motor 30 is then started such that it rotates the cylinder in such a direction that the vane 34 moves material falling into the cylinder towards its closed end 26 in the manner of a screw. It is found that when sufficient material has been drawn in to half fill the cylinder it will admit no further material. If, however, the direction of rotation of the cylinder is reversed and the supply of material is continued so that material continues to pass through the opening 20 then surprisingly material continues to be drawn into the cylinder rather than being discharged therefrom as the direction of rotation of the helical vane 34 would suggest.Thus, rotation is continued in this direction while material is still supplied to the hopper and this can continue until the cylinder is completely filled.

To discharge material from the filled cylinder the door 16 is open such that material can fall from the hopper on to the conveyor 18 and the motor is actuated such that it rotates the cylinder in a direction which would normally cause material to be withdrawn from the cylinder that is the direction in which it was rotated to fill the second half of the cylinder. This results in a discharge of material from the cylinder into the hopper and discharge continues, without any change in the direction of rotation, until the cylinder is emptied.

It would appear that in a filling mode when the cylinder is half filled material which cannot be further progressed along the cylinder by the vane falls over the top of the vane. When the direction of rotation is reversed, the "rear" face of the vane acts on the material to convey it towards the end closure plate 26.

Various modifications can be made without departing from the scope of the invention, for example the helical vane 34 need not be continuous and could comprise a series of sections or alternatively a series of plate-like vanes projecting inwardly from the internal periphery of the cylinder. The cylinder need not be supported and driven in the manner described but could, for example, be driven by providing a drive means to one or more of the wheels of the trunnions. This would mean that the end of the cylinder could be free so that less space, in the long.tudinal direction of the bunker would be required. It could also mean that an additional similar hopper could be provided at the end of the bunker remote from the hopper 10 so that the bunker could be used as a storage apparatus for two conveyor systems.In this case it would be necessary to supply closures for the openings 20 in the hoppers to provide an end closure for the cylinder at its end opposite to the operational hopper. It will be realised that the drum need not be cylindrical but could be frusto-conical for example.

With certain excavated materials having a moisture content there may be a tendancy for the material to adhere to the drum interior or to the vanes. This problem may be obviated or mitigated by coating the said interior and vales with a non-stick material, for example a plastics material or a vulcanised rubber.

In another modification detecting means are located in the cylinder to sense when it is half full and to signal control means which automatically cause a reversal in the direction of rotation of the cylinder.

As a result of certain discoveries made during an experimental operation of the apparatus of the present invention there is a possibility that it can be put to uses other than simply for storage purposes.

For example after the drum has been filled it has been found that the material therein is graded in size to a substantial extent when it is discharged, smaller sized material tending to be discharged before larger sized material.

A further use of the drum which can be incorporated with a storage operation but need not be so combined is the washing of material. This can be achieved by supplying water to the rotatable member in any suitable way. Drain means can be provided for removing spent wash water.

If two or more different materials are fed to the cylinder they are blended together.

In a further modification two spaced parallel helical vanes are employed, the pitch of the vanes being equal to one and a half times the diameter of the cylinder. With this modified apparatus it has been found.that it is necessary to rotate the cylinder in one direction only for all filling and emptying operations. This direction is that which would normally cause the vanes to progress material out of the cylinder. In practice, so long as material is fed to the hopper and the outlet therefrom is closed, rotation of the cylinder causes material to be taken in. To discharge the cylinder it is necessary only to open said outlef.

Claims

1. A storage apparatus comprising a loading hopper, an opening in one side thereof leading to a rotatable closed storage member which is provided with internal projections which, on rotation of the member progress material therealong and a closeable outlet in the hopper.

2. Storage apparatus as claimed in claim 1, in which the member is a cylindrical drum.

3. Storage apparatus as claimed in claim 1 or claim 2, in which the internal projections therein are formed by a helical vane.

4. Storage apparatus as claimed in claim 1 or claim 2, in which two parallel helical vanes are provided.

5. Storage apparatus as claimed in any one of the preceding claims, in which the amount the projection extends from the inner periphery of the member is less than the radius thereof.

6. Storage apparatus as claimed in any one of the preceding claims, in which the cylindrical member is supported by a plurality of trunnions.

7. Storage apparatus as claimed in claim 6, in which at least some of the trunnions are driven.

8. Storage apparatus as claimed in any one of the preceding claims, in which drive means are incorporated at an end of the storage member.

9. Storage apparatus as claimed in any one of the preceding claims, including means to cause a reversal of the direction of rotation of the member when it is approximately half full of material.

10. Storage apparatus as claimed in any one of the preceding claims, in which a further hopper is provided at the end of the storage member opposite to the said hopper, a closure member being provided at each end of the storage member.

11. A storage apparatus as claimed in any one of the preceding claims, in which means are provided within the storage member for detecting when it becomes half full, these detecting means being connected to the control for the motor such that the direction of rotation of the member can be automatically reversed when the half full condition is detected.

12. A method of operating a storage apparatus as claimed in any one of the preceding claims comprising closing the hopper outlet, supplying material to the hopper, and rotating the rotatable member to draw material into the hopper and when it is desired to discharge material from the apparatus opening said outlet.

13. A method as claimed in claim 12, in which at all times, the direction of rotation of the rotatable member is that which would normally cause the helical vanes to discharge material therefrom.

14. A method of filling a storage apparatus of the type defined in any one of claims 1 to 11, comprising supplying material to the hopper such that it passes through said opening into the rotatable member, rotating the member in a first direction which causes said material to be drawn into the member, continuing said rotation until the member is substantially half full of material and thereafter reversing the direction of rotation while still supplying material to the hopper so that the member is filled beyond half full.

15. A method for emptying a storage apparatus of the type defined in any one of claims 1 to 11.

16. Storage apparatus substantially as hereinbefore described with reference to the accompanying drawing.

17. Method of operating storage apparatus substantially as hereinbefore described with reference to the accompanying drawing.

18. Any novel subject matter or combination including novel subject matter herein disclosed, whether or not within the scope of or relating to the same invention as any of the preceding claims.