WO2000078646A1

WO2000078646A1 - A guide arrangement

Info

Publication number: WO2000078646A1
Application number: PCT/GB2000/002089
Authority: WO
Inventors: Christopher Harper
Original assignee: Harper, Julia, M.
Priority date: 1999-06-17
Filing date: 2000-06-01
Publication date: 2000-12-28
Also published as: GB9914096D0; AU5091200A

Abstract

A guide arrangement for use with an endless conveyor (1) to prevent material from spilling from the conveyor, in which the guide arrangement comprises: a sealing skirt (13) which is arranged to engage against the conveyor (1) to form a seal therewith; and a restraining means (9, 10) adapted to maintain the sealing skirt (13) in contact with the conveyor; characterised in that the sealing skirt (13) is engageable with the conveyor (1) and is arranged to move in the same direction as the conveyor, thereby to minimise friction therebetween.

Description

A GUIDE ARRANGEMENT

The present invention relates to a guide arrangement for use with an endless conveyor to prevent material spilling from the conveyor, the guide arrangement comprising a sealing skirt which forms a seal with the conveyor and which is adapted to move with the conveyor.

If material spills from a moving conveyor belt it can often block the conveyor rollers and stop them from turning. This leads to one side of the blocked conveyor roller being worn away which in turn causes considerable damage to the underside of the conveyor belt.

Spillage has also been known to cause fires due to heat generated between the moving conveyor belt and an object trapped close to the belt .

For the above reasons it is necessary to spend time cleaning conveyor belts and rollers. However, many serious and even fatal accidents have occurred when cleaners have removed conveyor belt guards for cleaning purposes.

Guide walls which maintain material on the conveyor belt and stop it from spilling over the edges are known. Such guide walls can be used along the entire length of a conveyor belt. More typically they are used close to the receiving end of the conveyor belt to guide material as it is loaded on to the belt.

Known guide walls typically comprise fixed guide plates, one running along each edge of the conveyor belt. These guide plates often include rubber skirts which extend from the bottom of the guide walls and press against the moving conveyor belt so forming seals between the skirting and conveyor belt. These seals prevent the spillage of material from the edges of the belt.

However, because the conveyor belt moves with respect to the (fixed) rubber skirts both the rubber skirts and the conveyor belt become worn. Eventually a gap develops between the skirts and the conveyor belt allowing spillage of material.

Accordingly, the present invention provides a guide arrangement for use with an endless conveyor to prevent material from spilling from the conveyor, the guide arrangement comprising: a sealing skirt which is arranged to engagae against the conveyor to form a seal therewith; and, a restraining means adapted to maintain the sealing skirt in contact with the conveyor; characterised m that: the sealing skirt is engageable with the conveyor and is arranged to move m the same direction as the conveyor.

The guide arrangement according to the invention has the advantage that as the sealing skirt can move with the endless conveyor the friction between the sealing skirt and conveyor is reduced. This increases the life of both the sealing skirt and the conveyor (belt) . It also reduces the risk of fire from matter trapped between the sealing skirt and the conveyor belt.

Preferably, the guide wall further comprises a guide plate remote from the conveyor belt, the guide plate being adapted to constrain the motion of the sealing skirt. The guide plate can be substantially U shaped in cross section and can comprise a base and inner and outer side walls, the inner and outer side walls defining a mouth which opens towards the conveyor belt; the sealing skirt being constrained between the inner and outer walls.

The guide plate separates the moving sealing skirt from the surroundings, so protecting people standing close to the conveyor belt from accidental injury.

Preferably the restraining means comprises at least two return pulleys and the sealing skirt comprises an endless loop extending therebetween.

The sealing skirt can be arranged such that when the conveyor belt moves the sealing skirt moves around the guide pulleys due to the friction between the sealing skirt and the conveyor belt. This provides a simple method of ensuring that the sealing skirt moves along with the conveyor belt, so reducing friction between sealing skirt and conveyor belt.

At least one of the return pulleys can be connected to an external rotation means for rotating the return pulley, the return pulley m turn rotating the sealing skirt .

The present invention will now be described by way of example only, and not m any limitative sense, m which:

Figure 1 shows a conveyor belt and two known guide walls in end view;

Figure 2 shows a conveyor belt and first and second guide walls from above. The first and second guide walls are embodiments of the invention;

Figure 3 shows the conveyor belt and first guide wall of figure 2 in side view; and,

Figure 4 shows the conveyor belt and first and second guide walls of figure 2 m end view.

Shown in figure 1 , m end view, is a known arrangement of a conveyor belt 1 carrying material 2. The direction of travel of the conveyor belt 1 is normal to the plane of the page. Located on each side of the conveyor belt 1 are fixed metal guide walls 3, 4 which prevent the material from spilling from the moving conveyor belt 1. The conveyor belt 1 moves with respect to the guide walls 3, 4.

As can be seen, there is a small gap between each of the guide walls 3, 4 and the conveyor belt 1. This is because the metal guide walls 3, 4 would rapidly damage the upper surface of the conveyor belt 1. Extending from the lower edge of each of the guide walls 3, 4 are flexible rubber skirts 5, 6. Each of these skirts 5, 6 abuts against the conveyor belt 1 so forming a seal which prevents material 2 from spilling from between the guide walls 3, 4 and the conveyor belt 1.

As the conveyor belt 1 moves both the rubber skirts 5, 6 and the conveyor belt 1 are slowly eroded. Eventually, a gap will develop between the rubber skirts 5, 6 and the conveyor belt 1 allowing the material 2 to spill through the gap. It is therefore necessary to periodically replace both the skirts 5, 6 and the conveyor belt 1.

Shown m figure 2 is a conveyor belt 1 and first and second guide walls 7, 8 of a guide arrangement according to the invention. The conveyor belt carries material from the right to the left of the page. The first and second guide walls 7, 8 are arranged parallel to the direction of travel and close to the edges of the belt. Only the first guide wall 7 will be described m detail, the second guide wall 8 being a mirror image of the first guide wall 7.

Shown m figure 3 is the conveyor belt 1 and the first guide wall 7 of figure 2 in side view. The conveyor belt 1 carries material 2 from right to left as shown. Associated with the first guide wall is a restraining means which comprises first and second return pulleys 9, 10. The return pulleys 9, 10 are free to rotate about respective axes 11, 12. Extending between the first and second return pulleys 9,

10 is a sealing skirt 13 m the form of an endless loop. In this embodiment the sealing skirt 13 is rubber. Other embodiments may comprise sealing skirts of other flexible materials .

The first and second return pulleys 9, 10 are arranged so that the sealing skirt 13 engages with the top face of the conveyor belt 1 as shown, so forming a seal with the conveyor belt 1. This seal prevents the spillage of material

2 from the side of the moving conveyor belt 1. As the conveyor belt 1 moves, the friction between the sealing skirt 13 and the conveyor belt 1 causes the sealing skirt 13 to rotate m a clockwise direction as shown. The portion of the sealing skirt 13 in contact with the conveyor belt 1 moves m the same direction as the conveyor belt 1 and at substantially the same speed, so eliminating (or at least minimising) frictional wear of the conveyor belt 1 and the sealing skirt 13.

Covering the sealing skirt 13 is a guide plate 14. The guide plate 14 is connected to the frame (not shown) which supports the conveyor belt 1 and is stationary with respect to the axes 11, 12 of rotation of the first and second return pulleys 9, 10.

Shown m figure 4 is the conveyor belt 1 and the first and second guide walls 7, 8 of figure 2 shown in end view. The guide plate 14 covering the sealing skirt is substantially U shaped in cross section and comprises an inner wall 15, an outer wall 16 and a base 17. Both the mner wall 15 and the outer wall 16 are slightly separated from the conveyor belt 1 to prevent frictional damage to the conveyor belt 1. The inner and outer walls 15, 16 define a mouth 17 which opens towards the conveyor belt 1. The sealing skirt 13 is constrained between the inner and outer walls 15, 16 of the guide plate 14 as shown.

The guide plate 14 covers the moving sealing skirt 13 and so reduces the risk of accidental injury to people standing close to the conveyor belt 1. In this embodiment the guide plate 14 is a metal although other rigid materials are possible.

As can be seen from figure 4, the first and second guide walls 7, 8, in combination with the conveyor belt 1 form a generally U shaped moving trough for the transport of material 2.

In an alternative embodiment (not shown) the return pulley is driven by an external rotation means. This enables the first and second sealing skirts to be rotated independently of the conveyor belt. A feedback device connected between the conveyor belt and the rotation means ensures that the conveyor belt and sealing skirts move at the same linear speed.

Therefore, the described embodiments of the invention allow a conveyor run (or at least part of a conveyor run) to convey material from one location to another, and to be shielded from lateral spillage of material from the conveyor by a guide arrangement having a low friction engagement with the conveying surface of the conveyor. Preferably, the guide arrangement comprises two separate guide walls, each engageable with a respective side margin of an endless conveyor belt.

Claims

1. A guide arrangement for use with an endless conveyor to prevent material from spilling from the conveyor, the guide arrangement comprising: a sealing skirt which is arranged to engagae against the conveyor to form a seal therewith; and, a restraining means adapted to maintain the sealing skirt m contact with the conveyor; characterised in that: the sealing skirt is engageable with the conveyor and is arranged to move m the same direction as the conveyor.

2. A guide arrangement as claimed in claim 1, further comprising a guide plate remote from the conveyor, the guide plate being adapted to constrain the motion of the sealing skirt .

3. A guide arrangement as claimed in claim 1 or 2 , wherein the guide plate is substantially U shaped m cross section comprising a base and inner and outer side walls, the inner and outer walls defining a mouth which opens towards the conveyor belt; and, the sealing skirt being constrained between the inner and outer walls.

4. A guide arrangement as claimed in any one of claims 1 to 3, wherein the restraining means comprises at least two return pulleys and the sealing skirt comprises an endless loop extending therebetween.

5. A guide arrangment as claimed in claim 4, the sealing skirt being arranged to move with the conveyor due to the friction between the sealing skirt and the conveyor.

6. A guide arrangement as claimed m claim 4, wherein at least one of the return pulleys is connected to an external rotation means for rotating the return pulley, the return pulley in turn driving the movement of the sealing skirt .

7. A guide arrangement as claims m any one of the preceding claims, and comprising two separate guide walls each engageable with a respective side margin of an endless conveyor belt.

8. A guide arrangement as claimed in any one of the preceding claims, in combination with an endless conveyor belt.