WO2021069910A1

WO2021069910A1 - Conveyor Belt Cleaner Assembly

Info

Publication number: WO2021069910A1
Application number: PCT/GB2020/052505
Authority: WO
Inventors: Matthew BEVERLEY
Original assignee: Hoverdale UK Limited
Priority date: 2019-10-09
Filing date: 2020-10-09
Publication date: 2021-04-15
Also published as: GB2588143B; GB2588143A; GB201914597D0

Abstract

A conveyor belt cleaner assembly, for scraping the surface of a conveyor belt, the assembly comprising a horizontal support bar having a first end and a second end, the horizontal support bar being mounted on a first end support mount and a second end support mount, the horizontal support bar being moveable with respect to the first and second end mounts, so as to be moveable towards and away from the surface of a conveyor belt to be scraped in use, characterised in that the horizontal support bar is rotatably mounted on the first and second end supports.

Description

Conveyor Belt Cleaner Assembly

Technical Field

The invention relates to a conveyor belt cleaner assembly for use on a conveyor belt apparatus, and to a conveyor belt apparatus comprising the assembly.

Background

Conveyor belts are used in a wide variety of industries to transport solid material. In some cases liquid material may also be included with the solid material, which can make transport more challenging.

Conveyor belts generally have an endless loop formation, wherein an upper surface of the conveyor belt carries solid material to be transported, which loops back as a lower surface after passing around an end roller. In general the solid material carried by the upper surface is held in place due to gravity. Likewise, gravity causes the solid material to fall off the conveyor belt as it moves past an end roller. However in many industries it is not sufficient to rely on gravity to release all of the solid material from the conveyor belt, particularly where some liquid material is also present.

To address this, so-called conveyor belt cleaners are employed which act to scrape the lower surface of the conveyor belt to assist in the removal of solids that have not fallen off the conveyor belt due to gravity alone.

A common arrangement of conveyor belt scraper comprises a horizontal support bar wherein a scraper blade is mounted upon the horizontal support bar arranged to provide a scraping action on the surface of a conveyor belt. The scraper blade may be a physical blade in contact with the conveyor belt or it can be a gas blade, which applies a high pressure to the surface of the conveyor belt to achieve the scraping action.

Conveyor belt cleaners comprises a scraping blade maintain a small amount of pressure on the lower surface of the conveyor belt, so as to maintain good contact with the belt. Typically such scraping blades are made of a hard-wearing material such as tungsten carbide and the like. However, such scraping blades inevitably suffer from a significant rate of wear and this has the effect of reducing the amount of pressure exerted onto the surface of the conveyor belt, reducing its scraping performance.

One way of ensuring that there is a constant scraping force applied to the scraper is to have a resilient connection between the scraping blade and a rigid supporting structure.

For example, US 3,841 ,470 discloses a cleaner for a conveyor belt which has a plurality of cleaner blades, each of which are mounted on a horizontal support bar by a respective resilient member. Also, US 6,227,350 discloses a cleaner for a conveyor belt which has a plurality of cleaner blades, each of which are mounted on a horizontal support bar by a shared pressurised fluid, that ensures each cleaner blade exerts the same pressure on a conveyor belt in use.

However, such conveyor belt cleaners require cleaning and/or maintenance on a regular basis, particularly when the solid material being handled is difficult to handle or also contains liquid material. For example, blockages can occur if solid material becomes lodged between the assembly and the conveyor belt apparatus.

Improvements in this area would therefore be desirable.

Detailed Description of the Invention

In a first aspect, the invention relates to a conveyor belt cleaner assembly, for scraping the surface of a conveyor belt, the assembly comprising a horizontal support bar having a first end and a second end, the horizontal support bar being mounted on a first end support mount and a second end support mount, the horizontal support bar being moveable with respect to the first and second end mounts, so as to be moveable towards and away from the surface of a conveyor belt to be scraped in use, characterised in that the horizontal support bar is rotatably mounted on the first and second end supports.

Preferably the horizontal support bar is vertically moveable towards and away from the surface of the conveyor belt.

The cleaner assembly may be arranged to provide a scraping action by means of a physical scraper, wherein a scraper blade is mounted upon the horizontal support bar arranged to provide a scraping action on the surface of a conveyor belt. Alternatively, the scraping action can be provided by a blade of flowing gas ejected from a gas delivery means located along the horizontal support bar.

By arranging for the horizontal support bar to be rotatably mounted, the scraper blade can be easily rotated away from a cleaning position to a maintenance position, providing an easily accessible space for cleaning and maintenance. It is not necessary for any biasing to be applied to the horizontal support bar in a rotational sense, as the rotating action is not intended to apply any pressure onto the surface of the conveyor belt.

Preferably the horizontal support bar is also vertically slideably mounted, so that it is vertically moveable. This allows for the horizontal bar to be raised and lowered, e.g. between a scraping position (where it is engaged with the conveyor belt) and a cleaning/maintenance position where it is moved away from the conveyor belt to provide a convenient space within which to carry out cleaning and/or maintenance.

The horizontal support bar is therefore preferably capable of two modes of movement with respect to the end support mounts, a vertical movement towards and away from the conveyor belt surface, and a rotational movement, to allow the blade to rotate away into a maintenance position.

In order to facilitate the movement of the horizontal support bar, it is preferable that the conveyor belt cleaner assembly comprises a handle means to enable an operator to move the position of the horizontal support bar. Alternatively, the movement of the horizontal bar may be motorised.

In the case when the horizontal support bar comprises a scraper blade, it is preferable that the horizontal support bar is biased towards the conveyor belt surface, as this provides a constant pressure on the surface of the conveyor belt. Such biasing is preferably applied in vertical upwards direction to provide vertical upwards movement of the horizontal support bar. Additionally, as the scraper wears down or other mechanical changes occur, the biasing, e.g. by a pressurised fluid, will ensure that constant pressure is maintained without the need for adjustment of the horizontal bar position by an operator. Additionally, the scraper blade does not need to be attached to the horizontal bar by an elastomeric material, and can be rigidly attached, which means that the entire assembly can be made more resistant to corrosive material. It has been found that a gas spring provides a convenient way of delivering a constant upwards force onto the horizontal support bar and would not be affected by a build-up of dirt or corrosion and provides a consistent force over time. Thus, preferably the horizontal support bar is biased towards a position towards the surface of a conveyor belt to be scraped in use by at least one gas spring.

Preferably a first gas spring is provided on the first end support mount and a second gas spring is provided on the second end support mount.

The vertical biasing, e.g. by a gas spring, exerts a linear upwards force on the horizontal support bar. It may be desirable to be able to disengage the biasing means e.g. gas spring from the horizontal support bar, in order to remove this upwards force, for example when cleaning or replacing a blade. It is therefore preferable that the biasing means e.g. gas spring acts on a cammed surface, so that rotation of the cammed surface can cause the disengagement of the upwards force from being transferred to the horizontal support bar.

The cammed surface is preferably attached to the horizontal support bar, to provide it with the ability to rotate with respect to a gas ram.

Thus, the rotation of the horizontal support bar may also cause the removal of the upwards biasing force from the horizontal support bar. In this way, a single rotational movement of the bar can move it from a cleaning position to a maintenance position in a single combined rotational and vertical movement.

The conveyor belt cleaner assembly may be fitted to a conveyor belt apparatus in known manner without any significant modifications of existing conveyor belt lines being necessary.

Thus, in a second aspect, the invention relates to a conveyor belt apparatus comprising a conveyor belt cleaning assembly described herein. Typically, the arrangement is such that the horizontal support bar is positioned beneath a horizontal section of the conveyor belt, so that any vertical upwards movement of the horizontal support bar brings any attached scraper into contact with the conveyor belt surface. Additionally, any upwards biasing provides a constant upwards pressure of the scraper blade onto the conveyor belt surface, as discussed above. The invention will now be illustrated, byway of example, and with reference to the following figures, in which:

Figure 1 is perspective view of a conveyor belt apparatus in combination with a conveyor belt cleaner assembly according to the present invention.

Figure 2 is a side sectional view at a slight angle of the conveyor belt apparatus shown in figure 1.

Figure 3 is a perspective view of a conveyor belt cleaner assembly according to the present invention.

Figure 4 is a perspective view of the conveyor belt cleaner assembly shown in figure 3 in a cleaning and maintenance position.

Figure 5 is a side sectional view through a first end support mount of the conveyor belt cleaner assembly shown in figure 3.

Figures 6a and 6b show perspective half-views of a second conveyor belt cleaner assembly according to the present invention.

Figure 7 is a side sectional view through an alternative end support mount.

Turning to the figures, figures 1 and 2 show a conveyor belt apparatus 10 with a conveyor belt cleaning assembly 12 fitted to it. The conveyor belt apparatus 10 comprises a conveyor belt 14 having an upper forwardly travelling surface 16 and a lower return run surface 18 and being driven by roller 20.

The conveyor belt cleaner assembly 12 comprises a horizontal support bar 22 and a first end support mount 24 and a second end support mount 26. Mounted on the horizontal support bar 22 is a scraper blade 28. The scraper blade 28 is connected to the horizontal support bar 22 via support plates 30 and 32.

As can be seen, conveyor belt cleaning apparatus 12 is positioned beneath the conveyor belt apparatus, so that the scraper blade 28 is in contact with the horizontal lower return run surface 18 of the conveyor belt 14. In use, as the conveyor belt apparatus 10 operates to rotate roller 20, and solid material (not shown) is carried on top of the upper forwardly travelling surface 16. The majority of the solid material leaves the surface of the conveyor belt 14 due to gravity as the belt 14 travels around roller 20. Any solid material that remains adhered to the surface of the conveyor belt 14 on the lower return run surface 18 are then scraped off from the surface 18 by scraper blade 28.

Figures 3 to 5 show the conveyor belt cleaner assembly 12 isolated from the conveyor belt apparatus 10. The horizontal support bar 22 is mounted at its first and second ends to first end support mount 24 and second end support mount 26 respectively.

It will be noted that the ends of horizontal support bar 22 extend beyond the first 24 and second 26 end support mounts. Attached to the ends of the horizontal support bar are cammed blocks 54, 56. It can also be seen that gas springs 64, 66 are mounted on support platforms 40. Extending from each cammed block 54, 56 is a handle 60, 62.

First end support mount 24 comprises first vertical support plate 34 and second vertical support plate 36. The first 34 and second 36 vertical support plates are connected at their upper ends by metal block 38 and connected at their lower ends by support platform 40. Attached to the interior surfaces of the first 34 and second 36 vertical support plates are a pair of nylon travel surfaces 42, each comprising a vertical slot. Positioned between the pair of nylon surfaces 42 is a nylon bush 50 that is positioned within the slots in the pair of nylon travel surfaces 42 allowing the bush 50 to travel vertically within the end support mount 24. Second end support mount 26 is a mirror image to the first end support mount 24, and therefore does not need to be separately described.

The nylon bush 50 comprises a cylindrical hole 51 in its centre, lined with a stainless steel cylinder 52. One end of horizontal support bar 22 passes snugly within the cylinder 52. Thus, by virtue of the mounting within the cylinder 52, the horizontal support bar 22 is rotatably mounted within the end support mount 24. Also, by virtue of the mounting of the nylon bush 50, the horizontal support bar 22 is also slideably mounted on the first end support 24.

In use, as shown in figure 3, gas springs 64, 66 act to apply upwards pressure onto cammed blocks 54, 56 respectively. This is translated to upwards force acting on both ends of horizontal support bar 22. By virtue of the horizontal support bar 22 being vertically slideably mounted in first 24 and second 26 end supports, the horizontal support bar is biased to an upwards position. Upwards movement is limited to the ends of the vertical slots in the nylon travel surfaces 42, however before that limit is reached, the arrangement is such that the scraper 28 contacts the conveyor belt 14 and applies pressure thereto, the reaction to which prevents further vertical upwards movement of the horizontal support bar 22

As the scraper blade wears away in use, a constant pressure is nevertheless exerted onto the conveyor belt due to the action of the gas springs 64, 66.

Ultimately, the scraper blade 28 will need replacing, or possibly the assembly may require cleaning or other maintenance issues such as removing a blockage or trapped article.

In the case of cleaning or maintenance being required, the movement of the conveyor belt will be stopped and an operator will actuate one or both of handles 60, 62, in order to place the assembly 12 into a clean and maintenance position, as shown in figure 4.

As the handles 60, 62 are actuated, by virtue of the horizontal support bar 22 being rotatably mounted, this causes rotation of the horizontal support bar, which in turn rotates the attached scraper blade 28, 30, 32. As shown in figure 4 this could involve a 90° rotation, or similar degree of movement.

As the gas springs act on cammed blocks 54, 56 the transfer of the upwards force from the gas springs is reduced until it is removed completely once the horizontal support bar has reached the position shown in figure 4. Thus, not only is the scraper blade 28, 30, 32 rotated away from the conveyor belt but also the horizontal support bar moves downwards somewhat, as permitted by the vertical slots in the nylon travel surfaces. This leaves an accessible space for an operator to replace a scraper blade and/or to perform a cleaning or maintenance operation.

Once the cleaning and maintenance has been completed, an operator can actuate handles 60, 62 to return the assembly to the position shown in figure 3 and the conveyor belt apparatus 10 can be restarted. Figures 6a and 6b show a second embodiment of conveyor belt cleaner 80 which does not have a physical blade and instead provides a blade of gas onto the surface of the conveyor belt 14 to be cleaned.

Shown is a cylindrical horizontal support bar 82 mounted at its first and second ends to first end support mount 84 and second end support mount (not shown) respectively. Mounted on the horizontal support bar 82 is a compressed gas delivery housing 88, which has a gas blade exit slot 89 exiting therefrom.

First end support mount 84 comprises a nylon bush 90 that is positioned within guide rails 86 allowing the bush 90 to travel vertically within the end support mount 84. Attached to the end of horizontal support bar 82 is a handle 92.

The nylon bush 90 comprises a cylindrical hole in its centre, lined with a stainless steel cylinder. One end of horizontal support bar 82 passes snugly within the bush 90. Thus, by virtue of the mounting within the bush 90, the horizontal support bar 82 is rotatably mounted within the end support mount 84. Also, by virtue of the mounting of the nylon bush 90, the horizontal support bar 82 is also slideably mounted on the first end support 84

In use, as shown in figure 3, support rod 91 acts to apply upwards pressure onto bush 90. This is translated to upwards force acting on the horizontal support bar 82. Upwards movement is limited to the ends of the vertical slots in guide rails 86.

Ultimately, the assembly may require cleaning or other maintenance issues such as removing a blockage or trapped article. In the case of cleaning or maintenance being required, the movement of the conveyor belt will be stopped and an operator will actuate handles 92, in order to place the assembly 80 into a clean and maintenance position, as shown in figure 6b.

As the handle 92 is actuated, by virtue of the horizontal support bar 82 being rotatably mounted, this causes rotation of the horizontal support bar, which in turn rotates the attached gas blade 89. As shown in figure 6b this could involve a 90° rotation, or similar degree of movement. In addition, the upwards force from the support rods 91 can be removed, allowing the bush 90 to move downwards within guide rails 86. Thus, not only is the gas blade 89 rotated away from the conveyor belt but also the horizontal support bar moves downwards somewhat. This leaves an accessible space for an operator to replace a scraper blade and/or to perform a cleaning or maintenance operation.

Once the cleaning and maintenance has been completed, an operator can actuate handle 92 to return the assembly to the position shown in figure 6a and the conveyor belt apparatus 10 can be restarted.

Figure 7 shows a side sectional view through an alternative first end support mount 100 showing the detail of a cammed block 102. Shown is a gas spring 104 having a moveable shaft 105 with a ball bearing 106 at its end. In the figure the conveyor belt scraper is shown in its scraping position. The cammed surface 108 comprises an indent 110 that matches the profile of the ball bearing 106 to maintain the conveyor belt scraper in the scraping position. The thickness of the cammed surface 108 varies gradually with respect to the centre of rotation, providing the cammed surface function, as will be described.

When it is desired to move the conveyor belt scraper into a cleaning and maintenance position, cammed block 102 is rotated in a clockwise or anticlockwise manner. This is met by an initial resistance by the ball bearing leaving the indent 110 as the shaft 105 is pressed into the gas spring 104. As the cammed block 102 is further rotated the shaft 105 gradually leaves the gas spring 104 until the ball bearing bears against the final position 112 on the cammed surface 108. At this point the shaft 105 has reached its maximum position and no longer applies an upwards force onto the horizontal bar 22. This not only leaves an accessible space for an operator to replace a scraper blade and/or to perform a cleaning or maintenance operation but also ensures that any upwards force on the horizontal bar 22 is removed to aid cleaning and to increase the space available.

Claims

1. A conveyor belt cleaner assembly, for scraping the surface of a conveyor belt, the assembly comprising a horizontal support bar having a first end and a second end, the horizontal support bar being mounted on a first end support mount and a second end support mount, the horizontal support bar being moveable with respect to the first and second end mounts, so as to be moveable towards and away from the surface of a conveyor belt to be scraped in use, characterised in that the horizontal support bar is rotatably mounted on the first and second end supports.

2. A conveyor belt cleaner assembly according to claim 1, wherein the horizontal support bar is vertically moveable towards and away from the surface of the conveyor belt.

3. A conveyor belt cleaner assembly according to claim 1 or claim 2, wherein a scraper blade is mounted upon the horizontal support bar arranged to provide a scraping action on the surface of a conveyor belt.

4. A conveyor belt cleaner assembly according to claim 1 or claim 2, wherein a gas blade delivery means is mounted upon the horizontal support bar arranged to provide a scraping action on the surface of a conveyor belt.

5. A conveyor belt cleaner assembly according to any one of the preceding claims, wherein the horizontal support bar is vertically slideably mounted on the first and second end supports.

6. A conveyor belt cleaner assembly according to any one of the preceding claims, which comprises a handle means to enable an operator to move the position of the horizontal support bar.

7. A conveyor belt cleaner assembly according to any one of the preceding claims, wherein the horizontal support bar is biased towards a position towards the surface of a conveyor belt to be scraped in use.

8. A conveyor belt cleaner assembly according to claim 8, wherein the biasing is applied in a vertical upwards direction to provide vertical upwards movement of the horizontal support bar

9. A conveyor belt cleaner assembly according to claim 7 or claim 8, wherein the horizontal support bar is biased towards a position towards the surface of a conveyor belt to be scraped in use by pressurised fluid.

10. A conveyor belt cleaner assembly according to claim 7, wherein the horizontal support bar is biased towards a position towards the surface of a conveyor belt to be scraped in use by at least one gas spring.

11. A conveyor belt cleaner assembly according to claim 8, wherein a first gas spring is provided on the first end support mount and a second gas spring is provided on the second end support mount.

12. A conveyor belt cleaner assembly according to claim 10 or claim 11, wherein the first end support comprises a cammed surface, onto which the gas spring acts.

13. A conveyor belt cleaner assembly according to claim 12, wherein the cammed surface is arranged to rotate with the rotation of the horizontal support bar.

14. A conveyor belt apparatus comprising a conveyor belt cleaning assembly according to any one of the preceding claims.

15. A conveyor belt apparatus according to claim 14, wherein the horizontal support bar is positioned beneath a horizontal section of the conveyor belt, so that any vertical upwards movement of the horizontal support bar brings any attached scraper into contact with the conveyor belt surface and any upwards biasing provides a constant upwards pressure of the scraper blade onto the conveyor belt surface, as discussed above.