GB2279275A - Cleaning system for endless conveyor belt - Google Patents

Abstract

A cleaning system for an endless open web conveyor belt 6 having a drive and/or return shaft 3 cleaning bars 2a, b mounted on the shaft whereby in use the bars protrude through the cross-bar spacings 18 so as to displace soil build-up 26 from the belt cross-bars 12. The trailing corner edges 20 of the bars are bevelled to facilitate entry of the bars into the spaces 18. <IMAGE>

Description

CLEANING SYSTEM The present invention relates to a cleaning system for use with an endless open web conveyor belt of the type used in harvesters, stone and clod separators, graders and the like, but not exclusively.

Cleaning devices for cleaning the spaces between open web conveyor belts are already known and usually comprise a discrete assembly of a plurality of more or less closely spaced apart narrow cleaning bars fixed to a shaft which is rotable in bearings. The assembly usually is mounted as an independent unit remote from the drive or return rollers at a generally planar section of the belt so as to engage on the inside face of the return side of the open web conveyor belt, (See Fig.1).

Such assemblies can be difficult to install in certain applications where available space is restricted and/or where other components e.g. stay bars, shafts etc. pass through the inside of the open web conveyor belt.

Moreover these conventional web cleaner assemblies are, due to the close proximity of the cleaning bars, susceptible to clogging up with material especially in certain heavy soil field conditions, thereby drastically reducing their effectiveness. Furthermore the cleaning bars on such known cleaning devices are required to be much narrower than the gap between the cross-bars of an open web conveyor belt so as to facilitate entry of the cleaning bars into the said gaps. This in turn results in failure of the narrow cleaning bars to clear away all the build up of material between the cross-bars and in particular they are not effective in cleaning off the build up of material on the leading edge of each cross-bar.It will be understood that if material such as soil builds up between the gaps on the cross-bars on the belt the screening capacity of the conveyor can be substantially reduced and altered which can be particularly serious in grading applications where the size of the cross-bar openings is critical to soil separation of a particular size of potato or any other object, and/or can necessitate a reduced operating speed.

It is an object of the present invention to avoid or minimize one or more of the foregoing disadvantages.

The present invention provides a cleaning system for an endless open web conveyor belt having a drive and/or return shaft with belt support and engagement means formed and arranged for guiding said belt around a generally part-circular pathway having a predetermined radius and said open web belt having a predetermined spacing between successive cross-bars, which cleaning system comprises a small plurality of cleaning bars mounted on said shaft with radially outward edges at a radial distance from said shaft at least slightly greater than said predetermined radius, said bars being substantially circumferentially spaced apart, and each having a circumferential extent not substantially less than said predetermined cross-bar spacing, said plurality of cleaning bars being mounted on said shaft so as to be rotatable relative to said shaft, whereby in use of the system said bars protrude through said cross-bar spacings so as to displace soil build-up from the belt cross-bars whilst substantially avoiding soil build-up on the cleaning bars.

Thus with a cleaning system according to the present invention the spacing between the successive cross bars of said open web conveyor belt may be cleaned of material in a simple and convenient manner without said cleaning system itself becoming clogged.

The cleaning system is conveniently mounted between the drive sprockets on the existing drive shaft of the conveyor belt drive means without the need for additional mounting brackets, shaft assemblies, bearing assemblies or the like. Preferably from two to five, desirably two or three, equidistantly spaced apart cleaning bars are mounted around said shaft. The cleaning bars are conveniently mounted on respective arms (or series of arms) projecting radially from collars or bushes (conveniently of split form) which are more or less freely rotatable about the drive or return shaft.In this way the bars may make small angular movements with respect the shaft so as to facilitate entry of the cleaning bars into the spaces between successive cross-bars even when there are minor irregularities in the spacing of the cross-bars for instance where a cross-bar is bent or displaced, Without such freedom of movement there is a problem of the web conveyor belt riding up over the cleaning bars and possibly even disengaging from the drive or return shaft sprockets. In order further to facilitate entry of the cleaning bars into the the spaces between the belt cross-bars, the radially outer trailing side corner edges are desirably bevelled so that they can slide over the leading edges of the trailing side cross-bars.

In use of the cleaning system the relatively wide radially outward edges of the cleaning bars are driven through the said cross-bar spacings so as to displace soil built up in said spacings with a generally piston-like action. Advantageously as the circumferential extent of said cleaning bars is not substantially less than the cross-bar spacing then substantially all the soil built up between said cross bar spacing is removed and there is no excess soil to fall back into the cleaning system thereby minimizing the possibility of soil build up around the cleaning bars themselves.

It will be appreciated that a cleaning system according to the present invention with only two or three cleaning bars will not clean every cross bar spacing in one pass of the conveyor belt but by using a number of cleaning bars which is not a factor of the total number of cross-bars in the conveyor belt, different cross-bar spacings will be cleaned at each pass of the endless open web conveyor belt around a cleaning system of the invention. Furthermore if desired, more than one cleaning system of the invention may be employed in such a conveyor belt e.g. one at each end.

Further preferred features and advantages of the present invention will appear from the following detailed description given by way of example of some preferred embodiments illustrated with reference to the accompanying drawings in which: Fig.l is a perspective view of a known type of cleaning device; Fig.2 a cutaway of a cleaning system according to the present invention; and Fig.3 is a side view in the direction of line A - A of the embodiment in Fig.2 A cleaning system of the invention, generally indicated by reference numeral 1 in Fig.2, comprises two cleaning bars 2a, b rotatably mounted on a drive shaft 3 between the drive/return sprockets 4a, b of an open web belt conveyor 6 drive mechanism.

In more detail a drive means (not shown) drives the drive/return sprockets 4a, b via the drive shaft 3 so that the teeth 10 of the sprockets engage with and drive the spaced apart cross-bars 12 of the belt conveyor 6 and thereby drive the belt conveyor 6. Each cleaning bar 2a, b is mounted on a respective pair of arms 14a, b projecting radially from drive shaft mounting collars 16a, b. The collars 16a, b have bearings (not shown) so that the cleaning bars 2 may freely rotate about the drive shaft 3.

In use, and with reference to Fig.3, as the belt conveyor 6 passes around the drive/return sprockets 4, the cleaning bars 2 make small angular movements 7 with respect to the drive shaft 3 so as to facilitate entry of the cleaning bars 2 into the spaces 18 between the spaced apart cross-bars 12. The radially outer trailing corner edges 20 are bevelled 22 so that they can slide over the leading edge 24 of the trailing side cross-bars 12 further to facilitate the entry of the cleaning bars 2 into the spaces 18 between the cross-bars 12 and thereby displace soil 26 that has built up on the leading edge 24 of the cross-bars 12. The width of the cleaning bars 2 is not substantially less than the space 18 between the cross bars 12 so that all the soil that has built up is removed.

As will be seen from Fig.3 not all the cross-bars passing around the cleaning system 1 have the soil removed because not every space 18 between the cross-bars 12 is cleaned on each pass of the belt.

After several passes though, all the spaces 18 between the cross-bars 12 will eventually be cleaned.

It will be appreciated that various other modifications may be made to the above described embodiment without departing from the scope of the present invention. Thus for example more than one cleaning system of the invention may be used in a harvester, separator or the like e.g. one at each end. In yet another form of the invention the arms on which the cleaning bars are mounted may have a degree of resilience further to facilitate small angular movements of the cleaning bars with respect to the shaft and thereby facilitate entry of the bars into the spaces between the cross-bars.

Claims (13)

1. A cleaning system for an endless open web conveyor belt having a drive and/or return shaft with belt support and engagement means formed and arranged for guiding said belt around a generally part-circular pathway having a predetermined radius and said open web belt having a predetermined spacing between successive cross-bars, which cleaning system comprises a small plurality of cleaning bars mounted on said shaft with radially outward edges at a radial distance from said shaft at least slightly greater than said predetermined radius, said bars being substantially circumferentially spaced apart, and each having a circumferential extent not substantially less than said predetermined cross-bar spacing, said plurality of cleaning bars being mounted on said shaft so as to be rotatable relative to said shaft, whereby in use of the system said bars protrude through said cross-bar spacings so as to displace soil build-up from the belt cross-bars while substantially avoiding soil build-up on the cleaning bars.

2. A cleaning system according to claim 1 mounted between the web engagement sprockets of said drive and/or return shaft of said endless open web conveyor belt.

3. A cleaning system according to claim 1 or claim 2 wherein from two to five angularly spaced apart cleaning bars are mounted around said shaft.

4. A cleaning system according to claim 3 wherein two or three equidistantly spaced apart cleaning bars are mounted around said shaft.

5. A cleaning system according to any one of claims 1 to 4 wherein each said cleaning bar is mounted on at least one arm projecting radially from a bearing means on said drive and/or return shaft.

6. A cleaning system according to any one of claims 1 to 5 wherein said cleaning bars have a bevelled, radially outer trailing side corner edge.

7. A cleaning system according to any one of claims 1 to 6 wherein said cleaning bars have a circumferential extent not substantially less than said predetermined cross-bar spacing.

8. A cleaning system according to any one of claims 1 to 7 wherein said cleaning bars are mounted resiliently on said shaft.

9. A cleaning system substantially as described hereinbefore and with particular reference to Figs. 2 and 3 of the accompanying drawings.

10. An endless open web conveyor belt system having at least one cleaning system according to claim 1.

11. A harvester having a conveyor belt system according to claim 10.

12. A separator having a conveyor belt system according to claim 10.

13. A grader having a conveyor belt system according to claim 10.