GB2399779A - Grader - Google Patents

Abstract

A separating device for solids, especially produce such as potatoes from debris such as soil, including an apertured grading element, preferably in the form of an endless belt 18, and a detritus separator, preferably in the form of a at least one driven roller 50, 55 providing a rotating rebounding surface. A bypass element such as a reversible conveyor belt 26 may be provided between the grading element and the detritus separator to selectively divert produce and detritus either towards or away from the detritus separator, preferably by moving the bypass element between two positions. Receptacles such as conveyor belts 36, 37 may be provided for the separated material. Rotary brushes 53, 58 may be provided to clean the rollers.

Description

PATENTS ACT 1977 A10767GB-RAL Title: Grader

Description of Invention

This invention relates to a grader operable to grade produce, particularly root produce and more particularly potatoes and separate the graded produce from detritus such as stones or soil clods mixed with the produce.

Conventionally, it is necessary to grade produce, that is separate the produce into produce of appropriate size ranges, and to separate the produce from any undesirable material or detritus that has been mixed up with the produce. In the particular example of root vegetables the detritus may comprise stones and clods of soil which have been mixed with the root vegetables during the harvesting process. Conventionally, the mixture of produce and detritus is separated and then the produce is transferred to a grading machine for grading.

The multiple processing stages have a number of disadvantages. With produce that can be bruised or damaged, it is desirable to minimise movement and processing steps, and thus reduce the number of stages where bruising or damage can occur. As the produce has to be transported between grading and separating machines, the produce can be damaged not only in the grading and separating steps but also the journeys between machines.

According to the invention, we provide a grader for produce, the grader comprising a grading element having a plurality of apertures, the grading element being operable to receive a mixture of produce and detritus, the grader further comprising a detritus separator, the detritus separator being operable to receive produce and detritus from the grading element and separate the detritus and produce.

The grader may further comprising a bypass element, the bypass element being disposed below the grading element, the bypass element being operable to direct produce and detritus towards the detritus separator or away from the detritus separator.

The bypass element may comprise a conveyor belt assembly having a conveyor belt to receive produce and detritus.

The conveyor belt assembly may comprise a drive operable to drive the conveyor belt in a first direction to direct the produce to the detritus separator and in a second direction to direct produce away from the detritus separator.

The conveyor assembly may be movable between a first position to direct produce to the detritus separator and a second position to direct produce away from detritus separator.

The bypass element may be operable to direct produce away from the detritus separator and to a first receptacle.

The bypass element may further comprise a second conveyor belt operable to receive produce from the conveyor assembly and direct produce to the first receptacle.

The detritus separator may comprise a driven roller whereby produce falling on the roller is directed to a first outlet and detritus landing on the roller is directed towards a second outlet.

The grader may further comprise a brush to remove soil from the driven roller.

The brush may comprise a driven rotary cleaning brush.

The grader may comprise a further driven roller, whereby produce falling on the further driven roller is directed towards the driven roller.

The first outlet may comprise a first conveyor belt and the second outlet comprises a second conveyor belt.

The grading element may comprise a foraminous belt.

The bypass element may be disposed below the grading element and the detritus separator is disposed below the bypass element.

The present invention will now be described by way of example with reference to the accompanying drawings wherein; Figure 1 is a diagrammatic side view of a grader embodying the present invention, Figure 2 is a plan view of the grader of Figure 1, Figure 3 is a perspective view of the grader of Figure 1, Figure 4 is a still further perspective view of the grader of Figure 1, Figure 5 is a still further perspective view of the grader of Figure 1, and Figure 6 is a diagrammatic side view of a further grader embodying the present invention.

Referring now to the Figure 1, a grader embodying the present invention is generally shown at 10 as best seen in Figures 3 to 5, the grader has a body generally indicated at 11 comprising a pair of opposed generally trapezoidal side walls 12, 13 and a front wall 14. The grader is supported on a plurality of legs 15 connected to a base frame 16. Mounted on the base frame 16 are lifting means 17, in the present example channel sections to receive the forks of a suitable load handling machine such as a fork lift truck.

The grader 10 is provided with a grading element generally shown at 18 and comprising a foraminous belt. In the example of Figure 4 the foraminous belt comprises a continuous belt made of metal links, but may be provided of any other material as appropriate, such as a plastics material belt with appropriate apertures. The apertures in the grading element 18 are selected to allow produce up to a desired maximum size to pass through the belt. The belt 18 is continues and is supported on rollers 20_, 20b, 20c, 20_ and 20_. The rollers 20_, 20b, 20c, 20_ and 20e extend between and are supported by the side walls 12, 13. An appropriate drive for the belt 18 is shown at 21 in the Figures to drive the belt in a direction indicated by arrow A. As is apparent from the drawings and in particular Figure 1, an upper run 18a of the belt 18 is supported by rollers 20a, 20b below an upper edge 12g, 13a of the side walls 12, 13 to prevent produce falling off the sides ofthe belt 18.

An in-feed belt 22 is provided located over a front part of the upper run 18a of the belt 18 extending between the walls 12, 13 and in similarly provided with its own drive, operable to receive the produce and convey it onto the upper run 18a of the belt 18. Agitators 23 are disposed located below the upper run 18a of the belt 18 to shake to encourage produce to pass through the holes of the upper run 18a and to avoid produce becoming stuck. A declogger roller 24 is shown located towards the rear of the upper run 18a of the belt 18 to dislodge any produce or detritus which may have become trapped in the apertures of the belt 18.

A bypass element 25 is disposed between the side walls 12, 13 and below the upper run 18a of the belt 18 to receive produce and detritus which passes through the belt 18. The bypass element 25 comprises a conveyor belt assembly 26 having a conveyor belt 27 supported on end rollers 28. The conveyor belt assembly 26 is received in an elongate slot 29 in the side walls 12, 13 and is slidably movable therein by an appropriate control, in this case a manually operated crank 30. The conveyorbelt assembly 26 is further provided with a drive 31 which is operable to drive the conveyor belt 27 in either direction.

Located below a forward end of the conveyor belt assembly 26 is a detritus separator generally indicated at 32. The detritus separator 32 comprises a roller 33 which is driven by a motor generally shown at 34 and movable in a forwards and backwards direction by on a movable support 35a, in this example by a manually operated control 35b. The roller 33 in this example is 200mm in diameter and has a plain steel machine surface, or can be made up with segmental rings to provide a roller of the desired width. Produce and detritus falling onto the driven roller 33 are deflected by different amounts. To receive the produce and detritus from the roller 33 a first receptacle comprising a produce conveyor 36 and a second receptacle to receive the detritus comprising a detritus conveyor belt 37. A divider 38 is located above the conveyors 36, 37 and comprises an adjustment mechanism whereby the position of the divider 38 relative to the roller 33 and the conveyors 36, 37 can be adjusted.

The roller motor 34 is also of variable speed to allow the speed of the rollers to be adjusted to provide the desired separation of produce and the detritus.

A second conveyor 40 is located behind a rearward end of the conveyor assembly 26 to receive detritus and produce from the conveyor assembly 26 and pass it to the produce conveyor 36.

To ensure produce and detritus passing through the belt 18_ is directed onto the conveyor assembly 26, an appropriate deflector 18_ is provided.

To ensure that produce and detritus from the conveyor assembly 26 is directed onto the roller 33, an appropriate deflector 33_ is provided.

To keep the roller 33 clear of soil, a motorised rotary cleaning brush 33_ is provided behind a forward surface of the roller 33 and in contact therewith to dislodge any soil which has become attached to the surface ofthe roller 33.

In addition, a spay bar 39 is provided extending alongside the roller 33 and above the brush 33b. The spray bar 39 extends along the length of the roller 33 and comprises a tube with holes along its length and which may be connected for a water supply such that the spray bar 39 drips water onto the roller 33 and brush 33b to assist in cleaning the surface ofthe roller 33.

The grader 10 is operated as follows. When it is desired to perform grading and separation steps, the conveyor assembly 26 is moved to a first position, that is to the right as shown in Figure 1 and the conveyor belt 27 is run to direct produce in a forward direction, that is to the left as shown in Figure 1 towards the roller 33. The produce on the conveyor 27 is allowed to fall onto the roller 33 and is separated from the detritus, with the detritus falling to the left of the separator 38 and being directed to the detritus conveyor 37 and the produce falling to the right of the divider 38 and being directed to the produce conveyor 36. The produce conveyor 36 and detritus conveyor 37 may be run to direct the produce and detritus to outlets on whichever side of the grader 10 is desired. The various parts of the detritus separator are adjustable so that the roller 33 may be moved in a forwards and rearwards direction and the divider 38 moved in a forwards and rearwards direction using the adjustment mechanism 39 to provide the desired separation of detritus and produce.

Where appropriate, it may be desired to operate to the grader 10 whilst bypassing the detritus separator 32. To do so, the conveyor assembly 26 is moved to the left in the slots 29 as shown in Figure 1 to a second position. The motor 34 is operated to drive the conveyor belt 27 such that the upper run moves to the right as shown in Figure 1. Produce passing through the upper run 18_ of the belt 18 will then be conveyed to the right by the conveyor belt 27 and will be received by the second conveyor 40. The second conveyor 40 will then carry the produce to the produce conveyor 36.

The grader 10 is thus particularly advantageous in that produce can be graded and separated from detritus with no transport step and with the minimum of operations. Where desirable, the detritus separator 32 can be bypassed, for example, where little or no detritus is mixed in with the received produce. The positioning of the detritus separator and bypass element within the circuit of the belt 18 and below the upper end of the belt 18 permits the grader 10 to be a particularly compact device. In the present example, the overall length of the grader is 2528mm and the overall height, excluding the base frame, is 1687mm and the width of the device excluding the produce conveyor 36 and detritus conveyor 37 is 2812mm. Thus, the grader 10 is particularly compact and may be easily transported where desired.

Referring now to Figure 6, a grader 10' is shown which is similar to the grader 10 except that it is provided with a detritus separator 32' comprising a pair of driven rollers. As seen in Figure 6, the detritus separator 32 comprises a first roller 50 and a movable support 51, adjustable to move the roller 50 to the left and right as shown in Figure 6 by a manual control 52. In like manner to the grader 10 of Figures 1 to 5, a driven rotary brush 53 is provided alongside the roller 50, and a spray bar 54 is located above the rotary bush 53 and alongside the roller 50 to assist in keeping the surface of the roller 50 clear of soil. The detritus separator further comprises a second roller 55 located above and to the left of the first roller 50 as shown in Figure 6. Similarly, the roller 55 is supported on a movable support 56 adjustable by a manual control 57 and is provided with a driven rotary brush 58 and a spray bar 59, in this case located above the roller 55. The grader 10' is provided with a second conveyor 40' in like manner to the second conveyor 40 of the grader 10, but in view of the increased height of the detritus separator 32', the second conveyor 40' is inclined at a steeper angle and is apparent from Figure 6.

In operation, the grader 10 operates in a similar manner to the grader 10 of Figure 1. Produce and detritus passing through the belt 18, is conveyed, where separation is required, by the conveyor belt assembly 26 to the detritus - separator 32'. The produce and detritus falling from the conveyor belt assembly 26 lands on the second roller 55 which will deflect the produce and detritus by separate amounts. The produce and/or detritus will then fall from the second roller 55 and fall onto the first roller 50, and will be deflected further, such that the detritus lands on the detritus conveyor 37 and the produce lands in the produce conveyor 36. As before, the speed of the rollers 50, 55, their positions on the adjustable supports 51, 56 and the position of the adjustment means 38 between the conveyors 36, 37 can be varied as necessary to optimise the separation of detritus and produce.

Although a grader 10 as described herein is particularly appropriate for root produce and particularly for grading and separating small potatoes grown in heavy soil it will be appropriate that the present invention may be used with any appropriate produce or mixture of produce and detritus as desired.

In the present specification "comprises" means "includes or consists of" and "comprising" means "including or consisting of".

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims (16)

1. A grader for produce, the grader comprising a grading element having a plurality of apertures, the grading element being operable to receive a mixture of produce and detritus, the grader further comprising a detritus separator, the detritus separator being operable to receive produce and detritus from the grading element and separate the detritus and produce.

2. A grader according to claim 1 further comprising a bypass element, the bypass element being disposed below the grading element, the bypass element being operable to direct produce and detritus towards the detritus separator or away from the detritus separator.

3. A grader according to claim 2 wherein the bypass element comprises a conveyor belt assembly having a conveyor belt to receive produce and detritus.

4. A grader according to claim 3 wherein the conveyor belt assembly comprises a drive operable to drive the conveyor belt in a first direction to direct the produce to the detritus separator and in a second direction to direct produce away from the detritus separator.

5. A grader according to claim 3 or claim 4 wherein the conveyor assembly is movable between a first position to direct produce to the detritus separator and a second position to direct produce away from detritus separator.

6. A grader according to any one of claims 2 to 5 wherein the bypass element is operable to direct produce away from the detritus separator and to a first receptacle.

7. A grader according to claim 6 wherein the bypass element further comprises a second conveyor belt operable to receive produce from the conveyor assembly and direct produce to the first receptacle.

8. A grader according to any one of the preceding claims wherein the detritus separator comprises a driven roller whereby produce falling on the roller is directed to a first outlet and detritus landing on the roller is directed towards a second outlet.

9. A grader according to claim 8 further comprising a brush to remove soil from the driven roller.

10. A grader according to claim 9 wherein the brush comprises a driven rotary cleaning brush.

11. A grader according to any one of claims 8 to 10 comprising a further driven roller, whereby produce falling on the further driven roller is directed towards the driven roller.

12. A grader according to any one of claims 8 to 11 wherein the first outlet comprises a first conveyor belt and the second outlet comprises a second conveyor belt.

13. A grader according to any one of the preceding claims wherein the grading element comprises a foraminous belt.

14. A grader according to any one of claims 8 to 13 where dependent directly or indirectly on claim 2 wherein the bypass element is disposed below the grading element and the detritus separator is disposed below the bypass element.

15. A grader substantially as descried herein and/or as shown in the accompanying drawings.

16. Any novel feature or novel combination of features described herein and/or in the accompanying drawings.