GB2290612A

GB2290612A - Beet sampler

Info

Publication number: GB2290612A
Application number: GB9410394A
Authority: GB
Inventors: Geoffrey Ashley Greenwood
Original assignee: COCKSEDGE ENG Ltd
Current assignee: COCKSEDGE ENG Ltd
Priority date: 1994-05-24
Filing date: 1994-05-24
Publication date: 1996-01-03
Anticipated expiration: 2014-05-24
Also published as: GB2290612B; GB9410394D0

Abstract

Beet sampling apparatus has a rotatable sampling tube (7) which at its lower end has axially movable pick-up scoops or flights (8) which cooperate with the lower end of the tube in the closed condition, wherein the sampling tube is provided with readily replaceable flight guides (54) for guiding the flights into their correct location relative to the sampling tube when the flights are retracted to the closed condition from an open beet-releasing condition. The scoops are carried on support rods. Apparatus is typically supported on a movable carriage (5) operated above beet delivery lorries from which beet samples are taken. <IMAGE>

Description

Beet Sampling Apparatus This invention relates to beet sampling apparatus.

When sugar beet is delivered to a factory for processing, it is typical practice, when the beet carrying vehicle enters the factory premises, to take a sample of the beet being carried to enable testing for dirt tare and sugar content. The payment made to any particular grower depends on the sugar and dirt content of the beet which that grower has delivered to the factory.

Apparatus for extracting a sample from a beet carrying vehicle is known from U.K. Patent Specification No.

1 525 241. The apparatus described in this document extracts a core sample by driving a sampling tube down to the floor of the vehicle, as this is considered to provide a fair basis for subsequent assessment of sugar and dirt content.

In the known apparatus, as also in the apparatus in accordance with the present invention, the sampling tube carries scoops, hereinafter referred to as flights, at its lower end. The tube is rotated during descent through the beet so that the flights scoop the beet up into the tube. Following upward retraction of the tube containing the core sample, the flights are opened to allow the core sample to discharge into a suitable collector. In practice opening the flights is effected by moving them downwards away from the open bottom end of the sampling tube, for which purpose the flights are mounted at the lower ends of supporting rods which descend through guides mounted within the tube.

When the core sample has discharged, the flights are retracted upwardly again to cooperate with the lower end of the sampling tube in the manner necessary for extraction of the next sample.

It will be understood, however, that the sampling tube is operating under extremely adverse conditions, as the beet being sampled is liable to be wet and dirty and be associated with various extraneous matter including stones. The parts are therefore subject to heavy wear.

Consequently, in use of the known apparatus, it has been found that the flights, when retracted upwardly from the open position, can fail to locate correctly relative to the lower end of the sampling tube, at worst leading to a jammed condition and at least impairing the efficiency of extraction of a subsequent core sample. One object of the present invention is to provide a solution to this problem.

Thus according to one aspect of the present invention, there is provided beet sampling apparatus having a rotatable sampling tube supporting axially movable flights cooperating with the lower end of the tube in the closed condition, wherein the sampling tube is provided at its lower end with flight guide and locating means, which guide the flight into correct location relative to the lower end of the sampling tube when the flights are retracted to a closed condition from an open condition for releasing a core sample.

The sampling tube remains subject to heavy wear in use, but in practice this is primarily taken by the flight guide and locating means, which are therefore preferably made to be readily replaceable. The flight guide and locating means therefore preferably bolts in position at the lower end of the sampling tube.

Although the aforesaid flight guide and locating means is fitted to the bottom of the sampling tube, it is nevertheless important, both to ensure correct cooperation between the flights and the sampling tube and to reduce wear, for the flight support rods to be accurately mounted and accurately guided for axial movement within the sampling tube when the flights are to be opened (lowered) and closed (raised).

The axial movement of the flights is conveniently produced by a small cylinder, typically a hydraulic cylinder, located just above the top of a gearbox through which the sampling tube is driven in rotation.

Accordingly, near the top of the sampling tube and within it, the flight support rods are secured to a mounting plate itself mounted for rotation when the sampling tube is rotated, as well as to be lowered and raised relative to the sampling tube by the above-mentioned hydraulic cylinder, and below the mounting plate the support rods pass through fairleads which secure to the inside wall of the sampling tube.

Preferably, at least one fairlead for each flight support rod is provided towards the bottom of the sampling tube, and at least one at a substantially higher position.

A preferred fairlead is machined of hard plastics material with a curved outer face precisely matching the inside curvature of the sampling tube, so that the fairlead seats precisely against the inside wall of the sampling tube when secured thereto by suitable fixing screws, thus accurately locating an aperture in the fairlead through which the flight support rod extends. When the sampling tube is driven in rotation for taking a sample as the tube descends through the beet, the fairleads serve as a coupling whereby the flight support rods, and thus the mounting plate to which the rods are secured, are driven in rotation with the tube.

As in the closed position the flights are required to locate accurately to the bottom of the sampling tube, it is preferable for the mounting plate for the flight support rods, which plate is located near the top of the tube, to be able to tilt to a very limited extent to accommodate manufacturing and fitting tolerances.

Preferably, therefore, the mounting plate forms part of a sub-assembly which is rotatable, relative to a rotationally fixed central shaft supporting the assembly for vertical movement, on a spherical bearing. This spherical bearing permits limited tilting movement of the sub-assembly about a horizontal axis, whilst enabling free rotation of the sub-assembly on the spherical bearing under the rotational drive imparted to the sub-assembly from the flight support rods extending through the fairleads.

Just above the above-described sub-assembly, the sampling tube is closed by a top plate forming part of a second sub-assembly drivable in rotation from a driving sleeve itself driven by a motor, conveniently an electric motor.

The said driving sleeve surrounds the afore-mentioned rotationally fast shaft on which the flight support rod assembly is carried for vertical movement relative to the sampling tube.

Notwithstanding the afore-mentioned measures to reduce wear and tear, it is occasionally necessary in use of the equipment to remove the sampling tube for maintenance or to replace it. Accordingly, the second sub-assembly supporting the sampling tube is preferably clamped to the driving sleeve by means of a shrink coupling.

All the parts of the apparatus above-described are carried by a vertical movable carriage which drives the sampling tube down through the beet and then retracts the sampling tube containing the core sample upwardly. The vertical carriage is in turn supported on a horizontal carriage which transfers the sampling tube to a sample dispensing position.

When a sample is being taken, it is important for the sampling tube to be driven down to the floor of the vehicle carrying the beet and means are provided for sensing arrival of the tube at the floor of the vehicle and initiating upward retraction of the sampling tube when contact is sensed.

Such sensing may be carried out by the manually set depth control system described in U.K. Patent Specification No.

1 525 241, but preferably a fully automatic sensing system is employed additionally or instead, wherein the sampling tube is provided with pressure shoes which sense increase in pressure in a hydraulic drive circuit due to contact with the floor of the vehicle, and signal a hydraulic circuit control cylinder to reverse the sense of vertical drive to the vertically movable carriage.

Still another feature of the present invention concerns the horizontal carriage which moves the above-described equipment between a sampling position over a vehicle entering the beet processing factory and a sample discharge position. The carriage has pairs of front and rear wheels which run on rails on a gantry extending over the road through which vehicles enter the factory.

In accordance with this further feature of the invention, the horizontal carriage has an idler shaft for one of its two pairs of wheels, the idler shaft having an eccentric stub at least at one end on which one of the wheels is mounted, whereby the carriage automatically makes four wheel contact with the rails on which it runs. In this connection, it will be appreciated that stability of the horizontal carriage is essential to efficient operation of the sampling equipment mounted on the carriage, and contributes substantially to reduced wear of the parts incorporated in the equipment.

Beet sampling apparatus in accordance with the invention is now exemplified with reference to the accompanying drawings, in which: Figure 1 is a perspective view of the complete apparatus; Figure 1A shows a detail; Figure 2 shows an idler shaft for the horizontal carriage of Figure 1; Figure 3 shows a mounting arrangement for the sampling tube of Figure 1; Figure 4 shows a mounting arrangement within the sampling tube for flight support rods; Figure 5 shows a fairlead for a flight support rod; Figures 6 and 6A show details of one of the flights at the lower end of the sampling tube; and Figures 7 and 7A show details of a flight guide and locating member mounted to the lower end of the sampling tube.

Referring first to Figure 1, a horizontal carriage 5 having a drive means 9 powered from a hydraulic power supply 10 is movable back and forth along rails which are carried by a gantry (not shown) extending over a road along which a beet delivery lorry enters a processing factory.

In order to extract from the lorry a sample of beet to be tested for dirt and sugar content, the carriage 5 is positioned above the vehicle to enable a vertical carriage 2 to be operated by a drive cylinder 1, thereby to drive a rotating sampling tube 7 down through the beet so that tube entry flights 8 at the lower end of the sampling tube scoop a core sample into and up into the interior of the tube. Reference 6 denotes a tube tilt safety guide and reference 4 indicates a hydraulic drive motor for driving the sampling tube 7 in rotation during its descent on the vertical carriage.

Having taken a core sample, rotation of the sampling tube 7 is stopped and the vertical carriage 2 is raised. The horizontal carriage 5 is then moved to a discharge position over the side of the road, where the sample is collected for testing. Discharge is effected by opening the flights 8, which is achieved by downward movement of the flights away from the lower end of the sampling tube 7, as shown in Figure 1A. For this purpose, the flights 8 are carried at the bottom ends of support rods mounted within the sampling tube to rotate with said tube. The support rods can be raised and lowered by a hydraulic cylinder 3.

Precise positioning of the flights 8 at the lower end of the sampling tube 7 is essential to efficient operation.

However, owing to the extremely adverse environment in which the sampling equipment is operating, heavy wear of various parts of the equipment occurs, and it has proved difficult repeatedly accurately to locate the flights 8 relative to the lower end of the sampling tube 7 when the support rods are raised to return the flights to the closed position, as a result of which jamming has sometimes occurred. A principal aim of the invention is to provide a solution to this problem. However, various factors play a part in contribution to wear and tear, ease of maintenance and the replacement of the minimum number of parts when wear has occurred to an unacceptable extent.

It is therefore a secondary object of the invention also to provide solutions to problems which contribute generally to wear and tear and to ease of maintenance.

First, therefore, reference is made to the horizontal carriage 5 of Figure 1. This carriage has four wheels with band flanged tyres mounted on fore and aft shafts, one a driving shaft and one an idler shaft.

The idler shaft 12 is shown in Figure 2. This shaft 12 is formed with eccentric stubs 14, 14A fixed thereto at its ends, and the tyred wheels are mounted on these eccentric stubs. In this way, without resorting to a complex suspension system, it is ensured that all four wheels seat firmly on the rails, and good stability of the carriage is thereby achieved.

Reference is now made to Figure 3, which shows the mounting of the sampling tube on the vertical carriage 2 of Figure 1. The sleeve 16 forms a part of the carriage, and is drivable in rotation by the motor 4 of Figure 1.

Shaft 18 extending downwardly through the sleeve 16 does not rotate, but is vertically movable by the hydraulic cylinder 3 of Figure 1 in order to open and close the flights, as will become clear from later description.

The top of the sampling tube 7 is provided with a subassembly 20, including a top plate 21 to which the tubular part 7 is welded, which assembly clamps to the sleeve 16 by means of a shrink coupling 22. Circlip 24 holds the sampling tube 7 in position while the shrink coupling is being tightened. Reference 26 denotes a bearing provided between the sleeve 16 which rotates and the shaft 18 which is vertically movable through the sleeve and sub-assembly 20. Below the top plate 21, the shaft 18 carries a second sub-assembly 28 which constitutes a mounting means for the support rods which carry the flights at the bottom end of the sampling tube. These rods are not shown in Figure 3.

In prolonged use of the sampling equipment over many years in an adverse environment, it is almost inevitable that the sampling tube assembly will require replacement. The shrink coupling facilitates this replacement, as it is much less likely than other forms of clamping to corrode and become substantially unreleasable.

The sub-assembly 28 of Figure 3 is shown in detail in Figure 4. A mounting plate 30 has apertures 32 at which the upper ends of the flight support rods (not shown) are fixed in position. This plate is welded to a cylindrical member 34 rotatable on a spherical bearing 36. Additionally to this rotation, however, the spherical bearing 36 accommodates very small tilting of the mounting plate 30, as necessary to accommodate manufacturing and fitting tolerances when the support rods, carrying the flights at their lower ends, are secured in position, having due regard to the requirement to ensure accurate positional engagement between the flights and the lower end of the sampling tube not only initially but each time the flights are raised from the open discharge position to the closed position for sampling.

Referring now to Figure 5, there is shown a fairlead 38 for the flight support rods. This two part element has an outer face 40 curved precisely to match the internal curvature of the sampling tube. Accurate matching is ensured by making the two part fairlead 38 of a machinable hard plastics material. A number of fairleads 38 are secured in position to the inside wall of the sampling tube and serve as guides for vertical movement of the flight support rods when the flights are opened and closed.

Reference 42 denotes an aperture in the fairlead 38 through which the flight support rod passes.

Most importantly, however, the fairleads 38, which rotate with the sampling tube when the latter is driven in rotation, also cause the flight support rods to rotate with the sampling tube. This rotation is enabled by the sub-assembly 28 of Figure 4, as the mounting plate 30 to which the support rods are secured is freely rotatable on the spherical bearing 36.

Turning now to Figures 6 and 6A, there is shown one of the flights 44 provided at the lower end of the sampling tube. As is apparent from Figure 1 two such flights are provided, identical with one another, and each carried by a pair of support rods, so that four support rods are provided in all.

Each flight 44 essentially consists of a vertical leg 46 and a scoop-shaped plate 48. The overall form of the flight 44 is such that, as the sampling tube and flights rotate during descent through the beet in the vehicle, a beet sample is forced into and up inside the sampling tube to form a core therein, released only when the flights are opened.

The two support rods supporting the flight connect to the flight one through the vertical leg 46, as indicated by the rod-receiving aperture 50, and one connects to a slot in the shaped plate 48, as indicated at 52.

It has been mentioned that the flights are required accurately to cooperate with the bottom end of the sampling tube, not only initially but each time the flights are returned to the closed position. To this end, a flight guide and locating means is provided at the lower end of the sampling tube. A member 54 constituting said guide and locating means is shown in Figures 7 and 7A.

One such member is provided for each flight.

Each guide and locating member 54 comprises a curved guide and locator 56 for an edge of the flight and a curved flange 58 by means of which the member bolts to the lower end of the sampling tube, as indicated by bolt holes 60.

Securing the guide and locating member 54 by means of bolts enables this member to be readily replaced when necessary due to wear and tear.

Primarily, tapered edge face 62 of the guide member guides and locates the flight as it completes its vertical movement into the closed position.

Although not illustrated, a final feature of the beet sampling apparatus which should be mentioned is that the core sample of beet is preferably taken right down to the floor of the beet-carrying vehicle. It is thus necessary, for avoidance of damage, to reverse the vertical movement of the vertical carriage 2 of Figure 1 immediately the floor is reached on descent. One method of achieving this is to provide a hydraulic pressure sensing shoe on the bottom of the sampling tube, which signals the carriage drive motor to reverse the sense of vertical drive immediately a predetermined increase in pressure value is detected.

It will be appreciated that various modifications of the above described and illustrated arrangement of beet sampling apparatus are possible within the scope of the invention.

Claims

1. Beet sampling apparatus having a rotatable sampling tube supporting axially movable flights cooperating with the lower end of the tube in the closed condition, wherein the sampling tube is provided at its lower end with flight guide and locating means, which guide the flight into correct location relative to the lower end of the sampling tube when the flights are retracted to a closed condition from an open condition for releasing a core sample.

2. Beet sampling apparatus according to claim 1, wherein the flight guide and locating means are mounted so as to be readily replaceable.

3. Beet sampling apparatus according to claim 2, wherein the flight guide and locating means bolts in position at the lower end of the sampling tube.

4. Beet sampling apparatus according to any of claims 1 to 3, wherein axial movement of the flights is produced by a driving cylinder located just above the top of a gearbox through which the sampling tube is driven in rotation.

5. Beet sampling apparatus according to claim 4, wherein the cylinder is a hydraulic cylinder.

6. Beet sampling apparatus according to claim 4 or claim 5, wherein, near the top of the sampling tube and within it, the flight support rods are secured to a mounting plate itself mounted for rotation when the sampling tube is rotated, as well as to be lowered and raised relative to the sampling tube by the said cylinder, and below the mounting plate flight support rods pass through fairleads which secure to the inside wall of the sampling tube.

7. Beet sampling apparatus according to claim 6, wherein at least one fairlead for each flight support rod is provided towards the bottom of the sampling tube, and at least one at a substantially higher position.

8. Beet sampling apparatus according to claim 6 or claim 7, wherein each fairlead is machined of hard plastics material with a curved outer face precisely matching the inside curvature of the sampling tube, so that the fairlead seats precisely against the inside wall of the sampling tube when secured thereto by suitable fixing screws, thus accurately locating an aperture in the fairlead through which the flight support rod extends.

9. Beet sampling apparatus according to claim 6 or claim 7 or claim 8, wherein, when the sampling tube is driven in rotation for taking a sample as the tube descends through the beet, the fairleads serve as a coupling whereby the flight support rods, and thus the mounting plate to which the rods are secured, are driven in rotation with the tube.

10. Beet sampling apparatus according to any of claims 6 to 9, wherein the mounting plate for the flight support rods, which plate is located near the top of the tube, is able to tilt to a very limited extent to accommodate manufacturing and fitting tolerances.

11. Beet sampling apparatus according to claim 10, wherein the mounting plate forms part of a sub-assembly which is rotatable, relative to a rotationally fixed central shaft supporting the assembly for vertical movement, on a spherical bearing.

12. Beet sampling apparatus according to claim 11, wherein, above and adjacent the said sub-assembly, the sampling tube is closed by a top plate forming part of a second subassembly drivable in rotation from a driving sleeve itself driven by a motor.

13. Beet sampling apparatus according to claim 12, wherein the motor is an electric motor.

14. Beet sampling apparatus according to claim 12 or claim 13, wherein the said driving sleeve surrounds the said rotationally fast shaft on which the flight support rod assembly is carried for vertical movement relative to the sampling tube.

15. Beet sampling apparatus according to claim 14, wherein the second sub-assembly supporting the sampling tube is clamped to the driving sleeve by means of a shrink coupling.

16. Beet sampling apparatus according to any of claims 1 to 15, wherein the sampling tube and parts associated therewith are carried by a vertical movable carriage which drives the sampling tube down through the beet and then retracts the sampling tube containing the core sample upwardly

17. Beet sampling apparatus according to claim 16, wherein the vertical carriage is in turn supported on a horizontal carriage which transfers the sampling tube to a sample dispensing position.

18. Beet sampling apparatus according to claim 16 or claim 17, wherein an automatic sensing system is provided for sensing arrival of the sampling tube at the floor beneath the beet.

19. Beet sampling apparatus according to claim 18, wherein the sampling tube is provided with pressure shoes which sense increase in pressure in a hydraulic drive circuit due to contact with the floor, and signal a hydraulic circuit control cylinder to reverse the sense of vertical drive to the vertically movable carriage.

20. Beet sampling apparatus according to any of claims 17 to 19, wherein the horizontal carriage, which moves the sampling means between a sampling position over a vehicle entering a beet processing factory and a sample discharge position, has pairs of front and rear wheels which run on rails on a gantry extending over the road through which vehicles enter the factory.

21. Beet sampling apparatus according to claim 20, wherein the horizontal carriage has an idler shaft for one of its two pairs of wheels, the idler shaft having an eccentric stub at least at one end on which one of the wheels is mounted, whereby the carriage automatically makes four wheel contact with the rails on which it runs.

22. Beet sampling apparatus substantially as hereinbefore described with reference to the accompanying drawings.