GB2164833A - Improvements relating to spreading machines - Google Patents

Abstract

The invention provides a machine for distributing granular and/or powdery material wherein a hopper for connection to the rear of an agricultural tractor has preferably two transverse conveyors 14, 16 located so that the material in the hopper falls onto the conveyors which traverse the bottom of the hopper. The conveyors transfer the material from the hopper outwardly and transversely of the direction of travel of the tractor to outboard spinner discs or pendulum type distributors which are located at the ends of the conveyors and distribute the material over the ground to be treated. An additional rearwardly extending conveyor 18 with associated spinner disc may be provided. <IMAGE>

Description

SPECIFICATION Improvements relating to spreading machines This invention relates to spreading machines for spreading granular and/or powdery material, such as fertilizer, natural bulk materials, slag or the like, as used in agriculture and horticulture.

Fertilizer is usually applied to an area to be treated by means of equipment carried by or attached to the rear of a tractor vehicle, which traverses the area in passes. Clearly, the wider the spread of the material at each pass, the fewer passes which have to be made over the area to completely treat all of same. There is therefore a demand for spreading equipment which can apply the spread material to a large area during each pass, for example of a width up to 36m, but there is also a need to ensure that the application is accurate so that the whole of the area will be effectively treated.

The known spreading machines used for the purpose indicated above, take various forms, and in one form, the machine comprises a hopper for containing the bulk material, and in the base of the hopper is a conveyor which runs fore and aft of the direction in which the machine is transported in use, and at the rear the conveyor leads to one or more distribution discs which, in being spun at high speed, distributes the material over the area trasversed by the machine. The use of two of such discs located side by side has the shortcoming that the material is not spread evenly on the ground, because generally speaking each of the discs has a spread width of some 6m, and therefore ideally the discs should be spaced transversely by 1 2m for even distribution.This modification has in fact been effected in another known arrangement, wherein the fore and aft conveyor leads to two transverse conveyors, at the outer ends of which the discs respectively are located.

In another known type of machine, a distribution unit is provided with a spout which in use swings pendulum like, and the material to be distributed issues from the end of the spout. The issuance of the material coupled with its back and forth swinging effects distribution of the material, but this equipment is severly limited as to the effective width which can be covered during each pass of the machine.

There are various other forms of distributor machines which provide laterally extending distribution booms, to ensure the disposition of the material over a large width, but generally speaking these machines, some of which used compressed air for feeding the material throughout the length of the boom, are expensive to maintain, and if they are not maintained, they are extremely liable to failure and breakdown, or inaccuracy of distribution of the material.

The present invention seeks to provide a spreader machine, by the design of which there can be achieved accurate distribution of material over the larger widths now being demanded, which machine is simple in construction, but significantly different in concept from the machines currently known.

In accordance with the present invention there is provided a machine for the distribution of granular and/or powdery material comprising a hopper for receiving a supply of the material to be distributed, and has one but preferably at least two conveying reach or reaches which extend transversely to the direction in which the machine is to be moved in use, said conveying reaches being located to traverse the base of the hopper to receive material directly therefrom, and at their outer ends, the reach or each of said reaches being provided with a material distribution unit, such as a spinner disc unit or a pendulum distributor unit.

The said two or more reaches are preferably defined by individual conveyors which are arranged in spaced horizontal planes and which overlap in the base of the hopper.

Various embodiments of the machine may be provided. For example the machine may be adapted to be mounted directly to the three point hitch of an agricultural tractor, or it may be provided with its own wheeled chassis so as to be trailed behind a tractor, and power for the conveyors may be provided by the power take off from the traction vehicle, from a ground engaging wheel or the machine may have its own power unit.

A number of different conveyor arrangements are possible, depending upon the area to be treated. For example, if the machine is to treat a 1 2m width at each pass, then there may be two conveyors extending to the respective sides of the hopper through a distance of 3m, and at the end of each conveyor may be a spinner disc having a distribution width of 6m. For an 18m distribution, the said two conveyors may extend to a lateral distance of 6m, whilst a third conveyor extending in the fore and aft direction of the machine may be provided at the rear of the machine, and at the rear end of such conveyor would be a third spinner disc.To provide for distribution of 24m, there may be two conveyors extending from each side of the hopper, and of the conveyors at each side, one extends to a distance of 3m, and the other extends to a distance of 9m from the side of the hopper, and again spinner discs would be provided on the ends of all conveyors.

The bottom of the hopper may simply be open to allow the material to fall from the hopper on to the conveyors for the distribution of the material, or the base of the hopper may have channels for receiving the conveyors.

The conveyors can be rubber belt conveyors or flighted chain conveyors.

The rate of discharge of each conveyor may be controlled as is known by regulating a trap door or "sluice gate" immediately above the conveyor, and also the speed of the conveyor is changed to suit the application rate. It is likely that the distributor discs will be arranged to run at a constant speed to achieve the desired spread width.

The rate of discharge can be controlled in relation to the forward speed by the conveyors being powered from ground engaging wheels or in an alternative, especially on the smaller machines by the rear wheels of the carrying tractor. The discharge rate may be controlled independently of forward speed, in which the case the conveyors would be powered from the tractor's hydraulic or power take off drive.

The simplicity of the concept provides a major advantage. The conveyors are located directly under the hopper cavity which is such as to allow the material to fall directly onto the conveyors, and in the concept of the invention it is not necessary to have a rearwardly travelling conveyor, although one may be provided in the 18m spread machine.

The accompanying diagrammatic drawings illustrate diagrammatically the various possibilities which are envisaged for 12m, and 18m and a 24m respectively in Figs. 1, 2 and 3, whilst Figs. 4 and 5 show an end view of the hopper of Fig. 1.

In each of these Figures, the direction of travel of the machine is indicated by the arrow 10, and the hopper by 12. In the arrangement of Fig. 1, the 12m machine, the two conveyors are indicated by numerals 14 and 16, each with its own distributor disc 14A and 16A. The direction of travel of the upper reaches of the respective conveyors is indicated by arrows 14B and 16B.

In the Fig. 2 arrangement, the 18m machine, the conveyors 14 and 16 are longer, and in addition there is a third conveyor 18 which extends fore and aft of the machine and at the rear end is a distributor disc 18A.

The upper reach of conveyor 18 travels in the direction indicated by reference 18B.

In the arrangement of Fig. 3, the 24m machine, four conveyors 14, 16, 20 and 22 are provided which extend laterally from the respective sides of the hopper, and each is provided with its own distributor disc.

By the use of laterally extending conveyors a wide and even spread of the material can be achieved, making the machine suitable for use in the system which is known as "tramlining" whereby tracks are left through the crop and these tracks are driven down each time the various materials are to be applied.

The outwardly extending conveyors 14, 16, 20 and 22 may be adapted to be folded to an out of use position along hinges indicated by the numeral 26, for the transportation of the machine.

Referring to Figs. 4 and 5, the hopper is shown in end view and in sectional side view for the two conveyor arrangement shown in Fig. 1. As shown in Fig. 5, there are two wells 50, 52 for locating the respective conveyors 14 and 16, the said wells 50 and 52 extending for the length of the hopper. As shown in Fig. 4, to the outside of the hopper and at the end thereof (in the region of the conveyor hinge 26) is the control gate 54 whose position can be controlled by means of a handle and screw arrangement 56, 58, for controlling the amount of material carried by the conveyor 16 to its spinner disc. There is a similar arrangement at the other end of the hopper for controlling the discharge material by conveyor 14.

These conveyors in fact may be parallel to the bottom of the hopper or inclined upwards (or downwards) at the outer ends of the hopper so that the spinning or reciprocating distribution mechanism on the end of the hopper is in fact higher than the hopper for spreading in growing crops.

It is not necessay for conveyors to overlap each other, and they could both run into the hopper towards each other in alignment but with their inner ends spaced by at a distance sufficient to enable the chain to fill with fertiliser from the hopper.

In addition the conveyor mechanisms that protrude to either side would be of varying lengths to cope with different spread widths, and these discharge conveyor mechanisms would be so arranged so that they could be folded either vertically or horizontally to pass through gates and travel on the highway and so on.

In a modified concept of Fig. 4 there is a control means at the base of the hopper which controls the feed of the material from the base of the hopper cavity and onto the conveyor reach or reaches, when the hopper can be provided with transverse conveyors as described in relation to Figs. 1 to 5.

In one example, the control means is a simple horizontal trap door or sluice gate arrangement, which may be power driven or manually operable, whilst in an alternative arrangement there is a rotary metering mechanism between the bottom of the hopper cavity and the conveyor reach or reaches. Again, the rotary metering mechanism may be power driven or manually operable.

The material still falls essentially directly from the bottom of the hopper cavity onto the reach or reaches, but the amount which falls or the rate at which it falls can be controlled by the above mentioned control means.

The accompanying diagrammatic drawing Fig. 6 illustrates an improved concept as applied to tractor mounted spreader unit having a fore and aft distributor conveyor such as conveyor 18 leading to a spinner disc such as disc 18.

Referring to Fig. 6, the tractor spreader unit comprises a hopper 100 of downwardly tapering width leading to a front to rear distributor conveyor 120, under the discharge end of which is mounted a spreader disc 140, all of which is of conventional construction. The unit is mounted on a tractor at the rear end of which only one rear wheel 160 is shown, the mounting being any suitable means such as the three point linkage of the tractor. The drive to the conveyor 120 is via the tractor wheel 160, by means of a sprocket 180 fast with the tractor and on its axis, a chain 200 and a driven sprocket 220, chain 200 being trained round the sprockets 180 and 220. The sprocket 220 is supported for rotation by a telescopable arm 240 and a telescopic drive shaft 260 drivingly couples the sprocket 22 via universal joints 280 and 300 to a pulley 320 which drives a second pulley 340 via belt 360.Pulley 340 connects via drive shaft 380 with the sprocket 400 around which the conveyor 120 is trained and by which the conveyor 120 is driven.

The adjustability of the support arm 240 and the drive shaft 260 is sufficient to cater for the known range of tractor sizes and tyre sizes for tractor rear wheels so that the unit can be mounted on any tractor using any known tyre size.

It is known to mount spreading units on the rear of agricultural tractors, and it is also known for the effective distribution of the spreading of fertilizers for farmers to create "tramlines" in the crop, and to use such tramlines, which are lines in which no crop is growing, for the traversing of the area to be fertilised by having the tractor wheels run in the tramlines. Whilst it is recommended that the tramline pitching over any particular area is standardised, in practice the spacing of pairs of tramlines and the pitching of tramlines varies considerably. This may arise due to the fact that different tractors have different wheel spacing, or different tractors use at least on the rear wheels tyres of different widths.

The arrangement of Fig. 6 describes the mounting of a spreader unit on an agricultural tractor which has the capability of being adapted to suit tractors having different rear wheel spacing and having tyres of different widths.

The feature of advantage of the Fig. 6 unit is that the drive of the front to rear conveyor leading to the rear spreader disc is taken from the tractor wheel, and the transmission from the tractor wheel to the front to rear conveyor is length adjustable, enabling the unit to be used with tractors of different rear wheel spacing and/or tractors having tyres of different widths.

Claims (8)

1. A machine for the distribution of granular and/or powdery material comprising a hopper for receiving a supply of the material to be distributed, and has one but preferably at least two conveying reach or reaches which extend transversely to the direction in which the machine is to be moved in use, said conveying reaches being located to traverse the base of the hopper to receive material directly therefrom, and at their outer ends, the reach or each of said reaches being provided with a material distribution unit, such as a spinner disc unit or a pendulum distributor unit.

2. A machine according to claim 1, wherein there are two of said conveying reaches and a third conveyor reach extending for and aft of the machine leading to a third distributor located to the rear of the machine.

3. A machine according to claim 1 or 2, wherein the or each conveyor reach is adapted to be driven by a transmission from a ground engaging wheel.

4. A machine according to any preceding claim wherein the or each transverse conveyor reach is associated with a metering means controlling the amount of material fed by the conveyor reach to its distributor unit.

5. A machine according to claim 4, wherein the metering means comprises an adjustable gate on the hopper end.

6. A machine according to claim 4, wherein the metering means comprises a rotary metering device in the hopper.

7. A machine according to any preceding claim, wherein there are four of said transverse conveyor reaches two extending to each side of the hopper.

8. A machine for the distribution of granular and/or powdery material substantially as hereinbefore described with reference to any of the embodiments described herein with reference to the accompanying drawings.