GB1604852A - Agricultural implements - Google Patents

Description

(54) IMPROVEMENTS IN OR RELATING TO AGRICULTURAL IMPLEMENTS (71) We, CRAVEN TASKS ENDOVER) Lv D, a Company registered under the laws of England, of Anna Valley, Andover, Hampshire SP11 7NF, England, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to agricultural implements such as fertiliser spreaders.

Chemical fertilisers and other chemicals are an essential requirement in modern inorganic agriculture. Chemical fertilisers may be applied in several forms and it is found ta be particularly convenient to apply them before and during sowing of plants and during their growth.

Until recently such granular fertilisers were only applied up to the early stages of crop growth but it has been found as a result of research that the fertilisers may be used more economically by applying them at regular intervals throughout the crop growth period, and that crop quality may be improved by the application of fertilisers right up to the final stages af the growth. This particularly applies to cereal crops such as barley and wheat.

Difficulties have been experienced in the application of chemical fertilisers during the late stages in crop growth because the wheeled vehicles such as tractors and trailed fertiliser spreaders of conventional design have tended to damage the crops with consequential loss of yield To minimise such damage a system called tramlining has been introduced when, during the drilling of the seeds, two single rows of seeds are omitted to correspond with the trick of a specified agricultural tractor.

These to missed rows are known as tram- lines and provide spaced in the crop through which the wheels of the tractor may subsequently pass without damaging the growing crop even up to the last stages of the crop growth.

It is an object of the present invention to provide a spreader which is particularly suit- able for "tramline" use and which alleviates these difficulties.

Accordingly the present invention pro- vides an agricultural spreader arranged ta be trailed behind a tractor vehicle ,having a wheeled chassis comptising or supporting ar container for material to be spread and arranged to be trailed over the ground, in which the chassis is provided with two spaced land wheels and pivotally connected to a towing frame about a vertical pivotal axis arranged to be approximately mway between the rear axle of the tractor vehicle and the axis of the two land wheels, ti tow ing frame being attached in use to the tractor vehicle.

m order to promote a fuller understanding of the above, and other aspects of tltlr pre; sent invention an embodiment will not be described, by way of example only, with reference to the accompanying drawings in which; Figure 1 shows a schematic perspective view af a fertiliser spreader from a rear/ view point, and Figure 2 shows the spreader of Figure I from a front/side view point.

The fertiliser spreader shown in the drawings embodying the invention comprises a chassis 10 carried on independent axles having respective wheels II, to be trailed across the ground behind a tractor vehicle. The chassis 10 is provided at its forward ertit, with towing brackets 12 which are connected with a pivotal connection about a vertical axis 13 to a towing bracket 14 which is adapted for three point Inounting ow tlte tractor by means of taunting points IS.

The towing bracket 14 and the axis 13 are preferably so arranged, relative to a pst- ticular towing tractor, that the axis 13 i mid-way between the rear axle of thc trac- tor and the axle of the wheels 11, so that in use the wheels 11 faithfully follow the paths of the rear wheels of the tractor. In this way the wheels 11 will follow in the tramlines left during sowing for the tractor wheels. The towing brackets 12 and/or the bracket 14 may be made adjustable to achieve this geometry for various tractor vehicles. The chassis 10 carries a hopper 20 which is of conventional design per se and arranged with a top surface through which it can be loaded with granular fertilisen A metering elevator 21 is positioned in the hopper towards the rear of the hopper to carry granular fertiliser from the bottom of the hopper to a point 22 is vertically above a spinning disc distributor device 23 which is of known design per se being mounted on the chassis 10 and driven by a hydraulic motor.

The elevator 21 comprises a continuous loop chain 24 which extends between a lower sprocket 25 positioned beneath the bottom of the hopper 20, and an upper sprocket 26 positioned at the point 22. The chain 24 is driven to circulate by a suitable transmission mechanism indicated generally at 27 from one of the wheels 11, so that the chain is driven as the spreader is trailed across the ground.

The transmission 27 includes a chain drive 28 from the one wheel 11 to a crossshaft 29, a chain drive 30 from the crossshaft 29 to a second cross-shaft 31, and a belt drive 32 from the second cross-shaft 31 to the chain sprocket 26. The sprockets of the chain drive 30 and the pulleys of the belt drive 32 may be changed to vary the overall drive ratio of the transmission from the wheel 11 to the chain sprocket 26, the chain and belt drives respectively being provided with suitably adjustable tensioning means 33 and 34 to enable the drives to accommodate large variations in sprocket and pulley sizes. At a suitable point in the transmission from the one wheel 11 to the sprocket 26, a one-way clutch mechanism is provided so that no drive is transmitted to the elevator when the spreader moves over the ground in reverse.

The chain 24 passes, at least in its upward moving part between the sprockets 25 and 26 through an enclosed passage 35, and the chain is fitted at spaced intervals over its entire length with paddles 36 which have a running clearance in the passage 35. The passage 35 is open to the bottom of the hopper 20 so as the chain is driven, the paddles 36 collect fertiliser falling into the passage and carry it up out of the hopper 20 up through the passage 35 to the point 22, in metered quantities which are dependent upon the size of the tubular passage and the spacing between the paddles along the chain.

The spinning disc device 23 which is preferably driven by a means of hydraulic motor 37 supplied by way of pipes 43 with hydraulic fluid under pressure from the tractor vehicle, but which may be driven by any other suitable means; is mounted in this embodiment on the chassis 10 to be slidably adjustable in a vertical direction on a pillar 38 to a height to suit the existing crop conditions. The pillar 38 is provided with a series of spaced holes 39, and the spinning disc device is carried on a frame 40 including a removable pin 41 arranged to engage in a selected one of the holes 39. An extendable chute indicated at 42 in the form of a plastics material corrugated pipe, is provided between the elevator 21 and the spinning disc device 23 to collect fertiliser granules falling out of the elevator as the chain and paddles pass over the sprocket 26, and to convey them to a feed nozzle disposed above the disc of the drive 23, in a known manner per Se.

In order to promote easy cleaning and repair, the complete elevator assembly 21 is mounted so as to be removable from the hopper and chassis. The elevator may by adjustment of the drive ratio of the transmission to it, be arranged to feed fertiliser over a wide range of feed rates so that small quantities of concentrated fertiliser, or large quantities of comparatively low concentration fertiliser may be applied. In order to assist in the satisfactory feeding of larger quantities of fertiliser materials at a high rate to the disc of the device 23, the feed outlet nozzle to the spreader device 23, at the end of the chute 42 may be bifurcated, and arranged to feed the fertiliser through two apertures disposed at spaced points above the disc of the device. This assists in the feeding of fertiliser satisfactorily to the disc at the high flow rate while still maintaining accurate spread pattern.

The transmission between the wheels 11 and the chain of the elevator 21 is as mentioned arranged to provide variable ratio by which the distance moved by the chain of the elevator and thus the quantity of fertiliser elevated by it, is related to the rotation of the wheels 11 and thus the distance travelled over the ground by the spreader. By presetting the drive ratio the quantity of fertiliser distributed over a given area of field traversed by the spreader can be adjusted to meet the requirements of crop and fertiliser conditions.

The drive to the elevator is preferably interlocked by hydraulic means with the device 23, so that the elevator is only driven by the wheels 11 when the spinning disc of the device is operating, thus to avoid accumulation of fertiliser in the chute 42.

The track of the wheels 11 on the chassis 10 is variable so that it can be adjusted to suit a particular tramline spacing corresponding to the track of the towing tractor.

Thus it can be seen that a fertiliser spreader is provided in which the spreading unit can be easily adjusted in height, while maintaining the centre of mass of the spreader at a constant low height, offering particular suitability for treatment of growing crops.

Some variations in the design, not shown in the drawings, are possible to meet particular requirements in a spreader, particularly when it is desired to handle very high rates of material distribution or to control the rate and distribution pattern with particular accuracy over a range of height adjustment.

Instead of a single spinning disc being provided, for high rates of distribution, two spinning discs may be provided each mounted on the device in a similar manner to the single disc discussed above, and fed by the bifurcated version of the extendable chute.

Instead of a single chute being provided the outlet at the top of the elevator may be divided or bifurcated into a plurality of outlets and a respective chute similar to that described above provided for each of that plurality of outlets to feed material either to respective points on a singde disc; or to a respective disc, each of which is again mounted on the device in a similar manner to the single disc discussed above. It is anticipated that two such discs with respective chutes will meet most requirements, but more than two may be used to meet particular needs.

In a further arrangement, instead of the outlet of the metering conveyor being divided, two separate conveyers may be provided, each with a respective chute, feeding a respective spinning disc device.

In cases where particular accuracy in feed rate and pattern is needed, to compensate for the different characteristics which may be caused in feeding some materials by the variation in vertical drop of material from the metering elevator onto the spinning disc, it may be arranged that this drop is maintained constant over the range of height adjustment.

This may be achieved by making the outlet point from the metering elevator adjustable along the slant height of the elevator so that as the spinnning disc is raised, the outlet is also raised to maintain the drop constant. In such an arrangement the mounting of the spinning disc device may be such that during height adjustment, the fore and aft displacement to match that of the elevator outlet is achieved. One manner in which this can be done is to incline the support 38 to match the inclination of the elevator.

An alternative manner in which the drop from the elevator outlet to the spinning disc may be maintained constant, is to mount the elevator pivotally at or adjacent its lower end in the hopper; so that, as the spinning disc is adjusted in height, the elevator may be pivoted to maintain the drop constant.

Again fore and aft compensation for the spinning disc may be provided.

While the above discussion has been in respect of a fertiliser spreader for agricultural use, it will be appreciated that the spreader of the invention can also be used for spreading other powdered or granular materials and in other than agricultural applications, for instance in spreading salt and sand mixture on public highways.

Attention is drawn to our co-pending application No. 27492/77 (Serial No. 1604851) from which this application was divided.

WHAT WE CLATM IS:- 1. An agricultural spreader arranged to be trailed behind a tractor vehicle, having a wheeled chassis comprising or supporting a container for material to be spread and arranged to be trailed over the ground, in which the chassis is provided with two spaced land wheels and pivotally connected to a towing frame about a vertical pivotal axis arranged to be approximately mid-way between the rear axle of the tractor vehicle and the axis of the two land wheels, the towing frame being attached in use to the tractor vehicle.

2. A spreader as arranged in any preceding Claim in which the track of the land wheels of the chassis is adjustable.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (2)

**WARNING** start of CLMS field may overlap end of DESC **. suit a particular tramline spacing corresponding to the track of the towing tractor. Thus it can be seen that a fertiliser spreader is provided in which the spreading unit can be easily adjusted in height, while maintaining the centre of mass of the spreader at a constant low height, offering particular suitability for treatment of growing crops. Some variations in the design, not shown in the drawings, are possible to meet particular requirements in a spreader, particularly when it is desired to handle very high rates of material distribution or to control the rate and distribution pattern with particular accuracy over a range of height adjustment. Instead of a single spinning disc being provided, for high rates of distribution, two spinning discs may be provided each mounted on the device in a similar manner to the single disc discussed above, and fed by the bifurcated version of the extendable chute. Instead of a single chute being provided the outlet at the top of the elevator may be divided or bifurcated into a plurality of outlets and a respective chute similar to that described above provided for each of that plurality of outlets to feed material either to respective points on a singde disc; or to a respective disc, each of which is again mounted on the device in a similar manner to the single disc discussed above. It is anticipated that two such discs with respective chutes will meet most requirements, but more than two may be used to meet particular needs. In a further arrangement, instead of the outlet of the metering conveyor being divided, two separate conveyers may be provided, each with a respective chute, feeding a respective spinning disc device. In cases where particular accuracy in feed rate and pattern is needed, to compensate for the different characteristics which may be caused in feeding some materials by the variation in vertical drop of material from the metering elevator onto the spinning disc, it may be arranged that this drop is maintained constant over the range of height adjustment. This may be achieved by making the outlet point from the metering elevator adjustable along the slant height of the elevator so that as the spinnning disc is raised, the outlet is also raised to maintain the drop constant. In such an arrangement the mounting of the spinning disc device may be such that during height adjustment, the fore and aft displacement to match that of the elevator outlet is achieved. One manner in which this can be done is to incline the support 38 to match the inclination of the elevator. An alternative manner in which the drop from the elevator outlet to the spinning disc may be maintained constant, is to mount the elevator pivotally at or adjacent its lower end in the hopper; so that, as the spinning disc is adjusted in height, the elevator may be pivoted to maintain the drop constant. Again fore and aft compensation for the spinning disc may be provided. While the above discussion has been in respect of a fertiliser spreader for agricultural use, it will be appreciated that the spreader of the invention can also be used for spreading other powdered or granular materials and in other than agricultural applications, for instance in spreading salt and sand mixture on public highways. Attention is drawn to our co-pending application No. 27492/77 (Serial No. 1604851) from which this application was divided. WHAT WE CLATM IS:-

1. An agricultural spreader arranged to be trailed behind a tractor vehicle, having a wheeled chassis comprising or supporting a container for material to be spread and arranged to be trailed over the ground, in which the chassis is provided with two spaced land wheels and pivotally connected to a towing frame about a vertical pivotal axis arranged to be approximately mid-way between the rear axle of the tractor vehicle and the axis of the two land wheels, the towing frame being attached in use to the tractor vehicle.

2. A spreader as arranged in any preceding Claim in which the track of the land wheels of the chassis is adjustable.