GB2026447A - Hopper feeding and distributing apparatus - Google Patents

Abstract

Mobile implement such as a seed drill for delivering particulate material such as Italian Rye Grass to the ground has a hopper 26 in which at least one agitator 70 is provided to avoid bridging over the hopper outlets and ensure a constant rate of feed from the hopper to one or more flow control mechanisms 72, the or each agitator having spaced elliptical plates 94 mounted at 45 degrees to the axis of an agitator shaft 90. Rotation of the shaft 90 in one direction causes the plates 94 to push material in the hopper axially of the shaft alternately in opposite directions. <IMAGE>

Description

SPECIFICATION Mobile implements for delivering particulate material to the ground This invention relates to mobile implements for delivering particulate material to the ground and in particular, though not exclusively, to such an implement in the form of a mobile agricultural implement for delivering particulate material to the soil or to crops. An example of such an agricultural implement is a seed or combined seed and fertilizer drill for sowing seed or seed and fertilizer respectively in rows.

A problem that arises in such drills is that of providing a uniform flow of seed or fertilizer to each delivery tube of the drill throughout a sowing operation, so that the tube deposits a uniform row of seed or fertilizer in the soil. This problem can be divided into several parts including firstly the problem of ensuring that the seed or fertilizer flows freely from the hopper through a series of outlet openings formed in the hopper and does not "bridge" and form cavities over the outlet openings, and secondly the problem of controlling the free flows through the outlet openings, so that that rate of flow through each opening is neither too high nor too low.

The present invention is concerned primarily with the first of these problems, and it should be noted that this problem in a mobile implement and especially in a mobile agricultural implement is not exactly analogous to flow problems in other machines where a hopper is used to dispense quantities of particulate material. This is because the working environment of an agricultural implement is somewhat unique, and unique in a way which has consequences in relation to the ease with which material will flow out of a hopper of the agricultural implement. For example the material within the hopper of a seed or seed and fertilizer drill may well be subjected to dampness, and it will certainly be subjected to considerable shaking and vibration as the implement traverses cultivated land during use.

Shaking and vibration cause compaction of the material in the hopper, dampness causes resistance to flow.

In addition, certain grass seeds which have a whisker or hair on each seed, such as Italian Rye Grass, have particularly poorflow characteristics and a particularly strong tendency to "bridge" and form cavities over hopper outlet openings. As far as the Applicants know, no effective solution has yet been provided for this old problem, despite many proposals over the years for the use of agitators within the hopper, such as reciprocated shafts driven by cranks, cam-actuated spring steel agitators, au ger-fed extending and retracting feed fingers, pen dulum type vibrated spring agitators etc. etc.

An object of the invention is to provide a mobile implement for delivering particulate material to the ground having improved characteristics as far as concerns the avoidance of "bridging" and the forma tion of cavities within its hopper and the provision of free material flow through an outlet in the hopper.

According to the invention there is provided a mobile implement for delivering particulate material to the ground, the implement comprising: a hopper for particulate material; an outlet formed in the hopper through which material contained in the hopper can flow; and agitating means mounted within the hopper in the region of the outlet, to promote the free flow of material through the outlet; the agitating means comprising a shaft mounted in the hopper for rotation about a rotation axis extending lengthwise of the shaft, a drive to rotate the shaft, and an agitator member mounted on the shaft for rotation with the shaft;; wherein the agitator member has structure defining a periphery of the agitator member, the periphery extending around the shaft and the periphery being mounted at an attitude with respect to the rotation axis of the shaft such that the periphery pushes particulate material in the hopper axially of the shaft alternately in opposite directions as the agitator member rotates in one direction.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 shows a section through a combined seed and fertilizer drill having agitating means in its hopper, the section being taken in the direction of operative forward motion of the drill; Figure 2 shows a perspective view of the drill of Figure 1; Figure 3 shows a portion of Figure 1 on a larger scale; Figure 4 shows a perspective view of a portion of the drill of Figure 1 including the agitating means, the direction of viewing being indicated approximately by arrow IV in Figure 1; Figure 5 shows somewhat diagrammatically, a portion of the agitating means of the preceding Figures as seen in side elevation; and Figure 6 shows the agitating means as viewed in the direction of arrow VI in Figure 3; and Figure 7shows, in a view similarto that of Figure 3, the use of the agitating means of the preceding Figures in a drill having a fluted roller type seed dispensing mechanism.

As shown in Figures 1 and 2 a mobile agricultural implement for delivering particulate material to the soil in the form of a combined seed and fertilizer drill 10 comprises a frame 12 mounted on a pair of ground-engageable end wheels 14 and having a drawbar 16, whereby the drill is drawn by a tractor during use. Drill 10 is a "Direct Drill" intended principally for use in sowing seed into land which has not been subjected to the usual tillage operations such as ploughing and harrowing after harvest ing the previous crop, or which has only undergone minimum tillage. The land is usually sprayed with a weed killer such as "Gramoxone" (Trade Mark) before sowing. Such a drill is also known as a "no-till" drill.

Frame 12 comprises transverse front and rear beams 18 and 20 respectively, fore/aft extending end beams 22, and a pair of transversely - spaced bridge shaped fore/aft frame members 24, 25.

A hopper 26 having an upright partition 27 divid ing it into a front seed compartment 28 and a rear fertilizer compartment 30 is mounted on frame 12 by a pair of sheet steel end plates 31,32 one at each end of the hopper. The hopper has two hinged lids 33 divided by a central loading platform 34.

Two rows of triple disc coulters 35, each comprising a forward slit opening disc 36, and a pair of rear slit-widening discs 38, are mounted on front beam 18 of frame 12 by respective long and short mounting arms 40 and 42 respectively, which are connected to beam 18, by pivots 43.

Coulters 35 are raised and lowered relative to frame 12 by a pair of upright hydraulic rams 44,45 carried by frame members 24. Each ram has a piston 46 pivotaliy connected to a laterally - extending box section coulter-actuating beam 48 which is itself mounted for up and down movement relative to frame 12 on spaced pairs of parallelogram linkages 49, which pivotally connect the box beam to frame 12 through upstanding brackets 50,51 on the beam and the frame respectively.

Coulter actuating beam 48, is connected to coulter mounting arms, 4042 by a series of ellipsoidal rubber springs 52, which transmit downwards thrust during sowing and have internal wire cables (not shown) to lift the coulters to their transport position.

Springs 52 are more fully described in the specification of British Patent No. 1,536,426.

Drill 10 has a series of sets of dispensing mechanisms 56 and 58 for dispensing seed and fertilizer respectively into a series of rubber funnels 60, 62 and respective rubber convoluted tubes 64, 65 connected to seed and fertilizer drop tubes 66, 67 between the discs of each pair of discs 38, so that seed and fertilizer are placed in the furrows in the soil produced bythe coulters 35. Two such dispensing mechanisms are provided for each crop row.

The sets of dispensing mechanisms 56 and 58 are substantially identical in structure and each comprises hopper 26 (common to all the sets of dispensing apparatus) for the particulate material to be dispensed, an outlet 68 formed at the bottorn of the hopper through which seed and fertilizer contained in the hopper can flow, agitating means 70 mounted within the hopper in the region of outlets 68 to promote the free flow of material through the outlets, and a flow control mechanism 72 (associated with funnel 60 or 62 and convoluted tubes 64 and 65) to control the flow of seed or fertilizer through outlets 68.

Hopper 26 has downwardly - converging front and rear sheet metal walls 74 and 76 respectively. At the lower edge of partition 27 is provided a generally roof-shaped sheet metal guide member 78 extending lengthwise of the hopper and having downwardly sloping walls 80 and vertical walls 82 (see Figure 3).

As shown in Figures 3 and 4 front wall 74 of hopper 26 and vertical wall 82 of guide member 78 together define a trough or well extending lengthwise of the hopper. A similar well 85 is provided in fertilizer compartment 30 of the hopper. The wells 84 and 85 have flat base walls 86 in each of which a series of rectangular apertures 88 are formed, one aperture 88 for each hopper outlet 68 and for each dispensing mechanism 56 or 58.

Each agitating means 70 comprises a shaft 90 mounted in the well 84 or 85 of its compartment of hopper 26, for rotation about a respective rotation axis 91 or 92 extending lengthwise of the hopper.

Each shaft 90 extends lengthwise of the hopper at right angles to the direction F of operative forward motion of drill 10, so as to be positioned above the series of outlets 68 formed in the hopper.

A drive (not shown) is provided to rotate shafts 90 in directions R. The drive comprises a chain drive, and a train of gears in the form of gear boxes 93 as described in British Patent Specification 1,496,682, connected to one of the ground wheels 14 of the drill. The drive may however be of any well-known form and it is therefore not considered necessary to illustrate it.

Agitator shafts 90 are constructed so as to be quickly and easily mountable in and dismountable from hopper 26 with correspondingly simple means for connecting them to and disconnecting them from their drives. In this way drill 10 can be quickly and easily adapted to sow Italian Rye Grass and similar seeds.

Since shafts 90 rotate very slowly they do not need special bearings and it is sufficient to provide a shaft support at each end of each shaft 90, such support being for example in the form of a fixed collar or wire loop in which the shaft is an easy or loose fit. Each shaft is coupled to its drive at one end of the shaft for example by means of a clevis and an associated pivot pin (not shown) or any other suitable means.

A series of agitator members 94 is mounted on each shaft 90 for rotation with the shaft, members 94 being at spaced-apart positions throughout the length of the hopper 26 in which the outlets 68 are formed.

Each agitator member 94 is in the form of a flat plate of steel sheet having an elliptical periphery 95 and welded to shaft 90 for rotation with the shaft.

The agitator members are mounted on shafts 90 so as to be inclined at 45 degrees with respect to the rotation axis 91,92 of the shafts so that the agitator members, and in particular their peripheral regions, push particulate material in hopper 26 axially of shafts 90 alternately in opposite directions as the agitator members rotate in direction R.

The form of the ellipse of each agitator member 94 taken together with the attitude of the agitator member with respect to its rotation axis 91 or 92 (in this embodiment 45 degrees, but the invention is not limited to this angle) are such that the profile of the agitator member when viewed in the direction of its axis 91 or 92 (arrow VI in Figure 5) is circular, as shown in Figure 6.

As regards the specing and relative dispositions of the agitator members 94, as shown in Figures 4 and 5 they are all in phase with each other as regards their attitudes with respect to angular movement around the rotation axis 91 or 92 of their respective shafts 90. The axial spacing of members 94 along shafts 90 is preferably such that the volumes of rotation described by the agitator members as they rotate, just touch or just overlap each other. The agitator members are all of the same size and shape.

In Figure 5, for purposes of illustration small gaps 96 have been shown between the volumes of rotation of the agitator members. Figure 5 shows at 94 and at 94 (R) the agitator members in the limiting positions and attitudes they occupy during rotation of shaft 90 at successive 180 degrees of such rotation.

Flow control mechanisms 72 are more fully described in our British Patent Applications Nos.

7919030,7919031 and 7919032 and each such mechanism comprises a dispensing roller 98 and an associated glass, dispensing plate 100. Dispensing plates 100 are mounted over respective rectangular windows 102 stamped out of vertical flanges 104, 106, depending from front and rear walls 74, 76 respectively, of hopper 26.

Rollers 98 are mounted on shafts 108, journal- led on frame 12 of the drill for rotation about respective axes 112, 114 by a drive connected to ground wheels 14. The same drive is connected to agitator shafts 90 and includes ratio changing gearboxes 93.

As shown in Figure 4, the feed rollers 98 themselves are formed of non-foamed polyurethane moulded with internal axially - extending cylindrical recesses 116,188,120. Afull description of the rollers is included in the specification of application 7919030.

During use of drill 10, the drill is trailed from the drawbar of a tractor. Coulters 35 are pressed into the ground by rams 44 and 45 and open furrows in the ground, ground wheels 14 drive agitating means 70 and flow control mechanisms 72 whereby each coulter receives seed and fertilizer through tubes 64 and 65 respectively at the desired rate, and the seed and fertilizer is placed in the furrows.

The mode of operation of agitating means 70 is best understood by reference to Figure 5, in which the agitator members are shown in their limiting positions at 94 and 94 (R). As shafts 90 rotates, the agitator members smoothly and progressively move between these positions. The rate of rotation of shafts 90 is linked to the rate of rotation .of shafts 108, 110 carrying dispensing rollers 98, by the drive train, and the rate of rotation of all the shafts is variable by means of gearboxes 93. For general purposes, the rate of rotation of shafts 90 is between 5 and 10 (preferably about 8) revolutions per minute.

As can be seen from consideration of the limiting positions 94 and 94 (R) of the agitator members 94, they push seed or fertilizer in the axial direction of shafts 90 alternately in opposite directions as indicated in Figure 5 by double headed arrows P.

Furthermore, it will be understood that each agitator member 94 pushes seed or fertilizer towards the region from which the next successive agitator member on shaft 90 is itself removing seed or fertilizer. So, it can be seen that the whole assembly of agitator members effects oscillating axial movement of the mass of seed in the region of hopper outlets 68. This inhibits the formation of cavities within the seed or fertilizer as occurs with previously known agitators. It is on account of the concerted action of the assembly of agitator members 94, one moving material into the "space" created by the next agitator member, that the torque requirement of agitating means 70 is relatively low as compared with fingers mounted on a shaft to effect a stirring action, for example.

From this it can be seen that the axial spacing of the agitator members is significant in relation to their function. Preferably their volumes of rotation should touch or overlap slightly. If there is a gap 96 between the volumes of rotation, then the width of gap which is acceptable depends on the material to be handled within the hopper and on the thickness of the material from which the agitator members 94 are made. The width of the gap can be increased as the flow resistance of the material handled decreases and the gap can be increased if thin plates are used for the agitator members themselves, on account of the effective disturbance of material thus provided around the periphery of the agitator members.

It is to be understood that the rotating agitator members 94 do not, of course, provide pure axial movement for the material within the hopper. The movement is a maximum at the periphery of each side plate and diminishes towards axis 91, or 92 (thus giving a shearing action within the material being agitated), but in addition the mass of seed or fertilizer in the region of shafts 90 has some rotational movement superimposed on its axial movement and thus the material executes 3 dimensional movement.

Figure 7 shows the use of agitating means 70, constructed as described above, in a drill otherwise as described above but having seed dispensing mechanisms 122 of the fluted roller kind, as described in British patent no. 964,279 for example.

Mechanisms 122 are actually more fully described in application No. 7919032. For present purposes it suffices to say that each mechanism 122 has a dispensing roller 124 comprising a cylindrical portion 126 and a fluted portion 128 mounted on a rotatable shaft 130. Shaft 130 and rollers 124 are shiftable axially through housings 132 to change the rate at which seed entering the housings through outlets 134 from the hopper 136 is dispensed over the outer edges of adjustable tongues 138 into funnels 140 and seed delivery tubes 142. Fiuted roller portion 128 may be replaced by a roller portion having much smaller flutes.

Agitating means 70 operates in the manner described above in connection with the preceding embodiment to push seed alternately in opposite directions along the bottom of hopper 136 thereby inhibiting the formation of bridges and cavities around the hopper outlets 134 and promoting free flow of seed to dispensing mechanisms 122.

Among modifications which could be made in the above embodiments which nevertheless are within the scope of the invention, are the following: 1. Modifications to the shape of agitator members 94, including the use of non-elliptical (for example circular) agitator members; 2. Modifications to the structure of the agitator members, for example the use of structure (such as steel sheet) defining periphery of a suitable shape for each agitator member, the periphery extending around shaft 90 and being mounted at an attitude with respect to axis 91 or 92 of the shaft such that the periphery pushes particulate material in the hopper axially of the shaft alternately in opposite directions as the shaft rotates. Any suitable method of mounting the periphery on the shaft can be adopted such as spokes, a plate or otherwise; 3. Modifications to the attitude of the agitator member or members (or more particularly its periphery) with respect to the rotation axis 92 of shaft 90 can be made. The angle should not be less than 30 degrees and an angle of 50 degrees is expected to be satisfactory - subject of course to the necessary axial spacing of the agitator members from each other; 4. Use of the agitating means in a small seeds box of the kind attached to a standard seed drill for broadcasting grass seed, for example, at the same time as a cereal crop is drilled. Also use of the agitating means in other agricultural implements (for example crop treatment implements and precision fertilizer placement implements) and in nonagricultural applications involving dispensing particulate material from a hopper; 5. Rotation of the agitator shafts in the opposite direction to the directions R shown in the drawings.

Claims (11)

1. A mobile implement for delivering particulate material to the ground, the implement comprising: a hopper for particulate material; an outlet formed in the hopper th rough which material contained in the hopper can flow; and agitating means mounted within the hopper in the region of the outlet, to promote the free flow of material through the outlet; the agitating means comprising a shaft mounted in the hopper, for rotation about a rotation axis extending lengthwise of the shaft, a drive to rotate the shaft, and an agitator member mounted on the shaft for rotation with the shaft;; wherein the agitator member has structure defining a periphery of the agitator member, the periphery extending around the shaft and the periphery being mounted at an attitude with respect to the rotation axis of the shaft such that the periphery pushes particulate material in the hopper axially of the shaft alternately in opposite directions as the agitator member rotates in one direction.

2. An implement according to claim 1 having at least one further agitator member mounted on the shaft for rotation with the shaft, the further agitator member being spaced axially along the shaft from the first agitator member and being of similar form to the first agitator member, the two agitator members being mounted on the shaft so as to be in phase with each other as regards their attitudes with respect to angular movement around the rotation axis, whereby each agitator member pushes particulate material in the hopper axially of the shaft towards the region from which the other agitator member is removing material.

3. An implement according to claim 2 wherein the volumes of rotation described by the agitator members as they rotate overlap each other.

4. An implement according to any preceding claim wherein the or each agitator member comprises a flat plate.

5. An implement according to claim 4 wherein the flat plate is formed of sheet material.

6. An implement according to any preceding claim wherein the periphery of the or each agitator member is elliptical in form.

7. An implement according to claim 6 wherein the attitude of the or each agitator member with respect to the rotation axis of the shaft, and the form of the ellipse of each agitator member taken together, are such that the profile of the agitator member when viewed in the direction of the rotation axis is circular.

8. An implement according to any preceding claim in the form of a mobile agricultural implement for delivering particulate material to the soil or to crops, the agricultural implement comprising a frame, the hopper being mounted on the frame, so as to extend lengthwise at right angles to the direction of operative forward motion of the agricultural implement, and the hopper having a series of outlets formed in it through which seed, fertilizer or other agricultural particulate material contained in the hopper can flow, the agricultural implement further comprising a series of flow control mechanisms and associated conduits connected to the outlets to control the flows of particulate material through the outlets, the shaft being mounted in the hopper so as to be positioned above the series of outlets formed in the hopper, a series of said agitator members being mounted on the shaft at spacedapart positions throughout the length of the hopper in which the outlets are formed.

9. An agricultural implement according to claim 8 in the form of a seed drill having removable means for adapting the drill to sow Italian Rye Grass or similar seed, the removable means comprising said shaft and said agitator members, said shaft being quickly mountable in and dismountable from the hopper of the drill and being adapted to be quickly connected to and disconnected from a drive in the hopper.

10. An implement according to claim 1 wherein the agitating means is substantially as described herein and as illustrated in the accompanying drawings.

11. Agitating means comprising a shaft adapted to be mounted in a hopper, for rotation about a rotation axis extending lengthwise of the shaft, and an agitator member mounted on the shaft for rotation with the shaft; wherein the agitator member has structure defining a periphery of the agitator member, the periphery extending around the shaft and the periphery being mounted at an attitude with respect to the rotation axis of the shaft such that the periphery pushes particulate material in the hopper axially of the shaft alternately in opposite directions as the agitator member rotates in one direction.