GB2033717A - Tank for root crop harvesters - Google Patents

Abstract

A tanker-type root crop harvester has an endless discharge conveyor 38 to discharge crop from the tank and a pivotable floor 200, 202 in the tank, actuable by a double acting ram 186, to ensure complete tank emptying. Pivotal movement of the discharge conveyor to a retracted transport position is achieved by means of a link 228 which can be connected between the floor and the discharge conveyor to enable the floor-actuating ram to retract the discharge conveyor. <IMAGE>

Description

SPECIFICATION Root crop harvesters This invention relates to root crop harvesters such as sugar beet harvesters and potato harvesters and in particular to such harvesters having a hopper to receive harvested root crop.

Many and varied arrangements have been proposed for loading and unloading the hoppers of root crop harvesters, and it is an object of the present invention to provide a root crop harvester having a hopper to receive harvested root crop together with conveyors for charging and discharging the hopper, and the harvester providing a better compromise than previously proposed arrangements between manufacturing cost on the one hand, and operational efficiency so far as concerns hopper capacity and facilities for discharging crop from the hopper, on the other hand.

According to the invention there is provided a root crop harvester comprising: a frame; ground wheels to support the frame; a hopper mounted on the frame to receive harvested root crop; root crop lifting means; conveyor means to convey lifted roots into the hopper; and a discharge conveyor provided in the hopper to discharge roots from the hopper;; wherein the hopper comprises a movable wall pivotally mounted on the frame for movement between a discharge position in which it slopes towards the discharge conveyor and a retracted storage position providing greater storage capacity for roots in the hopper than in the discharge position of the movable wall, the discharge conveyor being pivotally mounted on the frame for movement between an extended discharge position and a retracted transport position, and a hydraulic ram connected to the frame being selectively connectible to the movable wall and to the discharge conveyor to effect pivotal movement of said wall and conveyor between their discharge and retracted positions.

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 side and front perspective view of a sugar beet harvester and tractor in operation harvesting beet; Figure 2 shows a plan view of the harvester of Fig. 1; Figures 3 and 4 show side elevation and rear elevation views respectively of the harvester of the preceding Figures, the directions of viewing being indicated by arrows Ill and IV in Fig. 2. In Fig. 4 a guard over a rotary transfer device is shown partly cut away to show the transfer device itself and its relationship to other parts of the harvester; Figure 5 shows a side and rear perspective view of the tractor and harvester seen in Fig.

1, the direction of viewing being indicated by arrow V in Fig. 2; Figure 6 shows a perspective view of the rotary transfer device seen in Figs. 4 and 5, the direction of viewing being indicated by arrow VI in Fig. 2; Figure 7shows an exploded perspective view of the parts which make up the rotary transfer device of the preceding Figures; Figure 8 shows, diagrammatically, a section on the line VIII-VIII in Fig. 2 through transfer restriction means between primary and secondary conveyors of the harvester; Figure 9 shows a front elevation view of the harvester; and Figure 10 shows an exploded perspective view of a hopper or tank of the harvester, with a two-part movable wall of the tank shown outside the tank for illustration purposes.

As shown in the drawings, a root crop harvester in the form of a sugar beet harvester 10 comprises a frame 1 2 mounted on rear ground wheels 14, 1 6 a drawbar 1 8 whereby the harvester is drawn by a tractor 20, and a drive input shaft 22 for connection to the power-take-off drive of the tractor.

Harvester 10 further comprises a pre-topper (not shown) for removing the tall growth from beet which has gone to seed (seedy beet), root topping means in the form of a main beet topper 24 to remove the leafy matter from beet to be harvested, and an associated top cleaning and soil clearing disc 25, and a root crop lifting assembly comprising a pair of beet lifting wheels 26, 27 to lift from the ground roots to be harvested, the wheels being preceded by associated skids 28, 29. In addition there is a primary elevator conveyor 30 or digger web, a rotatable transfer device or scrubber 32, a secondary elevator conveyor 34, a hopper or tank 36 for harvested beet mounted on frame 12, and a discharge elevator conveyor 38 provided in hopper 36 to discharge beet from the hopper.

The above mentioned principal parts of harvester 10 will now be described in more detail.

Drive input shaft 22 drives all mechanisms of harvester 10, except the main topper 24, through a drive train comprising input shafts 40 and associated universal joints 42, a principal bevel gearbox and an associated countershaft together with certain belt drives and chain and sprocket drives and shaft and gearbox drives. These latter parts of the drive train are identified collectively in the drawings by reference numeral 44.

Main topper 24 is driven from ground wheel 1 6 through gearboxes 46, 48 a shaft 50 and a chain and sprocket drive 52.

The principal components of main beet topper 24 are a topper support frame 54, a blade support arm 56 carrying a horizontal topper blade, and a feeler wheel 58 positioned above the blade and connected to chain and sprocket drive 52 for rotation at a rate slightly greater than that at which it would rotate if allowed to run freely along the ground.

Topper support frame 54 is mounted on main frame 1 2 for pivotal movement about horizontal axis 60 at its front end and is counterbalanced at its rear end by a double acting coil compression spring assembly 62.

Blade support arm 56 is mounted on topper support frame 54 for pivotal movement about a horizontal axis 64 at its rear end and is supported at its front end by a tension spring 66 to allow the blade limited downward movement away from feeler wheel 58 to allow clearance of rocks and stones. Top cleaning disc 25 is journalled on an arm 67 carried by frame 12.

A top clearing device 68 comprising pivoted rubber flails 70 rapidly rotated by the tractor's p.t.o. about a horizontal fore/aft axis 72 is positioned behind topper 24 to clear severed tops laterally away from the topped but as yet unlifted roots.

Beet lifting wheels 26, 27 are mounted in spaced-apart face-to-face relationship, for free rotation about respective axes which are inclined so that the wheels converge both downwardly and rearwardly.

A set of pivoted rubber flails is mounted for rapid rotation about a horizontal axis in a path which takes them between the lifter wheels thereby promoting the smooth flow of crop onto primary elevator conveyor 30. The flails are enclosed by a housing 74.

The primary elevator conveyor 30 comprises a pair of spaced endless flexible tension members 76, 78 one at each edge of the conveyor and joined by a series of spaced parallel bars 80 providing a grid or web on which the lifted crop is conveyed while earth is shaken out and passes between the bars and falls to the ground. The Conveyor is trained round front rollers 82 rear driven sprockets 84 and guide rollers 86, 88, 90 in an upper conveying run 92 and a return run 94 and is driven in the directions indicated, by the tractor's p.t.o. An undriven and optionally weighted length of conveyor 95 similar to conveyor 30 and called a top trace, is mounted adjustably over run 92 so as to hang down into the path of the crop and thereby slow down the crop and promote thorough crop cleaning.

The inlet end 96 of primary conveyor 30 is positioned immediately behind lifting wheels 26, 27 and the conveyor extends upwards and rearwards with respect to the direction F of operative forward motion of harvester 10 at a relatively shallow inclination of 1 6 degrees with respect to the horizontal. This angle may be up to 25 degrees but is preferably not more than 20 degrees.

The discharge end 98 of primary conveyor 30 is positioned considerably rearwards of hopper 36 at a position at the rear end of the harvester 10 from which clods, earth, stones, crop tops and other unwanted matter 100 can be conveniently discharged onto the ground.

The difference in height between the inlet and discharge ends 96 and 98 of conveyor 30 when harvester 10 is standing on horizontal ground is not more than 800 millimetres.

The position of primary conveyor 30 with respect to hopper 36 is such that the conveyor passes below the non discharge side 102 of the hopper (on the unharvested crop side of the machine).

Secondary elevator conveyor 34 is very much more steeply inclined with respect to the horizontal than primary conveyor 30, as shown in Fig. 3, and has a lower end or inlet end 104 laterally offset (on the harvested crop-side of the machine) from the discharge end 98 of conveyor 30, to receive roots from conveyor 30. Conveyor 34 extends in direction F, parallel to conveyor 30 upwards and forwards from its inlet end and has a discharge end 106 positioned to discharge roots into hopper 36. The structure of conveyor 34 is substantially the same as that of conveyor 30 except that conveyor 34 is provided on every eighth bar 80 with a row of upstanding root carrying fingers 108 each 10 centimetres in length and having a slightly bent profile to retain roots more securely.

Rotatable crop transfer device 32 is positioned above the discharge end 98 of primary conveyor 30 and is rotatable by the tractor's p.t.o., about a horizontal axis 110 transverse to direction F and in the direction indicated, to transfer roots from the discharge end 98 of conveyor 30 to the inlet end 104 of secondary conveyor 34. The transfer device comprises a drum 11 2 carrying a projecting transfer formation arranged in the form of a helix on the external surface of the drum. The transfer formation comprises five helically disposed and equally circumferentially spaced rows 114 of rubber strips 116, each strip being secured by a bolt 11 8 and associated nut 1 20 to its own mounting flange 122 welded to drum 112, there being ten strips and flanges in each row.

Drum 11 2 is of diameter 450 millimetres and extends across the full width of primary elevator 30. Rubber strips 11 6 are of hardness 90 degrees on the shore A scale, thickness (T) 20 millimetres, width (W) 40 millimetres, length (L) 100 millimetres and exposed length (above flanges 122) 65 milli metres. The angle of the helix of each row 114 of rubber strips is such that opposite ends of successive rows 114 are axially aligned.

As shown in Fig. 7, drum 112 is mounted on a shaft 1 24 journalled in bearings 1 26 bolted to a pair of upright posts 128 which are themselves slidingly received in a pair of supports 1 30 welded to harvester frame 1 2.

The posts 1 28 also carry a pair of brackets 1 32 for a sheet metal guard 1 34 for transfer device 32.

A sprocket 1 36 is keyed to shaft 1 24 and forms part of drive train 44, whereby drum 11 2 is rotated in the direction indicated i.e.

opposing the travel of roots below the drum, at a rate of 45 revolutions per minute (at a ground speed of 6.4 kilometres per hour).

Height adjustment for transfer device 32 relative to the rear end 98 of primary conveyor 30 is provided by means of two cams 1 38 received on a hexagon shaft 140 which is itself rotatably received in apertures 1 42 in a pair of flanges 144 welded to frame 1 2.

The lower ends of posts 1 28 rest on cams 1 38. Rotation of shaft 140 by means of a spanner causes the cams to adjust the clearance between transfer device 32 and primary conveyor 30 from a nominal minimum up to 50 millimetres. A locking screw 1 46 is provided to lock the assembly at any desired working height. Adjustment of the height of transfer device 32 enables it to be adapted to any particular set of harvesting conditions so as to retain all the root crop while allowing a maximum amount of unwanted material to pass below the device and be discharged onto the ground. Many other simple height adjustment mechanisms could equally well be used.

A small transfer hopper 148 is provided to collect beet transferred by device 32 and to retain each beet until it is picked up by the next row of fingers 108 on secondary conveyor 34. Hopper 148 comprises side walls 150, 1 52 and a grid of bars 1 54 forming the rear of the hopper. The front of the hopper is constituted by the lower end of secondary conveyor 34 itself.The lower portion 1 56 of each bar 1 54 is mounted on a transverse pin (not shown) for upward pivotal movement about a transverse axis 1 58 from its rest position shown in the drawings in order to allow the passage of fingers 108 through hopper 34 even when stones are jammed between the fingers 1 08. The portions 1 56 of bars 1 54 return to their rest position under their own weight.

As shown in Figs. 2 and 8, transfer restriction means is provided in the region of the discharge end 98 of primary conveyor 30 to restrict the transfer of roots to secondary conveyor 34 by transfer device 32, whereby the roots are subjected to extra cleaning on the primary conveyor before transfer. The transfer restriction means comprises a fixed gate 1 60 positioned between and extending lengthwise parallel to the primary and secondary conveyors 30 and 34 respectively above the right hand side wall 1 52 of transfer hopper 148. Gate 1 60 is in the form of a channel section sheet metal pressing which thus gives the top edge 1 62 of the gate a rounded profile.One side 1 64 of the gate is integral with side wall 1 52 of hopper 148, and the other side 1 66 of the gate has a flange 1 68 clamped between a nylon runnerstrip 1 70 (on which primary conveyor 30 runs) and frame 1 2 of the harvester. The height (H) of gate 1 60 is 95 millimetres and its length (i.e. the length of the transfer opening between conveyors 30 and 34) 465 millimetres.

The transfer restriction means could be made adjustable to vary the degree of restriction offered-and therefore to vary the degree of extra cleaning provided. The transfer restriction means could, for example, comprise an adjustable gate located in the path of roots between the primary and secondary conveyors 30 and 34, or could be simply in the form of a flow restriction positioned in the region of the discharge end 98 of primary conveyor 30 and in front of transfer device 32 so as to restrict the flow of roots on the primary conveyor to the transfer device.

Discharge conveyor 38 is of similar construction to secondary conveyor 34 having endless tension members 1 72 and root carrying fingers 1 74 which pass through main hopper 36 to pick up roots and discharge them from the hopper. The discharge conveyor and two associated side plates 1 76 form one side wall 1 78 of hopper 36 and is pivotally mounted on frame 1 2 for movement about an axis 1 80 in the region of its lower end between an extended discharge or working position shown in the drawings and a retracted transport position in which the overall width of the harvester 10 is significantly reduced.

A row of beet retaining fingers 1 82 is mounted at the left hand side (i.e. the harvested crop side) of hopper 36. The fingers mesh with root carrying fingers 1 74 as shown in Fig. 2, and fingers 182 are mounted for upward pivotal movement on a common pin (not shown) parallel to axis 1 80 to permit overload release when, for example, stones are jammed between fingers 174 as in the case of bars 1 54.

The other side wall 1 84 of hopper 36 is in the form of an articulated movable wall pivotally mounted on the frame 1 2 for movement by means of a double-acting ram 1 86 between a discharge position in which it slopes towards discharge conveyor 38, and a retracted storage position providing greater storage capacity for roots in the hopper during harvesting and transport.

The structure of movable wall 1 84 is shown in Fig. 10 and comprises a floor panel 200 and a side panel 202 which are mounted so as to be freely movable between limit positions within the open framework defined by harvester frame 12, front and rear hopper walls 204 and 206 respectively and connecting bars 208 (only one shown in Fig. 10).

Floor panel 200 is pivotally connected at the harvested side of the machine by a pivot rod 210 to frame 12. Rod 210 defines the pivot axis 1 80 and on it are also pivoted beet retaining fingers 1 82 and discharge conveyor 38 itself. Brackets 212 are provided on frame 12 to receive rod 210.

Side panel 202 is hinged to floor panel 200 by means of a pivot rod 214 which locates the panel at its lower end. The upper end of panel 202 is located by the fixed connecting bar 208 shown in Fig. 10 and by a pair of rollers 216 rotatably mounted on respective brackets 218, 220 at the cropside upper ends of hopper walls 204 and 206 respectively. Sufficient clearance is provided between rollers 216 and bar 208 for panel 202 to execute the angular movement described below.

Hydraulic ram 186 is pivotally connected at its lower end to a pair of brackets 222 welded to frame 12, and at its upper end the ram is pivotally connected to a pair of brackets 224 welded to an angle section 226 which is itself welded to the underside of floor panel 200.

A link 228 in the form of a length of hollow section bar having a aperture at each end is provided to interconnect movable wall 1 84 and discharge conveyor 38 so that when the link is connected, hydraulic ram 1 86 can move both the wall and the conveyor to their retracted positions. For this purpose, link 228 is connected at one end by a nut and bolt to a pair of ears 230 at the underside of floor panel 200. A slot 232 is formed in panel 200 to receive link 228 for this purpose. The other end of link 228 is selectively connected by a quick release coupling 234 to discharge conveyor 38 itself.

Quick release coupling 234 comprises a spring-biased handle 236 having a long coupling rod (not shown) formed integrally therewith. The rod extends between the upper and lower runs of the conveyor 38 through a pair of apertured ears (not shown) on the frame of conveyor 38. Manual retraction of handle 236 against the action of the spring enables the end of link 228 to be passed between the ears and retained by allowing the spring to return the coupling rod through the aperture in the end of link 228.

Fig. 9 shows, diagrammatically the various positions of discharge conveyor 38 and panels 200 and 202.

Firstly, when tank 36 is being unloaded by conveyor 38 and is almost empty, ram 1 86 is extended to move panels 200, 202 from their harvesting positions 200 (P1) and 202 (P1) to their discharge positions 200 (P2) and 202 (P2) in order to ensure complete emptying of the tank. When discharge is complete, double acting ram 1 86 is retracted to return panels 200 and 202 to their P1 positions ready for further harvesting.

Secondly, when a farmer wishes to reduce the width of his harvester for road transport for example, he extends ram 1 86 to bring panels 200, 202 to their extended P2 positions and connects link 228 between ears 230 and quick release coupling 234 as already described.

He then releases fasteners at certain locations e.g. 238, to allow discharge conveyor to pivot relative to tank 36, stows the drive shaft 44 for conveyor 38 on a bracket 240 (Fig. 4) and retracts ram 1 86 to bring the conveyor to its transport position.

If it is desired to reduce the overall height of the harvester with respect to the 38 (P2) position, e.g. for rail transport, conveyor 38 can be further retracted to the 38 (P3) position shown in Fig. 9. This is achieved by first securing by fasteners at 242 the conveyor, then removing link 228, extending ram 1 86 and attaching a shorter link 244 in place of link 228, removing the fasteners and retracting the ram.

In use, topped beet are lifted by wheels 26, 27 onto the inlet end 96 of primary conveyor 30 which conveys the roots rearwards while sieving out soil. At the rear end 98 of conveyor 30, the helically arranged rows 114 of rubber strips 11 6 engage the beet while earth, clods, stones and crop tops pass under the device and are discharged onto the ground.

The beet themselves are impelled by rubber strips 11 6 towards transfer hoppper 148.

Gate 1 60 restricts the flow of beet into hopper 148 so that each root is tumbled for a while on primary conveyor 30 (and is thereby further cleaned) before it drops into hopper 148. It has been observed during field tests that beet are in many cases propelled towards gate 1 60 three times unsuccessfully before they finally pass over the gate.

The spacing of bars 1 54 of hopper 148 allows further loss of soil as each beet drops into the hopper, and the roots are relatively clean when they are picked up by fingers 108 and delivered to hopper 36 ready for periodic discharge by conveyor 38 into a trailer or the like.

The principal advantages of the embodiment of the invention described above lie in the simple and economical arrangements described above for emptying tank 36 and for moving discharge conveyor 38 to its transport position.

The invention is applicable to most forms of tanker type root crop harvester. It will of course be understood that many alternative methods of connecting ram 1 86 to conveyor 38 could be used.

Claims (4)

1. A root crop harvester comprising: a frame; ground wheels to support the frame; a hopper mounted on the frame to receive harvested root crop; root crop lifting means; conveyor means to convey lifted roots into the hopper; and a discharge conveyor provided in the hopper to discharge roots from the hopper;; wherein the hopper comprises a movable wall pivotally mounted on the frame for movement between a discharge position in which it slopes towards the discharge conveyor and a retracted storage position providing greater storage capacity for roots in the hopper than in the discharge position of the movable wall, the discharge conveyor being pivotally mounted on the frame for movement between an extended discharge position and a retracted transport position, and a hydraulic ram connected to the frame being selectively connectible to the movable wall and to the discharge conveyor to effect pivotal movement of said wall and conveyor between their discharge and retracted positions.

2. A root crop harvester according to claim 1 wherein the hydraulic ram is connected to the movable hopper wall, and a selectively connectible link is provided to interconnect the movable wall and the discharge conveyor so that when the link is connected the hydraulic ram moves both the wall and discharge conveyor.

3. A root crop harvester according to claim 1 substantially as described herein and as illustrated in the accompanying drawings.

4. A root crop harvester substantially as described herein and as illustrated in Figs. 3, 4, 9 and 10 of the accompanying drawings.