GB2033201A - Root-crop Topper Mounting - Google Patents

Abstract

A topper for a beet harvester is suspended from the harvester frame by a large diameter double-acting compression spring assembly 62 which fully offsets the weight of the topper mechanism and resiliently resists both upward and downward movement of the topper from the mean position. The compression spring assembly is connected to the harvester frame by a simple position adjustment mechanism 200 which allows adjustment of the mean position (and therefore of the topping height) without tampering with the setting of the springs themselves. <IMAGE>

Description

SPECIFICATION Sugar Beet Harvesters This invention relates to sugar beet harvesters incorporating root topping means to remove leafy matter from beet to be harvested.

An object of the invention is to provide a sugar beet harvester having root topping means mounted on the harvester by an improved mounting mechanism permitting up and down floating movement of the root topping means during use.

According to the invention there is provided a sugar beet harvester comprising: a frame; ground wheels to support the frame; root topping means to remove leafy matter from beet to be harvested; the root topping means being mounted on a mounting arm which is pivotally connected to the frame to permit up and down movement of the root topping means relative to the frame; and a double acting spring assembly acting between the frame and the mounting arm to resiliently resist both upwards and downwards movement of the arm during use.

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 Figure 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 Figure 2.In Figure 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 Figure 1, the direction of viewing being indicated by arrow V in Figure 2; Figure 6 shows a perspective view of the rotary transfer device seen in Figures 4 and 5, the direction of viewing being indicated by arrow VI in Figure 2; Figure 7 shows 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 VIll-VIll in Figure 2 through transfer restriction means between primary and secondary conveyors of the harvester; Figure 9 shows an exploded view of a root topping mechanism of the harvester; and Figures 10 and 11 show perspective views of details of the root topping mechanism (see arrows X and Xl in Figure 2).

As shown in the drawings, a root crop harvester in the form of a sugar beet harvester 10 comprises a frame 12 mounted on rear ground wheels 14, 1 6 a drawbar 18 whereby the harvester is drawn by a tractor 20, and a drive input shaft 22 for connection to the power-takeoff 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 12 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 1 0 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 Figure 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 112 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 11 6, each strip being secured by a bolt 11 8 and associated nut 1 20 to its own mounting flange 122 welded to drum 11 2, there being ten strips and flanges in each row.

Drum 112 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 millimetres. 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 Figure 7, drum 112 is mounted on a shaft 124 journalled in bearings 126 bolted to a pair of upright posts 128 which are themselves slidingly received in a pair of supports 130 welded to harvester frame 12. The posts 1 28 also carry a pair of brackets 1 32 for a sheet metal guard 134 for transfer device 32.

A sprocket 136 is keyed to shaft 124 and forms part of drive train 44, whereby drum 112 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 138 received on a hexagon shaft 140 which is itself rotatably received in apertures 142 in a pair of flanges 144 welded to frame 12. The lower ends of posts 128 rest on cams 138. Rotation of shaft 140by means of a spanner causes the cams to adjust the clearance between transfer device 32 and primary conveyor 30 from a nominal minimum upto w millimetres. A locking screw 146 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 equaily 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 108. The portions 156 of bars 154 return to their rest position under their own weight.

As shown in Figures 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 168 clamped between a nylon runnerstrip 1 70 (on which primary conveyor 30 runs) and frame 12 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 178 of hopper 36 and is pivotally mounted on frame 12 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.

The 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 174 as shown in Figure 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 1 74-as in the case of bars 1 54.

The other side wall 184 of hopper 36 is in the form of an articulated movable wall pivotally mounted on the frame 12 for movement by means of a double-acting ram 186 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.

Figures 9, 10 and 11 show topping mechanism 24 in greater detail. Figure 9 shows all the components of mechanism 24 and is largely self explanatory in the light of description above of the main parts of the mechanism, and their functions.

It should be noted that there are several small differences between the structures shown in Figure 9 on the one hand, and Figures 10 and 11 on the other hand. These differences are merely matters of shape and configuration do not affect the mode of operation of the mechanism, and should be ignored.

Among components shown in Figure 9 and not specifically mentioned before or not shown in the preceding Figures are: height adjustment means 200 for double acting spring assembly 62, scraper 202 for feeler wheel 58, topper blade 204, a guard 206 for chain drive 52, and a tension spring 208 to bias disc 25 into work.

Now topping mechanism 24 is mounted on arm or frame 54 which is pivotally connected to harvester main frame 12 (pivot axis 60) to permit up and down movement of mechanism 24 (arrow M) to follow the contours of the beet being topped. Spring assembly 62 acts between harvester frame 12 and arm 54 to resiliently resist both up and down movement of the arm during use.

Spring assembly 62 comprises a central spring seat 210, upper and lower spring seats 212 and 214 respectively, a central rod 216, and upper and lower springs 218 and 220 respectively.

Springs 218 and 220 themselves are both coiled compression springs and each is formed of high quality spring wire (of the same quality as car engine valve springs) of gauge 4S.W.G. The springs are of overall length 200 millimetres (with the ends ground square) and with an internal diameter of at least 40 and preferably 50 millimetres.

Central spring seat 210 is double-ended and secured by bolts to height adjustment means 200, which itself comprises a pair of brackets 222, 224 and an upright adjustment member 226 formed with a row of holes 228. Seat 210 is bolted between brackets 222, 224 and positioned, relative to frame 12 by a pair of pins or bolts 230 which pass through holes 228 in adjustment member 226 and holes 232 in brackets 222, 224 which are aligned therewith.

Top spring seat 212 is fixed to a bracket 234 on topper arm 54 and serves to transmit thrust to and from spring assembly 62.

Central rod 21 6 is secured at its upper end by a nut 236 to top spring seat 212 and slides freely through central spring seat 210. The lower end of the rod is formed with a series of transverse holes (not shown) to receive a pin (not shown) whereby lower spring seat 214 (which is received on the rod) can be position-adjusted along the rod to change the degree of pre-loading applied to spring assembly 62.

Double acting spring assembly 62 is capabie of supporting the weight acting thereon both of the topper 24 and of arm or frame 54, with topper 24 clear of the ground, so as to define an equilibrium position of the topper relative to harvester frame 12. In this equilibrium position, spring assembly 62 resiliently resists both upward and downward movement of the topper relative to frame 12 and there is zero weight acting on topper blade 204.

When setting up the harvester 10 to commence a day's work, all that is required is to set skids 28, 29 so that they hold the harvester frame such that lifting wheels 26, 27 are at the required depth. Then to set topper 24, brackets 222, 224 are merely repositioned on adjustment member 226 so that topper blade 204 is just at ground level. No tampering with the setting (compression) of spring assembly 62 is required for this purpose.

In use, spring assembly 62 supports topper 24 so that blade 204 freely follows the contours of the beet crowns and removes the tops. Topped beet are lifted by wheels 26, 27 onto the inlet end 96 of primary conveyor 30 which conveys the roots rearwards while sieved 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 116 towards transfer hopper 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 1 48 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 zero weight topping provided by spring assembly 62 and the simple adjustment of topping height by brackets 222,224 without tampering with springs 218,220, both of which features lead in practice to better beet contour following during use on the farm.

Among modifications which could be made in the above embodiment which are nevertheless within the scope of the invention are the use of any convenient alternative adjustment devices for brackets 222, 224 and lower spring seat 214.

Claims (10)

Claims

1. A sugar beet harvester comprising: a frame; ground wheels to support the frame; root topping means to remove leafy matter from beet to be harvested; the root topping means being mounted on a mounting arm which is pivotally connected to the frame to permit up and down movement of the root topping means relative to the frame; and a double acting spring assembly acting between the frame and the mounting arm to resiliently resist both upwards and downwards movement of the arm during use.

2. A sugar beet harvester according to claim 1 wherein the double acting spring assembly is capable of supporting the weight acting thereon both the root topping means and of the mounting arm with the root topping means clear of the ground, so as to define an equilibrium position of the topping means relative to the frame of the harvester, and in said equilibrium position of the topping means the double acting spring assembly resiliently resists both upward and downward movement of the topping means relative to the frame during use.

3. A sugar beet harvester according to claim 2 wherein the double acting spring assembly is connected to the frame of the harvester by height adjustment means whereby the height of the topping means in its equilibrium position relative to the harvester frame can be adjusted without tampering with the setting of the double acting spring assembly.

4. A sugar beet harvester according to claim 3 wherein said height adjustment means comprises an adjustment member formed with a row of holes and an associated pin to register with the holes.

5. A sugar beet harvester according to any preceding claim wherein said double acting spring assembly comprises two coiled springs.

6. A sugar beet harvester according to claim 5 wherein both of said springs are acting in compression.

7. A sugar beet harvester according to any preceding claim comprising adjustment means to change the preloading applied to said double acting spring assembly.

8. A sugar beet harvester according to claim 5 or claim 6, or claim 7 when dependent upon claim 5, wherein the internal diameter of said coiled springs is at least 40 millimetres and preferably is 50 millimetres.

9. A sugar beet harvester according to claim 1 substantially as described herein and as illustrated in Figures 3, 9, 10 and 11 of the accompanying drawings.

10. Root topping means substantially as described herein and as illustrated in Figures 3, 9, 10 and 11 of the accompanying drawings.