GB2037551A - Soil cultivating implement - Google Patents

Abstract

A soil cultivating implement comprises soil cultivating members (7) that are rotatable about a substantially horizontal axis (4) which extends transverse to the intended direction of operative travel (A) of the implement, said members (7) being partially surrounded by a hood or baffle (9) which hood or baffle (9) has at least one side plate (3), wherein adhesion of soil to the or each side plate (3) is reduced or prevented by providing that side plate with an arcuate flexible element (42) e.g. of canvas and/or rubber. A rigid portion (41) of the or each side plate (3) is preferably formed with an arcuate opening (46) that registers with the corresponding element (42) and portions of a curved wall of the hood or baffle (9) which register with the members (7) are preferably also of flexible formation. <IMAGE>

Description

SPECIFICATION Soil cultivating implements This invention relates to soil cultivating implements of the kind which comprise a plurality of soil cultivating members that are rotatable about a horizontal or substantially horizontal axis which extends substantially perpendicular, or at least transverse, to the intended direction of operative travel of the implement, at least some of said soil cultivating members being partially surrounded by a hood or baffle which hood or baffle also includes at least one side plate.

Known soil cultivating implements of the kind set forth above are subject to progressively increasing power consumption as a result of the build-up of adhering soil on the or each hood or baffle side plate and upon more or less curved portions of the hood or baffle. This creates the problems of uneconomic use of fuel, inefficient operation, and eventual failure of the implement if frequent cleaning operations are not undertaken.

The invention seeks to solve, or at least very markedly to reduce, these problems in an implement of the kind set forth by providing at least said one side plate with at least one flexible element.

For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure lisa plan view of a soil cultivating implement in accordance with the invention connected to the rear of an agricultural tractor, Figure 2 is a side elevation, to an enlarged scale, as seen in the direction indicated by an arrow II in Figure 1, Figure 3 is an opposite side elevation, to the same enlarged scale as Figure 2, as seen in the direction indicated by an arrow Ill in Figure 1 and Figure 4 is a section, to an enlarged scale, taken on the line IV-IV in Figure 3.

Referring to the accompanying drawings, a soil cultivating implement in accordance with the invention is illustrated therein but it is noted that the implement might equally well be called a soil cultivating machine, or merely, a cultivator.

The term "soil cultivating implement" alone is used throughout the remainder of this specification for the sake of brevity. The implement has a mobile frame which comprises lower and upper frame beams 1 and 2 that are both of circular cross-section and both of which extend substantially horizontally transverse, and usually (as illustrated) substantially horizontally perpendicular, to the intended direction of operative travel of the implement that is indicated by an arrow A in Figures 1,2 and 3 of the drawings. It can be seen from Figures 2 and 3 of those drawings that the relatively spaced but parallel frame beams 1 and 2 are at different horizontal levels with the lower frame beam 1 in advance of the upper frame beam 2 having respect to the direction A.The opposite ends of the frame beams 1 and 2 are rigidly secured to opposite side plates 3 of the mobile frame which side plates 3 are both substantially vertically disposed in parallel or substantially parallel relationship with each other and with the direction A, said side plates 3 being located principally, but not entirely, to the rear of the frame beams 1 and 2 relative to the intended direction of operative travel A.

Further details of the frame side plates 3 will be given below.

A cultivating member carrier in the form of a hollow shaft 4 has stub shafts 5 at its opposite ends which stub shafts 5 are rotatably mounted in substantially horizontally aligned bearings which are carried by the frame side plates 3 in such away that said shaft 4 extends substantially horizontally per pendicularto the direction A at a location which, as seen in plan view (Figure 1) is substantially mid-way between the foremost and rearmost extremities of the side plates 3 whereas, as seen in side elevation (Figure 2 or Figure 3), the shaft 4 is considerably closer to the lowermost extremities of the side plates 3 than it is to the uppermost extremities thereof.One of the two stub shafts 5 extends through the corresponding frame side plate 3 into a gear casing 6 which is fastened to the plate 3 concerned and which casing 6 contains parts for transmitting rotary drive to the hollow shaft 4. These transmission parts will be further described below. Groups of cultivating members in the form of rigid tines 7 are secured to the shaft 4 at intervals along the axial length thereof but Figures 2 and 3 of the drawings each show only one of the tines 7 in a somewhat diagrammatic manner. Each group of tines 7 comprises a number of diametrically opposed (with respect to the longitudinal axis of the shaft 4) pairs of the tines 7.

A hollow beam 8 of substantially rectangular cross-section interconnects the opposite side plates 3 of the mobile frame art a location towards the leading edges of those plates 3, with respect to the direction A, and substantially vertically beneath the lower frame beam 1. A leading lower region of a substantially cylindrically curved hood or baffle 9 is fastened to the rear of the frame beam 8 and said hood or baffle 9 extends upwardly and rearwardly around the hollow shaft 4 and its tines 7 to subtend an angle of not less than 90 at the longitudinal axis of the shaft 4.The hood or baffle 9 partially surrounds the shaft 4 and its rigid tines 7 throughout a little more than 90 in the embodiment which is illustrated in the accompanying drawings and the rear edge of said hood or baffle 9, with respect to the direction A, is secured to a bar 10 of angular cross section that interconnects the side plates 3, in parallel relationship with the beams 1, 2 and 8, at a location close to obliquely extending rear edges of those side plates 3. It will be noted from Figure 1 of the drawings that the hood or baffle 9 actually comprises three larger flexible portions 11, two smaller flexible portions 1 1A and four rigid portions 12.All of these portions 11, 11A and 12 are connected to both the beam 8 and the bar 10 and itwill be seen from Figure 1 ofthe drawings that the rigid portions 12 are arranged alternately between the flexible portions 11 or 11 and 11 A and that the two smaller flexible portions 11A are disposed alongside corresponding ones of the two frame side plates 3 whereas the three larger flexible portions 11 are spaced from the side plates 3 and lie between successive ones of the rigid portions 12.Each of the flexible portions 11 and 1 1 A of the hood or baffle 9 is substantially in register with a corresponding one of the groups of rigid tines 7 that are carried by the hollow shaft 4, each such portion 11 and 11A having a length in a direction which is parallel to the longitudinal axis of the shaft 4 that is substantially the same as the working width of the corresponding group of tines 7. It will immediately be appreciated that the groups of tines 7 which lie at opposite ends of the shaft 4 in substantial register with the two smaller flexible portions 1 lA of the hood or baffle 9 are shorter in axial extent along the shaft4than are the groups of such tines 7 which register with the larger flexible portions 11 of the hood or baffle 9.Conveniently, but by no means essentially, the groups of tines 7 which register with the hood or baffle portions 11A comprise substantially half the number of tines 7 that are comprised by each of the groups which registers with a corresponding one of the larger flexible hood or baffle portions 11.

The flexible portions 11 and 1 1A of the hood or baffle 9 may advantageously be formed from strips of canvas and/or rubber, such strips being bolted to the rigid portions 12 of the hood or baffle which rigid portions are conveniently in the form of curved plates. The upper convex surfaces of these spaced plates are connected to one another by three relatively spaced parallel tubes 13, said tubes 13 extending throughout the whole, or substantially the whole, of the effective width of the hood or baffle 9.

The three tubes 13 are, at each end, secured to a corresponding strip 14 and said strips 14 are, in turn, fastened to the respective frame side plates 3. It is noted that the opposite ends of the angular cross section bar 10 are, in fact, indirectly connected to the corresponding frame side plates 3 by respective fastening plates 15, said fastening plates 15 being so shaped that each of them comprises a portion which projects upwardly, and rearwardly with respect to the direction A, beyond the obliquely extending rear edge of the corresponding frame side plate 3. A plurality of clamps which are not shown in the drawings are employed to secure a large number of spring steel rods 16 to the bar 10 which latter extends parallel to the frame beams 1 and 2.The rods 16 are regularly spaced apart from one another along the length of the bar 10, the regular spacing conveniently, but not essentially, having a magnitude of substantially 35 mm. The longitudinal axes ofthe rods 16 are contained in corresponding planes that are all parallel or substantially parallel to one another and to the direction A. Each rod 16 comprises an upper rectilinearly extending portion that projects downwardly and rearwardly with respect to the direction A from the bar 10, the lower end of said portion merging into a downwardly curved portion whose centre of curvature is approximately, but not necessarily exactly, coincident with the longitudinal axis of the hollow shaft 4.It will be seen from Figures 2 and 3 of the drawings that the free lower ends of the rods 16 are located at a level which is substantially the same as, and actually just beneath that of, the longitudinal axis of the hollow shaft 4. The resilient rods 16 together afford a grille or grating.

Two arms 18 are turnably connected to the portions of the corresponding fastening plates 15 which project upwardly and rearwardly from the frame side plates 3 by pivots 17 which are substantially horizontally aligned in a direction which is parallel to the length of the frame beams 1 and 2. The two arms 18 are secured to corresponding ones of two independently pivotable screening hoods or baffles 19 and 20 that are located alongside one another in a horizontal direction that is perpendicular to the direction A with each hood or baffle 19 and 20 comprising a similar substantially cylindrically curved wall.The two hoods or baffles 19 and 20 will tend to turn downwardly, under gravity, about the axis which is defined by the pivots 17 but the positions which they adopt about that axis are governed by the provision, on top of the curved wall of each hood or baffle, of a pair of lugs to which is pivotally connected a corresponding angularly bent rod 21. A chain or the like extends forwardly from the bend in each rod 21 and can be coupled in an adjustable manner to a corresponding bracket (Figures 1 and 3) which is fastened to the frame beams 1 and 2. Each chain co-operates adjustably with a slot at the upper and rearmost end of the corresponding bracket in a manner that is knownperse and the rods 21, chains and brackets together afford variable length suspensions for the two hoods or baffles 19 and 20.The particular positions for the screening hoods or baffles 19 and 20 which will be adopted for any particular cultivating operation will depend upon the nature and condition of the soil that is to be dealt with and the particular purpose for which that soil is required after treatment. The drawings show the hoods or baffles 19 and 20 in positions of adjustment about the axis which is defined by the pivots 17 which are such that the lower edges of their curved walls are at substantially the same horizontal level as is the longitudinal axis of the shaft 4.Helical tension springs 24 interconnect anchorages on the frame side plates 3 and further anchorages on substantially vertical side walls of the two hoods or baffles 19 and 20 and it will be evident from the drawings that said springs 24 tend to maintain those hoods or baffles in the positions of adjustment which are dictated by the variable length suspensions that have been described above, the springs 24, however, being extendable to allow the hoods or baffles 19 and 20 to deflect upwardly during the operation of the implement when large accumulations of soil are dealt with.

Eight flat sheet metal guide members 22 for soil displaced by the tines 7 are arranged at the concave sides of the curved walls of the two hoods or baffles 19 and 20, there being four of the guide members 22 in respect of each of those two hoods or baffles 19 and 20. The general plane of each flat guide member 22 is inclined to the direction A and said guide members can be considered as forming four pairs with the two members in each pair disposed with their general planes symmetrically rearwardly convergent with respect to the direction A. The leading extremities of the guide members 22 are located very close to the grille or grating that is afforded by the spring steel rods 16 (see Figure 2) and the guide members 22 have leading edges which are inclined downwardly and rearwardly from those leading extremities with respect to the direction A.Lower edges of the soil guide members 22 are horizontally or substantially horizontally disposed at the same levels as are the side walls of the two hoods or baffles 19 and 20. Considering the four guide members 22 which correspond to the hood or baffle 19 from left to right as seen in Figure 1 of the drawings, the first one extends obliquely rearwardly from a location in register with the outer end of the small group of tines 7 which corresponds to the respective smal lerflexible portion 1 1A ofthe hood or baffle 9 whereas the second member 22 extends obliquely rearwardly in convergent relationship with the first member 22 from a location which is substantially in register with the centre of the first larger group of tines 7 (considered along the shaft 4 from the left hand end thereof as seen in Figure 1 of the draw ings), said larger group of tines 7 substantially registering with the first larger flexible portion 11 of the hood or baffle 9 which is encountered along that hood or baffle from the left hand end thereof as seen in Figure 1. The leading ends of the second and third members 22 adjoin one another and are secured to a substantially vertical plate (not visible) which is fastened to the inner concave surface of the curved wall of the hood or baffle 19. The third guide member 22 extends obliquely rearwardly from this plate in divergent relationship with the second member 22 and the fourth member 22 extends obliquely rearwardly from a location which is substantially in register with the middle of the central larger group of tines 7, said fourth member22 being in convergent relationship with the third member and parallel or substantially parallel relationship with the second member.The result of this arrangement is that, during operation of the implement, the soil which is displaced by the two smaller and three larger groups of tines 7 is guided rearwardly by the members 22 to form four soil ridges which substantially register, in the direction A, with the positions of the four rigid portions 12 of the hood or baffle 9, the gaps between the lower and rear delivery ends of the four pairs of guide members 22 being in substantially registering relationship with the four rigid portions 12 in the direction A. The implement can thus usefully be employed in forming longitudinally extending but relatively spaced ridges of soil such as are required in the earthing-up of potatoes and other sub-surface crops.

The frame beams 1 and 2 are provided, substantially midway between the general planes of the two frame side plates 3, with a coupling member ortres tle 23 which is of substantially triangular configuration as seen in front or rear elevation. The coupling member or trestle 23 is employed in a manner which is known per se in connecting the frame of the implement to the three-point lifting device or hitch at the rear of an agricultural tractor or other operating vehicle. Such a known connection is illustrated somewhat diagrammatically in Figures 1,2 and 3 of the drawings.That stub shaft 5 at one end of the hollow shaft 4 which projects into the gear casing 6 carries, inside that gear casing, a toothed pinion 25 (Figure 2), the teeth of the pinion 25 being in driven mesh with those of a larger toothed pinion 26 that is rotatable about a stub shaft 27 which is secured to the outer surface of the corresponding frame side plate 3. The teeth of the larger pinion 26 are, in turn, in driven mesh with those of a smallertoothed pinion 28 which is of the same size as the pinion 25. The toothed pinion 28 is secured to one end of a substantially horizontal shaft 29 which shaft 29 projects, from the gear casing 6, through the corresponding frame side plate 3 to extend axially inside a tubular casing 30 which interconnects said side plate 3 and a substantially centrally mounted gear box 31 that is carried by the frame beam 2.The shaft 29 inside the tubular casing 30 is in parallel or substantially parallel relationship with the frame beams 1 and 2. Bevel pinions (not visible) inside the gear box 31 place said shaft 29 in driven connection with a rotary input shaft of the gear box 31 that has a leading end which projects forwardly from the front of the gear box 31 in substantially the direction A. However, a changespeed gear 32 is provided at the back of the gear box 31 with respect to the direction A and the transmission members in the gear box 31 include two shafts having splined ends which project through the back of that gear box into the change-speed gear 32. The splined ends of these two shafts are arranged to co-operate with the matchingly splined hubs of pairs of toothed pinions of different sizes.The output shaft 29 of the gear box 31, and thus the hollow shaft 4, can accordingly be driven at any one of a number of different speeds without having to change the speed of rotation that is applied to the input shaft of the gear box 31, by employing an appropriate pair of toothed pinions in the change-speed gear 32 with said pinions appropriately mounted on the splined shaft ends that have been mentioned above. In this connection, it will be appreciated that the two pinions of each pair are interchangeable on the shaft ends to produce different transmission ratios as well as being exchangeable for at least one other pair of pinions.The forwardly projecting end of the rotary input shaft of the gear box 31 is splined or otherwise keyed to enable itto be placed in driven connection with the power take-off shaft of an agricultural tractor or other operating vehicle of the implement by way of an intermediate telescopic transmission shaft 33, which is of a construction that is known per se, having universal joints at its opposite ends.

The frame beams 1 and 2 are provided, at a short distance inwardly towards the centre of the implement from each side plate 3, with supports which project forwardly beyond the leading lower frame beam 1 by some distance. Each support has a corresponding substantially horizontally forwardly projecting arm 34 secured to it and the leading end of each arm 34 is provided with a corresponding sub stantiallyvertically disposed sleeve 35 of square cross-section. Each sleeve has a corresponding sub stantiallyvertically extending wheel carrier 36 of square cross section entered adjustablythrough it and it will be apparent from Figures 2 and 3 of the drawings that each ca rrier 36 is formed with a row of regularly spaced apart transverse holes 38 whereas the upper end of each sleeve 35 is formed with two pairs of transverse holes 40, which are preferably spaced apart from one another by a different distance to the spacing between the holes 38, horizontal locking pins 39 (or equivalent bolts) being provided for entry through chosen ones of the holes 40 and chosen registering holes 38 to maintain the wheel carriers 36 in corresponding positions of downward extension beyond the lower ends of the two sleeves 35.The lower ends of the two wheel carriers 36 are provided with corresponding outwardly projecting horizontal axles upon which pneumaticallytyred ground wheels 37 are rotatably mounted. It will be apparent from Figures 2 and 3 of the drawings that the level at which the axis of rotation of the ground wheels 37 is set relative to the level of the frame of the implement principally determines the working depth of the groups of tines 7 which are carried by the hollow shaft 4.

The frame side plate 3 that is remote from the gear casing 6 comprises a rigid plate-formation portion 41 and, similarly the side plate 3 to which the gear casing 6 is secured comprises a rigid plate-formation portion 41 A. The two portions 41 and 41 A have different shapes in their upper regions (compare Figures 2 and 3 of the drawings), said portions 41 and 41A being connected to the frame beams 1,2 and 8 and to the bar 10 as described above. However, the inner surfaces of the two portions 41 and 41 A that face one another are provided with corresponding arcuately curved (see Figure 3) flexible elements 42, the centre of curvature of each element 42 being coincident, or substantially coincident, with the longitudinal axis of the shaft 4.Each flexible element 42 is advantageously, but not essentially, formed from canvas and/or rubber and the upper convex edges thereof are advantageously located very close to the cylindrically curved edges of the respectively neighbouring smaller flexible portions 1 1A of the hood or baffle 9. Each arcuately curved flexible element 42 preferably subtends an angle of substantially 180 at the longitudinal axis of the shaft 4 although it can be seen in Figures 2 and 3 of the drawings that, in the embodiment which is being described, the two elements 42 actually subtend marginally less than 180 at said axis.As shown in Figure 4 of the drawings, the upper and outer convexly curved edge of each element 42 is preferably disposed a little further from the longitudinal axis of the hollow shaft 4 than is the convex surface of the respective closely neighbouring hood or baffle portion 11A. The two elements 42 are so disposed around the longitudinal axis of the shaft 4 that the leading ends thereof with respect to the direction A are at a lower horizontal level than are their rear ends.

As can be seen best in Figure 4 of the drawings, the opposite ends of each flexible element 42 are passed through slots 43 in the portions 41 and 41 of the corresponding side plates 3 so that said ends lie alongside the surfaces of the two plate-formation portions 41 and41Awhich are relatively remote from one another. The elements 42 are secured to the respective portions 41 and 41 A at locations alongside the slots 43 by pairs of bolts 45 and are also secured to the same rigid portions of the side plates 3, but at the opposite sides of the slots 43, by groups of three bolts 44.It will be seen from Figure 4 of the drawingsthatthe bolts 45 secure the elements 42 to the inner surfaces of the plate portions 41 and 41 A which face towards one another whereas the bolts 44 secure said elements to the outer surfaces of the plate portions 41 and 41A which are relatively remote from one another.Each flexible element 42 is located wholly or principally in register with the upper half of the circular path of movement of each group of tines 7 around the longitudinal axis of the shaft 4 as viewed in a direction parallel to that axis (Figure 2 or Figure 3) and each arcuate element 42 has a radial extent between its inner and outer edges which is substantially 50% of the radial extent from said axis of the circular paths which are traced by the tips of the tines 7 when the implement is in operation. The plate-formation portion 41 of the frame side plate 3 which is remote from the gear casing 6 is formed with an arcuate opening 46 (Figures 3 and 4) which registers in position with the corresponding element 42 but which is of smaller size than that element.The arcuate opening 46 has a radial extent between its inner and outer edges which is advantageously substantially 40% of the radial extent from the longitudinal axis of the shaft 4 of the circle which is traced around that axis by the tips of the tines 7 during the operation of the implement. The arcuate opening 46 advantageously subtends an angle of substantially 140 at the longitudinal axis of the shaft 4 and, as can be seen in Figures 3 and 4 of the drawings, its opposite ends are spaced from the corresponding pair of slots 43 leaving regions of the plate portion 41 for the reception of the corresponding pairs of bolts 45.An arcuate opening corresponding to the opening 46 is not formed in the portion 41A of the side plate 3 to which the gear casing 6 is secured in the embodiment which is illustrated in the accompanying drawings but it is noted that, if desired, the shaft 29 and the associated stub shaft 5 could be lengthened and a gear casing or gear box equivalent to the gear casing 6 could be provided in spaced relationship with the neighbouring frame side plate 3. Under these circumstances, the side plate portion 41A could then be formed with an arcuate opening equivalent to the opening 46 in the side plate portion 41. It is not essential that the or each opening 46 should be of precisely arcuate shape.It could equally well be generally banana-shaped or could be replaced by a series of holes in the corresponding plate-formation portion instead of a single opening, provided that said holes are large enough to enable the adjoining flexible element 42 to move into and out of those holes and laterally relative thereto to some extent.

The soil cultivating implement that has been described with reference to the accompanying drawings has a working width of substantially 3 metres and, as mentioned above, is particularly intended for use in earthing-up rows of potato plants or other sub-surface crops. Before work commences, the depth to which the tines 7 are to penetrate into the soil is adjusted by moving the ground wheels 37 upwardly or downwardly, as may be required, relative to the frame of the implement employing the sleeves 35 and wheel carriers 36 as described above and maintaining any chosen depth setting by engaging the locking pins 39 in the chosen holes 40 and the chosen registering holes 38.The speed at which the shaft 4 will rotate in response to a more or less standard speed of driving rotation that is applied to the leading end of the rotary input shaft of the gear box 31 is dictated by selecting an appropriate gear ratio in the change-speed gear 32 having regard to the nature and condition of the soil that is being dealt with and factors such as the stage of progress of the potato plants or other plants that are to be earthedup. The implement is moved over the rows of plants in such a position that the groups of tines 7 register with the spacing strips between those rows, it being noted that the wheels of the agricultural tractor or other operating vehicle and the depth control ground wheels 37 of the implement also register with such spacing strips.The shaft 4 and its groups of tines 7 revolve in the direction that is indicated by an arrow B in Figures 2 and 3 of the drawings and each group of tines 7 displaces in that direction a quantity of soil that is dependent to a considerable extent upon the pre-setworking depth of the implement. The displaced soil is moved upwardly and rearwardly beneath the hood or baffle 9 and is then thrown againstthe grille or grating of spring steel rods 16. Hard lumps of soil, stones, root debris, weeds and the like will not pass through the gaps between the rods 16 and are therefore guided downwardly and rearwardly along those rods to fall into the bottoms of the furrows that were excavated by the corresponding groups of tines 7.Most of the finely divided soil, however, passes readily through the gaps between the rods 16 and is therefore thrown into engagement with the concave surfaces of the curved walls of the two hoods or baffles 19 and 20 and/or into contact with the guide members 22 which are carried by those surfaces. As previously described, the eight guide members 22 form four rearwardly divergent pairs which guide the finely divided soil into four strips which register, in the direction A, with the rigid portions 12 of the hood or baffle 9 and thus with the rows of potatoes or other plants that are growing in the land which is being treated.Four relatively spaced ridges of soil that extend parallel to the direction A are thus formed on top of the growing potato or other plants and any already existing ridges are repaired and augmented in size, said ridges being formed substantially wholly from finely divided soil which will not interfere with the continuing growth of the plants. It will be appreciated that the carriage of the displaced soil by the tines 7 around the shaft 4 beneath the hood of baffle 9 tends to crumble that soil to a considerable extent so that the greater part thereof usually passes between the rods 16 when previously worked agricultural land is being dealt with. The heights of the soil ridges which are formed or augmented by the implement can be adjusted by shortening or lengthening the suspensions of the two screening hoods or baffles 19 and 20 in the manner which has been previously described above.The flexibility of the hood or baffle portions 11 and 1 1A prevents the earth that is displaced by the respectively registering groups of tines 7 from adhering to the curved surface of said hood or baffle 9 to any significant extent or for any significant length of time.

In addition to a tendency for soil to adhere to the hood or baffle 9 in the regions thereof which are in register with the groups of tines 7, there is a strong tendency for soil to adhere to the upper regions of the frame side plates 3 near the hood or baffle 9 and the provision, in accordance with the invention, of at least one of the flexible elements 42 very greatly reduces the incidence of soil adhesion to the corresponding frame side plates 48 and substantially eliminates such adhesion in many cases. When the flexible elements are arranged alongside the arcuate openings 46 or other openings of equivalent effect, the tendency of soil to adhere to the elements 42 is still further reduced since said elements can move inwardly and outwardly through the openings 46 performing, under some circumstances, a more or less vibratory movement.Instead of being merely in closely neighbouring relationship with the smaller flexible portions 1 1A of the hood or baffle 9, the flexible elements 42 of the frame side plates 3 may actually be directly joined to said portions 11 A in which case the resilient deflections of the united portions 1 1A and elements 42 will be related to one another. It has been found that it is most important to prevent soil adhering to the frame side plates 3 and to the hood or baffle 9 where the tines 7 are moving upwardly adjacent to those parts, and accordingly the flexible elements 42 of the side plates 3 need only be furnished throughout a restricted arc around the longitudinal axis (axis of rotation) of the shaft 4.

The provision of the flexible elements 42 and the flexible portions 11 and 1 1A of the hood or baffle 9 very greatly reduces, if not completely eliminates, a progressively increasing power consumption of the implement to keep the shaft 4 and its tines 7 rotating at the required speed as frequently occurs in basi cally similar prior art implements that do not exhibit the features of the present invention. Apart from being wasteful of fuel, it will be realised that, unless fairly frequent major cleaning operations are undertaken with such prior art implements, the resistance to rotation of a shaft that is equivalent to the shaft 4 and of cultivating members that are equivalent to the tines 7 which is caused by the build up of adhering soil will lead to breakdown of the implement, probably as the result of a fracture of an overloaded transmission part. The use of rubber for the elements 42 and for the portions 11 and 1 1A of the hood or baffle 9 has the advantage that the surfaces of those parts to which soil would tend to adhere are smoother than when canvas is employed and the use of rubber may accordingly be preferable particu marly when heavy soils of a sticky nature are primarily to be dealt with. However, it is emphasised that flexible materials other than canvas and/or rubber may be employed, some synthetic plastics materials, in particular, being suitable for the formation of the parts 11, 11Aand42.

Although various features of the soil cultivating implement that have been described and/or that are illustrated in the accompanying drawings will be set forth in the following claims as inventive features, it is emphasised that the invention is not necessarily limited to those features and that is includes within its scope each of the parts of the soil cultivating implement that has been described, and/or that is illustrated in the accompanying drawings, both indi vidually and in various combinations.

Claims (20)

1. Asoil cultivating implement which comprises a plurality of soil cultivating members that are rotat able about a horizontal or substantially horizontal axis which extends substantially perpendicular, or at least transverse, to the intended direction of operative travel of the implement, at least some of said soil cultivating members being partially surrounded by a hood or baffle which hood or baffle also includes at least one side plate, wherein at least said one side plate is provided with at least one flexible element.

2. An implement as claimed in claim 1, wherein the or each flexible element of the or each hood or baffle side plate is carried by a rigid portion of the same side plate.

3. An implement as claimed in claim 2, wherein the or each flexible element is located wholly or principally in a region of said side plate which registers with the upper half of the circular path which the soil cultivating members trace about said horizontal or substantially horizontal axis during the use of the implement.

4. An implement as claimed in claim 2 or 3, wherein, when viewed lengthwise of the horizontal or substantially horizontal axis of rotation of the soil cultivating members, the or each flexible element is of arcuate shape.

5. An implement as claimed in claim 4, wherein the centre of curvature of the outer convex edge of the or each flexible element is coincident with the horizontal or substantially horizontal axis of rotation of the soil cultivating members.

6. An implement as claimed in claim 4 or 5, wherein the or each flexible element subtends an angle of substantially 180 at the horizontal or sub stantiaily horizontal axis of rotation of the soil cultivating members.

7. An implement as claimed in any preceding claim, wherein the or each flexible element extends radially with respect to the horizontal or substantially horizontal axis of rotation of the soil cultivating members to a location beyond that of a more or less curved wall of the hood or baffle.

8. An implement as claimed in claim 7, wherein at least one portion of the more or less curved wall of the hood or baffle which substantially adjoins the flexible element of at least said one side plate of that hood or baffle is also of flexible formation.

9. An implement as claimed in claim 8, wherein the or each flexible element is located in very close proximity to, or is actually united with, a corresponding flexible portion of the more or less curved wall of said hood or baffle.

10. An implement as claimed in claim 2 or any one of claims 3 to 9 when read as appendant to claim 2, wherein the rigid portion of the or each hood or baffle side plate is formed with an opening which is closed by the flexible element or corresponding flexible element.

11. An implement as claimed in claim 10, wherein the or each opening is arcuate in shape.

12. An implement as claimed in claim 11, wherein the or each arcuate opening subtends an angle of substantially 140 at the horizontal axis of rotation of the soil cultivating members, and wherein the leading end of the or each arcuate open ing with respecttothe intended direction of operative travel of the implement is located at a lower horizontal level than is the rear end thereof.

13. An implement as claimed in claim 11 or 12, wherein the radial extent of the or each arcuate opening, measured from its inner curved edge to its outer curved edge and with respect to the horizontal or substantially horizontal axis of rotation of the soil cultivating members, is substantially 40% of the radial distance from that axis of the outermost ends or tips of said soil cultivating members.

14. An implement as claimed in claim 2 or in any one of claims 3 to 13 when read as appendantto claim 2, wherein that surface of the or each flexible element of the or hood or baffle side plate which faces the soil cultivating members is closer to those members than is the similarly disposed surface of the or each rigid portion of the or each side plate.

15. An implement as claimed in claim 14, wherein the or each flexible element is secured to the outer surface of said rigid portion of the corresponding side plate that faces away from the soil cultivating members.

16. An implement as claimed in claim 4 or in any one of claims 5 to 15 when read as appendantto claim 4, wherein the or each flexible element is secured to the rigid portion of the corresponding hood or baffle side plate only at substantially the opposite ends of its arcuate shape.

17. An implement as claimed in any preceding claim, wherein the or each flexible element is made from canvas and/or rubber.

18. An implement as claimed in any preceding claim, wherein said hood or baffle has two opposite side plates both of which are provided with at least one flexible element.

19. An implement as claimed in any preceding claim, wherein means is provided to drive the soil cultivating members about said horizontal or substantially horizontal axis in such a direction that, during operation of the implement, those members move generally forwardly through the soil with respect to the direction of travel of the implement at the time, and wherein the or each flexible element is located principally in a region of the corresponding side plate alongside which at least some of the soil cultivating members move upwardly during their rotation about said axis.

20. Asoil cultivating implementofthe kind set forth, substantially as hereinbefore described with reference to the accompanying drawings.