WO1988007812A1

WO1988007812A1 - Crop engaging apparatus

Info

Publication number: WO1988007812A1
Application number: PCT/GB1988/000281
Authority: WO
Inventors: Wilfred Erwin Klinner
Original assignee: Klinner Wilfred E
Priority date: 1987-04-16
Filing date: 1988-04-13
Publication date: 1988-10-20
Also published as: GB8709200D0

Abstract

The crop engaging apparatus for conveying and/or treating crops, particularly forage crops, comprises a rotor (1) mounted for rotation and movement over the ground in a mobile support structure, front covers (3 and 4) and top cover (6) forming with rotor (1) crop flow passage (2). Secured by axial fastening means to the hollow rotor core member (12) of rotor (1) is a plurality of outwardly extending crop engaging elements (11), each element comprising at least one outwardly extending arm and a base portion with abutment regions for cooperation with an abutment surface on the rotor core member (12). Biasing and yielding means and effects are provided, so that the elements (11) maintain or attain in operation the required operating position, by the combination of the material from which the elements are made and the conformation of the outwardly extending arms. The apparatus may be combined with a mower to treat the crop before, during or after cutting.

Description

CROP ENGAGING APPARATUS

The present invention relates to crop engaging apparatus. The invention is concerned in one aspect with apparatus for the condititoning of crops, especially, but not exclusively, grasses before or when they are cut and is concerned in other applications with collecting crop from the ground for harvesting it or for treating and returning it to the ground for drying prior to subsequent harvesting.

Crop treatment and collecting devices employing high-speed rotors having outwardly extending crop engaging elements in the form of laterally inclined arms or of brush tufts have been disclosed previously, in several forms by the present inventor. Particular examples of such disclosures are to be found in patents and applications Nos. UK 1,322,165, GB 204171B, GB 2107963A, GB 2132A62A, GB 2169184A, and GB 2172182A. The main object of such devices is to modify the surface of forage plants, particularly the cuticular layer, by mechanical actions which may include beating, bending, bruising, lacerating, scratching, scuffing, splitting and tearing. In consequence of these forms of treatment the cell moisture of the plants moves more easily to the surface and evaporates more rapidly to atmosphere.

In prior disclosures conditioning devices are relatively complicated in construction and expensive to manufacture, and in practice the crop engaging elements are often unnecessarily long. Hitherto slender and laterally inclined elements needed to be made of sufficiently stiff material to prevent undesirable deflection of the tip regions due to centrifugal effect. Such elements were held captive at their base region in mounting brackets, and to prevent failure in operation the brackets had provision for limited yielding in the general direction of crop flow.

In one aspect the present invention is concerned with providing outwardly extending, resilient crop engaging elements for treating cut or uncut crop, the elements being shaped and mounted to maintain or attain their required operating position and orientation, yet allow momentary yielding along their length, and being relatively simple and inexpensive to manufacture, to fit and to maintain. Considering now another aspect of the invention concerned with conditioning cut crop, it is known that the treatment effect can be enhanced by cooperation of the crop engaging elements with the front part of the conditioning rotor cover. In several of the many forms of green forage crop conditioner the leading edge of the rotor cover may be adjusted fore and aft relative to the tip envelope of the rotor and in or against the direction of rotation. Alternatively, the whole or part of the front section of the rotor cover may be pivoted near the leading edge so that the trailing region of the pivoted section may be moved closer to the tip envelope of the rotor, to form a funnel leading to a transverse restriction of the crop flow passage. Whilst varying the severity of treatment, such arrangements make little contribution to the presentation of the crop in, and the architecture of, the swath placed on the ground at the rear.

Considering now the aspect of the invention concerned with collecting cut crop from the ground for harvesting it or for treating and returning it to the ground, there have been prior disclosures of pick-up rotors employing outwardly extending crop engaging elements, commonly known as tines. Some such crop conveying elements are U-shaped tines as disclosed in German patent No. 690268 (Lythal) and in UK patent No. 198256 (Martin). In both cases a bolt and spring arrangement allows the tine to pivot away from its operating position by compression of the spring. This form of coupling is complicated, expensive to manufacture, and is unsuitable for modern crop conveying and conditioning applications. In many crops the tines give poor pick-up performance because they are made of relatively thin metal rods which normally lie in radial planes normal to the transverse rotor axis.

Another form of high-speed pick-up rotor, as disclosed for example in GB 2130864B and US 4,581,880, employs transverse arrays of planar plastic crop engaging elements. An incidental aspect of these is a pronounced fan effect, which can have undesirable consequences, particularly in dry crops.

According to the present invention there is provided apparatus for conveying and/or treating crop comprising: a mobile support structure for movement over the ground; a rotor mounted for rotation relative to the support structure with its axis of rotation substantially parallel or normal to the ground, the rotor comprising a core member and a plurality of outwardly extending elements for engaging the crop; drive means for driving the rotor in rotation to engage the crop; each crop engaging element being formed of resilient material and comprising at least one outwardly extending arm and a base portion, the element being shaped and mounted to maintain or attain in operation the required operating position, wherein crop engaging edges lie transversely inclined to a radial plane normal to the axis of rotation, or to return to the operating position after yielding at regions along the effective length .of the element in directions including transverse to the direction of rotation.

The present invention finds application in tractor-mounted or tractor- drawn machines which are used in the conservation of grass and other crops for winter feeding to livestock and in the management of grassland areas for amenity and other purposes. In one application, apparatus embodying the invention may be combined with a mower to form a mower- conditioner of generally known configuration. In such a device it is usual to cut the crop by established means, usually horizontally rotating high-speed knives, and then to direct it into the conditioning means for physical treatment aimed to accelerate the rate of moisture loss during a period of exposure of the crop to the ambient conditions on the surface of the field. Alternatively the apparatus of the invention may be attached to a tractor or combined with a mower in such a way that all or some of the crop is treated by the rotor before it is cut.

In a second application the invention may be used to provide means for lifting cut crop from the ground, teasing it out, optionally applying physical conditioning, and replacing the crop on the ground in clearly defined swaths or in spread form. Such re-structuring of the crop as it lies in the field further accelerates the drying process.

In a third application embodiments of the present invention may be used as a pick-up for lifting crop off the ground and conveying it into a windrow or into a harvesting machine, such as a forage harvester, baler or combine-harvester of known construction.

Conditioning of cut crop takes place mainly during first impact contact with the crop engaging elements and whilst the crop is being accelerated and impelled, -usually against the frictional resistance of a rotor cover which may surround at least the second crop engaging quadrant of the rotor. When severe conditioning of cut crop is required, the rotor is driven at high speed and the resistance offerd by the guide means needs to be high. Conversely, gentle crop treatment requires low rotor speeds and low resistance values.

In accordance with one preferred feature the present invention is concerned with the articulation of the front part of a cover for a hori¬ zontal rotor which is driven in the overshot mode, that is to say in a direction to move the crop engaging elements upwards at a front region. It is concerned also with the shape and construction of the crop facing surface of the front part of such a cover. Conveniently the entry section of the front cover may consist of a horizontally hinged hollow or profiled member for guiding the crop into the passage between the rotor and the crop engaging elements. In cross-section the tubular member may be of circular, triangular or other shape, and there may be provided means for adjusting and locking the member in alternative positions.

Preferably the adjacent downstream section of the cover surrounds a major portion of the front of the rotor and is attached to a top cover by means of hinges at the lower and upper edge of an intermediate transverse plate or by means of a flexible linking piece. This articulation arrangement may be combined with locking facilities, to enable the front cover section to be set close to the conditioning rotor periphery throughout the curvature of the section, or at the leading or trailing regions.

Preferably the crop facing surface of the adjustable section of the front cover is shaped to provide a pronounced washboard effect by which crop being impelled through the passage between the section and the conditioning elements is intermittently obstructed in its flow by a succession of transversely opposing and outwardly reclined surfaces forming restrictions and relief spaces. This effect increases the conditioning treatment imparted by the crop engaging elements and also causes stems and other crop matter to be turned and to become scrambled and interlaced when deposited on the ground behind the rotor.

Conveniently in some embodiments a horizontal rotor may be driven in the undershot mode, so that the crop engaging elements are moved downwards at a front region. This is particularly effective when the rotor is positioned to condition uncut crop marginally ahead of a rotary mower, so that the crop is deflected towards, and is supported against the action of, the cutting knives. In such embodiments a front cover serves mainly to protect the crop against premature contact with the crop engaging elements.

Preferably the core member of the rotor is a hollow member of circular or polygonal cross-sectional shape. A polygonal cross-section tube permits the elements to be mounted so that the appropriately shaped base portion of an element straddles an edge of the core tube. Preferred axial fastening means which may be used to secure the elements to the rotor core member have a principal axis which extends through the base portion of the element in an outward direction from the core member towards the region of crop flow. Each crop engaging element and the core member have co-operating abutment regions so shaped and dimensioned to prevent rotation of the crop engaging element away from its required operating position.

Conveniently some or all of the crop engaging elements may be reclined relative to a radius passing through the base of an element, to reduce the load on the fastening device and to discourage crop from adhering to the element. Conveniently also, each element may be secured to the rotor core member by a combination of the said axial fastening means and, spaced from the axial fastening means, a projection extending from the said base portion into the cooperating surface on the rotor core member.

In accordance with another aspect of the invention there is provided a crop engaging device for conveying and/or treating crop, the device comprising a core member and, secured to the core member, a plurality of outwardly extending elements for engaging crop flowing past, or conveyed by the device, each crop engaging element cromprising a member formed of resilient material and shaped to form two outwardly extending arms which may diverge from each other in the outward direction and in a plane generally transverse to the direction of intended movement of the arms with or relative to the crop, the said member also being shaped to form a base portion linking the two arms and adapted to be secured to the cooperating surface on the rotor core member. In the case of arms diverging from each other in the outward direction, each arm may be shaped to resist deflection of the tip region towards the other arm of the element under the effect of centrifugal force.

According to a preferred feature, each diverging arm has a cross-section which tapers towards the crop engaging leading edge of the arm and/or has a groove running along the length of the arm on the side which faces away from the other arm.

In accordance with another preferred feature, it may be arranged that the cross-section of each arm tapers in the outward direction from a rectangular, square or parallelogram-shaped section near the base to a triangular section at the tip.

In accordance with yet another preferred feature, two diverging arms may have laterally inclined crop facing surfaces so that In the direction of rotation they form an open funnel, generating in operation an aerodynamic effect which tends to counteract the centrifugal effect by urging the arms away from each other. This is of particular advantage where the effective length of the arms of crop engaging elements needs to be substantial, for example for penetrating deep layers of crop or when there is a high risk of contact with the ground or with foreign objects of substantial size.

Conveniently for some applications a crop engaging element may comprise one or more arms having a common base portion, two or more arms extending outwardly substantially parallel to each other. Pairs of plain arms may be shaped to have laterally inclined crop facing surfaces forming an open funnel in the direction of rotation. The aerodynamic effect generated and crop impinging upon and passing through the funnel tends to force the arms apart so that they operate in the intended laterally inclined orientation.

Conveniently each arm may divide in its outer region into two or more fingers of equal or different length. The fingers may be shaped to be parallel-sided or convergent towards their tips and/or to be reclined relative to the arm. Preferably the crop engaging edges of arms or fingers are transversely inclined to lie at an angle to the direction of crop flow.

Preferably in cross-sectional shape the arms and fingers of crop engaging elements resemble fins which extend further in the direction of rotation than normal to it. Conveniently there may be provided near the base regions of arms of crop engaging elements grooves or other forms of recesses to reduce the cross-sectional area at that region so as to facilitate lateral yielding or to induce preferential yielding to either side or to one side only.

Similarly there may be provided in trailing edge regions of outwardly extending arms and/or fingers shaped recesses to facilitate yielding by reducing the resistance to rearward deflection.

Conveniently in the fastening of crop engaging elements of the present invention to the cooperating surface on the rotor core member, for example by means of axial bolts, screws or proprietary self-locking in¬ sert fasteners, there may be provided washers or cover plates between the head of the fastening device and the upper surface of the base portion of each element. In tightening down the fastening device, the washer or plate serves to spread the load and to force the shaped abutment region, or regions, of the element into intimate, firm contact with the curved or otherwise profiled cooperating surface on the rotor core member.

A preferred fastening arrangement comprises a rigid, saddle-shaped pressing, moulding or fabricated component which bridges the linking base portion of crop engaging elements fore and aft and has leading and trailing flanges for engaging the rotor core member. In some embodiments ^■ the pressing may surround all but the sides of the base portion of an element. In tightening down the head of the axial fastening means on to the saddle-shaped pressing, the base portion of an element Is firmly gripped, yet prevented from being squashed or distorted, and the spaced- apart leading and trailing flanges become tightly pressed and locked against the surface of the core member. Thus, a single fastening device is able to hold two or more crop engaging elements in position and prevent them from rotating about the axial fastener, even under arduous operating conditions.

Conveniently crop engaging elements of the present invention may be moulded from resilient material in transverse or circumferential arrays so that they are joined together by a common base strip shaped to hug the cooperating surface on the rotor core when the elements are secured by fasteners spaced along the length of each strip.

To save the cost of tapping the rotor core or welding nuts or bolts into position for securing elements directly to the surface of the rotor core, a length of wood or other material sof er than steel may be attached by spaced screws to the inside of the core tube so that it is aligned with any transverse row of fastening holes. It then becomes possible to use wood screws or self-tapping bolts to secure the elements to such battens.

For some purposes and applications preferred fastening means may comprise a rib extending inwardly from the abutment surface of the base region of the crop engaging element, the rib being shaped to be pressed into a slot of equal width but shorter circumferentially extending length provided in the cooperating surface on the rotor core member. Protruding lugs or shoulders at the leading and trailing ends of each fastening rib lock the element in position circumferentially, and on both sides the laterally extending base portion provides transverse stability.

In accordance with yet a further preferred feature, the crop engaging elements may be formed to have a short effective length extending into the crop flow region, relative to the diameter of the rotor core, preferably in the ratio of 1:2 to 1:6, most preferably 1:4. This feature favourably affects the cost of the elements, reduces the fan effect of the rotor and minimises risk of transversely inclined tip portions of elements being deflected by centrifugal effect, particularly at high rotational speeds of the rotor.

Preferably the said crop engaging elements are made of synthetic plastics material, particularly polyurethane, of natural or synthetic rubbers or of other compounds or polymers having suitable flexibility and adequate wear and impact resistance characteristics.

The invention finds particular but not exclusive application where the said elements are made of flexible resilient material for treating grass or other forage crops. The crop engaging device finds application either in the form of a vertical or horizontal rotor for conveying or conditioning crop by rotation of the rotor, or in the form of a stationary device positioned to engage crop flowing or being propelled past the device.

After yielding the elements may be returned to their intended operating positions by a combination of the yielding and biassing arrangements and effects described.

Crop engaging devices embodying the invention may be provided which are applicable to conditioning, tedding, turning, windrowing, scoring, threshing or otherwise treating cut or uncut crops. The present invention provides, at least in preferred embodiments thereof, a number of advantages over previously known crop engaging elements for conveying or for treating crop. Although the crop engaging elements of the invention may be produced from other materials, it is particularly preferred that the elements are made of such resilient or flexible materials which have the advantages of lightness, toughness, low risk of damaging following machinery if lost, and of simple and easy fitting to the surface of a rotor core member.

Εiτιbodiments of the invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 is a diagrammatic cross-sectional side elevation, partly in section, of an apparatus embodying the invention;

Figure 2 is a diagrammatic side elevation of a crop engaging ele¬ ment shaped in the base region to be secured to a tubular rotor core, and Figure 2a is a rear elevation of the crop engaging element of Figure 2;

Figure 2b shows a section in the direction of arrows AA in Figure 2a;

Figures 2c, 2d, 2e, and 2f show alternative sections through the arms of the element in Figure 2a in the direction of arrows BB;

Figure 2g is a perspective view of one arm of a crop engaging element;

Figure 3 is a diagrammatic side elevation, partly in section, of part of a further form of crop engaging element secured by an axial bolt to a rotor core member of polygonal cross-section;

Figure 4 is a diagrammatic rear elevation of a further alternative form of crop engaging element embodying the invention;

Figure 5 is a diagrammatic plan view of the element of Figure 4;

Figure 6 is a diagrammatic plan view of an alternative form of crop engaging element having a shaped fin for locating and securing the element to a core memberj

Figure 7 is a diagrammatic side elevation, partly in section, of a crop engaging rotor provided with two forms of crop engaging element embodying the invention;

Figure 8 is a front elevation, partly in section, of two different crop engaging elements, showing the axial fastening arrangement;

Figure 9 is a front elevation, partly in section, of crop engaging elements with multiple fingers secured to the rotor core by means of a rigid saddle-shaped component;

Figure 9a is a side elevation, partly in section, of the elements In Figure 9;

Figure 10 is a front elevation of fingers of alternative shape in the outer region of a crop engaging element;

Figure 11 is a front elevation of the outer part of a crop engaging element having lateral extensions normal to the outwardly extending arm;

Figures 11a and lib are respectively a side elevation and plan view of the element of Figure 11, and

Figure 12 is a diagrammatic side elevation of a crop engaging rotor embodying the invention and operating in a substantially horizontal plane.

Throughout this specification corresponding components of the various arrangements have been given identical reference numerals. For brevity and simplicity the functions and inter-relationships between the various components are described and explained only when they are first mentioned and not fully in connection with each subsequent figure. Thus it is to be appreciated that each time corresponding components with identical reference numerals are referred to, the appropriate description applies.

Referring first to Figure 1, there is shown a diagrammatic cross- sectional side elevation of an apparatus embodying the invention. The crop engaging rotor shown generally at 1 has a horizontal axis and is carried on a mobile frame (not shown) for movement over the ground. Rotor 1 comprises the tubular rotor core member 12 and a multiplicity of crop engaging elements 11 mounted in transverse arrays upon the rotor core member. Crop, which may have been cut in advance or by a mower (not shown) immediately preceding the rotor 1 in a combined mower-conditioner, is engaged by the rotor at the lower front quadrant, to receive the intended treatment due to impact by, and slip relative to, the crop engaging elements 11.

The elements lift, accelerate and convey the crop upwards into the passage 2 formed between rotor 1 and sections 3, 4, 5 and 6 of a rotor cover arrangement extending at least over the upper front quadrant of the rotor. At the entrance to passage 2, hinged hollow section 3 is angularly adjustable to form an open or restricted entrance region. Front cover section 4 is joined to upper cover 6 by intermediate double- hinged plate 5, to enable front section 4 to be secured by a locking arrangement of known form so that throughout its length it may be equidistant from the tip envelope of rotor 1, or the leading region may be spaced further from or closer to the tip envelope than the trailing region.

The inner surface of front cover section 4 may be provided with a succession of transverse ribs 7, giving a pronounced washboard effect. The leading faces of ribs 7 may be inclined to oppose the flow of crop, and the trailing surfaces may be reclined to form a succession of restrictions and relief spaces. This form of construction Increases the treatment effect by retarding crop and re-directing it repeatedly towards the crop engaging elements, and it causes any alignment of stems to be thoroughly disturbed and all crop matter to become randomly arranged.

Upper section 6 of the rotor cover is provided and shaped to guide the treated crop rearwards, and an adjustable plate or rake 8 may be angled to deflect the crop stream more or less abruptly on to the ground. Laterally effective deflectors (not shown) may be provided optionally, to form the treated material into swaths of variable width or to spread it over the ground.

In alternative embodiments a crop cutting mechanism may be combined with the apparatus shown in Figure 1. The position of such a mower may be in front of, beneath or behind rotor 1 so that all the crop, some of it or none of it can be treated before it is cut. Especially when some or all of the crop being treated is uncut, driving the rotor to operate in the undershot mode can be advantageous in that the crop is oriented and supported by the crop engaging elements in such a way that the cutting performance of the associated mower is enhanced.

In yet other applications one or more short rotors embodying the invention may have vertical or near-vertical axes to engage crop lying on the ground, crop flowing from a mower, or crop before it is cut. Con¬ veniently, a multi-disc mower may have arranged above and slightly forward of the cutting discs rotors operating in parallel planes and being driven to rotate counter to the direction of rotation of the cutting discs. Thus the crop may be physically treated before it is severed from the root system and is inclined and supported counter to the direction of movement of the cutting knives. An advantage of treating uncut crop is that the severity of treatment which may be achieved can be substantially higher than with uncut crop.

In Figures 2 and 2a element 11 comprises two outwardly extending arms 13 and 14 which diverge from each other in the outward direction and in a plane tansverse to the direction of intended movement of the arms. In Figure 2 the intended movement is from left to right, as shown by the arrow, and the arms diverge as shown in Figure 2a. The crop engaging element is formed as a single member with a base portion 15 linking arms 13 and 14.

The base portion 15 is shaped so that its width transverse to the direction of movement as shown in Figure 2a, and its depth in the direction of movement as shown in Figure 2, both increase inwardly towards the rotor core 12 and away from the outwardly extending arms 13 and 14. Preferably the rotor core 12 is a hollow tube, conveniently of circular cross-section, or alternatively of polygonal cross-section, as will be described hereinafter with reference to Figure 3.

The element 11 is preferably formed of resilient synthetic or natural material, such as polyurethane or rubber. Conveniently the base portion 15 is provided with a central axial aperture 16, and in the abutment region adjacent to the rotor core 12 it is provided with splayed feet forming a recess 17 in the unsecured position.

Figure 2b is a section of the element 11 of Figure 2a, seen in the direction of arrows BB. It shows in plan view the base portion 15 of element 11, in particular the diagonally splayed feet or corner lugs. When the element is secured to the rotor core tube 12 by tightening an axial fastener passing through the aperture 16, the corner lugs become splayed out further, as indicated by the chain-dotted lines. When the fastener is tightened down sufficiently, the lugs then hug a section of the tubular core cylinder both transversely and circumferentially. In consequence the element 11 is prevented in use from rotating about the fastener passing through aperture 16 by the splayed feet of the base portion 15 engaging against the rotor core 12. However, upon the element meeting an abnormal load, yielding can take place by limited deflection of two or more of the splayed feet of the base portion and/or by deflection of the resilient arms 13 and 14 in directions relative to the base region 15, including sideways deflection. Figures 2c, 2d, 2e and 2f show cross-sectional shapes of the arms 13 and 14 of element 11 in Figure 2a, as viewed in the direction of arrows BB. Each arm of Figures 2c and 2d has a groove 23 in the face of the arm which faces away from the other arm, and has rounded or inclined leading faces, as indicated at 22. This shape increases the rigidity of the arms and helps to counteract the tendency of the tip regions of the diverging arms 13 and 14 to move towards each other in use under the effect of centrifugal force. The leading edges impart a conditioning effect to the crop, the severity of the effect increasing with rotational speed.

The cross-sectional shape of arms 13 and 14 shown in Figures 2e and 2f give similar operational characteristics by virtue of their general shape and the inclination of the leading faces.

Figure 2g is a perspective view of one arm, 13, having a cross-section which varies from a rectangular or square section near the base of the arm to a triangular section at the outer tip. The triangular cross- sectional shape of the arm in the tip region and the incined face 22 provides an aerodynamic effect to counteract the tendency of laterally diverging arms to deflect towards each other under the influence of centrifugal force, especially when the effective length of arms 13 and 14 approaches or exceeds the dimension of the rotor core radius.

Figure 3 shows diagrammatically, partly in section, a crop engaging element 11 attached at the edge region of an hexagonal conditioning rotor core 12. It demonstrates the advantages of thread length in engagement with the axial fastening bolt passing through aperture 16 and of the stability which the element derives from being located to straddle the edge. Other cross-sectional shapes suitable for a rotor core include square, pentagonal, octagonal, etc.

To save on material from which the elements are made, the base region 15 may be provided with suitably shaped and dimensioned corner lugs, as shown in principle in Figures 2, 2a, and 2b, instead of full-width lugs. Preferably the arms of element 11 in Figure 3 are reclined in the direction of rotation to reduce in operation the load on the mounting device and to facilitate crop detachment from the arms. Figure 4 is a diagrammatic rear elevation of a crop engaging element 11 having outwardly diverging arms of diamond-shaped cross-section, as shown in Figure 2e. Near the base of arms 13 and 14 there may be provided apertures 24 extending the ^" full depth of the arms in the general direction of rotation. The apertures may be connected with the space between the arms by lateral slits. This causes the arms to be weakened in such a way that in operation the arms are able to yield more readily away from each other than towards each other.

The base portion 15 of element 11 in Figure 4 has a dowel 28 circumferentially spaced from the axial fastening hole 16, to prevent in operation any rotational movement, as is needed in heavy-duty applications. A cross-sectional side elevation of the dowel 28 is given in Figure 4a, showing that the dowel may be provided optionally with a curved heel and a protruding lip, to facilitate insertion into a correspondingly located hole in the cooperating surface on the rotor core member and firm retention therein.

The general arrangement of the base region is shown in plan view in Figure 5. Conveniently the circumferential spacing of fastening aperture 16 and dowel 28 may be varied in accordance with the operating requirements. To achieve substantial spacing, the dowel 28 may be located on a rearwardly extending pad 29 of rectangular or broadly triangular shape. The laterally diverging arms 13 and 14 in Figure 5 correspond with the shape of the arm shown in Figure 2g.

Figure 6 is a diagrammatic plan view of an alternative form of crop engaging element which has triangular-section arms 13 and 14 extending outwardly parallel to each other and normal to the transverse rotor axis. Inclined face regions 22 form an open funnel into which crop is forced during rotation, and depending on the bulk and density of the crop, arms 13 and 14 may be forced apart varying distances. Thus, a treatment effect is imparted to the crop by the leading edges of arms 13 and 14 over a transverse region of differing width, including twice the width corresponding to the normal spacing of the crop facing edges. To encour¬ age easy and mainly laterally directed deflection, the cross-sections of the arms near their base region may be reduced by chamfering to the areas shown to be shaded.

At 30 in Figure 6 there is indicated a shaped fin for locating and securing the element directly to the rotor core member in an appropriately shaped slot provided in the member. In Figure 7, which is a diagrammatic side elevation, partly in section, of a crop engaging rotor 1, the three lower elements 11 disclose details of the mounting fin arrangement. The slots provided in rotor core tube 12 are equal in width to the width of fins 30 but are less long circumferentially. Protruding lugs at the leading and trailing regions of fins 30 serve to lock the elements in position against the direction of rotation, and the width of flanges formed around base regions 15 provides lateral stability.

When fitting the elements, it is important to insert first the leading region of the fin into the slot, next to push the element forward so that the edge defining the slot at the front registers firmly in the front recess of the fin, and finally to lever the element rearwards so that deformation of the trailing lug, aided by the provision of an aperture 31, allows the fin to enter the slot fully. The element is locked in position by the trailing lug springing back to its normal disposition.

The other three elements In Figure 6 are shown to have trailing pads 29 with dowels 28 registering in holes 27 in the rotor core tube 12. The axial fastener 25 extending through the base portion 15 of element 11 may pass through a threaded hole in rotor core tube 12 or through a nut welded on the inside or outside of a plain hole in the rotor core tube, or it may be a self-tightening insert-type fastener.

Depending on the application, horizontally disposed crop treatment rotors may have between two and twelve transversely or helically extending rows of crop engaging elements. In some applications the transverse distribution of elements may be non-uniform, for example to compensate for concentrations of crop in regions along the working width.

Figure 8 is a front elevation, partly in section, of two different direct-mounted crop engaging elements having a common base portion 15. By way of example, the left-hand element is divided in its crop engaging region into two curved fingers 26 which diverge from each other. Near the inner base region a full-depth aperture 24 joined by a slit to the space between adjacent elements provides a region of reduced resistance of the arm to yielding transversely away from the fastening region.

The right-hand element, also by way of example, is divided into three fingers 26 and is waisted near, the base region by recesses 24 to facilitate lateral yielding in either direction. A shaped plate 33 may be provided under the head of mounting screw 25 to ensure that the whole of the base region is firmly clamped in position. Two dowels 28 prevent rotation of the element in operation. A batten 32 of timber or other material softer than steel may be provided to permit the use of fasteners with self-tapping threads.

Figure 9 is a front elevation, partly in section, of two crop engaging elements 11 linked by a common base portion 15 and having multiple fin¬ gers 26. A rigid saddle-shaped pressing or moulding 34 spans the base portion fore and aft, enclosing it except for the sides. As is shown in the side elevation of Figure 9a, which, is partly in section, the leading and trailing flanges of the relatively wide pressing 34 are firmly seated on the curved surface of rotor core 12, thus preventing rotation about the single fastener in operation.

The central arm of element 11 in Figure 9a may be provided in the trailing edge region along its outwardly extending length with one or more recesses 24 to facilitate rearward deflection. Fingers 26 may be of different length, and their leading edges may be reclined in the direction of rotation or lie in the same transverse plane.

Figure 10 is a front elevation of fingers 26 of alternative shape in the outer region of a crop engaging element 11. In the tip region the laterally inclined side fingers terminate in short radial lengths so that crop is able to slide off readily under centrifugal effect. The element of Figure 10 is particularly suitable for tedding crop lying on the ground, for picking up crop with rotors having horizontal axes, and for conditioning crop by rotors with vertical axes. Figure 11 is a front elevation of the outer part of a crop engaging element provided with lateral extensions 26 normal to the outwardly ex¬ tending arm 11. The lateral extensions may be of equal or different length, as indicated also in Figure 11a in full and broken outlines respectively.

Figure lib is a plan view of the element in Figure 11, showing the chevron or triangular shape of the lateral extensions 26. This form of element finds particular but not exclusive application in the treatment of uncut crop by rotors with horizontal axes driven in the overshot or undershot mode.

Figure 12 is a diagrammatic side elevation, on a reduced scale relative to the other figure, of a crop engaging rotor embodying the invention, the rotor operating in the horizontal or near-horizontal plane. As shown by way of example, the rotor core member 12 carries only one circumferen¬ tially disposed array of crop engaging elements 11, each having multiple fingers for sweeping over the ground or for engaging uncut crop when positioned, for example, over the cutting discs of a rotary mower.

Elements 11 may extend from the rotor core 12 radially or reclined in the direction of rotation, or they may form axial extensions of arms extending through apertures in the wall of the rotor core member, the arms being steered by an eccentric mechanism inside the rotor core member to change between the radial and a substantially reclined disposition during each rotation of the rotor. The latter feature is particularly effective for spreading or windrowing cut crop when, optionally, two or more rotors may be provided to cooperate side by side.

Other features of the aforementioned embodiments which are of particular advantage are as follows:

Preferably the reclined arms of crop engaging elements make an angle of between 10° and 25° with a radius passing through the base of the element. Particularly for conditioning crop by rotors with horizontal axes it is advisable to arrange the outwardly extending length of the elements to be not substantially greater than the radius of the core tube. Preferably the effective length relative to the core radius ranges between 1:1 and 1:3, most preferably 1:2. These dimensions help to keep down the amount of material required and the cost of manufacturing the elements, also the load exerted in operation of the device on the securing means. Additionally the arrangement counteracts any tendency for crop to wrap, especially when handling long materials.

The cross-sections of the arms which have been shown are shaped to avoid detrimental deflection as a result of centrifugal effect and to provide adequate stiffness in the crop engaging tip regions, in order to promote the efficient transfer of energy to the crop for treatment. The use of tapering cross-sections of arms of elements increases the treatment effect because of the narrow, though preferably radiused, leading edges which are presented to the crop.

The use of arms of elements having crop engaging faces shaped to deflect the arms laterally away from each other so that they become transversely inclined relative to the crop flow, due to aerodynamic effect and/or crop contact, provides a particularly safe form of element, requires relatively little drive energy, and is self-adjusting in that lateral deflection, and hence treatment effectiveness, is greatest in bulky crops and least in light crops.

Examples of dimensions which may be used for rotors with horizontal axes are: rotor core diameter 200 to 500 mm, preferably 400 mm; overall rotor diameter 300 to 1000 mm, preferably 550 mm; effective length of elements measured radially 70 to 220 mm, preferably 100 to 120 mm.

Examples of dimensions which may be used for rotors with vertical axes depend on the wide range of possible applications and include overall rotor diameters varying between 300 and 2000 mm.

Tip speeds of crop engaging elements may range from < 10 m/s for tedding, windrowing or spreading crop to 40 m/s for severe conditioning.

Claims

1. According to the present invention there is provided apparatus for conveying and/or treating crop comprising: a mobile support structure for movement over the ground; a rotor mounted for rotation relative to the support structure with its axis of rotation substantially parallel or normal to the ground, the rotor comprising a core member and a plurality of outwardly extending elements for engaging the crop; drive means for driving the rotor in rotation to engage the crop; each crop engaging ele¬ ment being formed of resilient material and comprising at least one out¬ wardly extending arm and a base portion, the element being shaped and mounted to maintain or attain in operation the required operating position, wherein crop engaging edges lie transversely inclined to a radial plane normal to the axis of rotation, or to return to the operat¬ ing position after yielding at regions along the effective length of the element in directions including transverse to the direction of rotation.

2. Apparatus according to claim 1 in which the base portion of the element has abutment regions shaped to cooperate with an abutment surface on the rotor core member so as to prevent dislocation of the element away from the required operating position under normal load conditions.

3. Apparatus according to claims 1 and 2 in which the rotor core member is a hollow member of circular or polygonal cross-section.

4. Apparatus according to claims 1 to 3 in which the fastening device extends towards or into the rotor core member in the general direction of the outwardly extending axis of the element.

5. Apparatus according to claims 1 to 3 in which crop engaging elements comprise in one piece two or more outwardly extending arms and a linking base portion.

6. Apparatus according to claim 5 in which pairs of arms extending outwardly and generally normal to the rotor axis have laterally slanting crop facing surfaces forming an open funnel in the direction of rotation so that the aerodynamic effect generated in operation and the crop impinging upon and passing through the funnel urge at least the outer regions of the arms away from each other.

7. Apparatus according to claim 5 in which pairs of arms diverge from each other in the outward direction and in a plane generally transverse to the direction of rotational movement.

8. Apparatus according to claim 7 in which the arms are provided along their length with grooves to increase their stiffness and the resistance to deflection by centrifugal effect.

9. Apparatus according to claim 7 in which the arms have laterally slanting crop facing surfaces forming an open funnel in the direction of rotation to increase resistance to deflection by centrifugal force of the outer regions, by virtue of crop contact and aerodynamic effect.

10. Apparatus according to claim 5 in which the leading edge regions of outwardly extending arms are reclined in the direction of rotation relative to the base regions.

11. Apparatus according to claims 1 to 5 in which the elements are mounted so that their base portions straddle an edge of a rotor core member of polygonal cross-section.

12. Apparatus according to claim 5 in which at least some of the arms divide in their outer region into two or more fingers or extensions having crop engaging edges which are laterally inclined to a radial plane normal to the rotor axis.

13. Apparatus according to claim 5 in which the arms are waisted or otherwise weakened near the base region to promote preferential yielding to one or both sides, to protect the elements from damage in operation.

14. Apparatus according to claim 5 in which the arms are provided with recesses in the trailing edge regions, to facilitate yielding in the rearward direction.

15. Apparatus according to claim 5 in which there is provided, a washer or plate under the head of the fastening means to spread the load in tightening over the upper surface of the base portion and to force the shaped abutment regions of the element into firm and close contact with the curved or otherwise profiled cooperating surface on the rotor core member.

16. Apparatus according to claim 5 in which there is provided under the head of the fastening means a rigid saddle-shaped cover spanning the base portion of the element fore and aft, transverse flanges of the cover engaging the rotor core member spaced apart circumferentially.

17. Apparatus according to claim 5 in which a crop engaging element is secured to the rotor core member by a combination of axial fastening means and, spaced from the fastening means, one or more lugs or dowels extending into the cooperating surface on the rotor core member.

18. Apparatus according to claim 5 in which a crop engaging element is secured by a fin extending axially into a correspondingly shaped slot provided in the cooperating surface on the rotor core member, the fin being shaped to provide a press fit and the laterally extending base portion providing lateral stability.

19. Apparatus according to claims 1 to 18 in which the crop engaging elements are formed to have an effective length relative to the rotor core radius in a ratio between 1:1 and 1:3.

20. Apparatus according to claim 19 in which biassing and yielding means and effects are provided in the crop engaging elements by the combination of the material from which the elements are made and the conformation of the outwardly extending arms.

21. Apparatus according to claim 20 In which the rotor has a horizontal axis of rotation, operates in the overshot mode and has a front cover providing a crop facing surface shaped so that the crop being impelled past it is subjected to a severe washboard effect whereby the crop is retarded, repeatedly re-directed into the path of the crop engaging elements and scrambled.

22. Apparatus according to claim 21 in which the section providing the washboard effect is joined to a top cover by a double-hinged plate or a length of flexible material and is lockable in positions which include equidistant throughout the effective length of the section relative to the periphery of the rotor.

23. Apparatus according to claim 20 in which the rotor has a horizontal axis of rotation and operates in the undershot mode.

24. Apparatus according to claims 21 to 23 in which the rotor is combined with a mower and is so mounted relative to the mower that the crop Is treated before, during or after cutting.

25. Apparatus according to claim 20 in which the rotor has a vertical axis of rotation.

26. Apparatus according to claim 25 In which one rotor is mounted over each cutting unit of a rotary mower so that the crop is treated before or during cutting, the rotor being driven in counter-rotation to the cutting unit.

27. Apparatus according to claims 1 to 26 substantially as hereinbefore described with reference to any one or any combination of the accompany¬ ing drawings.