Harvesting apparatus

Abstract: A crop stripper has a moving shaker pan (14) between the stripper drum (4) and an auger (6) receiving the gathered crop parts from the drum. The pan has a conveying platform (16) arranged in a series of descending steps (16a,16b) from the stripper drum to the auger. It is constrained to oscillate in a manner in which the front end has both horizontal and vertical components of movement whereas the rear end moves along a small downwards incline. It is found that these features help to promote the rearward movement of crop parts such as grain, so reducing spillage in the space between the stripper drum and the auger.

Description: This invention relates to harvesting apparatus for gathering crop parts from a standing crop. It is particularly concerned, although not necessarily exclusively so, with crop strippers which comprise a stripping rotor for removing the crop parts to be harvested from a standing crop in order to discharge the gathered parts rearwards to an auger rotating in the opposite direction which conveys the stripped crop onwards, eg. to transfer it to a hopper. Crop strippers are conventionally used to harvest plant parts such as seed from the stems of the crop. Because there is always a risk of some of the stems being broken or torn from the ground and drawn into the machine, it is necessary to space the stripping drum and the auger sufficiently far apart to prevent these stems tangling themselves between the two rotary devices and so hindering their operation. Conventionally, a conveyor belt runs between the drum and the auger to prevent stripped crop parts falling to the ground in the space between them and to keep any material collected on it moving towards the auger. The conveyor belt and its drive add considerably to the cost of the apparatus. In addition the belt can be prone to wear, increasing the down time for maintenance. It would be desirable to omit the conveyor belt but, as indicated, greater problems can arise if the stripper drum and auger are simply moved closer together. It has been proposed (EP 241276) to place a pan providing a horizontal platform in the gap between the drum and auger, the platform being given a saw-tooth profile with alternating rearwardly and forwardly inclined surfaces. The pan is oscillated on a parallel motion linkage with the intention that the surfaces of the saw tooth profile give material on the pan a rearward movement towards the auger. The arrangement disclosed in this earlier publication is, however, unable to convey the crop parts in the required manner. According to the present invention, a harvesting apparatus is provided comprising means for gathering crop parts from a standing crop and an auger rearwards of the gathering means for conveying the gathered crop parts onwards, said gathering means and auger being spaced apart in the direction of movement of the gathered parts between them, transfer means being provided between the gathering means and the auger for urging gathered crop parts towards the auger, said transfer means comprising a pan or platform having a conveying surface, and means for oscillating said pan to drive the crop parts on it rearwardly towards a lower region of the auger, said oscillating means being arranged to produce a horizontal component of movement towards and away from the auger and a vertical component of movement which is greater at a leading gathering-means end region of said surface than at its opposite trailing, auger end region, and said conveying surface being lower at the trailing, auger end than at the leading end. It may be arranged that there is only a minor downwards and rearwards movement at the trailing edge, or even that there is essentially no vertical component of movement at the trailing region. In either case, preferably there is substantially no movement transverse to the extent of the conveying surface in that region. It is also preferred to arrange the conveying surface of the pan in a stepped form composed of a series of substantially horizontal faces alternating with downwardly extending faces which are directed rearwards. In a further preferred feature, the trailing end of the transfer means pan overlaps an auger pan extending rearwardly thereof under the auger and is located above the floor of the auger pan. Sealing means are provided between the underside of overlapping trailing end of the transfer means pan and the front end of the auger pan. These sealing means may comprise a sliding seal or a flexible diaphragm secured to the transfer means pan and the auger pan. The invention will be described in more detail by way of example with reference to the accompanying drawings, in which: Fig. 1 is a schematic side view of a crop stripper provided with a transfer means in accordance with the invention, and Fig. 2 is a side view similar to Fig. 1 but to a larger scale and showing more detail. In the drawing, the stripper casing 2 encloses a stripping drum 4 towards a forward end of the casing and an auger 6 at its rearward end, mounted on respective fixed rotary axes 4a,6a and being at a spacing from each other. The casing is open below the drum 4 so that, in conventional manner, the teeth on the drum can enter the crop as the stripper advances into the crop with the drum rotating, to remove the parts intended to be harvested. These crop parts are swept over the drum towards the auger 6 to be transported onwards. The space below the auger is closed by a closely spaced, fixed pan 12. Between the drum and auger there extends an oscillating transfer pan or platform 14 to prevent stripped crop parts dropping behind the drum 2 from falling to the ground and to convey them rearwards to the auger. The transfer pan 14 comprises a progressively downwardly extending surface 16 that leads onto the fixed pan 12 below the auger. The surface extends across the width of the stripper casing and descends from front to rear in a series of steps comprising substantially horizontal flat faces 16a (Fig. 2) alternating with almost vertical downwardly extending faces 16b. Plates 18 at opposite sides of the pan form side walls projecting above the surface to prevent sideways spillage of the crop from the pan. At the rear region of the pan, springs 20 are connected between the stripper casing and dependent flanges 22 on opposite sides of the pan. The springs 20 draw the rear end of the platform against a sealing bar 24 fixed to cross-beam 26 of the casing. At its forward region, the pan flanges 22 have pivots 28 attached to first lever arms 30 which are mounted on an oscillatory shaft 32 held in fixed bearings in the casing side walls. Further lever arms 34 project from the shaft to be journalled to the lower end of connecting rods 36, each of which has its upper end fixed to an eccentric roller 38 that orbits around a circular track 40 fixed relative to the casing. The eccentric rollers rotate with a drive wheel 42 conveniently driven by chain 44 from the main drive (not shown) for the stripper drum and auger. Movement of the eccentric rollers 38 around the tracks 40 causes the connecting rod 36 to oscillate the shaft 32. The oscillation is transmitted to the transfer pan 16 through the pivot 28 but the pan is also constrained by the springs 20 and abutting sealing bar 22 so that, while the pan moves forwards and rearwards as a whole, the vertical component of the movement at the pivot 28 is not transmitted to the rear portion of the pan. The rear of the pan thus performs a generally horizontal oscillation, inclined at a small angle downwards and rearwards as indicated by the arrows A. The first lever arms 30 are inclined upwards and forwards, towards the stripping drum 4, so that the oscillation of the shaft 32 causes the front of the pan 16 to move approximately tangentially to the envelope of the path swept by the stripping teeth on the drum, passing close to the front of the pan. The motion of the front region of the pan is indicated by the arrows B in Fig. 2 which also shows the shaker pan in opposite end positions in full and broken lines respectively. As a fail-safe provision, a bottom stop 46 for the pan motion is mounted on forward cross-beam 48. The different motions of the front and rear regions of the pan mean that the pan can be located close to both the stripper drum and the auger while providing an upward and rearward motion to the material falling on the front region to move it quickly away from the stripper drum. There is less risk of spillage of separated crop parts at the front of the pan, therefore, and at the rear the material is removed more quickly by the auger so preventing a build up that might spill over the sides of the transfer pan. At the region between the transfer pan 16 and the auger pan 12, the sealing bar 24 prevents spillage of the crop parts between the transfer pan 16 and the auger pan 12. The bar is a renewal plastics strip that provides a sliding seal between the two pans 16,12. It is found that the inclination of the transfer pan assists the movement of the crop parts towards the auger. This movement is also promoted by the fact that it is possible to impart a relatively vigorous shaking motion, including a substantial vertical component, in the forward region of the transfer pan without producing widely varying gaps between the pan and the stripping drum and/or auger at different points of the oscillatory cycle.

Claims: A harvesting machine comprising means (4) for gathering crop parts from a standing crop and an auger (6) rearwards of the gathering means for conveying the gathered crop parts onwards, said gathering means and auger being spaced apart in the direction of movement of the gathered parts between them, and transfer means being provided between the gathering means and the auger for urging gathered crop parts towards the auger, said transfer means comprising a pan or platform (14) providing a conveying surface (16), and means for oscillating said pan to drive the crop parts on it rearwardly towards a lower region of the auger being arranged to oscillate the conveying surface (16) with a horizontal component of movement towards and away from the auger (6), characterised in that said oscillating means is further arranged to oscillate the conveying surface with a vertical component of movement which is greater at a leading gathering-means end region of said surface than at its opposite trailing, auger end region, and the conveying surface is lower at the trailing, auger end than at the leading end. Harvesting machine according to claim 1 wherein said trailing end of the pan or platform (14) is arranged to oscillate substantially in the direction of the adjacent region of the conveying surface. Harvesting machine according to any one of claim 1 or claim 2 wherein said oscillating means are arranged to raise the leading region of the conveying surface (16) during a rearward movement of the oscillation. Harvesting machine according to any one of claims 1 to 3 wherein said oscillating means comprises a rocking lever mechanism (30-34). Harvesting machine according to any one of the preceding claims wherein the conveying surface of the pan or platform has a stepped form comprising a spaced series of downwardly extending faces (16b) which are directed rearwards. Harvesting machine according to claim 5 wherein said downwardly extending faces (16b) alternate with substantially horizontal faces (16a) of the conveying surface of the pan or platform. A harvesting machine according to claim 6 wherein the rearmost of said substantially horizontal faces (16a) is downwardly inclined in the direction towards the auger (6). Harvesting machine according to any one of the preceding claims wherein the trailing end of the pan or platform (14) overlaps an auger pan (12) extending under the auger (6) and is located above the surface of the auger pan in the region of said overlap. Harvesting machine according to claim 8 wherein sealing means (24) are provided between the underside of said overlapping trailing end of the pan or platform (14) and the front end of the auger pan (12). Harvesting machine according to any one of the preceding claims wherein the pan or platform (14) has upwardly extending side walls (18).

Inventors: MCCREDIE PAUL JOHN, SHELBOURNE KEITH H, MCCREDIE, PAUL JOHN, SHELBOURNE, KEITH H.
Applicants: SHELBOURNE REYNOLDS ENG, SHELBOURNE REYNOLDS ENGINEERING LTD.
Application year: 1995
Main classification: A01D41
IPC codes: A01D41