The present invention refers to a plants processor and crop head separator device for combine harvesters, preferably applicable in corn and sunflower crops, and adaptable to corn headers currently under use, this device is composed by at least one roll with its rotational axis positioned in angle as regards the forward movement of the header.
It is widely known that crop heads harvesting involves the following stages as basic principles: stage a) processing the plants, that is exploring the whole plant in search for crop heads, leaving the plant on the ground in optimal conditions for their integration with the soil, avoiding the entry of material that is not part of the crop heads to its processing systems (stalks, leaves, weeds, etc.); stage b) separating the crop head from the other parts of the plant; and finally stage c) gathering the crop head.
In the present specifications, there will be repeated references to stalk rolls or simply to the rolls, that are one of the main elements constituting the current systems and the reason for the present invention. In most cases, three surfaces can be clearly identified on the rolls, see
On a study carried out by the National Institute of Agricultural Technology in Argentine (INTA for its initials in Spanish) about grain loss in the corn harvest, two factors related to the combine harvester are highlighted: ground speed and adjustment of the stripper plates. These are of great importance when it comes to lowering the grain loss caused by the corn header.
This study informs that if there is an excessive ground speed, the corn header will pull the ears off the stalk in the rear part of the stripper plates, piling up several ears at the same time and causing some to fall in front of the header and others to suffer loss of seeds. Ideally, the ear should be pulling off the stalk at half way in the gathering chains. Once the speed issue has been solved, the space between the stripper plates edges will have to be correctly adjusted, which will be determined in relation to the stalks diameter and the size of the ears. If these two factors are uniform in the crop, the header adjustment is simple, but if any of these two factors are not uniform in the row, the stripper plates adjustment will not be a simple matter to solve. A practical rule for the adjustment of stripper plates is beginning to operate with the stripper plates as close as possible and then opening them until the combine harvester does not get stuck often.
The prior art ears separating systems feature rolls whose rotational axes are placed or positioned parallel to the header forward movement. We will designate those rolls as lateral rolls.
The lateral rolls with gear-like teeth, flutes or drivers, overlap those teeth, flutes or drivers edges in a synchronized fashion, they are cylindrical or rectangular in the rear end, mainly tapered with helical flightings all along or in the front end. These helical flightings are capable of taking in the plant between the rolls and thus facilitating the flow among them. Some lateral rolls systems feature stripper plates to protect the ears from the aggressiveness of the rolls.
The plant processor and crop heads separator device in the present invention featuring specially positioned rolls, hereinafter designated transverse rolls, fully meets the three principles previously stated and it will be explained in the following paragraphs.
In
The header configurations with transverse rolls mentioned before are some of the preferred realization modes but not all the possible ones. It should be noted that the 90° gearboxes, used by lateral rolls known until today, have been eliminated in all of them.
One of the advantages of this configuration of transverse rolls usage over the known lateral rolls is the possibility of increasing the roll diameter and/or rolls rotational speed without increasing the shearing action of the gathering chains and without the rolls pushing the stalks or cutting the plants.
The increase in the roll diameter and/or speed of rotation causes an increase in the tangential speed of the pulling surfaces of the rolls which increases the number of lineal meters of stalks and the number of ears processed by the different systems.
In a theoretical comparison between the transverse roll system 24 of the present invention and the prior art lateral roll system 25, where the operational variables are the same for both systems and where the only difference lies in the transverse rolls diameter, which is 50% larger than the lateral rolls, the increase in the tangential speed could be achieved by increasing the rotation speed or a combination of both, but for this comparison, the diameter is enough. The 5 km/h speed is drawn from the INTA report about the corn harvest where it is taken as the maximum optimal speed for lateral systems (3.5 km/h to 5 km/h), the 10 km/h speed is considered as the maximum speed above which the process capacity of the combine harvester could be affected, where the double amount of ears and crop residue would be processed by unit of time.
The ideal performance of transverse rolls 24 featuring 150 mm diameter rolls rotating at 1500 RPM, plant 26 distance of 200 mm, an estimated of 2000 mm of stalk to be processed per plant and one ear 27 per plant located at 1000 mm of the ground; Transverse roll perimeter: P=471 mm; Revolutions per second: 25; I=200 mm and 5 km/h ground speed as shown in
In the “I” interval, the transverse roll rotated 4.1 times, which equals 1932 mm of processed stalk, the first plant was processed along with its ear before the second plant entered the system.
At 10 km/h ground speed,
Now, the ideal performance for a lateral rolls system 25 (
In the “I” interval, the lateral roll rotated 4.1 times which equals 1290 mm of processed stalk, still remaining 700-mm to be processed from the first plant by the time the second enters the roll system. The ear of the first plant was processed before the ear of the second plant entered the system.
At 10 km/h ground speed,
From the performance of the two systems 24 & 25 it is concluded that at a ground speed of 5 km/h, the two systems practically process the same amount of stalks and ears (one stalk and one ear) but at 10 km/h, the lateral rolls 25 system must process an extra 50% of stalks and an extra 100% of ears than those processed by the transverse rolls 24 (3 stalks and 2 ears against 2 stalks and 1 ear of the transverse rolls 24). It is worth remembering that the lateral rolls system 25 can neither freely increase the roll diameter nor its rotation speed due to the pushing and dragging effect over the stalks and the limited space between rows.
With these initial parameters, a system of transverse rolls 24 at a ground speed of 7.5 km/h, processes the stalks and the ears in the same way (but at higher speed) than a lateral roll system 25 at 5 km/h, that is, a ear and 1290 mm of stalk are processed before the second stalk enters the system, an extra 50% in direct relation with the increase of diameter.
The performance of a stalk roll system, of any type, can be divided into three stages: stage a) In taking the stalk between the rolls so that it can be pulled, stage b) pulling down the stalk with a good enough grip to remove the crop head without cutting it up, and stage c) removing the crop head from the plant. At this stage, the systems are divided between those that separate the crop head directly over the roll surface and those that separate the crop head using stripper plates. These stripper plates are positioned above the rolls avoiding the passing of the crop heads between the stripper plates edges and separating them from the stalk by the pulling of the rolls.
The prior art lateral rolls with their conic elongated bodies, working in pairs, rotate in opposite directions in a synchronized and engaged manner (see
The lateral rolls require a synchronized and engaged rotation, this is a very important factor and everything is designed and built in order to ensure this, that is to say: The 90° gearboxes, the splined shafts, the flutes or drivers and helical flightings in their building and their assembly position, the rolls with joints threaded to the 90° gearboxes are assembled with high tightening torques to avoid movement during their operation. Synchrony failures can produce contact between rolls, breakage, premature wear, stalk cuts and jamming, among others.
On the other hand, the transverse rolls, such as those shown in the present invention (see configuration
In order to accomplish stage “a”, the lateral roll systems 28 (
The issues related to the conic ends are associated with the operational area and the building area, the latter has to do, first with the fact that when the roll is not a single-piece cast, the conic ends with the helical flightings are pieces separated from the roll body, that must be cast or forged and then assembled to the roll body by welding or threading. In their building, helical flightings should not have sharp edges; they must be left-hand helical flightings and right-hand helical flightings and operate, with the other adjacent roll, in a properly out-of-phase and synchronized manner.
When cast, the conic ends and helical flightings add weight to the rolls, they must be smoothed and sometimes mechanized to avoid contact between rolls, those that are welded add qualified manpower and the materials utilized are softer than the casting by which they must be treated to increase its harshness and avoid premature wear.
The operational area presents many issues. If the helical flighting is too high, it does not allow an adequate incoming of the stalk by “pushing it”, this also takes places if the passage is narrow or if the helical flightings of one roll are not properly out-of-phase from the helical flightings of its adjacent roll, which may cause them to come into contact or close enough to cause stalk cut or incoming difficulty. If the helical flighting pitch is wide, the helical flightings function as drivers, capable of cutting the stalk, and if the revolutions are high, being overlapped, they form a “solid” panel, similar to that of fan blades, avoiding the incoming of stalks; this pushing produces a shearing effect causing the gathering chains to cut off the stalks or to break them up so that they fall on the header producing jamming or entering the combine harvester without being processed. If the helical flighting are too low or the cone is too acute, they lose traction, remaining the stalk entrance between the rolls in charge of the gathering chains and the forward movement of the header.
In order to accomplish stage “b”, the lateral rolls 28 use flutes, drivers or gears-like teeth 33 in the roll body 32, that when overlapping, they grasp and pull the stalk downwardly, at this point, in order to accomplish stage “c”, those that remove the crop head over the rolls differentiate over those that utilize stripper plates . The former must have little aggressive traction surfaces with rounded edges or teeth so that they do not “bite” or hurt the ear causing seed loss making them prone to wearing, which, when it takes place, considerably decreases the traction effect, and thus the ears do not separate appropriately from the stalk being then beaten by the gathering chains and thus producing seed loss and stalk breakage that is sent to the inside of the combine harvester. For this reason, in order to assure traction, the aggressiveness of the rolls is increased using mainly high-wing intercrossed drivers, which makes them less prone to wearing but does not allow contact between the ear and the rolls surface since it would probably mutilate it instead of separating them, pulling it downwards. In order to avoid this, the systems use a set of stripper plates that protect the ear from the rolls when removing the crop head. This may be problematic due to different stalks and ear sizes, which forces to constant adjustment of the stripper plate edges distance since when they are too far apart, they would not have a good grip of the ears and can this to pass through, and when too tight, the stalks would get stuck with consequences over the pushing of the plants (stalk cuts and breakage). Also, either way, an increase in the rolls rotation speed would make the overlapped drivers or flutes edges forms a solid panel thus hindering movement or producing stalk cut.
In a configuration as the one shown in
The front faces 36 of the opposite rolls 35 make the chamber “B” 39. The plants enter into the chamber “B” 39 due to the header forward movement and the gathering chains operation. Once inside chamber “B” 39, the plant reaches its rear part, which is with the front faces 36 of the opposite transverse rolls 35. At this point, the rotation of the upper part of the opposite rolls 35 moves in the same forward movement as the plants 37, which causes it to be stuck and forced to move to chamber “A” 40, when the side walls of chamber “B” 39 tighten the stalk and pull it downwards. Once the stalk is located in chamber “A” 40, it begins to be pulled by the opposite rolls side faces 38, pushing the stalk against the rear wall 41 of chamber “A” 40, the main requirement of the rear wall 41 of chamber “A” 40 is low-friction coefficient and high wear-proof and its shape will be the most adequate to the rolls variable geometry. Stuck between the side faces 38 and the rear wall 41, the stalk begins to go downwards with no possibility to return due to the little passage between the rolls 35, the rotation of the opposite rolls 35 and the new incoming stalks 42. While going downwards, the ear touches the top of the rear wall 41 and gets stuck against the side faces 38 that continue to pull the stalk downwards while rotating, until it removes the ear.
These stages show the functioning principle of transverse rolls in one of their possible configurations, its building is simple, and they function neither engaged nor synchronized. Because the transverse rolls are rotating piece allows for an easy mechanization, its functioning does not require 90° gearboxes or fine adjustments, and can be done through transmission belts, thus lowering building costs and equipment weight. An increase in rotation speed instead of hindering the movement of incoming plants increases its speed towards the inside of chamber “A” 40. The rear wall 41 of chamber “A” 40 may be built with wear-proof material, which can be easily replaced once reaching its end-of-life. The side face 38 can be also made of wear-proof material, which can be replaced once reaching its end-of-life without having to replace the entire roll 35.
Also, an increase in traction is described in
We notice in
In the opposite rolls with flexible bands of
Also, both flexible bands 49 in their descent remain close to each other producing a curtain 52, as indicated in
In the lateral rolls of the prior art, see
Some conic ends 54 have helical flightings 30 & 31 to favor the entrance of plant between the side faces 55, but this job is mainly done by the gathering chains which effectively force the entrance of plant to the lateral rolls system.
The front faces 56 in opposite transverse rolls 57,
In other word, among the advantages of the transverse rolls over the lateral rolls of the prior art, we can mention the following:
Since they are rotation pieces, their building is simple (see example of four rolls
The transverse rolls diameter are not limited by the distance between rows as it is the case with lateral rolls, a larger diameter implies less rotations to pull the entire plant downwardly.
In the lateral rolls, by increasing its rotation speed, the overlapping flutes or drivers edges begin to form a “solid” impenetrable panel hindering the plants forward movement. This hinders the performance of gathering chains and row divider points to enter the plants into the system, producing a shearing effect between the gathering chains and the plants thus causing ear loss due to their downfall or to greater amount of material to be processed by the combine harvester. In the transverse rolls system, the transverse rolls rotation accompanies the plants progress inside the system by which the increase of rotation speed does not hinder their progress.
An increase in the harvest speed implies a greater amount of plants to be processed by the system. The process increase can be achieved in two ways: by increasing the speed of rotation and/or the rolls diameter; this is not limited in the transverse rolls system as it is in the lateral rolls system according to the previous two items.
The separation of the ear from the plant is produced at a certain point near the consolidating auger. This reduces the loss of ear on the ground and the gathering chains shearing effect.
Being the normal transverse rolls or fixed anti-friction surface are faced to the relative progress of the plants and weeds, they cannot pile up over the equipment at the end of the trajectory since they are pulled downwards when they come into contact with the side faces of the transverse rolls, this is because the opposite rolls and the new plants and weeds that enter the system push the previous ones ensuring the traction. In the lateral rolls system there is a blind spot at the rear end where the material that has not been pulled by these may pile up, causing jamming, which must be withdrawn manually resulting in a loss of time.
The lateral rolls system operate in a synchronized manner, a loss of synchrony would cause contact of the flutes or drivers edges or helical flightings, causing serious damage to the system thereby requiring adjustments in precision and 90° gearboxes for its correct operation. The transverse rolls system does not necessarily require synchrony in its functioning, thus the working of the opposite rolls 101 can be achieved by means of the normal roll 102 (by friction or engaged as shown in the 2-roll configuration in
By using smoother or less aggressive rolls, the separation of the crop head from the plant can be made directly on them, thereby making unnecessary the use of stripper plates.
The lateral rolls have helical flightings all along their surfaces or in their front ends to make possible the plants entrance and their trajectory between the rolls. In a pair of lateral rolls, the rotation between rolls is opposite, this implies that the helical flightings must be left-hand helical flightings and right-hand helical flightings and also the rolls must be left-hand rolls and right-hand rolls, thereby increasing the cost of manufacturing and spare parts. The transverse rolls do not require helical flightings to make possible the plants entrance and its trajectory between the rolls thus a single roll type may function as normal or opposite roll (see the four-rolls configuration). This produces lower manufacturing costs and lower amount of spare parts.
All these advantages allow corn headers to be built with few moving parts, lighter weight, low maintenance cost, greater harvest speed and reduced grain loss.
So as to make the object of the present invention more intelligible, it has been illustrated with design figures of its desired mode of realization, which act as demonstrative examples, as follows:
a to 5d are part of a comparison between the system of lateral rolls of the prior art and the transverse rolls of the present invention.
a to 16d show the detailed functioning for the configuration of three-rolls according to the present invention;
a and 25a show a system of transverse rolls without normal transverse roll;
b and 25b show a system of opposite rolls with flexible bands;
c and 25c show a system of opposite rolls with flexible bands;
It is worth noticing that equal references of the figures correspond to equal elements of the invention.
In order to explain the transverse roll operational principle,
In the detailed operational description, of the one-roll configuration the sequence shows how the plant with the crop heads 60, it bends and moves underneath the roll 61 with no difficulties and without causing the roll 61 to drag over the plant 60. In the sequence of
The operational sequence of
The plant 65 enters the system by passing through the stripper plates 63 without any hindrances until it comes in contact with the transverse roll 62.
In this moment begins the traction of the plant 65 towards the ground between the stripper plates 63 due to the rotation and the pressing of the roll 62 over the plant 65 and against the ground. In its downward movement, the plant 65 may bend in the forward-like direction 67 of the system but it is always contained by the stripper plates 63 that are long enough to avoid the plant 65 escape, and do not let the ears 66 to pass between them. There is no such dragging of the plant 65 against the ground because it is stuck between the ground and the roll 62. At this point the roll 62 may rotate by the dragging of the system over the ground or the roll 62 may be self-propelled to ensure it rotates over the plant 65 avoiding it to skid over it.
The ears 66 make contact with the stripper plates 63 and this produces their separation from the plant 65.
The plant 65 is pulled downwards following its descent between the stripper plates 63, passing underneath the roll 62 until they are left over the ground practically uncut, the ears 66 are dropped on the stripper plates 63 ready to be gathered.
The system of stripper plates for the separation of ears from the plant has been duly tested since it is already being used in current harvesting systems.
This description shows in a simple way the transverse rolls system operation principle for the pulling and separation of the ears from the corn plant in which the three principles previously stated are met. In actual practice, a wide range of situations arise such as fallen or cut plants unable to conveniently enter the system or the piling of ears and plant residue over the stripper plates that must be entered into the combine harvester for its processing.
Thus, conventional headers feature a system of gathering chains 68 (
The transverse rolls with rotation movement which allows them to move in the same forward-like fashion as that of the header, as shown in
The normal transverse roll rotation speed operating against the ground depends on the combine harvester ground speed, at a low ground speed, the plant is lowered more slowly and in softer soils, the rolls tends to sink or bog down. To free the normal roll rotation speed from the header forward movement, it must be detached from the ground thereby causing loss of traction over the plant. In order to keep the traction over the plant, it is necessary to use at least an extra transverse roll but rotating counter-rotating as regards the normal roll. These rolls with inverse rotation as regards the normal rolls are called rolls rotating in opposite direction or opposite rolls.
The function of the opposite rolls is pulling the plant inwardly between its side faces and the side face of the normal roll to pull it downwards towards the ground and separate ear from the plant if used as replacement of stripper plates.
The 16a, 16b, 16c and 16d sequence show in detail the way this takes place in a three-roll configuration:
Even though the plants are attached to the ground and what actually moves is the header, in order to clearly explain how the system works, it is relatively considered that the plants “enter” or “move towards” the rolls system, this relative movement is caused by the forward movement of the header, the pulling effect of the gathering chains on the plants towards the inside of the system and the rotation direction of the opposite rolls. First, the pulling down effect of the transverse rolls is described:
The sequence above shows the opposite rolls 71 rotating in an opposite-direction to the normal roll 72, the opposite rotation of the opposite rolls 71 causes their upper section 73 to move in the same forward-like movement as the plants and the lower section 74 to move opposite to the upper section. Opposite rolls 71 conform between them, in the front section, an opening angle, which allows the plants to pass between them, while the opening in the rear section is minimum allowing a crushed plant to pass without cutting it.
As the plant moves forward between the front faces 75 of the opposite rolls 71, this space begins to close until the plan gets stuck (
Second, the crop head separating process is described:
In order for the plant to go through the rolls faces 76 & 77 (
In the configuration of four identical transverse rolls with counter rotation by transmission belts of
Since the rotation of the transverse rolls is not necessarily synchronized, this configuration uses a transmission belt 90 in order to reverse the rotation of the opposite rolls 87, which simplifies and lowers the costs of the manufacturing process due to the fact that it does not need gears thereby causing fuel and maintenance savings.
All normal transverse rolls are assembled over a common shaft connected directly to the header drive shaft (as in
The system of transverse rolls may be used to process the plants, to separate the crop heads or both simultaneously, if it is used to separate the crop heads, the aggressiveness of the rolls surface must be slight, preferably without flutes or drivers that hurt the ear causing grain loss; in order to guarantee traction, the rolls diameter may be enlarged increasing the contact surface between the plant and the rolls, this diameter increase is limited since with large diameters, the crop head may be crushed by the rolls without producing the crop head separation. Another way to increase the contact surface between the plant and the rolls system lies in using sets of transverse rolls and flexible bands, such as those previously explained which increases the contact surface which depends on the bands length and not necessarily on increasing the rolls diameter. The flexible bands may be single or multiple, metal chains, belts, rubber bands, etc. The rolls may feature V-shaped slots for V-belts, teeth for chains, slots for indented belts or they may be simply plain for plain belts for the flexible band dragging, all these elements have the advantage of being of easy construction or easy to obtain. Another system advantage is that plants and weeds tend to wrap around the rotation pieces such as the rolls, but since the flexible bands covers the rolls, these wrappings are no longer possible.
In
a & 25a shows a system of transverse rolls in which the normal transverse roll has been left out, the flexible bands 94 pressure against a sliding surface 91 with an adequate radius in its upper part to perform the separation of the crop head 92 from the plant 93.
b & 25b shows a system of opposite rolls 95 with flexible band performing against a normal transverse roll 96.
c & 25c shows a system of opposite rolls 97 with flexible bands 99 performing against a normal transverse roll 98 with flexible band 100.
Another variant of the transverse rolls system is the 2-roll configuration as follows:
The design in
Generally speaking, the present invention consists in both a plants processor device and crop heads separator device for combine harvesters equipped with a row crop harvesting header with gathering zones at the front in which there are one, two, three or more rotating rolls, not necessarily with the same diameter or shape, where the rotational axes are positioned in a cross-like fashion to the combine harvester forward movement, that is, forming an angle as regards that forward movement and where at least one of them counter-rotates as regards the combine harvester forward direction and others do it in the same direction, not necessarily in a synchronized manner nor at the same speed; the function of the former is to introduce with their front faces the plants and the weeds between their side faces and the rolls side faces rotating in a forward direction where they are compressed and pulled downwards along with the crop heads. When these crop heads touch the upper section of the rolls, due to their shape and toughness, they do not pass between the rolls thus causing their separation from the plant by pulling, the plants and the weeds continue their downward movement between the rolls until they lie on the ground without entering the threshing system.
In one preferred mode, at least one of those rolls rotates in an opposite direction to the combine harvester forward movement and others rotate in the same direction, not necessarily in a synchronized fashion nor at the same speed, the rolls rotating in an opposite direction have the purpose of introducing plants and weeds with its front faces between their side faces and the rolls side faces rotating in a forward-like fashion where they are crushed and pulled downwards along with the crop heads, these crop heads do not touch the rolls but a set of stripper plates similar to the equipment currently used, positioned over the rolls with a distance between edges that allows only the stalks but not the crop heads to pass by. This allows for an increase in the roll system traction by means of an increase in their diameter, the use of the gear-like teeth, flutes or drivers, which are all quite aggressive toward the crop heads.
The opposite rolls will replace the front helical flightings of the lateral rolls known until today, for the incoming of the stalks to the pull-in area, lateral rolls have conic ends with left-hand helical flightings and right-hand helical flightings rotating in an accompanied and overlapped fashion, forcing the stalks to come in contact with them at entering between the rolls. The front faces of the opposite transverse rolls perform this function without offering resistance to the header forward movement or cutting the stalks by shearing them with the gathering chains or by abrasion produced by rotation of the helical flightings against the base of the stalk.
In another preferred mode, there will be a choice of transverse rolls with flexible bands, consisting in the use of sets of transverse rolls and flexible bands where the contact surface plant-roll depends on the length of the flexible bands and not on the rolls diameter. The flexible bands may be single or multiple, metal chains, belts or rubber bands.
In a preferred mode, at least one of the rolls with its rotational axis positioned in angle as regards the forward movement of the combine harvester will rotate in the combine harvester forward direction and the others (if any) will rotate opposite to the combine harvester forward direction.
We certify that what has been described and illustrated is only a preferred mode of implementation of the present invention and that any other implementation covered by the claims developed hereinafter will be considered included within its scope.
Number | Date | Country | Kind |
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P080104160 | Sep 2008 | AR | national |