The present invention relates to a header for agricultural crop, wherein the header is provided for mounting on a harvesting machine. The header comprises a support frame, a cutter bar arranged on the front side and having blades fastened thereto, and conveying elements for conveying away the cut stalk material. The conveying elements comprise at least two belt-type conveyors which convey the crop transversely with respect to the direction of travel of the header during harvest, and further comprise a centrally arranged belt-type conveyor as a middle belt, which conveys counter to the direction of travel of the header. Drive means for driving the cutter bar and the conveying elements are provided.
A header of the aforementioned kind is known from U.S. Pat. No. 7,444,798. The middle belt has, on its outwardly pointing surface, strips which are applied so as to be spaced apart from one another and which are obliquely inclined in trailing fashion toward the middle. The strips are intended to guide crop that is discharged onto the middle belt by the transversely conveying belt-type conveyors away from the lateral edges of the revolving middle belt toward the middle. This applies in particular to grain kernels, which are essential to the harvest yield but which can very easily roll away over the edges of the middle belt, and thus be lost in terms of the crop, in the event of shocks, wind, oblique positions of the header during harvesting, material accumulations and other disruptions in the harvesting process or material flow.
It has been found that the strips applied to the revolving middle belt are not sufficient to prevent grain losses over the lateral edges of the middle belt under all harvesting conditions. In particular in the case of difficult crop such as seeds of oilseeds, e.g. rapeseed, the grains continue to roll over the lateral edge despite the strips on the outwardly pointing surface of the middle belt. Here, a situation may arise in which the grains fall onto the inner side of the revolving belt, pass from there into the region of a deflecting roller of the middle belt, and are crushed there between the surface of the deflecting roller and the inner side of the revolving belt. The oil that emerges from the grains as a result adheres to the inner surface of the revolving belt and causes slippage of the driven deflecting roller on the inner side of the revolving belt, such that the belt no longer revolves in a correctly driven manner. The oil that adheres to the inner side of the revolving belt may furthermore become resinous in the air, and thereby cause the revolving belt to stick to the deflecting roller and give rise to vibratory, rough running of the revolving middle belt.
U.S. Pat. No. 7,182,202 discloses support parts fastened to edge-side belts of a belt-type conveyor for tubers. Upwardly projecting fingers formed on the support parts have an intermediate space between them. The support parts cannot be fastened to a middle belt because the belt material is too thin in relation to the conveyor belts. The support parts are also not flexible enough to revolve around the narrow deflecting rollers that are used in the case of belt-type conveyors, and in particular in the case of middle belts, over a relatively long period of time without sustaining damage. Furthermore, the intermediate spaces at the support parts are too large to be able to effectively retain grains.
Accordingly, it is the object of the present invention to protect the middle belt more effectively against grain losses over the lateral edge of the revolving belt.
For a header of the aforementioned kind, the object is achieved in that the middle belt has, at its lateral edges on its outwardly pointing surface, in each case one grain-blocking elevation.
The grain-blocking elevation is effective in preventing grain kernels or the grains of oilseeds from rolling over the lateral edges of the middle belt. Owing to their relatively low weight, the grains exhibit only low kinetic energy when they move on the surface of the middle belt transversely or obliquely with respect to the conveying direction of the middle belt. Elevations on the lateral edges have the effect that, when grains strike the side surfaces of the elevations, the grains are stopped in terms of their movement and move no further toward the lateral edge of the revolving belt.
The grain-blocking elevations are formed along the full length of the edges of the middle belt in order to prevent grain losses during a full revolution of the middle belt.
The grain-blocking elevations do not need to be of a large height in order to prevent the major part of the grain losses caused by grains falling laterally from the middle belt. A height of 0.5 cm over the outwardly pointing surface of the revolving belt is sufficient to stop many of the grains moving toward the lateral edge. A greater height self-evidently increases the proportion of grains that are intercepted.
The elevations may be cast directly into the material of the revolving belt if the revolving belt is produced in a casting tool. It is however also possible for molded parts which form the grain-blocking elevations to be applied to the material of the middle belt and fastened there, for example, by adhesive bonding, vulcanization, riveting or other suitable fastening techniques.
The grain-blocking elevations may be of continuously closed form over their entire height and width toward the belt surface. In the case of an excessively large height of the elevations, however, a situation arises in the region of the deflecting rollers in which the flexing work in the material of the elevations is so intense that the elevations can detach from the material of the revolving belt. By way of a restriction of the height of the elevations to a suitable dimension and an adaptation of the material used for the elevations to the flexing work and the temperatures that arise in the material as a result, and the use of a suitable fastening means for the elevations if the elevations are applied retroactively to the material of the revolving belt, it is possible to realize a still satisfactory service life of the elevations.
In one embodiment of the invention, the grain-blocking elevation has, over its length, a lateral offset transversely with respect to the direction of rotation of the middle belt. The lateral offset may be formed by virtue of the elevation being laid for example in loops. Sections of the grain-blocking elevation laid in loops are partially or predominantly oriented in the transverse direction with respect to the direction of revolution. Thus, during revolution about a deflecting roller, the material of the loops of the grain-blocking elevation is itself subjected to less intense tensile load in these sections than other sections of the grain-blocking elevation, which extend substantially or entirely in the direction of revolution of the middle belt. The material of the grain-blocking elevation thus forms, in the region of the loops, a material reserve for sections of the material of the grain-blocking elevation that are subjected to relatively intense tensile load. The material reserve can thus accommodate a part of the tensile loads that act on those sections which are oriented more in the direction of revolution, and can thereby reduce the average tensile load. During revolution about a deflecting roller, the tensile loads acting on the outer regions of the material of the grain-blocking elevation are thus lower, whereby the service life of the grain-blocking elevation and of the middle band is altogether greatly increased. The lateral offset of the grain-blocking elevation transversely with respect to the direction of rotation of the middle band however need not be implemented in loop form; a jagged profile in zigzag form or a profile with undulating patterns or other configurations are possible, for example.
In one embodiment of the invention, the grain-blocking elevations are formed with incisions, notches or free spaces which are oriented obliquely or transversely with respect to the conveying direction of the revolving belt and which extend over a part of the height or over the full height of the elevations. The incisions, notches or free spaces reduce the flexing work in the material of the elevations. Without the incisions, notches or free spaces, the material of the elevations will, during revolution about a deflecting roller, be stretched and compressed with increasing intensity in an outward direction over the height of the material, over the radius which becomes greater with increasing height, over the revolving length of the elevation. To the depths to which the incisions, notches or free spaces extend, the material of the elevations can now pivot forward in blockwise fashion during revolution about the deflecting roller, without pulling the material of an adjacent block of the elevation along with it, such that, during revolution about the deflecting roller, the incisions, notches or free spaces open in V-shaped and scissor-like fashion, and close again back into the initial position.
This effect can also be utilized for carrying along crop that falls onto the edge region of the middle belt. Such crop can at least partially fall into the incisions, notches or free spaces and be clamped there by the material. Held clamped in the incisions, notches and free spaces, the crop is then carried along in the conveying direction of the middle belt to the deflecting roller, where the incisions, notches or free spaces open in scissor-like fashion, and the crop that is held clamped is thereby released. In this way, the crop can then be moved further in the desired conveying direction away from the middle belt.
The notches may be formed as simple incisions or cutouts into the material of the elevations. The notches may however also be in the form of a free space which is formed between adjacent material blocks of the elevations. The shape, depth and width of the notches or of the free space should in this case be adapted to the crop that is intended to be restrained by the elevations. Excessively large free spaces lead to grain losses.
In one embodiment of the invention, multiple rows of grain-blocking elevations are arranged adjacent to one another in the longitudinal direction of the middle belt, which rows are separated from one another by incisions, notches or free spaces which extend at least substantially in the longitudinal direction of the middle belt. By way of multiple rows of grain-blocking elevations, the blocking action of the elevations formed at the edge of the middle belt can be increased. This applies in particular if, in the elevations, there are provided notches or free spaces which are narrowed or covered entirely by elevations of an adjacent row in the transverse direction.
In one embodiment of the invention, the rows of grain-blocking elevations have incisions, notches or free spaces which are oriented obliquely or transversely with respect to the conveying direction of the revolving belt and which are formed offset with respect to one another in the transverse direction of the middle belt. The individual blocks of the rows of elevations are thus arranged in staggered fashion, such that a grain can no longer roll through the incision, the notch or the free space between two adjacent blocks of a row, but rather is stopped at the latest by the staggered block of an adjacent row.
In one embodiment of the invention, the elevations are produced from an elastomer material. Owing to the elastomer material, the elevations have the elasticity required to be able to deform during revolution about the deflecting rollers.
In one embodiment of the invention, the grain-blocking elevations are composed of multiple mutually adjacently arranged rows of molded bodies, the molded bodies having in each case a spacing to the next molded body in the direction of the row, and the rows being arranged in staggered fashion with respect to one another. Such an arrangement offers a good compromise between durability and longevity of the elevation and the blocking action for prevention of grain losses.
In one embodiment of the invention, the molded bodies have a cylindrical basic shape.
In one embodiment of the invention, strips are applied to the outwardly pointing surface of the middle belt, which strips extend substantially transversely with respect to the conveying direction of the middle belt and have an undulating shape over their extent transversely across the middle belt. The strip of undulating shape has the advantage, during the revolution of the middle belt about the deflecting rollers, that the material of the strip can, in the case of corresponding elasticity of the material, pull material out of regions of the strip that are not yet situated in the region of action of the deflecting roller.
In one embodiment of the invention, the amplitude of the undulating shape of the strips applied to the outwardly pointing surface of the middle belt is greater than half of the circumference of a deflecting roller of the middle belt. By way of this amplitude height, it is ensured that, during revolution about a deflecting roller, the strip is not situated entirely in the region of action of the deflecting roller.
It is expressly pointed out that the embodiments of the invention described above are combinable in each case individually, but also in any desired combinations with one another, with the subject matter of the main claim, as long as there are no technical constraints preventing this.
Further modifications and embodiments of the invention will emerge from the following description of the subject matter and from the drawings.
The invention will now be discussed in more detail on the basis of exemplary embodiments.
In the exemplary embodiment shown in
The gaps or free spaces shown in
To the outwardly pointing surface of the middle belt there are applied strips 14 which extend substantially transversely with respect to the conveying direction of the middle belt and which have an undulating shape over their extent transversely across the middle belt. The amplitude of the undulating shape of the strips applied to the outwardly pointing surface of the middle belt is greater than half of the circumference of a deflecting roller of the middle belt.
The invention is not restricted to the embodiments above. It poses no difficulties to a person skilled in the art to modify the embodiments in a manner that would appear suitable to him or her in order to adapt it to a specific usage situation.
The specification incorporates by reference the entire disclosure of the two German priority documents 10 2015 116 951.7 having a filing date of Oct. 6, 2015, and 2015 117 787.0 having a filing date of Oct. 19, 2015.
While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.
Number | Date | Country | Kind |
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10 2015 116 951.7 | Oct 2015 | DE | national |
10 2015 117 787.0 | Oct 2015 | DE | national |